Synthesis of Regulated Structure Polyphonylether-Siloxane Block Copolymers

摘要

The substitution of diphenyldianilinosilane for dichlorosilane in the copolymerization with 4,4 -dihydroxydiphenylether has resulted in a copolymer with a molecular weight of at least 50,000.nThe Ullmann condensation is disappointing as a means of preparing dihydroxy derivatives of polyphenylethers. Side reactions reduce the yield. However, intermolecular dehydration of hydroquinone holds promise as a method of preparing 4,4-dihydroxydiphenylether and the dihydroxy derivatives of polyphenylethers.