Microcellular foams from PEEK/PEI miscible blends

Blends based on the semicrystalline Poly(ether ether ketone) - PEEK and the amorphous Poly(ether imide) - PEI have been widely investigated for their outstanding mechanical, thermal and chemical-physical properties. The conformation of the PEI monomer affects the miscibility of the blends. Although the large interest in high demanding lightweight applications, foams from PEEK/PEI blend have not been considered until recently. The aim of this work was to prepare foams from PEEK/PEI miscible blends by using supercritical carbon dioxide. The role of blend composition on the density and the morphological parameters of the resulting foams was investigated.