Electric fields structure-property relationships

The present work summarizes opportunities of using high-resolution synchrotron and standard xrd techniques for structural characterization as well as for investigations of structure-property-relationships. xrd will be used to determine quantitatively the phase content of morphotropic pzt. Temperature dependent measurements provide information about the phase transformation of morphotropic donor doped pzt ceramics and high-resolution synchrotron X-ray diffraction gives information about the extrinsic and intrinsic contributions to the electric field induced strain, xrd results are finally compared with electrical measurements to analyze the interactions among microstructure, phase content and properties. 

In recent years, both academic and industrial research on new nanocomposites based on clays fillers within a polymer matrix have rapidly developed [1-3]. Advances in this field have shown that these materials may exhibit enhanced properties (for example, increased heat and mechanical resistance, electrical conductivity and gas barrier properties) compared to the corresponding unfilled polymer matrix. Despite recent progress in the design of these nanoimmposites, many structure-properties relationships are still to be elucidated. 

Synthetic composite materials have passed through intensive progress in the last fifty years. Originally, synthetic polymers were blended with inorganic fillei-s for the sake of price reduction on the other hand, fillers cause considerable change in many physical properties of polymei-s. Later, functional fillers bringing other effects to polymer composites, such as magnetic or electrical properties, bioactivity, reduced flammability, etc., were introduced in the 80 s and 90 s. Nanocomposites can offer both miique properties and multi-functionality, which are well applicable in various fields. Undoubtedly, if one wants to use polymer nanocomposites in specific applications, the structure-property relationships have to be fully understood in these miique materials first. 

Interpretation of the SAG° values in terms of the binding site chemotopography is, in principle, admissible since the extrathermodynamic relationships implicitly contain the relation between the macroscopic quantity (AG° ) and the microscopic properties (atomic structure, geometry, charge distribution, electric field) [102]. However, any such interpretation has to consider that the observed AG value is a composite quantity ... 

If the medium is isotropic, is a scalar, i.e. the relationship between E and Plinear IS independent of the direction of the field vector E and the polarization is parallel to E. Many polymers possess amorphous structures and their optical properties are isotropic. However, electro-optic polymeric systems containing polar moieties can be made anisotropic by orienting these moieties, for example, by electric field-induced or optical alignment. In this case, the polarization is not necessarily parallel to the direction of E and its component in one direction is related to the field components in all three directions ... 

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