A molecular simulation study of the glass transition of cross-linkedpoly(dicyclopentadiene) networks

Authors

Robert M. Elder, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD
Jan W. Andzelm, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD
Timothy W. Sirk, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD

Date of this Version

2015

Citation

Chemical Physics Letters 637 (2015) 103–109

Abstract

Cross-linked polymer networks are widely used as structural and protective materials, which requirestrength and toughness. Experiments have shown that cross-linked poly(dicyclopentadiene) (pDCPD)networks provide similar strength but superior fracture toughness relative to commonly-used networkchemistries like epoxy. To better understand pDCPD, we use atomistic molecular dynamics to study theproperties of pDCPD networks across the glass transition as a function of molecular weight between cross-links. Moreover, we identify molecular mechanisms that potentially control mechanical and transportproperties. The alpha-relaxation (the glass transition) is linked to intra-chain motions and large-scalesegmental motions, while sub-T_g are linked with more localized motions.