Simulation study of engineered Integral-Layer with Solid-Skin structure in Microcellular Polystyrene Foam using Superheat-Induced-Foaming method

Abstract

Abstract Microcellular plastic foam can be formed by the so-called superheat-induced-foaming method, which known as solid-state foaming process. This process involves the dissolution of the blowing agent (CO2) in polystyrene and foaming the gas-laden polystyrene by induction the superheat on it. This process utilizes the effect of plasticization due to dissolved blowing agent in polystyrene matrices. An interval time which desorption of CO2 occurs, definitely after dissolution CO2 in polystyrene prior the foaming process, would make it is possible to develop the integral layer which consists of transition-cellular-core and solid-skin layer by manipulating the desorption time. In the present study, the solid-skin and integral-core-layer formation is simulated by considering the heat and mass transfer model to predict the solid-skin thickness and classical nucleation theory to predict the amount of cell density. It is concluded that with an increase of desorption time, the solid-skin is thicker, and the cell density is lower, compared with the lower desorption time, thinner solid-skin is obtained. Whereas, an increase in foaming temperature, thinner solid-skin with higher cell density is predicted contrary with lower foaming temperature. Additionally, in this study, the predicted cell nucleation is validated to the experimental results with sum-squared-error about 7.248.