Bicomponent condensed type room temperature vulcanization silicon rubber

Abstract

The invention discloses a bicomponent condensed type room temperature vulcanization silicon rubber comprising the following components in parts by weight: 190-240 parts of component A and 8.5-16 parts of component B, wherein the component A is prepared by grinding the following raw materials in parts by weight through a three-roller grinder: 100 parts of hydroxyl-terminated polydimethylsiloxane, 30-40 parts of plasticizers and 60-100 parts fillers; and the component B is prepared by mixing the following raw materials in parts by weight under the protection of nitrogen: 5-10 parts of cross-linking agents, 3-5 parts of tackifiers and 0.5-1 parts of catalysts. The tackifier is an isocyanate hydrocarbyl silane coupling agent. The bicomponent condensed type room temperature vulcanization silicon rubber overcomes the defect of poor initial electric property the traditional bicomponent condensed type room temperature vulcanization silicon rubber system by adopting an isocyanate alkylsilane coupling agent and achieves the effect of fine initial electric property, high ageing resistance and good bonding property, thereby meeting the requirements for fast encapsulation and use of electrons.

Description

technical field [0001] The invention relates to a silicone rubber used for potting protection of electronic products, in particular to a two-component condensation type room temperature vulcanized silicone rubber. Background technique [0002] With the rapid development of my country's industrial electronics industry, more and more electronic components are used, and the degree of integration is getting higher and higher. Electronic components are exposed to the environment and are susceptible to interference from moisture, dust, salt spray and other media, which reduces the reliability and life of electronic components. Therefore, the protection of components has become a problem that must be solved. There are three main chemical types of electronic adhesives currently used to protect electronic components: epoxy resin adhesives, polyurethane adhesives, and silicone rubbers. Epoxy resin glue has good electrical properties, but due to the high hardness and strength of epox...

AI Technical Summary

Problems solved by technology

Addition-type potting silicone rubber has good electrical properties, low shrinkage after curing, and good anti-aging performance, but there are two disadvantages of addition-type two-component potting silicone rubber. The adhesion is extremely poor; easily affected by organic nitrogen, sulfur, phosphorus and other compounds, resulting in catalyst poisoning and local non-curing problems

However, there is a big problem with the condensation-type two-component silicone rubber potting glue: because the glue will release alcohol substances after curing, the electrical performance of the initial stage after curing is poor. According to the different potting thickness, some even have three It takes months to achieve the stability of electrical performance, which leads to the failure to check the accuracy of electrical signals in many occasions. At the same time, there will be protection failures and even circuit burnouts during the initial working process of components.

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