Curing behaviour of epoxy resin with a diamine containing heterocyclic rings

The curing behaviour of a new epoxy curing agent, 2,6-di (p-aminophenyl) benzo[1.2.5.4] bisoxazole (DIABO) was discussed. Diglycidyl-4,5- epoxycyclohexane-1,2-dicarboxylate (TDE) was cured with a mixture of DIABO and diaminodiphenylsulfone (DDS). The aspects investigated including the curing procedure, reaction kinetics parameters and the heat resistance of the product. Average apparent activation energy of the resin's curing reaction was 63.55 kJ/mol, calculated according to the Kissinger and the Ozawa methods. The glass transition temperature was 261°C and 257°C determined by torsional braid analysis (TBA) and differential scanning calorimetry (DSC) respectively. The integral procedural decomposition temperature (IPDT) was 814°C, respectively. Char residue was 44.58% at 572°C Compared to cure with TDE/DDS, these properties were improved by 18%, 8%, 30% and 50%, respectively.