CN115491167A - Epoxy modified organic silicon elastic adhesive and preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of adhesives, and particularly relates to an epoxy modified organic silicon elastic adhesive and a preparation method thereof. The epoxy modified organosilicon elastic adhesive comprises the following raw materials in parts by weight: 60-80 parts of elastic epoxy organic silicon copolymer, 20-40 parts of glycidyl ether, 10-60 parts of inorganic filler, 25-35 parts of curing agent and 5-10 parts of accelerator, wherein the structural formula of the elastic epoxy organic silicon copolymer is as follows:

in the formula: r ₁ is-CH ₃ ～‑C ₁₂ H ₂₅ One or more of; r ₂ Is composed of

n is an integer of 10 to 500; r ₃ is-CH ₃ ～‑C ₁₀ H ₂₁ One or more of (a). The epoxy modified organosilicon elastic adhesive provided by the invention solves the problems of large elasticity but low strength of silica gel, large epoxy strength but poor elasticity and low elongation at break.

Description

A kind of epoxy modified silicone elastic adhesive and preparation method thereof

technical field

The invention belongs to the technical field of adhesives, and in particular relates to an epoxy-modified silicone elastic adhesive and a preparation method thereof.

Background technique

Commonly used high-temperature-resistant (above 200°C) adhesives are phenolic resin, polyimide resin, double horse resin, silicone resin, etc., which need to be cured at high temperature and high pressure, which are not suitable for curing at medium temperature and normal pressure, and have strong Radome fields with certain strength requirements.

Epoxy-modified silicone resin can reduce its curing temperature so that it can be cured at medium temperature and normal pressure. At the same time, the temperature resistance level can be further improved by adding high-temperature resistant inorganic fillers. Mica powder and fumed silica are more commonly used High temperature resistant inorganic filler. At present, epoxy-modified silicone resins are generally used in the field of high-temperature resistant coatings, such as epoxy silicone coatings provided by patents CN201310597507.5 and CN201310594314.4, but their temperature resistance is generally below 150°C.

CN03133623.X discloses an epoxy modified silicone resin adhesive, which consists of epoxy modified silicone resin 15-40, epoxy resin 15-35, low molecular polyamide 10-25, filler 10-25, amine Class curing agent 2-8, coupling agent 2-8. The epoxy-modified silicone resin in the epoxy-modified silicone resin adhesive is mainly obtained by grafting or block copolymerization, and has good adhesion to epoxy resin, high mechanical strength, high shear strength and machinability It has the characteristics of good resistance, and at the same time, it has the characteristics of high heat resistance and good elasticity of silicone resin. It can be cured at room temperature, and has the ability of short-term use at 300°C and long-term use at 200°C. However, the shear strength, tensile strength and elongation at break are not satisfactory.

To sum up, although the existing silica gel has high elasticity but low strength, epoxy has high strength but poor elasticity and low elongation at break. In view of this, the present invention is proposed.

Contents of the invention

The object of the present invention is to provide an epoxy-modified silicone elastic adhesive. The epoxy-modified silicone elastic adhesive solves the problems of the existing silica gel with high elasticity but low strength, and epoxy with high strength but poor elasticity and low elongation at break.

For realizing the purpose of the present invention, the present invention adopts following technical scheme:

An epoxy-modified silicone elastic adhesive, comprising the following raw materials in parts by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is one or more of -CH ₃ to -C ₁₂ H ₂₅ ;

n为10～500的整数； _R2 is

n is an integer ranging from 10 to 500;

R ₃ is one or more of -CH ₃ to -C ₁₀ H ₂₁ .

As a preferred version, the epoxy-modified silicone elastic adhesive includes the following raw materials in parts by weight:

Further, the glycidyl ether is trimethylolpropane triglycidyl ether or/and 1,4-butanediol diglycidyl ether, preferably trimethylolpropane triglycidyl ether.

Further, the inorganic filler is one or more of calcium carbonate, silicon micropowder, fumed silica, carbon black, kaolin or talc, preferably a combination of silicon micropowder and fumed silica.

Further, the curing agent is an aromatic amine curing agent.

Further, the aromatic amine curing agent is one or more of m-phenylenediamine, m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone or m-aminomethylamine, preferably For m-xylylenediamine.

Further, the accelerator is 2-mercaptobenzothiazole, cycloalkylimidazoline, 2-phenylimidazoline or 1,8-diazacyclo-bicyclic (5,4,0)-7 -One or more of undecene, preferably 2-mercaptobenzothiazole.

The present invention also provides a preparation method of the epoxy-modified silicone elastic adhesive, wherein the preparation method comprises the following steps:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight portion, stir and mix;

2) After stirring and mixing, stop stirring, control the temperature in the stirring tank, and lower the temperature in the tank to within 40°C;

3) After the temperature of the stirring tank drops below 40°C, add the curing agent and the accelerator according to the weight parts, start stirring again, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Further, in step 1), the stirring speed of the stirring is 55-65 rpm, preferably 60 rpm; the stirring time is 115-125 min, preferably 120 min.

Further, in step 3), the stirring speed of the stirring is 55-65 rpm, preferably 60 rpm; the stirring time is 35-45 min, preferably 40 min.

Further, in step 2) and step 3), the temperature is lowered to within 40°C, preferably within the range of 30-40°C.

Compared with prior art, the present invention has following advantage:

The epoxy-modified silicone elastic adhesive provided by the invention solves the problems of high elasticity but low strength of silica gel, and high epoxy strength but poor elasticity and low elongation at break.

detailed description

The following are specific embodiments of the present invention, and the described examples are for further describing the present invention, rather than limiting the present invention.

Example 1

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -C ₅ H ₁₁ ;

n为100； _R2 is

n is 100;

R ₃ is -C ₅ H ₁₁ .

In this example:

Described glycidyl ether is trimethylolpropane triglycidyl ether;

The inorganic filler is a composition of 25 parts of silicon micropowder and 5 parts of fumed silica;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is m-phenylenediamine;

The accelerator is 2-mercaptobenzothiazole.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight parts, stir at a stirring speed of 60rpm for 120min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirred tank, and lower the temperature in the tank to 38°C;

3) After the temperature of the stirring tank drops to 38°C, add the curing agent and the accelerator according to the weight portion, start stirring again, stir at a stirring speed of 60rpm for 40min, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Example 2

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -CH ₃ ;

n为10； _R2 is

n is 10;

R ₃ is -CH ₃ .

In this example:

Described glycidyl ether is 1,4-butanediol diglycidyl ether;

Described inorganic filler is calcium carbonate;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is m-xylylenediamine;

The accelerator is cycloalkylimidazoline.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight part, stir at a stirring speed of 55rpm for 115min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirred tank, and lower the temperature in the tank to 35°C;

3) After the temperature of the stirring tank drops to 35°C, add the curing agent and the accelerator according to the weight portion, start stirring again, stir at a stirring speed of 55rpm for 35min, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Example 3

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -C ₁₂ H ₂₅ ;

n为500； _R2 is

n is 500;

R ₃ is -C ₁₀ H ₂₁ .

In this example:

Described glycidyl ether is trimethylolpropane triglycidyl ether;

Described inorganic filler is fumed silica;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is diaminodiphenylmethane;

The accelerator is 2-phenylimidazoline.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight parts, stir at a stirring speed of 65rpm for 125min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirring tank, and lower the temperature in the tank to 32°C;

3) After the temperature of the stirring tank drops to 32°C, add the curing agent and the accelerator according to the weight portion, start stirring again, stir at a stirring speed of 65rpm for 45min, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Example 4

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -C ₃ H ₇ ;

n为50； _R2 is

n is 50;

R ₃ is -C ₃ H ₇ .

In this example:

Described glycidyl ether is 1,4-butanediol diglycidyl ether;

Described inorganic filler is carbon black;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is diaminodiphenyl sulfone;

The accelerator is 1,8-diazacyclo-bicyclo(5,4,0)-7-undecene.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirring tank according to the weight part, stir at a stirring speed of 58rpm for 118min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirred tank, and lower the temperature in the tank to 30°C;

3) After the temperature of the stirring tank drops to 30°C, add a curing agent and an accelerator according to the weight portion, start stirring again, stir at a stirring speed of 58 rpm for 38 minutes, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Example 5

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -C ₆ H ₁₁ ;

n为420； _R2 is

n is 420;

R ₃ is -C ₆ H ₁₁ .

In this example:

Described glycidyl ether is trimethylolpropane triglycidyl ether;

Described inorganic filler is kaolin;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is m-aminomethylamine;

The accelerator is 2-phenylimidazoline.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight parts, stir at a stirring speed of 62rpm for 122min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirred tank, and lower the temperature in the tank to 40°C;

3) After the temperature of the stirring tank drops to 40°C, add a curing agent and an accelerator according to the weight portion, start stirring again, stir at a stirring speed of 62 rpm for 42 minutes, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Example 6

The raw material comprises the following components by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula:

R ₁ is -C ₉ H ₁₉ ;

n为160； _R2 is

n is 160;

R ₃ is -C ₉ H ₁₉ .

In this example:

Described glycidyl ether is 1,4-butanediol diglycidyl ether;

Described inorganic filler is talcum powder;

The curing agent is an aromatic amine curing agent; the aromatic amine curing agent is diaminodiphenylmethane;

The accelerator is 2-phenylimidazoline.

The preparation method is as follows:

1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight part, stir at a stirring speed of 53rpm for 123min, and mix well;

2) After stirring and mixing, stop stirring, control the temperature in the stirred tank, and lower the temperature in the tank to 36°C;

3) After the temperature of the stirring tank drops to 36°C, add the curing agent and the accelerator according to the weight portion, start stirring again, stir at a stirring speed of 63rpm for 43min, and mix well to obtain the epoxy-modified silicone elastic adhesive.

Comparative example 1

This comparative example refers to Example 1, and the difference from Example 1 is that the elastic epoxy silicone copolymer used is replaced by commercially available SH-023-4 epoxy-modified silicone resin.

Comparative example 2

This comparative example refers to Example 1, and the difference from Example 1 is that the elastic epoxy silicone copolymer used is replaced by the epoxy-modified silicone compound prepared according to the method in Example 1 of CN113698844A.

Comparative example 3

This comparative example refers to Example 1, and the difference from Example 1 is that the elastic epoxy silicone copolymer used is replaced by the silicone modified epoxy resin (EH-1 ).

Test example 1

This test example investigates the properties of the adhesives prepared in the various embodiments of the present invention and comparative examples.

The testing of each performance is as follows:

Shear strength test: according to GB/T 7124-2008 standard;

Tensile strength test: according to GB/T 528-2009 standard;

Elongation at break test: according to GB/T 528-2009 standard;

Hardness testing: according to GB/T 531.1-2008 standard.

The test results are shown in Table 1 below:

The performance detection result of the adhesive that table 1, each embodiment and comparative example make

Shear strength (MPa) Tensile strength (MPa) Elongation at break (%) Hardness (Shore A) Example 1 18.7 20.1 154% 75 Example 2 18.4 19.8 151% 73 Example 3 18.5 19.9 152% 74 Example 4 18.3 19.6 150% 71 Example 5 18.1 19.5 149% 72 Example 6 18.5 19.7 148% 73 Comparative example 1 13.2 14.1 102% 55 Comparative example 2 12.8 13.9 98% 50 Comparative example 3 11.9 13.1 89% 48

Claims (10)

1. an epoxy-modified silicone elastic adhesive, characterized in that, the epoxy-modified organic silicon elastic adhesive comprises the following raw materials in parts by weight:

Wherein, the structural formula of described elastic epoxy silicone copolymer is as follows:

In the formula: R ₁ is one or more of -CH ₃ to -C ₁₂ H ₂₅ ; _R2 is

n is an integer ranging from 10 to 500; R ₃ is one or more of -CH ₃ to -C ₁₀ H ₂₁ . 2. The epoxy-modified silicone elastic adhesive according to claim 1, characterized in that, the epoxy-modified silicone elastic adhesive comprises the following raw materials in parts by weight:

3. epoxy-modified organic silicon elastic adhesive according to claim 1 or 2, is characterized in that, The glycidyl ether is trimethylolpropane triglycidyl ether or/and 1,4-butanediol diglycidyl ether, preferably trimethylolpropane triglycidyl ether. 4. epoxy-modified silicone elastic adhesive according to claim 1 or 2, is characterized in that, The inorganic filler is one or more of calcium carbonate, microsilica powder, fumed silica, carbon black, kaolin or talc, preferably a combination of microsilica powder and fumed silica. 5. epoxy-modified silicone elastic adhesive according to claim 1 or 2, is characterized in that, The curing agent is an aromatic amine curing agent. 6. epoxy-modified silicone elastic adhesive according to claim 5, is characterized in that, The aromatic amine curing agent is one or more of m-phenylenediamine, m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone or m-aminomethylamine, preferably m-phenylene Dimethylamine. 7. epoxy-modified organic silicon elastic adhesive according to claim 1 or 2, is characterized in that, The accelerator is 2-mercaptobenzothiazole, cycloalkylimidazoline, 2-phenylimidazoline or 1,8-diazacyclic-bicyclic (5,4,0)-7-undeca One or more of carbene, preferably 2-mercaptobenzothiazole. 8. a preparation method of the epoxy-modified silicone elastic adhesive described in any one of claims 1-7, is characterized in that, described preparation method comprises the steps: 1) Add elastic epoxy silicone copolymer, glycidyl ether and inorganic filler in the stirred tank according to the weight portion, stir and mix; 2) After stirring and mixing, stop stirring, control the temperature in the stirring tank, and lower the temperature in the tank to within 40°C; 3) After the temperature of the stirring tank drops below 40°C, add the curing agent and the accelerator according to the weight parts, start stirring again, and mix well to obtain the epoxy-modified silicone elastic adhesive. 9. The preparation method according to claim 8, characterized in that, in step 1), the stirring speed of the stirring is 55-65 rpm, preferably 60 rpm; the stirring time is 115-125 min, preferably 120 min. 10. The preparation method according to claim 8, characterized in that, in step 3), the stirring speed of the stirring is 55-65 rpm, preferably 60 rpm; the stirring time is 35-45 min, preferably 40 min.