Holocellulose modified by Lauric acid and its application in biodegradable composites based on poly(butylene adipate-co-terephthalate) and polylactic acid

Holocellulose laurate (HC-L) was prepared by the esterification of holocellulose with lauric acid, and then was further melt-blended with poly(butylene adipate-co-terephthalate) (PBAT) and polylactic acid (PLA) to obtain a biodegradable HC-L/PBAT/PLA composite. Compared with those of the PBAT/PLA matrix, the comprehensive properties, including the thermal properties, water stability, gas barrier properties and degradation properties of HC-L/PBAT/PLA with 5 wt% HC-L were improved. The elongation at break and 90-d biodegradation rates increased by 64% and 11.0%, respectively. The water absorption capacity, water vapor transmission and oxygen permeability decreased by 60%, 18.6%, and 33.2%, respectively, and the water contact angle increased from 91.9 degrees to 112 degrees. The elongation at break, thermal stability, water stability and gas barrier properties of HC-L/PBAT/PLA were superior to those of a commercial bio-based pallet. The results showed that modified holocellulose can be used as a filler in biodegradable composites, expanding the utilization of lignocellulosic resources in the packaging field.