新型支化侧链偶氮聚电解质的合成与性能研究

通过后重氮偶合的方法合成了一种含支化侧链偶氮苯生色团的聚电解质 (PBANT AC) .用IR、NMR、DSC、UV和元素分析等手段对聚合物的结构和性能进行了表征 .研究发现 ,在不同比例的水和四氢呋喃混合溶剂中PBANT AC的紫外 可见光光谱有很大的差别 .这种差别反映了PBANT AC分子中的偶氮苯生色团的不同聚集状态 .通过静电吸附逐层自组装的方法将PBANT AC分子组装成多层膜 .在 488nm的偏振Ar+ 激光的照射下 ,聚合物薄膜中的偶氮苯生色团可发生光致取向 ,取向有序度约 0 0 5 .偶氮苯生色团的顺反异构化反应使H 聚集体在光照后发生解聚集

SYNTHESIS,LAYER-BY-LAYER SELF-ASSEMBLY AND OPTICALLY INDUCED BIREFRINGENCE OF A NOVEL BRANCHED SIDE-CHAIN AZO POLYELECTROLYTE

A novel polyelectrolyte (PBANT-AC) functionalized with branched electron donating-accepting azobenzene chromophores has been synthesized through post-polymerization azo coupling reaction and characterized by 1H-NMR,FTIR and UV-Vis spectrometry.The degree of functionalization (DF) of PBANT-AC was 17% measured by elemental analysis.The degree of polymerization and its distribution were determined by GPC to be X n=588 with a polydispersion index 1 3.A glass transition temperature of 139℃ was observed from DSC thermogram.H-Aggregation of azo chromophores of PBANT-AC in H 2O-THF mixed solvent was detected from UV-Vis spectra and controlled by the ratio of V THF/V H 2O.The H-aggregates in water-tetrahydrofuran mixture were successfully fabricated into self-assembled multilayers with poly(diallydimethylammonium cloride) by an electrostatic layer-by-layer process.Birefringence and dichroism were optically induced in the self-assembled films under the irradiation of a polarized Ar + laser beam at 488 nm.The resulting dichroism was easily detected from UV-Vis spectra and exhibited long-term stability.The orientational order parameter obtained was 0 05 for the film.Upon irradiation,the H-aggregates of azo chromophores were changed to `isolated' form after the cis-trans isomerization.