Patent ID: 7678871

Claim:
A method for preparing a cyclic oligosiloxane, comprising reacting an organopolysiloxane having formula (1): wherein each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, and n is an integer of 20 to 10,000, in the presence of a catalyst, the cyclic oligosiloxane prepared having formula (3): wherein each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, and k is an integer of 3 to 8, wherein said catalyst has the formula (4): wherein each R 4 is independently a substituted or unsubstituted monovalent hydrocarbon group or a group of the formula (5): wherein each R 5 is independently a substituted or unsubstituted monovalent hydrocarbon group and h is an integer of 0 to 100, whereby the cyclic oligosilxane is produced without forming impurities having a silicon-alkoxide bond.