【摘要】利用计算机模拟方法 (耗散粒子动力学) 研究了双响应性嵌段聚合物修饰的纳米孔的开关效应。通过在纳米孔内接枝具有温度和pH响应的嵌段聚合物 (N-异丙基丙烯酰胺和丙烯酸) , 研究不同嵌段序列 (即wallPNIPAM-PAA或wall-PAA-PNIPAM) 对纳米孔开关效应的影响, 结果表明, 只有wall-PNIPAM-PAA嵌段序列可以实现纳米孔在不同条件下的开关效应。同时还探究了接枝密度、链长和嵌段比例对纳米孔开关效应的影响, 结果表明, 中高等接枝密度、适合的链长和中等比例的嵌段比可以实现不同特征的纳米孔, 用于控制纳米孔的开关效应。
【基金资助】 国家自然科学基金项目 (21776093) ; 广东省自然科学基金项目 (2014A030312007) ;
Computer simulations on switching effect of nanopores modified by dual-responsive block polymers
【Abstract】The switching effect of the dual-responsive block polymer modified nanopore was studied by computer simulation method (dissipative particle dynamics). The dual-responsive block polymers were grafted into nanopores with temperature responsive (N-isopropylacrylamide, PNIPAM) and pH responsive (acrylic acid, PAA) polymers. The effect of different block sequences (wall-PNIPAM-PAA or wall-PAA-PNIPAM) on the nanopore switching was studied. The results show that only the wall-PNIPAM-PAA block sequence can realize the different switching effects of nanopores under different conditions. Meanwhile, the effects of different grafting density, chain length and different block ratio on the nanopore switching effect were also investigated. The results show that different nanopores can be realized at the moderate to high grafting density, the suitable chain length and the medium block ratio, which can be used to control the size of the switch.
【Keywords】 computer simulation; nanopore; polymers; pH-responsive; temperature-responsive; switching effect;
【Funds】 National Natural Science Foundation of China (21776093); Natural Science Foundation of Guangdong Province (2014A030312007);
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