Low viscosity sealant-HongYe silicone

At present, the domestic electronics industry's largest amount is mainly ketoxime type silicone sealant, but because of its curing prolapse of the byproducts have peculiar smell, on the metal copper and polycarbonate plastic has certain corrosion, application was very limited. Dealcoholization type sealant after curing prolapse product because of its neutral alcohols, metal and plastic is not corrosive, more and more get industry attention. Early into the market dealcoholization type sealant mainly using aminosilane or organic tin catalyst exists, smells great, yellow. In recent 10 years in developed countries gradually by the titanate complexes as catalysts, its excellent adhesion, harmless to humans and the environment, has become a high-end electronic the mainstream industry products. Low viscosity sealant basic formula and preparation technology of: The first alkoxy-terminated polyorgano-siloxane viscosity is 1000 mPa• s 100, two dimethyl silicone oil 10, fumed silica 1~4, pigments are respectively metered in stirred tank, under the condition of vacuum dehydration 1 h high temperature, cooling to room temperature; according to the measurement of 3~8, adding cross-linking agent adhesion promoter, Mpa, the elongation at break increased from 80% to 145%. Description of silica-reinforced catalyst vacuum mixing 30 min, then under the protection of nitrogen in dry filtration, filling in tube. The sealant properties are as follows: 1) the white carbon black to the sealant has better reinforcement effect, small particle size, large specific surface area of silica reinforced effect is good, but on the properties of viscosity and adverse effects. 2) the level of silica increased, although the sealant mechanical properties are increased but the viscosity will increase linearly, the dosage is 1~2 a good. 3) using trimethoxy silane as crosslinking agent can obtain fast surface dry speed, at the same time the depth of curing sealant performance is good; the amount of crosslinking agent in 6, the sealant can get better comprehensive performance. 4) using a patented amino silane enables the sealant to obtain better storage.