Effects of maleated syndiotactic polystyrene on the morphology, mechanical properties, and crystallization behavior of syndiotactic polystyrene/polyamide 6 blends

摘要

The compatibilization of syndiotactic polystyrene (sPS)/polyamide 6 (PA-6) blends with maleic anhydride grafted syndiotactic polystyrene (sPS-g-MA) as a reactive compatibilizer was investigated. The sPS/PA-6 blends were in situ compatibilized by a reaction between the maleic anhydride (MA) of sPS-g-MA and the amine end group of PA-6. The occurrence of the chemical reaction was substantiated by the disappearance of a characteristic MA peak from the Fourier transform infrared spectrum. Morphology observations showed that the size of the dispersed PA-6 domains was significantly reduced and that the interfacial adhesion was much improved by the addition of sPS-g-MA. As a result of reactive compatibilization, the impact strengths of the sPS/PA-6 blends increased with an increase in the sPS-g-MA content. The crystallization behaviors of the blends were affected by the compatibilization effect of sPS-g-MA. A single melting peak of sPS in the noncompatibilized blend was gradually split into two peaks as the amount of the compatibilizer increased. A single crystallization peak of PA-6 in the noncompatibilized blend became two peaks with the addition of 3 wt% sPS-g-MA. The new peak was a result of the fractionation crystallization. As the amount of sPS-g-MA increased, the intensity of the new peak increased, and the original peak nearly disappeared. Finally, the crystallization peak of PA-6 disappeared with 20 wt% sPS-g-MA in the blend. (C) 2003 Wiley Periodicals, Inc. [References: 27]