Nano-reinforced adhesives: Effects of graphene, silica, and cellulose on mechanical properties of laminated wood materials

This study investigated the effects of graphene, silica, and cellulose nanoparticles on the mechanical properties of laminated wood specimens using polyvinyl acetate (PVAc), urea-formaldehyde (UF), and epoxy (EPX) adhesives. Poplar (Populus nigra) and beech (Fagus sylvatica) veneers (4 mm thick) were bonded using adhesives enhanced with varying concentrations of nanoparticles: graphene (0.25 % and 0.50 %), silica (1 % and 2 %), and cellulose (1 % and 2 %). The laminated wood specimens were tested for modulus of elasticity (MOE), modulus of rupture (MOR), compressive strength (CS) and bonding strength (BS). The results showed that the EPX yielded the highest mechanical strength, followed by UF, while PVAc exhibited the lowest. The addition of all nanoparticles improved performance compared to the base adhesives. Graphene additions significantly improved MOE, MOR, and CS, while cellulose and silica primarily enhanced BS strength. Generally, increasing nanoparticle concentration enhanced mechanical properties, with the exception of BS, which decreased with higher silica concentration. These results demonstrate the potential for tailoring laminated wood properties by selecting specific nanoparticle types and concentrations, offering opportunities for optimized and potentially more sustainable material utilization across diverse applications, from furniture to structural components.