Isobutene, thermodynamic properties

TABLE 2-228 Thermodynamic Properties of Isobutene (2-Methyl 1-Propene)... 

Hydrocarbons such as R290 have been in use for years because they have good thermodynamic and transport properties, as well as low cost and low toxicity [7], Large refrigeration plants in the petrochemical industry typically use R290. Household appliance manufacturers in Europe use isobutene (R600a) [7], In all, U.S. auto manufacturers do not want the potential liability issues associated with the use of a hydrocarbon as a potential refrigerant [7],... 

Auramine O and ethidium bromide interactions with hypercoiling olefin maleic acid copolymers have been used as probes to study the polyelectrolyte conformations.The two cationic dyes responded in fluorescence or in visible spectra to changes in conformation of aqueous solutions of maleic acid copolymers with ethylene, isobutene, 2-methyl-l-pentene, or 2,4,4-trimethyl-1-pentene. The fraction of bound auramine is very sensitive to the presence of polyelectrolyte compact coils and to changes in ionic strength and type of counterions. The fluorescence spectra of the ethidium bromide systems also depended on the structure of the compact coils. Dye properties are correlated with the viscosity and equilibrium thermodynamic data for the various copolymers. 

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