Investigation of the structure of isotactic polypropylene—thermoplastic elastomer blends by means of X-ray scattering

Blends of semicrystalline isotactic polypropylene (iPP) with two types of elastomer, butadiene/styrene (BS) and hydrogenated isoprene/styrene (HIS), block copolymers were investigated by means of wide-angle and small-angle X-ray scattering. Except for the sample with a low concentration of BS (5 wt%), where the copolymer macromolecules are probably dispersed in the amorphous phase of iPP, the blends can be described as two-component systems (copolymer-iPP), in which the crystalline phase of iPP is only slightly influenced by the copolymer. X-ray results in the structural investigation of the blends correlate well with the mechanical properties of the blends.