Formation and development of phase morphology and structure on polystyrene blends. II. Study of phase behavior and structure character of PS/PS-g-MAH/LEPB/PcBR semimiscible system during melt blending by scanning electron microscopy

摘要

In this paper, polystyrene (PS)/poly(cis-butadiene) rubber (PcBR) blends were prepared by melt blending. Polystyrene-graft-maleic anhydride (PS-g-MAH) and linear epoxy polybutadiene (LEPB) were added to the blends to increase the compatibility. The blends were shown to be semimiscible by small-angle X-ray scattering (SAXS). The morphology of the blends was examined by partial extraction of material The form and the distribution of the phases were studied by scanning electron microscopy (SEM). The mixing process of the blends was characterized through the characteristic length, L, and the average characteristic length, L-m. The distribution of the characteristic length, L, was shown to be consistent with the log normal Gaussian distribution. The mixing system was shown to possess self-similarity in a certain range of time, as shown through a scale function. Furthermore, the fractal dimension, D, was calculated at different times and shown to be a parameter that can be used to describe the process of melt blending. The PS-g-MAH and LEPB were shown to increase the compatibility by comparison with the immiscible blend PS/PcBR.