The study aims to develop high-barrier PET films without coatings or laminations using a continuous melt-blending approach. Here, polyethylene terephthalate (PET) is melt-blended with a liquid crystal polymer (Vectra) as well as polyglycolic acid (PGA). In some cases, compatibilizer is also used with PET/PGA and PET/Vectra blends. The scanning electron microscopy analysis reveals improved miscibility within the PET matrix upon incorporating 1 phr Joncryl ADR, enhancing interfacial adhesion and structural integrity. Adding 20 wt% Vectra and 20 wt% PGA to PET reduces oxygen permeability by 41% and 62%, respectively, compared to neat PET. Water vapor barrier properties are also improved by 15% and 41% for 20 wt% Vectra and 20% PGA, respectively. Differential scanning calorimetry studies confirm increased crystallinity of the blends, especially for PET with 20% PGA, where a 71% increase was observed in crystallinity. Moreover, tensile strength is improved by 41% for PET/ PGA blend and 25% for PET/Vectra blend. The tensile modulus is improved by 22% in both blends. Overall, these findings suggest PET blends as potential packaging materials for a longer shelf life for perishable food. This contrasts with multi-layer films, which pose recycling challenges and thus contribute to plastic waste accumulation in the environment.
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