Functionalization of polyolefins by reactive processing: influence of starting reagents on content and type of grafted groups

Previus studies carried out in our laboratory on the functionalization of ethylene polymers (homo and copolymers) through free radical processes, using mechanical mixers and/or extruders with diethylmaleate (DEM) and dicumyl peroxide (DCP), have shown that the presence of branched alfa-olefin blocks favours degradation versus functionalization and crosslinking whereas these last are more effective with linear ethylene blocks. In this contest the present paper reports about attempts to extend the same processes to propylene polymers by benefitting of the indications of previous results. In particular the one step functionalization of EPM with two or more different groups was carried through the use of different monomers. Moreover the procedure was extended to polypropylene thus obtaining a significant functionalization degree flanked by a remarkable decrease of molecular weight.