Effect of Additives on Cure Kinetics of Pultrusion Resins

Abstract

Cure kinetics of pultrusion resins differ from the kinetics of resins used in other methods of composites production due to the presence of technological additives. Such additives add useful properties to the composite, for example, reduce the friction of the composite on a die or reduce the combustibility of the composite. This work is devoted to studying the effect of additives on vinyl ester resin cure kinetics. The curing process was characterized using differential scanning calorimetry (DSC). The effects of the addition of Zinc-stearate and Aluminum-hydroxide on vinyl ether ATLAC 430 resin were analyzed with dynamic scans at different heating rates. The obtained kinetics clearly showed that additives influence the resin polymerization enthalpy. The effect of additives on the enthalpy also transferred to the obtained kinetic constants of their models. Moreover, additives can effect on the model error - this effect clearly demonstrates the melting of zinc stearate, which is superimposed on the final polymerization stage of the studied resin. Results show that the calculation of kinetics in industrial production should be carried out considering all the technological additives to optimize the process and to obtain a large number of high-quality pultrusion profiles. Also, the results clearly show that there is a need to further study the effect of additives on the kinetics of polymerization of pultruded resins.