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) rubbers (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 melt mixing (at a temperature of 180 degrees C) using IR. X-ray scattering from the relation of phase was analyzed using Pored's law and led to the values of the interface layer of the blends. With increasing content 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 calculated and the relation of Q with sigma(b) was calculated using Debye-Buech statistical theory, and the average chord length (l) was obtained by Pored's definition of blends. The morphology and structure of the blends were investigated by SEM. The phase separation of the blends was found by SALS. (C) 1997 John Wiley & Sons, Inc.