Chlorofluorocarbon alternatives

Chlorofluorocarbon alternatives must retain the attractive properties of chlorofluorocarbons, especially low toxicity, non-flammabihty, and good thermody-... 

Chlorofluorocarbon Alternatives. There still is no completely satisfactory propellant for use in the aerosol method of foam production. Chloroflu-orocarbons, still widely used, are harmful 10 atmospheric ozone and low molecular weight hydrocarbons, now popular, e g., in producing shaving cream, are explosive and promote the greenhouse effect. See also Fluorine. 

Process Economics Program Report SRI International. Menlo Park, CA, Isocyanates IE, Propylene Oxide 2E, Vinyl Chloride 5D, Terephthalic Acid and Dimethyl Terephthalate 9E, Phenol 22C, Xylene Separation 25C, BTX, Aromatics 30A, o-Xylene 34 A, m-Xylene 25 A, p-Xylene 93-3-4, Ethylbenzene/Styrene 33C, Phthalic Anhydride 34B, Glycerine and Intermediates 58, Aniline and Derivatives 76C, Bisphenol A and Phosgene 81, C1 Chlorinated Hydrocarbons 126, Chlorinated Solvent 48, Chlorofluorocarbon Alternatives 201, Reforming for BTX 129, Aromatics Processes 182 A, Propylene Oxide Derivatives 198, Acetaldehyde 24 A2, 91-1-3, Acetic Acid 37 B, Acetylene 16A, Adipic Acid 3 B, Ammonia 44 A, Caprolactam 7 C, Carbon Disulfide 171 A, Cumene 92-3-4, 22 B, 219, MDA 1 D, Ethanol 53 A, 85-2-4, Ethylene Dichloride/Vinyl Chloride 5 C, Formaldehyde 23 A, Hexamethylenediamine (HMDA) 31 B, Hydrogen Cyanide 76-3-4, Maleic Anhydride 46 C, Methane (Natural Gas) 191, Synthesis Gas 146, 148, 191 A, Methanol 148, 43 B, 93-2-2, Methyl Methacrylate 11 D, Nylon 6-41 B, Nylon 6,6-54 B, Ethylene/Propylene 29 A, Urea 56 A, Vinyl Acetate 15 A. 

Some physicians recommend epinephrine metered-dose inhalers as an alternative to epinephrine autoinjectors. While a few inhalations might relieve mild or moderate respiratory symptoms, for relief of life-threatening airway obstruction or shock, adults need to inhale 20-30 puffs and children need to inhale 10-20 puffs, which is hard to do [35]. Epinephrine metered-dose inhalers contain chlorofluorocarbon propellants. For environmental reasons, they might not be manufactured in the future. 

Table 5 Physicochemical Properties of Chlorofluorocarbon and Alternative Hydrofluorcarbon Propellants...

Toxicity of Alternatives to Chlorofluorocarbons HFC-134a and HCFC-123 (1996) Permissible Exposure Levels for Selected Military Fuel Vapors (1996)... 

Terrence Collins is the Thomas Lord Professor of Chemistry at Carnegie Mellon University who contends that the dangers of chlorine chemistry are not adequately addressed by either academe or industry, and alternatives to chlorine and chlorine processors must be pursued. He notes, Many serious pollution episodes are attributable to chlorine products and processes. This information also belongs in chemistry courses to help avoid related mistakes. Examples include dioxin-contaminated 2,4,5-T, extensively used as a peacetime herbicide and as a component of the Vietnam War s agent orange chlorofluorocarbons (CFCs) polychlorinated biphenyls (PCBs the pesticides aldrin, chlordane, dieldrin, DDT, endrin, heptachlor, hexachlorobenzene, lindane, mirex, and toxaphene pentachlorophe-... 

Snyder, G.N.Wogan, and G.S.Yost. 1998. Toxicity of alternatives to chlorofluorocarbons HFC-134a and HCFC-123. Inhal. Toxicol. 10 963-967. 

Chengelis, C.P. 1997. Epinephrine sensitivity of the canine heart A useful test. In R.Snyder, K.S.Bakshi, and B.M.Wagner, Abstracts of the Workshop on Toxicity of Alternatives to Chlorofluorocarbons. Inhal. Toxicol. 9 775—810. 

Smith, D.L., S.L.Aikman, L.J.Coulby, J.Sutcliffe, and BJ.O Conner. 1994. The attenuation of methacholine-induced bronchoconstriction by salmeterol comparison between an alternative metered dose inhaler propellant GR106642X and chlorofluorocarbons 11 and 12. Eur. Resp. J. 7 (Suppl. 18) 318s. 

Taggart, S.C.O., A.Custovic, D.H.Richards, and A.Woodcock 1994. An alternative metered dose inhaler propellant GR106642X comparison to chlorofluorocarbon 11 and 12 in the attenuation of histamine-induced bronchoconstriction by salbutamol. Eur. Resp. J. (Suppl. 18) 400s. 

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