A study of the relationship between the rheo-dielectric effect and the elasticity of viscoelastic materials

• Published in: Journal of rheology (New York : 1978) Vol. 55; no. 2; pp. 301 - 311
• Main Authors: Peng, Yiyan, Turng, Lih-Sheng, Li, Haimei, Cui, Zhixiang
• Format: Journal Article
• Language: English
• Published: Melville, NY The Society of Rheology 01.03.2011; Society of Rheology
• Subjects: Cross-disciplinary physics: materials science; rheology; Deformation; material flow; Dielectrostriction; Elasticity; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Linear viscoelasticity; Physics; Rheo-dielectric; Rheology; Solid mechanics; Static elasticity (thermoelasticity...); Strain-dielectric coefficient; Structural and continuum mechanics; Viscoelastic; Elasticity; Strain-dielectric coefficient; Rheo-dielectric; Viscoelastic; Dielectrostriction; Viscoelasticity; Dielectric materials
• ISSN: 0148-6055; 1520-8516
• DOI: 10.1122/1.3539654

Dielectrostriction is a rheo-dielectric phenomenon that relates the variation of dielectric properties of a material to deformation. For an initially isotropic material, two independent material parameters, called the strain-dielectric coefficients, α 1 and α 2 , are required to describe dielectrostriction in terms of strain. Deformation affects a material’s dielectric properties in two ways: (a) by introducing anisotropy in the material, which is characterized by α 1 , and (b) by changing the volume density of the polarizable species, which is associated with ( 1 3 α 1 + α 2 ) . Purely viscous fluids remain isotropic during any flow-induced deformation, and therefore the coefficient α 1 is always zero. In this paper, the dielectrostriction effect is studied in viscoelastic materials that are formulated to possess different degrees of elasticity. A special planar capacitance sensor rosette was employed to measure the coefficients α 1 and α 2 for these viscoelastic materials. The relationship between the material’s elasticity and the coefficient α 1 is discussed, together with some potential applications based on this relationship in the conclusion.