Study on radiation-induced grafting of styrene onto chitin and chitosan

Radiation-induced grafting of styrene onto chitin and chitosan powder was performed at room temperature. The effect of various conditions such as absorbed dose, solvent and oxygen on grafting was investigated. The grafting yield increased with the increase in absorbed dose. At the same dose, the grafting yield of styrene on chitosan was higher than that on chitin. The grafting reaction was promoted in the presence of methanol, and oxygen delayed the grafting reaction but did not inhibit it completely. In order to study the mechanism of grafting reaction and analyze the grafted samples, the grafted products were extracted first by benzene, then they were hydrolyzed in the presence of acid and separated by thin layer chromatography (TLC). Three different kinds of polystyrene (PS), i.e. PS grafted onto chitin, PS embedded in chitin and PS in grafting solution were gained. The variation of their molecular weight (MW) and width index of molecular weight distribution (M-W/M-n) determined by gel permeation chromatography (GPC) at different grafting conditions is discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.Chemistry, PhysicalNuclear Science & TechnologyPhysics, Atomic, Molecular & ChemicalSCI(E)EI7ARTICLE2149-1536