Abstract
One technique of the control method for foams that have required internal structure was investigated, clarifying quantitatively effects of control factors on cell size and cell density and evaluating the characteristics of those factors. The following results were obtained. Equivalency is maintained between the foaming time and foaming temperature dependence of the cell density of foamed PC, and one master curve is obtained for the cell density. That is, the time-temperature equivalent law is held about cell density. Based on the time-temperature equivalent law, the control method, which can be predicted the required foaming conditions of plastics having arbitrary cell densities was proposed. Using above method, it is possible to predict the required foaming conditions of plastics having required cell densities.
