| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a cyclic oligosiloxane by which the gelatinization of a reaction system in the case or the like of carrying out a long term reaction under a condition of having a high catalyst content at high temperature, by reacting a polysiloxane in the presence of a metal alkoxide with an added specific additive. SOLUTION: (A) A linear or cyclic polysiloxane is heated in the presence of (B) a metal alkoxide in (C) an added at least one additive selected from an inert solvent, disiloxane or trisiloxanes, alcohols, a carboxylic acid ester or orthoesters of an alcohol each having >=140 deg.C boiling point to provide the objective practicably cyclic oligosiloxane. The component A is preferably a polysiloxane of formula I (R1 is a monovalent hydrocarbon; R2 is hydroxy group or the like; R3 is H or a monovalent hydrocarbon; R4 to R6 are each a monovalent hydrocarbon; k and l are each 0 or 1-1,000 with the proviso that they satisfy the equation 4<=m+n<=1,000) and/or formula II (m and n are each a number of 0 or 1-1,000 with the proviso that they satisfy the equation 4<=m+n<=1,000).
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