Published: June 1983
Silicones, which are broadly classified as fluids, elastomers, and resins, are an extensive variety of polymers based on chains or networks of alternating silicon and oxygen atoms.
Silane monomers are the precursors of silicone polymers. More specifically, organohalosilanes are the backbone of the whole organo- silicon chemistry. The Si-O chains (siloxane chains) are almost invariably prepared by hydrolysis of organohalosilanes and condensation of the resulting organohydroxysilanes. Most of the silicone polymers are polymethylsiloxanes obtained from methylchlorosilanes. The properties of the polymer are greatly varied to obtain desired effects by incorporation of other groups such as phenyl, vinyl, chlorinated phenyl, cyano-alkyl, and fluoroalkyl.
This report includes evaluation of the processes for production of both the organohalosilane monomers and the silicone polymers. The organohalosilane monomers included are methylchlorosilanes, phenylchlorosilanes, and vinylchlorosilanes. The process for direct synthesis of trichlorosilane is also evaluated, as trichlorosilane is a starting material for some of the organohalosilanes.
The number of silicone polymers made commercially is very large. This report discusses the technology of producing silicone fluids, silicone elastomers (both heat curing and room temperature vulcanizing), and silicone resins. The economics of production of silicone fluids and elastomers are included.