As mentioned above, one of the main applications of Silane Coupling agent is the processing of inorganic fillers for organic polymers. The latter by Silane Coupling agent treatment, can turn its hydrophilic surface marry organic table surface, which can avoid particle buildup and sharp gelled polymer in the system, also can improve the wettability of organic polymer for reinforcing filler, through carbon functional Silane still can make reinforcing fillers and polymer solid bonding.
However, the effect of Silane Coupling agent is also related to the type and amount of Silane Coupling agent, the characteristics of the substrate, the properties of the resin or polymer, and the application occasions, methods and conditions. This section focuses on two applications of Silane Coupling agent, surface treatment and integral blending. The former method is to treat the surface of the substrate with Silane Coupling agent dilute solution. The latter method is to add Silane Coupling agent solution or solution directly into the mixture composed of polymers and fillers, which is especially applicable to the material system that needs to be stirred and mixed.
Silane Coupling agent consumption calculation
The number of reaction active points per unit specific surface area of the treated substrate and the thickness of Silane Coupling agent cover surface are key factors to determine the amount of Coupling agents required for siliconization of the substrate surface. In order to obtain monomolecular coating, the content of Si-OH in the matrix was determined. Known, most of the silicon substrate containing Si - OH is to 4-12 / mu ㎡, and uniform distribution, 1 molsilane Coupling agent can cover about 7500 m2 of the substrate. Silane Coupling agent with a plurality of hydrolyzable groups may affect the accuracy of calculation due to its own condensation reaction. If the matrix is treated with Y3SiX, a monomolecular layer coverage consistent with the calculated value can be obtained. However, because Y3SiX is high in price and poor hydrolysis resistance, it has no practical value. In addition, the number of Si-OH on the surface of the matrix also varies with the heating conditions.
Normal Si - OH, for example, the number is 5.3 per mu ㎡, siliceous substrates by under 400 ℃ or 800 ℃ after heat treatment, the Si - OH value can be correspondingly reduced to 2.6 / mu ㎡ or < 1 / mu ㎡. On the contrary, high Si-OH content can be obtained by treating matrix with hydrochloric acid. The surface of the substrate can be treated with alkaline detergent to form silicone alcohol shade