The general formula of silane coupling agent can be expressed as: Y -- R -- SiX3, X and Y are two kinds of active groups with different reaction characteristics. Among them, X is easy to combine firmly with glass, clay, silica, metal and metal oxide in inorganic materials (chemical or physical); While Y easily with organic produce good combination of resin, rubber, etc (chemical or physical), at the same time, it is because of their molecules exist two functional groups of organic and inorganic, therefore, by silane coupling agent can organic material and inorganic material of these two kinds of nature difference is very big strong together (coupling), to obtain satisfactory adhesion. This is where the name silane coupling agent comes from. According to the number of hydrolyzable groups (that is, X groups) connected to silicon atoms, silane coupling agents can be divided into two categories: trifunctional type and difunctional type. In recent years, polymer silane coupling agents with polymer functional groups have emerged. In foreign countries, because the production of silane coupling agent is mainly controlled by several large companies, in order to form a monopoly, each brand. Therefore, the same product, the market can appear several brands, various names.