Reactive blending of functionalized polypropylene and polyamide 6: In situ polymerization and in situ compatibilization

Abstract Compatibilized polypropylene/polyamide 6 blends were prepared with polypropylene, ε‐caprolactam and maleic anhydride grafted polypropylene via in situ polymerization and in situ compatibilization in a batch mixer. Scanning electron microscopy and differential scanning calorimetric analysis showed that the compatibilizing effect was significantly enhanced through use of this method compared to the classic method of blending premade polymers. The optimum processing parameters were obtained for the reactive blends and the effect of maleic anhydride grafted polypropylene content, and the effect of relative weight fraction of maleic anhydride grafted polypropylene to ε‐caprolactam on the overall morphology of the blend system was investigated. It was found that the domain sizes of the polypropylene and polyamide components in the blends could be easily controlled through proper management of the polymerization and compatibilizing reactions during processing. Polym. Eng. Sci. 44:648–659, 2004. © 2004 Society of Plastics Engineers.