Developing predictive models for polycyanurates through a comparative study of molecular simulation and empirical thermo-mechanical data

Using a parameter set (RDA-DR2.21_Inv) previously published by our group, both the atom-to-atom connectivities and geometries and the physical and mechanical properties of poly [bis-4-(4-cyanatophenoxy)phenyl sulphone] have been simulated with remarkable accuracy. Molecular dynamics simulation, carried out on the polymer structure at a variety of experimental temperatures, yields a transition temperature of ca. 510-520 K, which can be equated with the empirical glass transition temperature (T-g) for the polycyanurate. The same dicyanate was prepared experimentally and characterised using dynamic mechanical analysis (yielding an empirical T-g of ca. 519 K) and thermo-mechanical analysis (yielding an empirical T-g of 508-528 K). The effect of incomplete cure of the monomer or development of structural defects in the network on the thermo-mechanical properties is also examined using molecular simulation. (c) 2005 Elsevier Ltd. All rights reserved.