COMPATIBILITY OF BLENDS OF POLY(ETHYLENE-TEREPHTHALATE) WITH THE IONOMER OF ETHYLENE METHACRYLIC-ACID COPOLYMER

The compatibility behaviour of melt-mixed blends of poly(ethylene tere phthalate) (PET) with the sodium ionomer of poly(ethylene-co-methacryl ic acid) were investigated in the complete composition range. The tech niques used were dynamic mechanical analysis (DMA), DSC, tensile prope rties, optical and electronic microscopy. DMA indicated a non-miscible blend except at the high ionomer contents. Tensile properties were go od indications of mechanical compatibility resulting from good compone nt adhesion. Considerable interaction was also revealed from the T(m) depression of the two crystalline blend components and the composition dependence of blend crystallinity. Morphology examination with SEM co rroborated these findings. On the basis of preliminary tensile testing , it is also demonstrated that the ionomer may be used as an effective compatibilizer for PET/LLDPE.