The general formula of silane coupling agent can be expressed as Y - R - SiX3

X and Y are two kinds of reactive groups with different reaction characteristics. Among them, X is easy to form a firm bond (chemical or physical) with glass, clay, silicon dioxide, metal, metal oxide, etc. In inorganic materials; 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. That's where the name silane coupling agent comes from.

According to the number of hydrolyzable groups (i.e., X groups) attached to silicon atoms, silane coupling agents can be divided into three functional types and two functional types. In recent years, polymer-type silane coupling agents with functional groups as polymers have also appeared. In foreign countries, silane coupling agent production 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, a variety of names. Currently, union carbide (UCC) is the world's largest producer of silane coupling agents and has the largest variety.

2. Application of silane coupling agent

Silane coupling agent was first developed as a glass fiber treatment agent for glass fiber reinforced plastics. As the silane coupling agent improves the adhesion between glass fiber and resin, the mechanical properties of reinforced plastics are significantly improved. With the rapid development of composite materials, silane coupling agents develop rapidly in variety and yield. In recent years, the introduction of certain functional groups into some materials by silane coupling agents can improve the surface properties of materials, and obtain anti-static, anti-mildew, anti-odor, anti-coagulation and physiological inertia, which is the beginning of new USES of silane coupling agents. Because of the development of many important application fields, silane coupling agent has become an important branch of organosilicon.

The silane coupling agent is obtained by the addition of polychloric acid catalyzed by platinum chloroform (HSiCl3) and unsaturated alkenes with reactive groups through alcohol hydrolysis. In essence, silane coupling agent is a kind of silane with organic functional groups. In its molecules, it also has reaction groups that can chemically combine with inorganic materials (such as glass, silica sand, metal, etc.) and chemically combine with organic materials (synthetic resin, etc.). It can be represented by general formula Y (CH2) nSiX3, where n=0 ~ 3; X- hydrolyzable group; Y - an organic functional group that reacts with resins. X is usually chlorine group, methoxy group, ethoxy group, methoxy ethoxy group, acetyloxy group, etc., when these groups are hydrolyzed, they will form silicon alcohol (Si(OH)3), and combine with inorganic substances to form siloxane. Y is for vinyl, ammonia, epoxy, methacrylate, mercapto, or urea-group. These reaction groups may react with organic substances to bind.