Biodegradable blends of stereocomplex polylactide and lignin by supercritical carbon dioxide-solvent system

Abstract

The development of biomaterials by utilizing natural resources attracted great interest due to environmental reasons. Lignin as part of biomass can be used as filler in polymer blending. The combination of stereocomplex polylactide and lignin was successfully generated through a supercritical carbon dioxide - solvent system. The solvation power of organic solvent to the polylactide and lignin is the key factor to obtain homogeneous blends. The supercritical carbon dioxide - tetrahydrofuran is the best system to generate stereocomplex polylactide - lignin blends. The thermal degradation property of polylactide based materials was improved by combining stereocomplex polylactide and lignin providing the simultaneous effects from the stereocomplex crystallites structure and the formation of char residue of lignin. The combination of fully bio-based materials is a promising candidate to replace non-degradable materials in the future.