A kind of adhesive without surface modified aramid material and preparation method thereof

Abstract

The invention discloses an adhesive for aramid material without surface modification and a preparation method thereof, and relates to the technical field of aramid material adhesives. The adhesive comprises the following raw materials in parts by weight: 100 parts of phenyl epoxy resin; 19 to 25 parts of silane coupling agent; 0.02 to 0.04 parts of isopropyl tri(dioctyl pyrophosphoryl) titanate (TCA-K38S); and 4 to 8 parts of calcium carbonate. The phenyl epoxy resin is prepared by the following raw materials in parts by weight: 50 to 90 parts of bisphenol A epoxy resin E20; 10 to 50 parts of phenyl silicone resin; 60 parts of xylene; 40 parts of ethyl acetate; and 0.1 to 0.5 parts of tetraisopropyl titanate. The phenyl epoxy resin adhesive for aramid materials prepared by the present invention does not crack, debond, or yellow the aramid / glass fiber adhesive sheet at high temperatures without surface treatment, and has high temperature resistance and excellent bonding ability. Compared with aramid surface-modified adhesives, the operation is simpler and the bonding effect is not affected.

Description

Technical Field

[0001] The invention relates to the technical field of aramid material adhesives, in particular to an adhesive for aramid material without surface modification and a preparation method thereof. Background Art

[0002] The discovery of aramid is considered to be the most important historical process in the materials industry. Aramid fiber has excellent thermal stability, insulation and low density. It also has ultra-high strength, high modulus, high temperature resistance, acid and alkali resistance, light weight and other excellent properties. In order to meet the needs of modern warfare, bulletproof vests in developed countries are made of aramid fiber. In addition to military applications, aramid, as a high-tech fiber material, can be used in aerospace, construction, automobiles and other aspects to improve the national economic level. However, due to the high crystallinity of aramid fiber, the surface of aramid is smooth and the chemical activity is low, resulting in poor adhesion between aramid fiber and other polymer interfaces, easy to fall off under external force, and unsatisfactory reinforcement effect.

[0003] At present, in order to solve the problem of smooth surface and low chemical activity of aramid fiber, it is proposed to modify the surface of aramid fiber, increase the surface roughness of aramid fiber by chemical modification and physical modification, and enhance the bonding ability of the composite material surface. That is, aramid fiber is pretreated by surface etching, surface grafting, plasma treatment and ultrasonic impregnation, but the chemical modification and physical modification operations are cumbersome.

[0004] Therefore, developing an adhesive that can be directly used for aramid fibers without surface modification is a major problem that scientific researchers need to solve. Some literature states that room temperature vulcanized silicone rubber is first coated on both sides of the composite surface, and then methylphenyl silicone resin is coated to improve the bonding performance. Silicone resin has a highly cross-linked structure, and the introduction of phenyl groups in the side chain can improve thermal elasticity and adhesion. However, the bonding strength of pure polysiloxane adhesives is low, which limits the synthesis and preparation of adhesives. Therefore, we proposed an adhesive for aramid materials without surface modification and a preparation method thereof to solve the problems raised. Summary of the invention

[0005] The purpose of the present invention is to provide an adhesive for aramid material without surface modification and a preparation method thereof, so as to achieve the purpose that the phenyl epoxy resin adhesive for aramid material does not crack, debond or yellow at high temperature without surface treatment, and has high temperature resistance and excellent bonding ability. Compared with the adhesive with aramid surface modification, the operation is simpler and the bonding effect is not affected.

[0006] To achieve the above object, the present invention provides the following technical solution: an adhesive without surface-modified aramid material, comprising the following raw materials in parts by weight: Phenyl epoxy resin - 100 parts; Silane coupling agent - 19 to 25 parts; Isopropyl tri(dioctylpyrophosphoryl) titanate (TCA-K38S) - 0.02 to 0.04 parts; Calcium carbonate - 4 to 8 parts.

[0007] Preferably, the phenyl epoxy resin is prepared from the following raw materials in parts by weight: Bisphenol A epoxy resin E20-50-90 parts; Phenyl silicone resin - 10 to 50 parts; Xylene - 60 parts; Ethyl acetate - 40 parts; Tetraisopropyl titanate - 0.1 to 0.5 parts.

[0008] Preferably, the phenyl silicone resin is prepared from the following raw materials in parts by weight: Phenylmethyldimethoxysilane - 100 parts; Hydrochloric acid - 0.004 parts; Water - 0.05 parts; Calcium carbonate - 0.016 parts.

[0009] Preferably, the silane coupling agent is one of 3-aminopropyltrimethoxy, 3-aminopropyltriethoxysilane, anilinemethyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, and N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane.

[0010] Preferably, the amount of the silane coupling agent is calculated as W=(M / Hn)*E, where M is the molecular weight of the amine curing agent, Hn is the number of active hydrogen atoms on the amine group in the curing agent, and E is the epoxy value of the epoxy resin.

[0011] The present invention also provides a method for preparing an adhesive without surface-modified aramid material, comprising: S1, adding 100 parts of phenylmethyldimethoxysilane into a three-necked flask and heating it to 70°C, adding 0.004 parts of hydrochloric acid into the three-necked flask, stirring for 30 minutes, adding 0.05 parts of water dropwise at a speed of 40 rpm using a peristaltic pump, then stirring for 2 hours under nitrogen, adding 0.016 parts of calcium carbonate to neutralize the reaction and filtering to obtain an intermediate product, phenyl silicone resin; S2, after adding 60 parts of xylene and 40 parts of ethyl acetate into a three-necked flask and stirring evenly, add 50-90 parts of bisphenol A epoxy resin E20 and 10-50 parts of phenyl silicone resin into the three-necked flask and stir until completely dissolved, heat to 70°C, add 0.1-0.5 parts of tetraisopropyl titanate as a catalyst, pass nitrogen and stir for 2 hours, distill at 130°C to remove methanol until no liquid drops out, vacuum and stir for 10-25 minutes to remove the solvent until no liquid drops out, and cool to room temperature to obtain phenyl epoxy resin; S3. Mix 19 to 25 parts of silane coupling agent, 4 to 8 parts of calcium carbonate and 0.02 to 0.04 parts of isopropyl tri(dioctyl pyrophosphoryl) titanate (TCA-K38S) to prepare a coupling agent, then pour the prepared coupling agent and 100 parts of phenyl epoxy resin into a straight bottle, stir evenly with a vacuum degassing mixer to remove bubbles, and obtain a phenyl epoxy resin adhesive.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The phenyl epoxy resin adhesive for aramid materials prepared by the present invention does not crack, debond, or yellow the aramid / glass fiber adhesive sheet at high temperatures without surface treatment, and has high temperature resistance and excellent bonding ability. Compared with aramid surface-modified adhesives, the operation is simpler and the bonding effect is not affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the process of the preparation method of the present invention; Figure 2 This is a physical diagram of the solution of the present invention; Figure 3 This is a physical picture of the prior art. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0015] See also Figure 1 The present invention provides a technical solution: an adhesive without surface-modified aramid material, comprising the following raw materials in parts by weight: Phenyl epoxy resin - 100 parts; Silane coupling agent - 19 to 25 parts; Isopropyl tri(dioctylpyrophosphoryl) titanate (TCA-K38S) - 0.02 to 0.04 parts; Calcium carbonate - 4 to 8 parts.

[0016] The phenyl epoxy resin is prepared from the following raw materials in parts by weight: Bisphenol A epoxy resin E20-50-90 parts; Phenyl silicone resin - 10 to 50 parts; Xylene - 60 parts; Ethyl acetate - 40 parts; Tetraisopropyl titanate - 0.1 to 0.5 parts.

[0017] The phenyl silicone resin is prepared from the following raw materials in parts by weight: Phenylmethyldimethoxysilane - 100 parts; Hydrochloric acid - 0.004 parts; Water - 0.05 parts; Calcium carbonate - 0.016 parts.

[0018] See also Figure 1 The silane coupling agent is one of 3-aminopropyltrimethoxy, 3-aminopropyltriethoxysilane, anilinemethyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, and N-β-(aminoethyl)-γaminopropyltrimethoxysilane. The amount of the silane coupling agent is calculated as W=(M / Hn)*E, where M is the molecular weight of the amine curing agent, Hn is the number of active hydrogen atoms on the amine group in the curing agent, and E is the epoxy value of the epoxy resin.

[0019] The present invention also provides a method for preparing an adhesive without surface-modified aramid material, comprising: S1, adding 100 parts of phenylmethyldimethoxysilane into a three-necked flask and heating it to 70°C, adding 0.004 parts of hydrochloric acid into the three-necked flask, stirring for 30 minutes, adding 0.05 parts of water dropwise at a speed of 40 rpm using a peristaltic pump, then stirring for 2 hours under nitrogen, adding 0.016 parts of calcium carbonate to neutralize the reaction and filtering to obtain an intermediate product, phenyl silicone resin; S2, after adding 60 parts of xylene and 40 parts of ethyl acetate into a three-necked flask and stirring evenly, add 50-90 parts of bisphenol A epoxy resin E20 and 10-50 parts of phenyl silicone resin into the three-necked flask and stir until completely dissolved, heat to 70°C, add 0.1-0.5 parts of tetraisopropyl titanate as a catalyst, pass nitrogen and stir for 2 hours, distill at 130°C to remove methanol until no liquid drops out, vacuum and stir for 10-25 minutes to remove the solvent until no liquid drops out, and cool to room temperature to obtain phenyl epoxy resin; S3, 19 to 25 parts of silane coupling agent, 4 to 8 parts of calcium carbonate and 0.02 to 0.04 parts of isopropyl tri(dioctyl pyrophosphoryl) titanate (TCA-K38S) are mixed evenly to prepare a coupling agent, and then the prepared coupling agent and 100 parts of phenyl epoxy resin are poured into a straight bottle, and after being stirred evenly with a vacuum degassing mixer to remove bubbles, a phenyl epoxy resin adhesive is obtained; Calcium carbonate has a highly ordered atomic arrangement structure and can be used to enhance epoxy bonding performance. Isopropyl tri(dioctylpyrophosphoryl) titanate (TCA-K38S) can reduce the interaction between calcium carbonate molecules and improve the dispersibility of calcium carbonate. The coupling agent prepared by combining with silane coupling agent and phenyl epoxy resin can be used for aramid interface without complicated surface pretreatment to obtain high bonding performance epoxy resin adhesive and high viscosity adhesive. The prepared high viscosity adhesive was coated on the interface of aramid and glass fiber, the curing time was 10 min at 240 ° C, the tensile strength was 19 MPa, and the aramid / glass fiber adhesive sheet did not fall off after curing, and the bonding effect was significant. At the same time, the aramid / glass fiber adhesive sheet prepared by phenyl epoxy resin adhesive was subjected to high and low temperature thermal shock test. The treatment conditions were: 50 ° C (30 min) to 240 ° C (70 min), and the cycle was 500 times. The heating or cooling rate was 5 ° C / min each time. The performance of the adhesive sheet was stable, and no yellowing and debonding occurred (such as Figure 2 As shown); In addition, a pure epoxy resin adhesive was coated on the surface of aramid / glass fiber for comparison. When subjected to high and low temperature thermal shock tests, yellowing and bulging occurred in the second cycle (as shown in Figure 3 as shown).

[0020] Therefore, the phenyl epoxy resin adhesive for aramid materials prepared by the present invention, under the premise of no surface treatment, the aramid / glass fiber adhesive sheet does not crack, debond, or yellow at high temperatures, has high temperature resistance and excellent bonding ability, is simpler to operate than aramid surface-modified adhesives, and the bonding effect is not affected.

[0021] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An adhesive without surface-modified aramid material, characterized in that: The method is prepared from the following raw materials in parts by weight: Phenyl epoxy resin - 100 parts; Silane coupling agent - 19 to 25 parts; Isopropyl tri(dioctylpyrophosphoryl) titanate (TCA-K38S) - 0.02 to 0.04 parts; Calcium carbonate - 4 to 8 parts.

2. The adhesive of non-surface-modified aramid material according to claim 1, characterized in that: The phenyl epoxy resin is prepared from the following raw materials in parts by weight: Bisphenol A epoxy resin E20-50-90 parts; Phenyl silicone resin - 10 to 50 parts; Xylene - 60 parts; Ethyl acetate - 40 parts; Tetraisopropyl titanate - 0.1 to 0.5 parts.

3. The adhesive of the non-surface-modified aramid material according to claim 2, characterized in that: The phenyl silicone resin is prepared from the following raw materials in parts by weight: Phenylmethyldimethoxysilane - 100 parts; Hydrochloric acid - 0.004 parts; Water - 0.05 parts; Calcium carbonate - 0.016 parts.

4. The adhesive of claim 1, wherein: The silane coupling agent is one of 3-aminopropyltrimethoxy, 3-aminopropyltriethoxysilane, anilinemethyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and N-β-(aminoethyl)-γaminopropyltrimethoxysilane.

5. The adhesive of non-surface-modified aramid material according to claim 1, characterized in that: The calculation method for the amount of the silane coupling agent is W=(M / Hn)*E, where M is the molecular weight of the amine curing agent, Hn is the number of active hydrogen atoms on the amine group in the curing agent, and E is the epoxy value of the epoxy resin.

6. The method for preparing an adhesive without surface-modified aramid material according to claims 1-5, characterized in that: include: S1, adding 100 parts of phenylmethyldimethoxysilane into a three-necked flask and heating it to 70°C, adding 0.004 parts of hydrochloric acid into the three-necked flask, stirring for 30 minutes, adding 0.05 parts of water dropwise at a speed of 40 rpm using a peristaltic pump, then stirring for 2 hours under nitrogen, adding 0.016 parts of calcium carbonate to neutralize the reaction and filtering to obtain an intermediate product, phenyl silicone resin; S2, after adding 60 parts of xylene and 40 parts of ethyl acetate into a three-necked flask and stirring evenly, add 50-90 parts of bisphenol A epoxy resin E20 and 10-50 parts of phenyl silicone resin into the three-necked flask and stir until completely dissolved, heat to 70°C, add 0.1-0.5 parts of tetraisopropyl titanate as a catalyst, pass nitrogen and stir for 2 hours, distill at 130°C to remove methanol until no liquid drops out, vacuum and stir for 10-25 minutes to remove the solvent until no liquid drops out, and cool to room temperature to obtain phenyl epoxy resin; S3. Mix 19 to 25 parts of silane coupling agent, 4 to 8 parts of calcium carbonate and 0.02 to 0.04 parts of isopropyl tri(dioctyl pyrophosphoryl) titanate (TCA-K38S) to prepare a coupling agent, then pour the prepared coupling agent and 100 parts of phenyl epoxy resin into a straight bottle, stir evenly with a vacuum degassing mixer to remove bubbles, and obtain a phenyl epoxy resin adhesive.

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