Synthesis method of methylhydro cyclo siloxane

Abstract

A process for synthesizing methyl hydrocyclosiloxane, especially tetramethyl cyclotetrasiloxane (D4H) includes such steps as proportionally mixing silanes with paraffins, dropping it to multi-phase solvent mixture while stirring, and hydrolytic reaction at 0-30 deg.c for 2-8 hr. Its advantages are high output rate, and no pollution and by-product.

Description

Technical field [0001] The invention relates to a preparation method of methyl hydrogen cyclosiloxane, in particular to tetramethyl cyclotetrasiloxane (abbreviated as D 4 H ) Preparation method of methylhydrocyclosiloxane with high yield. Background technique [0002] Methyl hydrogen cyclosiloxane is generally composed of methyl dichlorosilane (M 1 H) It is obtained by hydrolysis to generate mixed ring bodies and linear bodies of various molecular weights. Sauer et al. published a paper in J.Am.Chem.Soc.Vol.68.962 in 1946, and pointed out that using diethyl ether and crushed ice as solvents, methyldichlorosilane was hydrolyzed to prepare methylhydrocyclosiloxane (HMCS), The total yield of the ring body is 56.7%, and the remaining linear body is 43.3%. In USP 3,484,468, Curry et al. introduced the hydrolysis of M in tertiary alcohol and benzene. 1 H, the total yield of the ring body is up to 66%, and the linear body is 34%; in USP3763212, EcEnee et al. believe that hydrolysis in ...

AI Technical Summary

Problems solved by technology

However, in this method, the amount of methanol, which is the most harmful to the human body, is as high as 50%, which constitutes a relatively large unsafe factor for production, life, and social environment.