Effects of N-benzylpyrazinium hexafluoroantimonate concentration on rheological properties in cationic epoxy cure system

The rheological properties and initiation mechanism during the reactions of new catalytic (N-benzylpyrazinium hexafluoroantimonate, BPH) epoxy thermosetting system with increase of BPH concentration have been studied by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and steady shear measurements. This cationic catalyst system turned out to have an availability as thermal latent initiator in the epoxy curing reaction. The dependence of viscosity on processing variables could be explained by structural change owing to the composition dependence of initiation reactions with increasing of BPH concentration. The temperature dependence on the induction time is well described by the Arrhenius expression, and the activation energies (E_t) have similar values for various compositions, which indicates that the overall curing mechanisms are nearly same.