Deformation of Chemically Heterogeneous Interfacial Layers of Polymer Nanocomposites
Deformation of Chemically Heterogeneous Interfacial Layers of Polymer Nanocomposites
复制标题
聚合物纳米复合材料化学异质界面层的变形
DOI：
10.1021/acsmacrolett.9b00821
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发表时间：
2019
影响因子：
7.015
通讯作者：
Akcora, Pinar
中科院分区：
文献类型：
--
作者：
Yang, Siyang;Akcora, Pinar
纳米颗粒周围的缠结界面聚合物层的动力学决定了聚合物纳米复合材料的线性流变性能。在这项研究中，纳米复合材料的非线性弹性性能的大振幅振荡剪切（LAOS）流下，揭示界面化学不均匀性的聚合物接枝和聚合物吸附的纳米复合材料的变形机制的影响。吸附聚甲基丙烯酸甲酯（PMMA）层比PMMA接枝层表现出更强的界面硬化和增强。界面层的化学异质性，由聚合物吸附和低接枝密度的颗粒，在较小的应变比聚（环氧乙烷）（PEO）矩阵变形。界面松散结合的PMMA和PEO表现出硬化在低应变，由于增强链混合和缠结。这些结果表明，在界面层的化学和动态的不均匀性有显着的重要性，在设计自适应聚合物纳米复合材料的大剪切变形。
Dynamics of entangled interfacial polymer layers around nanoparticles determine the linear rheological properties of polymer nanocomposites. In this study, the nonlinear elastic properties of nanocomposites are examined under large-amplitude oscillatory shear (LAOS) flow to reveal the effect of interfacial chemical heterogeneity on the deformation mechanism of polymer-grafted and polymer-adsorbed nanoparticle composites. Adsorbed-poly(methyl methacrylate) (PMMA) layers presented stronger interfacial stiffening and reinforcement than PMMA-grafted layers. Chemical heterogeneities of interfacial layers, provided by polymer-adsorbed and low graft density particles, deformed at smaller strains than the poly(ethylene oxide) (PEO) matrix. Interfaces of loosely bound PMMA and PEO exhibited stiffening at low strains due to the enhanced chain mixing and entanglements. These results demonstrate that chemical and dynamic heterogeneities in interfacial layers have significant importance in designing adaptive polymer nanocomposites for large shear deformation.