Polymers environmental benefits

The development of a rechargeable polymer battery is being pursued worldwide. Its attraction lies in the specific weight of polymers, which is considerably lower than that of ordinary inorganic materials, as well as potential environmental benefits. In principle there are three different types of battery. The active polymer electrode can be used either as cathode (cell types 1, 2), or as anode (cell type 3), or as both cathode and anode (cell type 4) (Fig. 14). As the most common polymer materials are usually only oxidizable, recent research has concentrated on developing cells with a polymer cathode and a metal anode. 

One of the applications for hydrogen is for Polymer Electrolyte Membrane (PEM) fuel cells. As mentioned earlier, one application is a hydrogen fuelled hybrid fuel cell / ultra-capacitor transit bus program where significant energy efficiencies can be demonstrated. Another commercial application is for fuel cell powered forklifts and other such fleet applications that requires mobile electrical power with the additional environmental benefits this system provides. Other commercial applications being developed by Canadian industry is for remote back-up power such as the telecommunications industry and for portable fuel cell systems. 

The shift from bio-based specialties to commodities is already visible in the marketplace with biopolymers made from corn. The first example is NatureWorks from Cargill, which is made from corn sugar-derived lactic acid. As in the biochemicals examples described above, the environmental benefits are eye-opening NatureWorks already requires 25 to 55 percent less fossil resources, and it is planned to replace fossil resources completely in the next four to six years (Euro-paBio and McKinsey Company, 2003). Other high-potential biomaterials are a polymer based on 1,3-propanediol from DuPont and Genencor (Sorona ) and... 

Compressed liquid or supercritical carbon dioxide has been recognized as a useful alternative reaction medium for radical and ionic polymerization reactions (see Chapter 4.5). Many of the benefits associated with the use of SCCO2 in these processes apply equally well to polymerizations relying on a metal complex as the chain-carrying species. However, the solubility of the metal catalyst and hence the controlled initiation of chain growth add to the complexity of the systems under study. Furthermore, many of the environmental benefits would be diminished if subsequent conventional purification steps were needed to remove the metal from the polymer. Nevertheless, the interest in metal-catalyzed polymerizations is increasing, and some promising systems have been described. 

N.S. Allen, M. Edge, 1. Verran, 1. Stratton, 1. Maltby, C. Bygott, Photocatal3dic titania based surfaces Environmental benefits . Polymer Degradation and Stability, 93,1632-1646, (2008). 

Regarding the high number of available data from literature, one can conclude that important progress has already been achieved in terms of combining the environmental benefit of future-oriented bio-polyesters with economic viability of their production. This should finally facilitate the decision of responsible policymakers from various waste-generating industrial branches and from polymer industry to break new ground in sustainable production. 

In general, supercritical carbon dioxide can be regarded as a viable alternative solvent for polymer processes. Besides the obviously environmental benefits, supercritical carbon dioxide has also desirable physical and chemical properties... 

The S5mthesis, processing, and technology of renewable polymers has been reviewed (2-9). Further, the state-of-the-art for food packaging applications has been reviewed (10-12). Using biomass for the production of new polymers can have both economic and environmental benefits (13). 

The use of polymers in automobiles has increased dramatically over the last 100 years. Particularly significant gains were made within the last two decades. Figure 17.1 shows the dramatic increase in the polymer content in a typical vehicle over recent years. These materials provide increased comfort, better aesthetics, safety enhancements, and environmental benefits over the conventional materials they replaced. This chapter will discuss where these materials are used and the environmental benefits they provide in such applications. 

Cellulose, the most abundant renewable and biodegradable polymer, is the promising feedstock for the production of chemicals for their appUcatimis in various industries. Annual production of cellulose in nature is estimated to be lO"—10 t in two forms, partially in a pure form, for example seed hairs of the cotton plant, but mostly as hemicelluloses in cell wall of woody plants (Klenun et al. 1998). The versatility of cellulose has been reevaluated as a useful structural and functional material. The environmental benefits of ceUulosics have become even more apparent (Hon 1996a). Cellulose is revered as a constmction material, mainly in the form of intact wood but also in the form of natural textile fibers like cotton or flax, or in the form of paper and board. The value of cellulose is also recognized as a versatile starting material for subsequent chemical transformation in production of artificial ceUulose-based threads and films as well as of a variety of cellulose derivatives for their utilization in several industries such as food, printing, cosmetic, oil well drilling, textile, pharmaceutical, etc. and domestic life. 

Patel M (2003) Do biopolymers fulfill our expectations concerning environmental benefits In Chiellini E, Solaro R (eds) Biodegradable polymers and plastics. Kluwer/Plenum, New York Poole AJ, Church JS, Huson MG (2009) Environmentally sustainable fibers from regenerated protein. Biomacromolecules 10 1-8... 

Suspension polymerization is a very important method of polymerization, especially used in free radical polymerization. The benefit of suspension polymerization over bulk polymerization includes ease of temperature (and hence reaction) control and the formation of a directly usable product. The particles formed can in many cases be used directly as beads for ion exchange resins or chromatography columns or as bulk polymer pellets like common polystyrene and polystyrene copolymers. In addition, there are considerable environmental benefits of performing industrial polymerizations in aqueous media. 

The development of the synthetic polymer industry has been related more to the economic advantages that the materials bring rather than their environmental benefit, yet these economic considerations have led to plastics making a significant beneficial impact on the environment. For example ... 

Allen NS, Edge M, Verran J, Stratton M, Maltby J, Bygott C. Photocatalytic titania based surfaces environmental benefits. Polym Degrad Stab 2008 93 1632-46. 

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