This invention provides a graft copolymer hydrogel and a preparation method thereof and particularly relates to a material containing chitosan, lactic acid/glycolic acid and polyethylene glycol, which are combined through grafting and copolymerization to form an amphiphatic temperature-sensitive hydrogel. The preparation method for the graft copolymer comprises dissolving chitosan and polyethylene glycol in an aqueous solution of lactic acid/glycolic acid to perform polycondensation and obtain chitosan-grafted poly(lactic acid/glycolic acid) copolymer, poly(lactic acid/glycolic acid) and polyethylene glycol copolymer and a combination thereof alternatively, the chitosan-grafted poly(lactic acid/glycolic acid) copolymer is synthesized first and then polymerized with polyethylene glycol to form chitosan-poly(lactic acid/glycolic acid)-polyethylene glycol copolymer, which has temperature sensitivity and anti-bacterial property.本發明提供一種接枝共聚物水凝膠及其製備方法,特別是關於一幾丁聚醣、乳酸/甘醇酸與聚乙二醇材料,藉由接枝與共聚合反應進行複合,以形成一親疏水兩性之溫感性水凝膠。上述接枝共聚物之製造方法為將幾丁聚醣、聚乙二醇溶解於乳酸/甘醇酸水溶液中,直接進行聚縮合反應而得幾丁聚醣接枝聚(乳酸/甘醇酸)共聚物、聚(乳酸/甘醇酸)與聚乙二醇共聚物以及其組合物;或先合成幾丁聚醣接枝聚(乳酸/甘醇酸)共聚物,再與聚乙二醇共聚形成幾丁聚醣-聚(乳酸/甘醇酸)-聚乙二醇共聚物。其具有溫感性與抗菌性等特性。110、120、130、140、150‧‧‧步驟
