Organic chemistry natural polymers

REACTION MECHANISMS IN ENVIRONMENTAL ORGANIC CHEMISTRY Humic Polymers and Natural Waters... 

Dendrimers are by their nature complex materials and their study interserts the research fields of both organic chemistry and polymer chemistry. With a growing interest in finding and utilizing dendrimers for advanced applications, especially in... 

Government and University Research. As an industry, plastics engineering has traditionally been driven by the large profits that result from patented processes and materials. As natural offshoots of organic chemistry, however, polymer science and plastics engineering have developed into major fields of study at the academic level. Research into new and improved polymerization reactions and methods has been conducted at many major universities and colleges, and some institutions specialize exclusively in polymer research. 

The preparation of polymers in this early phase of synthetic organic chemistry seems not to have been uncommon. It must not be concluded from the above citations, however, that their polymeric nature usually was comprehended. In the vast majority of instances this was not the case. 

In February 1928, Wallace H. Carothers (Figure 1.2), then an Instructor at Harvard, joined du Pont at Wilmington to set up a fundamental research group in organic chemistry. One of the first topics he chose was the nature of polymers, which he proposed to study by using synthetic methods. He intended to build up some very large molecules by simple and definite reactions in such a way that... 

Polymer science is a fairly new field in the natural sciences. In the first 15 years it was certainly no more than a special subject of organic chemistry, but around 1940 this new topic started to spread its roots into all the traditional fields of science. The immense influence on biochemistry and biophysics is well known, and our present understanding of the molecular basis of biological processes is inconceivable without Staudinger s pioneering work1,21. 

J Lipid Res J Med Chem J Mol Catal I Nat Prod J Nucl Med I Pharm Sci I Photochem J Phys Chem J Phys Org Chem J Polym Sci, Polym Chem Ed J Prakt Chem J Russ Phys Chem Soc J Sci Ind Res B Journal of Lipid Research Journal of Medicinal Chemistry Journal of Molecular Catalysis Journal of Natural Products Journal of Nuclear Medicine Journal of Pharmaceutical Sciences Journal of Photochemistry Journal of Physical Chemistry Journal of Physical Organic Chemistry Journal of Polymer Science Polymer Chemistry Edition Journal fur Praktische Chemie Journal of the Russian Physical Chemical Society Journal of Scientific and Industrial Research. Part B Physical Sciences... 

We have shown how the band structure of photoexcited semiconductor particles makes them effective oxidation catalysts. Because of the heterogeneous nature of the photoactivation, selective chemistry can ensue from preferential adsorption, from directed reactivity between adsorbed reactive intermediates, and from the restriction of ECE processes to one electron routes. The extension of these experiments to catalyze chemical reductions and to address heterogeneous redox reactions of biologically important molecules should be straightforward. In fact, the use of surface-modified powders coated with chiral polymers has recently been reputed to cause asymmetric induction at prochiral redox centers. As more semiconductor powders become routinely available, the importance of these photocatalysts to organic chemistry is bound to increase. 

Many of the considerations discussed above in connection with organic chemistry are, of course, also valid for polymer technology. The aspects to be discussed here are solvents for polymers, used in such materials as paints and lacquers, and media for the polymerization reaction. A final deliberation pertains to certain biopolymers and polyelectrolytes, where the natural solvent is water, but where other solvents may also be useful in their study. 

A second feature, also noted earlier, is the interest of many living chemists in the history of their science, often manifested in some autobiographical form. A third characteristic of many of the works cited below, also of general occurrence, is the strong emphasis on obviously useful organic chemistry. There is, therefore, much activity in the history of medical chemistry (Chapter 8) and also in the studies of natural products and of synthesis that must precede any usefulness. Polymers come well to the fore. 

Finally, we shall return to the problem of the naming of the discipline. As we have seen, Staudinger named his field macromolecular chemistry to designate it as a new organic chemistry. Throughout his career, he did not venture to use the name macromolecular science. But, as the field acquired an interdisciplinary character, the latter name was adopted in some quarters as a natural extension of macromolecular chemistry. [45] Polymer science, which had the connotation of interdisciplinarity from the outset of its usage, had been employed by Mark and his followers decades before macromolecular science came into use. 

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