Polymers theory

M. W. AT2rs1, Attenuated Total Reflectance Spectroscopy of Polymers Theory and Practice, American Chemical Society, Washington, D.C., 1996. 

Mana.s-Zioczower, 1., andTadmor, Z. (1993). Mixing and Compounding of Polymers Theory and Practice, p. 561, Hanser-Gardner Pub. 

This leads us to a cracial point in thinking about micro-macro relations The closeness of the linkage between the microscopic and the macroscopic view of the world. As the example of the macromolecnlar theory shows, the same observations can be explained by dilferent theories. In other words, the cotmection between phenomena and scientific theories is not an nnambiguous one. Although one theory fits better with the observed facts than the other, the constraction of the model always remains a theoretical construction to explain phenomena. On the other hand, theories can influence the macroscopic reality as well. The polymer theory, for example, can be used to design polymers. 

In summary, the historical material about polymers was not as fraitful in the way we used it. Both theories seemed to be useful and convincing for the students. Obviously, both theories are complex and could indeed explain the observed phenomena. The need for modem techniques of analyses becomes obvious, which have also been the important step in the history of polymer theories. Additionally, these results might also show that students are not used to evaluating and comparing different theories. 

McLeish, T.C.B. et al. Dynamics of entangled H-polymers Theory, rheology, and neutron scattering. Macromolecules, 32, 6734, 1999. 

Freire, /. /. Conformational Properties of Branched Polymers Theory and Simulations. VoL 143, pp. 35-112. 

Manas-Zloczower, I., Dispersive mixing of solid additives, in Mixing and Compounding of Polymers—Theory and Practice. (I. Manas-Zloczower and Z. Tadmor, Ed.) Hanser Publishers, Munich, 1994, pp. 55-83. 

In addition to temperature and concentration, diffusion in polymers can be influenced by the penetrant size, polymer molecular weight, and polymer morphology factors such as crystallinity and cross-linking density. These factors render the prediction of the penetrant diffusion coefficient a rather complex task. However, in simpler systems such as non-cross-linked amorphous polymers, theories have been developed to predict the mutual diffusion coefficient with various degrees of success [12-19], Among these, the most notable are the free volume theories [12,17], In the following subsection, these free volume based theories are introduced to illustrate the principles involved. 

The trial-by-fire methods of science, however, sidetracked the linear development of high polymer theory, for the theory was swept up by the development of the association theory of collodal particles at about the turn of the century. The peculiar and hard to understand chemical and physical behavior of polymers had, on occasions, lead to the suggestion that unusual or special forces were involved in their formation. In order to explain the forces, workers turned to the work of Thomas Graham. 

Organic Chemistry, X-ray Crystallography, and Modern Polymer Theory... 

Polanyi s interpretation (47) was the second important step in the resolution of modern polymer theory for it marked the beginning of the use of X-ray diffraction in the investigation of polymer structure. Polanyi s conclusion was... 

In reviewing, the development of a useful polymer theory was a prerequisite for the expansion in research, and explosion in use, of these unique materials. The development occured in several distinct phases. It was marked by several landmark events and papers, and it can claim its conception as the product of remarkably few workers. It is doubtful that the army of scientists, technicians, and engineers involved in polymer research, much less the lay recipients of the wealth and benefits of the resultant technology, realize the impact that so few have had on their lives. We are reminded in a time of diminishing influence of the individual, that singular contributions have been, and should continue to be, an important part of science. 

Dusek, K., Networks from telechelic polymers theory and application to polyurethanes, in Goethals, E. J. (ed.), Telechelic Polymers Synthesis and Applications, CRC Press, Boca Raton, FL, (1989), pp. 289-360. 

Conformational Properties of Branched Polymers Theory and Simulations... 

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