Synthesis of Triethoxysilyl-Terminated Polyoxazolines and Their Cohydrolysis Polymerization with Tetraethoxysilane

Polyoxazoline having a terminal triethoxysilyl group was successfully synthesized by the ring-opening polymerization of 2-methyl-2-oxazoline followed by termination with (3-aminopropyl)triethoiysilane. Triethoxysilyl-terminated telechelic polyoxazoline was prepared by using a bifunctional initiator. Furthermore, polyoxazolines having two or three triethoxysilyl groups were prepared by using diallylamine as a terminator followed by a hydrosilation reaction with triethoxysilane. These triethoxysilyl-terminated polyoxazolines were subjected to acid-catalyzed cohydrolysis polymerization with tetraethoxysilane by the so-called sol-gel method to produce a novel organic-inorganic polymer hybrid, which was a homogeneous transparent glassy composite material. The obtained hybrid showed a higher hydrophilic property in comparison with that of silica gel without polyoxazoline segments.