Microwave-assisted Curing of Marine Vinyl ester Resins: Influence on the Mechanical Behaviour

Applications on many thermosets have shown that, with respect to the traditional curing cycles, the microwave-assisted curing always provides a substantial reduction in the curing time. So, it appears a valid alternative process for a faster manufacturing of composite structures in the shipbuilding industry. However, the effects of microwave on the mechanical properties of the materials have not been extensively studied. In the present paper, a comparison was made between the mechanical behaviour of a vinyl ester resin commonly used for marine applications cured naturally with one cured by microwave. An extensive series of tensile tests indicate that the microwave assisted curing could provide, in a shorter time, strength and stiffness values greater than those obtained by the cure at ambient conditions and that a long exposition to microwave radiation leads to a strength degradation of the resin.