The Internal Bond and Shear Strength of Hardwood Veneered Particleboard Composites


  • Poo Chow
  • John J. Janowiak
  • Eddie W. Price


Accelerated aging, adhesive, exterior particleboard, glueline, hard maple, hardwood composite, internal bond, red oak, shear strength, waferboard


The effects of several accelerated aging tests and weather exposures on hardwood reconstituted structural composite panels were evaluated. The results indicated that the internal bond and shear by tension loading strength reductions of the panels were affected by the exposure test method. The ranking of the effects of various exposure tests on strength values in an increasing order of severity was (1) 24-hour soak, (2) 1-hour boil, (3) 2-hour boil, (4) ASTM-6 cycles, and (5) WCAA-6 cycles. Both ASTM and WCAA tests had similar influences on IB and shear strength properties. Also, 4 cycles of either of these tests resulted in about the same degree of strength reduction as 6 cycles. In addition to test methods, a few construction variables were evaluated. The type of glueline, dry phenolic resin film and wet melamine-urea formaldehyde resin used to laminate the veneer over the core material yielded similar strength values. Other construction variables evaluated indicated that panels with an exterior particleboard core made from smaller particles as compared to wafers had higher IB values than waferboard core panels.


American Society for Testing and Materials. 1981. Standard methods of evaluating the properties of wood-base fiber and particle panel materials. ASTM Designation D 1037-72, Part 22. ASTM, Philadelphia, PA.nAmerican Society for Testing and Materials. 1982. Standard methods of evaluating strength properties of adhesives in plywood type construction in shear by tension loading. ASTM Designation D 906-64 (Reapproved 1976), Part 22, ASTM, Philadelphia, PA.nBiblis, E., and W. C. Lee. 1984. Properties of sheathing-grade plywood made from sweetgum and southern pine. Wood Fiber Sci. 16(1):86-92.nChow, P. 1972. Modulus of elasticity and shear deflection of walnut-veneered particleboard composite beam in flexure. For. Prod. J. 22(11):33-38.nChow, P., and J. J. Janowiak. 1983. Effects of accelerated aging tests on some bending properties of hardwood composite panels. For. Prod. J. 33(2):14-20.nChow, P., and M. R. Redmond. 1981. Humidity and temperature effects on MOR and MOE of hard maple-veneered medium density fiberboard. For. Prod. J. 31(6):54-58.nJokerst, R. W., J. F. Lutz, and W. C. Kruel. 1976. Red oak-cottonwood plywood after one year exterior exposure. Plywood and Panel. 17(2):14-17.nLutz, J. F., and R. W. Jokerst. 1974. If we need it-Construction plywood from hardwood is feasible. Plywood and Panel. 14(9):18-20.nMahoney, L. 1975. Economic considerations for the manufacture of structural composite panels. For. Prod. J. 25(9):61-63.nNational Bureau of Standards. 1974. U.S. Products Standard P 51-74 for construction and industrial plywood. Washington, DC.nNational Particleboard Association. 1980. Revised standard for mat-forming particleboard. Plywood and Panel 20(11):30-32.nSAS Institute. 1981. SAS users' guide. SAS Institute, Gary, NC.nShen, K. C., and B. Wrangham. 1971. A rapid accelerated-aging test procedure for phenolic particleboards. For. Prod. J. 21(5):30-32.nSteel, R. G. D., and J. H. Torrie. 1980. Principles and procedures of statistics-A biometrical approach. McGraw-Hill, Inc., New York, NY.nU.S. Forest Service. 1973. The outlook for timber-The United States forest resources report. U.S.D.A. No. 20. U.S. Government Printing Office, Washington, DC.nWest Coast Adhesive Manufacturers Association. 1966. A proposed new test for accelerated aging of phenolic resin bonded particleboard. For. Prod. J. 16(6):19-23.n






Research Contributions