Abstract
A series of commercial difunctional benzoxazine monomers are characterised carefully using thermal and thermo-mechanical techniques before constructing representative polymer networks using molecular simulation techniques. Good agreement is obtained between replicate analyses and for the kinetic parameters obtained from differential scanning calorimetry data (and determined using the methods of Kissinger and Ozawa). Activation energies range from 85-108 kJ/mol (Kissinger) and 89-110 kJ/mol (Ozawa) for the uncatalysed thermal polymerisation reactions, which achieve conversions of 85-97 %. Glass transition temperatures determined from differential scanning calorimetry and dynamic mechanical thermal analysis are coomparable, ranging from BA-a (151 °C, crosslink density 3.6 x 10-3 mol cm-3) containing the bisphenol A moiety to BP-a, based on a phenolphthalein bridge (239-256 °C, crosslink density 5.5-18.4 x 10-3 mol cm-3, depending on formulation). Molecular dynamics simulations of the polybenzoxazines generally agree well with empirical data, indicating that representative networks have been modelled.