Effects of Supercritical Fluid Treatments on Physical Properties of Wood-Based Composites


  • Menandro N. Acda
  • Jeffrey J. Morrell
  • Keith L. Levien


Composites, preservative treatment, supercritical fluid, plywood, medium-density fiber-board, particleboard, flakeboard, strength properties


The effects of supercritical fluid (SCF) impregnation on physical properties of composites were investigated at various pressures, temperatures, and treatment times with carbon dioxide as the fluid and tebuconazole as a biocide. In general, within the ranges tested, SCF treatment had no negative effects on modulus of rupture, (MOR), modulus of elasticity, (MOE), or dimensional stability of particleboard, flakeboard, or medium-density fiberboard; in some instances, SCF treatment appeared to be associated with slight property improvements in some panel types. Shear tests of plywood suggested a similar lack of treatment effect. Results indicate that, despite the elevated pressure employed during the process, SCF impregnation does not adversely affect the mechanical properties of various wood-based composites.


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