无热薄膜中聚合物-纳米粒子混合物的表面分离和体相聚集：控制相行为的策略。

Surface Segregation and Bulk Aggregation in an Athermal Thin Film of Polymer-Nanoparticle Blends: Strategies of Controlling Phase Behavior.

机构信息

Department of Chemical Engineering, National Taiwan University , Taipei 106, Taiwan.

Department of Chemical and Materials Engineering, Department of Physics, National Central University , Jhongli 320, Taiwan.

出版信息

Langmuir. 2017 Mar 14;33(10):2639-2645. doi: 10.1021/acs.langmuir.6b04681. Epub 2017 Feb 28.

DOI:10.1021/acs.langmuir.6b04681

PMID:28221802

Abstract

The phase behavior of an athermal film of a polymer-nanoparticle blend (PNB) driven by depletion attraction is investigated by dissipative particle dynamics for nanospheres and nanocubes. Surface segregation is observed at low nanoparticle concentrations, while bulk aggregation is seen at high concentrations. Surface excess and the aggregation number can be controlled by tuning the nanoparticle concentration. As surface-roughened or polymer-grafted nanoparticles are used, uniform PNBs are acquired due to the lack of depletion. Thus, addition of surface-roughened nanoparticles into PNBs of smooth nanoparticles can be employed to tune the phase characteristics. It is found that bulk aggregation is suppressed for both polymer-nanosphere and polymer-nanocube blends. However, surface segregation is impeded for polymer-nanosphere blend but enhanced for polymer-nanocube blend owing to the distinct influence of the nanoparticle shape on depletion.

摘要

通过耗散粒子动力学研究了由耗散吸引力驱动的无热聚合物-纳米粒子共混物（PNB）的相行为，研究对象为纳米球和纳米立方体。在低纳米粒子浓度下观察到表面偏析，而在高浓度下则观察到体相聚集。通过调整纳米粒子浓度可以控制表面过剩和聚集数。当使用表面粗糙化或聚合物接枝的纳米粒子时，由于缺乏耗散，会得到均匀的 PNB。因此，可以将表面粗糙化的纳米粒子添加到光滑纳米粒子的 PNB 中，以调节相特征。研究发现，聚合物-纳米球和聚合物-纳米立方体共混物的体相聚集都受到抑制。然而，由于纳米粒子形状对耗散的影响不同，对于聚合物-纳米球共混物，表面偏析受到阻碍，而对于聚合物-纳米立方体共混物，表面偏析则得到增强。