Syntheses of High Molecular Weight Polysilazanes by the Ammonolysis of N,N-Diethylaminosilanes†
Yoshimoto ABE*, Koji YODA, Yoshiaki KUDO, Sumiyuki MURAYAMA and Takahiro GUNJI
Department of Pure and Applied Chemistry, Faculty Science and Technology, Tokyo University of Science; 2641 Yamazaki, Noda-shi 278-8510 Japan
Polysilazanes HPZ1 and HPZ2 were synthesized by the ammonolysis of chloro (N,N-diethylamino) sil-ane and bis (N,N-diethylamino) silane, respectively. Hydropolysilazanes, which were mainly composed of [H2Si (NH)] units with a molecular weight of 1000 (Mw) were unstable for self-condensation reaction in tetrahydrofuran (THF) solvent. The self-condensation of HPZ1 and HPZ2 was retarded by silylation of terminal groups with chloro (trimethyl) silane or by dilution with the solvent such as THF and ether. On the other hand, soluble hydropolysilazanes with very high molecular weight (Mw of 85000 (HPZ1) and 45000 (HPZ2)) were produced by aging 35 wt% and 45 wt% THF solutions of polysilazanes at 20 °C, respectively.
† Syntheses and Properties of Polysilazanes as a Precursor for Silicon Nitride. Part 3.
[Contents (In Japanese) ]
[Contents (In English) ]