Synthesis and mechanical properties of thermoplastic films from lignin, sebacic acid and poly(ethylene glycol)

• Production of soda lignin-based thermoplastic and biodegradable film.
• The breaking elongation of soda lignin-based film reached 68%.
• The film obtained by hot compressing conditioning at 110 °C without odor.

Lignin-based thermoplastic copolyester was synthesized via copolymerization of sebacoyl dichloride with alkali lignin and poly(ethylene glycol). The copolymers obtained were thermo pressed into films. Lignin from paper making industry is abundantly available, renewable, and inexpensive but its applications are limited owing to its complicated structure. We aim to prepare a thermo-stable and thermoplastic lignin-based material. The effects of reaction conditions on weight gains and the effect of COCl/OH ratio on tensile properties of the copolymer films were studied. The reaction of the hydroxyl groups with sebacoyl dichloride was verified by FTIR and 1H NMR. Films obtained demonstrated good thermal properties and toughness.