|Name||Miss Shalini Jayaraman Rukmani|
|Organization||University of Florida|
A FLEXIBLE POLYMER CHAIN IN SOLVENTS: A GRADUATE-LEVEL MOLECULAR DYNAMICS EXERCISE
Shalini J. Rukmani1, Grit Kupgan1, Coray M. Colina1,2
1 Department of Materials Science and Engineering, University of Florida, Gainesville, 32611, USA
Polymer solubility is utilized in several applications including membrane design, microelectronics, and biomedical fields. Computational studies of polymers provide details at the molecular level that are difficult to access by experimental techniques. In addition to complementing experimental findings, molecular simulations predict important structural, thermodynamic and diffusion properties. The purpose of this graduate-level exercise is for students to understand, verify, and interpret the results obtained from molecular dynamics simulations of polymer-solvent systems. To accomplish this objective, the behavior of a chain of poly(methyl methacrylate) (PMMA) in three solvents (acetone (good), acetonitrile (theta) and water (bad)) is investigated. The radius of gyration (Rg) is used to validate the simulation model and depict the conformational differences in the presence of these solvents. Simulations are performed near the theta temperature to study the coil to globule transition of PMMA in acetonitrile. Additionally, the optimization of simulation parameters, including box size effects and cutoff distance for interactions, is studied. The effect of these parameters on computational time and accuracy is discussed. This exercise, designed for first-year graduate or senior undergraduate level classes, is expected to provide students with insight into the behavior of individual polymer chains in solvents, as well as molecular simulations.