Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 12, 1999
Publication Date: N/A
Technical Abstract: Foam extrusion is a mode of plywood glue application that has several advantages over other popular methods of applying adhesives. Foamed plywood glues currently use animal blood as their only extender, but concerns about animal blood's limited supply and health issues have prompted the search for alternate protein extenders. Our research goal is to determine if soy protein sources can replace animal blood protein in foamed glues. Based on their excellent foaming capacities and stabilities from earlier tests, three soy flours (Centex 4030, Nutrisoy 7B, Soyafluff) and five soy protein concentrates (Arcon F, Procon 2000, Promax 70, Promine HV, Response 4400) were selected to replace spray-dried animal blood in foamed glue formulations. The adhesive performances of the animal blood or soy-based foamed glues were evaluated on the basis of bond strength and wood failure ratings of plywoods that were processed under laboratory and pilot-plant conditions. Laboratory results showed that glues containing Procon or Promax soy protein concentrate produced greater bond strength and wood failure ratings than did the control glue with animal blood protein. Glues that contained the other soy flours or concentrates were as good as the control glue. Under pilot scale conditions, glues containing Nutrisoy flour, Arcon F or Procon 2000 demonstrated mixing and foaming properties that were nearly similar to that of the control glue. Formulations containing Promax did not produce foamed strands, but a 1:1 mixture with animal blood exhibited mixing and foaming properties that were identical to that of the control glue. Bond strength and wood failure evaluations on the pilot plant plywood specimens are ongoing.