Orange peel waste from juicing as raw material for plastic composites intended for use in food packaging

Utilization of orange peel (OP) from the juicing industry as filler material within a polymer matrix can add value to this agricultural waste and reduce dependence on nonrenewable resources. This study aims to investigate the impact of OP filler's physical characteristics including size, loading, and retention/removal of zest on plastic properties of interest for food packaging. Linear low-density polyethylene (LLDPE) is selected to produce plastic composites due to its widespread use in food packaging. Eight different LLDPE/OP sheets from combinations of different OP characteristics are examined. Results show that OP particle sizes of 75-177 mu m without zest at 0.4-g loading improve thermal stability, color, dispersion, tensile strength, modulus of elasticity, and elongation at break as well as reduce air bubble formation and OP agglomerate sizes in LLDPE/OP composites. Results show a promise in utilization of OP fillers to produce a composite comparable to neat LLDPE and composites with UV-blocking properties. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48841.