Mechanism of Moisture Absorption in Metal-Filled Epoxies
Moisture absorption is one of the main parameters affecting the thermomechanical behavior of viscoelastic composites. Absorbed moisture has as a result the lowering of the glass-transition temperature, while, on the other hand, contributes to a change of the residual stresses due to matrix swelling. These effects of absorbed moisture, are closely related to the microstructure of the composite under investigation. More precisely, as it is well known, during the manufacture of a composite material around each one of the inclusions a third phase is developed due to physicochemical interaction between filler and matrix. It has been shown that this extra phase affects the overall behavior of the composite since it regulates the degree of adhesion between filler and matrix. In the case of moisture absorption the extent of this extra phase, which is called “boundary interphase”, changes, while, at the same time, there is a change in the mechanical behavior of the composite. Thus, there is an interrelation between moisture absorption, mechanical behavior of the composite and extent of the boundary interphase. In the present paper, a quantitative interrelation of the abovementioned three parameters is derived, while, based on these results, the mechanism of moisture absorption in metal-filled composites is explained.
KeywordsResidual Stress Immersion Time Boundary Interphase Moisture Absorption Interphase Layer
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- 1.Yu, S. Lipatov, “Physical Chemistry of Filled Polymers”, (Russ). Kiev, (1967).Google Scholar
- 2.Yu. S Lipatov, L. Sergeeva, “Adsorption of Polymers”, New York: J. Wiley (1974).Google Scholar
- 3.Yu. S. Lipatov, Jnl. Polymer Sci. C., Vol. 42, p. 855 (1973).Google Scholar
- 4.Yu. S. Lipatov, Advances in Polymer Science, Vol. 22, pp. 1–59, (1975).Google Scholar
- 11.P.S. Theocaris, G.C. Papanicolaou and E.P. Sideridis, Jnl. Reinforced Plastics and Composites, Vol. 1, p. 90 (1982).Google Scholar
- 17.C.E. Browning, G.E. Husman and J.M. Whitney, ASTM STP 617, p. 481 (1977).Google Scholar
- 18.H. Lee and K. Neville “Handbook of Epoxy Resins”, McGraw-Hill, New York, 1967, p. 22–53.Google Scholar
- 19.AFML/AFOSR, Mechanics of Composites Review, Dayton, (1976).Google Scholar