Biodegradable blown film composite from poly (butylene adipate-co-terephthalate) and talc: Effect of uniaxial stretching on mechanical and barrier properties

This research focuses on improving the oxygen and water vapour barrier properties of blown PBAT films after adding talc particles (15 and 25 wt%) followed by uniaxial stretching in the machine direction. DSC analysis revealed that the addition of talc enhanced %crystallinity by ∼42 and ∼125% at stretch ratios 5.5 and 6.0, respectively, compared to unstretched neat PBAT films, due to the dispersion and platelets morphology of talc particles, followed by uniaxial orientation of polymer chains. This significantly impacted the mechanical properties of PBAT as elastic modulus gained by ∼1939 and ∼2486% for the stretched composite films containing 15 and 25 wt% talc, respectively, over unstretched neat PBAT. The water vapour barrier of the stretched composite films was improved by ∼61 and ∼62% after adding 15 and 25 wt% talc particles, respectively, compared to PBAT due to its increased %crystallinity and can be a sustainable alternative to single-use plastics in flexible packaging.