BLENDS OF POLYPROPYLENE WITH POLY(CIS-BUTADIENE) RUBBER .1. PHASE-STRUCTURE AND MORPHOLOGY OF BLENDS

Pressed films of blends of polypropylene with poly(cis-butadiene) rubb ers (PcBR) or grafted copolymer of ethyl acrylate (EA) onto PcBR (PcBR -g-EA) was examined by IR spectra, small angle X-ray scattering, small angle laser scattering (SALS), and scanning election microscopy (SEM) . The problem of isomerization on PcBR (or PP/PcBR) is discussed by me lt mixing (at a temperature of 180 degrees C) using IR. X-ray scatteri ng from the relation of phase was analyzed using Pored's law and led t o the values of the interface layer of the blends. With increasing con tent of rubber, the interface layer thickness (sigma(b)) had a maximum value at 60/40 (PP/PcBR-g-EA) for the blends. The invariant (Q) was c alculated and the relation of Q with sigma(b) was calculated using Deb ye-Buech statistical theory, and the average chord length (l) was obta ined by Pored's definition of blends. The morphology and structure of the blends were investigated by SEM. The phase separation of the blend s was found by SALS. (C) 1997 John Wiley & Sons, Inc.