Preparation of double-chain polysiloxane by template polymerization and the coexistence of water repellency and adhesion to glass in its cast film

摘要

A soluble double-chain (ladder-like) polysiloxane (DC-PS) with high thermal stability was successfully prepared by intramolecular polycondensation (template polymerization) of a polysiloxane, in which diethoxysilyl groups were introduced into the side chains, using hydrochloric acid and purified water as the catalysts. The DC-PS cast film had coexistence of relatively high water repellency and adhesion to glass. In this study, soluble double-chain (ladder-like) polysiloxane (DC-PS) was successfully prepared by intramolecular polycondensation (template polymerization) of polysiloxane, in which diethoxysilyl groups were introduced into the side chains, using hydrochloric acid and purified water as the catalysts. Based on the solubility, gel permeation chromatography, IR, H-1 NMR, Si-29 NMR, and transmission electron microscopy (TEM) results, it was found that DC-PS has a structure in which two polysiloxane chains are connected in parallel by urea bonds, although it is slightly defective, as the cyclic trimer component and the silanol group are present. In addition, thermogravimetric analysis (TGA) confirmed that DC-PS showed high thermal stability. Furthermore, a DC-PS cast film had relatively high water repellency, adhesion to a glass substrate, and surface hardness.