CN116162425A - Adhesive and composite product thereof - Google Patents

Abstract

The invention belongs to the technical field of adhesives, and particularly relates to an adhesive and a composite product thereof. The chemical components of the adhesive are aqueous dispersion of blocked aliphatic isocyanate and copolymer emulsion containing styrene and butadiene. The adhesive obtained by the aqueous dispersion of the blocked aliphatic isocyanate and the copolymer emulsion containing styrene and butadiene has simple components, good storage stability and adhesive force, and can be used for bonding difficult-to-bond substrates.

Description

A kind of adhesive and composite product thereof

technical field

The invention belongs to the technical field of adhesives, in particular to an adhesive and its composite product.

Background technique

By combining different materials into different products, products with combined advantages can be obtained. Different materials have different characteristics, such as polyurethane has good wear resistance and can be easily adjusted hardness, polyester film has good mechanical strength and barrier properties, polyethylene film or sheet has good chemical corrosion resistance and Weather resistant, the rubber is very flexible and mechanically strong.

For example, pharmaceutical packaging and food packaging are made of different materials. Many instrument panels and decorative panels for the driver's and co-pilot's seats are composited with polypropylene-based thermoplastic elastomer (TPO) and polyester fabric-based synthetic leather. Patent application US20220072830A1 discloses that a composite with polyethylene film and rubber is used as a waterproof barrier layer for construction. Patent CN102501460B discloses a compound, which contains polymer film such as polyester film and rubber or thermoplastic elastomer. Patent CN208886167U discloses a rubber hose, and the inner wall of the hose has an ultra-high molecular weight polyethylene film attached to the inner rubber.

Different materials perform different functions. However, it is generally not easy to bond between different materials, especially for materials with strong surface inertia such as polyolefins and polyesters. Traditional adhesives are organic solvent-based adhesives. But organic solvents are often detrimental to environmental health, and many are flammable and explosive. Patent application US20220064504A1 discloses a chlorine-containing water-based adhesive to bond leather polyester base cloth and TPO. Although the adhesion can be improved, the formula contains chlorine, which will produce carcinogens when waste is incinerated.

Patent CN105051284B discloses a formula, including acrylic polymer resin containing carboxylic acid groups, epoxy resin, blocked polyisocyanate, styrene-butadiene latex, styrene-butadiene-vinylpyridine latex, Can give polyester and rubber better adhesion. However, the formulation has many components, and the epoxy compound, carboxyl group and isocyanate can react in water, resulting in unstable storage of the formulation, which must be prepared and used immediately.

CN106460313B discloses a formula comprising acrylic resin, epoxy resin, polyisocyanate, styrene-butadiene-vinylpyridine latex and ammonia water. There are still stability problems in this formula, and ammonia water is needed to adjust the pH value, and the use of ammonia water is harmful to the environment and the health of users.

CN105008449B discloses a formula containing polyetheramine, glycidyl ether, and styrene-butadiene-vinylpyridine. Among them, glycidyl ether and amine react rapidly and are therefore unstable.

CN102414362B discloses an adhesive formulation containing glycidyl ether and styrene-butadiene-vinylpyridine and one of piperazine or blocked isocyanate. Epoxy and piperazine can react quickly in water, and the presence of epoxy can also induce the unblocking of blocked isocyanate and affect the stability of the system.

CN106084362B discloses an adhesive composition containing blocked aliphatic isocyanate, epoxy compound, styrene-butadiene copolymer latex and styrene-butadiene-vinylpyridine copolymer latex. Due to the presence of epoxy, it will induce the unblocking of blocked isocyanate and affect the stability of the system.

CN109097993A discloses an adhesive composition containing blocked isocyanate, self-crosslinking acrylic resin, and styrene-butadiene-vinylpyridine latex. This formulation requires a self-crosslinking acrylic resin. The self-crosslinking acrylic resin emulsion contains hydrazine substances, which can induce the unblocking of blocked isocyanate during storage, thus affecting the stability of the system.

CN109082893B discloses an adhesive composition containing dimethylpyrazole-terminated hexamethylene diisocyanate, styrene-butadiene-vinylpyridine and ammonia water. The formulation discloses that the composition is suitable for the secondary treatment of the surface of a material already pretreated with an alkaline aqueous dispersion of caprolactam-blocked isocyanate and epoxy compound, and that the formulation requires environmental and operator health hazards of ammonia.

Therefore, it is necessary to develop an adhesive composition with stable formula and simple composition.

Contents of the invention

The application provides an adhesive and its composite product to solve the technical problem of chlorine element contained in the water-based adhesive.

In a first aspect, the present application provides an adhesive, the chemical composition of which is an aqueous dispersion of blocked aliphatic isocyanate and a copolymer emulsion containing styrene and butadiene.

Optionally, in the copolymer emulsion containing styrene and butadiene, the non-volatile matter accounts for 30%-50% of the mass fraction of the copolymer emulsion containing styrene and butadiene, and styrene accounts for the The mass fraction of the copolymer emulsion containing styrene and butadiene is not higher than 20%. The copolymer containing styrene and butadiene may further contain vinylpyridine monomer not higher than 20% by mass.

Optionally, the aliphatic isocyanate includes a trimer or multimer of hexamethylene diisocyanate, a trimer or multimer of pentamethylene diisocyanate and a trimer of isophorone diisocyanate or polymers.

The raw material of the aqueous dispersion of blocked aliphatic isocyanate also includes any one of butanone oxime, caprolactam and dimethylpyrazole.

Optionally, in the aqueous dispersion of blocked aliphatic isocyanate, the content of isocyanate is ≥3% relative to the total weight of the aqueous dispersion of blocked aliphatic isocyanate.

Optionally, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 2%-90% of blocked aliphatic isocyanate and 10%-98% of a copolymer containing styrene and butadiene of things.

Optionally, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 20%-70% of blocked aliphatic isocyanate and 30%-80% of a copolymer containing styrene and butadiene things.

Optionally, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 30%-60% blocked aliphatic isocyanate and 40%-70% styrene and butadiene-containing copolymer.

In a second aspect, the present application provides a composite product, the composite product includes a first substrate and a second substrate; the adhesive is coated between the first substrate and the second substrate.

Optionally, the first substrate and the second substrate are respectively any one of polyester, polyethylene, polyurethane, rubber, elastomer or polyamide.

Compared with the prior art, the above-mentioned technical solutions provided by the embodiments of the present application have the following advantages:

The adhesive provided in the examples of the present application is an adhesive obtained by an aqueous dispersion of blocked aliphatic isocyanate and a copolymer emulsion containing styrene and butadiene. The composition is simple and has good stability and adhesion , can improve the adhesion between difficult-to-bond substrates.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, In other words, other drawings can also be obtained from these drawings without paying creative labor.

Fig. 1 is a schematic structural diagram of a composite product provided in an embodiment of the present application.

Wherein, 1. the first base material, 2. the second base material, and 3. the adhesive.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present application.

According to a typical embodiment of the present invention, an adhesive is provided, the chemical composition of which is an aqueous dispersion of blocked aliphatic isocyanate and a copolymer emulsion containing styrene and butadiene .

Specifically, the components of the aqueous dispersion of blocked aliphatic isocyanate include blocked aliphatic isocyanate and water.

In some embodiments, in the copolymer emulsion containing styrene and butadiene, the non-volatile matter accounts for 30%-50% of the mass fraction of the styrene-butadiene copolymer emulsion, and styrene accounts for the The mass fraction of the copolymer emulsion containing styrene and butadiene is not higher than 40%. The copolymer containing styrene and butadiene may further contain vinylpyridine monomer not higher than 20% by mass. .

Controlling the mass fraction of vinylpyridine monomer in the copolymer to not more than 20% and controlling the mass fraction of styrene to not more than 40% has the effect of improving adhesion while maintaining flexibility.

In some embodiments, the aliphatic isocyanate includes a trimer or multimer of hexamethylene diisocyanate, a trimer or multimer of pentamethylene diisocyanate, and a trimer or multimer of isophorone diisocyanate. Polymer or Polymer. ; The raw material of the aqueous dispersion of blocked aliphatic isocyanate also includes any one of butanone oxime, caprolactam and dimethylpyrazole as a blocking agent.

Hexamethylene diisocyanate blocked by butanone oxime or dimethylpyrazole or caprolactam can continue to react with hydrophilic groups that can react with isocyanate, such as polyvinyl alcohol, to obtain an aqueous dispersion of aliphatic isocyanate, Has self-emulsifying properties.

In some embodiments, in the aqueous dispersion of blocked aliphatic isocyanate, the content of isocyanate is ≧3% relative to the total weight of the aqueous dispersion of blocked aliphatic isocyanate.

In some embodiments, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 2%-90% blocked aliphatic isocyanate and 10%-98% styrene and butadiene-containing of copolymers.

In some embodiments, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 20%-70% blocked aliphatic isocyanate and 30%-80% styrene and butadiene-containing of copolymers. The copolymer containing styrene and butadiene may further contain a vinylpyridine monomer.

In some embodiments, based on the mass fraction of dry matter, the chemical composition of the adhesive is: 30%-60% aqueous dispersion of blocked aliphatic isocyanate and 40%-70% styrene-containing and butadiene copolymers. The copolymer containing styrene and butadiene may further contain a vinylpyridine monomer.

According to a typical embodiment of the present invention, a composite product is provided. As shown in FIG. 1, the composite product includes a first base material 1 and a second base material 2; the first base material and the second base material The adhesive 3 is coated between the materials.

In some embodiments, the first substrate and the second substrate are respectively any one of polyester, polyethylene, polyurethane, rubber, elastomer or polyamide.

The materials of the first base material and the second base material can be the same or different, and the conventional base material can be any one of polyester, polyethylene, polyurethane, rubber, elastomer or polyamide.

The method of the present invention will be described in detail below in conjunction with examples, comparative examples and experimental data.

Experimental reagents include:

Raw material A: an aqueous dispersion of internally emulsified blocked aliphatic isocyanate, which is a trimer of hexamethylene diisocyanate (HDI), and part of the isocyanate groups on the trimer and hydrophilic groups such as Low molecular weight polyoxyethylene ether reacts to produce self-emulsifying ability in water, and other isocyanate groups react with butanone oxime, emulsified and diluted with water to a non-volatile content of 45%. The isocyanate content in the water dispersion is 4.3% by mass percentage.

Raw material B: an aqueous dispersion of internally emulsified blocked aliphatic isocyanate, which is a trimer of hexamethylene diisocyanate (HDI), and part of the isocyanate groups on the trimer and hydrophilic groups such as Low molecular weight polyoxyethylene ether reacts to produce self-emulsifying ability in water, and other isocyanate groups react with dimethylpyrazole, emulsified and diluted with water to a non-volatile content of 38%. The isocyanate content in the water dispersion is 4.4% by mass percentage.

Ultra-high molecular weight polyethylene film, thickness 0.05mm.

Polyethylene terephthalate (PET) film, 0.05mm.

Unvulcanized rubber consists of the following formula: in parts by mass, natural rubber (1# standard rubber): 90.0 parts; styrene-butadiene rubber (1500 type): 10.0 parts; stearic acid (200 type): 2.0 parts; Accelerator DM: 1.2 parts; Accelerator TT: 0.03 parts; Indirect zinc oxide: 8.0 parts; N330 carbon black: 35.0 parts; Sulfur: 2.5 parts; Binder A: 0.8 parts; Binder RS: 0.96 parts; Total: 150.49 parts; The unvulcanized rubber mixed with this formula was calendered into a sheet about 5mm thick.

Adhesive A and adhesive RS: derived from GB/T 2942-2009 cited in the national standard GB/T19390-2014.

Polyurethane thermoplastic elastomer sheet, thickness 3mm. Among them, polyurethane is an aromatic polyester isocyanate with a hardness of Shore A of 92 degrees.

Styrene-butadiene-vinylpyridine copolymer emulsion, wherein the mass fraction of non-volatile matter is 40%, the mass content of vinylpyridine in the copolymer is 15%, and the mass content of styrene is 15%. Denoted as SBVPy.

Butadiene-styrene copolymer latex with a non-volatile content of 40%. The mass content of styrene in the copolymer is 30%. Expressed as SBR.

soft water.

Comparative examples 1 and 2 and embodiment 1 to 4, and the preparation of comparative example 1-2:

According to the formula in Table 1, prepare 10 grams of the mixture for each composition (including the formula with only one ingredient), stir it at a slow speed for about 3 minutes, pour it into a polytetrafluoroethylene mold with a cavity of 120mmx60mmx2mm, and let it dry naturally After more than 72 hours, an adhesive dry film is obtained.

Cut the dry adhesive film obtained above into a size of 80mmx50mm, and cut the substrate 2 (polyurethane sheet) and substrate 1 (UHMWPE film) into a size of 90mmx60mm, and cut the dry adhesive film Sandwiched between polyurethane and UHMWPE films to form a three-layer sandwich composite, and then hot-pressed at 1 MPa pressure for 60 s on a flat-bed hot press preheated to 130 ^o C.

Cut the hot-pressed sample into a strip sample with a length of 60mm and a width of 25mm, and separate the polyurethane and ultra-high molecular weight polyethylene film at one end of the sample, and perform it on an Instron® 5566 universal material testing machine according to the ASTM D1876-08(2015)e1 standard A 180 degree peel test was performed and an average peel force result was obtained.

Table 1 .

It can be seen from Table 1 that the adhesion effect of the mixture of blocked isocyanate and copolymer containing styrene and butadiene is significantly higher than that of blocking isocyanate alone or only copolymer containing styrene and butadiene alone formula.

Examples 5 to 8 and comparative examples 3 and 4; according to table 2, each composition of the formula is prepared with 300 grams, and then the PET film with a size of 90mmx60mm is immersed in the composition and taken out, and the excess liquid is squeezed out. Then dry it in an oven at 230 degrees for 1 minute. Lay the dried film with a rubber sheet with a size of 90mmx600mm, and put a piece of release paper between the film and the rubber sheet at one end of the lamination to facilitate separation after molding. Then take out the lamination by hot pressing under 5 MPa pressure for 30 minutes on a flat hot press preheated to 140 degrees, and then place it at room temperature for more than 12 hours.

Cut the above sample into a strip sample with a width of 25mm and a length of 60mm, separate the end with the release paper, perform a 180-degree peel test on an Instron®5566 universal testing machine according to the ASTM D1876-08(2015)e1 standard, and obtain the average peel force result.

Table 2.

It can be seen from Table 2 that the adhesion effect of the mixture of blocked isocyanate and copolymer containing styrene and butadiene is significantly higher than that of the formulation with blocked isocyanate or copolymer containing styrene and butadiene alone .

The composition complexity and stability comparison with the published formulations are shown in Table 3.

table 3.

It can be seen that the adhesive of the present application has simple components, thus low cost, and at the same time, has good stability and strong cohesive force.

It should be noted that in this article, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these No such actual relationship or order exists between entities or operations. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above descriptions are only specific embodiments of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Accordingly, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims (11)

1. An adhesive, characterized in that, the chemical component of the adhesive is an aqueous dispersion of blocked aliphatic isocyanate and an emulsion containing a copolymer of styrene and butadiene. 2. The adhesive according to claim 1, wherein the aliphatic isocyanate comprises trimer or multimer of hexamethylene diisocyanate, trimer or multimer of pentamethylene diisocyanate polymer and trimer or polymer of isophorone diisocyanate. 3. adhesive according to claim 1, is characterized in that, in the emulsion containing the copolymer of styrene and butadiene, non-volatile matter accounts for the quality of described styrene-butadiene copolymer emulsion The fraction is 30%-50%, and the mass fraction of styrene in the styrene-butadiene copolymer emulsion is no higher than 20%. 4. The adhesive according to claim 1, wherein the copolymer of styrene and butadiene further contains vinylpyridine monomer, and the content of vinylpyridine monomer is not higher than 20%. 5. The adhesive according to claim 1, wherein the raw material of the blocked aliphatic isocyanate comprises a trimer of hexamethylene diisocyanate; the aqueous dispersion of the blocked aliphatic isocyanate The raw material also includes any one of butanone oxime, caprolactam and dimethylpyrazole. 6. The adhesive according to claim 1, wherein, in the aqueous dispersion of the blocked aliphatic isocyanate, the isocyanate content is relative to the total weight of the aqueous dispersion of the blocked aliphatic isocyanate ≥3%. 7. The adhesive according to claim 1, characterized in that, in terms of mass fraction, the chemical components of the adhesive are: 2%-90% aqueous dispersion of blocked aliphatic isocyanate and 10% %-98% copolymer emulsion containing styrene and butadiene. 8. The adhesive according to claim 1, characterized in that, in terms of mass fraction, the chemical components of the adhesive are: 20%-70% aqueous dispersion of blocked aliphatic isocyanate and 30% %-80% copolymer emulsion containing styrene and butadiene. 9. The adhesive according to claim 1, characterized in that, in terms of mass fraction, the chemical components of the adhesive are: 30%-60% aqueous dispersion of blocked aliphatic isocyanate and 40% %-70% copolymer emulsion containing styrene and butadiene. 10. A composite product, characterized in that, the composite product comprises a first base material and a second base material; between the first base material and the second base material, a chemical component is coated with a closed type aliphatic Adhesives consisting of aqueous dispersions of isocyanates and mixtures containing emulsions of styrene and butadiene copolymers. 11. The composite product according to claim 8, wherein the first substrate and the second substrate are respectively any one of polyester, polyethylene, polyurethane, rubber, elastomer or polyamide.

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