A new method of controlled grafting modification of chitosan via nitroxide-mediated polymerization using
Daoben Hua1, Weicai Deng, Jing Tang
1Key Laboratory of Organic Synthesis of Jiangsu Province, School of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215123, PR China. dbhua_lab@suda.edu.cn
Abstract:
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.
Related Concept Videos
Anionic Chain-Growth Polymerization: Overview
Ziegler–Natta Chain-Growth Polymerization: Overview
Anionic Chain-Growth Polymerization: Mechanism
Cationic Chain-Growth Polymerization: Mechanism
Radical Chain-Growth Polymerization: Overview
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...


