Abstract: Hydroxyethylcellulose-g-poly(4-vinylpyridine) (HEC-g-P4VP) was synthesized by using ceric ammonium nitrate (CAN) initiator in aqueous nitric acid solution. The products were illustrated by FTIR and 1H NMR. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to study the micellization of copolymer in water. The pH-induced micellization of HEC-g-P4VP in water has been found. It showed that the morphology of micelles showed different solid and sphere structures at different pHs. Surface tension measurements were also studied by a set of drop volume techniques. With the grafting rate increasing，the surface tension tended to decrease.

Key words: hydroxyethyl cellulose, graft copolymer, 4-vinylpyridine, transmission electron microscopy

摘要： 采用硝酸铈铵（CAN，Ce4+）自由基引发聚合合成了羟乙基纤维素接枝聚4-乙烯基吡啶（HEC-g-P4VP）聚合物。并用FTIR、1H NMR确证了共聚物结构。将这种纤维素接枝改性聚合物溶解在不同pH值的水溶液中，研究了它的胶束化行为。利用扫描电镜（SEM）和透射电镜（TEM）相结合，对胶束化行为进行了观察，结果表明HEC-g-P4VP能够形成清晰的核壳结构。在不同pH值条件下，所形成的核壳结构有所变化。说明HEC-g-P4VP在溶液中具有一定的pH值诱导胶束化行为。最后，采用滴体积法对HEC-g-P4VP在水溶液中的表面张力进行了研究，随着接枝率的提高，其表面张力有降低的趋势。

关键词: 羟乙基纤维素, 接枝共聚物, 4-乙烯基吡啶, 透射电镜