direct compatibilization of ps/epdm/pa6 ternary polymer blends through epdm-g-gma: effect of comonomer content on the morphology and properties

In this study, ethylene-propylene-diene terpolymer (epdm) and polyamide6 (pa6) were used to improve the toughness while maintaining tensile modulus of polystyrene (ps) as a general purpose polymer widely used in several industrial applications. the effect of the direct injection of gma (glycidyl methacrylate) as a functionalizing monomer on the morphology and properties ps/epdm/pa6blends was investigated. ps/epdm/pa6 ternary blends containing gma monomer and dcp (dicumylperoxide) initiator were prepared by a batch internal mixer at 120 rpm and 220 ºc. atr-ftir (attenuated total reflection- fourier transform infrared) results confirmed the grafting reaction of gma functionalizing monomer on the polymer backbone and the epoxy-amine compatibilizing reaction. sem micrographs of all studied ternary blends showed to change the type of morphology from separated dispersed to partial core-shell morphology. the finest morphology was achieved at 10 wt.% epdm-g-gma (t10-c). the results of tensile test showed a valley shape for tensile modulus (min at t10-c 1835±25 mpa and a hill shape for yielding stress (max at t10-c 27.2±0.6 mpa). this behavior can be attributed to an increasing interfacial adhesion in low content of compatibilizer (up to 10 wt.%) and appearing a coarse morphology in high content of compatibilizer (up to 15 wt.%) because of coalescence phenomenon in the rubber phase. an impact test showed a hill shape (max t10-c 32.7±0.7 j/m). a sudden fall of impact strength in high content of compatibilizer (t15-c) can be due to stress concentration on the large dispersed particles. finally, it can be claimed that the ternary blend containing 10 wt.% (t10-c) appeared the most balanced mechanical properties and the finest morphology.