A preparation method of anti-poisoning silicone potting glue

Abstract

The present invention discloses a preparation method of an anti-poisoning organosilicon potting adhesive, which belongs to the field of organosilicon technology. Operation steps: (1) a coupling agent is dispersed in an ethanol solution to form a hydrolyzate; ammonium polyphosphate and anhydrous ethanol are uniformly mixed to form an ammonium polyphosphate suspension; the hydrolyzate is slowly dripped into the ammonium polyphosphate suspension to react, and modified ammonium polyphosphate is prepared; (2) modified ammonium polyphosphate is added to vinyl silicone oil, and other auxiliary agents are added to prepare an organosilicon-based adhesive; (3) the organosilicon-based adhesive is mixed with a platinum catalyst to obtain component A, the organosilicon-based adhesive is mixed with hydrogenated silicone oil and an inhibitor to obtain component B, and the component A is mixed with component B to obtain an anti-poisoning organosilicon potting adhesive. The viscosity of the anti-poisoning organosilicon potting adhesive of the present invention is 5000-9600mPa.s, which has a good potting effect; the curing time is 45-70min, which effectively avoids the filler sedimentation problem caused by long-term curing, and the flame retardant grade (UL-94) is V-1 or V-0, reflecting an excellent flame retardant effect.

Description

Technical Field

[0001] The invention belongs to the technical field of organic silicon, and particularly relates to a method for preparing an anti-poisoning organic silicon potting adhesive. Background Art

[0002] In recent years, new energy vehicles have developed rapidly, and research on batteries in their power systems has become increasingly in-depth. However, in practical applications, they may face various safety incidents caused by factors such as temperature, heat concentration, and violent collisions. Silicone potting compounds can provide sealing protection in battery systems. After curing, they provide waterproofing, moisture-proofing, dustproofing, insulation, and shockproofing. However, to achieve flame retardancy, silicone potting compounds in the market often add large amounts of inorganic flame retardants, which significantly increases the viscosity and results in poor potting effectiveness. Alternatively, halogen-based flame retardants are used, causing significant pollution. High-polymerization ammonium polyphosphate is widely used in intumescent fire retardant coatings, polyethylene, polypropylene, polyurethane, epoxy resin, and rubber products. It is a safe, efficient, non-halogen smoke suppressant flame retardant. However, when two-component addition-type liquid silicone rubber comes into contact with ammonium polyphosphate, the platinum catalyst required for the hydrosilylation reaction is easily poisoned, preventing the potting compound from curing, thus limiting its application in silicone potting compounds. Summary of the Invention

[0003] In order to solve the problem of platinum catalyst poisoning and achieve reliable flame retardant and potting effects, the present invention provides a method for preparing an anti-poisoning organosilicon potting adhesive.

[0004] The preparation steps of an anti-poisoning silicone potting adhesive are as follows:

[0005] (1) Preparation of modified ammonium polyphosphate

[0006] Disperse 5g or 30g of coupling agent in 20g or 120g of 80% ethanol solution to form a hydrolyzate, and hydrolyze at room temperature;

[0007] The coupling agent is one of vinyltriethoxysilane, γ-glycidoxytrimethylsilane, propyltriethoxysilane, and monoalkoxy titanium tricarboxylate;

[0008] 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed to form an ammonium polyphosphate suspension;

[0009] At 40°C or 60°C, slowly dripping the hydrolyzate into the ammonium polyphosphate suspension and continuing the reaction for 2h or 4h;

[0010] The reactants are washed and dried to obtain modified ammonium polyphosphate;

[0011] (2) Preparation of silicone-based adhesive

[0012] Add 200g or 500g of modified ammonium polyphosphate and 400g or 800g of additives to 1000g of vinyl silicone oil and mix well to obtain a silicone-based adhesive;

[0013] The auxiliary agent is one of low melting point glass powder, montmorillonite and mica powder;

[0014] (3) Preparation of anti-poisoning silicone potting glue

[0015] 100 g of silicone-based adhesive and 0.2 g of platinum catalyst were mixed to obtain component A;

[0016] 100 g of silicone-based adhesive, 2 g or 5 g of hydrogenated silicone oil, and 0.001 g or 0.003 g of inhibitor were mixed to obtain component B;

[0017] The inhibitor is one of 1-ethynylcyclohexanol, 2-ethylyn-2-ol, 1-ethynyl-1-cyclopentanol, and 1-ethynyl-1-cyclohexanol;

[0018] Mix component A and component B evenly in a mass ratio of 1:0.8 or 1:1.2 to obtain an anti-poisoning silicone potting compound;

[0019] The anti-poisoning silicone potting glue has a viscosity of 5000-9600 mPa.s, a curing time of 45-70 min, a limiting oxygen index LOI of 27.8-30.5, a hardness of 22-40 Shore A, and a flame retardant grade (UL-94) of V-1 or V-0.

[0020] The technical solutions are further defined as follows:

[0021] In step (1), the coupling agent hydrolysis conditions are: hydrolysis temperature 25°C or 40°C, and hydrolysis time 30min or 60min.

[0022] In step (1), the dispersion time of the ammonium polyphosphate suspension is 30 min or 60 min.

[0023] In step (3), the platinum catalyst is a Karstedt catalyst, and the platinum content is 1000 ppm or 5000 ppm.

[0024] In step (3), the hydrogen content of the hydrogen-containing silicone oil is 0.5% or 1.0%.

[0025] The beneficial technical effects of the present invention are embodied in the following aspects:

[0026] (1) The anti-poisoning silicone potting adhesive prepared by the present invention has a viscosity of 5000 to 9600 mPa.s, thus having a good potting effect. Its curing time is 45 to 70 minutes, which effectively avoids the filler sedimentation problem caused by long-term curing. Its limiting oxygen index LOI is 27.8 to 30.5, its hardness is 22 to 40 Shore A, and its flame retardant grade (UL-94) is V-1 or V-0, reflecting an excellent flame retardant effect.

[0027] (2) The present invention modifies the surface of ammonium polyphosphate, an environmentally friendly and flame-retardant non-halogen flame retardant, so that a coupling agent is bonded to its surface to generate a strong chemical bond interaction, which greatly reduces the electron-donating effect of ammonium polyphosphate. The platinum catalyst activity required for the curing of the potting glue comes from the strong reducing property of the vinyl group in its complex structure, which makes the platinum present in a zero-valent state. The O in ammonium polyphosphate — The coordination effect between vinyl and platinum is destroyed, and the modified ammonium polyphosphate surface forms a covalent bond with the coupling agent, reducing the exposure of anionic charges on the surface of ammonium polyphosphate, thereby reducing the interaction with the platinum catalyst and the impact on the catalytic activity during the silicone curing process, so that the silicone potting compound can finally be cured in a shorter time.

[0028] (3) After the modified ammonium polyphosphate is bonded with a coupling agent, the connection with the vinyl silicone oil chain segment can be enhanced, thereby improving the compatibility with the silicone matrix and effectively reducing the viscosity of the potting compound. When it burns, it decomposes to produce acidic substances and gases such as phosphoric acid, polyphosphoric acid, and metaphosphoric acid. The surface coupling agent itself also contains good flame retardant elements, which synergistically promote carbonization with ammonium polyphosphate, thereby having a good flame retardant effect. The preparation method of the potting compound is simple, safe and efficient, and the potting effect is good. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to specific embodiments.

[0030] Example 1

[0031] The preparation steps of an anti-poisoning silicone potting adhesive are as follows:

[0032] (1) Preparation of modified ammonium polyphosphate

[0033] Disperse 5g of vinyl triethoxysilane coupling agent in 20g of 80% ethanol solution to form a hydrolyzate, with a hydrolysis temperature of 25°C and a hydrolysis time of 30min;

[0034] 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed for 30 minutes to form an ammonium polyphosphate suspension;

[0035] The hydrolyzed solution was slowly dripped into the ammonium polyphosphate suspension at 40° C. and the reaction was continued for 2 hours; the reactant was washed and dried to obtain modified ammonium polyphosphate.

[0036] (2) Preparation of silicone-based adhesive

[0037] 200 g of modified ammonium polyphosphate was added to 1000 g of vinyl silicone oil, and then 400 g of low-melting-point glass powder additive was added, and the mixture was mixed evenly to obtain a silicone-based adhesive.

[0038] (3) Preparation of anti-poisoning silicone potting glue

[0039] 100 g of an organic silicon-based adhesive and 0.2 g of a platinum catalyst having a platinum content of 1000 ppm were mixed to obtain component A; 100 g of an organic silicon-based adhesive, 2 g of a hydrogenated silicone oil having a hydrogen content of 0.5%, and 0.001 g of a 1-ethynylcyclohexanol inhibitor were mixed to obtain component B;

[0040] Component A and component B are mixed evenly in a mass ratio of 1:0.8 to obtain an anti-poisoning silicone potting compound;

[0041] Viscosity test and thermal analysis test are carried out on the anti-poisoning silicone potting compound at room temperature. The anti-poisoning effect of the potting compound is judged by observing the viscosity change trend, curing time, curing degree, etc. After curing, the samples are prepared for oxygen index test and vertical burning test to judge the flame retardant effect.

[0042] The anti-poisoning silicone potting adhesive of Example 1 has a viscosity of 5000 mPa.s, a curing time of 70 min, a limiting oxygen index LOI of 28.4, a hardness (Shore A) of 27, and a flame retardant grade (UL-94) of V-1.

[0043] Example 2

[0044] The preparation steps of an anti-poisoning silicone potting adhesive are as follows:

[0045] (1) Preparation of modified ammonium polyphosphate

[0046] Disperse 5g of γ-glycidoxytrimethylsilane coupling agent in 20g of 80% ethanol solution to form a hydrolyzate at 25°C for 30min.

[0047] 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed for 30 minutes to form an ammonium polyphosphate suspension;

[0048] The hydrolyzed solution was slowly dripped into the ammonium polyphosphate suspension at 40° C. and the reaction was continued for 2 hours; the reactant was washed and dried to obtain modified ammonium polyphosphate.

[0049] (2) Preparation of silicone-based adhesive

[0050] 200 g of modified ammonium polyphosphate was added to 1000 g of vinyl silicone oil, and then 400 g of low-melting-point glass powder additive was added, and the mixture was mixed evenly to obtain a silicone-based adhesive.

[0051] (3) Preparation of anti-poisoning silicone potting glue

[0052] 100 g of an organic silicon-based adhesive and 0.2 g of a platinum catalyst having a platinum content of 1000 ppm were mixed to obtain component A; 100 g of an organic silicon-based adhesive, 2 g of a hydrogenated silicone oil having a hydrogen content of 0.5%, and 0.001 g of a 2-ethylyn-2-ol inhibitor were mixed to obtain component B;

[0053] Component A and component B are mixed evenly in a mass ratio of 1:0.8 to obtain an anti-poisoning silicone potting compound;

[0054] Viscosity test and thermal analysis test are carried out on the anti-poisoning silicone potting compound at room temperature. The anti-poisoning effect of the potting compound is judged by observing the viscosity change trend, curing time, curing degree, etc. After curing, the samples are prepared for oxygen index test and vertical burning test to judge the flame retardant effect.

[0055] The anti-poisoning silicone potting adhesive of Example 2 has a viscosity of 6200 mPa.s, a curing time of 60 min, a limiting oxygen index LOI of 27.8, a hardness (Shore A) of 22, and a flame retardant grade (UL-94) of V-1.

[0056] Example 3

[0057] The preparation steps of an anti-poisoning silicone potting adhesive are as follows:

[0058] (1) Preparation of modified ammonium polyphosphate

[0059] 30g of propyltriethoxysilane coupling agent was dispersed in 120g of 80% ethanol solution to form a hydrolyzate, the hydrolysis temperature was 40°C, and the hydrolysis time was 60min;

[0060] 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed for 60 minutes to form an ammonium polyphosphate suspension;

[0061] The hydrolyzed solution was slowly dripped into the ammonium polyphosphate suspension at 60° C. and the reaction was continued for 4 hours; the reactant was washed and dried to obtain modified ammonium polyphosphate.

[0062] (2) Preparation of silicone-based adhesive

[0063] 500 g of modified ammonium polyphosphate was added to 1000 g of vinyl silicone oil, and then 800 g of montmorillonite additive was added, and the mixture was mixed evenly to obtain a silicone-based adhesive.

[0064] (3) Preparation of anti-poisoning silicone potting glue

[0065] 100 g of an organic silicon-based adhesive and 0.2 g of a platinum catalyst having a platinum content of 5000 ppm were mixed to obtain component A; 100 g of an organic silicon-based adhesive, 5 g of a hydrogenated silicone oil having a hydrogen content of 1.0%, and 0.003 g of a 1-ethynyl-1-cyclopentanol inhibitor were mixed to obtain component B;

[0066] Mix component A and component B evenly in a mass ratio of 1:1.2 to obtain an anti-poisoning silicone potting compound;

[0067] Viscosity test and thermal analysis test are carried out on the anti-poisoning silicone potting compound at room temperature. The anti-poisoning effect of the potting compound is judged by observing the viscosity change trend, curing time, curing degree, etc. After curing, the samples are prepared for oxygen index test and vertical burning test to judge the flame retardant effect.

[0068] The anti-poisoning silicone potting adhesive of Example 3 has a viscosity of 8800 mPa.s, a curing time of 45 min, a limiting oxygen index LOI of 29.3, a hardness (Shore A) of 40, and a flame retardant grade (UL-94) of V-0.

[0069] Example 4

[0070] The preparation steps of an anti-poisoning silicone potting adhesive are as follows:

[0071] (1) Preparation of modified ammonium polyphosphate

[0072] 30g of monoalkoxy tricarboxylic acid titanium coupling agent was dispersed in 120g of 80% ethanol solution to form a hydrolyzed solution, the hydrolysis temperature was 40°C, and the hydrolysis time was 60min;

[0073] 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed for 60 minutes to form an ammonium polyphosphate suspension;

[0074] The hydrolyzed liquid was slowly dripped into the ammonium polyphosphate suspension at 60° C., and the reaction was continued for 4 hours; the reactant was washed and dried to obtain modified ammonium polyphosphate.

[0075] (2) Preparation of silicone-based adhesive

[0076] Add 500 g of modified ammonium polyphosphate to 1000 g of vinyl silicone oil, then add 800 g of mica powder as an additive, mix well, and obtain a silicone-based adhesive.

[0077] (3) Preparation of anti-poisoning silicone potting glue

[0078] 100 g of an organic silicon-based adhesive and 0.2 g of a platinum catalyst having a platinum content of 5000 ppm were mixed to obtain component A; 100 g of an organic silicon-based adhesive, 5 g of a hydrogenated silicone oil having a hydrogen content of 1.0%, and 0.003 g of a 1-ethynyl-1-cyclohexanol inhibitor were mixed to obtain component B;

[0079] Mix component A and component B evenly in a mass ratio of 1:1.2 to obtain an anti-poisoning silicone potting compound;

[0080] Viscosity test and thermal analysis test are carried out on the anti-poisoning silicone potting compound at room temperature. The anti-poisoning effect of the potting compound is judged by observing the viscosity change trend, curing time, curing degree, etc. After curing, the samples are prepared for oxygen index test and vertical burning test to judge the flame retardant effect.

[0081] The anti-poisoning silicone potting adhesive of Example 4 has a viscosity of 9600 mPa.s, a curing time of 50 min, a limiting oxygen index LOI of 29.3, a hardness (Shore A) of 36, and a flame retardant grade (UL-94) of V-0.

[0082] Comparative Example 1

[0083] An organosilicon potting compound was prepared in the same manner as in Example 1, except that the ammonium polyphosphate was not modified.

[0084] The performance tests of the silicone potting compounds prepared in Examples 1-4 and Comparative Example 1 were conducted as follows: Viscosity: The viscosity of the two components of the potting compound was tested at 25° C. after being evenly mixed according to GB / T 2794-2013; Flame retardancy: The flame retardancy of the potting compound after curing was tested according to ANSI / UL94-1985;

[0085] Hardness: Test the hardness of the potting compound after curing according to GB / T 531.1-2008.

[0086] The viscosity of the anti-poisoning silicone potting glue in this comparative example 1 is 5600 mPa.s, and it is uncured, has a limiting oxygen index LOI of no, a hardness (Shore A) of no, and a flame retardant grade (UL-94) of no.

[0087] Table 1

[0088] Table 1 shows the technical requirements of the anti-poisoning silicone potting adhesives prepared in Examples 1-4 and the products prepared in the comparative example.

[0089] It is easy for those skilled in the art to understand that the above embodiments 1-4 are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing an anti-poisoning silicone potting compound, characterized in that: The steps are as follows: (1) Preparation of modified ammonium polyphosphate Disperse 5g or 30g of coupling agent in 20g or 120g of 80% ethanol solution to form a hydrolyzate, and hydrolyze at room temperature; The coupling agent is one of vinyltriethoxysilane, γ-glycidoxytrimethylsilane, propyltriethoxysilane, and monoalkoxy titanium tricarboxylate; 1000g of ammonium polyphosphate and 800g of anhydrous ethanol were uniformly mixed and dispersed to form an ammonium polyphosphate suspension; At 40°C or 60°C, slowly dripping the hydrolyzate into the ammonium polyphosphate suspension and continuing the reaction for 2h or 4h; The reactants are washed and dried to obtain modified ammonium polyphosphate; (2) Preparation of silicone-based adhesive Add 200g or 500g of modified ammonium polyphosphate and 400g or 800g of additives to 1000g of vinyl silicone oil and mix well to obtain a silicone-based adhesive; The auxiliary agent is one of low melting point glass powder, montmorillonite and mica powder; (3) Preparation of anti-poisoning silicone potting glue 100 g of silicone-based adhesive and 0.2 g of platinum catalyst were mixed to obtain component A; 100 g of silicone-based adhesive, 2 g or 5 g of hydrogenated silicone oil, and 0.001 g or 0.003 g of inhibitor were mixed to obtain component B; The inhibitor is one of 1-ethynylcyclohexanol, 2-ethylyn-2-ol, and 1-ethynyl-1-cyclopentanol; Mix component A and component B evenly in a mass ratio of 1:0.8 or 1:1.2 to obtain an anti-poisoning silicone potting compound; The anti-poisoning silicone potting adhesive has a viscosity of 5000-9600 mPa.s, a curing time of 45-70 min, a limiting oxygen index (LOI) of 27.8-30.5, a hardness of 22-40 Shore A, and a flame retardant grade of UL-94 of V-1 or V-0.

2. The method for preparing the anti-poisoning silicone potting adhesive according to claim 1, wherein: In step (1), the coupling agent hydrolysis conditions are: hydrolysis temperature 25°C or 40°C, and hydrolysis time 30min or 60min.

3. The method for preparing the anti-poisoning silicone potting adhesive according to claim 1, characterized in that: In step (1), the dispersion time of the ammonium polyphosphate suspension is 30 min or 60 min.

4. The method for preparing the anti-poisoning silicone potting adhesive according to claim 1, wherein: In step (3), the platinum catalyst is a Karstedt catalyst, and the platinum content is 1000 ppm or 5000 ppm.

5. The method for preparing the anti-poisoning silicone potting adhesive according to claim 1, characterized in that: In step (3), the hydrogen content of the hydrogen-containing silicone oil is 0.5% or 1.0%.

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