Effect of poly (styrene-co-acrylonitrile) on β-nucleation of polypropylene filled with supported β-nucleating agent

β-Polypropylene/poly (styrene-co-acrylonitrile) blends (β-PP/AS) were prepared with PP, a novel supported β-nucleating agent (β-NA) and AS (method one) or β-nucleated PP and AS (method two). The influence of AS on the β-nucleation for β-nucleated PP has been analyzed. The results indicated that PP with high content of β-crystal was obtained by adding β-NA into PP. The DSC studies showed that AS and its content had little effect on crystallization and melting characteristics of β-nucleated PP, and the content of β-crystal calculated from WAXD is higher than 0.94 in all blends. β-PP/AS blends with high content of β-crystal were obtained easily. AS dispersed mainly into β-spherulite of PP as small spherular particles, and the integrity of β-spherulite decreases gradually with the increase of AS content. The etched experiment also proved that β-NA dispersed in the AS phase or interface between PP and AS.

► The β-PP/AS blends with high β-crystal content can easily be prepared by mixing PP, AS and β-NA or β-PP and AS.
► Addition of AS reduced slightly the crystallization temperature and the content of β-crystal of PP.
► It is proved by the POM and the etched experiment that β-NA mostly disperses in AS phase or interface between PP and AS.
► Increasing the content of AS resulted in the formation of β-PP spherulites with less perfection.