Plastics characterization

Phototubes, multiplier, 56-59, 222 Placement error, 285-287 Planck s constant, 7, 8 Plastics, characterization by absorptiometry, 78, 79 Plateau, characteristic, 60 Platinum, determination by x-ray emission spectrography, 161, 328 L peaks, measured by Bragg, 25, 26, 35 L spectra, 35... 

This book provides an overview of the science and technology of pyrolysis of waste plastics. The book will describe the types of plastics that are suitable for pyrolysis recycling, the mechanism of pyrolytic degradation of various plastics, characterization of the pyrolysis products and details of commercially mature pyrolysis technologies. 

Thermosetting polymers (also called thermosets) are a family of plastics characterized by the fact that they are formed starting from a liquid solution that irreversibly leads to a solid material during a heating step. In this sense, they exhibit an opposite behavior than the one of thermoplastic polymers that, with some exceptions, show a reversible solid-to-liquid transition when heated to a convenient temperature. Although the irreversible liquid-to-solid transition can be also produced by other means such as UV or electron beam irradiation, the resulting products are also called thermosetting polymers. The process by which the initial liquid solution is transformed into a solid is usually known as the cure of the material. 

The ease of deformation called plasticity characterizes the unvulcanized rubber compound, and causes the highly plastic rubber to flow easily. Viscosity is the resistance to plastic deformation or flow and, hence, the inverse of plasticity. Unvulcanized rubbers are not totally viscous but exhibit some elastic behavior. Rubber does not exhibit Newtonian flow as the shear rate is not proportional to the shear stress. Moreover, measurements of flow properties should be made at the shear rate of interest. 

Keywords Characteristics of Plastics, Characterization, Classification, Economic data. Environmental Polymer Engineering... 

Cell collapse n. A defeat in foamed plastics characterized by slumping and cratered surfaces, with the internal cells resembling a stack of leaflets when viewed in cross section under a microscope. The condition is caused by tearing of the cell walls, weakened by plasticization or other mechanism. 

Diundecyl phthalate (DUP) n. A plasticizer characterized by low volatility and good low-temperature properties compared to other phthalates. 

Polyester plasticizer n. Any of a broad class of plasticizers characterized by having many ester groups in each molecule. They are synthesized from three components (1) A dibasic acid such as adipic, azelaic, lauric, or sebacic acid. (2) A glycol (dihydric alcohol). (3) A monofunctional chain terminator such as a monobasic acid. Molecular weights are low - from 500 to 5,000. Polyester plasticizers are noted for their permanence and resistance to extraction. 

In particular, we are interested in the case of finite strain plasticity characterized by the multiplicative decomposition F = F F of the deformation gradient in an elastic and plastic part see Armero (2006) and references therein. The stresses are then given in terms of an elastic potential W" C") for C = F F as... 

Cell Collapse n A defeat in foamed plastics characterized by slumping and cratered surfaces, with the internal... 

Polyester Plasticizer Any of a broad class of plasticizers characterized by having many ester groups in each... 

The concept of chemical resistance in plastics characterizes the resistance of that plastic material to aggressive media, radiation, and long-term mechanical loads. However, the concept of chemical resistance often raises objections. It has been proposed to use the neutral term behavior toward... instead. However, the term chemical resistance is wide-spread and in constant general use, although it lacks univocal conceptual content, since the demands made on plastics differ from one case to another. Thus the concept of chemical resistance should not be applied to a material itself, but to finished parts made from polymers, having a particular intended use, such as polypropylene piping for waste-water from buildings [13]. 

Keywords Quick dissolving films, wafers, polymeric blends, plasticizers, characterization, morphological study, dosage forms, testing, pharmaceutical science, oral dehvery, buccal delivery... 

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