Abstract:
This aim of this study was investigate the effect of the multifunctional epoxy-containing oligomer Elvaloy PTW, in combination with the zinc ionomer Surlyn on chemical modification of low melt strength thermoplastic poly(ethylene terephthalate) (PET) and thermoplastic elastomer Hytrel®. In PET, the low melt strength characteristic limits the material’s performance and reduces the number of times PET can be recycled and reprocessed. Thus, studies were conducted on improvements of molar mass/molecular weight, to compensate the loss. Preparation of PET modification (mA12) were made in accordance with Plimmer and Tanner’s study on PLA modification. Results showed increased changes in torque in the Brabender mixer attributed to the addition of the reactants. Confirmation of the structure of resulting polymer by FTIR spectrum through the reaction of the epoxy group of Elvaloy PTW and PET terminal group. Viscosity was measured through melt flow index and viscosity test, and calculation of molecular weight were made based on the intrinsic viscosity values. Compatibleness of Surlyn and Elvaloy in the blends was evaluated through DSC, TGA, and SEM, and all results evidenced achievement of the compounded mA12. Hytrel blends were prepared by varying the amount of Hytrel® 3078 (50% and 75%) and the ratio of Surlyn 9020/Elvaloy PTW reactant with increasing amounts of Surlyn percentage (1:1, 2:1, 3:1, and 4:1). Success was observed through Brabender mixer, FTIR, DMA, TGA and SEM, showing increased reactivity of the carboxylate anions of Hytrel® with the epoxide end groups of Elvaloy PTW by formation of more crosslinks. However, opposing results were shown in DSC, DMA and tensile tests, with unchanged crystallisation and melting temperature, as well as reduced tensile strength.