POLYESTER IONOMERS IN BINARY AND COMPATIBILIZED BLENDS WITH POLY(ETHYLENE TEREPHTHALATE), POLY(BUTYLENE TEREPHTHALATE) AND NYLON 6,6

摘要

Binary blends of polyester ionomers with polar polymers have been prepared by both solution and melt-mixed methods to determine the effect of melt-processing on blend compatibility. The effect of metal-sulfonate groups and counterion type was evaluated by blending sulfonated and non-sulfonated forms of an amorphous polyester ionomer with both nylon 6,6 and poly(ethylene terephthalate). The thermal properties and phase behavior of the blends were determined by DSC and ESEM analysis, respectively. A comparison of the degree of compatibility for melt and solution blends suggests that polyester ionomers can interact with polyamides by strong specific interactions between the metal counterions and the amide functionalities. In contrast, polyester ionomers may become compatible with other polyesters by melt-phase transesterification (i.e., in situ copolymer formation). In blends of PBT with Nylon 6,6, sulfonated PET ionomers may be used as minor component additives for blend compatibilization. These compatibilized blends show synergistic improvements in mechanical properties with a significant decrease in minor phase domain size.