Silane coupling agent is developed by United carbide company of USA, which is mainly used for glass fiber reinforced plastics. The molecular structure formula of silane coupling agent is generally y-r-si (or) 3 (where y-organic functional group, sior silyloxy group). Silyloxy groups are reactive to inorganic compounds, and organic functional groups are reactive or compatible with organic compounds. Therefore, when the silane coupling agent is between the inorganic and the organic interface, the organic matrix silane coupling agent inorganic matrix bonding layer can be formed. The typical silane coupling agents are A151 (vinyl triethoxysilane), A171 (vinyl trimethoxysilane), A172 (vinyltriethoxysilane), etc.
The use of silane coupling agents can be summarized into three aspects
It can improve the bonding function of glass fiber and resin, greatly improve the strength, electrical, water resistance, weather resistance and other functions of glass fiber reinforced composite materials. Even in wet state, it has a significant effect on the mechanical function of composite materials. Silane coupling agents have been widely used in glass fiber. The silane coupling agents used in this field account for about 50% of the total consumption. Among them, vinyl silane, aminosilane, methacryloyloxysilane and so on are widely used.
The surface treatment of the filler can be carried out in advance, or it can be directly added into the resin. It can improve the dispersion and adhesion of fillers in the resin, improve the compatibility between inorganic fillers and resins, improve the process function and improve the mechanical, electrical and weather resistance functions of filled plastics (including rubber).
Used as tackifier for sealants, adhesives and coatings
It can improve their adhesive strength, water resistance, weather resistance and other functions. Silane coupling agents are often able to deal with the problem that some materials cannot be bonded for a long time. The effect principle of silane coupling agent as tackifier is that it has two groups; one group can combine with the skeleton data to be adhered; the other group can combine with polymer materials or adhesives, thus forming a strong chemical bond at the bonding interface, which greatly improves the bonding strength. There are three ways to use silane coupling agent: first, as a surface treatment agent for skeleton data; second, adding it to adhesive; third, directly adding it to polymer data. From the perspective of giving full play to its effectiveness and reducing costs, the first two methods are better.
Author: coupling agent www.gbxfsilicones.com