Journal ArticleDOI
Stress dependence of water diffusion in epoxy resin
A. A. Fahmy,J. C. Hurt +1 more
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TLDR
In this article, the effect of stress on the diffusion of water in glassy polymers is analytically treated, and the free volume concept is established and in turn is related to the diffusion coefficient yielding the following formula: Dσ = Doe(6 to 10)σ/G where Dσ and Do are the diffusion coefficients in the presence and absence of stress respectively, G is the shear modulus, and σ is the stress.Abstract:
The effect of stress on the diffusion of water in glassy polymers is analytically treated. Utilizing the free volume concept the effect of stress on the free volume fraction is established and in turn is related to the diffusion coefficient yielding the following formula: Dσ = Doe(6 to 10)σ/G where Dσ and Do are the diffusion coefficients in the presence and absence of stress respectively, G is the shear modulus, and σ is the stress. Experiments are described which demonstrate that in a bent epoxy bar, more water is picked up at the tension side than at the compression side. Theory and experiment are discussed and compared.read more
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Self-etch vs etch-and-rinse adhesives: effect of thermo-mechanical fatigue loading on marginal quality of bonded resin composite restorations.
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The mixing mechanism during lithiation of Si negative electrode in Li-ion batteries: an ab initio molecular dynamics study
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Durability study of pultruded CFRP plates immersed in water and seawater under sustained bending: Water uptake and effects on the mechanical properties
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References
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Book
Theory of elasticity
TL;DR: The theory of the slipline field is used in this article to solve the problem of stable and non-stressed problems in plane strains in a plane-strain scenario.
Book
Physical aging in amorphous polymers and other materials
TL;DR: The aging of polymeric materials and the alteration of corresponding physical properties are described in this paper, where the aging process is described in terms of the physical properties of the polymeric material.
Journal ArticleDOI
The mechanisms of elevated temperature property losses in high performance structural epoxy resin matrix materials after exposures to high humidity environments
TL;DR: In this paper, the effect of absorbed moisture on the epoxy resins' glass transition temperature, T(g), was determined as a function of both simple humidity and real-life exposures.
Journal ArticleDOI
Interfacial Mechanisms of Moisture Degradation in Graphite-Epoxy Composites
TL;DR: In this paper, a detailed study of the kinetics of environmental degradation in graphite-epoxy composites shows a close correlation between analytical predictions and experimentally observed changes in interlaminar shear and fracture energy response under high moisture exposure conditions.
Journal ArticleDOI
Surface Energy Analysis of Treated Graphite Fibers
TL;DR: Wettability measurements and surface energy analysis are applied to isolate the London-d and Keesom-p polar contributions to solid-vapor surface tension of surface treated graphite fibers.