Silane coupling agent reactions

Table Kinetic data of polymer/silane coupling agent reaction system.

Hydrosilylation. The addition reaction of silane of silane coupling agents. 

The addition—reaction product of bisphenol A [80-05-07] and glycidyl methacrylate [106-91-2] is a compromise between epoxy and methacrylate resins (245). This BSI—GMA resin polymerizes through a free-radical induced covalent bonding of methacrylate rather than the epoxide reaction of epoxy resins (246). Mineral fillers coated with a silane coupling agent, which bond the powdered inorganic fillers chemically to the resin matrix, are incorporated into BSI—GMA monomer diluted with other methacrylate monomers to make it less viscous (245). A second monomer commonly used to make composites is urethane dimethacrylate [69766-88-7]. 

The possible reaction between silane coupling agents and inorganic fillers are [66-69]... 

The silane coupling agents undergo chemical reaction with the surface of inorganic substances to form an SiOM bond (M Si atom in glass). 

The formation of these polar groups contributes increased adhesion. Observation of disappearing vinyl groups in the silane coupling agent and of the formation of polystyrene in the silica by FTIR analysis (Fig. 15) have confirmed the occurrence of a reaction between the polymer and the silane coupling agent [77]. 

A second industrially important field in which silanols play a vital role is in the preparation of polysiloxanes, often known as silicones. As in the case of silane coupling agents, there is a vast literature available on the topic of polysiloxanes, and only the most general discussion will be given here, concentrated on the reactions that involve silanols. 

Figure 13.10 The isocyanate-containing silane coupling agent can be used to couple hydroxyl-containing molecules to inorganic surfaces. The reactions should be done in dry organic solvent to prevent hydrolysis of the reactive group.

The reaction between MAH, PE, clay and the catalyst must take place essentially simultaneously. If the clay is first reacted with MAH at elevated temperatures, analogous to the treatment of clay with silane coupling agents, a clay maleate half ester or diester is probably formed. The latter does not readily react with PE even in the presence of a free radical catalyst. 

One conventional procedure for organic modification of inorganic particles is to utilize the reaction of the hydroxyl group with silane coupling agents. Many kinds... 

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