A predictive method for estimating the minimum dynamic critical system pressure required to disperse the blowing agents in molten polystyrene has been introduced based on the relationship between dynamic and equilibrium solubility determined using the Theory of Corresponding States. This method can be used to estimate the minimum dynamic system pressure required to disperse new blowing agent systems as a function of temperature and blowing agent concentration in the foam extrusion line. A brief discussion on the effect of dynamic system pressure on the cellular structure, skin, quality, and the pressure drop calculations through the foam extrusion line will be given.
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