A variation of dielectric response with deformation, called dielectrostriction, provides a new approach for in-line monitoring properties and structure of materials. The dielectrostriction effect resembles a well-known birefringence phenomenon which has been widely used for NDE of transparent materials. While birefringence is described by the stress-optic rule, the stress-dielectric rule applies to dielectrostriction. However, dielectrostriction measurements can be applied to both transparent and opaque dielectric materials, require a much simpler measurement technique, are capable of measuring local stresses/strains and can be implemented for material processing and health monitoring of structures. Planar capacitor sensor setup is implemented to detect the dielectrostriction effect in both liquid and solid polymers. Dielectrostriction effect and the stress-dielectric relationship are studied for solid polycarbonate subjected to uniaxial tensile load. Similar results are obtained for liquid polymers in oscillatory shear flow.
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