Sustainable Bio-Composites Obtained from Recycling Post-Industrial PLA and Fillers Derived from Coffee Production

Abstract

Bio-composites have been formulated by exploiting post-industrial PLA derived from thin film production and silver skin, a by-product of the coffee’s roasting process. The mix design for the compounds exploits the effects of regrading and toughening agents. The mechanical properties of the materials have been investigated as well as the thermal and physical ones. The recycled material mixed with the regrading additive shows good mechanical properties. The filler addition increases the elastic modulus of PLA up to a 20% but decreases the mechanical properties (about 20% on tensile strength), leading to a brittle behavior (minus 35% of impact strength). The use of a toughening agent restores the plastic deformation ability of the matrix.