Low viscosity and high thermal conductivity organosilicon gel and preparation method thereof

[0024] Example 1

[0025] A low-viscosity and high-thermal-conductivity silicone gel. The low-viscosity and high-thermal-conductivity silicone gel is composed of component A and component B, wherein component A includes the following components by mass: 100 parts of vinyl silicone oil, 5 parts of polyvinyl silicone oil, 5 parts of alkyl modified silicone oil, 5 parts of active diluent, 500 parts of high thermal conductivity compound inorganic filler, 1 part of catalyst and 2 parts of pigment, component B includes the following components by mass: 100 parts vinyl silicone oil, 5 parts polyvinyl silicone oil, 5 parts alkyl modified silicone oil, 5 parts active diluent, 500 parts high thermal conductivity compound inorganic filler, 1 part hydrogen-containing silicone oil, 0.5 part inhibitor, 0.5 part increase Adhesive. The vinyl silicone oil is vinyl terminated polydimethylsiloxane, the vinyl mass content is between 0.2%, and the viscosity is 30 mPa·s. The polyvinyl silicone oil is methyl terminated polysiloxane containing vinyl in the side chain, the vinyl mass content is 0.5%, and the viscosity is 100 mPa·s. The alkyl modified silicone oil is a long carbon chain alkyl grafted polydimethylsiloxane. The reactive diluent is single-end vinyl polysiloxane. The high thermal conductivity compound inorganic filler is alumina and calcium carbonate. The high thermal conductivity compound inorganic filler is spherical or quasi-spherical thermally conductive particles with a particle size of 0.3-100μm, wherein the particle size is 0.3-1μm accounting for 1% of the total, and the particle size is 3-30μm accounting for the total 60%, the particle size is 50-100μm, accounting for 1% of the total, and the remaining particle size is between 1-3μm and 30-50μm. The high thermal conductivity compound inorganic filler is surface-modified by a long-chain alkyl silane coupling agent, and the oil absorption value is between 3-10%. The hydrogen-containing silicone oil is a mixture of hydrogen-terminated polysiloxane and side chain hydrogen-containing polysiloxane, wherein the mass ratio of the hydrogen-terminated polysiloxane and the side chain hydrogen-containing polysiloxane is 1:1. The hydrogen-containing silicone oil is a low-viscosity hydrogen-containing polysiloxane with a viscosity of 10 mPa·s. The catalyst is chloroplatinic acid and its chelate compound, which are commonly used in addition type liquid silicone rubber. The inhibitor and the tackifier are known inhibitors and tackifiers, respectively. The pigment is iron red.

[0026] The preparation method of the aforementioned low-viscosity and high-thermal-conductivity silicone gel includes the following steps:

[0027] Step 1. The semi-finished product is premixed and removed. The vinyl silicone oil, polyvinyl silicone oil, and high thermal conductivity compound inorganic filler are weighed and added to the planetary mixer according to the ratio. At 120℃, vacuum and mix evenly with -0.1MPa for use ;

[0028] Step 2. Finished product preparation, after the semi-finished product is cooled to room temperature, weigh the other materials of component A and component B into the planetary mixer according to the ratio, vacuum at -0.1MPa, and stir at 40rpm for 45min;

[0029] Step 3. Divide, put the mixed A component and B component into a 1:1 two-component tube or barrel.

[0030] Example 2

[0031] A low-viscosity and high-thermal-conductivity silicone gel. The low-viscosity and high-thermal-conductivity silicone gel is composed of component A and component B, wherein component A includes the following components by mass: 100 parts of vinyl silicone oil, 20 parts of polyvinyl silicone oil, 20 parts of alkyl-modified silicone oil, 25 parts of active diluent, 2500 parts of high thermal conductivity compound inorganic filler, 10 parts of catalyst and 10 parts of pigment, component B includes the following components by mass: 100 parts vinyl silicone oil, 20 parts polyvinyl silicone oil, 20 parts alkyl modified silicone oil, 25 parts active diluent, 2500 parts high thermal conductivity compound inorganic filler, 20 parts hydrogen-containing silicone oil, 10 parts inhibitor, 10 parts increase Adhesive. The vinyl silicone oil is vinyl-terminated polydimethylsiloxane, polydimethyl-methylvinylsiloxane and polymethylphenyl-methylvinylsiloxane, and the vinyl mass content is within 0.8%, viscosity is 1000mPa·s. The polyvinyl silicone oil is methyl terminated polysiloxane containing vinyl in the side chain, the vinyl mass content is 5%, and the viscosity is 2000 mPa·s. The alkyl modified silicone oil is a long carbon chain alkyl grafted polydimethylsiloxane. The reactive diluent is a single-end vinyl polysiloxane. The high thermal conductivity compound inorganic filler is aluminum oxide, magnesium oxide, zinc oxide, beryllium oxide, aluminum nitride, boron nitride, silicon nitride, silicon carbide, aluminum hydroxide, silicon dioxide, calcium carbonate and silicate Class inorganic powder. The high thermal conductivity compound inorganic filler is spherical or quasi-spherical thermally conductive particles with a particle size of 0.3-100 μm, wherein the particle size of 0.3-1 μm accounts for 5% of the total, and the particle size of 3-30 μm accounts for the total 80%, the particle size is 50-100μm, accounting for 10% of the total, the remaining particle size is between 1-3μm and 30-50μm. The high thermal conductivity compound inorganic filler is surface-modified by a long-chain alkyl silane coupling agent, and the oil absorption value is between 3-10%. The hydrogen-containing silicone oil is a mixture of hydrogen-terminated polysiloxane and side chain hydrogen-containing polysiloxane, wherein the mass ratio of the hydrogen-terminated polysiloxane and the side chain hydrogen-containing polysiloxane is 30:1. The hydrogen-containing silicone oil is a low-viscosity hydrogen-containing polysiloxane with a viscosity of 150 mPa·s. The catalyst is an addition type liquid silicone rubber. The commonly used catalyst is a soluble platinum compound. The inhibitor and the tackifier are known inhibitors and tackifiers, respectively. The pigment is cobalt blue.

[0032] The preparation method of the aforementioned low-viscosity and high-thermal-conductivity silicone gel includes the following steps:

[0033] Step 1. The semi-finished product is premixed and removed. The vinyl silicone oil, polyvinyl silicone oil, and high thermal conductivity compound inorganic filler are weighed and added to the planetary mixer according to the ratio. At 120℃, vacuum and mix evenly with -0.1MPa for use ;

[0034] Step 2. Finished product preparation, after the semi-finished product is cooled to room temperature, weigh the other materials of component A and component B into the planetary mixer according to the ratio, vacuum at -0.1MPa, and stir at 40rpm for 45min;

[0035] Step 3. Divide, put the mixed A component and B component into a 1:1 two-component tube or barrel.

[0036] Example 3

[0037] A low-viscosity and high-thermal-conductivity silicone gel. The low-viscosity and high-thermal-conductivity silicone gel is composed of component A and component B, wherein component A includes: 70g of vinyl-terminated polyethylene with a viscosity of 50 mPa·s Methylsiloxane, 30g of polydimethyl-methylvinylsiloxane with a viscosity of 250mPa·s vinyl-terminated, 5g of polyvinyl silicone oil with a viscosity of 500mPa·s, and the polyvinyl End and side chains contain vinyl polysiloxane, 20g alkyl-modified silicone oil, the alkyl-modified silicone oil is long-carbon chain alkyl grafted polydimethylsiloxane, 20g reactive diluent, the active The diluent is single-ended vinyl polysiloxane, 2300g of high thermal conductivity compound inorganic filler treated with long chain alkyl silane, oil absorption value is 4%, which contains 1900g spherical alumina (with a particle size of 100μm accounting for 5%, 70μm accounts for 10%, 30μm accounts for 80%, 1μm accounts for 5%), 200g spherical aluminum hydroxide with a particle size of 20μm, 100g boron nitride with a particle size of 40μm, 100g spherical aluminum nitride with a particle size of 30μm, 20g chloroplatinum Acid and 6g cobalt blue. The B component includes: 70g vinyl-terminated polydimethylsiloxane with a viscosity of 50mPa·s, 30g vinyl-terminated polydimethyl-methylvinylsiloxane with a viscosity of 250mPa·s, 5g viscosity 500mPa·s polyvinyl silicone oil, the polyvinyl silicone oil is methyl-terminated, side chain-containing vinyl polysiloxane, 20g alkyl modified silicone oil, the alkyl modified silicone oil is a long carbon chain alkyl group Grafted polydimethylsiloxane, 20g reactive diluent, the reactive diluent is single-end vinyl polysiloxane, 2300g high thermal conductivity compound inorganic filler treated with long-chain alkyl silane, oil absorption value 4 %, which contains 1900g spherical alumina (with a particle size of 100μm accounting for 5%, 70μm accounting for 10%, 30μm accounting for 80%, and 1μm accounting for 5%), 200g of spherical aluminum hydroxide with a particle size of 20μm, and 100g with a particle size of 40μm Boron nitride, 100g spherical aluminum nitride with a particle size of 30μm, 20g hydrogen-containing silicone oil (the mass ratio of the end hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is 20:1), the hydrogen-containing silicone oil is a low-viscosity hydrogen-containing polysilicon Oxyane, 3g inhibitor and 3g thickener, the inhibitor and thickener are currently known inhibitors and thickeners, respectively.

[0038] The preparation method of the aforementioned low-viscosity and high-thermal-conductivity silicone gel includes the following steps:

[0039] Step 1. The semi-finished product is premixed and removed. The vinyl silicone oil, polyvinyl silicone oil, and high thermal conductivity compound inorganic filler are weighed and added to the planetary mixer according to the ratio. At 120℃, vacuum and mix evenly with -0.1MPa for use ;

[0040] Step 2. Finished product preparation, after the semi-finished product is cooled to room temperature, weigh the other materials of component A and component B into the planetary mixer according to the ratio, vacuum at -0.1MPa, and stir at 40rpm for 45min;

[0041] Step 3. Divide, put the mixed A component and B component into a 1:1 two-component tube or barrel.