N-Isopropylacrylamide and vinyl imidazole copolymer,P(NIPAM-co-VI),was synthesized by free radical emulsion polymerization.Then,the copolymer and silver nanoparticle composite,P(NIPAM-co-VI)-Ag,was pre-pared by in sit...N-Isopropylacrylamide and vinyl imidazole copolymer,P(NIPAM-co-VI),was synthesized by free radical emulsion polymerization.Then,the copolymer and silver nanoparticle composite,P(NIPAM-co-VI)-Ag,was pre-pared by in situ reduction of AgNO3 with NaBH4.Due to the coexistence of thermal-responsive PNIPAM and pH-responsive PVI,P(NIPAM-co-VI)and P(NIPAM-co-VI)-Ag exhibited both thermal and pH responsibility,their size would change while altering the temperature or pH of the circumvent.Their thermal and pH dual responsive properties were studied by dynamic light scattering(DLS).P(NIPAM-co-VI)-Ag could be stably dispersed in water at a pH range from 3.0 to 9.3,which is favorable to use P(NIPAM-co-VI)-Ag as a catalyst in the reduction reaction of p-nitrophenol.The reaction rate constant(kapp)increased with the decrease of pH or the increase of VI content in the copolymer.展开更多
基金support from the Na-tional Natural Science Foundation of China(Nos.51073042,51103026,51373035,and 51373040)the Shanghai Scientific and Technological Innovation Pro-ject(Nos.11JC1400600,10431903000 and 124119a2400)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20110071120006).
文摘N-Isopropylacrylamide and vinyl imidazole copolymer,P(NIPAM-co-VI),was synthesized by free radical emulsion polymerization.Then,the copolymer and silver nanoparticle composite,P(NIPAM-co-VI)-Ag,was pre-pared by in situ reduction of AgNO3 with NaBH4.Due to the coexistence of thermal-responsive PNIPAM and pH-responsive PVI,P(NIPAM-co-VI)and P(NIPAM-co-VI)-Ag exhibited both thermal and pH responsibility,their size would change while altering the temperature or pH of the circumvent.Their thermal and pH dual responsive properties were studied by dynamic light scattering(DLS).P(NIPAM-co-VI)-Ag could be stably dispersed in water at a pH range from 3.0 to 9.3,which is favorable to use P(NIPAM-co-VI)-Ag as a catalyst in the reduction reaction of p-nitrophenol.The reaction rate constant(kapp)increased with the decrease of pH or the increase of VI content in the copolymer.