Adhesives for wood

The most effective adhesives for wood joints have a moisture content between 8% and 12%. Apparently a monomolecular layer of water between the wood and the adhesive is necessary to provide the adhesive force, through hydrogen bonds. To correlate other factors with the new theory, an extensive microscopic study of glue joints in wood is being made. Research is directed to the various stresses and to the importance of such other factors as penetration of adhesives, surface texture and density, and surface damage before gluing.4. E. Marian, Forest Products Laboratory, Berkeley.