PREPARATION OF CYCLOPOLYDIORGANOSILOXANES VIA VAPOR PHASE REARRANGEMENT

摘要

PREPARATION OF CYCLOPOLYDIORGANOSILOXANES VIA VAPOR PHASE REARRANGEMENT A process for preparing a product cyclopolydiorganosiloxane, (R2SiO)c. The process comprises (A) vaporizing a feed cyclopolydiorganosiloxane material, (R2SiO)x; (B) passing the vapors from (A) through a heated bed of a solid catalyst, the catalyst comprising an alkali metal compound; (C) controlling pressure and temperature in the heated catalyst bed to favor formation of (R2SiO)c in an equilibrating mixture with other cyclopolydiorganosiloxanes; and (D) recovering an amount of the product cyclopolydiorganosiloxane, (R2SiO)c, which is substantially increased from the amount present in the feed cyclopolydiorganosiloxane material.