BioGlue-Center webinar with Mojhan Nejad

Abstract

Lignin is a natural glue in the wood, thus a promising biopolymer for formulating biobased adhesives for wood products. This webinar explores the production of biobased adhesives, in which technical lignins are used to fully replace petrochemical phenol and polyol in the formulation of phenolic and polyurethane (PU) adhesives.

The performances of these lignin-based adhesives were evaluated against conventional fossil-derived counterparts for manufacturing plywood and mass timber. In phenolic resin, in addition to using lignin, we also entirely replaced formaldehyde with a biobased, less toxic dialdehyde (glyoxal). While the resulting lignin-glyoxal adhesive exhibited good dry adhesion, it failed boil-water tests, making it suitable for interior-grade plywood and OSB applications.

On the other hand, the two-component lignin-based polyurethane (PU) adhesives demonstrated outstanding dry and wet adhesion strengths when cured at room temperature, outperforming conventional petrochemical PU adhesives currently used in mass timber production (CLT and glulam). This webinar will also cover the suitability of various lignins for adhesive applications and provide insights into the fundamental reactions of lignin with formaldehyde and isocyanate.

Biography

Mojgan Nejad is an Associate Professor with a joint appointment in the Department of Forestry and the Department of Chemical Engineering and Materials Science at Michigan State University. She holds a bachelor’s degree in applied chemistry and a PhD in Wood Science. Her current research focuses on developing lignin-based coatings, adhesives, foams, and composites, primarily in collaboration with industry partners. Dr. Nejad's work on lignin valorization aims to fully replace phenol, polyol, and bisphenol-A in phenolic, polyurethane, and epoxy resins using technical lignins. She has received several awards, including the Adhesive and Sealant Council Innovation Award in 2018, the Polyurethane Foam Association (PFA) Herman Stone Technical Excellence Award in 2023, and the CARES Automotive Sustainability Innovation Award in 2024.