Aging of Organic Matrix Composite Materials
Published Online: 15 SEP 2011
Copyright © 2011 John Wiley & Sons, Inc. All rights reserved.
Wiley Encyclopedia of Composites
How to Cite
Colin, X. and Verdu, J. 2011. Aging of Organic Matrix Composite Materials. Wiley Encyclopedia of Composites. 1–16.
- Published Online: 15 SEP 2011
This article deals with aging mechanisms and kinetics in organic matrix composites, focusing on water-polymer (humid aging) and oxygen-polymer (thermo-oxidative aging) interactions.
The first section is devoted to problems common to all kinds of chemical aging, with emphasis on specific aspects of composite materials, for instance, role of interphase/interface in aging processes or anisotropy of water or oxygen diffusion in fiber-reinforced materials. The effects of mechanical loading on diffusion kinetics and the diffusion-reaction coupling are briefly evoked.
The second section deals with humid aging. It is important to distinguish physical processes linked to plasticization and swelling of the polymer matrix by water and chemical (hydrolytic) aging, an ionic step-by-step reaction, which affects only polycondensates, especially polyesters. Hydrolysis induces random chain scission responsible for embrittlement and sometimes osmotic cracking responsible for blistering of the glass fiber-polyester composites.
The third section concerns thermo-oxidative aging that results from a branched radical chain reaction. This kind of aging occurs when the material is exposed to high temperatures during its processing or in its use conditions, which is the case of many aerospace applications. The basics of nonempirical kinetic modeling are presented. The last section deals with the consequences of thermo-oxidation on the thermomechanical properties including glass transition temperature, elastic properties, and fracture properties.
- organic matrix composites;
- water absorption;