Properties, electrical optical

A. phase transitions, volumetric properties, calorimetric properties, electrical/optical/magnetical properties, mechanical and acoustic properties. 

R. Saito, M. Fujita, G, Dresselhaus, and M. S. Dresselhaus, In Electrical, Optical and Magnetic Properties of Organic Solid State Materials, MRS Symposia Proceedings, Boston. Edited by L. Y. Chiang, A. F. Garito, and D. J. Sandman, vol, 247, p. 333, Pittsburgh, PA, Materials Research Society Press (1992),... 

Each plastic in this database is first characterized by descriptive data such as its trade name, manufacturer, product group, form of supply, or additives. Then follows complex technical information on each material, with details of fields of application, recommended processing techniques, and special features. The central element of this material database is the numerical values it gives on a wide range of mechanical, thermal, electrical, optical, and other properties. All these items can... 

POLYMAT materials data for plastics POLYMAT Materials Data for Plastics contains property values, e.g. mechanical, thermal, electrical, optical, rheological properties and text fields, e.g. special... 

The study of materials has traditionally centered on the influence of molecular composition and microstracture on mechanical, electrical, optical, and chemical properties. At the molecular level are a variety of research frontiers that can profitably draw chemical engineers into close collaboration with physical and theoretical chemists. They include the following research areas. 

On a smaller scale many new functional polymers are produced having valuable properties for electrical, optical or magnetic applications. There exist numerous metal catalysed processes and we will discuss only a few to explain basic concepts using both examples from bulk polymers and fine chemical, high-value polymers. 

Secondly, the electron theory seeks to elucidate the relation between the catalytic and electronic properties of a semiconductor. At the present time we possess a vast amount of experimental material which allows us to infer that the electronic processes taking place in a semiconductor and determining its electrical, optical, and magnetic properties also determine its chemisorptive and catalytic properties. It is the aim of the theory to establish the connection between these two groups of properties. 

Metal ion modified polyimide films have been prepared to obtain materials having mechanical, electrical, optical, adhesive, and surface chemical properties different from nonmodified polyimide films. For example, the tensile modulus of metal ion modified polyimide films was increased (both at room temperature and 200 0 whereas elongation was reduced compared with the nonmodif ied polyimide (i). Although certain polyimides are )cnown to be excellent adhesives 2) lap shear strength (between titanium adherends) at elevated temperature (275 0 was increased by incorporation of tris(acetylacetonato)aluminum(III) (2). Highly conductive, reflective polyimide films containing a palladium metal surface were prepared and characterized ( ). The thermal stability of these films was reduced about 200 C, but they were useful as novel metal-filled electrodes ( ). 

Finally, for practical reasons it is useful to classify polymeric materials according to where and how they are employed. A common subdivision is that into structural polymers and functional polymers. Structural polymers are characterized by - and are used because of - their good mechanical, thermal, and chemical properties. Hence, they are primarily used as construction materials in addition to or in place of metals, ceramics, or wood in applications like plastics, fibers, films, elastomers, foams, paints, and adhesives. Functional polymers, in contrast, have completely different property profiles, for example, special electrical, optical, or biological properties. They can assume specific chemical or physical functions in devices for microelectronic, biomedical applications, analytics, synthesis, cosmetics, or hygiene. 

There are several different approaches that are commonly used to determine particle size distributions in air. One of them, impaction, has been discussed earlier. Multistage impactors with different cut points are used extensively to obtain both mass and chemical composition data as a function of size for particles with diameters > 0.2 /xm. Others, including methods based on optical properties, electrical or aerodynamic mobility, and diffusion speeds, are described briefly in the following section. The condensation particle counter (CPC) is used as a detector in combination with some of these size-sorting methods. 

The physical properties of solvents greatly influence the choice of solvent for a particular application. The solvent should be liquid under the temperature and pressure conditions at which it is employed. Its thermodynamic properties, such as the density and vapor pressure, temperature and pressure coefficients, as well as the heat capacity and surface tension, and transport properties, such as viscosity, diffusion coefficient, and thermal conductivity, also need to be considered. Electrical, optical, and magnetic properties, such as the dipole moment, dielectric constant, refractive index, magnetic susceptibility, and electrical conductance are relevant, too. Furthermore, molecular... 

Man-made materials having superior mechanical, thermal, electrical, optical, and other desirable properties. 

The demand for advanced materials with superior mechanical, thermal, electrical, optical, magnetic, electro-optical, and electromagnetic properties is ever increasing. Most advanced materials, until recently, have been formed empirically by solid state methods. Further progress in the generation of advanced materials with preselected properties demands innovative chemical tailoring and, thus, a fundamental understanding of interactions and reactions at atomic, molecular, and supramolecular levels. 

The application of band theory to account for detailed electrical, optical and magnetic properties has so far had only limited success (28). Electronic conduction and optical absorption resulting in the onset of u.v.-visible opaqueness involve the transference of electrons from one ion to another, and it would therefore seem worth applying the principles of optical electronegativity to these problems. Any resulting correlations are expected to be of a much more qualitative nature than results given by applying band theory. 

A.H. Deutchman and R.J. Partyka (Beam Alloy Corporation observe, "Characterization and classification of thin diamond films depend both on advanced surface-analysis techniques capable of analyzing elemental composition and microstructure (morphology and crystallinity), and on measurement of macroscopic mechanical, electrical, optical and thermal properties. Because diamond films are very thin (I to 2 micrometers or less) and grain and crystal sizes are very small, scanning electron microscopy... 

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