Institute of Chemistry, Northeast Normal University , Changchun 130024 , P. R. China.
Department of Chemistry , Baotou Teachers College , Baotou 014030 , P. R. China.
Langmuir. 2018 Jul 17;34(28):8205-8214. doi: 10.1021/acs.langmuir.8b00414. Epub 2018 Jul 2.
A series of novel well-defined 8-hydroxyquinoline (HQ)-containing thermoresponsive amphiphilic diblock copolymers {poly(styrene- co-5-(2-methacryloylethyloxy-methyl)-8-quinolinol)- b-poly( N-isopropylacrylamide) P(St- co-MQ)- b-PNIPAm (P1,2), P(NIPAm- co-MQ)- b-PSt (P3,4)} and triblock copolymer poly( N-isopropylacrylamide)- b-poly(methyl-methacrylate- co-5-(2-methacryloylethyloxymethyl)-8-quinolinol)- b-polystyrene PNIPAm- b-P(MMA- co-MQ)- b-PSt (P5) were prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization, and their self-assembly behaviors were studied. Block copolymer P1-P5-stabilized gold nanoparticles (Au@P1-Au@P5) with a small size and a narrow distribution were obtained through the in situ reduction of gold precursors in an aqueous solution of polymer micelles with HQ as the coordination groups. The resulting Au@P nanohybrids possessed excellent catalytic activity for the reduction of nitrophenols using NaBH. The size, morphology, and surface chemistry of Au NPs could be controlled by adjusting the structure of block polymers with HQ in different block positions, which plays an important role in the catalytic properties. It was found that longer chain lengths of hydrophilic or hydrophobic segments of block copolymers were beneficial to elevating the catalytic activity of Au NPs for the reduction of nitrophenols, and the spherical nanoparticles (Au@P5) stabilized with triblock copolymers exhibit higher catalytic performance. Surprisingly, the gold nanowires (Au@P4) produced with P4 have the highest catalytic activity due to a large abundance of grain boundaries. Excellent thermoresponsive behavior for catalytic reaction makes the as-prepared Au@P hybrids an environmentally responsive nanocatalytic material.
一系列新型结构明确的含 8-羟基喹啉（HQ）的温敏两亲性嵌段共聚物{聚（苯乙烯-co-5-（2-甲基丙烯酰基乙氧基甲基）-8-喹啉醇）-b-聚（N-异丙基丙烯酰胺）P（St-co-MQ）-b-PNIPAm（P1,2），P（NIPAm-co-MQ）-b-PSt（P3,4）}和三嵌段共聚物聚（N-异丙基丙烯酰胺）-b-聚（甲基丙烯酸甲酯-co-5-（2-甲基丙烯酰基乙氧基甲基）-8-喹啉醇）-b-聚苯乙烯 PNIPAm-b-P（MMA-co-MQ）-b-PSt（P5）通过可逆加成-断裂链转移（RAFT）聚合制备，并研究了它们的自组装行为。通过 HQ 作为配位基团，在聚合物胶束水溶液中原位还原金前体，得到了具有小尺寸和窄分布的嵌段共聚物 P1-P5-稳定的金纳米粒子（Au@P1-Au@P5）。所得 Au@P 纳米杂化物具有优异的使用 NaBH 还原硝基苯酚的催化活性。通过调整具有 HQ 的不同嵌段位置的嵌段聚合物的结构，可以控制 Au NPs 的尺寸、形态和表面化学，这对催化性能起着重要作用。结果表明，亲水性或疏水性嵌段共聚物链段的长度越长，有利于提高 Au NPs 还原硝基苯酚的催化活性，并且使用三嵌段共聚物稳定的球形纳米粒子（Au@P5）表现出更高的催化性能。令人惊讶的是，由于晶界大量存在，用 P4 制备的金纳米线（Au@P4）具有最高的催化活性。对催化反应的优异温敏行为使制备的 Au@P 杂化物成为一种环境响应性纳米催化材料。
