JPS612723A - Manufacture of foam - Google Patents

Abstract

PURPOSE:To obtain a highly air-permeable foam free from surface skin, by mold injection, at a specific packing rate, of a stock solution prepared by regulating the final density after expansion of a blend of organic polyisocyanate and a specific polyol in the presence of specific catalyst, foam stabilizer and foaming agent. CONSTITUTION:A blend comprising (A) an organic polyisocyanate and (B) a polyol at least part of which is a polymer from ethylenic unsaturated monomer and polyether (or polyester) polyol is subjected, in the presence of (1) as a catalyst, 0.02-0.2pts.wt. per 100pts.wt. of said polyol, of a tertiary amine, a resinification promotor and 0.2-0.9pts.wt. of a second tertiary amine, a foaming accelerator, (2) as a foam stabilizer, a silicone compound of formula (A is polyoxyethylene with an average molecular weight 100-700, etc.; x is 3-20; y is 3-30; R is H, etc.), and (3) a foaming agent, to expansion in a mold (with injection at a packing rate 120-300% of the stock solution capable of providing the final density 0.02-0.04g/cm<3> after free expansion, made up of the above components and ingredients), thus obtaining the objective foam.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for producing polyurethane foam, and more specifically to a skinless polyurethane foam that is useful as a filter material with good air permeability without a surface skin or cell membrane. The present invention relates to a method for producing polyurethane mold foam.

[Prior art]

Conventionally, methods for obtaining skinless polyurethane mold foam have been proposed such as (1) using a special mold release agent, (2) molding at a high temperature, and (3) using a foam-breaking agent. However, with method (1), a strong surface skin is formed in some areas, and even with alkaline aqueous solution treatment, the surface skin and cell membrane cannot be removed sufficiently, and when the alkaline aqueous solution treatment time is prolonged, the cell skeleton collapses and the shape of the foam is lost. disappear,
Method (2) causes cell collapse and results in a foam that has no trapping ability as a filter, and method (3) has drawbacks such as easy formation of a skin on the surface, making it difficult to use as a filter or a filter with good air permeability. This method is not satisfactory as a method for obtaining the above.

[Purpose of the invention]

The present invention aims to provide a skinless polyurethane mold form that has good air permeability and excellent filter function.

[Structure of the invention]

The present invention provides a method for producing polyurethane foam by mold foaming an organic polyisocyanate and a polyol in the presence of a foam stabilizer, a catalyst, and a blowing agent. As at least part of the Jol, a polymer polyol (A) from an ethylenically unsaturated monomer and a polyether polyol and/or a polyester polyol, or (7! and a polyether polyol f
B) using (2) 100 parts of polyol as a catalyst, o02~
Tertiary amine and hydrogen that promote the resin formation reaction of the 02 part
Using a tertiary amine that promotes the foaming reaction of 09 parts, (3
) As a foam stabilizer, a compound of the general formula [wherein A represents a polyoxine ethylene and/or oxypropylene chain of average publication I00 to 700, and X is 3
~20, y represents 3 to 30, and R represents H and/or an alkyl group having 1 to 5 carbon atoms and/or an acyl group. (However, the dimethylsiloxane units and the polyoxyalkylene noroxane units may be randomly arranged.)] (4) Free foam density 0.02 to 0, oJ/ This is a method for producing skinless polyurethane foam, which is characterized by injecting a foam stock solution that provides crd into a fi(-) with a pack rate of 120 to 300 inches.

Polyether polyol and polyester polyol, which are raw materials for the polymer polyol (A) used in the present invention, are both commonly used as raw materials for polyurethane. 1. As polyester polyols, those C(B) and (C1) described below can be used. These can be used alone or as a mixture, and they may be mixed with a small amount (usually 20% by weight or less of the total amount of polyol) of a low-molecular polyol (described later) for use in producing a polymer polyol.

The ethylenically unsaturated monomer (b) used in the production of the polymer polyol-w (Al) used in the present invention is
The following may be mentioned: (1) Acrylic acid, methacrylic acid and derivatives thereof: acrylonitrile, methacrylonitrile.

Acrylic acid, methacrylic acid and their salts.

Methyl acrylate/l/, methacrylic acid) LA, dimethylaminoethyl methacrylate, acrylic amide, methacrylic amide, etc.

(11) Aromatic vinyl monomers, styrene, α-methylstyrene, etc.

(ti11 olefinic carbide ice hydrocarbon monomer lene, propylene, butadiene, isobutylene, isoprene, 1
, 4-pentagenato.

(Iv) Vinyl ester monomer: vinyl acetate, etc.

M Vinyl halide monomers: vinyl chloride, vinylidene chloride, etc. Vinyl ether monomers: vinyl methyl ether, etc.

Among these, preferred is acrylonitrile.

These are methyl methacrylate, styrene, and butadiene. Particularly preferred are acrylonitrile, a combination of azilonitrile and styrene (styrene:acrylonitrile weight ratio of 10:90 to 60:40).

The proportion of polyol (polyether polyol and/or polyester polyol and, if necessary, low-molecular-weight polyol) and monomer in the polymer polyol fA) can be varied over a wide range, but usually the ethylenically unsaturated monomer is The amount of polymer (or polymer) is 2 to 70 parts by weight, preferably 5 to 40 parts by weight.

The production of polymer polyols from polyols and ethylenically unsaturated monomers can be carried out by conventional methods. Polymerization of ethylenically unsaturated monomers in Datoage Polyol-ρ (
A method of polymerizing in the presence of a radical generator (such as a radical generator) (US Pat. No. 8,888,851).

Special Publication No. 89-24'187, Special Publication No. 47-47999
No. 50-15894) and a method of graft polymerizing a polymer obtained by prepolymerizing the above monomers with polyol in the presence of a radical generator (Japanese Patent Publication No. 47-1989)
7597). The former method is preferred. As the polymerization catalyst (radical generator) used in the polymerization reaction, azo compounds, peroxides, persulfates, perborates, etc. can be used, but azo compounds are preferred in practical terms. The amount used is not particularly limited, and for example, 0.00 parts by weight per 100 parts by weight of ethylenically unsaturated monomer (or polymer).
The amount is 1 to 20 parts by weight, preferably 01 to 15 parts by weight. The above polymerization can also be carried out in the presence of a solvent such as toluene, xylene and the like. The reaction temperature is usually 50-1? O
0% preferably 90-150°C.

In the present invention, the polyether polyol (Bl) used in combination with the polymer polyol (A) is a polyfunctional compound containing an active hydrogen atom such as a polyhydric alcohol, a polyhydric phenol, a polycarboxylic acid, or an amine compound, and an alkylene oxide. Examples of the polyhydric alcohols include ethylene glycol, propylene glycol, 1.4-butanedio-t&, 1.6-
Dihydric alcohols such as hexanediol, diethylene glycol, and neopentyl glycol; trihydric alcohols such as glycerin and trimethylolpropane; tetrahydric or higher alcohols such as pentaerythritol, sorbitol, and sucrose; polyhydric phenols include pyrogallol, hydroquinone, etc. In addition to polyhydric phenols, bisphenols such as bisphenol A, novolak resins having two or more phenolic hydroxyl groups, intermediates of resol resins, etc.; polycarboxylic acids include aliphatic polycarboxylic acids such as succinic acid and adipic acid, Phthalic acid, terephthalic acid,
Aromatic polycarboxylic acids such as trimellitic acid can be used. Examples of amine compounds include monoamines such as ammonia and butylamine; aliphatic polyamines such as ethylenediamine, hexamethylenediamine, and diethylenetriamine; alicyclic polyamines such as cyclohexylenediamine and isophoronediamine; phenylenediamine,
Aromatic polyamines such as tolylene diamine, xylene diamine, diphenylmethane diamine, polyphenylmethane polyamine, diethyl tolylene diamine; heterocyclic polyamines such as piperazine, N-aminoethylpiperazine; and monoethanolamine, jetanolamine, Examples include alkanolamines such as triethanolamine. Two or more kinds of the above-mentioned active hydrogen atom-containing compounds can also be used. Examples of the alkylene oxide to be added to the active hydrogen atom-containing compound include ethylene oxide, propylene oxide, butylene oxide, heavy tetrahydrofuran, styrene oxide, and epichlorohydrin. The alkylene oxides may be used alone or in combination of two or more, and in the latter case, block addition, random addition, or a mixture of both may be used. Among these alkylene oxides, propylene oxide and/or ethylene oxide are preferred, but depending on the required performance, a small amount of other alkylene oxides (butylene oxide, tetrahydrofuran, styrene oxide, etc.) may be used in combination with these. It's okay. From the viewpoint of reactivity, a combination system of propylene oxide and ethylene oxide (usually 70:80 by weight) is preferable.
~95:5, especially 80:20~90:10]. Addition of alkylene oxide can be carried out in the usual manner, either without catalyst or in the presence of a catalyst (alkaline catalyst, amine catalyst, acid catalyst) (particularly in the latter stages of alkylene oxide addition) at normal pressure. or carried out under pressure.

The OH value of polyether polyol (B) is usually 10 to 7.
0, preferably 20-50. If the OH number is less than 10, the foam becomes too soft, resulting in poor shape retention of the molded product, and if the OH number is 70 or more, there are many skins and cell membranes on the surface of the ζ mold, resulting in a foam with poor air permeability. The (average) number of functional groups in (B) is usually 2 to 8, preferably 2 to 4.

Among (B), preferred are those having an oxyethylene chain at the end [chip type, balanced type, random chip type (having a random polyoxyethylene/oxypropylene chain inside)].

The terminal oxyethylene group content is usually 5 or more (weight% downward), preferably 5 to 80, more preferably 1
(1 to 20%. If the oxyethylene chain content is less than 5%, curing immediately before the end of foaming is insufficient and the potash and foam collapse. The total oxyethylene group content is usually 5 to 5%.
It is preferably 10 to 30%.

In the present invention, a polymer polyol (7!, or (A) and a polyether (B) are used as at least a part of the polyol, but when both are used in combination (Al and (
The ratio (weight ratio) with I3) is preferably 70:80.
~20:8Q, more preferably 60:40-80
: 70°, particularly preferably 50: 50-40
: 60.

In the present invention, in addition to these polyols [(A), or (A) and (B)], if necessary, other polyols such as polyester) v polyols (Q1 low-molecular polyol, low-molecular polyamine (El) are used in combination) can do.

Examples of polyester polyol-W (C) include ring-opening of condensed polyester polyols and lactones obtained by reacting low-molecular-weight polyol-V (or polyether polyol) with dicarboxylic acid (or dicarboxylic acid anhydride and alkylene oxide). Examples include polyether polyols obtained by polymerization. Examples of the low-molecular polyols include ethylene glycol, propylene glycol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, bis(hydroxymethy)V)cyclohexane, bis(hydroxymethy/L/
) Diols such as benzene; trimethylolpropane, glycerin, etc., and mixtures thereof.

Examples of dicarboxylic acids include conolic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, terephthalic acid, dimer acid, and mixtures thereof. Examples of the lactone include ε-caprolactone. (Of q, the terminal is preferably first-class O
H and is liquid at room temperature. From the viewpoint of workability, polyether polyols are preferable ◎ As the low molecular polyols (D), the above [: (B),
[mentioned as raw materials for (C)] dihydric alcohol, polyhydric alcohol (trihydric or higher) (glycerin, etc.), alkanolamines (triethanolamine, jetanolamine, etc.), and low molecular weight polyols with a molecular weight of 600 or less. Examples include those commonly used as chain extenders and crosslinking agents such as ether polyols.

Low-molecular polyamines (typical examples include aliphatic, alicyclic, aromatic, and heterocyclic polyamines listed above as raw materials for (B)).

The proportion of (A) in the total amount of polyol is usually 20% or more, preferably 30 to 70%, more preferably 40 to 50%.
It is Chi. If (A) is less than 20 inches, the cell membrane and surface skin of the foam will increase. Moreover, if the thickness exceeds 70 inches, the cells of the foam partially collapse, which is not preferable. The proportion of (B) in the total amount of polyol is preferably 30 to 80%
More preferably 40 to 70 inches, particularly preferably 50 to 70 inches
It's 60 inches. (The ratio of q is usually 50% or less, preferably 30% or less, and the ratio of (D) (including the amount if a low-molecular polyol is used in conjunction with the production of the polymer polyol) is usually 20% or less, preferably is less than 10%. (
The average amount is usually 5% or less, preferably 3% or less.

The proportion of the polymer portion in (A) contained in the total amount of polyol is usually 5 to 40%, preferably 10 to 20%.

Entire polyol [(N polyol part and (B))]
The terminal oxyethylene group content (average) is 5 or more (5 to
30%) 10 to 20 inches is particularly preferred.

The tertiary amines used as catalysts in the present invention to promote the resin formation reaction include those effective as catalysts for the reaction with alcoholic isocyanates, such as triethylenediamine, tetramethylethylenediamine, tetramethylhexylenediamine, 1. 8-Diaza-bicyclo[5
, 4,0] undecene-7, dimethylaminopropylaquine, and organic acid salts thereof. Preferred is triethylenediamine.

Tertiary amines that promote the foaming reaction include those effective as catalysts for the reaction between water and isocyanate, such as N-
Examples include methylmorpholine, N-ethylmorpholine, triethylamine, diethylethanolamine, diethylethanolamine, and the like. Preferred is N-ethylmorpholine.

The amount of the resin conversion catalyst used is usually 0.02 to 0.2 parts, preferably 0.05 to 0.01 parts per 100 parts (by weight, hereinafter the same) of polyol/I. If the amount is less than 0.02 parts, the resin formation reaction will be slow and curing will take a long time. If the amount exceeds 102 parts, the surface skin of the mold foam tends to form and the air permeability deteriorates.6 The amount of the foaming catalyst is usually 0.2 to 0.9 parts, preferably 0.4 to 0.6 parts per 100 parts of polyol. 0
If the amount is less than 2 parts, foaming will be slow and the mold foam will have more surface skin. If the amount is more than 0.9 parts, foaming will be too fast,
Form cells become fine and air permeability deteriorates. The ratio of resin forming catalyst to foaming catalyst is usually 8:97 to 50:5.
0, preferably 10:90 to 20:80.

The total amount of both is usually 0.8 to 100 parts of polyol.
There are 10 copies. The amount of catalyst used is preferably such as to provide a longer curing time, for example 15 to 60 minutes, than for ordinary urethane foams.

In the general formula (1) of the foam stabilizer used in the present invention, common alkyl groups include methyl, ethyl, n- and l-propyl, and butyl; acyl groups include acetyl,
Examples include propionyl, butyryl, and valeryl.

In the general formula (1), examples of A include a polyoxine ethylene chain, a polyoxypropylene chain, and a polyoxyethylene oxypropylene chain.

Among these, polyoxyethylene oxypropylene chains, especially those containing oxypropylene groups as main group (oxypropylene/oxyethylene weight ratio 50:50-9
9:1, more preferably 80:20 to 99:1).

As the silicone foam stabilizer represented by the general formula (1) used in the present invention, a polyoxyalkylene siloxane copolymer soluble in the above polyol is suitable.

L-5809 (product name of Nippon Unicar■) % B-5
246 (product name of Goldschmidt ■), 5H-19
8,5RX-2740 (trade name of Toray Silicone ■)
can be mentioned. The silicone foam stabilizer is polyol.
/L/100 parts usually 05-1.5 preferably 0
A range of 6 to 10 parts is used. If the amount is less than 0.5 part, it may cause cell roughness in the resulting mold form.
When the amount is more than 5 parts, the surface skin of the mold form becomes extremely large.

As the organic polyisocyanate used in the present invention, those conventionally used in the production of polyurethane can be used. For example, aliphatic polyisocyanates (hexamethylene diisocyanate.

lysine diisocyanate, etc.), alicyclic polyisolysocyanates (tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthylene diisocyanate, quinlylene diisocyanate, etc.), and mixtures thereof. Among these, aromatic diisocyanates are preferred, and TDI and MDI are particularly preferred. These polyisocyanates are crude polyisocyanates such as crude T
DI) Phosgene compound of crude MDI (crude diaminodiphenylmethane (a mixture of diaminodiphenylmethane, a condensation product of formaldehyde and an aromatic amine or a mixture thereof, and a small amount (for example, 5 to 20% by weight) of a trifunctional or higher functional polyamine): (boriyal polyisocyanate)
(PAPI) ). Alternatively, modified polyisocyanates such as liquefied MDI (carposiimide modified, trihydrocarbyl phosphate modified, etc.) or excess polyisocyanates (TDI, MD, etc.)
It can also be used as a free isonanate-containing prepolymer obtained by reacting a polyol with a polyol, or they can be used in combination (for example, a modified polyisocyanate and a prepolymer are used together). The polyols used in the production of the above prepolymer usually have an equivalent weight of 30 to 200, such as glycols such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol; triols such as trimethylolpropane and glycerin; and high-functionality polyols such as pentaerythritol and sorbitol. and alkylene oxide (ethylene oxide and/or propylene oxide) adducts thereof. Among these, those having 2 to 3 functional groups are preferred. The content of free isocyanate groups in the above-mentioned modified polyisocyanates and prepolymers is usually 10 to 30%, preferably 15 to 30%, and particularly preferably 20 to 80%. Among the organic polyisocyanates, a mixture of TDI and crude MDI (weight ratio, for example, 95:5 to 80:70, preferably 90:10 to 50:50) is preferred.

As the blowing agent, water and/or a halogen-substituted aliphatic hydrocarbon blowing agent (fluorocarbons such as trichloromonofluoromethane) can be used. Preferred is water.

In the present invention, the free foam density is 002 to 0.04.
The amount of blowing agent used is adjusted so that it falls within the range of 9/Cd. If the free foam density is less than 0.02 g/Cd, the foam will become rough when molded into one mold form, and if it is higher than o, o41//crl, a strong surface skin will increase on the mold surface.

The amount of foam stock solution injected into the mold is adjusted so that the pack rate (excess filling rate) is 120 to 800%. That is, an amount 12 to 3 times the minimum required amount of foam stock solution (injection i in the case of free foaming) calculated from the time of injection into the mold is injected. If the packing ratio is less than 120 inches, the mold form will become rough and the cells will collapse. If the pack rate exceeds 300 cm, the cells in the mold form will be fine, resulting in a strong cell membrane, a large surface skin, poor air permeability, and rapid foaming, and too much foaming pressure, which will significantly reduce workability during mold injection. . (Also pigments if necessary)
Fillers) Flame retardants 1, thixotropic agents, etc. can also be added to the foam stock solution.

In the present invention, the foam can be generally produced using a no-mold foaming technique. For example, polyol is mixed with a foaming agent, a catalyst, a foam stabilizer, etc. to form liquid A, and liquid B is prepared in advance with an organic isocyanate, which is then filled into a tank of a low-pressure foaming machine. Inject liquid A and liquid B into the open mold using the migging head, tighten the lid, and after foaming is completed,
Place in a curing oven at 150°C and remove from the mold after curing. Isocyanate index is usually 70-120, preferably 80-120
It is 110.

The surface skin and cell membrane of the obtained foam can be completely removed by treatment with an alkaline aqueous solution or a combustion method, if necessary. As an alkali, NaOH,
An example is KOH. The concentration of the aqueous solution is usually between 20 and 50. Alkaline aqueous solution treatment can be carried out using conventional methods and conditions. For example, the mold form is 80-90
The film is removed by immersing it in a 30% alkaline aqueous solution at ℃ for 15 to 20 hours.

Examples of the combustion gas used in the combustion method include a mixed gas of propane, butane, etc. and oxygen. The mixing ratio (weight ratio) of propane and oxygen is usually 5:95 to 15:85. Film removal using the combustion method can be performed under generally known methods and conditions.

For example, if the foam is placed in a sealed container, the temperature will be approximately 400 Hg.
After reducing the pressure to 760 Hg, a mixed gas of 93% oxygen and propane was added, and the mixture was ignited and burned to remove the film.

〔Effect of the invention〕

The manufacturing method of the present invention is clearly superior to conventional manufacturing methods in the following respects.

(11) By using the polyoxyalkylene siloxane of the present invention and using the 8th-class amine that promotes the resin-forming reaction and the tertiary amine catalyst that promotes the foaming reaction within the range, gas release in the foam cell immediately before the end of foaming can be achieved. The cell film and surface skin of the mold form can be removed, resulting in a foam with good air permeability.

(2) In the conventional foaming method similar to the present invention, the agitation speed of the foaming machine is lowered to form a strong cell membrane and surface skin with a thick cell skeleton when forming a large cell foam. If carried out using the raw materials and conditions specified in the invention, a skinless molded foam with a thin cell skeleton, few cell membranes, and few surface skins can be obtained.

(3) Compared to conventional foam, the cells are aligned, and when used as a filter, there is less pressure loss and the collection effect is excellent.

The molded foam obtained by the present invention is useful as a cushioning material for automobiles, furniture, etc.; and the foam treated with an alkaline aqueous solution to remove the surface skin and cell membrane is useful as a filter, etc.

Furthermore, the skinless foams f, t, and
By containing and adhering adsorbents such as activated carbon, zeolite (molecular sheep), activated alumina, activated bauxite, activated clay, silica gel, bone charcoal, etc. on the surface and/or inside (for example, the method described in JP-A-55-99819). ), it can be useful as a fill material for adsorbing and removing bad odors for automobiles, and as a filter material for industrial adsorption and deodorization. Furthermore, the skinless foam according to the present invention may be made of powdery inorganic materials such as metal materials with catalytic performance (Cu, Fe, Co, Ni,
Pd, Pt, Rh.

Supports containing Mn, V, Zn, Ce, Or, Mo, Ti f (and their oxides, etc.), ceramic materials (based on silica, alumina, magnenoir, especially cordierite) By depositing, firing, and sintering, it is possible to produce porous inorganic materials and ceramics useful for applications such as catalysts, catalytic reaction fillers, catalyst supports, heat-resistant filters, chemical-resistant filters, molten metal filters, gas diffusers, and fluid mixers. foam can be manufactured. As for the manufacturing method and structure of ceramic foam, for example, Japanese Patent Application Laid-open No. 55
-24585, JP 55-111817, JP 58-161962, JP 58-91048, and JP 58-151882,
Ceramic raw material [Mixed powder containing MgO, Al, O5, Sio2 that becomes cordierite composition by firing or cordierite powder (the above mixed powder is heated and powdered into cordierite ceramic) or a mixture of both Polyurethane foam is impregnated with a slurry of nihinder (methylcellulose, ethylcellulose, polyvinyl alcohol, polyvinyl butyral, etc.), water, etc., dried and fired (preferably 1300-1500
00° C. for 5 to 6 hours) to obtain a ceramic foam.

〔Example〕

The manufacturing method of the present invention will be specifically explained below using Examples. Note that in the examples, parts and q are parts by weight and weight %.
represents.

Example 1 Polyether polyol (lB) 5 with a molecular weight of 5000, which was obtained by addition polymerizing 4258 j;l of propylene oxide to glycerin 929 and further addition polymerizing 650 g of ethylene oxide.
0 parts, Polymer polyol/I/(A) 50 in which 20 parts of acrylonitrile were polymerized based on this polyol
27 parts of water, 0.1 part of triethylenediamine, 03 parts of N-ethylmorpholine, foam stabilizer B-5246 (
Add 80 parts of TDI-80 and Crude MDI to the premix with 075 parts of Gold'n Umit ■:
Add 36 parts of blended isocyanate to 11
After stirring and mixing for 10 seconds using 000RP NOSHED, the mixture was poured into a mold (30 x 80 x 5 m, made by M) with a 15 mm diameter vent hole adjusted to a mold temperature of 50°C, the lid was closed, and foaming was performed within the mold. After 3 minutes had passed after the completion of foaming, the product was cured at 100° C. for 30 to 45 minutes.

The obtained foam was examined for the amount of surface skin cell film, air permeability, and general mechanical properties using the following evaluation methods.

(Method for evaluating foam) 49 Area of surface skin When the area of the surface of the mold form is taken as 100, the area of the skin is indicated by a circle. The smaller the area of the surface skin, the better the air permeability of the foam.

B. Amount of cell membrane: Cut the mold form, observe the state of the cells on the cut surface with a magnifying glass, and count how many cells with cell membranes are present within a length of 10α. The smaller the amount of cell membrane, the better the air permeability and the smaller the pressure loss when used as a single filter, making it an excellent foam.

C. Alkali treatment time: Obtained mold Formra 8
The time taken for the surface skin cell film to completely disappear after immersion in a 30% alkaline aqueous solution at 0 to 120°C is shown.

The shorter the processing time, the easier it is to obtain a skinless mold form that is completely free of surface skins and cell membranes.

D0 Mechanical properties: Examine tensile strength, elongation, tear strength, compressive strength, permanent set, air permeability, etc. A mold form with excellent mechanical strength is suitable as a cushioning material.

E. Internal collapse of cells: The mold form was cut and the state of the internal cells was observed. When the cell skeleton collapsed and several cells joined together, it was determined that there was cell collapse.

The results of the evaluation test are shown in Table 3.

Examples 2 to 7, Comparative Examples 1 to 6 Blending ratio of polymer polyol/L/(A) and polyether polyol (Bl), water, amount of catalyst (triethylenediamine, N-ethylmorpholine), foam stabilizer The same procedure as in Example 1 was carried out except that the s class or the overback rate were changed, respectively.

Foaming prescription and evaluation results are shown in Tables 1 and 2 and Tables 3 and 4, respectively.
Shown below.

According to Table 8.4, the mold forms obtained by each example according to the present invention had no skin on the mold surface;
The mold form had good air permeability without a cell membrane.

As described above, by limiting the polyol, catalyst, and foam stabilizer used in the method for producing skinless mold foam of the present invention, LA without surface skin and skinless mold foam without cell membrane can be obtained. Not only is it highly useful as a material, but by further treating the obtained foam with an alkaline aqueous solution, it becomes completely skin-free and cell-free, allowing it to be used as a filter with low pressure loss and excellent collection effects. , its industrial value is extremely large.

Example 8 Next, a specific method for manufacturing a foam filter using the method of the present invention will be explained below, including the structure of the foam filter and the structure of the mold. 1(a) shows an external perspective view of the foam filter 200, and FIG. A large number of hollow holes 20 are provided so as not to intersect with each other, and one end side is connected to an inlet portion 23.
, with the other end as the outlet section 24.

Adjacent hollow holes 20 are closed at their ends 22,
The hollow holes 20 communicate with each other via partition walls 21 located between them. This partition wall 21 has a three-dimensional network structure as shown in FIG. 2, and its skeleton 21
Air passes through a through hole 212 formed between 1 and 1. Note that the end portion 22 also has a structure as shown in FIG. 2, but its through hole 212 has become extremely small due to the foaming pressure.

(11) Structure of the mold Figure 3 shows the container part of the mold used in manufacturing the above foam filter, with Figure 8 (a) being a plan view and Figure 3 (b) being a sectional view. It is. The mold container part 1 consists of an end face 5 and a side wall 2, in which columnar members 3 having a square cross section smaller than the area of the compartment are fixed vertically in every other compartment divided into a base shape, and the other end face is open. ing.

On the other hand, FIG. 4 shows a mold lid part combined with the mold container part 1, and FIG.
Figure fb) is a cross-sectional view. The mold lid part 10 is composed of a flat plate lid 15 to which a columnar member 13 is vertically fixed, similar to the mold container part 1 described above. The columnar members 18 are attached to grid-like sections of the mold container section 1 where the columnar members 13 are not attached. In addition, communication holes 16 are provided in each section of the flat plate of the mold lid 10, and communication holes 17 are provided in the side periphery of the flat plate.

A mold is created by combining the mold container portion 1 and the mold lid portion 10 having such a configuration. FIG. 5 shows a cross section of the assembled mold.

A cavity 18 having the same shape as the foam filter to be manufactured is formed inside this mold. The mold lid part 10 and the mold container part 1 are removably fixed with screws 19 through a communication hole 17 provided on the side periphery of the mold lid part 10 so that a predetermined combination can be made.

(iii) Method for manufacturing a foam filter Now, a specific method for manufacturing a foam filter using the mold having the above configuration will be described.

That is, the polyether polyol (
B) 2.59 g of water, 1.5 g of N-ethyno l'morpholine O, l-lyethylenediamine (D
ABCO) 0.109, foam stabilizer B-5246 (manufactured by Goldschmidt ■:] 0.5!j.

Ison Ane h25J? and mix at a speed of 1000 rpm for 8 seconds. This mixture is r
- Wax-based mold release agent (for example, Bond Wax U)
RT-85T) is injected from every other communicating hole 16 of the mold (mold m50'c) shown in FIG. At this time, the air inside the mold is discharged from the remaining communication holes 16 to facilitate the injection of the raw material liquid.

Next, foaming is performed in the cavity 18, and the temperature is 15°C at 80°C.
Heated and cured for ~60 minutes. Thereafter, the mold container part 1 and the mold lid part 10 are removed to obtain a foam molded body.

By the way, in the foam molded article obtained as described above, the foam stabilizer in the raw material liquid, the wax-based mold release agent on the mold surface, and the pressure during foaming combine to cause the mold container part 1 to
The portions of the columnar member 8 and the columnar member 13 of the mold lid 10 are made film-free, so that the columnar members 3, 13
The skin (membrane) is no longer stretched between the 8-dimensional network structure skeletons in contact with the 8-dimensional mesh structure, and the membrane becomes breathable.

Note that, like the foam filter shown in FIG. 1, the partition wall 2
When the thickness of 1 is 2011 or less (1 to 201111), the cells of the form collapse in the gap (mold space; see FIG. 5) between the columnar portion 3 and the columnar portion 18 of the mold. The surface tension of the wax-based mold release agent applied to the inner surface of the mold prevents it from collapsing, which greatly contributes to the molding of skinless foam. Furthermore, the mold shown in FIG. 5 has a structure with good sealing properties that makes it easy to increase the expansion ratio, and this point also contributes to the molding of skinless foam.

Now, the foam molded article produced as described above may be further heated, for example, with an aqueous solution of about 30 g of caustic soda at 80°C to 120°C, if necessary.
℃ for about 5 to 80 hours, and the cell membrane was removed. In this way, a hollow hole with a cylindrical shape with an outer diameter of 1201IS and a length of 150m1 and a square with a side of 5 mm (reference numeral 2 in Fig. 1) was formed.
A foam filter having a partition wall (reference numeral 21 in FIG. 1) with a thickness of 81 m and a vent hole size of 10 to 80 mesh was obtained.

Comparative Test Example 1 Here, an experimental example will be described to demonstrate the superiority of the present invention. All test products had the structure shown in Figure 1 (b), diameter 127 ill, length 110 mm, and partition wall thickness Bin.

The size of the ventilation holes is 60 to 70 meshes, and the size of the hollow holes is 4 squares. and) One of the test products was prepared by the method of Example 8 (lit) described above, and the other test products were prepared using the foam stabilizer described above.

This is a conventional example produced without using a mold release agent.

In addition, all of the above test products were heated at a temperature of 80"0 to 80" after molding.
Approximately 16
The skin (which is formed on each skeleton by time soaking)
After removing thin 1 [[) and washing thoroughly with water, heat 2 at 80”
Dry for 4 hours.

The pressure loss situation when air is flowed through each of the above test items is shown in the 6th section.
As can be understood from FIG. 6, the product obtained by the method of the present invention has a significantly lower pressure loss and a remarkable skin removal effect than the conventional method.

In addition, in the above-mentioned method for manufacturing a foam filter, the mold release agent used was "R-35'R (trade name)" (manufactured by Pond Wax Co., Ltd.). It may be a wax-based material that changes to

Usage Example 1 Using the urethane foam prepared by the method of Example 8 (Ill), activated carbon (granules 1 powder)
Or, an aqueous solution of polyvinyl alcohol (PVA) or polyvinyl petiler/I/(PVB) (PVA or PVB 6 to 100 parts of zeolite)
(10 parts dissolved in 100 parts of warm water at 80 to 90°C) 70 to 90 parts are added and immersed in the well-stirred slurry to fully adhere activated carbon or zeolite to the surface of the urethane foam.

Thereafter, this is centrifuged to scatter excess slurry on the urethane surface. Then dry it in a microwave to remove moisture. In this way, activated carbon or zeolite is deposited on the urethane foam. The material prepared in this way can be used as a fill material for adsorbing and removing bad odors for automobiles.

Usage Example 2 The urethane foam prepared by the method of Example 8 (Ill1) was used to form Cu-Ni-based Fe-Ni-Or-based materials having catalytic performance, Pd, Pt, BJl,
PVA or PvB solution (PvA or
6 to 10 parts of vB (dissolved in 100 parts of 80 to 90°C warm water) and 10 to 20 parts of Cu-Ni system, Fe
-Ni-0r system, Pd, Pt, Rh, Uu
-0.005-1μ ultrafine powder of Ni-Mn metal 30
The foam is immersed in a slurry prepared by adding a portion of the urethane foam and stirring, and then the excess slurry is scattered by a centrifugal separation method to uniformly adhere the slurry containing the metal powder to the surface of the urethane foam. Then in the dryer 80-100
After drying at °C for about 6 hours, it is fired and sintered at a temperature of 700-1000'Q for about 2-4 hours. In this way, a metal carrier having the same shape as the urethane foam can be created. This is a fuel reforming catalyst that can be used as a catalyst when producing methanol, ethanol, etc. by reacting carbon monoxide (or carbon dioxide) with hydrogen.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing a foam filter obtained according to the present invention, FIG. 1(b) is a sectional view showing a cross section of the filter in FIG. 1(al), and FIG. FIGS. 8(a) and 8(b) are a plan view and a sectional view showing an example of a mold container portion used for explaining the present invention, and FIGS. b) is a plan view and a cross-sectional view showing an example of a mold lid part provided for explanation of the present invention; FIG. 5 is a cross-sectional view showing a state in which FIG. 8 and FIG. 4 are combined;
The figure is a characteristic diagram for explaining the present invention in detail. Figure 1 (a) Figure 2 Figure 3 (&) Figure 4 (&)

Claims (1)

[Claims] 1. A method for producing polyurethane foam by mold-foaming an organic polyisocyanate and a polyol in the presence of a foam stabilizer, a catalyst, and a blowing agent, comprising: (1) at least a portion of the polyol containing ethylenic foam; Polymer polyols from unsaturated monomers and polyether polyols and/or polyester polyols (A
), or (A) and polyether polyol (B)
(2) As a catalyst, per 100 parts of polyol, 0.02
~0.2 parts of tertiary amine to accelerate the resinization reaction and 0
．． Using 2 to 0.9 parts of tertiary amine that promotes the foaming reaction, (3) As a foam stabilizer, there are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ (1) [In the formula, A is the average molecular weight of 100 ~700 polyoxyethylene and/or oxypropylene chain, x represents 3 to 20, y represents 3 to 30, R represents H and/or an alkyl group having 1 to 5 carbon atoms and/or an acyl group . (However, the dimethylsiloxane units and polyoxyalkylene siloxane units may be randomly arranged.)] using a silicone foam stabilizer shown in (4) free foaming density of 0.02 to 0.04 g/cm. ^2
A method for producing skinless polyurethane foam, which comprises injecting into a mold an amount of foam stock solution giving a packing ratio of 120 to 300%. 2. The process according to claim 1, wherein (B) contains at least 5% of terminal oxyethylene groups. 3. The manufacturing method according to claim 1 or 2, wherein (B) has an OH value of 10 to 70. 4. The ratio of (A) and (B) is 70:30 to 20:80
The manufacturing method according to any one of claims 1 to 3. 5. The amount of the foam stabilizer is 0 per 100 parts by weight of the polyol.
．． The manufacturing method according to any one of claims 1 to 4, wherein the amount is 5 to 1.5 parts by weight. 6. The tertiary amine catalyst that promotes the resinization reaction is triethylenediamine, tetramethylethylenediamine, tetramethylhexylenediamine, 1,8-diaza-bicyclo[
5,4,0] undecene-7 and/or an organic acid salt thereof. 7. The manufacturing method according to any one of claims 1 to 6, wherein the tertiary amine catalyst that promotes the foaming reaction is N-methylmorpholine, N-ethylmorpholine and/or triethylamine.