Abstract: Graft copolymerization of acrylamide（AM）and acrylic acid（AA）onto cassava starch was conducted in a five-component inverse emulsion system with potassium permanganate as initiator. Effects of reaction temperature and time，concentrations of initiator and monomer，the ratio of AM to AA on the graft percent and graft efficiency were investigated. Structure of the obtained St-g-AM/AA ternary copolymer was characterized using Fourier transform infrared spectroscopy（FTIR）and scanning electronic microscope（SEM）. Results illustrated that all the factors of reaction temperature and time，initiator and monomer concentrations，and the AM to AA monomer ratio showed predominant influences on the graft copolymerization. FTIR and SEM analysis proved that graft copolymerization reaction occurs at the starch particle surface，and both PAM and PAA have been successfully grafted onto the starch molecules.

摘要： 以丙烯酰胺（AM）和丙烯酸（AA）为接枝单体，采用反相乳液聚合技术对木薯淀粉进行接枝共聚改性，生成淀粉-丙烯酰胺-丙烯酸三元接枝共聚物（St-g-AM/AA）。考察反应温度和时间、引发剂和单体浓度、单体配比等因素对淀粉三元接枝共聚反应过程的影响规律，并通过红外光谱等表征共聚物结构。实验结果显示：引发剂浓度、单体浓度和单体比、反应温度和时间等因素对三元接枝共聚改性反应影响显著；红外光谱和电镜扫描表征证明接枝共聚反应发生在淀粉颗粒表面，经三元接枝共聚反应淀粉已被AM和AA成功改性。