Compatibilized low-density polyethylene/linear low-density polyethylene/nanoclay nanocomposites: II. Opposing effects of nanofiller on quiescent and shear-induced crystallization

Isothermal and non-isothermal crystallization processes of polyolefin nanocomposites based on low-density polyethylene/linear low-density polyethylene/nanoclay have been investigated, and the effects of nanoclay loading and dispersion state have been studied. Moreover, the isothermal crystallization of polyethylene chains has been evaluated in the quiescent and shear-induced conditions. In quiescent crystallization, adding 1wt% nanofiller improves the crystallization rate, whereas an increment in the organoclay loading retards the crystallization process. However, an opposing effect of nanoparticles is observed in the shear-induced crystallization. The findings show that the incorporation of 5wt% nanoclay in good dispersion state considerably accelerates the shear-induced crystallization process. This influence is found even for very weak shear flow fields. The synergistic effects of nanoclay addition and shear field presence on the crystallization process are of major significance particularly for polyolefin products, which are commonly manufactured by using melt processing methods.