Wollastonite-reinforced polypropylene composites modified with novel metallocene EPR copolymers. I. Phase structure and morphology

Supermolecular structure of isotactic polypropylene/wollastonite/metallocene propylene–ethylene copolymers (iPP/W/EPR) composites was studied as a function of elastomer content (from 0 to 20 vol%) by optical, scanning, and transmission electron microscopy, wide‐angle X‐ray diffraction, and differential scanning calorimetry. Both, wollastonite and dispersed EPR particles, homogeneously incorporated into the iPP matrix, and affected the final phase structure and morphology of the iPP/wollastonite/EPR composites. Wollastonite particles were orientated plane‐parallel to the sample surface and hindered spherulite growth of the iPP matrix. EPRs enhanced plane‐parallel orientation of wollastonite and simultaneously enhanced the spherulite and crystallite growth in the iPP matrix during the solidification of polymer melt. Ternary iPP/wollastonite/EPR composites exhibited significant prevalence of separated microphase morphology (over core‐shell morphology) because of constitution similarity of P‐E and iPP chains. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers.