Variation in surface roughness, wettability and some plywood properties after preservative treatment with boron compounds

Abstract

Wood can be protected from attack by pests with preservative treatment of the many different preservatives available for wood; borates are generally preferred for indoor uses and can be used to treat solid wood and engineered wood composites. Although treated panels make up a large part of the plywood market, treatment with some wood preservatives has been known to interfere with the bond integrity of glued wood specimens. In this study, the possible effects of borax and boric acid treatment on adhesive wettability and surface roughness of veneers and bond strength and hygroscopicity of plywood panels were tested. No clear changes in surface roughness after borax and boric acid treatment were observed. Poor wettability on the surfaces of alder and beech veneers with UF resin after borate treatments was obtained. Bond strength values of plywood panels decreased and equilibrium moisture content (EMC) of plywood panels increased after borate treatment.