Molecular Dynamics Simulations of Gas Transport in Polymer Films

Parallel molecular dynamics simulations have been carried out to determine the permeability of O$_{2}$ and N$_{2}$ through polyethylene terephthalate, polypropylene and cis(1-4) polybutadiene. The permeability of both mixed and unmixed gas penetrants is studied within films of these well known gas barrier polymers. Results are obtained either through the solubility and diffusion (i.e. $P=D*S$) or via the permeability directly. Encouraging results are obtained. Additional analysis focuses on ``unmixed/mixed gas'' intracomparisons of the simulated permeability data in addition to corresponding penetrant and host polymer local dynamics.