Hua Daoben, Deng Weicai, Tang Jing, Cheng Jianxin, Zhu Xiulin
Key Laboratory of Organic Synthesis of Jiangsu Province, School of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215123, PR China.
Int J Biol Macromol. 2008 Jul 1;43(1):43-7. doi: 10.1016/j.ijbiomac.2007.12.009. Epub 2008 Jan 9.
The controlled graft modification of chitosan has first been achieved by nitroxide-mediated polymerization using chitosan-TEMPO macroinitiator. Chitosan-TEMPO macroinitiator was obtained from the (60)Co gamma-ray irradiation of N-phthaloylchitosan and 4-hydroxy-TEMPO in DMF under argon atmosphere. The graft copolymers were characterized by (1)H nuclear magnetic resonance ((1)H NMR), Fourier transform infrared spectrometer (FT-IR), X-ray powder diffractometer (XRD) and high performance particle sizer (HPPS). The results indicate that the graft copolymers were successfully synthesized and that the graft polymerization was well controlled by the nitroxide-mediated process. The size distribution of chitosan-g-polystyrene in benzene is very narrow, which may be associated with the "well-defined" polystyrene (PSt) onto chitosan from nitroxide-mediated polymerization. This work provides a new method to prepare chitosan grafting copolymers with controlled molecular weights and "well-defined" structures.
壳聚糖的可控接枝改性首先通过使用壳聚糖-TEMPO大分子引发剂的氮氧自由基介导聚合反应得以实现。壳聚糖-TEMPO大分子引发剂是在氩气氛围下，由N-邻苯二甲酰壳聚糖和4-羟基-TEMPO在N,N-二甲基甲酰胺中经（60）Coγ射线辐照获得的。通过氢核磁共振（1H NMR）、傅里叶变换红外光谱仪（FT-IR）、X射线粉末衍射仪（XRD）和高性能粒度分析仪（HPPS）对接枝共聚物进行了表征。结果表明，接枝共聚物已成功合成，且接枝聚合反应通过氮氧自由基介导过程得到了良好控制。壳聚糖-g-聚苯乙烯在苯中的尺寸分布非常窄，这可能与氮氧自由基介导聚合反应中壳聚糖上“结构明确”的聚苯乙烯（PSt）有关。这项工作为制备具有可控分子量和“结构明确”结构的壳聚糖接枝共聚物提供了一种新方法。
