Biodegradable electrospun bionanocomposite fibers based on plasticized PLA–PHB blends reinforced with cellulose nanocrystals

Electrospun biobased and biodegradable nanocomposites for sustainable flexible films were developed. Poly(lactic acid) (PLA) was blended with 25 wt% of poly(hydroxybutyrate) (PHB) to produce bead-less fibers and plasticized with 15 wt% of acetyl(tributyl citrate) (ATBC) to obtain flexible materials. The system was further loaded with cellulose nanocrystals (CNC) in 1 wt% and 5 wt% to obtain bionanocomposites with improved thermal and mechanical resistance. The morphological, structural, thermal and mechanical performance of electrospun bionanocomposites was investigated. The effect of ATBC was characterized by a decrease of the glass transition temperature and an increase in the elongation at break. Meanwhile, CNC improved the thermal and mechanical resistance of mats. Thus, good performance for the intended use was achieved for the bionanocomposite loaded with 1 wt% of CNC (PLA–PHB–ATBC–CNC1), which also showed appropriate surface water resistance. All electrospun bionanocomposites were fully disintegrated under composting conditions showing their possible applications as compostable flexible film materials.