Self assembly of an amphiphilic diblock copolymer polysyrene b polyvinylbenzoic acid in ethanol,which is a selective solvent for the polybenzoic acid segment was studied by means of transmission electron microscopy.Th...Self assembly of an amphiphilic diblock copolymer polysyrene b polyvinylbenzoic acid in ethanol,which is a selective solvent for the polybenzoic acid segment was studied by means of transmission electron microscopy.The diblock copolymers can self assemble into nano scale aggregates with polystyrene segment as the core and polyvinylbenzoic acid segment as the corona.The morphology of the aggregates is mainly controlled by the ratio of the two segment of the diblock copolymer.As the content of the ethanol insoluble polystyrene segment increased,the morphology can be changed from spheres to rods.The diameter of the aggregates increases slightly with concentration and decreases with the addition of CoCl 2 salt.展开更多
通过原子转移自由基聚合技术(Atom Transfer Radical Polymerization,ATRP)合成聚乙二醇单甲醚/聚甲基丙烯酸甲酯(MPEG-b-PMMA)两亲性嵌段共聚物,运用傅立叶变换红外光谱(FT-IR)、核磁共振氢谱(^1H-NMR)及凝胶渗透色谱(GPC...通过原子转移自由基聚合技术(Atom Transfer Radical Polymerization,ATRP)合成聚乙二醇单甲醚/聚甲基丙烯酸甲酯(MPEG-b-PMMA)两亲性嵌段共聚物,运用傅立叶变换红外光谱(FT-IR)、核磁共振氢谱(^1H-NMR)及凝胶渗透色谱(GPC)对所合成的两亲性嵌段共聚物进行表征。然后,将所合成的MPEG-b-PMMA两亲性嵌段共聚物与聚偏氟乙烯(PVDF)进行溶液共混,通过浸没沉淀相转化法制备MPEG-b-PMMA/PVDF共混超滤膜。膜性能测试结果表明:与PVDF膜相比,MPEG-b-PMMA/PVDF共混膜的亲水性、抗污染性、纯水通量及BSA截留率等性能均得到明显提高.展开更多
采用可逆加成-断裂链转移(RAFT)聚合法制备了以苯乙烯-马来酸酐交替共聚物(PSMA)与聚乙二醇甲基丙烯酸酯(MAPEG)组成的共聚物(PSMA-b-PMAPEG),经4-氨基偶氮苯(4-AAB)修饰得光响应性两亲性嵌段共聚物P(St-al-Ma/azo-MaIM)-b-PMAPEG。用...采用可逆加成-断裂链转移(RAFT)聚合法制备了以苯乙烯-马来酸酐交替共聚物(PSMA)与聚乙二醇甲基丙烯酸酯(MAPEG)组成的共聚物(PSMA-b-PMAPEG),经4-氨基偶氮苯(4-AAB)修饰得光响应性两亲性嵌段共聚物P(St-al-Ma/azo-MaIM)-b-PMAPEG。用红外光谱(FT-IR)、核磁共振(1 H NMR)、凝胶渗透色谱(GPC)对其结构进行表征。此共聚物在水中可自组装形成胶束,由透射电子显微镜(TEM)和动态光散射(DLS)表征可知胶束直径约100nm。用紫外-可见光谱法(UV-Vis)研究胶束溶液的吸光度随光照时间的变化;DLS和扫描电子显微镜(SEM)观察紫外光和可见光辐射对胶束粒径的影响,结果表明,胶束经365nm紫外光照射后,偶氮苯由反式结构转变成顺式结构,粒径增大;再经420nm可见光照射,偶氮苯结构又从顺式转变回反式,粒径减小到初始值。展开更多
文摘Self assembly of an amphiphilic diblock copolymer polysyrene b polyvinylbenzoic acid in ethanol,which is a selective solvent for the polybenzoic acid segment was studied by means of transmission electron microscopy.The diblock copolymers can self assemble into nano scale aggregates with polystyrene segment as the core and polyvinylbenzoic acid segment as the corona.The morphology of the aggregates is mainly controlled by the ratio of the two segment of the diblock copolymer.As the content of the ethanol insoluble polystyrene segment increased,the morphology can be changed from spheres to rods.The diameter of the aggregates increases slightly with concentration and decreases with the addition of CoCl 2 salt.
文摘通过原子转移自由基聚合技术(Atom Transfer Radical Polymerization,ATRP)合成聚乙二醇单甲醚/聚甲基丙烯酸甲酯(MPEG-b-PMMA)两亲性嵌段共聚物,运用傅立叶变换红外光谱(FT-IR)、核磁共振氢谱(^1H-NMR)及凝胶渗透色谱(GPC)对所合成的两亲性嵌段共聚物进行表征。然后,将所合成的MPEG-b-PMMA两亲性嵌段共聚物与聚偏氟乙烯(PVDF)进行溶液共混,通过浸没沉淀相转化法制备MPEG-b-PMMA/PVDF共混超滤膜。膜性能测试结果表明:与PVDF膜相比,MPEG-b-PMMA/PVDF共混膜的亲水性、抗污染性、纯水通量及BSA截留率等性能均得到明显提高.
文摘采用可逆加成-断裂链转移(RAFT)聚合法制备了以苯乙烯-马来酸酐交替共聚物(PSMA)与聚乙二醇甲基丙烯酸酯(MAPEG)组成的共聚物(PSMA-b-PMAPEG),经4-氨基偶氮苯(4-AAB)修饰得光响应性两亲性嵌段共聚物P(St-al-Ma/azo-MaIM)-b-PMAPEG。用红外光谱(FT-IR)、核磁共振(1 H NMR)、凝胶渗透色谱(GPC)对其结构进行表征。此共聚物在水中可自组装形成胶束,由透射电子显微镜(TEM)和动态光散射(DLS)表征可知胶束直径约100nm。用紫外-可见光谱法(UV-Vis)研究胶束溶液的吸光度随光照时间的变化;DLS和扫描电子显微镜(SEM)观察紫外光和可见光辐射对胶束粒径的影响,结果表明,胶束经365nm紫外光照射后,偶氮苯由反式结构转变成顺式结构,粒径增大;再经420nm可见光照射,偶氮苯结构又从顺式转变回反式,粒径减小到初始值。