FLUORESCENCE STUDIES ON MORPHOLOGICAL CHANGE OF ST/DVB CROSSLINKED GELS DURING CHLOROMETHYLATION

作     者：ZHANG Jixiang LI Hexian WANG Guochang WANG Lin WANG Ying HE Binglin 

作者机构：State Key Laboratory of Functional Polymer Materials For Adsorption and Separation and Institute of Polymer ChemistryNankai UniversityTianjin 300071China 

出 版 物：《Chinese Journal of Reactive Polymers》 (中国反应性高分子(英文版))

年 卷 期：2002年第11卷第2期

页      面：185-191页

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070305[理学-高分子化学与物理] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：National Natural Scientific Foundation of China (Project grant No.29574165 29928003 29874019) National Natural Scientific Foundation of Tianjin (Project grant No.013604011) 

主　　题：Crosslinked Polystyrene Chloromethylation Fluorescence Spectroscopy Hypercrosslinked Gels 

摘      要：The morphological change of St/DVB crosslinked gels during chloromethylation wasstudied by fluorescence spectroscopy using St/DVB crosslinked and hypercrosslinked gels as controlsamples. It has been found that with increase of chlorine content, the excimer emission band (~325nm)approaches to vanish, while the intensity of multi-ring aggregate emission band (~420nm) quicklyreaches a maximum, and then decreases sharply accompanied by appearance ofa new broad bandcentred at ca 488nm which roughly coincides with the typical emission band of hypercrossllinkedSt/DVB gels. Mearwhile, the result of IR measurement suggests that methylene bridge between phenylrings forms and increases with chloromethylation process. These results are explained in terms ofaside reaction of post-crosslinking, which densifies the loosely crosslinked networks and undoes thedensely entangled microgel nuclei. As a result, the morphology of the crosslinked gels becom es morehomogeneous with chloromethylation.