JP2017509771A - Condensed tannin foam - Google Patents

Abstract

Disclosed is a condensed tannin-based foam comprising a formaldehyde-free polymer phase defining a plurality of open cells and a plurality of closed cells, wherein the formaldehyde-free polymer phase is an acid-catalyzed tannin derived from a surface active condensed tannin Base resin, formaldehyde-free tannin-reactive monomer, saturated or unsaturated organic anhydride, polyamine, ethoxylated castor oil, and optional plasticizer. Mixed tannin-phenol foams and methods of making the same are also disclosed.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a US Provisional Patent Application No. 61/973074 filed on March 31, 2014, and is filed on September 24, 2014, which is incorporated herein by reference in its entirety. No. 62/054471 is claimed.

  The present disclosure relates generally to condensed tannin foams, particularly formaldehyde-free condensed tannin foams and mixed tannin-phenol foams.

  Proanthocyanidins, also known as condensed tannins, is a type of polyphenolic compound found in several plant species, oligomers and polymers of polyhydroxy-flavan-3-ol monomer units, carbohydrates and traces Of amino acids and imino acids. Condensed tannins are the second most common family of natural phenolic compounds after lignin found in virtually all families of plants. The main commercial sources of condensed tannin extracts are those derived from quebraco (Schinopsis balansae) heartwood and mimosa or Morishima acacia (Acacia mearnsi) bark. The phenolic nature of condensed tannins provides the ability to condense with formaldehyde and other aldehydes to form crosslinked networks (thermosetting resins and foams). Tannins have long been used because formaldehyde-based resins (either urea-, melamine- or phenol-resins) are by far the most common raw material for the preparation of adhesive formulations for wooden panels. It has been regarded as a potential substitute for phenol in making such resins.

  One of the main problems with raw materials from renewable sources such as condensed tannins for use in industrial applications is that the process affects the reproducibility of the process and the properties of the products obtained from such raw materials. Is inconsistent. As disclosed by Gujrathi and Babbu in Energy Education Science and Technology, 19 (1), 37-44, 2007, the tannin content of bark is the age, bark thickness, soil condition, Varies depending on rainfall and other environmental factors. Also, the components present in commercially available condensed tannins depend on the extraction method (time, temperature and solvent) and the small amount of undisclosed chemicals added after extraction to maintain the quality of the tannin extract. Change.

  Accordingly, there is a need for a condensed tannin extract composition that provides batch-to-batch reproducibility and thus provides a foam useful for industrial applications.

In one aspect of the teachings of the present invention, a condensed tannin foam comprising:
(A) a formaldehyde-free polymeric phase defining a plurality of open cells and a plurality of closed cells having an open cell content measured in accordance with ASTM D6226-5 of less than 15%,
-An acid-catalyzed tannin-based resin derived from surface-active condensed tannin, formaldehyde-free tannin-reactive monomer, saturated or unsaturated organic anhydride, ethoxylated castor oil, and any formaldehyde-free polymer phase A selective polyamine and / or plasticizer,
The surface active condensed tannin has a surface tension of less than 53.0 mN / m when dissolved in 50% by weight of water;
-Formaldehyde-free tannin-reactive monomer is furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF) ), Glycerol, sorbitol, or a mixture thereof,
The saturated and unsaturated organic anhydrides comprise at least one of maleic anhydride, acetic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride and trimellitic anhydride;
The polyamine is a formaldehyde-free polymer phase comprising at least one of urea and melamine;
(B) one or more blowing agents disposed in at least some of the plurality of closed cells, wherein at least one of the blowing agents is isopentane, isopropyl chloride, 1,1,1,4,4,4 One which is an azeotrope or azeotrope-like mixture with one other blowing agent selected from the group consisting of hexafluoro-2-butene and 1-chloro-3,3,3, -trifluoropropene Or a plurality of blowing agents;
There are condensed tannin-based foams having thermal conductivity with time of less than 25 mW / m · K measured at 25 ° C.

In another aspect of the teachings of the present invention, a method of making a condensed tannin foam comprising:
(A)
10-80 wt% surface active condensed tannin having a surface tension of less than 53.0 mN / m when dissolved in -50 wt% water;
-Furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF), glycerol, sorbitol, or those 5 to 80% by weight of formaldehyde-free tannin-reactive monomer, including the mixture;
Forming an aggregate-free solution comprising 5 to 20% by weight of water;
(B) adding 0.5-20% saturated or unsaturated organic anhydride to the aggregate-free solution;
(C) 0.5-20% by weight of polyamine may be added to the aggregate free solution such that the organic anhydride and polyamine are present in a weight ratio of 1: 0.1-1: 1. The polyamine comprises at least one of urea and melamine;
(D) adding 0.5-20% by weight of a blowing agent to the agglomerate-free solution to form a preform mixture;
(E) adding 1 to 20% by weight of an acid catalyst to the preform mixture to form a formaldehyde-free foamable composition,
0.5-10% by weight of a surfactant is added to at least one of steps (a), (b), (c), (d), or (e);
A step wherein the amount in weight percent is based on the total weight of the foamable composition;
(F) foaming a formaldehyde-free foamable composition at a temperature in the range of 50-100 ° C. and curing to form a foam comprising a formaldehyde-free polymer phase defining a plurality of bubbles, And one or more blowing agents are disposed on at least some of the plurality of bubbles.

In another aspect of the present teachings, a method of making a mixed tannin-phenol foam comprising the steps of:
a) Heating the surface active condensed tannin in air or nitrogen for a period of 2 to 48 hours at a temperature in the range of 110 to 200 ° C. to substantially add one or more volatile compounds having a boiling point above 277 ° C. And thereby forming a volatile substance-free condensed tannin, when the surface active condensed tannin is dissolved in 50% by weight of water, a surface tension of less than 53.0 mN / m A process comprising:
b)
-10 to 80% by weight of volatile substance-free condensed tannin,
-Furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF), glycerol, sorbitol, or those 5 to 80% by weight of formaldehyde-free tannin-reactive monomer, including the mixture;
Forming an aggregate-free tannin solution comprising 5 to 20% by weight of water;
c) adding 10-90% by weight of a phenol-resole prepolymer to the tannin solution of step (b) to form a tannin-phenol resole mixture,
The phenol-resole prepolymer is derived from phenol and a phenol reactive monomer and further comprises urea;
-Phenol-reactive monomer is formaldehyde, paraformaldehyde, furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, levulinate ester, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF) And at least one of sorbitol,
d) adding at least one blowing agent to the tannin-phenol resole mixture;
e) 0.5-20% of saturated or unsaturated organic anhydride may be added to the tannin-phenol resole mixture;
f) 0.5-20% by weight of polyamine may be added to the tannin-phenol resol mixture;
g) adding 0.5-20% by weight of blowing agent to the tannin-phenol resol mixture to form a preformed tannin-phenol resol mixture;
h) adding 1-20% by weight of acid catalyst to the preformed tannin-phenol resole mixture to form a tannin-phenol resole foamable composition;
i) adding 0.5-1.5% by weight of a surfactant to at least one of steps (b)-(h),
A step wherein the amount in weight percent is based on the total weight of the tannin-phenol resole foamable composition;
j) foaming and curing the tannin-phenol resol foamable composition at a temperature in the range of 50-100 ° C. to form a mixed tannin-phenol foam comprising a polymeric phase defining a plurality of cells; And wherein one or more foaming agents are disposed on at least some of the plurality of bubbles.

  The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure as defined in the appended claims.

The influence of maleic anhydride on the moisture absorption by the condensed tannin foam is shown. Commercial condensed tannin extracts from two different geographic regions: GC-MS headspace spectra of tannin-A and tannin-F, respectively. Indicates. Commercial condensed tannin extracts from two different geographic regions: GC-MS headspace spectra of tannin-A and tannin-F, respectively. Indicates. Commercial condensed tannin extract: as-obtained tannin-F; volatile substance-free condensed tannin obtained by heating as-obtained tannin-F in air; and as-obtained tannin-F Shows a GC-MS headspace spectrum of each of volatile substance-free condensed tannins obtained by heating in water. Commercial condensed tannin extract: as-obtained tannin-F; volatile substance-free condensed tannin obtained by heating as-obtained tannin-F in air; and as-obtained tannin-F Shows a GC-MS headspace spectrum of each of volatile substance-free condensed tannins obtained by heating in water.

  The disclosures of all patent documents and non-patent documents cited in this specification are incorporated herein in their entirety.

  As used herein, the term “surface active condensed tannin” refers to a biologically derived condensed tannin having a surface tension of less than 53.0 mN / m when dissolved in 50% by weight of water. The amounts in weight percent are based on the total weight of tannin and water.

As used herein, the term “volatile substance-free condensed tannin” refers to a surface active condensed tannin composition that is substantially free of one or more volatile compounds. The plurality of volatile compounds have boiling points above 277 ° C. when analyzed by the GC-MS headspace method disclosed below. As used herein, the phrase “condensed tannin composition substantially free of one or more volatile compounds” is measured by the GC-MS headspace spectrum disclosed below, and the peak The amount of individual volatile components, expressed as area, having a boiling point greater than 277 ° C. is less than 1.0 × 10 ⁻⁵ , or less than 0.7 × 10 ⁻⁵ , or less than 0.5 × 10 ⁻⁵ Refers to the tannin composition. As used herein, the phrase “removing one or more volatile compounds” refers to one having a boiling point above 277 ° C. as measured by GC-MS headspace spectrum by evaporation. Or refers to further reactions that result in a significant decrease in peak intensity of multiple volatile compounds and / or formation of non-volatile compounds. 3B and 3C show the respective GC-MS headspace spectra of volatile-free condensed tannins obtained by heating tannin-F as received in air and nitrogen. As shown in FIGS. 3B and 3C, the volatile material-free condensed tannin is substantially free of one or more volatile compounds having a boiling point above 277 ° C. For comparison, FIG. 3A shows the GC-MS headspace spectrum of commercially available condensed tannin extract as obtained, tannin-F containing one or more volatile compounds having a boiling point above 277 ° C. .

  As used herein, the term “surface active condensed tannin” is used interchangeably with “condensed tannin” and “tannin” and refers to biologically derived condensed tannin.

  As used herein, the term “biologically derived” is used synonymously with “biologically derived”, obtained from plants, large amounts of renewable carbon, and small amounts of fossil fuel systems. Or refers to compounds including monomers and polymers containing petroleum-based carbon, and small amounts of chemicals can be residues from the extraction process or additives added for stabilization or other purposes.

  As used herein, the term “bio-based composition” refers to a composition containing at least 25% renewable carbon and less than 75% fossil fuel system or petroleum-based carbon.

  As used herein, biologically derived tannins are plant-based and extracted from leaves and buds, seeds, roots, bark, trunks, nut shells, fruit peels, and stem tissue of plants and trees Is done. As used herein, the term “mimosa tannin” refers to tannin extracted from the leaves, buds, seeds, roots, bark, trunk, or stem tissue of mimosa trees. Condensed tannins include, but are not limited to, bark such as acacia, mangrove, oak, eucalyptus, tsuga, pine, larch, and willow; It can also be extracted from other plant resources including fruits such as Milobaran, Valonia, Divi-Divy, Terra, and Carob (Algarrobilla); Leaves such as Ursi and Acacia; and roots such as canaigre and palmetto palm. The main commercial sources of condensed tannins are quebraco (Sinopsis balansae) heartwood, mimosa (Acacia mearnsii), Morishima acacia tree (Acacia molisima), acacia acne gum And pine (Pinus radiate, Pinus pinaster) bark, spruce (Picea abies) bark, pecan (Carya illinoensis) bark and Acacia catechu (Acacia catachu)) It originates from the wood part and bark.

Condensed mimosa tannins are oligomers or polymers composed primarily of flavan-3-ol repeat units shown in Scheme 1, 4-6 or 4-8 linked together, and a smaller proportion of polysaccharides and monosaccharides It is.

  Commercial condensed tannins are generally extracted from bark waste using countercurrent principles in an autoclave. The resulting liquid extract is then concentrated by evaporation and the hot viscous liquid is powdered by spray drying. The spray-dried tannin can absorb 6-8% by weight of water from the atmosphere due to the hydrophilic nature of tannin.

  As used herein, the term “formaldehyde-free tannin-reactive monomer” is used interchangeably with the term “tannin-reactive monomer” and, as shown in Scheme 1, in the presence of an acid catalyst. And refers to a monomer that reacts with the A ring of tannin at the free 5, 6 or 8 site. The tannin reactive monomer disclosed herein excludes formaldehyde.

  As used herein, the term “polyamine” refers to an organic compound having two or more amino groups. Suitable examples of polyamines include, but are not limited to, urea, melamine, and hexamine.

  As used herein, the term “formaldehyde-free polymer phase” means that the polymer phase is formed without the use of formaldehyde as a monomer.

  As used herein, the term “phenol-resole prepolymer” refers to the condensation product of a phenol and a phenol reactive monomer having a reactive methylol group, generally 1 in the presence of a basic catalyst. Prepared in the above molar ratio of phenol reactive monomer to phenol. The phenol used to prepare the phenol-resole prepolymer can be a substituted phenol or an unsubstituted phenol. As used herein, the term “substituted phenol” refers to a molecule containing a phenol reactive site and may contain another substituent or moiety. Exemplary phenols include, but are not limited to, unsubstituted phenol, ethylphenol, p-tertbutylphenol; ortho, meta, and paracresol; resorcinol; catechol; xylenol.

  As used herein, the term “phenol-reactive monomer” refers to any monomer that reacts with the nucleophilic site of phenol. Exemplary phenol reactive monomers include, but are not limited to, formaldehyde, paraformaldehyde, furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, levulinate ester, sugars, 2,5-furande Carboxylic aldehydes, difurfural (DFF) and sorbitol.

  As used herein, the term “tannin-phenol resol mixture” refers to a tannin solution comprising a phenol-resole prepolymer and a volatile substance-free condensed tannin and tannin-reactive monomer dissolved in water. It refers to the composition obtained by mixing.

  As used herein, the term “biologically based foam” is used interchangeably with “biologically based closed cell foam” and is derived from at least one monomer of a resin obtained from a plant. Refers to foam, which contains at least 25% renewable carbon and less than 75% fossil fuel system or petroleum based carbon.

  As used herein, the term “foaming agent” is used interchangeably with the term “foam foaming agent”. In general, the blowing agent must be volatile and inert and can be inorganic or organic.

  As used herein, the term “azeotrope-like” is intended to encompass, in a broad sense, both strictly azeotropic compositions and compositions that behave like azeotropes. The From basic principles, the thermodynamic state of a fluid is defined by pressure, temperature, liquid composition, and vapor composition. An azeotrope is a system of two or more components whose liquid composition and vapor composition are equal at a specified pressure and temperature. In practice, this means that the components of the azeotrope are constant boiling and cannot be separated during a phase change.

  The azeotrope-like compositions of the present disclosure may include additional components that do not form a new azeotrope-like system or that are not in the first distillation fraction. The first distillation fraction is the first fraction taken after the distillation column exhibits steady state operation under total reflux conditions. One way to determine whether the addition of a component forms a new azeotrope-like system so that it is outside the scope of this disclosure is to separate the non-azeotrope into its separate components. Distilling a sample of the composition containing its components under conditions that can be predicted. If the mixture containing further components is non-azeotrope-like, the further components are divided from the azeotrope-like component. If the mixture is azeotrope-like, a limited amount of the first distillation fraction will be obtained that contains all of the mixture components that are constant boiling or behave as a single substance.

  From this, another characteristic of azeotrope-like compositions is that there is a range of compositions containing various proportions of the same components that are azeotrope-like or constant boiling. All such compositions are intended to be encompassed by the terms “azeotrope-like” and “constant boiling”. As an example, it is well known that at different pressures, the composition of a given azeotrope varies at least slightly, as does the boiling point of the composition. Thus, the azeotropes of A and B represent a unique type of relationship, but have a variable composition depending on temperature and / or pressure. Thus, for an azeotrope-like composition, there is a range of compositions that contain various proportions of the same components that are azeotrope-like. All such compositions are intended to be encompassed by the term azeotrope-like as used herein.

  As used herein, the ozone depletion potential (ODP) of a compound is the relative amount of destruction to the ozone layer that the compound can cause, and trichlorofluoromethane (CFC-11) is at an ODP of 1.0. Fixed.

  As used herein, the Global Warming Potential (GWP) as used herein is a relative measure of how much heat a greenhouse gas captures in the atmosphere. Global warming potential is similar to the amount of heat trapped by a particular mass of gas fixed at 1 for all time horizons (20 years, 100 years, and 500 years). Compare with the amount of heat trapped by the mass of carbon dioxide. For example, CFC-11 has 4750 GWP (100 years). Thus, from a global warming perspective, the blowing agent should have zero ODP and the lowest possible GWP.

  As used herein, the term “open cell” refers to individual cells that are ruptured or open or joined together, creating a porous “sponge” foam. Here, the gas (air) phase can move around between the bubbles. As used herein, the term “closed bubbles” refers to discrete individual bubbles, ie, each closed cell is surrounded by a polymeric sidewall that minimizes gas phase flow between the bubbles. . Note that the gas phase is not only trapped inside closed cells but can be dissolved in the polymer phase. Furthermore, the gas composition of the closed cell foam at the time of manufacture does not necessarily correspond to the equilibrium gas composition after aging or sustained use. Therefore, the gas in the closed cell foam often exhibits a composition change when the foam causes a known phenomenon such as an increase in thermal conductivity or a decrease in insulation value due to aging.

  As used herein, the term “closed mold” means a partially closed mold from which some gas can escape or a fully closed mold in which the system is sealed.

Condensed tannin foam A condensed tannin foam formed by foaming and curing a formaldehyde-free foamable composition at a temperature in the range of 50-100 ° C. is disclosed herein and is formaldehyde-free. The foamable composition comprises surface active condensed tannin, formaldehyde-free tannin reactive monomer, water, saturated or unsaturated organic anhydride, foaming agent, acid catalyst, surfactant, and optionally. Polyamines and / or plasticizers. The as-formed condensed tannin-based foam includes a formaldehyde-free polymer phase that defines a plurality of bubbles, the plurality of bubbles including a plurality of open cells and a plurality of closed cells. The as-formed condensed tannin-based foam also includes one or more blowing agents disposed in at least some of the plurality of closed cells formed by the formaldehyde-free polymer phase.

  The formaldehyde-free polymer phase of the condensed tannin foam comprises an acid-catalyzed tannin resin derived from surface active condensed tannin, a formaldehyde-free tannin-reactive monomer, a saturated or unsaturated organic anhydride, and ethoxy A castor oil and optional polyamines and / or plasticizers.

  The surface active condensed tannin of the present disclosure refers to a biologically derived tannin having a surface tension of less than 53.0 mN / m when dissolved in 50% by weight of water, and the amount in weight% units is tannin and water. Based on gross weight. In one embodiment, the surface active condensed tannin is extracted from at least one of mimosa tree, quebraco tree, or pine tree. In one embodiment, the surface active condensed tannin is mimosa tannin extracted from an Acacia mearnsi plant. In another embodiment, the surface active condensed tannin is a volatile material free condensed tannin disclosed hereinabove.

  Although not limited, furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate ester, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF), glycerol, sorbitol Any suitable formaldehyde-free tannin-reactive monomer can be used, including, or mixtures thereof.

  Any suitable saturated or unsaturated organic anhydride may be used including, but not limited to, maleic anhydride, acetic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride and trimellitic anhydride. In one embodiment, the organic anhydride comprises maleic anhydride.

  Any suitable polyamine can be used, including but not limited to urea, melamine, and hexamine. In one embodiment, the polyamine is urea and the organic anhydride is maleic anhydride.

  The acid-catalyzed tannin-based resin can include one or more surfactants with at least ethoxylated castor oil as one of the one or more surfactants.

  One class of suitable surfactants includes nonionic organic surfactants such as condensation products of alkylene oxides such as ethylene oxide, propylene oxide or mixtures thereof with alkylphenols such as nonylphenol, dodecylphenol. Suitable nonionic organic surfactants include, but are not limited to, ethoxylated castor oil available from Lambent Technologies; polysorbate (Tween®) surfactant available from Sigma-Aldrich Chemical Company; BASF Corp. Pluronic® non-ionic surfactant available from (Florham Park, NJ); Tergitol ™; all available from Aldrich Chemical Company, Brij® 98, Brij® 30, And Triton X 100.

  Another class of suitable surfactants includes siloxane-oxyalkylene copolymers such as those containing Si-O-C as well as Si-C bonds. The siloxane-oxyalkylene copolymer can be a block copolymer or a random copolymer. Typical siloxane-oxyalkylene copolymers are siloxane moieties composed of repeating dimethylsiloxy units end-blocked with monomethylsiloxy and / or trimethylsiloxy units, and oxyethylene capped with organic groups such as ethyl groups and / or Contains at least one polyoxyalkylene chain composed of oxypropylene units. Suitable siloxane-oxyalkylene copolymer surfactants include, but are not limited to, a polyether-modified polysiloxane available as Tegostab B8406 from Evonik Goldschmidt Corporation (Hopewell, Va.); Silwet from OSi Specialties (Danbury CT) -77 available (polyalkylene oxide modified heptamethyltrisiloxane.

  The acid catalyzed tannin resin present in the formaldehyde-free polymer phase may contain one or more acid catalysts. Suitable acid catalysts include, but are not limited to, benzene sulfonic acid, para-toluene sulfonic acid, xylene sulfonic acid, naphthalene sulfonic acid, ethyl benzene sulfonic acid, phenol sulfonic acid, sulfuric acid, phosphoric acid, boric acid, hydrochloric acid or theirs. A mixture is mentioned. In one embodiment, the acid catalyst is 2 of additional aromatic sulfonic acids selected from the group consisting of benzene sulfonic acid, para-toluene sulfonic acid, xylene sulfonic acid, naphthalene sulfonic acid, ethyl benzene sulfonic acid and phenol sulfonic acid. Is a mixture of two.

  The formaldehyde-free polymeric phase of the present disclosure that includes an acid-catalyzed tannin-based resin may also include one or more additives. Suitable additives include, but are not limited to, cellulose fiber, bacterial cellulose, sisal fiber, clay, kaolin-type clay, mica, vermiculite, oleagite, hydrotalcite and other inorganic platelet materials, glass fiber, polymer Examples include fibers, alumina fibers, aluminosilicate fibers, carbon fibers, carbon nanofibers, poly-1,3-glucan, lyocell fibers, chitosan, boehmite (AlO.OH), zirconium oxide, or mixtures thereof.

  In one embodiment, the acid-catalyzed tannin-based resin may also include at least one of a polyester polyol or a polyether polyol as an optional plasticizer. The polyester polyol can be formed by the reaction of a polybasic alcohol selected from divalent to pentavalent and a polybasic carboxylic acid. Examples of polybasic carboxylic acids include, but are not limited to, adipic acid, sebacic acid, naphthalene-2,6-dicarboxylic acid, cyclohexane-1,3-dicarboxylic acid, and phthalic acid. Examples of polyhydric alcohols include, but are not limited to, ethylene glycol, propylene diol, propylene glycol, 1,6-hexanediol, 1,4-butanediol, and 1,5-pentanediol. In one embodiment, the plasticizer is an aromatic polyester polyol derived from phthalic anhydride and diethylene glycol. The average molecular weight of the polyester polyol is in the range of 100 to 5,000 g / mol, or 200 to 2,000 g / mol, or 200 to 1000 g / mol. Polyether polyols are made by reacting an epoxide, such as ethylene oxide or propylene oxide, with a multifunctional initiator in the presence of a catalyst, often a strong base such as potassium hydroxide or a bimetallic cyanide catalyst. Is done. Common polyether polyols are polyethylene glycol, polypropylene glycol, and poly (tetramethylene ether) glycol. The average molecular weight of the polyester polyol is in the range of 100 to 5,000 g / mol, or 150 to 2,000 g / mol, or 200 to 1000 g / mol.

  The condensed tannin-based foam disclosed herein above comprising a formaldehyde-free polymeric phase defining a plurality of cells (closed cells and open cells) is disposed in at least a portion of the plurality of closed cells. Also including one or more blowing agents, at least one of the one or more blowing agents is isopentane, isopropyl chloride, 1,1,1,4,4,4-hexafluoro-2-butene and 1- An azeotrope or azeotrope-like mixture with one other blowing agent selected from the group consisting of chloro-3,3,3, -trifluoropropene. In one embodiment, the blowing agent is a mixture of isopentane and isopropyl chloride.

  At least one or more blowing agents have an ozone depletion potential (ODP) of less than 2, or less than 1 or 0, and a global warming potential (GWP) of less than 5000, or less than 1000, or less than 500 . An exemplary blowing agent with zero ODP and low GWP is a mixture of isopentane and isopropyl chloride (0 ODP and less than 20 GWP).

  The condensed tannin-based foam of the present disclosure has an open cell content of less than 15% (or a closed cell content of greater than 85%), or less than 12%, or 10%, as measured according to ASTM D6226-5. Less than or less than 8%.

Further, the condensed tannin-based closed cell foam has an initial thermal conductivity of less than 23 mW / m · K measured at 25 ° C. In one embodiment, the condensed tannin-based closed cell foam has a thermal conductivity with time of less than 25 mW / m · K measured at 25 ° C. The total conductivity of the foam is largely determined by the thermal conductivity of the blowing agent and the open cell content of the foam. This is because the blowing agent placed in at least some of the plurality of closed cells in the low density foam (having a density in the range of 20-45 kg / m ³ ) typically has a total foam volume of up to about 95%. It is for comprising. Thus, only foams that are foamed from a low thermal conductivity foaming agent, including a significant proportion of the foam trapped within the closed cells, resulting in a closed cell structure exhibit a thermal conductivity lower than that of air. Can do. For example, if the open cell content of the low density foam is greater than 90%, the foam mainly comprises air and is 25 mW / m. Thermal conductivity much higher than K. Similarly, mainly closed cell foams (with a closed cell content greater than 90%) will have a thermal conductivity determined by the gas phase thermal conductivity of the blowing agent. For foams with moderate (20-80%) open cell and / or closed cell content, the thermal conductivity of the foam will be determined by the volume fraction and thermal conductivity of the blowing agent.

Condensed tannins based foam has a density in the range of 10~250kg / m ³ or 20 to 50 kg / m ³ or 30-40 kg / m ^3.

  In one embodiment, the condensed tannin-based foam disclosed herein above comprises surface active condensed tannin, furfuryl alcohol, maleic anhydride, urea, ethoxylated castor oil, aromatic sulfonic acid, and isopentane. Derived from a formaldehyde-free foamable composition comprising a mixture of styrene and isopropyl chloride.

  In some various applications where thermal insulation is required, it is desirable for the thermal insulation material to exhibit low flammability as well as low thermal conductivity. The flammability of a material can be evaluated by several different methods known to those skilled in the art. One method is to measure the limiting oxygen index (LOI), which represents the concentration of oxygen required to sustain the flame during combustion of the material (ASTM 2863). . The higher the LOI of the material, the lower the flammability. Therefore, it is desirable for the insulating foam to exhibit as high a LOI as possible. In one embodiment, the disclosed foam or has a limiting oxygen index (LOI) of at least 25 or at least 28 or at least 30.

  Flammability can also be evaluated using a cone calorimeter according to ASTM E1354. Flame properties that can be measured with a cone calorimeter include heat release rate and its peak, mass loss and residual charcoal rate, effective combustion heat and combustion efficiency, ignition time, flame extinction time, and CO and smoke production. Condensed tannin-based foams of the present disclosure that contain maleic anhydride self-extinguish faster than foams that do not contain maleic anhydride. In one embodiment, the condensed tannin foam of the present disclosure containing maleic anhydride self-extinguishes in less than 50 seconds after ignition.

  In addition to the closed cell content, the size of the cells in the foam can also affect the resulting thermal conductivity. In addition to thermal properties, the cell size of the foam can also affect other properties of the foam, such as but not limited to mechanical properties. In general, it is desirable that the foam bubbles be small and uniform. However, for a given density foam, if the cell size becomes too small, the cell wall thickness can become very thin and thus weaken and can burst during the foaming process or in use, so The size cannot be reduced indefinitely. Thus, depending on the density of the foam and its application, there is an optimal size of the bubbles. In one embodiment, the cells, either open cells or closed cells, have an average size in the range of 50-500 μm. In another embodiment, the bubbles have an average size in the range of 50-300 μm, and in yet another embodiment, the bubbles have an average size in the range of 80-200 μm. The cell size can be measured by various methods known to those skilled in the art for evaluating porous materials. In one method, a thin portion of the foam can be cut and subjected to optical or electron microscopy measurements, such as with a Hitachi S2100 scanning electron microscope available from Hitachi instruments (Schaumburg, Ill.).

  In one embodiment, the condensed tannin-based foam disclosed hereinabove is disposed between two similar or different non-foam materials, also referred to as a facer, to form a sandwich panel structure Form. Any suitable material can be used for the face material. In one embodiment, the face material can be formed from metals such as, but not limited to, aluminum and stainless steel. In another embodiment, the facing material may be formed from plywood, cardboard, composite board, oriented strand board, gypsum board, glass fiber board, and other building materials known to those skilled in the art. In another embodiment, the facing material is glass fiber and / or E.I. I. Can be formed from non-woven materials obtained from polymer fibers such as Tyvek® and Typar® available from DuPont de Nemours & Company. In another embodiment, the face material may be formed from woven materials such as canvas and other fabrics. Furthermore, in another embodiment, the surface material may be formed of a polymer film or sheet. Exemplary polymers for the facing material include, but are not limited to, polyethylene, polypropylene, polyester, and polyamide. The thickness of the face material will vary depending on the sandwich panel application. In some cases, the thickness of the surfacing material can be significantly less than the thickness of the foam, while in other cases, the thickness of the surfacing material is equal to or greater than the thickness of the inserted foam. Can be.

  The disclosed condensed tannin-based foam is a bio-derived low density rigid foam having low thermal conductivity over time, low flammability and low water vapor absorption. The disclosed condensed tannin-based foams can be used in a variety of applications including, but not limited to, building exteriors, and insulation of home appliances and industrial equipment. Furthermore, the disclosed condensed tannin-based foams can also be used in combination with other materials such as silica airgel as a support for fragile airgels and potentially as a catalyst support. Potential advantages of the disclosed condensed tannin foam include, but are not limited to, the use of low toxicity materials, zero formaldehyde emissions, improved flame resistance, mold resistance, and antibacterial properties.

Method for Producing Condensed Tannin Foam According to the present disclosure, a method for producing a condensed tannin foam is provided. The method includes forming an aggregate-free solution comprising surface active condensed tannin, a tannin reactive monomer, and water.

  The surface active condensed tannin disclosed hereinabove has a surface tension of less than 53.0 mN / m when dissolved in 50 wt% water. In one embodiment, the surface active condensed tannin is the volatile material free condensed tannin disclosed hereinabove. The amount of dried surface active condensed tannin ranges from 10 to 80%, or 20 to 80%, or 50 to 80% by weight, based on the total weight of the formaldehyde-free foamable composition. .

  Any suitable formaldehyde-free tannin-reactive monomer disclosed hereinabove can be used. The amount of formaldehyde-free tannin-reactive monomer present in the solution is 5 to 80 wt%, or 10 to 50 wt%, or 10 to 30 wt%, based on the total weight of the formaldehyde-free foamable composition Range.

  The step of forming an aggregate-free solution comprises mixing surface active condensed tannin with formaldehyde-free tannin-reactive monomer and water to form a mixture, and providing the mixture with a residence time to provide the tannin. Effectively dissolving the compound in the mixture. At the start of the residence time, the mixture may contain tannin aggregates and a two-phase system can be observed, one phase being tannin aggregates and the other phase being soluble in the monomer. It is a liquid containing tannin and water. As the tannin aggregates dissolve, the mixture becomes more viscous. At the end of the residence time, the mixture is a one-phase system comprising tannin dissolved in the monomer and water. Providing a residence time includes allowing the mixture to stand for the residence time, or mixing the mixture for a period of time, or mixing and leaving for the remainder of the residence time. obtain. The amount of residence time required to obtain an aggregate free solution depends on the temperature at which the tannin is mixed with the monomer and water, as well as the composition and degree of mixing. Any, such as manual mixing, mechanical mixing using a Kitchen-Aid® mixer, twin screw extruder, Brabender, overhead stirrer, ball mill, friction grinder, Waring blender, or combinations thereof Any suitable method can be used to mix the surface active condensed tannin with the tannin reactive monomer and water to form an aggregate free solution.

  In one embodiment, the step of forming an aggregate-free solution comprising surface active condensed tannin, a tannin-reactive monomer, and water comprises first mixing the tannin with water and then the monomer with tannin. Adding to the mixture with water. In another embodiment, the step of forming an aggregate-free solution comprising surface active condensed tannin, a tannin-reactive monomer, and water comprises first mixing tannin with the monomer and then adding water to the tannin. And adding to the monomer mixture. In another embodiment, the step of forming an aggregate-free solution comprising surface active condensed tannin, a tannin reactive monomer, and water comprises mixing the monomer with water and then converting the surface active condensed tannin into water. Adding to the mixture of tannin-reactive monomer and water.

  The method of making a condensed tannin foam also includes the step of adding saturated or unsaturated organic anhydride and blowing agent to the aggregate free solution to form a preform mixture. The method also includes the step of adding an acid catalyst to the preform mixture to form a formaldehyde-free foamable composition.

  The amount of organic anhydride is in the range of 0.5-20%, or 1-15%, or 1-10%, based on the total weight of the formaldehyde-free foamable composition. In one embodiment, the organic anhydride comprises maleic anhydride.

  The process for making the condensed tannin foam is 0.5-20 wt% or 1-10 wt% so that the organic anhydride and polyamine are present in a weight ratio of 1: 0.1-1: 1. And a step of adding the polyamine to an aggregate-free solution, wherein the polyamine comprises at least one of urea and melamine. In one embodiment, the polyamine is urea.

  The amount of blowing agent ranges from 0.5 to 20%, or 1 to 15%, or 1 to 10% by weight, based on the total weight of the formaldehyde-free foamable composition. In one embodiment, the blowing agent consists of isopentane and isopropyl chloride, 1,1,1,4,4,4-hexafluoro-2-butene and 1-chloro-3,3,3, -trifluoropropene. An azeotrope or azeotrope-like mixture with one other blowing agent selected from the group. In another embodiment, the blowing agent comprises a mixture of isopropyl chloride and isopentane present in a weight ratio of 90:10 or 75:25 or 50:50 or 10:90.

  The method for producing the condensed tannin-based foam also includes a step of adding a surfactant to the aggregate-free solution. In another embodiment, a surfactant is added to the preform mixture. The surfactant is first mixed with the blowing agent and then the mixture of blowing agent and surfactant is mixed with the agglomerate-free solution to form a preform mixture. In another embodiment, a surfactant is mixed with the acid catalyst. The amount of surfactant present in at least one of the aggregate-free solution, preform mixture, or formaldehyde-free foamable composition is based on the total weight of the formaldehyde-free foamable composition, It is in the range of 0.5-10 wt%, or 2-8 wt%, or 3-6 wt%.

  The surfactant comprises a formaldehyde-free foamable composition comprising surface active condensed tannins, tannin reactive monomers, saturated or unsaturated organic anhydrides, foaming agents, foamable composition catalysts and optional additives. Present in an amount effective to emulsify. Surfactants are added to reduce surface tension and stabilize the foam cells during the foaming and curing process. In one embodiment, the surfactant is an ethoxylated castor oil disclosed hereinabove.

  The method of making a condensed tannin-based foam further comprises adding the additive disclosed herein above to at least one of the aggregate-free solution or preform mixture. The amount of additive ranges from 5 to 50%, or 10 to 45%, or 15 to 40% by weight, based on the total weight of the aggregate free solution. In one embodiment, the additive is a plasticizer comprising the polyester polyol disclosed hereinabove.

  The amount of acid catalyst disclosed herein above is in the range of 1-20 wt% or 5-20 wt% or 5-15 wt%, based on the total weight of the formaldehyde-free foamable composition. is there. In one embodiment, the acid catalyst is para-toluenesulfonic acid and xylene in a weight ratio ranging from 0.67: 1 to 9: 1, or 2: 1 to 7: 1, or 3: 1 to 5: 1. Contains sulfonic acid. Furthermore, the acid catalyst may be dissolved in a minimum amount of solvent, such as ethylene glycol, 1,2-propylene glycol, triethylene glycol, butyrolactone, dimethyl sulfoxide, N-methyl-2-pyrrolidone, morpholine, 1 , 3-propanediol, or mixtures thereof. Although a catalyst is usually required to produce a foam, in some cases, the foam can be made using thermal aging without a catalyst. A combination of thermal aging and catalyst is commonly used. In some cases, the reaction is exothermic and little or no additional heat may be required.

  A method for producing a condensed tannin-based foam includes foaming a formaldehyde-free foamable composition and curing to dispose a polymer phase that defines a plurality of bubbles, and at least a part of the plurality of bubbles 1 Also included is a step of forming a foam comprising one or more blowing agents. Processing the formaldehyde-free foamable composition includes maintaining the formaldehyde-free foamable composition at an optimum temperature. In one embodiment, the optimum temperature is in the range of 50-100 ° C, or 60-90 ° C. In another embodiment, treating the formaldehyde-free foamable composition comprises foaming the formaldehyde-free foamable composition in a substantially closed mold or continuous foam line. Including the step of In one embodiment, the formaldehyde-free foamable composition is first foamed in an open mold at an optimal temperature in the range of 50-100 ° C, or 60-90 ° C, and then the mold is closed, It is kept at that temperature for a certain time. In some cases, the foam is formed in a closed mold or under application of pressure to control the foam density. Pressures from atmospheric pressure up to 5000 kPa can be applied depending on the desired foam density.

  The method may further include placing the condensed tannin-based foam between two similar or different non-foam materials, also referred to as face materials, to form a sandwich panel structure. Any suitable material can be used for the face material as disclosed hereinabove.

  The facing material can be physically or chemically bonded to the condensed tannin foam to increase the structural integrity of the sandwich panel. Any suitable method can be used for the physical means of bonding, including but not limited to roughening by mechanical means and etching by chemical means. Any suitable method can be used for chemical bonding including, but not limited to, the use of coatings, priming agents, and adhesion promoters that form a tie layer between the surface material surface and the foam.

Method of making a mixed tannin-phenol foam In one aspect,
Volatile-free condensed tannins dissolved in water and tannin reactive monomers,
A phenolic-resole prepolymer derived from phenol and a phenol-reactive monomer and further containing urea; and optionally, a foamable composition comprising a tannin-phenolic resole mixture derived from a saturated or unsaturated organic anhydride There is a mixed tannin-phenol foam formed by foaming and curing.

  Because the tannin reactive monomers of the present teachings exclude formaldehyde, the total amount of formaldehyde in the mixed tannin-phenol foam of the present teachings is less than the phenol-resole prepolymer, thereby reducing the formaldehyde The mixed tannin-phenol foam of the present disclosure is made with improved advantages with respect to exposure and excretion of

  According to the present disclosure, a method for making a mixed tannin-phenol foam is provided. The method begins with 110-200 ° C. or 120-160 ° C. or 125-145 in air, oxygen or nitrogen for 1 to 6 days or 2 to 3 days or 6 to 48 hours or 12 to 24 hours. Forming a volatile substance-free condensed tannin by heating the surface active condensed tannin at a temperature in the range of ℃ to substantially remove one or more volatile compounds having a boiling point above 277 ℃ The process of carrying out is included.

  This method is described herein, except that the aggregate-free tannin solution contains volatile material-free condensed tannin obtained by heat treatment of surface active condensed tannin dissolved in water and tannin-reactive monomer. Further comprising the step of forming an aggregate-free tannin solution as disclosed above. In one embodiment, an aggregate-free tannin solution comprising volatile material-free condensed tannin, furfuryl alcohol and water has a range of 1000-150,000 cP or 2000-100000 cP or 5000-50000 cP at 25 ° C. Has viscosity.

  In one embodiment, the amount of formaldehyde-free tannin-reactive monomer disclosed herein above is the total weight of the tannin solution comprising volatile-free condensed tannin, water, and tannin-reactive monomer. Is present in the aggregate-free tannin solution in the range of 5 to 80% by weight, or 10 to 50% by weight, or 10 to 30% by weight.

  The method of making a mixed tannin-phenol foam is to add 10-90 wt% or 20-80 wt% or 25-70 wt% phenol-resole prepolymer to the tannin solution and add the tannin-phenolresol mixture. The method further includes forming. In one embodiment, the phenol-resole prepolymer is derived from phenol and a phenol reactive monomer and further comprises urea.

  Suitable phenols include, but are not limited to, unsubstituted phenol, ethylphenol, p-tertbutylphenol; ortho, meta, and paracresol; resorcinol; catechol; xylenol.

  Suitable phenol-reactive monomers include, but are not limited to, formaldehyde, paraformaldehyde, furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, levulinate ester, sugars, 2,5-furandicarboxylic acid At least one of aldehyde, difurfural (DFF) and sorbitol is included.

  In one embodiment, the phenol-resole prepolymer is derived from unsubstituted phenol, a phenol reactive monomer and urea and has a number average molecular weight of less than 1500 or less than 1000 and less than 30,000 cPs or 25 at 25 ° C. Having a viscosity of less than 000 cPs.

  In one embodiment, the phenol-resole prepolymer is derived from phenol, formaldehyde, and urea. In another embodiment, the phenol-resole prepolymer comprises phenol, urea, formaldehyde and furfuryl alcohol, furfural, glyoxal, 5-hydroxymethylfurfural, levulinate ester, sugar, 2,5-furandicarboxylic aldehyde, difurfural. Derived from at least one bio-based phenol-reactive monomer selected from the group consisting of (DFF) and sorbitol.

  In one embodiment, the phenol-resole prepolymer is derived from phenol, a phenol reactive monomer, urea.

  The method comprises the steps of adding at least one surfactant, one blowing agent and aromatic sulfonic acid to the tannin-phenol resole mixture, as described for a method of making a condensed tannin foam. In addition, the difference is that a blowing agent, acid catalyst, optional urea, plasticizer is added to the tannin-phenol resole mixture rather than tannin.

  The method involves adding 0.5-20%, or 1-15%, or 1-10% saturated or unsaturated organic anhydride, 0.5-20% by weight polyamine to the tannin-phenol resole mixture. Further steps may be included. The method further includes the step of adding 0.5-20% or 1-15%, or 1-10% by weight blowing agent to form a preformed tannin-phenol resole mixture. The method also includes the step of adding 1-20% by weight acid catalyst to the preformed tannin-phenol resole mixture to form a tannin-phenol resole foamable composition, the amount excluding the weight of the blowing agent. , Based on the total weight of the mixed tannin-phenol foam composition.

  Any suitable blowing agent disclosed herein above may be used. In one embodiment, the blowing agent comprises a mixture of isopropyl chloride and isopentane present in a weight ratio of 90:10 or 75:25 or 50:50 or 10:90.

  In one embodiment, the acid catalyst is para-toluenesulfonic acid and xylene in a weight ratio ranging from 0.67: 1 to 9: 1, or 2: 1 to 7: 1, or 3: 1 to 5: 1. Contains sulfonic acid. In addition, the aromatic sulfonic acid can be dissolved in a minimal amount of solvent, as disclosed hereinabove.

  In one embodiment, the organic anhydride comprises maleic anhydride.

  A method of making a mixed tannin-phenol foam foams and cures a tannin-phenol resole foamable composition at a temperature in the range of 50-100 ° C. or 60-90 ° C. to define a plurality of bubbles. Forming a mixed tannin-phenol foam comprising a polymeric phase, wherein one or more blowing agents are disposed in at least some of the plurality of cells; The step of treating the tannin-phenol resole foamable composition is in a substantially closed mold or continuous, similar to the method for making the condensed tannin foam disclosed hereinabove. Foaming the composition in a foam line or in an open mold.

  In one embodiment, the mixed tannin-phenol foam is a volatile material free condensed tannin, furfuryl alcohol, phenol resole prepolymer, a mixture of isopropyl chloride and isopentane, urea, ethoxylated castor oil based surfactant. Derived from an optional plasticizer comprising an agent, an aromatic sulfonic acid catalyst, and at least one of a polyester polyol or polyether polyol.

  In one embodiment, a method of making a tannin-based foam comprises placing a tannin-based foam between two similar or different non-foam materials, also referred to as face materials, to form a sandwich panel structure. Further included.

  The concepts disclosed herein are further described in the following examples, which do not limit the scope of the disclosure described in the claims. From the above description and these examples, those skilled in the art can ascertain the essential characteristics of the present invention and adapt the present invention to various uses and conditions without departing from the spirit and scope of the present invention. In order to achieve this, various modifications and changes of the present invention can be made.

Test Method Surface Tension The surface tension of the condensed tannin aqueous solution and the resin was measured using a platinum DuNouy ring together with a Cahn DCA-312 Force tensiometer.

Density The apparent density (ρ) of the foam is a) the foam is cut into a regular shape such as a cuboid or cylinder, b) the dimensions and weight of the foam pieces are measured, and c) the foam pieces The volume was evaluated and then measured by dividing the weight of the foam piece by the volume of the foam piece.

More specifically, three cylindrical pieces were used using a brass corer with an inner diameter of 1.651 mm (0.065 inches) to calculate the average apparent density of the test foam. Cut from test foam. The diameter and length of the cylindrical piece were measured using a Vernier caliper, and then the volume (V) of the cylinder was calculated. The mass (m) of each cylindrical piece was measured and used to calculate the apparent density (ρ _a ) of each foam piece.

Open cell content The open cell content of the foam was measured using ASTM standard D6226-5. All measurements were performed at room temperature of 24 ° C.

  The specific gravity bottle density (ρ) of each cylindrical piece was measured at room temperature using nitrogen gas using a gas specific gravity bottle, Model # Accupyc 1330 (Micromeritics Instrument Corporation, Georgia, USA).

AccuPyc works by measuring the amount of gas displaced. The cylindrical foam piece is placed in a density bottle chamber, the pressure when filling the chamber with the test gas is measured, and the test gas is discharged into the second empty chamber, thereby preventing the test gas from accessing the cylinder. The volume (V _s ) of the foam piece was calculated. This measurement was repeated 5 times for each foam cylindrical piece, and the average value of V _s was calculated.

The volume fraction of open cells (O _v ) in the foam sample is expressed by the following formula:
Calculated by

Assuming that the specific gravity of the solid tannin polymer is 1 g / cm ³ , the volume fraction (CW _v ) of the bubble wall is expressed by the following formula:
Calculated from Therefore, the volume fraction of closed cells (C _v ) is _expressed by the following formula:
C _v = 1−O _v −CW _v
Estimated by.

Thermal conductivity The thermal conductivity of the foam was measured using a Hot Disk Model #PPS 2500S (Hot Disk AB, Gothenberg, Sweden).

  The foam whose thermal conductivity needs to be measured is cut into two rectangular or circular specimens of the same size. The lateral dimensions and thickness of the foam pieces needed to exceed 4 times the radius of the Hot Disk heater and sensor coil. The heater and sensor coil radii for all measurements were 6.4 mm, and therefore the lateral dimensions and thickness of the foam pieces exceeded 26 mm.

  Prior to the start of the measurement protocol, the heater and sensor coil are inserted between two test pieces of foam and the entire assembly is secured together so that the foam piece and the surface of the heater and sensor coil are between Close contact was ensured.

  At the start of the test, a known current and voltage were applied to the heater and sensor coil. As the heater and sensor coil were heated by the passage of current through the coil, energy was dissipated to the specimen around the foam. At regular time intervals during the experiment, the resistance of the heater and sensor coil was also measured using a precision Wheatstone bridge equipped on the Hot Disk device. The instantaneous temperature of the coil was estimated using resistance. The temperature history of the heater and sensor coil was then used to calculate the thermal conductivity of the foam using the mathematical analysis detailed in Yi He, Thermochimica Acta 436, pp 122-129, 2005.

  The thermal conductivity measurement on the test piece at room temperature was repeated two more times. Next, the average thermal conductivity of the foam was calculated using the thermal conductivity data.

Thermal conductivity over time The foam is aged in an oven for 4 days at 70 ° C. and then for 2 weeks at 110 ° C., and the thermal conductivity of the aged foam sample is measured at room temperature as described above. It was measured.

Moisture Absorption The water absorption capacity of the tannin-foam was measured as described below: Foam having the dimensions of 3 inches x 2 inches x 1 foot (same as used for thermal conductivity measurements) was convectioned. The sample was dried at 70 ° C. for 16 hours in an oven and the sample weight was measured (W _dry ). The foam was then placed in a controlled room with a constant humidity of 52% and a temperature of 22 ° C. for 24 hours. After 24 hours, measure the weight increase (W _moisture), and the moisture absorption was calculated as follows.

Fire resistance Foam fire resistance is measured using a 6 inch x 1.5 inch x 0.25 inch foam sample, cone calorimeter according to ASTM E1354, and limit oxygen according to ASTM D-2863. Tested using the exponential method.

In the cone calorimeter test, a 100 mm × 100 mm × 13.5 foam sample is exposed to radiant heat with a heat flux of 50 kW / m ² for a minimum of 300 seconds. The average of three specimens for each sample was reported. Parameters tested include ignition time (t _ig ), peak heat release rate (HRR), average HRR after 180 seconds of combustion, effective combustion heat (EHC), total heating value (THR), average mass loss, average smoke production Includes rate (SPR) and CO / CO ₂ generation.

TGA (Thermogravimetric analysis)
Condensed tannin samples were tested in a Q500 TGA manufactured by TA Instruments. The sample was heated from room temperature to 600 ° C. at a heating rate of 10 ° C./min. Samples were tested in duplicate in both air and nitrogen atmospheres.

GC-MS (Gas Chromatography-Mass Spectrometry) Headspace Analysis Instrument: Agilent 7890A gas chromatograph equipped with a 7697A headspace sampler and a 5975C invert XL EI-MSD tabletop mass spectrometer.

Sample preparation and procedure: Evaluate a 50 mg sample in a 20 mL headspace vial and backflush with nitrogen three times in a vacuum oven at room temperature (22 ° C.), quickly capped, and firmly by hand Tightened. Each vial was heated to 200 ° C. for 1 hour, then 1.0 mL of headspace was placed in the GC / MS via a heated sample loop. Two mass spectra were acquired per second. Total ion chromatograms were plotted and peak mass spectra were compared to NIST library spectra.

GC conditions: 30 ° C. for 1 minute, then 15 ° C./minute for 15 minutes to 280 ° C. Run time: 32.67 minutes; Column: Agilent HP-5, 30 m × 0.25 mm, film 0.25 μm; support : He, 0.7 mL / min

Mass spectrometry conditions: Detector; EI mode, source: 230 ° C. MS Quad: 150 ° C., EM voltage: 1612, low mass: 14.0 high mass: 600.0 threshold: 150 samples #: 2 seconds (−1)

Starting materials Unless otherwise indicated, all commercially available materials were used as received. Mimosatannin extract (Acacia mearnsi) samples were obtained from two different sources and used as received. Tannin-A was purchased from SilvaTeam (Italy) and tannin-F was purchased from Tanac (Brazil). Furfuryl alcohol, maleic anhydride, and urea were from Sigma-Aldrich (St. Louis, MO). A phenol-formaldehyde (PF-D) resol prepolymer containing no urea was obtained from DynaChem, Inc. (Westville, IL) and a phenol-formaldehyde (PF-M) resole prepolymer with urea was obtained from Momentary Specialty Chemicals (Mount Jewett, PA). The acid catalyst used is a mixture of 70/30% by weight p-toluenesulfonic acid and xylenesulfonic acid in ethylene glycol or triethylene glycol, and DynaChem Inc. Obtained from The blowing agents used were isopentane and isopropyl chloride (2-chloropropane). The surfactants used were as follows: LUMULSE CO-30Q and LUMULSE CO-40 are ethoxylated castor oils purchased from Lambent Technologies (Gurnee, IL), Tegostab® B8406, Silicone surfactants were purchased from Evonik Goldschmidt Corporation (Hopewell, VA). Stepanol PS-3152 is a commercially available plasticizer purchased from Stepan.

Surface tension of resin solution An tannin aqueous solution was prepared by dissolving tannin extracts (tannin-A and tannin-F) obtained from two different sources in 50 wt% water, and these two different tannins. The surface tension of the extract solution was measured without adding a surfactant. Surface tension data is reported in Table 1.

A tannin solution (tannin-F / FA / H ₂ O) was prepared by dissolving tannin-F in furfuryl alcohol and water. A 50/50 wt% tannin-F / phenol resole solution was prepared by mixing a phenol-formaldehyde based resole (PF-D) and a tannin solution. The surface tension of this 50/50 tannin-F / phenol resole mixture was measured with and without surfactant and compared to 100% resole (Table 1).

As data from Table 1, the tannin-F aqueous solution has a lower surface tension (42.7 mN / m) than the tannin-A solution (53.5 mN / m), indicating that tannin-F is a surface active component. Suggesting that the composition of the two tannins is not identical. Furthermore, the surface tension (61.4 mN / m) of the intact phenolic resole prepolymer was reduced from 61.4 to 54.1 mN / m when the tannin-F solution was added without a surfactant.

Preparation of an aggregate-free stock solution of tannin, furfuryl alcohol and water (tannin / FA / H ₂ O) Furfuryl alcohol (320 g) and deionized water (108.9 g) were mixed in a kettle. Next, tannin-F (571.1 g, containing 7.2 wt% water) was added in portions with frequent stirring to form a solution. The total mass of the kettle was recorded. The kettle was heated to 58-60 ° C. using a heated oil bath and heater in an oil bath equipped with a mixer, and the solution was mixed at 300 rpm for 4 hours. The kettle was then cooled and weighed to measure water loss, additional water corresponding to lost water was added, and the solution was mixed again until the solution was homogenized. The weight ratio of tannin, furfuryl alcohol and water in the solution was 53/32/10. The viscosity of this solution was measured at 25 ° C. and found to be 14,500 cP. Using this stock solution, a foamable composition and a foam were prepared.

Example 1 Preparation of Condensed Tannin Foam in the Presence of Maleic Anhydride A typical preparation of a formaldehyde-free foamable composition and a foaming method for forming a condensed tannin foam are described below. . The actual amount of the various components added and the calculated weight percentage of each component based on the total weight of the foamable composition are reported in Table 2.

  Add a portion of the tannin / FA / water mixture solution, plasticizer (Stepanol PS-3152), surfactant (LUMULSE CO-30Q) and maleic anhydride to a 100 mL beaker, mix well, and in an ice bath Cooled down. To the above solution was added a mixture of isopropyl chloride / isopentane (IPC / IP) (3: 1 weight ratio) to form a preform mixture. The beaker containing the preform mixture was weighed and an additional amount of a 3: 1 mixture of IPC / IP was added to compensate for the amount evaporated during mixing. After the preform mixture is cooled again in an ice bath, a 70/30 mixture of p-toluenesulfonic acid / xylenesulfonic acid (70% solution in ethylene glycol) precooled at −10 ° C. is added for 30 seconds. Thoroughly mixed to form a formaldehyde-free foamable composition.

  About 16 g of as-formed formaldehyde-free foamable composition is quickly transferred from the beaker to an anti-stick paper box mold (3 inches x 3 inches x 3 inches) preheated in an oven at 70 ° C. did. The paper box was inserted into a mold having the same dimensions as the paper box mold and closed tightly. After 30 minutes, the condensed tannin foam was removed from the mold and paper box, placed in another oven, and the foam was post-cured overnight at 70 ° C.

  The properties of the cured condensed tannin foam are reported in Table 2.

Examples 2-3: Preparation of condensed tannin foam in the presence of maleic anhydride Example 1 was repeated except that the amount of maleic anhydride was different. The composition and properties of the as-prepared condensed tannin foam are summarized in Table 2.

Comparative Example A: Preparation of a condensed tannin-based foam in the absence of maleic anhydride using a 75/25 isopropyl chloride / isopentane blend as a blowing agent. Example, except that no maleic anhydride was added 1 was repeated. The composition and properties of the as-prepared condensed tannin foam are summarized in Table 2.

Cured condensed tannin foams (Examples 1-3) from a foamable composition containing maleic anhydride are better compared to foams without maleic anhydride, ie Comparative Example A It is clear from the data in Table 2 that it had a good dimensional stability and a lower open cell content.

  In addition to excellent thermal insulation properties, foams with increased amounts of maleic anhydride were normalized to density and then in air, as shown in FIG. 1, which shows the effect of maleic anhydride on moisture absorption. Reduced the affinity for water present in In general, a foam having a low moisture absorption may have a stable thermal insulation performance.

Examples 4 and 5: Effect of foaming and curing temperature on condensed tannin foam properties Example 1 was repeated as is (Example 4) and at a different foaming and curing temperature of 55 ° C. (Example 5). The composition and properties of the as-prepared condensed tannin foam are summarized in Table 3.

  In general, the higher the cure temperature, the more active the foam foaming process and the faster the cure rate. However, active foam foaming at higher temperatures due to the increased exothermic kinetics of furfuryl alcohol self-polymerization can cause the foam bubbles to become thinner and cause bubble bursts. This can result in a foam having a high open cell content, high thermal conductivity and high moisture absorption. However, the results in Table 3 show the opposite effect, as in Example 4, where the foam cured at 70 ° C. is the same as Example 5 (9.8%) where the foam was cured at 55 ° C. ) With a lower open cell content (6.9%). This can be explained by the faster cross-linking reaction rate between tannin and furfuryl alcohol at higher temperatures, which makes the bubbles more stable, smaller, stronger and made at lower temperatures Compared to the foam produced, it results in a foam having higher closed cells, lower density and lower thermal conductivity.

Examples 6-9: Preparation of Condensed Tannin Foams in the Presence of Maleic Anhydride and Urea Examples 6-9 are shown in Table 4 with varying amounts of urea and maleic anhydride. Example 1 was repeated except that it was used. The properties of the cured foam are reported in Table 4.

Comparative Example B: Preparation of a condensed tannin foam in the presence of urea but in the absence of maleic anhydride, except that no maleic anhydride was added and the amount of urea was 1.5% by weight. Example 6 was repeated. The properties of the cured foam are reported in Table 4.

  When urea was added to a foamable composition containing a tannin-F solution and no maleic anhydride was added, the properties of the cured foam could not be measured due to its poor quality shown by Comparative Example B, It is clear from the data in Table 4. However, when the amount of maleic anhydride was adjusted with respect to the amount of urea, a foam having excellent heat insulating properties was obtained. For example, an effervescent composition containing 0.9 wt% urea, maleic anhydride, when increased in amount from 1.5 to 2.4 wt%, as shown by Examples 6 and 7, Better heat insulation properties were obtained. Similarly, a composition containing 1.7 wt.% Urea, maleic anhydride obtained a lower thermal conductivity at 4.8% than 3.6 wt.%, As demonstrated by Examples 8 and 9. It was. The data suggests that the foam insulation properties can be optimized by adjusting the ratio of maleic anhydride to urea.

Examples 10-11: Thermal conductivity of condensed tannin foam over time Two condensed tannin foams were prepared as described in Example 2. These two foams were aged in an oven at 70 ° C. for 4 days, then at 110 ° C. for 2 weeks, and the thermal conductivity was measured at room temperature, 22.1 and 22.2 mW / m. It turned out to be K.

Example 12 Flame Properties of Condensed Tannin-Based Foam Containing Maleic Anhydride The following components: Tannin / FA / water mixture solution, Stepanol PS-3152 (1.23%), LUMULSE CO-40 (2.16) %), Maleic anhydride (1.5%), a mixture of isopropyl chloride / isopentane (7.36%) and 30% ethylene glycol p-toluenesulfonic acid / xylenesulfonic acid (12.68%) A tannin foam was prepared as described in Example 2 using the / 30 mixture. About 67 g of the composition was poured into a 6 inch × 6 inch × 2 inch mold. The foaming and curing temperatures were 60 ° C and 70 ° C, respectively.

Comparative Example C: An identical foam sample was prepared as described above without maleic anhydride.

  The flame properties of these two foams without face material were tested using a cone calorimeter and the results are reported in Table 5.

  Tannin-based foams containing maleic anhydride self-extinguished in 34 seconds, much faster than foams without maleic anhydride (51 seconds).

Example 13 Flame Properties of Condensed Tannin Foam Containing Maleic Anhydride The following components: Tannin / FA / water mixture solution, Stepanol PS-3152 (1.2%), LUMULSE CO-30Q (2.2 %), 70% of maleic anhydride (0.75%), a mixture of isopropyl chloride / isopentane (7.3%) and p-toluenesulfonic acid / xylenesulfonic acid (12.6%) in 30% ethylene glycol. A tannin-based foam was prepared as described in Example 12 using the / 30 mixture. The composition was foamed and cured in a closed mold having dimensions of 6 inches x 6 inches x 2 inches at 70 ° C.

  Using the limiting oxygen index (LOI) method, the flammability of the foam was measured according to ASTM D-2863, and the LOI value of the tannin-based foam was found to be 31.

  As is apparent from the above description, tannin-foamable compositions containing maleic anhydride have improved dimensional stability, low initial and time thermal conductivity, high closed cell content, lower sensitivity to moisture and urea. And results in a foam having good fire resistance.

Mixed Tannin / Phenol Foam A mixed tannin-phenol foam was prepared using a phenol-formaldehyde (PF-M) resole prepolymer containing urea. The resole prepolymer was characterized and had the following properties:
Number average molecular weight (Mn) = 408
Weight average molecular weight (Mw) = 905
Polydispersity (Mw / Mn) = 2.2
Water (by Karl Fischer) = 12.6%
Residual formaldehyde = 3.94%
Residual phenol = 3.72%
Viscosity at 25 ° C., cP = 7150-7700

Comparative Examples D to G: Preparation of Mixed Tannin-Phenol Foam A typical preparation of a mixed tannin-phenol resole foamable composition and a foaming method for forming a thermoset rigid foam are described below. The The actual amounts of the various ingredients added and the calculated weight percentage of each ingredient relative to the total weight of the composition are reported in Table 6.

  An aggregate-free stock solution of tannin, furfuryl alcohol and water is prepared from commercially available tannin-F using the procedure described hereinabove and is referred to as a tannin / FA / water solution. Add a portion of the tannin / FA / water solution, PF-M resole prepolymer, plasticizer (Stepanol PS-3152), and surfactant (LUMULSE CO-30Q) to a 100 mL beaker and mix well. Cooled in an ice bath. To this solution, an isopropyl chloride / isopentane mixture (IPC / IP) (3: 1 weight ratio) was added in portions and the solution was mixed. The beaker containing the solution was weighed and an additional amount of IPC / IP mixture was added to make up for the amount evaporated during mixing. The mixture was cooled again in an ice bath and then a 70/30 mixture of p-toluenesulfonic acid / xylenesulfonic acid (70% solution in ethylene glycol) pre-cooled at −10 ° C. was added for 30 seconds. Mixed.

  Approximately 16 g of the above solution was quickly transferred from the beaker to an anti-stick paper box mold (3 inch × 3 inch × 3 inch) preheated at 70 ° C. in an oven. The paper box was inserted into a mold having the same dimensions as the paper box mold and closed tightly. After 30 minutes, the foam was removed from the mold and paper box and placed in a separate oven to post cure the foam overnight at 70 ° C. The properties of the cured foam are reported in Table 6.

  In Comparative Examples D and E, tannin-F was used as received and the only difference between these two comparative examples is the amount of surfactant. In Comparative Example F, tannin-F was preheated at 95 ° C. in an oven for 3 days before use. In Comparative Example G, instead of tannin-F, tannin-A was used as received and no plasticizer was added to the composition.

  When comparing the thermal conductivity of the foams described in Comparative Examples D to F with those of Comparative Example G, the thermal insulation performance of the foams prepared from PF-M resole containing tannin-F solution and urea is: It is inferior to the foam prepared from the tannin-A solution, because the composition of tannin-F is different from that of tannin-A and tannin-F interferes with urea present in the PF-M resole. Suggest that it may contain certain chemical species. It is important to note that because the composition of tannin-A differs from tannin-F, the amount of ingredients in the formulation must be adjusted to obtain good results. Comparing Comparative Example D with E, a slight change in surfactant level (2.2 wt% vs. 0.8 wt%) resulted in a foam open cell content (96.4% vs. 19.6%). It should be noted that it had a dramatic impact on it. Furthermore, the use of tannin-F preheated at 95 ° C. for 3 days in the formulation did not affect the thermal insulation performance of the foam (Comparative Example F).

Preparation of Volatile Free Condensed Tannin by Pre-Tanning of Tannin-F 250 g of as-received Tannin-F is placed in a rectangular container with a surface area of 220 cm ² and using a combined nitrogen flow and vacuum. Dry in oven at 130 ° C. for 4 days to wipe out moisture and volatile impurities. After drying, the observed weight loss was found to be 10.92%. The tannin / FA / H ₂ O solution described above was prepared using volatile substance-free condensed tannin-F.

Composition analysis of volatile substance-free condensed tannins Surface tension of tannin-water solution:
Table 7 shows heating a commercially available as-obtained tannin-A and as-obtained tannin-F in 50% by weight aqueous solution and as-obtained tannin-F at 130 ° C. in air for 3 days. The surface tension of volatile substance-free condensed tannin-F obtained by the above is reported.

The data in Table 7 show that tannin-F differs from tannin-A in having a surface active component, and that pre-heat treatment did not remove the surface active component present in the as-received tannin-F. Suggest.

TGA analysis: In order to understand the effect of pre-treatment of tannin-F in air or nitrogen at 130 ° C. on the composition, weight loss experiments were performed in both air and nitrogen atmosphere for the following four samples: (I) as-obtained tannin-A, (ii) as-obtained tannin-F, (iii) volatile-free obtained by heating tannin-F as-obtained at 130 ° C. in air Tannin-F, and (iv) Volatile-free tannin-F obtained by heating tannin-F as obtained at 130 ° C. in nitrogen. Table 8 reports the weight loss of the sample in three temperature ranges: room temperature to 140 ° C, 140-300 ° C and 300-600 ° C.

All four tannin samples lose weight in the region from room temperature (RT) to 140 ° C. in relation to volatile materials, possibly water. Note that both volatile-free tannin-F obtained by preheating tannin-F in air and nitrogen at 130 ° C. trapped moisture from the atmosphere with stirring at ambient temperature prior to TGA analysis. This is very important. This is not surprising because condensed tannins are very hydrophilic in nature. Above 300 ° C., the atmosphere affects the weight loss profile of all samples. All samples under air atmosphere lose 74-75% at 300-600 ° C., mainly by thermal oxidative decomposition, leaving 2.3-3.4% residue at 600 ° C. All samples under N ₂ lost 24-31% at 300-600 ° C., leaving 48-51% residue at 600 ° C., which is due to pyrolysis.

  The most important temperature range for this study was 140-300 ° C. At 140-300 ° C., all samples had similar weight loss in both air and nitrogen, suggesting that this weight loss is due to small molecule volatilization rather than product degradation. ing. However, tannin-F has the most weight loss (17.0-17.2 wt%) in the 140-300 [deg.] C region, followed by tannin-A (15.9-16.2 wt%). Volatile-free tannin-F preheated in nitrogen (13.4 wt%) and volatile-free tannin-F preheated in air (12.2 to 12.9 wt%) Met. Both volatile-free tannin-F samples preheated at 130 ° C. in air and nitrogen have a weight loss of about 3.6 to 4.8% less than untreated tannin-F samples, thereby Suggesting that pre-heat treatment of tannin-F to obtain volatile-free tannin-F results in removal or reduction of volatile components suspected of interfering with urea present in the PF-M resole. Yes. This data also correlates well with foam insulation performance data (see Table 7) obtained from preheated tannin-F samples. Tannin-A had a weight loss (about 16%) close to that of tannin-F (about 17%), but the foam prepared from tannin-A was good in the presence of urea. It has thermal insulation performance (Comparative Example H), which suggests that the composition of tannin-A is different from tannin-F. The higher performance of tannin-A can be attributed to the absence of components that interfere with urea.

Headspace GC-MS Analysis FIGS. 2A and 2B are GC-MS heads for commercial condensed tannin extracts from two different geographic regions: as-obtained tannin-A and as-obtained tannin-F, respectively. The space spectrum is shown. It is surprising to note that tannin-F contains a high boiling volatile component that did not exist in tannin-A (boiling point above 277 ° C. at which resorcinol boils). Volatile components present in tannin-F were identified by matching the mass spectrum with the spectrum of the reference compound in the NIST (National Institute of Standards and Technology) mass spectral library. Their associated GC retention times (minutes) are listed below. It is speculated that the presence of high boiling volatile components in tannin-F may be attributed to the nature of the plant source, the extraction method or any additive added after extraction. From the foam data in FIG. 2B and Table 6, the high boiling volatiles present in Tannin-F (boiling point above 277 ° C.) interfere with the urea present in the resole and the foam is low. It can be concluded that it leads to thermal insulation performance.

  Although the two tannins belong to different regions of the world and their extraction methods may not be the same, the low boiling volatile component (boiling point below 277 ° C.) present in tannin-F is tannin- Note that it also exists in A. Tannin-A did not affect the thermal insulation performance of bio-based foams derived from tannin / PF-M resole mixtures in the presence of urea, so low boiling volatile components have an impact on thermal insulation performance. Not assumed.

Figures 3A, 3B, and 3C show the respective GC- of commercial condensed tannin extracts: as-obtained tannin-F; tannin-F preheated in air; and tannin-F preheated in nitrogen. The MS headspace spectrum is shown. The absence of high boiling volatile components (boiling point above 277 ° C.) is evident in preheated tannin-F samples at 130 ° C., both in air and in nitrogen, and preheated tannin-F samples. The volatility profile is closely consistent with that of tannin-A rather than tannin-F. In order to estimate the amount of highly volatile components reduced during pre-heat treatment, the peak area of resorcinol was measured in the spectra of untreated and pre-heated tannin-F samples. The resorcinol peak area in the untreated tannin-F sample was found to be 3.77 × 10 ⁻⁵ and this peak area was 0 in the heated tannin-F sample, in nitrogen and in air, respectively. .68 and 0.38 × 10 ⁻⁵ , which corresponds to a reduction of 80-90%. Therefore, it can be concluded that the high boiling volatile components were reduced by 80-90% in the heated tannin sample. The heat treatment of tannin-F clearly shows that high boiling volatile components present in tannin-F can be boiled and / or reacted to form non-volatile components. As a result, urea did not affect the preheated tannin, and the foam obtained from the preheated tannin-F had excellent heat insulation performance.

  Volatile components identified in tannin-F as received are methanol (2.252 min), water (1.8-2.8), acetone (3.009), furan (3.042), Methyl acetate (3.387), formic acid (3.693), propanal, 2-methyl- (3.759), 2,3-butanedione (4.151), furan, 2-methylacetic acid (4.337) , Acetic acid (4.749), 2-propanone, 1-hydroxy (5.419), pyridine (6.495), 3 (2H) -furanone, dihydro-2-methyl- (7.311), furfural (7 .703), 2-propanone, 1- (acetyloxy)-or diester (8.015), 4-cyclopentene-1,3-dione (8.413), furan, 2-ethyl-5-methyl- (8 .752), butyro Kuton (8.818), 1,2-cyclopentanedione (8.945), 2,5-furandione, dihydro-3-methylene- (9.124), 2-furancarboxaldehyde, 5-methyl- ( 9.423), 2,4-dihydroxy-2,5-dimethyl-3 (2H) -furan-3-one (9.648), 1H-pyrrole-2-carboxaldehyde (10.02), 2,5 -Dimethyl-4-hydroxy-3 (2H) -furanone (10.252), ethanone, 1- (1H-pyrrol-2-yl)-(10.657), 2-pyrrolidinone (10.737), phenol-2 -Methoxy- (11.09), amine (11.507), 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (11.707), 4H-pyra -4-one, 3,5-dihydroxy-2-methyl (12.085), resorcinol (12.902), phenol, 2,6-dimethoxy- (13.718), dodecane, 1-chloro- (14. 741), C12 alcohol or analogue (14.847), tetradecane, 1-chloro- (16454), C12 alkane or alcohol (16.825), 1-chloro-2-dodecyloxyethane or analogue (16.925). ), Tridecylbenzene isomers (17.967; 18.286), mixed overlapping complex products (18.5-25). Note that the retention time varies with GC conditions such as carrier flow rate and temperature.

Examples 14-17: Preparation of 50/50 Mixed Tannin-Phenol Foam Example 14: Tannin-F was preheated at 130 ° C in air for 3 days to produce volatile-free tannin- F was obtained. A tannin solution (tannin / FA / water) was prepared using volatile material-free tannin-F, furfuryl alcohol and water. Next, a tannin / PF resole mixture was prepared by mixing tannin solution, PF-M resole, plasticizer (Stepanol PS-3152) and surfactant (LUMULSE CO-30Q) in a 100 mL beaker, Cooled in an ice bath. To the above tannin / PF resole mixture, an isopropyl chloride / isopentane mixture (3: 1 weight ratio) was added in portions and mixed. A beaker containing the tannin / PF resole mixture was weighed and an additional amount of isopropyl chloride / isopentane mixture was added to compensate for the amount evaporated during mixing. The mixture was cooled again in an ice bath and then a 70/30 mixture of p-toluenesulfonic acid / xylenesulfonic acid (70% solution in ethylene glycol) pre-cooled at −10 ° C. was added for 30 seconds. Mixed.

  About 16 g of the above solution was quickly transferred from the beaker to an anti-stick paper box mold (3 inch × 3 inch × 3 inch) preheated at 50 ° C. in an oven. The paper box was inserted into a mold having the same dimensions as the paper box mold and closed tightly. After 30 minutes, the bio-based foam in the paper box was removed from the mold and the foam in the paper box was placed in a separate oven and the foam was post-cured overnight at 70 ° C.

  Example 15: In this example, tannin-F was obtained by heating tannin-F for 4 days at 130 ° C. in a nitrogen atmosphere. Example, except that a slightly higher amount of acid catalyst was used in the foam formulation and approximately 67 grams of foamable product was placed in the mold and the foam was molded in a 6 inch x 6 inch x 2 inch mold. A foam was prepared as described in 14.

  Example 16: Acid composition, as described in Example 15, except that 80% acid in 20% triethylene glycol was used in place of 70% acid in 30% ethylene glycol. A foam was prepared.

  Example 17: A foam is prepared as described in Example 16 except that maleic anhydride is added without a plasticizer and the ethoxylated surfactant LUMULSE CO-40 is used in place of LUMULSE CO-30Q. Prepared.

  Composition, process conditions and foam properties are reported in Table 9.

  Comparative Example H: A foam was prepared as described in Example 14 except that both foaming and curing were each carried out at a temperature of 70 ° C. and a higher amount of surfactant was used.

  The data in Table 9 surprisingly shows a foam prepared from commercial tannin-F pretreated at 130 ° C. in air or nitrogen atmosphere for 3-4 days with excellent thermal insulation performance. The thermal conductivity of the foam was significantly reduced from 31 (see Comparative Examples D and E in Table 6) to 22-24 mW / mK and the open cell content of the foam was reduced to less than 10% (or The closed cell content was over 90%).

  Although the temperature and time for heating tannin-F in the pre-heat treatment process was not optimized, the data show that volatile components present in tannin-F reacted (condensed) during pre-heat treatment at 130 ° C or Clearly indicate that it may have evaporated. In addition to the pre-heat treatment of tannin-F, the surfactant level is kept at about 1% by weight for the mixed tannin-phenol resole formulation to obtain a high percentage of closed cells, thereby lowering the initial thermal conductivity. It is also important to obtain a foam having

Thermal conductivity over time of mixed tannin-phenol foam Example 18
A hard mixed tannin-phenol foam was prepared as described in Example 16 and aged in an oven at 70 ° C. for 4 days and then at 110 ° C. for 2 weeks to bring the thermal conductivity to room temperature. And was found to be 23.5 mW / mK.

Example 19
A hard mixed tannin-phenol foam was prepared as described in Example 16, except that no plasticizer was added to the formulation. The foam was aged in an oven at 70 ° C. for 4 days and then at 110 ° C. for 2 weeks and the thermal conductivity was measured at room temperature and found to be 22.8 mW / mK.

  The low thermal conductivity of the aged foams (Examples 18 and 19) indicates their excellent thermal insulation performance.

Example 20: Preparation of Volatile Substance-Free Condensed Tannin-Based Foam By heating tannin-F as obtained in nitrogen at 150 ° C. for 8 hours, volatile substance-free condensed tannin was obtained. Obtained. A tannin solution (tannin / FA / H ₂ O) was prepared as described above using volatile material-free tannin-F, furfuryl alcohol, and water. Volatile-free condensed tannin foam was prepared as described in Example 2 in a 6 ft x 6 ft x 2 ft mold without PF resole. Composition, process conditions and foam properties are reported in Table 10.

Claims (14)

A condensed tannin-based foam,
(A) a formaldehyde-free polymeric phase defining a plurality of open cells and a plurality of closed cells having an open cell content measured in accordance with ASTM D6226-5 of less than 15%,
The formaldehyde-free polymer phase comprises an acid-catalyzed tannin resin derived from surface active condensed tannin, a formaldehyde-free tannin-reactive monomer, a saturated or unsaturated organic anhydride, ethoxylated castor oil, An optional polyamine and / or plasticizer,
The surface active condensed tannin has a surface tension of less than 53.0 mN / m when dissolved in 50% by weight of water;
The formaldehyde-free tannin-reactive monomer is furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural ( DFF), glycerol, sorbitol, or mixtures thereof,
The saturated and unsaturated organic anhydride comprises at least one of maleic anhydride, acetic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride and trimellitic anhydride;
-The polyamine is a formaldehyde-free polymer phase comprising at least one of urea and melamine;
(B) one or more blowing agents disposed in at least some of the plurality of closed cells, wherein at least one of the blowing agents is isopentane, isopropyl chloride, 1,1,1,4,4, 1 an azeotrope or azeotrope-like mixture with one other blowing agent selected from the group consisting of 4-hexafluoro-2-butene and 1-chloro-3,3,3, -trifluoropropene One or more blowing agents,
A condensed tannin-based foam having thermal conductivity with time of less than 25 mW / m · K measured at 25 ° C.   The condensed tannin foam according to claim 1, wherein the organic anhydride and the polyamine are present in a weight ratio of 1: 0.1 to 1: 1.   The condensed tannin foam according to claim 1, wherein the organic anhydride is maleic anhydride and the polyamine is urea.   The condensed tannin foam according to claim 1, wherein the foaming agent is a mixture of isopentane and isopropyl chloride.   The condensed tannin foam according to claim 1, wherein the surface active condensed tannin is extracted from at least one of a mimosa tree, a quebraco tree, or a pine tree.   The surface-active condensed tannin is a volatile substance-free condensed tannin, and the volatile substance-free condensed tannin substantially contains one or more volatile compounds having a boiling point exceeding 277 ° C. The condensed tannin-based foam according to claim 1, which is not present.   Formaldehyde-free foamable composition wherein the foam comprises a mixture of surface active condensed tannin, furfuryl alcohol, maleic anhydride, ethoxylated castor oil, aromatic sulfonic acid, isopentane and isopropyl chloride. The condensed tannin-based foam according to claim 1, which is derived from a product. A method for producing a condensed tannin-based foam,
(A)
10-80 wt% surface active condensed tannin having a surface tension of less than 53.0 mN / m when dissolved in -50 wt% water;
-Furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF), glycerol, sorbitol, or those 5 to 80% by weight of formaldehyde-free tannin-reactive monomer, including the mixture;
Forming an aggregate-free solution comprising 5 to 20% by weight of water;
(B) adding 0.5-20% saturated or unsaturated organic anhydride to the aggregate-free solution;
(C) 0.5-20% by weight of polyamine may be added to the agglomerate-free solution so that the organic anhydride and polyamine are present in a weight ratio of 1: 0.1-1: 1. A step, wherein the polyamine comprises at least one of urea and melamine;
(D) adding 0.5-20% by weight of a blowing agent to the agglomerate-free solution to form a preform mixture;
(E) adding 1-20% by weight of an acid catalyst to the preform mixture to form a formaldehyde-free foamable composition,
0.5-10% by weight of a surfactant is added to at least one of the steps (a), (b), (c), (d), or (e);
The amount in weight percent units based on the total weight of the foamable composition;
(F) foaming the formaldehyde-free foamable composition at a temperature in the range of 50 to 100 ° C. and curing to form a foam containing a formaldehyde-free polymer phase defining a plurality of bubbles. Placing one or more blowing agents in at least a portion of the plurality of bubbles. Before the step of forming an aggregate-free solution,
Heating the surface active condensed tannin in air or nitrogen for a period of about 1 hour to about 6 days at a temperature in the range of 110-200 ° C. to substantially form one or more volatile compounds having a boiling point above 277 ° C. The method of claim 8, further comprising a step comprising:   9. The method of claim 8, further comprising disposing the condensed tannin-based foam between two similar or different non-foam materials, also referred to as face materials, to form a sandwich panel structure.   Condensed tannin foam obtained by the method according to claim 8, wherein the foam has an open cell content measured according to ASTM D6226-5 of less than 15%, A condensed tannin-based foam having thermal conductivity with time of less than 25 mW / m · K, as measured by A method of making a mixed tannin-phenol foam comprising:
a) Heating the surface active condensed tannin in air or nitrogen for a period of 2 to 48 hours at a temperature in the range of 110 to 200 ° C. to substantially add one or more volatile compounds having a boiling point above 277 ° C. And thereby forming a volatile substance-free condensed tannin, wherein the surface active condensed tannin is dissolved in 50% by weight of water and has a surface of less than 53.0 mN / m A step having tension;
b)
-10 to 80% by weight of volatile substance-free condensed tannin,
-Furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, acrolein, levulinate, saccharides, 2,5-furandicarboxylic aldehyde, difurfural (DFF), glycerol, sorbitol, or those 5 to 80% by weight of formaldehyde-free tannin-reactive monomer, including the mixture;
Forming an aggregate-free tannin solution comprising 5 to 20% by weight of water;
c) adding 10-90% by weight of a phenol-resole prepolymer to the tannin solution of step (b) to form a tannin-phenol resole mixture,
The phenol-resole prepolymer is derived from phenol and a phenol reactive monomer and further comprises urea;
The phenol reactive monomer is formaldehyde, paraformaldehyde, furfuryl alcohol, furfural, glyoxal, acetaldehyde, glutaraldehyde, 5-hydroxymethylfurfural, levulinate ester, saccharides, 2,5-furandicarboxylic aldehyde, difurfural ( DFF) and at least one of sorbitol,
d) adding at least one blowing agent to the tannin-phenol resol mixture;
e) 0.5-20% saturated or unsaturated organic anhydride,
A step that may be added to the tannin-phenol resol mixture;
f) 1-20% by weight of polyamine may be added to the tannin-phenol resol mixture;
g) adding 0.5-20% by weight of a blowing agent to the tannin-phenol resol mixture to form a preformed tannin-phenol resol mixture;
h) adding 1-20% by weight of an acid catalyst to the preformed tannin-phenol resole mixture to form a tannin-phenol resole foamable composition;
i) adding 0.5-1.5% by weight of a surfactant to at least one of the steps (b)-(h),
The amount in weight percent units based on the total weight of the tannin-phenol resol foamable composition;
j) foaming and curing the tannin-phenol resole foamable composition at a temperature in the range of 50-100 ° C. to form a mixed tannin-phenol foam comprising a polymeric phase defining a plurality of cells; And wherein one or more blowing agents are disposed in at least some of the plurality of bubbles.   13. The method of claim 12, further comprising disposing the condensed tannin-based foam between two similar or different non-foam materials, also referred to as face materials, to form a sandwich panel structure.   13. Mixed tannin-phenol foam obtained by the method of claim 12, wherein the mixed tannin-phenol foam is measured at 25 ° C. with a thermal conductivity of less than 25 mW / m · K. Foam.