纤维素-甲基丙烯酸羟乙酯接枝共聚物的ATRP均相合成,结构和性能研究(英文)

Preparation,Characterization and Properties of Cellulose-g-PHEMA Copolymer by ATRP in Homogeneous Medium

在氯化锂/N,N-二甲基乙酰胺(LiCl/DMAc)体系中,利用2-溴代异丁酰溴与纤维素的直接酯化反应首先合成了具有不同引发点数量的ATRP大分子引发剂(cell-Br);然后以CuBr/PMDETA为催化体系,cell-Br为引发剂,将2-甲基丙烯酸羟乙酯通过原子转移自由基聚合ATRP法接枝到纤维素的大分子骨架上合成纤维素-甲基丙烯酸羟乙酯接枝共聚物(cellulose-g-PHEMA)。通过FT-IR,1H NMR,GPC和TGA对cell-Br和cellulose-g-PHEMA的结构和性能进行分析,并利用动态光散射(DLS),原子力显微镜(AFM),透射电镜(TEM)观察了cellulose-g-PHEMA的微观形貌,结果表明cellulose-g-PHEMA易于组装成直径约180 nm的球形胶束。

Cellulose-graft-poly （ 2-hydroxyethyl methacrylate ） （ cellulose-g-PHEMA ） copolymers were prepared by atom-transfer radical polymerization （ ATRP） . Cellulose macroinitiators with different numbers of initiating sites for ATRP were firstly synthesized by direct acylation of cellulose with 2-bromoisobutyryl bromide in LiCl/dimethylacetamide. Subsequently, ATRP of 2-hydroxyethyl methacrylate with cellulose macroinitiators was carried out using CuBr/PMDETA as a catalyst system. Formation of copolymers was confirmed by attenuated total reflectance Fourier transform infrared and GPC. The results of DLS, AFM and TEM also confirmed the synthesis of the grafted copolymer. It showed that the cellulose-g-PHEMA copolymers were easily to be self-assembled in water into spherical micelles with a radius of around 180 nm.