I. Introduction to Silicone Rubber
Silicone rubber is the largest type of silicone products. It is an elemental organic elastomer obtained by hydrolysis and polycondensation of various dichlorosilanes. It can be divided into thermal vulcanization type (high temperature vulcanized silica gel HTV) and room temperature vulcanization type (RTV). The room temperature vulcanization type is divided into polycondensation reaction type and addition reaction type. High temperature silicone rubber is mainly used to make various silicone rubber products, while room temperature silicone rubber is mainly used as an adhesive, potting material or mold. Heat vulcanization type has the largest amount, heat vulcanization type is divided into methyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ, the largest amount and product brand), methyl vinyl phenyl silicone rubber PVMQ (low temperature resistance, radiation resistance ), Others are fluorosilicone rubber, etc.
1. Characteristics of silicone rubber
The molecular structure of organosilicon (polydimethylsiloxane) is dominated by siloxane bonds and the structure is very stable. Compared with ordinary organic rubbers, organosilicon compounds have many beneficial properties, such as heat resistance, electrical properties Insulation, chemical stability, etc.
Due to the helical structure of the silicone, the intermolecular forces are very small, so the silicone has good elasticity, elasticity, and cold resistance. In addition, since the methyl group located on the outside of the helical structure can rotate freely, the silicone can also exert many unique surface characteristics, such as water resistance and mold release.
2.Processing of silicone rubber
Mixing rubber is made by repeatedly adding silicon rubber raw rubber to a double-roll rubber mixer or a closed kneader by gradually adding white carbon black, silicone oil, and other additives. According to the different fillers and additives, the properties of the silica gel are also different.