规整接枝的聚丙烯酰胺及其络合物作化学阀

采用大单体技术合成带有规整聚苯乙烯支链的聚丙烯酰胺 (PAM -g -PSt)。产物用萃取法纯化并用红外光谱表征。接枝共聚物具有两亲性质 ,呈现良好的乳化性。PAM -g -PSt与带有规整聚甲基丙烯酸甲酯 (PMMA)支链的聚甲基丙烯酸 (PMAA -g -PMMA)以摩尔比nPAM/nPMAA=1共混 ,生成一种分子间络合物 ,其薄膜呈现化学阀的特性 ,通过改变介质的pH值而可逆地控制其渗透性。

Synthesis of Polyacrylamide with Uniform Polystyrene Grafts and Its Intermolecular Complex Used as Chemical Valve

WT5BZ]Polyacrylamide with well-defined polystyrene grafts(PAM-g-PSt)was synthesized via macromonomer technique.Polymerization conditions and reactivity ratio for the copolymerization were studied.The graft copolymers were purified by extractions with methanol and hot cyclohexane and characterized with IR spectrum.The graft copolymers are amphiphilic,exhibiting good emulsifying properties.When PAM-g-PSt was blended with polymethacrylic acid(PMAA) grafted with poly(methylmethacrylate) in solution in a molar ratio of n PAM /n PMAA =1,an intermolecular complex membrane was formed,which was characterized by IR spectrum.The membrane behaves as a chemical valve,its permeability can be controlled reversibly by changing the pH value.