Influence of comonomer incorporation on morphology and thermal and mechanical properties of blends based upon isotactic metallocene–polypropene and random ethene/1‐butene copolymers

Blends of isotactic polypropene (i‐PP) with random ethene/1‐butene (EB) copolymers containing 10, 24, 48, 58, 62, 82, and 90 wt % 1‐butene were prepared in order to examine the influence of the EB molecular architecture on the morphology development as well as on the thermal and mechanical properties. Compatibility between i‐PP and EB increased with increasing 1‐butene content in EB to afford single‐phase blends at a 1‐butene content exceeding 82 wt %. The morphology was investigated using AFM and TEM. Improved compatibility accounted for enhanced EB dispersion and interfacial adhesion. Highly flexible as well as stiff blends with improved toughness were obtained. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 838–848, 1999