inhibition effect of polyvinyl butyral on crystallization of polypropylene

In this work, a series of polypropylene/polyvinyl butyral (pp/pvb) blends were prepared by melt-blending process, at pvb loadings 3 wt%, 10 wt%, and 30 wt%. the effects of pvb on crystallization behavior of pp were investigated by differential scanning calorimetry (dsc), and polarized optical microscopy (pom). the isothermal crystallization kinetics were analyzed by avrami equations. it was found that the addition of pvb strikingly reduced the overall crystallization rate of pp. the pom results further indicated that the crystallization rate of pp/ pvb was significantly reduced by reducing the nucleation density of pp with the addition of pvb. the fractured surface morphology of pp/pvb blends was characterized by scanning electron microscopy (sem), and the results showed that the pvb was uniformly dispersed in the pp matrix as small spherical particles, with a good dispersion and dimensional stability.