Synthesis and Pyrolysis of Soluble Cyclic Hf-Schiff Base Polymers  

作　　者：Yu-Huan Wu Li Ye Ya-Nan Sun Wei-Jian Han Tong Zhao 

机构地区：[1]Key Laboratory of Science and Technology on High-tech Polymer Materials,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China [2]University ofChinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Journal of Polymer Science》2021年第6期659-664,I0005,共7页高分子科学（英文版）

基　　金：by the National Natural Science Foundation of China(No.21604090)。

摘　　要：Soluble Hf-containing polymers are significant processable precursors for the fabrication of ultra-high temperature ceramics.In this work,cyclic Hf-Schiff base polymers were synthesized via direct polymerization of hafnium alkoxide and bis-salen monomers.The defined structure and molecular weight of the polymers were characterized by NMR spectroscopy,gel permeation chromatography and MALDI-TOF mass spectroscopy.The feed ratio of monomers regulated the molecular weight and solubility of the polymers.This synthetic strategy features simple operation under ambient conditions,efficient reaction with high yield and cyclic polymers as the main products.The Hf-Schiff base polymers were converted to HfC/C materials after pyrolysis under argon at 1600°C,which was identified by XRD measurements,elemental analyses and Raman spectroscopy.This work will inspire more precise and efficient synthesis and applications of metallopolymers.

关 键 词：Hf-containing polymer Schiff base Cyclic polymer Preceramic polymer Hafnium carbide 

分 类 号：TQ317[化学工程—高聚物工业]