Commercial silanes, thermal stability

Several modifications of commercial silane coupling agents have been evaluated to search for improved bonding at the interface. These approaches attempt to use modifiers to counteract basic faults of the individual silanes. Some of these modifications include increased hydrophobic character, increased crosslinking of the siloxane structure, increased thermal stability, and ionomer bond formation to reduce shear degradation at the interface. 

The thermal stability of several commercial silanes was studied by determining isothermal weight loss of the hydrolyzed silsequioxane form of the silanes (RSiOj ) at 300°C [11]. Fig. 25.5 shows that the phenylsilyl structure has very good thermal stability, but that the diaminosilane has poorer thermal stability. The vinylbenzylaminosilane has surprising good thermal stability. Phenyltrimethoxysilane blends or vinylbenzylaminosilane have been recommended for high-temperature applications. 

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