新型两亲性含糖嵌段聚合物的合成与自组装

Synthesis and Self-assembly Behavior of a Novel Amphiphilic Block Glycopolymer

以β-环糊精(β-CD)和2-乙基-2-噁唑啉(EtOz)为原料,通过活性端基化学偶联法制备了乙酰麦芽七糖/聚(2-乙基-2-噁唑啉)两嵌段聚合物(AcMH-b-PEtOz),借助核磁共振氢谱、红外光谱和凝胶渗透色谱等手段证实了产物的化学结构.采用核磁共振氢谱、荧光光谱、透射电子显微镜、动态光散射及紫外-可见分光光度等方法探讨了产物在水溶液中的自组装行为.结果表明,所得嵌段聚合物直接溶于水后可通过自组装形成纳米球形"核-壳"结构胶束,同时具有温度响应性.所得聚合物的临界胶束浓度(cmc)为4～7mg/L,平均粒径(d)为83～115nm,临界相转变温度(LCST)为49～64℃,并且均可通过PEtOz的链长进行调控.

A novel amphiphilic block polymers based on peracetylated maltoheptaose and poly（2-ethyl-2-oxazoline）（AcMH-b-PEtOz） was synthesized by endcapping reaction.Their structures were confirmed by the combined analyses from hydrogen nuclear magnetic resonance（1H NMR）,gel permeation chromatograph（GPC） and Fourier transform infrared spectrometry（FTIR）.Their micellar formation and characteristics in an aqueous phase were investigated by means of ^1H NMR,fluorescence spectrum,transmission electron microscopy（TEM）,dynamic light scattering（DLS） and UV-Visible spectrum.It was found that the obtained block polymers could self-assemble into nanosize spherical micelles with a core-shell structure in aqueous solution triggered by its amphiphilic character without any organic solvent and exhibited thermal sensitivity.The critical micelle concentration（cmc） of the micelles ranged from 4 to 7 mg/L with mean diameters in the range of 83—115 nm and lower critical solution temperatures（LCST） in the range of 49—64 ℃.The cmc,size and thermal sensitivity of the self-assembled micelles could be tailored by changing the PEtOz content of the resultant block polymer.