Blends of polyamide 6 and epichlorohydrin elastomers. I. Graft copolymerization in the melt blending

With the purpose of improving the mechanical properties of the polyamides, the possibility of combining polyamides with elastomers has been used. The low compatibility of the resulting blends leads to deficient mechanical pro perties, and therefore, it is necessary to add the compatibilizer to the mi xture or to produce the compatibilizer during the melting mixture. Usually, at least one of the components must contain a reactive functional groups. In the present work, blends of polyamide 6 (PA 6) and epichlorohydrin elast omers, polyepichlorohydrin (PEPI), and the equimolar copolymer poly(epichlo rohydrin-co-ethylene oxide), EGO, with different compositions were prepared by mechanical mixture using a Banbury-type mixer. The blends were characte rized by rheological measurements, the Molau test, elemental analysis, Infr ared Spectroscopy by Diffuse Reflectance, Transmission Electron Microscopy, and X-ray Diffractometry. The blends of PA 6 with PEPI and ECO are heterog eneous, showing a morphology of elastomer particles dispersed in the polyam ide matrix. The results of rheological measurements and the Molau test indi cate a graft copolymerization in the interface between the polyamide and th e elastomer, PA 6-g-elastomer, whose concentration decreases with the elast omer content. It was found that the grafting of PEPI and PA 6 changed the d iffraction pattern of PA 6. (C) 1999 John Wiley & Sons, Inc. J Appl Polym S ci 72: 1827-1833, 1999.