Investigation of material characteristics and processing conditions effects on bubble growth behavior in a physical foaming process

摘要

Bubble growth during polymeric foam production by a physical nucleating agent is a result of rapid gas phase separation in a polymer/gas solution media. The dynamics of bubble growth is thought to be influenced by the material properties and processing conditions. However, the degree of effectiveness of each parameter has not been evaluated in earlier studies. In this work, a simplified single bubble growth in a polymeric media was modeled to specify the critical parameters affecting the bubble growth phenomenon. The predicted bubble growth profile was compared with some experimental data reported in the literature. The model was able to predict the observed bubble growth profile with acceptable precision. Therefore, it was applied to investigate the effect of each physical property of the polymer, i.e. viscosity, surface tension and diffusion coefficient as well as processing conditions, i.e. temperature and pressure release rate on the bubble growth profile. Furthermore, the impact of each factor was clarified.