Process for preparing a high-strength silicone-nylon composite

Abstract

The application relates to the technical field of silica gel, and discloses a preparation process of a silica gel-nylon composite material with high bonding strength, which comprises vinyl polydimethylsiloxane, glycidyl ether-based organosilicon polyamide, hydrogen-containing silicone oil, tackifier and alkyne alcohol inhibitor. The glycidyl ether-based organosilicon polyamide contains an epoxy group, can react with terminal amino groups in nylon polyamide molecular chains in a nylon fiber membrane, simultaneously contains an amide group, can interact with amide bonds in the nylon polyamide molecular chains through hydrogen bonds, significantly improves the bonding force and bonding strength between the silica gel adhesive and the nylon fiber membrane, and exhibits higher peel resistance and bonding performance. The glycidyl ether-based organosilicon polyamide has both rigid polyaramid structures and flexible siloxane structures, is beneficial to improving the tensile performance and tear strength of the adhesive, and exhibits higher mechanical performance.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of silica gel, in particular to a preparation process of a silica gel-nylon composite material with high bonding strength. BACKGROUND

[0002] Nylon fibers have high mechanical strength, good wear resistance and strong water resistance, and are widely used in sound box cover cloth, wheel conveyor belt lining cloth and parachutes. When nylon fibers are bonded with plastic, metal and other materials to form a composite material, a bonding agent such as a polyurethane type or a silica gel type bonding agent needs to be added. The silica gel type bonding agent has good weather resistance, water resistance and corrosion resistance and is a bonding agent with excellent performance. However, the bonding force between the silica gel type bonding agent and nylon is low, the bonding performance is poor, and the mechanical strength of the silica gel type bonding agent is low, which hinders the practical application of the silica gel type bonding agent in nylon and other materials. The patent with the publication number CN115926733A discloses a condensation type rapid heat curing silicone rubber adhesive, which is prepared by using condensation type liquid silicone rubber and GDS curing agent as main raw materials. The obtained silicone rubber adhesive has high bonding strength and good bonding force for nylon, polyester and most plastics. However, the silicone rubber adhesive does not have good tensile properties, tear strength and other mechanical properties.

[0003] Inventive content silicone rubber adhesive

[0004] The application solves the problems of poor mechanical properties of the silica gel bonding agent and low bonding performance between the silica gel bonding agent and nylon materials.

[0005] The application provides a preparation process of a silica gel-nylon composite material with high bonding strength.

[0006] (1) 1,3-bis(3-aminopropyl)tetramethyldisiloxane (CAS registration number 2469-55-8), 5-glycidyl ether isophthaloyl chloride and pyridine are added to N,N-dimethylformamide, stirred and reacted, then diluted with ethanol, filtered, washed with ethanol and dried to obtain glycidyl ether-based organosilicon polyamide. The reaction formula is as follows:

[0007]

[0008] (2) Glycidyl ether-based organosilicon polyamide, hydrogen-containing silicone oil, tackifier, alkyne alcohol inhibitor and Karstedt catalyst are added to vinyl polydimethylsiloxane, uniformly mixed, vacuum degassed to obtain a silica gel bonding agent, then the silica gel bonding agent is coated on the surface of a nylon fiber membrane, and vulcanization treatment is performed to obtain a silica gel-nylon composite material with high bonding strength.

[0009] Further, in (1), the ratio of 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 5-glycidyl ether isophthaloyl chloride, pyridine is 1 mol:(0.9-1.1) mol:(0.9-1.1) mol.

[0010] Further, in (1), the reaction temperature is 15-25℃, and the reaction time is 5-8h.

[0011] Further, in (2), the ratio of vinyl polydimethylsiloxane, glycidyl ether-based silicone polyamide, hydrogen-containing silicone oil is 100g:(0.5-6)g:(8-9.2)g.

[0012] Further, in (2), the vulcanization treatment is first treated at 60-70℃ for 30-40min, and then treated at 20-30℃ for 24-36h.

[0013] Further, the preparation method of the 5-glycidyl ether isophthaloyl chloride is:

[0014] S1, add 5-hydroxy isophthalic acid dimethyl ester (CAS registration number 13036-02-7), epichlorohydrin, potassium carbonate in the ratio of 1 mol:(3-3.6) mol:(1.5-2) mol to acetone, and carry out microwave reaction in a microwave reaction kettle, control the microwave power to be 100-150W, the reaction time is 15-30min, and condensation reflux is carried out during the reaction; After filtration, the filtrate is distilled under reduced pressure, washed with water, and then the product is dissolved in 1,4-dioxane, 20-35% sodium hydroxide aqueous solution is added, heated to 90-100℃, and hydrolysis reaction is carried out for 8-15h, condensation reflux is carried out during the reaction, 1,4-dioxane is removed by distillation under reduced pressure, hydrochloric acid is added to adjust the pH to 2-3, and precipitate is precipitated, after filtration, the product is added to ethyl acetate for recrystallization to obtain 5-glycidyl ether isophthalic acid. The reaction formula is as follows:

[0015]

[0016] S2, add 5-glycidyl ether isophthalic acid to thionyl chloride, heat to 60-70℃, react for 3-5h, distill under reduced pressure, and dry to obtain 5-glycidyl ether isophthaloyl chloride. The reaction formula is as follows:

[0017]

[0018] The technical effect of the present application is that: the present application carries out etherification reaction on 5-hydroxy dimethyl isophthalate and epichlorohydrin by microwave irradiation reaction, and then carries out hydrolysis and acyl chloride reaction to obtain 5-glycidyl ether isophthaloyl chloride, and then carries out amidation polymerization reaction with 1,3-bis(3-aminopropyl)tetramethyldisiloxane to obtain a novel glycidyl ether-based organosilicon polyamide, and the glycidyl ether-based organosilicon polyamide is used as an additive modifier of a silica adhesive.

[0019] The glycidyl ether-based organosilicon polyamide of the present application contains an organosilicon structural unit, and has good compatibility with vinyl polydimethylsiloxane and hydrogen-containing silicone oil, so that the glycidyl ether-based organosilicon polyamide is uniformly dispersed in the matrix of the silica adhesive, and the glycidyl ether-based organosilicon polyamide contains an epoxy group and can react with terminal amino groups in the nylon polyamide molecular chain in the nylon fiber membrane, and the glycidyl ether-based organosilicon polyamide contains an amide group and can interact with amide bonds in the nylon polyamide molecular chain by hydrogen bonding, thereby significantly improving the bonding force and adhesive strength between the silica adhesive and the nylon fiber membrane, and exhibiting higher peel resistance and adhesive performance.

[0020] The glycidyl ether-based organosilicon polyamide added in the present application has both rigid polyaramid structure and flexible siloxane structure, and has good compatibility with vinyl polydimethylsiloxane and hydrogen-containing silicone oil components in the silica adhesive, and when added into the silica adhesive, the tensile performance and tear strength of the adhesive are significantly improved, and higher mechanical performance is exhibited. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art based on the present application belong to the scope of protection of the present application.

[0022] The vinyl polydimethylsiloxane of the present application is HY-1100. The hydrogen-containing silicone oil is TSF-484. The tackifier is XYS-901.

[0023] Example 1

[0024] S1, 3 mmol of 5-hydroxy isophthalic acid dimethyl ester, 9 mmol of epichlorohydrin, 4.5 mmol of potassium carbonate were added into 12 mL of acetone, the solution was subjected to microwave reaction in a microwave reactor for 15 min, the microwave power was controlled at 150 W, and condensation reflux was performed during the reaction; after filtration, the filtrate was distilled under reduced pressure, washed with water, and then the product was dissolved in 8 mL of 1,4-dioxane, 4 mL of 20% sodium hydroxide aqueous solution was added, heated to 90°C, and hydrolysis reaction was performed for 15 h, condensation reflux was performed during the reaction, 1,4-dioxane was removed by distillation under reduced pressure, hydrochloric acid was added to adjust the pH to 3, precipitate was separated out, after filtration, the product was recrystallized in ethyl acetate to obtain 5-glycidyl ether isophthalic acid.

[0025] S2, 3 mmol of 5-glycidyl ether isophthalic acid was added into 40 mmol of sulfurous chloride, heated to 60°C, reacted for 5 h, distilled under reduced pressure, and dried to obtain 5-glycidyl ether isophthaloyl chloride.

[0026] Example 2

[0027] S1, 3 mmol of 5-hydroxy isophthalic acid dimethyl ester, 10.8 mmol of epichlorohydrin, 6 mmol of potassium carbonate were added into 12 mL of acetone, the solution was subjected to microwave reaction in a microwave reactor for 30 min, the microwave power was controlled at 100 W, and condensation reflux was performed during the reaction; after filtration, the filtrate was distilled under reduced pressure, washed with water, and then the product was dissolved in 6 mL of 1,4-dioxane, 3 mL of 35% sodium hydroxide aqueous solution was added, heated to 100°C, and hydrolysis reaction was performed for 8 h, condensation reflux was performed during the reaction, 1,4-dioxane was removed by distillation under reduced pressure, hydrochloric acid was added to adjust the pH to 2, precipitate was separated out, after filtration, the product was recrystallized in ethyl acetate to obtain 5-glycidyl ether isophthalic acid.

[0028] S2, 3 mmol of 5-glycidyl ether isophthalic acid was added into 60 mmol of sulfurous chloride, heated to 70°C, reacted for 3 h, distilled under reduced pressure, and dried to obtain 5-glycidyl ether isophthaloyl chloride.

[0029] Example 3

[0030] (1) 10 mmol of 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 11 mmol of 5-glycidyl ether isophthaloyl chloride (the same as the preparation process of Example 1), and 11 mmol of pyridine were added into 50 mL of N,N-dimethylformamide, and stirred at 15°C for 8 h, diluted with ethanol, filtered, washed with ethanol, and dried to obtain glycidyl ether organosilicon polyamide.

[0031] (2) To 100 g of vinyl polydimethylsiloxane, 0.5 g of glycidyl ether-based silicone polyamide, 8.5 g of hydrogen-containing silicone oil, 4 g of tackifier, 0.4 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.22 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber membrane, sulfurized at 60°C for 30 min, and then sulfurized at 25°C for 24 h to obtain a silicone-nylon composite material with high bonding strength.

[0032] Example 4

[0033] (1) To 30 mL of N,N-dimethylformamide, 10 mmol of 1,3-bis(3- aminopropyl)tetramethyldisiloxane, 9 mmol of 5-glycidyl ether isophthaloyl chloride (the same as the preparation process of Example 1), and 9 mmol of pyridine were added, stirred at 25°C for 5 h, diluted with ethanol, filtered, washed with ethanol, and dried to obtain a glycidyl ether-based silicone polyamide.

[0034] (2) To 100 g of vinyl polydimethylsiloxane, 2 g of glycidyl ether-based silicone polyamide, 8 g of hydrogen-containing silicone oil, 8 g of tackifier, 0.6 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.15 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber membrane, sulfurized at 65°C for 40 min, and then sulfurized at 20°C for 36 h to obtain a silicone-nylon composite material with high bonding strength.

[0035] Example 5

[0036] (1) To 30 mL of N,N-dimethylformamide, 10 mmol of 1,3-bis(3- aminopropyl)tetramethyldisiloxane, 9 mmol of 5-glycidyl ether isophthaloyl chloride (the same as the preparation process of Example 1), and 9 mmol of pyridine were added, stirred at 20°C for 6 h, diluted with ethanol, filtered, washed with ethanol, and dried to obtain a glycidyl ether-based silicone polyamide.

[0037] (2) To 100 g of vinyl polydimethylsiloxane, 4 g of glycidyl ether-based silicone polyamide, 9.2 g of hydrogen-containing silicone oil, 3 g of tackifier, 0.6 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.3 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber membrane, sulfurized at 60°C for 40 min, and then sulfurized at 30°C for 24 h to obtain a silicone-nylon composite material with high bonding strength.

[0038] Example 6

[0039] (1) To 40 mL of N,N-dimethylformamide, 10 mmol of 1,3-bis(3- aminopropyl)tetramethyldisiloxane, 10 mmol of 5-glycidyl ether isophthaloyl chloride (same as the preparation process of Example 1), 10 mmol of pyridine were added, and the reaction was stirred at 25°C for 5 h, diluted with ethanol, filtered, washed with ethanol, and dried to obtain a glycidyl ether-based silicone polyamide.

[0040] (2) To 100 g of vinyl polydimethylsiloxane, 6 g of glycidyl ether-based silicone polyamide, 8 g of hydrogen-containing silicone oil, 5 g of tackifier, 0.5 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.15 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber film, vulcanized at 70°C for 30 min, and then vulcanized at 20°C for 36 h to obtain a silicone-nylon composite material having high bonding strength.

[0041] Comparative Example 1

[0042] (1) To 100 g of vinyl polydimethylsiloxane, 8.5 g of hydrogen-containing silicone oil, 4 g of tackifier, 0.4 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.22 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber film, vulcanized at 60°C for 30 min, and then vulcanized at 25°C for 24 h to obtain a silicone-nylon composite material having high bonding strength.

[0043] Comparative Example 2

[0044] (1) To 50 mL of N,N-dimethylformamide, 10 mmol of 1,3-bis(3- aminopropyl)tetramethyldisiloxane, 11 mmol of isophthaloyl chloride 11 mmol of pyridine were added, and the reaction was stirred at 15°C for 8 h, diluted with ethanol, filtered, and washed with ethanol to obtain a silicone polyamide.

[0045] (2) To 100 g of vinyl polydimethylsiloxane, 0.5 g of silicone polyamide, 8.5 g of hydrogen-containing silicone oil, 4 g of tackifier, 0.4 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, and 0.22 g of Karstedt catalyst were added, mixed, and vacuum degassed to obtain a silicone adhesive, which was then coated on the surface of a nylon fiber film, vulcanized at 60°C for 30 min, and then vulcanized at 25°C for 24 h to obtain a silicone-nylon composite material having high bonding strength.

[0046] Comparative Example 3

[0047] (1) To 50 mL of N,N-dimethylformamide, add 10 mmol of ethylenediamine, 11 mmol of 5-glycidyl ether isophthaloyl chloride (same as the preparation process of Example 1), 11 mmol of pyridine, stir at 15°C for 8h, dilute with ethanol, filter, wash with ethanol and dry to obtain glycidyl ether polyamide.

[0048] (2) To 100 g of vinyl polydimethylsiloxane, add 0.5 g of glycidyl ether polyamide, 8.5 g of hydrogen-containing silicone oil, 4 g of tackifier, 0.4 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, 0.22 g of Karstedt catalyst, mix well, vacuum degassing to obtain a silicone adhesive, then coat it on the surface of a nylon fiber film, first sulfurize at 60°C for 30 min, then sulfurize at 25°C for 24 h to obtain a silicone-nylon composite material with high bonding strength.

[0049] According to GB / T 2792-1998 method, test the 180° peel strength between the silicone and the nylon material. The temperature is 25°C.

[0050] Table 1 Peel strength test of silicone adhesive

[0051] 180° peel strength (N / 25mm) Example 3 10.2 Example 4 11.6 Example 5 9.7 Example 6 10.9 Comparative Example 1 6.4 Comparative Example 2 7.5 Comparative Example 3 9.5

[0052] The mechanical properties of the silicone adhesive are tested as follows: taking Example 3 as an example, to 100 g of vinyl polydimethylsiloxane, add 0.5 g of glycidyl ether-based silicone polyamide, 8.5 g of hydrogen-containing silicone oil, 4 g of tackifier, 0.4 g of acetylene alcohol inhibitor 1-ethynylcyclohexanol, 0.22 g of Karstedt catalyst, mix well, vacuum degassing to obtain a silicone adhesive, pour into a mold, first sulfurize at 60°C for 30 min, then sulfurize at 25°C for 24 h. Cut into test samples; according to GB / T 529-2008 method, test the tear strength. According to GB / T 528-2009 method, test the tensile properties.

[0053] Table 2 Mechanical property test of silicone adhesive

[0054]

[0055]

[0056] The glycidyl ether-based organosilicon polyamide is added as a modifier of the silica adhesive, and has good compatibility with the vinyl polydimethylsiloxane and the hydrogen-containing silicone oil, so that the glycidyl ether-based organosilicon polyamide is uniformly dispersed in the matrix of the silica adhesive. The glycidyl ether-based organosilicon polyamide contains an epoxy group, which can react with the terminal amino group in the nylon polyamide molecular chain in the nylon fiber membrane. The glycidyl ether-based organosilicon polyamide contains an amide group, which can interact with the amide bond in the nylon polyamide molecular chain through hydrogen bonding. The adhesion and the bonding strength between the silica adhesive and the nylon fiber membrane are significantly improved, and the 180° peeling strength reaches 9.7-11.6 N / 25 mm, which shows higher peeling resistance and bonding performance.

[0057] The glycidyl ether-based organosilicon polyamide added in the present application has both rigid polyaramid structure and flexible siloxane structure, and has good compatibility with the vinyl polydimethylsiloxane and the hydrogen-containing silicone oil component in the silica adhesive. When added to the silica adhesive, the tensile properties and the tear strength of the adhesive are significantly improved, and the mechanical properties are higher.

[0058] The silica adhesive of Comparative Example 1 does not contain the glycidyl ether-based organosilicon polyamide, and does not contain an epoxy group and an amide bond in the silica adhesive. The adhesion and the bonding strength between the silica adhesive and the nylon fiber membrane are poor, and the peeling strength is low.

[0059] In Comparative Example 2, 1,3-bis(3-aminopropyl)tetramethyldisiloxane and isophthaloyl chloride are used as polymerization monomers to obtain an organosilicon polyamide. The organosilicon polyamide does not contain an epoxy group, and cannot react with the terminal amino group in the nylon polyamide molecular chain. The peeling strength and the bonding performance between the silica adhesive and the nylon fiber membrane are lower than those of the examples.

[0060] In Comparative Example 3, ethylenediamine and 5-glycidyl ether isophthaloyl chloride are used as polymerization monomers to obtain a glycidyl ether polyamide. The glycidyl ether polyamide does not contain an organosilicon structure, and has poor compatibility with the vinyl polydimethylsiloxane and the hydrogen-containing silicone oil. The dispersibility of the glycidyl ether polyamide in the silica adhesive is poor, and the improvement of the tensile properties and the tear strength of the silica adhesive is lower than that of the examples.

[0061] The above specific examples further illustrate the purpose, technical solutions and advantages of the present application. It should be understood that the above description is only a specific embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A process for preparing a high bond strength silicone-nylon composite material, characterized by, The preparation process is: (1) adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 5-glycidyl ether isophthaloyl chloride, pyridine into N,N-dimethylformamide, stirring and reacting, then adding ethanol for dilution, filtering, washing and drying to obtain glycidyl ether-based silicone polyamide; The preparation method of the 5-glycidyl ether isophthaloyl chloride is: S1, adding 5-hydroxy isophthalic acid dimethyl ester, epichlorohydrin and potassium carbonate into acetone, carrying out microwave reaction in a microwave reaction kettle, filtering, then distilling the filtrate under reduced pressure, washing, dissolving the product in 1,4-dioxane, adding sodium hydroxide aqueous solution to carry out hydrolysis reaction, distilling under reduced pressure, adding hydrochloric acid to adjust the pH to 2-3, precipitating the precipitate, filtering, then recrystallizing the product to obtain 5-glycidyl ether isophthalic acid; S2, adding 5-glycidyl ether isophthalic acid into sulfurous chloride, heating to 60-70°C, reacting for 3-5h, distilling under reduced pressure and drying to obtain 5-glycidyl ether isophthaloyl chloride; wherein the ratio of 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 5-glycidyl ether isophthaloyl chloride and pyridine is 1mol:(0.9-1.1)mol:(0.9-1.1)mol, and the ratio of 5-hydroxy isophthalic acid dimethyl ester, epichlorohydrin and potassium carbonate is 1mol:(3-3.6)mol:(1.5-2)mol; (2) adding glycidyl ether-based silicone polyamide, hydrogen-containing silicone oil, tackifier, acetylene alcohol inhibitor and cast catalyst into vinyl polydimethylsiloxane, uniformly mixing, vacuum degassing to obtain a silicone adhesive, then coating the silicone adhesive on the surface of a nylon fiber membrane and carrying out vulcanization treatment to obtain a high-bond-strength silicone-nylon composite material; In the (2), the ratio of vinyl polydimethylsiloxane, glycidyl ether-based silicone polyamide and hydrogen-containing silicone oil is 100g:(0.5-6)g:(8-9.2)g; the grade of the tackifier is XYS-901; the vulcanization treatment is first carried out at 60-70°C for 30-40min, and then carried out at 20-30°C for 24-36h.

2. The process for preparing high bond strength silicone-nylon composite material according to claim 1, characterized in that, In the (1), the temperature for stirring and reacting is 15-25°C, and the reaction time is 5-8h.

3. The process for preparing high bond strength silicone-nylon composite material according to claim 1, characterized in that, In the S1, the power for microwave reaction is 100-150W, and the reaction time is 15-30min.

4. The process for preparing high bond strength silicone-nylon composite material according to claim 1, characterized in that, In the S1, the mass fraction of sodium hydroxide aqueous solution is 20-35%, the temperature for hydrolysis reaction is 90-100°C, and the reaction time is 8-15h.

5. A high bond strength silicone-nylon composite material, characterized by, The high-bond-strength silicone-nylon composite material is prepared by the preparation process in any one of claims 1-4.

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