Effect of kraft lignin and esterified lignin on the properties of thermoplastic starch

► Kraft lignin (KL) and esterified lignin (EL) were used as fillers for the TPS matrix. ► EL was produced via esterification of the KL hydroxyl groups. ► The tensile strength of TPS/EL composite is higher than for the TPS/KL composite. ► Lignin obstructed the penetration of water into the TPS.