Interfacial Water Transport and Embrittlement in Polymer-Matrix Composites

MRS Proceedings ◽

10.1557/proc-304-27 ◽

1993 ◽

Vol 304 ◽

Cited By ~ 1

Author(s):

A. Lekatou ◽

Y. Qian ◽

S. E. Faidi ◽

S. B. Lyon ◽

N. Islam ◽

...

Keyword(s):

Water Transport ◽

Polymer Matrix ◽

Volume Fraction ◽

Water Saturation ◽

Polymer Matrix Composites ◽

Pure Water ◽

Fickian Diffusion ◽

Interfacial Water ◽

Matrix Composites ◽

Electrical Measurements

AbstractDisordered glass microsphere-epoxy composites have been used in a study of diffusional, electrical and mechanical effects of interfaces in polymer-matrix composites exposed to pure water. Mass gain measurements on composites manufactured from 10 μm silane-treated microspheres indicate initial near-Fickian diffusion with water saturation times on the order of 500 h. However, electrical measurements indicate water transport at rates at least 100 times more rapid. This behaviour is interpreted in terms of a cellular microstructure with areas of low cross-link density separating highly cross-linked areas. Rapid water transport can thus occur in areas of low cross-linking, even without the contribution of connected clusters of particles where rapid interfacial water transport occurs substantially ahead of the main diffusion front. Reductions in ultimate tensile strength and fracture energy in dry and water-saturated tensile test specimens are observed with increasing volume fraction of glass spheres but with a distinct plateau between about 6% and 12% Vf. This can be explained in terms of secondary cracking below the percolation threshold which causes toughening of the composite. However, a few % above pc (≍ 16%), most particles belong to the percolating cluster and the primary crack can grow without hindrance.

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Numerical Investigation of Thermal Conductivity of Particle Dispersive Composites Based on Fractal Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.616-618.1808 ◽

2012 ◽

Vol 616-618 ◽

pp. 1808-1812

Author(s):

Xiao Chuan Li ◽

Xiang Yong Huang

Keyword(s):

Thermal Conductivity ◽

Heat Conduction ◽

Polymer Matrix ◽

Volume Fraction ◽

Polymer Matrix Composites ◽

Fractal Theory ◽

High Heat ◽

Matrix Composites ◽

Filling Fraction ◽

High Heat Transfer

Heat conduction performance of particle dispersive composites has been numerically investigated by using Finite volume method (FVM) and fractal theory. The effects of the thermal conductivity of particle and polymer matrix, the volume fraction of conductive particle, the dispersion and reunion form of particles on the effective thermal conductivity of composites are analyzed in detail. Results from the research indicate that thermal conductivities of composites will increase nonlinearly along with the increase of filling fraction of particles. Keeping the filling fraction constant, the dispersion and reunion form and direction of particles has significant effect on heat conduction performance of composite. Simple use of high thermal conductivity particles has limited effect on thermal performance of composites. Enhancing the contacts of particle in the direction of heat exchange and forming high heat transfer channels are the main and economical ways to improve heat conduction performance of particulate filled polymer matrix composites.

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Polymer Matrix Composites Subjected to Low Velocity Impact: Effect of Fibre Volume Fraction

Science and Engineering of Composite Materials ◽

10.1515/secm.2000.9.4.207 ◽

2000 ◽

Vol 9 (4) ◽

Author(s):

N.K. Naik ◽

Sailendra Meduri

Keyword(s):

Polymer Matrix ◽

Volume Fraction ◽

Polymer Matrix Composites ◽

Fibre Volume Fraction ◽

Fibre Volume ◽

Low Velocity Impact ◽

Matrix Composites ◽

Low Velocity ◽

Velocity Impact ◽

Impact Effect

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On the Mechanical and Physical Properties of Recycled Polymer Matrix Composites Reinforced with Cooper Powder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.23.127 ◽

2007 ◽

Vol 23 ◽

pp. 127-130

Author(s):

Victoria Chifor ◽

Radu L. Orban ◽

Nicolae Jumate

Keyword(s):

Electrical Resistivity ◽

Physical Properties ◽

Polymer Matrix ◽

Volume Fraction ◽

Polymer Matrix Composites ◽

Matrix Composites ◽

Polyethylene Matrix ◽

Critical Volume Fraction ◽

Mechanical And Physical Properties ◽

Powder Content

The influence of cooper powder as reinforcing phase on the main mechanical and physical properties of recycled polyethylene matrix composites has been investigated. The obtained elastic modulus increases up to the upper adopted reinforcing level (∼10 [vol. %]), while elongation and fracture energy decrease. The UTS values remain quite constant within the reinforcing content interval. Electrical resistivity proved to depend, to a great extent, on the reinforcing particle distribution inside the polymer matrix. It has a sudden drop when a continuous electrical conductive path is formed at a critical volume fraction of metal particles. At a lower content, instead, it slowly decreases as reinforcing powder content increases. Both the mechanical properties and values for electrical resistivity are similar to those published for polymers obtained directly from monomers.

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Modeling the Transport of Low-Molecular-Weight Penetrants Within Polymer Matrix Composites

Applied Mechanics Reviews ◽

10.1115/1.2202873 ◽

2006 ◽

Vol 59 (5) ◽

pp. 249-268 ◽

Cited By ~ 43

Author(s):

David A. Bond ◽

Paul A. Smith

Keyword(s):

Heat Conduction ◽

Environmental History ◽

Polymer Matrix ◽

Polymer Matrix Composites ◽

Analytical Models ◽

Fickian Diffusion ◽

Matrix Composites ◽

Scientists And Engineers ◽

Structural Engineers ◽

Kinetics Of

In 1855 Fick reported on the diffusion of liquid through a membrane and proposed that there was an analogy between this process and that of heat conduction allowing him to transcribe the mathematical equation for heat conduction derived in 1822 by Fourier into a form to represent this diffusion of liquid. This model, known as Fickian diffusion, has become the baseline against which the characteristics of liquid diffusion are measured to the point where anomalous diffusion is known generically as non-Fickian. Numerous authors have attempted to develop models to cover all aspects of non-Fickian diffusion resulting in a very large number of models that consider the effect of parameters as varied as the chemical makeup, geometric dimensions, environmental history, stress state, and damage status of the material, as well as the likelihood of multiple diffusion mechanisms being responsible for transport of the water molecules. Of particular interest to structural engineers is the transport of moisture in polymer matrix composites owing to the plasticizing effect the moisture may have on the composite and the potential for the moisture to induce localized damage. This paper reviews analytical models that are relevant to the transport of moisture in structural composites. In doing so the benefits and limitations of the various models and techniques are presented in order to provide a reference for scientists and engineers attempting to describe the kinetics of moisture in composites accurately. There are 160 references cited in this review article.

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Micromechanics-based approach for the effective estimation of the elastic properties of fiber-reinforced polymer matrix composite

Journal of Micromechanics and Molecular Physics ◽

10.1142/s242491301950005x ◽

2019 ◽

Vol 04 (03) ◽

pp. 1950005

Author(s):

V. S. Kathavate ◽

D. N. Pawar ◽

A. S. Adkine

Keyword(s):

Elastic Properties ◽

Polymer Matrix ◽

Volume Fraction ◽

Polymer Matrix Composites ◽

Effective Elastic Modulus ◽

Test Material ◽

Matrix Composites ◽

Fiber Volume ◽

Reinforced Polymer ◽

Eshelby’S Tensor

In this paper, we proposed a revised Mori–Tanaka model for the effective estimation of the elastic properties at lower fiber volume fraction. A review of some notable micromechanics-based models with the theories proposed by Voigt and Reuss, Hashin–Shtrikman model, Mori–Tanaka method and dilute dispersion scheme is carried out, and a critique is presented focusing on the limitations of these models. Finite Element (FE) simulations are performed using Representative Volume Element (RVE) technique to rationalize the analytical results. Our results revealed that revised Mori–Tanaka estimates and FE predictions are in agreement. Elastic properties of the test material are dependent on size of RVE suggesting the effective elastic modulus evaluated using RVE forms the lower bounds of true effective values. However, we still believe that there is room for the debate for evaluating the elastic properties of these composites at larger volume fractions with the inclusion of Eshelby’s tensor in Mori–Tanaka scheme. Thus the efficacy of micromechanics-based models for the effective estimation of elastic properties of polymer matrix composites is highlighted. Our findings may provide new significant insights of the effective estimation of elastic properties of PMC using micromechanics-based approach.

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