Characterization of Hydrolytic Degradation of U-f Joints Through Apparent Diffusivity

Authors

  • Jae Sik Na
  • Didier Ronze
  • André Zoulalian

Keywords:

Urea-formaldehyde, hydrolysis, aging, diffusivity, chemical degradation, mechanical degradation

Abstract

The hydrolytic aging of an adhesive joint (wood-urea/formaldehyde resin) is characterized by measurements of the apparent diffusivity of two inert gases within the bond. This kind of measurement is of some interest, because it includes both chemical and geometrical changes in joint structure.

Apparent diffusivities are determined in a diffusion cell after various degradation times in a cold water bath. Our results show that diffusivity increases with aging time with an asymptotic trend. Nevertheless, when the joint undergoes cyclic aging (immersion/drying), chemical degradation occurs mainly during the first cycle, while mechanical degradation observed during the drying steps also appears during the following cycles. The values of apparent diffusivity show that the solute transport is a real diffusional transport phenomenon and that resin joints are not porous.

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Published

2007-06-19

Issue

Number 4 / October 1996

Section

Research Contributions

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