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arXiv · 1802.09002

Scaling Behavior of Anisotropy Relaxation in Deformed Polymers

Christopher N. Lam·Wen-Sheng Xu·Wei-Ren Chen·Zhe Wang·Christopher B. Stanley·Jan-Michael Y. Carrillo·David Uhrig·Weiyu Wang·Kunlun Hong·Yun Liu·Lionel Porcar·Changwoo Do·Gregory S. Smith·Bobby G. Sumpter·Yangyang Wang
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Abstract

Drawing an analogy to the paradigm of quasi-elastic neutron scattering, we present a general approach for quantitatively investigating the spatiotemporal dependence of structural anisotropy relaxation in deformed polymers by using small-angle neutron scattering. Experiments and non-equilibrium molecular dynamics simulations on polymer melts over a wide range of molecular weights reveal that their conformational relaxation at relatively high momentum transfer $Q$ and short time can be described by a simple scaling law, with the relaxation rate proportional to $Q$. This peculiar scaling behavior, which cannot be derived from the classical Rouse and tube models, is indicative of a surprisingly weak direct influence of entanglement on the microscopic mechanism of single-chain anisotropy relaxation.

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Christopher N. Lam, Wen-Sheng Xu, Wei-Ren Chen, Zhe Wang, Christopher B. Stanley, Jan-Michael Y. Carrillo, David Uhrig, Weiyu Wang, Kunlun Hong, Yun Liu, Lionel Porcar, Changwoo Do, Gregory S. Smith, Bobby G. Sumpter, Yangyang Wang. 2018-02-25. Scaling Behavior of Anisotropy Relaxation in Deformed Polymers. https://doi.org/10.1103/physrevlett.121.117801

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