Lanthanide triflates as curing initiators for solid DGEBA resin:: Thermal and mechanical characterization

A new class of cationic initiators, lanthanide triflates, has been studied in the curing of diglycidyl ether of bisphenol-A (DGEBA). Two metal salts (Erbium and Ytterbium (111) trifluoromethanesulfonate) in various proportions (0.5, 1, and 2 parts per hundred of resin) have been used and the thermal and mechanical properties of the thermosets compared to a common solid epoxy system (crosslinked with o-tolylbiguanide). The kinetics of these processes has been evaluated by the isoconversional method that has been proved to be an excellent tool to predict the principal curing parameters (conversion/time/ temperature). Their mechanical properties have been evaluated by dynamic mechanical thermal analysis (DMTA), stress-strain curves, impact resistances and adhesion to metallic substrates, and the thermal characteristics were measured by calorimetry (DSC) and thermogravimetry (TGA). (C) 2007 Wiley Periodicals, Inc.