A kind of high-temperature-resistant mildew-proof silicone sealant and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant mildew-proof silicone sealant and a preparation method thereof. The high-temperature-resistant mildew-proof silicone sealant comprises the following components calculated in parts by weight: α,ω-dihydroxy polysiloxane 50 ~100 parts; 5~20 parts of reinforcing filler; 5~20 parts of methyl phenyl silicone oil; 40~100 parts of high temperature resistant filler; 0.05~0.2 parts of antifungal agent; 0.2-1 part of coupling agent; the α,ω-dihydroxypolysiloxane is α,ω-dihydroxypolydimethylsiloxane, α,ω-dihydroxypolydimethylsiloxane, phenyl substituted partial side chain methyl Mixture of dihydroxypolymethylphenylsiloxanes. The high-temperature resistant and mildew-resistant silicone sealant prepared by the invention has good elasticity, high tensile strength and elongation at break, and excellent high-temperature resistance and heat-and-humidity resistance.

Description

technical field [0001] The invention relates to the field of silicone sealant, in particular, the invention relates to a high-temperature-resistant and mildew-resistant silicone sealant and a preparation method thereof. Background technique [0002] Silicone sealant is made of hydroxyl-terminated polydimethylsiloxane as the main film-forming substance, supplemented with plasticizers, fillers, cross-linking agents, coupling agents and catalysts, and mixed under high-temperature dehydration and vacuum Its film-forming and curing mechanism is firstly that after the cross-linking agent in the system contacts the moisture in the atmosphere, the hydrolyzable functional group undergoes a hydrolysis reaction rapidly to form silanol. The Si-OH of its silanol undergoes a condensation crosslinking reaction with the Si-OH at both ends of the polydimethylsiloxane to form an elastomer with a three-dimensional network structure. Silicone sealants have excellent bonding properties, good el...

AI Technical Summary

Problems solved by technology

Although silicone sealants are widely used in modern industry and have broad market prospects, there are still many problems in the process of use, such as slow deep curing of one-component products, low tensile strength and elongation at break, poor storage stability, etc. series of questions

The silicone sealant products in the prior art have poor mildew resistance and heat resistance. For example, after curing, they cannot be placed in a high-humidity environment for a long time, and mold is easy to breed. In terms of heat resistance, it cannot withstand the working environment above 200°C for a long time, or the short-term temperature working environment below 300°C

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