Method for producing cyclic polysiloxane

A method for producing a cyclic polysiloxane, comprising the steps of:

• reacting a starting cyclic siloxane of general formula (1) below
• (wherein R1 and R2 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, and the subscript ‘a’ is an integer such that 3≤a≤5) with a dihalosilane of general formula (2) below
• (wherein R3 and R4 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group of 1 to 20 carbon atoms (exclusive of fluorine-containing monovalent hydrocarbon groups), and X is a halogen atom), accompanied by ring opening of the cyclic siloxane of general formula (1), in the presence of one or more catalyst selected from phosphorus compounds having a P═O bond with the exception of phosphoric triamides to obtain a linear polysiloxane capped at both ends of the molecular chain with halogen atoms;
• and
• reacting the resulting linear polysiloxane capped at both ends of the molecular chain with halogen atoms with water in a hydrolysis reaction in an alcohol solvent to obtain a cyclic polysiloxane of general formula (3) below
• (wherein R1 and R2 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, R3 and R4 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group of 1 to 20 carbon atoms (exclusive of fluorine-containing monovalent hydrocarbon groups), and the subscript ‘b’ is an integer such that 3≤b≤10).