139c Solubility and Spinodal Decomposition Analysis for Thermoplastic Foams

Chien-Yueh Huang and Lining Zhu. Chemical Engineering, New Jersey Institute of Technology, Newark, NJ 07102

Using Sanchez-Lacombe Theory, we calculated the solubility and spinodal surfaces for solutions of inert gases dissolving in thermoplastics. The gas solubility surfaces are compared to known experimental data and can be used for simulating the kinetic path of foaming on the pressure-temperature plane in batch or continuous extrusion processes. Relations of experimental data of cell density and the pressure superheat are studied and are compared with the classic nucleation theory. A critical superheat surface is suggested for explaining the gap between theoretically predicted and experimental measured nucleation rates.