Preparation and Characterization of Electrospun Films of Poly (3- hydroxybutyrate-co-3-hydroxyvalerate) Derived From Fruit Pulp Biowaste for Food Biopackaging

Abstract

Industrial by-product residues management is the main goal to maintain resource conservation and the quality of the environment. The growing concern for plastic waste disposal of petroleum-based materials has intensified the study and development of bio-based and biodegradable polymers, particularly those synthesized from agro-industrial residues [1]. Recently, biopolymers are used to replace petroleum-based synthetic polymers to reduce the non-renewable energy consumption and the carbon dioxide emission [2]. This work reports different methods to purify, namely non-extraction, extraction with sodium hypochlorite (NaClO) (sample 1), and extraction with chloroform (sample 2) of a circular economy based and potentially low-cost poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) produced by mixed microbial cultures derived from fruit pulp, an industrial by-product of the juice industry. The highest yield obtained was 40% with sample 2 and it was the most optimal solution for its processing via electrospinning. After thermal post-processed of the resultant ultrathin fiber mats, in order to obtain continuous films adequate for food packaging applications, the films were characterized in terms of morphology, crystallinity as well as thermal, mechanical, and barrier properties. Different results in their characteristics were found depending on the purification applied. The results showed that sample 2 presented the highest degree of purity, resulting in more transparent films with lower wettability and higher flexibility. Therefore, there are a great potential as interlayers or coatings for food biopackaging applications for these electrospun films made of biomass derived from biowaste [3].