Thermo-responsive poly(N-isopropylacrylamide-co-styrene)[P(NIPAM-co-St)] hydrogel microspheres were prepared by surfactant-free emulsion polymerization. The effects of initiator dosage, stirring rate, phase ratio and ...Thermo-responsive poly(N-isopropylacrylamide-co-styrene)[P(NIPAM-co-St)] hydrogel microspheres were prepared by surfactant-free emulsion polymerization. The effects of initiator dosage, stirring rate, phase ratio and polymerization time on particle size and monodispersity were investigated.The results showed that, with increasing initiator dosage,mean diameter increased slightly to a maximum, and then decreased drastically; meanwhile, the monodispersity of the particles became a little better at first, and then became worse significantly. With increasing stirring rate,particle diameter decreased while the monodispersity became worse. When the amount of phase rate increased, the mean diameter became larger simply, whereas the monodispersity became worse firstly and then became better again. As the polymerization proceeded, the mean diameter of the particles hardly changed, and the monodispersity became better gradually. The microspheres prepared under the optimum experimental conditions showed satisfactory particle size and monodispersity.展开更多
Monodisperse polystyrene microspheres are prepared by shell porous glass(SPG)\|suspension polymerization. The influences of SPG on size and size dispersity of the microspheres are investigated. The properties of the m...Monodisperse polystyrene microspheres are prepared by shell porous glass(SPG)\|suspension polymerization. The influences of SPG on size and size dispersity of the microspheres are investigated. The properties of the microspheres are studied by GPC, TEM and SEM. The results indicate that the polystyrene microspheres possess definite monodispersibity and their particle size is in the range of 5～12?μm.展开更多
刚柔嵌段共聚物聚苯基喹啉 b 聚苯乙烯(PPQ b PS)在选择性溶剂中具有自组装行为。该共聚物在1mg·mL-1的V(三氟乙酸)∶V(二氯甲烷)=1∶1的溶液中形成胶束,室温下易自组装成平均粒径为2μm的微球,微球粒径随着PPQ聚合度的增大而增... 刚柔嵌段共聚物聚苯基喹啉 b 聚苯乙烯(PPQ b PS)在选择性溶剂中具有自组装行为。该共聚物在1mg·mL-1的V(三氟乙酸)∶V(二氯甲烷)=1∶1的溶液中形成胶束,室温下易自组装成平均粒径为2μm的微球,微球粒径随着PPQ聚合度的增大而增大,具有单分散性,同时所形成稀溶液的最强吸收波长为376nm。文中对刚柔嵌段共聚物自组装制备单分散性微球的机理进行了初步探讨。展开更多
基金国家自然科学基金 (No 2 0 2 0 60 19)教育部留学回国人员科研启动基金 (No [2 0 0 2 ] 2 47)资助项目~~
文摘Thermo-responsive poly(N-isopropylacrylamide-co-styrene)[P(NIPAM-co-St)] hydrogel microspheres were prepared by surfactant-free emulsion polymerization. The effects of initiator dosage, stirring rate, phase ratio and polymerization time on particle size and monodispersity were investigated.The results showed that, with increasing initiator dosage,mean diameter increased slightly to a maximum, and then decreased drastically; meanwhile, the monodispersity of the particles became a little better at first, and then became worse significantly. With increasing stirring rate,particle diameter decreased while the monodispersity became worse. When the amount of phase rate increased, the mean diameter became larger simply, whereas the monodispersity became worse firstly and then became better again. As the polymerization proceeded, the mean diameter of the particles hardly changed, and the monodispersity became better gradually. The microspheres prepared under the optimum experimental conditions showed satisfactory particle size and monodispersity.
基金Natural Science Foundation of Shandong Province of China(Y2007F44)National Natural Science Foundation of China(50902059)+1 种基金Department of Education Fund of Shandong Province(J08LA02)from Shandong Province Taishan Scholarship foundation research grants
文摘Monodisperse polystyrene microspheres are prepared by shell porous glass(SPG)\|suspension polymerization. The influences of SPG on size and size dispersity of the microspheres are investigated. The properties of the microspheres are studied by GPC, TEM and SEM. The results indicate that the polystyrene microspheres possess definite monodispersibity and their particle size is in the range of 5～12?μm.
文摘 刚柔嵌段共聚物聚苯基喹啉 b 聚苯乙烯(PPQ b PS)在选择性溶剂中具有自组装行为。该共聚物在1mg·mL-1的V(三氟乙酸)∶V(二氯甲烷)=1∶1的溶液中形成胶束,室温下易自组装成平均粒径为2μm的微球,微球粒径随着PPQ聚合度的增大而增大,具有单分散性,同时所形成稀溶液的最强吸收波长为376nm。文中对刚柔嵌段共聚物自组装制备单分散性微球的机理进行了初步探讨。
