Thin Films from Acetylated Lignin

Lignin is a highly abundant biopolymer, however, the varying sources and complexity in composition make the utilization challenging. The solubility and reactivity of lignin can be strongly affected by chemical modification such as acetylation, making it available to various additional applications. Acetylation can be achieved by a microwave assisted reaction with acetanhydride. The obtained acetylated lignin (AcL) was further used to prepare thin films by spin coating with tuneable thicknesses in the nanometer range depending on the AcL concentration. The films were characterized by different surface sensitive techniques, such as contact angle determination, ATR-IR spectroscopy, atomic force microscopy and profilometry. The preparation of defined thin films from acetylated lignin forms a good foundation for further research, especially in the field of nanostructured biomacromolecules.