A mathematical model for estimating in-production life of catalyzed epoxy systems used in vacuum pressure impregnation processing

A mathematical model has been devised for estimating in-production life of VPI resin systems. It is based on assuming that the viscosity changes with time according to a simple exponential function, that the components contribute to the viscosity of the mixture independently of one another and that a simple additivity rule is valid for logarithms of viscosity. The only parameters concerning the VPI facility are replenishment rate and the maximum acceptable viscosity. All the information concerning the resin systems behaving linearly which is necessary for these computations can be obtained in a matter of days. With non-linear systems, the measurements have to be carried to significantly longer periods of time.