本研究以幾丁聚醣為材料，以最佳溶劑－甲酸為溶劑，進行均相的化學反應修飾，利用馬來酸酐與幾丁聚醣的胺基反應，控制酸酐的比例及反應時間以獲得不同取代度的產物，讓具有生醫應用價值的胺基不至於完全反應，亦使幾丁聚醣上帶有馬來酸酐的雙鍵，將來可作進一步的高分子接枝。針對產物作結構分析，結果顯示於室溫反應下，幾丁聚醣確實與馬來酸酐有化學反應，且隨著酸酐量的增加而有轉化率增加的趨勢；另外轉化率也隨反應時間的增加而增加，在六小時左右達到平衡值。另外由於反應後產物共同擁有胺基及羧基，且為一親水性高分子，可藉由控制反應量的不同，令其擁有不同比例的胺基及羧基，在不同的pH 值下其膨潤比亦大幅的變化，為一pH敏感型高分子水膠。 In this study, chitosan was modified with maleic anhydride in formic acid through the reaction of amino group with anhydride group. In order to obtain products with different degree of substitution, different amount of maleic anhydride was employed to react with chitosan. After reaction, the available double bonds in the attached maleic acid can be further used for grafting synthetic polymers onto chitosan chains. The result showed that the degree of substitution increased with the added amount of maleic anhydeide. In addition, the conversion increased with reaction time and reached a plateau value after 6h. Because the products have amino group and carboxyl group, they have different swelling ratio values in different pH environments. It was confirmed as a pH sensitive hydrogel.
