Title: HFC-134a
CAS Registry Number: 811-97-2
CAS Name: 1,1,1,2-Tetrafluoroethane
Additional Names: 1,2,2,2-tetrafluoroethane; refrigerant 134a; R134a; HFA-134a
Molecular Formula: C2H2F4
Molecular Weight: 102.03
Percent Composition: C 23.54%, H 1.98%, F 74.48%
Line Formula: F3CCH2F
Literature References: Environmentally acceptable alternative to chlorofluorocarbons used as a refrigerant, solvent and propellant. Overview of commercial development: L. E. Manzer, Catal. Today 13, 13-22 (1992). General description: D. Mayer et al., Jt. Assess. Commod. Chem. 1995, 1-36. Dielectric data: Y. Tanaka et al., Fluid Phase Equilib. 80, 107 (1992); pressure-volume data: M.-S. Zhu et al., ibid. 149. Density measurements of HFC-134a and its mixtures: P. S. Fialho et al., High Temp. - High Pressures 27/28, 569 (1996). Chemistry of atmospheric degradation: J. Sehested, T. J. Wallington, Environ. Sci. Technol. 27, 146 (1993). Catalytic synthesis and kinetics: F. H. Ribeiro et al., Catal. Lett. 45, 149 (1997). Review of catalytic synthesis: L. E. Manzer, V. N. M. Rao, Adv. Catal. 39, 329-350 (1993). Review of toxicology: D. J. Alexander, S. E. Libretto, Hum. Exp. Toxicol. 14, 715-720 (1995). Review of viscosity measurements: C. M. B. Oliveira, W. A. Wakeham, High Temp. - High Pressures 27/28, 91-98 (1996). Review of use as refrigerant: E. Preisegger, R. Henrici, Int. J. Refrig. 15, 326-331 (1992); as blowing agent: R. E. Morgan et al., UTECH Asia '97, Int. Polyurethanes Conf. Exhib. Asia-Pac. (Crain Communications, London, UK, 1997) pp 1-8.
Properties: Non-flammable, colorless gas with a faint ethereal odor. bp1atm -26.15°. mp -101°. Critical temp: 101.05°. Critical pressure: 40.64 atm. Critical density: 0.508 g/cm3. d25 1.202. log P (octanol/water): 1.06. Heat of vaporization (0°): 47.52 cal/g. Viscosity (25°): 0.204 cP. Surface tension (25°): 8.466 dynes/cm. LC50 (15 min) in rats: 3400000 mg/m3 (>800000 ppm); LC50 (4 hr) in rats: 2215000 mg/m3 (>500000 ppm) (Mayer).
Melting point: mp -101°
Boiling point: bp1atm -26.15°
Log P: log P (octanol/water): 1.06
Density: Critical density: 0.508 g/cm3; d25 1.202
Toxicity data: LC50 (15 min) in rats: 3400000 mg/m3 (>800000 ppm); LC50 (4 hr) in rats: 2215000 mg/m3 (>500000 ppm) (Mayer)
Use: Refrigerant, propellant for pharmaceuticals; blowing agent for foams. |