A kind of transparent high temperature resistant flame retardant silicone sealant and its preparation method

Abstract

The invention discloses a transparent high-temperature-resisting flame-retarding silicone sealant and a preparation method. The transparent high-temperature-resisting flame-retarding silicone sealantis characterized by being prepared from the following main components: room-temperature vulcanized methyl silicone rubber, vinyl phenyl silicon resin containing an epoxy group, a plasticizer, a heat-resisting additive, a flame retardant, a yellowing-resisting mildew preventive, a silane cross-linking agent, a silane coupling agent and a catalyst. The transparent high-temperature-resisting flame-retarding silicone sealant disclosed by the invention has the advantages that 1, the vinyl phenyl silicon resin containing the epoxy group is selected; after the resin is cured with the cross-linking agent, the resin has excellent high temperature resistance, cohesiveness, high light transparency and high reflectivity; high-heat-resisting additives including gas-phase SiO2, glass powder, ZnO and thelike are matched and added so that a product has higher high-temperature resistance and reinforcing performance; 2, the silicone rubber is compounded with an organic silicon modified phosphorus flameretardant so that the product has the advantages of good compatibility, light transparency, thermal stability, no volatile matters, no corrosive gas, lasting flame-retarding effect and the like; 3, the transparent high-temperature-resisting flame-retarding silicone sealant is mainly applied to manufacturing of high-power and high-reflection LED (Light Emitting Diode) screens and binding and sealing and the like of industries including photoelectric, electronic, artwork industries and the like.

Description

technical field [0001] The invention relates to the field of application of silicone sealants, in particular to a transparent high-temperature-resistant and flame-retardant silicone sealant for manufacturing high-power and high-refraction LED screens, optoelectronics, electronics and microelectronics, electric heating equipment, handicrafts and other fields. its preparation method. [0002] technical background [0003] Silicone sealants belong to silicone products. The main chain of the polymer is mainly composed of silicon-oxygen-silicon bonds. It is characterized by excellent high and low temperature resistance and weather resistance, strong adhesion, weather resistance, UV resistance, water resistance and moisture resistance; it is widely used in construction, electronic appliances, automobiles, aerospace and aerospace fields; as people With the increasing awareness of environmental protection and safety, the requirements for the fire protection level and environmental p...

AI Technical Summary

Problems solved by technology

[0003] Silicone sealants belong to silicone products. The main chain of the polymer is mainly composed of silicon-oxygen-silicon bonds. It is characterized by excellent high and low temperature resistance and weather resistance, strong adhesion, weather resistance, UV resistance, water resistance and moisture resistance; it is widely used in construction, electronic appliances, automobiles, aerospace and aerospace fields; as people With the increasing awareness of environmental protection and safety, the requirements for the fire protection level and environmental pollution of silicone sealants are getting higher and higher. At the same time, the pursuit of products not only must meet the conditions of use, but also the pursuit of aesthetics after use High; Ordinary transparent silicone sealants can generally maintain elasticity in the range of 120~200°C, and have little effect on mechanical properties and bonding properties, but they cannot be used for a long time in an environment above 250°C, and are prone to burning and yellowing ; Especially in the manufacture of high-power and high-refraction LED screens, applications in optoelectronics, electronics and microelectronics industries, etc., silicone sealants are required not only to have high temperature resistance, radiation resistance, flame retardant, ultraviolet resistance and other characteristics, but also have high High light transmittance and high refractive properties, etc. In recent years, there have been many studies on high temperature resistance and flame retardancy of silicone sealants, but most of them have added a large amount of AI(OH) 3 , Mg(OH) 2 、 Flame retardants such as fillers such as melamine cyanurate make the product opaque, especially in LED screens, optoelectronics, electronics and microelectronics industries, and handicrafts and other industries are greatly restricted

[0004] There are a lot of openly researched technologies about silicone sealants; both CN97107706.1 and CN200810227906.1 provide a room-temperature silicone rubber formula with flame retardancy, and the flame retardancy grade reaches UL94V-0 level, because of the addition of large melamine cyanurate Make the product into an opaque colloid, and decabromodiphenyl ether and the like are materials prohibited by EU standards; CN200510020702.7 discloses a kind of flame-retardant silicone structural sealant and its manufacturing method, but this patent formula adds A large amount of active calcium carbonate, the temperature resistance is generally around 200°C, and the addition of too much calcium carbonate makes the product an opaque colloid; 201610963294.7 discloses a neutral alcohol-type transparent silicone sealant and its preparation method , which mainly solves the problem of corrosiveness in the bonding of copper metals, mercury mirrors, and various electronic components using ketoxime-type sealants in the prior art, but no research has been done on the flame retardancy and high temperature resistance of the products; 201010557084.0 discloses a high-performance acidic transparent silicone structural sealant, provides a high-performance acidic structural sealant, fills the vacancy that neutral transparent silicone sealants cannot be used in glass fish tanks, and produces good adhesion to the substrate Adhesiveness, no whitening, no yellowing, no pollution to the environment

[0005] The above-mentioned patents are aimed at the research of different silicone sealant product systems, and propose different solutions for high temperature resistance, flame retardancy, adhesion and other properties, but for the high temperature resistance, flame retardancy, and resistance of transparent silicone sealant products Yellowing and anti-mildew performance did not propose a solution

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