Chemical Analysis for Polymer Engineers

Tab. 20.1. Objectives of the two types of chemical analysis for polymer reaction engineering.

Dynamic mechanical tests have been widely applied in the viscoelastic analysis of polymers and other materials. The reason for this has been the technical simplicity of the method and the low tensions and deformations used. The response of materials to dynamic perturbation fields provides information concerning the moduli and the compliances for storage and loss. Dynamic properties are of considerable interest when they are analyzed as a function of both frequency and temperature. They permit the evaluation of the energy dissipated per cycle and also provide information concerning the structure of the material, phase transitions, chemical reactions, and other technical properties, such as fatigue or the resistance to impact. Of particular relevance are the applications in the field of the isolation of vibrations in mechanical engineering. The dynamic measurements are a... 

Laser desorption methods (such as LD-ITMS) are indicated as cost-saving real-time techniques for the near future. In a single laser shot, the LDI technique coupled with Fourier-transform mass spectrometry (FTMS) can provide detailed chemical information on the polymeric molecular structure, and is a tool for direct determination of additives and contaminants in polymers. This offers new analytical capabilities to solve problems in research, development, engineering, production, technical support, competitor product analysis, and defect analysis. Laser desorption techniques are limited to surface analysis and do not allow quantitation, but exhibit superior analyte selectivity. 

The engineering analysis and design of these operations addresses questions which are different than those addressed in connection with the shaping operations. This is illustrated in Fig. 1 which is a flow sheet, cited by Nichols and Kheradi (1982), for the continuous conversion of latex in the manufacture of acrylonitrile-butadiene-styrene (ABS). In this process three of the nonshaping operations are shown (1) a chemical reaction (coagulation) (2) a liquid-liquid extraction operation which involves a molten polymer and water and (3) a vapor-liquid stripping operation which involves the removal of a volatile component from the molten polymer. The analysis and design around the devolatilization section, for example, would deal with such questions as how the exit concentration of... 

Replete with problem sets and a solutions manual for instructors this textbook is recommended for undergraduate and graduate students in chemical engineering and polymer and materials engineering and science. It will also prove invaluable for industry professionals as a fundamental polymer processing analysis and synthesis reference. 

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