Polypropylene–polysilsesquioxane blends

This paper deals with the preparation of PP/polysilsesquioxane blends and their study to investigate silsesquioxane dispersion, mechanical properties, thermal stability and combustion properties by means of a number of techniques, such as SEM, XRD, Rheology, TGA, DSC, Cone Calorimeter tests and LOI. Polysilsesquioxane with different organic groups (methyl, vinyl or phenyl) were used; both dispersion and final properties were found to be dependent on the silsesquioxane organic fraction type. The PP/polysilsesquioxane blends showed an increased thermoxidative stability and combustion resistance, in terms of lower rate of heat release. Higher mechanical performances were also achieved with PP/vinyl polysilsesquioxane, with higher elastic modulus as well as higher elongation at break.