Silane coupling agent

Silane coupling agent is an organosilicon compound with active functional groups that can chemically bond with active groups in organic materials and hydrolyzable chlorine atoms or alkoxy groups. The common silane coupling agent is usually connected to the silicon atom with three hydrolyzable chlorine atoms or alkoxy groups and a carbon functional group that can react with organic compounds. For example, the carbon functional group is directly connected to a carbon atom on the silicon atom, which is called an alpha-carbon-functional silane coupling agent. If three carbon atoms are connected to silicon atoms, the silane coupling agent is called gamma position.

The most commonly used silane coupling agents have active functional groups such as amino group, epoxy group, acrylyexy group, sulfhydryl group, polysulfide group, vinyl group and so on.

Different kinds of silane coupling agents have different synthesis methods. In industrial production, the main technological routes of silane coupling agents most commonly used include two categories: chlorosilane method and silanol direct method. In the chlorosilane method, the silane coupling agent was synthesized by addition process, esterification process and group conversion process. In the direct method, various silane coupling agents are synthesized by adding alkoxy silane directly with silicon and alcohol as raw materials under the action of catalyst. Silane coupling agent is one of the most important organosilane compounds. Some silane coupling agents are often used as protectors of active groups such as hydroxyl groups in chemical synthesis, especially in the pharmaceutical industry.

Silane coupling agent in China

In the early 1960s, due to the rapid development of laminated materials (commonly known as fiberglass) used epoxy resin or unsaturated polyester resin and glass cloth to make dinghies and chemical storage tanks, it is urgent to solve the problem of dinghies falling apart and disintegrating due to the influence of moisture intrusion between organic resin and inorganic fiberglass. It was known that a complex of methacrylic acid and chromium called Volan could improve the hydrolytic stability of glass fiber and resin laminates, but it was also known that organic silicon monomers could play the same role.

1962 Beijing institute of chemical industry accepted the task of making vinyl trichlorosilane from trichlorosilane and vinyl chloride by thermal condensation. Vinyl chloride had to be bought in a polyvinyl chloride factory, while trichlorosilane was not. The synthesis of trichlorosilane involves the reaction of dry hydrogen chloride gas with silicon. And dry hydrogen chloride gas is not commercial, so the author and wu shengquan et al first in the laboratory with hydrochloric acid drop concentrated sulfuric acid method to produce hydrogen chloride gas drying after the synthesis of trichlorosilane. The effect of trace water in hydrogen chloride gas on yield was observed. After exploring and obtaining the reaction parameters, discuss with Beijing chemical industry co., LTD., which produces PVC, design a small fluidized bed by Beijing chemical research institute, and find a place in their factory to produce trichlorosilane with their dried hydrogen chloride. There was a great atmosphere of collaboration and they didn't bargain. Therefore, the small fluidized bed designed by Yang dahai, an engineer of Beijing research institute of chemical industry, and wu shengquan, etc., was manufactured in the research institute and moved to the second Beijing chemical industry plant, which has both hydrogen chloride and vinyl chloride. With the cooperation of the factory, it was successfully tested in 1963.

The trichlorosilane produced by Beijing no. 2 chemical plant provides the raw material for the synthesis of vinyl trichlorosilane by thermal shrinkage. The trichlorosilicon produced by this factory also provides raw materials for other units to develop organosilicon coupling agents. Especially, it provides the key raw material for nonferrous metallurgical system to study polysilicon.