Functionalized Kraft Lignin as A Building Block for Nanoparticles

Co-author(s): Oihana Gordobil, Daniel Söderberg, Gunnar Henriksson, Olena Sevastyanova

My project investigates the assembly mechanisms of lignin nanoparticles (LNPs) from spruce and eucalyptus kraft lignin (SKL and EKL) and their application as additives in sunscreen formulations. By modifying lignin with varying alkyl chain lengths to enhance hydrophobicity, the study explores how these modifications influence LNP assembly during acetone/water solvent exchange process. Core-shell structured LNPs are obtained and hydrogen bonding, π–π interactions, and hydrophobic forces are key factors that controll the formation - hydrophobicity leads to more condensed and uniform LNP morphologies. Subsequently, these well-characterized LNPs are incorporated into oil-in-water (o/w) sunscreen emulsions. The impact of LNPs on the sunscreen’s UV-Vis absorption, color stability, overall stability, and rheological properties is assessed. The integration of LNPs into sunscreen formulations is shown to enhance UV protection, product stability, and texture, while maintaining an environmentally friendly feature.This comprehensive study not only provides insights into the controlled assembly of LNPs but also demonstrates their potential in creating sustainable, high-performance sunscreen products, contributing to the advancement of lignin-based materials in the field of renewable and eco-friendly commercial products.