【摘要】 研究了以二羟基二过碘酸合镍(Ⅳ)钾为引发剂,于碱性介质中引发甲基丙烯酸甲酯(MMA)单体在聚丙烯酰胺(PAAM)上的自由基接枝共聚合反应;考察了引发剂浓度、MMA与PAAM质量比和反应温度对接枝参数的影响,获得了最佳实验条件,即Ni(Ⅳ)引发剂浓度3.107×10-4mol／L,MMA与PAAM质量比小于10,反应温度35℃;在此条件下,接枝共聚物效率约80％,MMA转化率约50％,接枝百分比300％左右。用红外光谱、热重分析和X射线衍射对接枝共聚物进行表征,表明共聚物由PAAM和聚甲基丙烯酸甲酯(PMMA)两部分组成;共聚物的抗吸潮性和热性能比纯PAAM提高,结晶度比纯PAAM略小。更多还原

【Abstract】 Graft copolymerization of methyl methacrylate onto polyacrylamide using diperiodatonickelate as initiator in alkaline medium was studied. The effects of reaction conditions including initiator concentration, mass ratio of MMA to PAAM, and reaction temperature on the graft parameters were examined. The optimum reaction conditions were obtained as follows:the concentration of Ni(Ⅳ) was 3.107×10-4 mol/L,mass ratio of MMA to PAAM less than 11 at 35 ℃ . Under such conditions, the grafting efficiency, conversion of MMA and grafting rate were about 80% ,50% and 300% respectively.PAAM - g- PMMA copolymer was characterized by FT - IR,TGA and X - ray diffraction. The result showed that the copolymer was composed of PAAM and PMMA with better resistance to moisture absorption and heat stability but slightly less crystallinity than pure PAAM.更多还原