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Wood Science and Technology

, Volume 43, Issue 1–2, pp 143–152 | Cite as

Modeling moisture absorption process of wood-based composites under over-saturated moisture conditions using two-part equations

  • Sheldon Q. ShiEmail author
  • Dongfeng Wu
Original

Abstract

The objective of this study was to investigate the moisture absorption process for wood-based composites subjected to over-saturated moisture conditions. Two stages are comprised in the moisture transfer process at the over-saturated moisture conditions, an initial stage which is the moisture transfer process mainly under fiber saturation point (FSP), and a second stage which is the moisture transfer process beyond the FSP. A model was developed based on two-part equations to describe the process, from which three coefficients (k 1 , k 21 , and k 22) can be used to quantitatively describe the moisture transfer process under the conditions. Two different wood-based composites, wood fiberboard and wood fiber/polymer composites (polymer content: 30%), were used to test the model at four different ambient temperatures (30, 45, 62, and 80°C). It was shown that the two-part equation can accurately describe the moisture absorption process under over-saturated moisture conditions. The moisture absorption rate in the initial stage was about 30–60% greater than that in the second stage for most of the cases evaluated in this study. The higher the temperature, the greater moisture absorption parameters were obtained. At both moisture absorption stages (below FSP and above FSP), the calculated activation energy for the moisture absorption rate of wood fiberboard was very close to that of wood fiber/polymer composites.

Keywords

Moisture Absorption Equilibrium Moisture Content Acrylonitrile Butadiene Styrene Adjustment Coefficient Fiber Saturation Point 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Forest Products DepartmentMississippi State UniversityMississippi StateUSA
  2. 2.Bioinformatics and Biostatistics DepartmentUniversity of LouisvilleLouisvilleUSA

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