Blends of polypropylene with poly(cis-butadiene) rubber. III. Study on the phase structure and morphology of incompatible blends of polypropylene with poly(cis-butadiene) rubber

Scanning electron microscopy (SEM) was used to study the structure and morphology of partly compatible binary blends of polypropylene with poly(cis-butadiene) rubber. The SEM images were transformed by digital image process software designed by our group, and binarized images were obtained. The size (mean diameters d_p and characteristic lengths L) of phases was calculated using binarized images. Small-angle light scattering was employed to study the structure and morphology of phases in the blends. The structural parameters, including correlation distance a_c, average chord lengths l, and mean diameter D_S to describe the structure and morphology of phases in binary blends, were calculated based on the corresponding theory. The variation of correlation distance a_c, average chord length l, and mean diameter D_S were the same as that of mean diameters d_p and characteristic length L. At the same time, the distribution of sizes of the dispersed phase in binary blends was calculated with graph transition technique, which possessed log-normal distribution characterization. The power spectrum images corresponding to small-angle light scattering images were obtained by two-dimensional fourier transformation of binary images. The correlation distances a_cf and average chord length l_f have been calculated by intensity of power spectrum images and that was the same as a_c and l. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4900–4909, 2006