Polymers, environmentally responsive

This chapter looks at the particular question of polymers and the environment. A book on the science of polymers ought to give some consideration to this issue because of the growing concern about the effect of discarded plastic on the quality of life on Earth. If we are to produce and use polymers in ways that are more environmentally responsible (and society will increasingly demand that we do) then there will be new technical challenges to face. One purpose of this chapter is to indicate what some of these challenges might be. 

Geckeler, K, E, Soluble Polymer Supports for Liquid-Phase Synthesis. VoL 121, pp. 31-80. Gehrke, S, H. Synthesis, Equilibrium Swelling, Kinetics Permeability and Applications of Environmentally Responsive Gels. Vol. 110, pp. 81 -144. de GenneSy P.-G> Flexible Polymers in Nanopores. VoL 138, pp. 91-106. 

SH Gehrke. Synthesis, equilibrium swelling, kinetics, permeability and applications of environmentally responsive gels. Adv Polym Sci 110 81-144, 1993. 

Fig. 4. Cyclic change of pH, T, or ionic strength (/) leads to abrupt changes in the drug release rates at certain time intervals in some environmentally responsive polymers.

Kizhakkedathu JN, Norris-Jones R, Brooks DE. Synthesis of well-defined environmentally responsive polymer brushes by aqueous ATRP. Macromolecules 2004 37 734-743. 

Minko S, Stamm M, Goreshnik E, Usov D, Sidorenko A. Environmentally responsive polymer brush layers for switchable surface properties. Pol3mi Mater Sci Eng 2000 83 533-534. 

Zhu C, Hard C, Lin C, Gitsov I. Novel materials for bioanalytical and biomedical applications environmental response and binding/telease capabilities of amphiphilic hydrogels with shape-persistent dendritic junctions. J Polym Sci Part A Polym Chem 2005 43 4017-4029. 

Supercritical carbon dioxide has been used as a dispersing medium for the manufacture and processing of polymeric materials. The process allows for the synthesis of high molar mass acrylic polymers in the form of micrometer-sized particles with a narrow size distribution. This procedure represents an environmentally responsible alternative to aqueous and organic dispersing media for heterogeneous dispersion polymerizations (Fox, 1994). 

Garnweitner, G., Smarsly, B., Assink, R., Ruland, W., Bond, E., and Brinker, C. J. Self-assembly of an environmentally responsive polymer/silica nanocomposite, JACS (2003), 125, 5626-5627. 

Because CDs are nontoxic, biodegradable, and bioabsorbable, they may be used in medical applications, as well as providing for the fabrication of more environmentally responsible polymer materials. In this report we have summarized almost exclusively our own recent studies employing the cyclic starch derivatives called cyclodextrins to both nanostructure and functionalize polymer materials. Lest the reader gets the erroneous impression that our studies have been carried out in isolation, we refer to a recent review [120], and a summary [121], describing related... 

Joseph M. DeSimone (BCST Liaison) is William R. Kenan, Jr., Distinguished Professor of Chemistry and Chemical Engineering at North Carolina State University and the University of North Carolina. He is also director of the National Science Foundation Science and Technology Center for Environmentally Responsible Solvents and Processes. He received his B.S. in chemistry form Ursinus College and his Ph.D. in chemistry from Virginia Polytechnic Institute and State University. His areas of interest include polymer synthesis in supercritical fluids, surfactant design for applications in interfacial chemistry, and polymer synthesis and processing—from fundamental aspects of chemical systems to the most efficient and environmentally friendly ways to manufacture polymers and polymer products. 

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