Dynamic and mechanical properties of vinyl ester/epoxy interpenetrating polymer networks

A series of vinyl ester (VE)/epoxy (EP) interpenetrating polymer networks (IPNs) were prepared by a simultaneous method. The change in characteristic groups, curing process, mechanical properties, damping properties, morphology, and thermal stability was studied. It was found that the damping ability, mechanical properties, and thermal stability were all enhanced through the introduction of VE into EP to form the IPN structure. Result of the dynamic mechanical analysis showed that glass transition temperature decreased and the tanδ peak shifted to a lower temperature with increased EP content in IPNs. Mechanical measurement revealed that the impact strength of the IPNs was higher than that of the EP matrix, and the tensile strength of the IPNs was impaired when the VE content was beyond 10%. Morphological investigation also proved that the brittle behavior was improved.