Photo-curing modelling: direct irradiation

Abstract

Thermosetting resins are converted into three-dimensional networks via a polymerisation reaction known as cure. This reaction determines the resin morphology that, in turn, will determine the physical, electrical, and mechanical properties of the cured material. Moreover, the cure reaction of thermosets is exothermic and polymers exhibit low thermal conductivity so the temperature and rate of reaction can vary considerably within the curing mass. Simulations of the behaviour of these materials require analytical models accurately describing its cure kinetics. An integrated thermal-kinetic model is presented to study photo-initiated curing reactions and determine different aspects associated with these reactions, describing both the heat transfer phenomenon all along the reaction and the cure kinetics. This model is sensitive to the resin composition, temperature and light intensity, apart from describing the main events occurring during cure reactions. The kinetic model and the law of the conservation of energy are coupled, while the integrated model is numerically solved.