engleski

Effect of the Filler on The Curing Kinetics of an Unsaturated Polyester Resin

The effects of the filler (calcium carbonate) on the curing kinetics of an unsaturated polyester resin were studied by differential scanning calorimetry (DSC). Methyl ethyl ketone peroxide (MEKP) was used as initiator. DSC experiments were performed both in dynamic conditions at different heating rates and in isothermal conditions at different temperatures ranging from 100 to 120oC. For all the systems investigated, a second (dynamic) scan on the isothermally cured samples indicated that the curing reaction was completed at any of the temperatures applied. In general, the addition of the filler results in an increase of the cure reaction time. At a constant heating rate the reaction is characterized by lower onset temperature and lower reaction rate with respect to the neat resin. An autocatalytic kinetic model was applied to isothermal DSC data. The rate constants have the usual Arrhenius form and the activation energy values, Ea, are in agreement with those tabulated in the literature. For the systems containing the filler higher values of Ea were obtained in comparison with the neat resin. The kinetic model with parameters determined from isothermal DSC data was successfully applied to dynamic DSC data over a broad temperature range that covers usual processing conditions.

nije evidentirano

nije evidentirano