The role of hydrophilic organoclay in morphology development of poly(butylene terephthalate)/polypropylene blends

Abstract

This work is concerned with the effect of hydrophilic organoclay on morphology development of poly(butylene terephthalate) (PBT)/polypropylene (PP) blends. The concentration of nanoclays is varied from 1, 3, and 5 phr of polymer blend. Morphological analysis of nanocomposites shows a pronounced refinement of phase morphology with the reduction of droplet size, as compared to neat PBT/PP blend. With the aid of transmission electron microscopy, X-ray diffractometry, and rheological measurements, it is found that organoclays are exclusively located in PBT matrix and at the interface. The nonhomogeneous distribution of organoclays at the interface results in coalescence suppression of droplets and reduction of interfacial tension. Moreover, viscosity and elasticity of matrix are increased with the confinement of organoclays in PBT, which ends up with easier breakup of droplets. According to our research, using nanoclay changes the elasticity ratio of phases that affects capillary number and morphology of the blend. Our calculation indicates that the minimum size of dispersed droplets occurs at elasticity ratio of 1.92.