Preparation and characterization of cellulose-reinforced PLA/PHA compounds

Polylactic acid (PLA) shows high potential for various fields such as food packaging and biomedical applications due to its biodegradability and low toxicity. However, the shortcomings including brittleness and low thermal stability limit its real applications. In this study, we fabricated PLA/polyhydroxyalkanoate (PHA) compound to overcome the brittleness of PLA. Then we investigated the effects of cellulose, derived from paper waste, on the thermal and mechanical properties of PLA/PHA compounds. While cellulose negligibly affected the glass transition temperatures of PLA and PHA, the cold crystallization temperature of PLA was reduced and its degree of crystallization was increased, after the addition of cellulose. With the increase of cellulose contents, the reduced tensile strength, the increased elastic modulus, and the reduced elongation at break of the compounds were observed, attributing to the aggregation formation of cellulose. Heat deflection temperature of the compounds was raised after the addition of cellulose.