Greenhouse gases chlorofluorocarbons

Global Warming and increased Climatic Variability due to Greenhouse Gas (GHG) Accumulation in the Atmosphere and Increased Radiation due to Ozone Depletion by Chlorofluorocarbons (CFC). 

Amorphous fluoropolymers have many applications in the areas of advanced materials where they are used in applications requiring thermal and chemical resistance. Their manufacture is hindered by their low solubility in many solvents. Many fluoropolymerizations cannot be carried out in hydrocarbon solvents because the radical abstraction of hydrogen atoms leads to detrimental side reactions. Chlorofluorocarbons (CFCs) were thus commonly used, but their use is now strictly controlled due to their ozone depleting and greenhouse gas properties. Supercritical carbon dioxide is a very attractive alternative to CFCs and it has been shown that amorphous fluoropolymers can be synthesized by... 

Under the terms of the Montreal Protocol, aimed at reducing damage to the ozone layer, the use of chlorofluorocarbons has been prohibited since January 1996. Since difluoroethane does not contain chlorine, there are no environmental controls on the use of this material as a propellant, since it does not deplete the ozone layer and is not a greenhouse gas. 

Coalition for Environmentally Responsive Economies chlorofluorocarbon - a VOC which is both ozone-depleting and a greenhouse gas... 

CO2, along with nitrous oxide, methane, chlorofluorocarbons, tropospheric ozone, and water vapor is a greenhouse gas. With the exception of water vapor, the concentration of all these gases is controlled more or less directly by human activities. CO2 is the most important greenhouse gas because it has an atmospheric life of about 100 years and therefore builds up in the atmosphere over long periods. While the preindustrial CO2 concentration was about 280 ppmv, its present concentration has increased 32% since preindustrial times to reach 370 ppmv today. Half of the increase has been since 1965 . 

The use of supercritical fluids represents a way to replace conventional solvents. Recall that a supercritical fluid is an unusual state of matter that has properties of both a gas and a liquid, qqo (Section 11.4) Water and carbon dioxide are the two most popular choices as supercritical fluid solvents. One recently developed industrial process, for example, replaces chlorofluorocarbon solvents with liquid or supercritical CO2 in the production of polytetrafluoroethylene ([CF2CF2] , sold as Teflon ). Though CO2 is a greenhouse gas, no new CO2 need be manufactured for use as a supercritical fluid solvent. 

The effects that numerous trace gases have on our atmosphere, and associated with it our climate, have been studied extensively. Probably the most prominent of these are the greenhouse gas CO2 and O3-destroying chlorofluorocarbons (CFCs). But other trace gases associated with the two aforementioned effects also receive high attention, namely CH4 and nitrogen oxides. 

It is important to prevent the release of greenhouse gases other than carbon dioxide, especially ultrastable volatile compounds that have a high greenhouse gas potential. An excellent example of green chemistry has been the replacement of chlorofluorocarbons (CFCs) (Freons such as... 

CO2 is not the only greenhouse gas. Several gases are even stronger infrared absorbers—specifically, methane (CH4), ozone (O3), nitrous oxide (N2O), and chlorofluorocarbons (CFCs). Furthermore, atmospheric concentrations of some of these gases have been growing at a faster rate than that of CO2. No... 

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