The coupling agent can be generally classified into a silane coupling agent, a titanate coupling agent and other coupling agents according to a chemical structure. Generally, the functional groups at both ends of the coupling agent react with the dispersed phase of the filler and the matrix polymer, respectively. The coupling effect varies greatly depending on the filler. For example, the silane coupling agent has a remarkable effect on silica, alumina, glass fiber, clay, silicate, silicon carbide, etc., for talc, clay, hydrogen. Alumina, wollastonite, iron powder, alumina and other effects are slightly worse. The effects on asbestos, titanium dioxide and ferric oxide are not too great. The effects on calcium carbonate, graphite, carbon black, barium sulfate and calcium sulfate are very good. small. The filler with a silanol group on the surface has a large coupling effect of silane coupling agent, but the coupling effect of the silane coupling agent is not obvious for calcium, magnesium, barium carbonate, sulfate, sulfite, etc. . If the surface of the filler particles having no silanol groups is treated with a hydrosol of silica and then a silane coupling agent is used, a better coupling effect is produced. This treatment is called a two-coat method. Both the titanate coupling agent and the aluminate coupling agent can treat the surface of the filler, but the treatment effect has certain specificity. For example, the filler with better effect of titanate coupling agent is calcium carbonate, barium sulfate, calcium sulfate, calcium sulfite, aluminum hydroxide, magnesium hydroxide, calcium silicate, aluminum silicate, titanium dioxide, asbestos, alumina. ,Ferric oxide, Lead oxide, ferrite, etc.; the filler with a slight effect is mica, silica, magnesia, calcium oxide, etc.; the filler with poor treatment effect is talc, carbon black, wood powder; graphite with almost no effect , magnetic powder, clay, general pigments, etc. However, it should be determined according to the specific variety, grade and dosage of the coupling agent. Digital Tape Measure,Laser Measure Tapes,Laser Digital Measure Tape,Digital Display Laser Measure Tapes Shangqiu Hengli Measuring Tools Co.,Ltd , https://www.henglimtools.com
How to choose and apply a coupling agent as an important part of the auxiliary