Effect of structure of functionalizing molecules on the inter-macromolecular reactions and blending of poly(ethylene-co-propylene) (EPM) with poly(6-aminohexanoic acid) (PA6)

Two different functionalizing systems, i.e., monohexadecyl maleate (=hexadecyl hydrogen (2Z)-but-2-enedioate) in the presence of dicumyl peroxide (=bis(1-methyl-1-phenylethyl) peroxide) or 4-carboxybenzenesulfonazide (=4-(azidosulfonyl)benzoic acid), were used in distinct experiments to perform in a one-step procedure the formation of a EPM-PA6 graft copolymer, necessary to obtain a compatibilized blend, from a molten mixture of ethylene-propylene copolymer (EPM) and polyamide 6 (PA6). The characterization of the graft polymer by selective solvent extraction of the blends and the subsequent IR and NMR analysis of the various fractions established the occurrence of functionalization reactions preferentially onto the polyolefin with both reagents. Also the formation in good yield of graft copolymers at the phases interface was observed. Moreover, the morphology and thermal characterizations of the blends by means of SEM and DSC analyses were used to evaluate the compatibilization extent in comparison with blends obtained by the conventional two-step procedure or by the one-step procedure with commercial maleic acid derivatives.