Nanoparticle dynamics in semidilute polymer solutions: Rings versus linear chains
Nanoparticle dynamics in semidilute polymer solutions: Rings versus linear chains
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DOI：
10.1122/8.0000223
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发表时间：
2021-06
影响因子：
3.3
通讯作者：
Ren-peng Chen;Shivraj B. Kotkar;R. Poling-Skutvik;Michael P. Howard;A. Nikoubashman;J. Conrad;J. Palmer
中科院分区：
文献类型：
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作者：
Ren-peng Chen;Shivraj B. Kotkar;R. Poling-Skutvik;Michael P. Howard;A. Nikoubashman;J. Conrad;J. Palmer
本文采用混合分子动力学-多粒子碰撞动力学方法研究了纳米粒子在环状和线型聚合物半稀释溶液中的动力学行为。对于相同单体浓度的溶液，这两种体系结构的单体、聚合物质量中心和纳米颗粒的动力学一致。纳米颗粒的长时间扩散率遵循聚合物耦合理论的预测[Cai等人，Macromolecules 44，7853-7863（2011）]，表明纳米颗粒动力学与这里检查的两种聚合物结构的链段弛豫相关联。在中间的时间尺度上，纳米粒子的动力学的特点是subdiffusive指数，显着偏离耦合理论，并密切关注的聚合物。相反，纳米粒子的动力学强烈耦合到聚合物的质心运动的两个架构，而不是他们的分段动态。环连接的存在不影响纳米颗粒的长时间扩散率，但导致纳米颗粒和聚合物质量中心的亚扩散指数略有下降。
We study the dynamics of nanoparticles in semidilute solutions of ring and linear polymers using hybrid molecular dynamics–multiparticle collision dynamics simulations. The dynamics of the monomers, the polymer centers-of-mass, and the nanoparticles coincide for these two architectures for solutions of the same monomer concentration. The long time diffusivities of the nanoparticles follow the predictions of a polymer coupling theory [Cai et al., Macromolecules 44, 7853–7863 (2011)], suggesting that nanoparticle dynamics are coupled to segmental relaxations for both polymer architectures examined here. At intermediate time scales, the nanoparticle dynamics are characterized by subdiffusive exponents, which markedly deviate from coupling theory and closely follow those of the polymers. Instead, the nanoparticle dynamics are strongly coupled to the polymer center-of-mass motions for both architectures, rather than to their segmental dynamics. The presence of ring concatenations does not affect the long-time diffusivity of the nanoparticles but leads to a slight decrease in the subdiffusive exponents of the nanoparticles and the polymer center-of-mass.