Exploiting Structural Benefit of Biobased Monomers for Sustainable Packaging Application with High Elasticity, UV-Blocking, and Biodegradability

Abstract

The rapid growth of e-commerce has led to a surge in product packaging use, increasing the demand for sustainable, high-performance heat-shrinkable films (HSFs). This study introduces poly[(butylene adipate)-co-(propylene furanoate)-co-(butylene furanoate)-co-(propylene adipate)] (PBPAF), a robust, highly elastic, UV-blocking, and biodegradable polymer, as a versatile HSF. The multifunctionality and sustainability of PBPAF stem from the unique structure of the biofuran monomer and the strategically optimized ratio of odd-numbered 1,3-propanediol to even-numbered 1,4-butanediol. Notably, PBPAF is synthesized without the need for plasticizers or external additives. By leveraging the even–odd effect to optimize the alcohol ratio, our novel PBPAF exhibits exceptional tensile strength (54 MPa) and outstanding elongation (800%). The resonant ring structure of furan imparts superior UV resistance, achieving the highest UV protection factor (rating >50) and a UV protection efficiency of 99.8%. Additionally, the recovery rate after elongation is enhanced due to the bending angle (129.4°) between the carbonyl groups of the furanoate units. Furthermore, within six months, the PBPAF film undergoes complete degradation under aerobic composting conditions. The resulting compost does not inhibit seed germination or early root development, confirming its suitability for plant growth. These findings highlight PBPAF’s potential to advance the development of multifunctional, biodegradable packaging solutions.