聚乳酸-衣康酸酐共聚物的制备与表征

Preparation and characterization of polylactide-itaconic anhydride copolymer

为了改善聚乳酸疏水性和活性基团少的缺点,合成了一种新型的聚乳酸-衣康酸酐(PLA-co-IT)材料。采用过氧化苯甲酰为引发剂,将甲基丙烯酸酐改性的聚乳酸与衣康酸酐共聚,并通过傅里叶变换红外光谱(FT-IR)、核磁氢谱(1 H NMR)、差式扫描量热分析(DSC)等对产物PLA-co-IT进行了表征。FT-IR和1 H NMR结果都表明PLA-co-IT的成功合成。共聚物上的酸酐基团采用罗丹明比色法进行测定,结果表明,随着投料比的增加,产物中衣康酸酐的含量也随着增加;DSC结果表明,PLA-co-IT在144.4℃出现熔化峰,玻璃化温度和分解温度略高于原料PLA。

In order to improve the hydrophilicity and increase the number of available reactive functional groups of polylactide（PLA）,a new PLA-bassed materials（PLA-co-IT） was synthesized.Using the benzoyl peroxide as initiator,methacrylic anhydride modified PLA and itaconic anhydride were copolymerized in toluene.The grafting percentage of the copolymers was analyzed by the modified rhodamine-carboxyl interaction method,and structure of copolymers was characterized by infrared spectrum（IR） and 1H nuclear magnetic resonance spectrum（1H-NMR）.The results showed that the grafting percentage was increased with the increasing of itaconic anhydride percenrage in reactants.The glass transition temperature and decomposition temperature of PLA-co-IT were higher than these of PLA.