William & Mary

Applied Science Seminar: Molecular Dynamics Modeling of Polymers

DATE:             Oct. 7, 10:00-11:00 am  
LOCATION:    York Room, Sadler Center  
 
Prof. Shengfeng Cheng
 
ABSTRACT:   
Molecular Dynamics Modeling of Polymers

Shengfeng Cheng

Department of Physics & Macromolecules and Interfaces Institute
Virginia Polytechnic Institute and State University

Molecular Dynamics (MD) simulations are increasingly applied to understand the structure, dynamics, and mechanics of polymers. In the first part of this seminar I will provide a survey of recent research activities in my group on modeling synthetic and biological polymers with either atomistic or coarse-grained (CG) MD simulations. On the synthetic polymer side, the topics include atomistic modeling of polyimides focusing on the computation of Tg and dielectric constant, CG modeling of the rheological properties of polyimides with branching, CG modeling of the interpolyelectrolyte complexes, polyelectrolyte-coated nanoparticles and their interactions and self-assembly, and nanoparticle-brush composites. On the biopolymer side, our effort is mainly devoted to a special supramolecular polymer named microtubules that are made of tubulin proteins and serve as a crucial component of the cytoskeleton. We have developed an intuition-based CG model that can be used to study the self-assembly and nanomechanics of microtubules. Recently we have made progress to connect this CG model to the known atomistic structure of tubulin proteins, including the direct computation of tubulin bond energies. We also demonstrate that a similar CG model can be applied to actin-filaments. Our research endeavors in other areas of soft matter physics, including bubble physics, evaporation, friction, adhesion, and crumpling, will also be briefly covered.

In the second part I will describe Virginia Tech’s Macromolecules and Interfaces Institute (http://www.mii.vt.edu/) and Macromolecular Science and Engineering graduate program (http://interdisciplinary.graduateschool.vt.edu/macr).