Zuo Biao, Zhou Hao, Davis Mary J B, Wang Xinping, Priestley Rodney D
Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2019 May 31;122(21):217801. doi: 10.1103/PhysRevLett.122.217801.
Interfaces play an important role in modifying the dynamics of polymers confined to the nanoscale. We demonstrate that the distance over which an interface suppresses molecular mobility in poly(styrene) thin films can be systematically increased by tens of nanometers by controlling the chain of conformation, i.e., the height of the loops in irreversibly adsorbed nanolayers. These effects arise from topological interaction between adsorbed and neighboring unadsorbed chains, respectively, which increase their motional coupling to facilitate the propagation of suppressed dynamics originating at the interface, thus highlighting the ability to manipulate interfacial effects by local conformation of chains in adsorbed nanolayers.
界面在改变受限于纳米尺度的聚合物动力学方面起着重要作用。我们证明,通过控制构象链,即不可逆吸附纳米层中链环的高度,界面抑制聚(苯乙烯)薄膜中分子迁移率的距离可以系统地增加数十纳米。这些效应分别源于吸附链与相邻未吸附链之间的拓扑相互作用,这增加了它们的运动耦合,以促进源自界面的受抑制动力学的传播,从而突出了通过吸附纳米层中链的局部构象来操纵界面效应的能力。