Recycling of polypropylene/montmorillonite nanocomposites by pyrolysis

The recycling of polymer/montmorillonite (MMT) nanocomposites, upon the end of their life cycle, has attracted so far less attention than its production. In this work, polypropylene/organophilized montmorillonite (PP/OMMT) nanocomposites were prepared by melt blending and then pyrolysed to produce pyrolysed filler which can be useful to fabricate new composites. XRD and SEM methods were employed to investigate the structure and morphology of the PP materials, as well as the pyrolysed OMMT. We show that OMMT, a thermal cracking catalyst, influences pyrolysis products distribution, promoting formation of light hydrocarbons instead of wax-like olefins. The pyrolysate obtained has been confirmed to be re-usable as filler in PP composites which showed mechanical properties similar to nanocomposites containing pristine montmorillonite.