Distinct Viscoelasticity of Nanoparticle-Tethering Polymers Revealed by Nonequilibrium Molecular Dynamics Simulations
Distinct Viscoelasticity of Nanoparticle-Tethering Polymers Revealed by Nonequilibrium Molecular Dynamics Simulations
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DOI：
10.1021/acs.jpcc.7b10455
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发表时间：
2017-12
影响因子：
3.7
通讯作者：
Pengxiang Xu;Jiaping Lin;Liangshun Zhang
中科院分区：
文献类型：
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作者：
Pengxiang Xu;Jiaping Lin;Liangshun Zhang
我们采用非平衡态分子动力学模拟来研究纳米颗粒束缚聚合物的粘弹性。研究了纳米粒子-聚合物相互作用和分子结构对粘弹性的影响。结果表明，具有吸引力的纳米颗粒-聚合物相互作用的纳米颗粒-束缚聚合物表现出增强的存储和损耗模量相对于均聚物或裸纳米颗粒/聚合物共混物。此外，纳米颗粒系链聚合物的存储和损耗模量可以通过调节其分子结构（例如增加纳米颗粒直径或减小聚合物链长）来进一步增强。从物理根源上看，纳米粒子与聚合物之间的相互作用、共价键的束缚作用以及纳米粒子的阻碍作用使聚合物的动力学行为变慢，从而导致了动态模量的提高。本文的工作不仅揭示了纳米颗粒独特粘弹性的物理起源，而且还揭示了纳米颗粒的粘弹性与纳米颗粒的粘弹性之间的关系。
We employed nonequilibrium molecular dynamics simulations to study viscoelastic properties of nanoparticle-tethering polymers. Effects of nanoparticle–polymer interaction and molecular architecture on the viscoelasticity are investigated. The results show that the nanoparticle-tethering polymers with attractive nanoparticle–polymer interaction exhibit enhanced storage and loss moduli relative to the homopolymers or bare nanoparticle/polymer blend. In addition, the storage and loss moduli of nanoparticle-tethering polymers can be further enhanced through tuning their molecular architectures, such as increasing the nanoparticle diameter or decreasing the polymer chain length. From the physical origin, the enhancement of dynamic moduli originates from the slowdown of polymer dynamics, which arises from the attractive nanoparticle–polymer interaction, the tethering covalent bond, and the obstacle of nanoparticles. The present work not only reveals the physical origin of distinct viscoelasticity of nanoparticl...