General Principles For Selecting Silane Coupling Agent

- Jul 10, 2018-

It is known that the hydrolysis rate of Silane Coupling agent is si-x of the silicon energy group, and the reaction activity of the Silane Coupling agent with the organic polymer is c-y of the carbon functional group. Therefore, for different substrates or processing objects, it is essential to select the applicable Silane Coupling agent. The method of selection is mainly preselected by experiments and should be carried out on the basis of existing experience or law. 

For example, in general, unsaturated polyester mostly USES Silane Coupling agent containing CH2=CMeCOO, Vi and CH2-CHOCH2O-. Most epoxy resins contain ch2-chchch2o and h2n-silane Coupling agents. Most phenolic resins contain H2N- and h2nconh-silane Coupling agents. Polyolefin is mostly vinyl silane. Sulfur - yellow vulcanized rubber is mostly alkyl silane. Due to the influence of a series of factors, such as wetting, surface energy, interface layer and polar adsorption, action of acid and alkali, interpenetrating network and covalent bond reaction, the adhesion between heterogeneous materials is affected. Therefore, the test preselection alone is sometimes not accurate enough, and the composition of the material and its sensitivity to the Silane Coupling agent should be considered comprehensively. 

In order to improve the stability of hydrolysis and reduce the cost of modification, Silane Coupling agent can be mixed with trialkylsilane. For refractory materials, the Silane Coupling agent can also be used as a cross-coupling polymer.

Silane Coupling agent, when used as a viscosifier, mainly generates chemical bonds and hydrogen bonds with polymers. Wetting and surface energy effects; It can improve the crystallinity, acid - base reaction and the formation of interpenetrating polymer network. 

Adhesion enhancement mainly consists of three systems: (1) inorganic materials to organic materials; (2) inorganic materials to inorganic materials; (3) organic materials to organic materials. For the first kind of adhesion, it is usually required to attach inorganic materials to polymers, so the reaction activity of Y and the functional groups contained in Silane Coupling agent should be given priority. The latter two are adhesion between the same type of materials, so Silane Coupling agent's own antihydrophilic polymer and Silane Coupling agent are selected when the inorganic materials require adhesion.