The Durability of Adhesive Joints: An Engineering Study
Abstract
Water diffusion through the adhesive is the rate controlling factor for the durability of many metal-to-polymer bonds exposed to moist environments. A methodology is proposed, to relate the diffusion coefficient of water in polymers to temperature, strain and penetrant concentration. The approach used is based on well known free volume theories. In the rubbery state, it is assumed that the transport kinetics is governed by the constant redistribution of the free volume, caused by the segmental motions of the polymeric chains. An expression for the diffusion coefficient is inferred from the temperature, strain and penetrant concentration of the free volume. It is shown that the free volume treatment can be extended to the glassy range by introducing a few additional features in the model. The stress dependence of solubility as well as the non-fickian driving forces contributing to mass transport are predicted from the Flory-Huggins theory.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1988
- Accession Number
- ADA197754
Entities
People
- D. A. Dillard
- Didier R. Lefebvre
- H. F. Brinson
Organizations
- Virginia Tech