Silicone rubber foam material and preparation method thereof

Abstract

The invention relates to a silicone rubber foam material and a preparation method thereof. The preparation method comprises the following steps: preparing polydimethylsiloxane, boric acid, a derivative thereof and an organic solvent into a polydimethylsiloxane solution, carrying out condensation polymerization, and then removing unreacted boric acid, the derivative thereof and the organic solvent to obtain shear thickening gel; mixing 1-10 parts by mass of the shear thickening gel with 100 parts by mass of vinyl-containing silicone rubber to obtain a silicone rubber base material; mixing the silicone rubber base material with 1-20 parts by mass of nanocellulose, 1-10 parts by mass of expanded microspheres and 0.01-0.5 part by mass of an organic peroxide cross-linking agent, so as to obtain silicone rubber compound; and performing pre-forming and cross-linking foaming on the silicone rubber compound to obtain the silicone rubber foaming material. The silicone rubber foam material obtained by the preparation method has the advantages of high resilience, low compression deformation and the like, and can be better applied to the fields of shock absorption and impact resistance.

Description

Technical field

[0001] The present invention relates to the technical field of foam materials, in particular to a silicone rubber foam material and a method of preparation thereof. Background

[0002] Compared with traditional impact-resistant materials, shear thickening materials have excellent damping properties and reversible soft-to-hard conversion characteristics. In its natural state, the shear thickening material maintains good flexibility and, when subjected to impact, it can quickly harden against impact.

[0003] Shear thickening materials can be divided into shear thickening gel and shear thickening liquid, of which the shear thickening gel has better structural stability and high and low temperature resistance. However, due to the strong cold flow characteristics of the shear thickening gel, it is impossible to maintain its original shape in its natural state. Therefore, in traditional techniques, porous materials are often used as a skeleton to coat the shear thicken...

Examples

preparation example Construction

[0023] The preparation method of the silicone rubber foam material provided in the present invention comprises the following steps:

[0024] S1, the polydimethylsiloxane, boric acid and its derivatives and organic solvents are formulated into a polydimethylsiloxane solution, and polycondensation reaction is carried out, and then the unreacted boric acid and its derivatives and the organic solvent are removed to give a shear thickening gel;

[0025] S2, the shear thickening gel of 1 mass part -10 mass parts is mixed with 100 mass parts of silicone rubber containing vinyl to obtain a silicone rubber binder;

[0026] S3, the silicone rubber binder with 1 mass part -20 mass nanocellulose, 1 mass part -10 mass parts of the expanded microspheres, 0.01 mass part -0.5 mass part of the organic peroxide crosslinker for mixing, to obtain silicone rubber compound; and

[0027] S4, the silicone rubber compound is pre-formed and cross-linked foamed to obtain a silicone rubber foam material.

[...

Embodiment 1

[0049] 10 mass parts of hydroxyl-terminated dimethicone (kinematic viscosity of 65cSt), 0.5 parts of dried boric acid, 89.5 parts of mass toluene were added to the sealed container in turn, stirred at a speed of 120 rpm at 60 °C for 120 min, to obtain a uniform hydroxyl end polydimethylsiloxane solution, and the hydroxyl end polydimethylsiloxane solution was heated to 120 °C for condensation reaction, and the reaction was 12h at a stirring speed of 120 rpm. Polyborosiloxane solution is obtained. Then, the polyborosiloxane solution was filtered out of the unreacted boric acid particles with a pore size of 0.44 μm, the filtrate was poured into a glass dish, and placed in a vacuum oven at 80 °C, -3 MPa to dry for 24 h, the toluene was removed, and the shear thickening gel was obtained.

[0050] 100 parts of methyl vinyl silicone rubber (hardness 40A, molecular weight of 50×10 4g / mol, the molar fraction of vinyl is 0.55%), 10 mass shear thickening gel was added to the vacuum kneadin...

Embodiment 2

[0054] 10 mass parts of hydroxyl-terminated dimethicone (kinematic viscosity of 75cSt), 0.5 parts of dried boric acid, 89.5 parts of mass toluene were added to the sealed container in turn, stirred at a speed of 120 rpm at 60 ° C for 120 min, to obtain a uniform hydroxyl-terminated dimethicone solution, and the hydroxyl end polydimethylsiloxane solution was heated to 120 ° C for condensation reaction, and reacted at a stirring speed of 120 rpm for 12 h. Polyborosiloxane solution is obtained. Then, the polyborosiloxane solution was filtered out of the unreacted boric acid particles with a pore size of 0.44 μm, the filtrate was poured into a glass dish, and placed in a vacuum oven at 80 °C, -3 MPa to dry for 24 h, the toluene was removed, and the shear thickening gel was obtained.

[0055] 100 parts of methyl vinyl silicone rubber (hardness 40A, molecular weight of 50×10 4 g / mol, the molar fraction of vinyl is 0.55%), 10 mass shear thickening gel was added to the vacuum kneading m...

Technical field

[0001] The present invention relates to the technical field of foam materials, in particular to a silicone rubber foam material and a method of preparation thereof. Background

[0002] Compared with traditional impact-resistant materials, shear thickening materials have excellent damping properties and reversible soft-to-hard conversion characteristics. In its natural state, the shear thickening material maintains good flexibility and, when subjected to impact, it can quickly harden against impact.

[0003] Shear thickening materials can be divided into shear thickening gel and shear thickening liquid, of which the shear thickening gel has better structural stability and high and low temperature resistance. However, due to the strong cold flow characteristics of the shear thickening gel, it is impossible to maintain its original shape in its natural state. Therefore, in traditional techniques, porous materials are often used as a skeleton to coat the shear thicken...

Examples

preparation example Construction

[0023] The preparation method of the silicone rubber foam material provided in the present invention comprises the following steps:

[0024] S1, the polydimethylsiloxane, boric acid and its derivatives and organic solvents are formulated into a polydimethylsiloxane solution, and polycondensation reaction is carried out, and then the unreacted boric acid and its derivatives and the organic solvent are removed to give a shear thickening gel;

[0025] S2, the shear thickening gel of 1 mass part -10 mass parts is mixed with 100 mass parts of silicone rubber containing vinyl to obtain a silicone rubber binder;

[0026] S3, the silicone rubber binder with 1 mass part -20 mass nanocellulose, 1 mass part -10 mass parts of the expanded microspheres, 0.01 mass part -0.5 mass part of the organic peroxide crosslinker for mixing, to obtain silicone rubber compound; and

[0027] S4, the silicone rubber compound is pre-formed and cross-linked foamed to obtain a silicone rubber foam material.

[...

Embodiment 1

[0049] 10 mass parts of hydroxyl-terminated dimethicone (kinematic viscosity of 65cSt), 0.5 parts of dried boric acid, 89.5 parts of mass toluene were added to the sealed container in turn, stirred at a speed of 120 rpm at 60 °C for 120 min, to obtain a uniform hydroxyl end polydimethylsiloxane solution, and the hydroxyl end polydimethylsiloxane solution was heated to 120 °C for condensation reaction, and the reaction was 12h at a stirring speed of 120 rpm. Polyborosiloxane solution is obtained. Then, the polyborosiloxane solution was filtered out of the unreacted boric acid particles with a pore size of 0.44 μm, the filtrate was poured into a glass dish, and placed in a vacuum oven at 80 °C, -3 MPa to dry for 24 h, the toluene was removed, and the shear thickening gel was obtained.

[0050] 100 parts of methyl vinyl silicone rubber (hardness 40A, molecular weight of 50×10 4g / mol, the molar fraction of vinyl is 0.55%), 10 mass shear thickening gel was added to the vacuum kneadin...

Embodiment 2

[0054] 10 mass parts of hydroxyl-terminated dimethicone (kinematic viscosity of 75cSt), 0.5 parts of dried boric acid, 89.5 parts of mass toluene were added to the sealed container in turn, stirred at a speed of 120 rpm at 60 ° C for 120 min, to obtain a uniform hydroxyl-terminated dimethicone solution, and the hydroxyl end polydimethylsiloxane solution was heated to 120 ° C for condensation reaction, and reacted at a stirring speed of 120 rpm for 12 h. Polyborosiloxane solution is obtained. Then, the polyborosiloxane solution was filtered out of the unreacted boric acid particles with a pore size of 0.44 μm, the filtrate was poured into a glass dish, and placed in a vacuum oven at 80 °C, -3 MPa to dry for 24 h, the toluene was removed, and the shear thickening gel was obtained.

[0055] 100 parts of methyl vinyl silicone rubber (hardness 40A, molecular weight of 50×10 4 g / mol, the molar fraction of vinyl is 0.55%), 10 mass shear thickening gel was added to the vacuum kneading m...

Images