光敏感遥爪聚合物——聚4-乙烯基吡啶的制备及其溶液性质

Synthesis and Solution Properties of the Photo-Sensitive Telechelic Polymer——Coumarin-Containing Poly(4-vinylpyridine)

以香豆素二硫化物(C-S-S-C)/三丁基膦(Bu3P)/H2O复合体系为链转移剂,偶氮二异丁腈(AIBN)为引发剂,4-乙烯基吡啶为单体制备了末端含有疏水性香豆素光响应基元的光敏感遥爪聚合物(聚4-乙烯基吡啶(C-P4VP)).用傅里叶变换红外(FTIR)光谱、凝胶渗透色谱(GPC)、氢核磁共振(1H-NMR)等对该聚合物进行了结构表征.研究显示该遥爪聚合物可在不同pH值(pH=3-6)的酸性水溶液中自组装成胶束,且随体系酸值的降低,聚合物胶束结构由松散变为紧密,同时香豆素端基的光二聚反应程度呈现先下降后上升的趋势.

A novel photo-sensitive telechelic polymer——coumarin-containing poly（4-vinylpyridine） （CP4VP） was prepared using 4-vinylpyridine as a monomer,azodiiso-butyronile （AIBN） as an initiator,and coumarin-containing disulfides （C-S-S-C） as a chain transfer agent in the presence of tributylphosphine （Bu3P）/H2O.The polymer was characterized by Fourier transform infrared （FTIR） spectroscopy,1H nuclear magnetic resonance （1H-NMR）,and gel permeation chromatography （GPC）.We found that the telechelic polymer can form polymer micelles in aqueous solutions at various pH values （pH=3-6）.Additionally,when lowering the acidity of the aqueous solution,the polymer micelles gradually compacted and the degree of coumarin photo-dimerization decreased initially and then increased within a similar irradiation time.