Effects of Nucleating Agent on Polymeric Microcellular Foaming

Foamed plastics are used extensively throughout the world. Compared with solid plastic products, plastic foams with high cell density and uniform cell sizes have superior mechanicalproperties, including toughness, impact strength and improved thermal insulation [1-3]. Addition of nanoparticle has asignificant effect on the final foam structure. Several parameters of nanoparticle such as size, shape, content, and distribution of nanoparticle can change the final foam tructure[4-6]. In this study we will first theoretically descibed the effect of nanosilica and nanosilica content on the cell densityof foam. It is reasonable to think that the increasing effect of nanosilica on the cell density of the final cellular structure isdue to their contribution to the nucleation phenomenon. In other words, the existence of nanosilica emphasizes phase separation via the nucleation of gas bubbles. We use classical nucleation theory for homogeneous nucleation and improve it for non-homogenous nucleation.