Nonisothermal Crystallization and Melting Behavior of β-Nucleated Isotactic Polypropylene and Polyamide 66 Blends

A highly novel nano-CaCO3 supported beta-nucleating agent was employed to prepare beta-nucleated isotactic polypropylene (iPP) blend with polyamide (PA) 66, beta-nucleated iPP/PA66 blend, as well as its compatibilized version with maleic anhydride grafted PP (PP-g-MA), maleic anhydride grafted polyethylene-octene (POE-g-MA), and polyethylene-vinyl acetate (EVA-g-MA), respectively. Nonisothermal crystallization behavior and melting characteristics of beta-nucleated iPP and its blends were investigated by differential scanning calorimeter and wide angle X-ray diffraction. Experimental results indicated that the crystallization temperature (T-c(p)) of PP shifts to high temperature in the non-nucleated PP/PA66 blends because of the alpha-nucleating effect of PA66. T-c(p) of PP and the beta-crystal content (K-beta) in beta-nucleated iPP/PA66 blends not only depended on the PA66 content, but also on the compatibilizer type. Addition of PP-g-MA and POE-g-MA into beta-nucleated iPP/PA66 blends increased the beta-crystal content; however, EVA-g-MA is not benefit for the formation of beta-crystal in the compatibilized beta-nucleated iPP/PA66 blend. It can be relative to the different interfacial interactions between PP and compatibilizers. The nonisothermal crystallization kinetics of PP in the blends was evaluated by Mo's method. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 3566-3573, 2011