Environmental Impact and Recycling

Under normal conditions PBT polymers can be stored for unlimited periods. Even at elevated temperatures (e.g. 40-45 °C) in air, and under the action of sunlight and weather, no decomposition reactions occur. PBT is not a hazardous material and it poses no risk to 

Carothers, Studies on polymerization and ring formation. I. An introduction to the general theory of condensation polymers, /. Am. Chem. Soc., 51 2548-2559,1929. 

Whinfield, J. T. Dickson, Polymeric linear terephthalic esters, US patent 2,465,319,1949. 

A route of chemical recycling by pyrolysis has been examined (71). The pyrolysis of COC was performed in a fluidized-bed reactor. Various parameters, such as pyrolysis temperature, fluidizing gas or residence time were varied. Under favorite conditions, the undesired tar fraction could be reduced to a minimum of around 10%. Up to 44% of valuable gases and 45% of aromatic light oils could be obtained at a pyrolysis temperature of 700°C. In general, nor-bornene was recovered only in traces. Thus, it is concluded that 2-norbomene is not sufficiently stable to resist the conditions of pyrolysis. Actually, a retro-Alder reaction occurs resulting in ethene and cyclopentadiene. 

Anderson and G.N. Merckling, Polymeric bicyclo-(2,2,l)-2-heptene, US Patent 2 721189, assigned to Du Pont, October 18,1955. 

Oshima, Y. Maruyama, N. Sakabe, K. Sawada, K. Ohkita, Y. Hashiguchi, T. Kanamori, and K. Kawahara, Composition of cyclic olefin addition copolymer and cross-linked material, US Patent 6639021, assigned to JSR Corporation (Tokyo, JP), October 28, 2003. 

Ishimaru, T. Tsutsui, A. Toyota, and N. Kashiwa, Cyclo-olefinic random copolymer, olefinic random copolymer, and process for producing cyclo-olefinic random copolymers, US Patent 5 008 356, assigned to Mitsui Petrochemical Industries, Ltd. (Tokyo, JP), April 16,1991. 

Kreuder and F. Osan, Cycloolefin copolymers and processes for their preparation, US Patent 5 756 623, assigned to Hoechst AG (DE) and Mitsui Petrochemical Ltd. (JP), May 26,1998. 

The oxidative polymerization of 2,6-dimethylphenol proceeds near room temperature. Moreover, the polymerization reaction does not create any leaving groups. From the aspect of green chemistry, water as a solvent for 

ACCUTECHTM ACLO Compounders Inc Glass fiber reinforced 

However, by using an excess of oxidant, the formation of TMDQ can be suppressed, even in an alkaline aqueous solution.Water soluble copper catalysts, which is a complex of CuCla x 2H2O and diethylenetri-amine-AW.iV. iV A -pentaacetic acid and other related complexes have been developed. Surfactants increase the yield of polymer. 

The products from the thermal degradation of Noryl GTX poly(phen-ylene oxide)-polyamide in air and in nitrogen have been identified and quantified. Ecotoxicologic testing of the products of pyrolysis with aquatic organisms indicated that in a fire, no greater harm than burned beech wood is to be expected when the fire-fighting water reaches aquatic ecosystems.  

Artificially prepared mixtures of poly(vinyl chloride), poly(carbon-ate), poly(oxymethylene) and PPE ean be separated by a flotation technique using common wetting agents like sodium lignin sulfonate, tannic acid, poly(oxyethylene), and saponin. The order of flotation response is given in Table 4.12. 

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As new polymer composites are considered, the issues of environmental impact and recycling become even more important. Metals have an advantage over polymer composites because an infrastructure exists for recycling them. However, work is progressing on developing more recyclable polymer composite systems. 

Environmental Impact and Recycling of Thermoplastic Copolyester Elastomers... 

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