The Foaming Process of Biodegradable Polyesters

摘要

PCL and PCL/nanoclay foams were obtained by using CO_2 and/or N_2 as foaming agents. The different solubility and diffusivity of the two gases leaded to different morphology, in terms of foam density and cell size. The most interesting cellular morphology, characterized by a low-density microcellular structure, was obtained when a mixture of the two gases was employed. The presence of nanoclays led to materials with different thermal and rheological properties that affected nucleation and growth phenomena of gas bubbles. Compared to PCL foams, the cellular structure of nanocomposites was characterized by a higher density of lower size cells.