Lignin based Sustainable Hydrophobic Coatings

Date: 18 July 2019

Country: Canada

Application

• Water-Repellent Coatings: Enhances hydrophobicity of wood-based materials, improving moisture resistance for construction and packaging applications.
• Sustainable Protective Coatings: Utilizes renewable lignin-based materials for eco-friendly coatings in various industries, reducing reliance on toxic solvents.

Description

This project focuses on creating hydrophobic coatings using esterified lignin particles derived from softwood kraft lignin. The lignin undergoes a two-step modification process: hydroxyethylation followed by esterification with oleic acid, resulting in a biopolymer dispersion. The dispersion is used to coat various surfaces, enhancing their hydrophobic properties. The process avoids toxic solvents, making it an environmentally friendly method for producing water-resistant coatings.

Pathway Description:

The process involves a two-step chemical modification of softwood kraft lignin. First, lignin undergoes hydroxyethylation using ethylene carbonate to add aliphatic hydroxyl groups. Then, oleic acid esterifies the hydroxyethyl lignin to form hydrophobic ester derivatives. These derivatives are dissolved in organic solvents, precipitated into water, and processed into stable aqueous dispersions, which are applied as hydrophobic coatings via spray and spin coating techniques.