Synthesis and characterization of lignin-based adhesive cross-linked with furfuryl alcohol–formaldehyde and epoxy resins

Abstract

Lignin extracted from corn stalk was cross-linked with furfuryl alcohol-formaldehyde (FF) resin in the laboratory to prepare a bio-based adhesive, with good water resistance, for producing particleboard. The results of matrix-assisted laser desorption-ionization time-of-flight mass spectroscopy and 13C nuclear magnetic resonance spectroscopy indicated that furfuryl alcohol reacted with formaldehyde under acidic conditions. The –CH–(OH)– groups were involved in the cross-linking of the lignin–furfuryl–formaldehyde (LFF) adhesive. The internal bond strength of the LFF-bonded particleboard showed that the cured LFF was improved and had higher performance compared to the lignin–furfuryl alcohol (LF) adhesive. The LFF with 9% epoxy resin adhesive had an excellent modulus of elasticity, which was higher than those of PF and LF adhesives.