Hydroxymethylfurfural: A key to increased reactivity and performance of fructose-based adhesives for particle boards

There is a push towards the use of renewable adhesives in particle board manufacturing industry. A remaining barrier for the successful implementation of carbohydrate-based adhesives is the necessity of a rapid cure behavior at lower temperatures (105–120 ◦C). The aim of this work was to study the effect of highly reactive, biobased 5-Hydroxymethylfurfural (HMF) on the cure speed in fructose-bishexamethylenetriamine (BHMT) adhesive. The technological suitability of these adhesives for the intended application in particle boards was done by combining adhesive characterization with thermal analysis and tensile shear strength development. Overall, HMF had a strong, positive effect on the reactivity and performance of these fructose-based adhesives, especially at lower hot-press temperatures. The tensile shear strength development of fructose/HMF/BHMT adhesives was comparable to commercial, fossil-based urea-formaldehyde resin at 120 ◦C. A sufficient tensile shear strength of 5.0 ± 0.3 N/mm2 was reached after press times as low as 30 s and 6.2 ± 0.1 N/mm2 after pressing for 150 s at 105 ◦C. This suggests fructose-HMF-BHMT adhesives have sufficient reactivity and performance and as such are a promising adhesive for a cleaner production of particle boards. Their rapid cure behavior is among the best of previously reported HMF-based adhesives.