Influence of interface interaction on enthalpy relaxation in polysiloxane-modified epoxy resin

摘要

The enthalpy relaxation and dynamic relaxation properties of phenol-formaldehyde novolac-cured o-cresol novolac epoxy resin modified with hydroxyl-terminated polysiloxane were studied by differential scanning calorimeter (DSC) and torsional pendulum analysis. The results show that the extent and rate of enthalpy relaxation are closely related to the amount of modifier and the ratio of modifier and coupling agent; the beta' relaxation that appeared at around 40 degrees C in the dynamic relaxation spectra is found to be correlated with the interfacial stress at the interface between the epoxy resin matrix and polysiloxane domain.