含偶氮苯液晶链段的ABC三嵌段共聚物的合成与表征

用原子转移自由基聚合方法通过两步聚合反应合成了一系列含偶氮苯侧链液晶链段的ABC三嵌段共聚物PEO-b-PMMA-b-PMMAZO.采用凝胶色谱(GPC)、傅立叶红外光谱(FT-IR)和核磁共振(1H NMR)等分析方法确定了产物的结构.以差示扫描量热仪(DSC)和偏光显微镜(POM)研究了ABC三嵌段共聚物PEO-b-PMMA-b-PMMAZO的热力学相转变行为,发现随着PMMAZO链段的质量百分比的增加,三嵌段共聚物中PMMAZO链段的TS-N和TN-I逐渐提高;同时,PMMA和PMMAZO链段的长短影响PEO链段的结晶性,随着液晶段PMMAZO和PMMA链段分子量的增加,PEO链段的结晶性减弱.

Synthesis and Characterization of ABC Triblock Copolymers with an Azobenzene Liquid Crystal Chain

A series of novel LC-coil ABC triblock copolymers with narrow polydispersities was synthesized by atom transfer radical polymerization(ATRP).Their structures were confirmed by Fourier Transform Infrared spectra(FT-IR),proton nuclear magnet resonance(1H NMR) and gel permeation chromatograph(GPC).Their thermotropic phase behavior was investigated by differential scanning calorimetry(DSC) and POM.It was found that TS-N and TN-I of PMMAZO was slightly increased with the increasieg of the mass ratio of liquid crystal block segments.PEO and PMMA block affected the liquid cystal behavior of PMMAZO. Meanwhile,PMMA and PMMAZO obviously influenced the crystals property of PEO segments,which was decreased as the increase of molecular weight of PMMA and PMMAZO segments.