Bonding high-moisture veneers

Clark, R. J. Investigation of a New Resin as an Exterior Adhesive to Bond High Moisture Content Veneers, MS Thesis, Oregon State University, Corvallis, June 1986. 

Clarke, M., Steiner, P.R. and Anderson, A.W., United States patent USP 4,824,896. Phenol formaldehyde adhesives for bonding wood pieces of high moisture content and composite board and veneers bonded with such adhesive. Assigned to the inventors, 1989. 

Chen (46) used sodium hydroxide extracts from southern pine Pinus spp.) bark, peanut Arachis hypogea) hulls, and pecan Carya illinoensis) pith as 20% replacements for phenol-formaldehyde resins in plywood adhesives. Bond quality was highly dependent on veneer moisture content and assembly time. Exterior quality bonds (U.S. Product Standard PS-1-74) in southern pine plywood were obtained if the veneer moisture content was 7.0% with 60-minute assembly times. Phenol-formaldehyde resin replacements could be increased to 40% by peanut hull and pecan pith extracts when the extraction solutions containing 5% of sodium hydroxide were used (45). Southern pine veneer (0.32 cm) was spread at a rate of 41.5 to 42.5 g/lOOOcm of double glue line and the layups were stored in a... 

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