Water stable composite coatings and membranes based on lignin nanoparticles

Lignin is a fascinating natural polyphenol with many essential functionalities as one of the three main components of trees and other renewable plant biomass. The recent years have seen increased efforts to find applications for different lignin grades in bio-based materials. This goal is important because increased use of lignin in materials contributes to energy-efficient economy and environmental protection. Due to its aromatic and natural polyphenolic structure, lignin is a source of antioxidant and UV-barrier functionalities. However, lignin is mostly used as a filler in composites, often in low concentrations. The low content of lignin used is at least partly owing to the lack of compatibility and understanding of interactions between different components. In our research, we focus on developing lignin-based environmentally friendly coatings based on green chemistry principles. We synthesize lignin nanoparticles-based composites as coatings with water resistance, UV blocking, antibacterial and biodegradability properties. In addition, we attempt to understand the fundamental properties of lignin-based hybrid materials, while improving the adhesion properties and tensile strength of the coatings. These lignin-based composites are of interest for many applications such as food packaging. Overall, our recently initiated research aims to develop new routes and fundamental understanding to enable sustainable production of functional coating materials that are beneficial to the environment.