title: Thermodynamic and mechanical properties of epoxy resin DGEBF crosslinked with DETDA by molecular dynamics.
abstract: Fully atomistic molecular dynamics (MD) simulations were used to predict the properties of diglycidyl ether of bisphenol F (DGEBF) crosslinked with curing agent diethyltoluenediamine (DETDA). This polymer is a commercially important epoxy resin and a candidate for applications in nanocomposites. The calculated properties were density and bulk modulus (at near-ambient pressure and temperature) and glass transition temperature (at near-ambient pressure). The molecular topology, degree of curing, and MD force-field were investigated as variables. The models were created by densely packing pre-constructed oligomers of different composition and connectivity into a periodic simulation box. For high degrees of curing (greater than 90%), the density was found to be insensitive to the molecular topology and precise value of degree of curing. Of the two force-fields that were investigated, cff91 and COMPASS, the latter clearly gave more accurate values for the density as compared to experiment. In fact, the density predicted by COMPASS was within 6% of reported experimental values for the highly crosslinked polymer. The predictions of both force-fields for glass transition temperature were within the range of reported experimental values, with the predictions of cff91 being more consistent with a highly cured resin.
authors.affiliation: Department of Chemical Engineering, Texas A&M University, College Station, TX 77843-3122, USA. jtack13@yahoo.com
authors.forename: Jeremy L
authors.initials: JL
authors.lastname: Tack
authors.forename: David M
authors.initials: DM
authors.lastname: Ford
mesh_terms: D003198:Computer Simulation; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004853:Epoxy Resins / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010655:Phenylenediamines / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D011312:Pressure; D013816:Thermodynamics; D014050:Toluene / Q000031:analogs & derivatives* / Q000737:chemistry*; D044366:Transition Temperature
chemical_list: D003432:Cross-Linking Reagents; D004853:Epoxy Resins; D010655:Phenylenediamines; D011108:Polymers; C000611381:2,6-diamino-3,5-diethyltoluene; D014050:Toluene