ChEMS Department Seminar

Event Date/Time: 
September 6, 2018 - 9:10am
Event Location: 
3540 EB
Yangyang Wang
Molecular Understanding of Polymer Flow and Deformation with Neutrons and Computer Simulation


Polymers are indispensable building blocks in a wide spectrum of advanced materials such as organic photovoltaics and fuel cells, membranes for gas separation, and energy-efficient lightweight composites. Understanding the flow and deformation behavior of polymers is crucial to not only the manufacturing of these materials, but also the functionality and performance of the end products. The Oak Ridge National Laboratory is home to several of the world's top supercomputers and a leading neutron science research facility. In this talk, I will describe our recent small-angle neutron scattering experiments [1] and large-scale molecular dynamics simulations [2] that directly challenge the foundation of a forty-year-old theory for polymer flow and deformation. The novel approaches developed in these studies provide us the opportunity to ask new questions about molecular motions of polymers in non-equilibrium state.


[1]          Z. Wang et al., Phys. Rev. X 7, 031003 (2017).

[2]          W.-S. Xu, J.-M. Y. Carrillo, C. N. Lam, B. G. Sumpter, and Y. Wang, ACS Macro Lett 7, 190 (2018).



Yangyang Wang is a Staff Scientist at the Center for Nanophase Materials Sciences (CNMS), Oak Ridge National Laboratory. His research focuses on experimental studies of dynamics of soft materials. By combining theoretical insights and a series of complementary techniques including rheology, dielectric spectroscopy, neutron scattering, and computer simulation, he has been trying to develop fundamental understanding of transport and relaxation phenomena in soft matter. He earned his PhD from the University of Akron in 2010. Before joining CNMS in 2014, he worked as a postdoctoral researcher in the Chemical Sciences Division of Oak Ridge National Laboratory and briefly as a research assistant professor at the Chemistry Department of the University of Tennessee, Knoxville.