Effects of Selected Wood Species and Moisture Content on PMDI Resin Application and Panel Properties

Authors

  • T. Michael Gruver
  • Nicole R. Brown
  • Jone S. Cionni
  • Timothy S. McCracken
  • William J. Nicola
  • Timothy Takah

Keywords:

pMDI, aspen, poplar, pine, composites, resin droplet size, internal bond strength, thickness swell

Abstract

This study investigated the effect of selected species and moisture conditions on resin distribution and composite panel properties. Flakeboard composites were made from aspen, pine, or poplar flakes that were equilibrated to 4, 8, or 12% moisture content (MC). Resin droplet size (resin "footprint") was measured, as was the percentage of the flake surface that was covered by resin. Aspen flakes showed higher resin coverage and also larger resin droplet sizes. Conversely, pine and poplar flakes had smaller resin droplets and lower resin coverage per flake surface, suggesting greater pMDI penetration. Internal bond (IB) testing revealed optimal performance for aspen flakes at 12% precure MC, and poplar and pine flakes at 8% precure MC. Modulus of rupture and modulus of elasticity results correlated with IB results. Aspen panels bonded at 8 and 12% MC had minimal thickness swell.

References

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Published

2008-04-25

Issue

Number 2 / April 2008

Section

Research Contributions

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