On the Effect of E-Glass Fiber on the Cure Behavior of Vinylester Composites

The effects of fiber loading level and cure temperature on the cure kinetics of an E-glass/vinylester composite are investigated using DSC techniques. It is shown that for the specific system under consideration the presence of the fibers significantly inhibits final cure levels with activation energy levels decreasing with increasing fiber loading. Autocatalytic rate parameters, k and m, are also shown to increase with fiber loading level. The loading level of the E-glass reinforcement is shown in specific instances to have a more significant effect than a change in cure temperature emphasizing the importance of characterizing cure based on actual resin-fiber-sizing systems rather than simply on the basis of neat resin cure kinetics. Results are viewed in terms of the specifics of the polymerization process and the implications on the use of processes such as resin infusion with vinylesters for the fabrication of large structural components are discussed.