INDEX electric

If now the physical properties of the body (e.g., thermal expansion, compressibility, refractive index, electric and thermal conductivities, dielectric constant, and magnetic permeability) are measured along OPi, OP2, OP,. .. we find that all the bodies fall into one or other of two large groups —... 

Liquid crystal polymers (LCP) are polymers that exhibit liquid crystal characteristics either in solution (lyotropic liquid crystal) or in the melt (thermotropic liquid crystal) [Ballauf, 1989 Finkelmann, 1987 Morgan et al., 1987]. We need to define the liquid crystal state before proceeding. Crystalline solids have three-dimensional, long-range ordering of molecules. The molecules are said to be ordered or oriented with respect to their centers of mass and their molecular axes. The physical properties (e.g., refractive index, electrical conductivity, coefficient of thermal expansion) of a wide variety of crystalline substances vary in different directions. Such substances are referred to as anisotropic substances. Substances that have the same properties in all directions are referred to as isotropic substances. For example, liquids that possess no long-range molecular order in any dimension are described as isotropic. 

As its name suggests, a liquid crystal is a fluid (liquid) with some long-range order (crystal) and therefore has properties of both states mobility as a liquid, self-assembly, anisotropism (refractive index, electric permittivity, magnetic susceptibility, mechanical properties, depend on the direction in which they are measured) as a solid crystal. Therefore, the liquid crystalline phase is an intermediate phase between solid and liquid. In other words, macroscopically the liquid crystalline phase behaves as a liquid, but, microscopically, it resembles the solid phase. Sometimes it may be helpful to see it as an ordered liquid or a disordered solid. The liquid crystal behavior depends on the intermolecular forces, that is, if the latter are too strong or too weak the mesophase is lost. Driving forces for the formation of a mesophase are dipole-dipole, van der Waals interactions, 71—71 stacking and so on. 

Examples of such properties are conductivity, refractive index, electrical moment, dielectric constant, chelate formation, ion dissociation, phase transitions, solubility, and viscosity. Certain physical changes that occur when the photochromic entity is chemically attached to the macromolecular backbone of polymers are of special interest (see Chapter 1, Volume 2). 

The rate equation 5.5 and the first-order plot remain valid in terms of any physical variable f that is a linear function of the concentrations. This is usually true for properties such as refractive index, electric conductivity, specific gravity, and rotation of the plane of polarized light. In all such cases, x is defined as before by eqn 5.3, but with f instead of Ct. Equation 5.5 remains valid even if the variable changes its sign in the course of the reaction, as it might with rotation of the plane of polarized light. 

Hydrogen bonds were first detected through solubility studies (1497), and were quickly found by the many other classical methods available in the first quarter of the twentieth century. Vapor pressure and vapor density, molecular weight, dielectric constant, partition or distribution, molar volume, parachor, refractive index, electrical and thermal conductivity, and acoustic behavior are a few of the physical properties that reflect the presence of the H bond. 

Kier-Hall solvent polarity index - electric polarization descriptors... 

Molar volume and density, refr tive index, electrical and thermal conductivity, hygroscopicity... 

Geometric Mean Polarizability Effect Index electric polarization descriptors ( Polarizability Effect Index)... 

GMPEI = Geometric Molecular Polarizability Effect Index —> electric polarization descriptors (0 polarizability effect index)... 

Kier-Hall solvent polarity index —> electric polarization descriptors > Kier molecular flexibility index flexibility indices... 

Max. continuous temperature of use Coefficient of linear thermal expansion Thermal conductivity Oxygen Index Electrical volume resistivity... 

Max. continuous temperature of use Coefficient of linear thermal expansion Thermal conductivity Oxygen Index Electrical volume resistivity Processing Mold shrinkage Drying temperature Drying time Mold temperature Melt temperature Dimensional stability Trade names Elf Atochem Kynar 460 Solvay Solef 1000 series... 

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