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嵌段共聚物聚(N-异丙基丙烯酰胺)-b-聚(4-乙烯基吡啶)(PNPIAM-b-P4VP)在pH6.5的水溶液中自组装成,以聚(4-乙烯基吡啶)为胶束的核,以热响应聚(N-异丙基丙烯酰胺)为胶束壳的球形胶束.通过与4VP基络合作用,将氯铂酸(H2PtCl6)导入胶束的核中,原位还原获得胶束负载2~4nm的铂纳米粒子的温度敏感型催化体系.结果显示,最低临界溶解温度(LCST)为33℃,在LCST以下,催化反应速率会随着温度的升高而提高;在LCST以上,PNPIAM嵌段变成疏水而塌缩在催化剂表面,阻碍了反应物的扩散,因此胶束负载的铂纳米粒子的催化活性会随着温度的上升而下降.
The block copolymer poly (N-isopropylacrylamide) -b-poly (4-vinylpyridine) (PNPIAM-b-P4VP) was self-assembled in an aqueous solution of pH 6.5, Pyridine) is the micelle nucleus, which is a spherical micelle of micellar shell by thermal reaction of poly (N-isopropylacrylamide) .Chloroplatinic acid (H2PtCl6) is introduced into the micellar nucleus through the complexation with 4VP group The results showed that the lowest critical solution temperature (LCST) was 33 ℃. Under LCST, the catalytic reaction rate increased with the increase of temperature High and increased; above the LCST, the PNPIAM block becomes hydrophobic and collapses on the catalyst surface, hindering the diffusion of the reactants, so the catalytic activity of the micellar loaded platinum nanoparticles decreases with increasing temperature.