A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine base...A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.展开更多
基金Project(21376271)supported by the National Natural Science Foundation of ChinaProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan Project,ChinaProjects(201810533078,S2020105330395)supported by the Undergraduates Innovative Training Foundation of Central South University,China。
文摘A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.
