Micro-Fibrillated Cellulose (MFC) is a new type of bio-based additive, coming from wood cellulose. It can compete and substitute oil derived chemicals in several application fields. In the present work, the use of micro-fibrillated cellulose, in waterborne adhesive systems applied in the manufacture of composite wood-based panels was evaluated. Research was conducted to test the potential of improving the performance of wood-based panel types such as particleboard, waferboard or randomly-oriented strand board and plywood, by the application of MFC and the substitution of conventional and non-renewable chemical compounds. The approaches followed to introduce MFC into the adhesive systems were three, i.e., MFC 2% suspension added during the adhesive resin synthesis, MFC 10% paste admixed with the already prepared adhesive resin and MFC 2% suspension admixed with the already prepared resin. It was found that MFC improves not only the performance of the final wood panel products but also the behaviour of the applied adhesive polymer colloids (e.g., rheology improvement), especially when admixed with the already prepared resins. Moreover, it was proven that when MFC is introduced into the adhesive resin system, there is a possibility of decreasing the resin consumption, by maintaining the board performance. MFC’s robustness to pH, shear and temperature makes it a highly interesting new additive for adhesive producers. In addition, its natural origin can give adhesive producers the opportunity to move over to more environmentally friendly product solutions.

In this work, we present the fabrication of low-cost, stable nanocellulose colloidal suspensions with an average particle size of approximately 160 nm, produced via a straightforward, solvent-free ultrasonication process that eliminates the need for corrosive chemicals or energy-intensive mechanical treatments. The resulting nanocellulose suspensions were utilized as reinforcing additives in urea-formaldehyde (UF) resins, which were subsequently applied in the production of particle boards. This approach addresses the increasing EU regulatory constraints regarding low formaldehyde-to-urea (F/U) molar ratios and the broader need for biobased, eco-friendly alternatives in the wood adhesive industry. Mechanical testing of the nanocellulose reinforced boards revealed notable improvements in the internal bond strength and modulus of rupture, along with a significant decrease in formaldehyde release compared to boards produced with conventional UF resins. These findings highlight the potential of ultrasonication-derived nanocellulose as an environmentally friendly, cost-effective additive to enhance the mechanical performance and reduce the environmental impact of UF-based wood composites.

Bio-based phenolic resins were developed with phenol substitution levels of 20% and 40% with crude extracts obtained from spent coffee grounds. The experimental resins were characterized in terms of their physical, chemical and bonding properties and exhibited the typical property levels of Phenol-Formaldehyde-type resins. Plywood panels were produced bonded with the novel experimental resins, exhibiting satisfactory performance, comparable to the reference panels in terms of both shear strength and wood failure, based on the requirements of the European standards. The results demonstrate the potential of using biomass-derived compounds as substitutes for petrochemical phenol in the production of wood adhesives, thereby increasing the bio-based content of the wood panel composites produced with them and improving their sustainability.