Uniaxial Stretching of Biodegradable Poly(Butylene Succinate-Co-Adipate) Films Filled With Silane-Treated Wollastonite: Processing and Performance Evaluation

With the increase in public awareness about climate change, research on bioplastic packaging films has intensified. This research aims to enhance the performance of bio-based Polybutylene succinate-co-adipate (BioPBSA) and silane-treated wollastonite (S-t-WS) films using the uniaxial stretching process. The composite films are prepared by adding 15 and 25 wt.% S-t-WS followed by uniaxial stretching at stretch ratio (SR) 2.5 and 3.5. The mechanical properties, such as tensile strength and Young's modulus of the films, increase considerably after stretching, with maximum improvements of approximately 213% and 25%, respectively, compared to their unstretched counterparts. The XRD and DSC analysis show that the % crystallinity of the films increases with uniaxial stretching. This is because of the strain-induced crystallization phenomenon, which enhances the mechanical properties. The morphology of the stretched and unstretched films reveals better filler dispersion in the 15 wt.% filled films compared to the 25 wt.% ones. The water vapor barrier performance of BioPBSA/15S-t-WS improves by 12% compared to its unstretched counterpart. Moreover, the water contact angle of all the film samples is also tested. Therefore, this first-ever study on uniaxially stretched BioPBSA/S-t-WS-based films at different SRs serves as a significant scientific contribution to developing robust biodegradable films for packaging applications.