Aqueous Dispersions of Esterified Lignin Particles for Hydrophobic Coatings

摘要: An aqueous biopolymer dispersion coating system was synthesized utilizing softwood kraft lignin and a long chain organic acid. The chemical treatment of two-step procedure, which first consisted hydroxyethylation the phenolic groups on ethylene carbonate an alkaline catalyst. This step resulted in containing more than 80% aliphatic hydroxyl functionality (1H NMR). Following this step, oleic acid reacted with hydoxyethyl order to form ester derivatives. With nearly total reduction absorbance stretching region, FT-IR analysis showed majority esterified forming ethyl oleate derivative. Semi-quantitative 13C NMR revealed 88% substitution groups. derivative soluble solvent such as toluene tetrahydrofuran. Solutions derivatives were slowly precipitated through dialysis, resulting stable microparticles distilled water. 1-2 μm average diameter size particles found dynamic light scattering suspensions. Spray spin used apply different surfaces. For both methods, lignin-based enhanced hydrophobicity all substrates tested, increased water contact angles for glass, pulp sheets solid wood. Benign reagents involved synthesis utilized natural compounds that are known repel nature. Combined avoidance volatile solvents during application, process provided low environmental footprint solution hydrophobic coatings.