A kinetic model for free-radical crosslinking co-polymerization of styrene/vinylester resin

Vinylester resin is a major thermoset polymer used in low temperature compo site manufacturing processes, such as the Seemann Composite Resin Infusion Molding Process (SCRIMP). In this study, the effect of temperature on the c ure kinetics of a vinylester resin in the range of 35 to 90 degreesC was in vestigated using a differential scanning calorimeter (DSC) and a Fourier tr ansform infrared spectrometer (FTIR). A mechanistic kinetic model was devel oped to simulate the reaction rate and conversion profiles of vinylester vi nylene and styrene vinyl groups, as well as the total reaction rate and con version. Experimental results from DSC and FTIR at different temperatures w ere compared with model predictions. The glass transition temperature of th e vinylester resin cured at different temperatures was identified and used to monitor the final conversion change. A series of SCRIMP molding experime nts were conducted. The developed kinetic model in conjunction with a heat transfer model was used to simulate the temperature and conversion changes inside the SCRIMP-molded composites.