The bio-adhesives market is growing rapidly, and there is a strong need for new bio-based adhesives. In this master’s thesis, we investigated the adhesive properties of bacterial biofilms on spruce wood. We tested bacterial biofilms of different species and further focused on those of E. coli 1655 and B. subtilis 3610. We determined the rheological properties and surface energies of these two biofilms. After one day of drying, both biofilms showed comparable adhesive properties; however, after four days, the E. coli biofilm performed better. Rheological tests showed that the B. subtilis biofilm is more viscous and more resistant to mechanical forces, whereas the E. coli biofilm has more favorable balance between viscous and elastic modulus for adhesion and spreads better over the surface upon application. Measurements of surface energies indicated that the E. coli biofilm is more suitable, as its greater compatibility with wood enables better penetration into the wood and thus a larger contact area with the adhesive. The results suggest that bacterial biofilms have potential as wood-adhesive materials.
|
