| Perfluoroelastomers is excellent in physical property and chemical resistance,moreover the range of its applied temperature is wide(-45～316℃), so not only it iswidely applied in chemical industry, petroleum, manufactory, machinemanufacturing, aviation and spaceflight, electronic instrument, shipbuilding andvarious vehicle, but also it can be fit for a lot of severe rugged environment.Perfluoromethyl vinyl ether is the first monomer for perfluoroelastomers, andpotentially become a new important monomer for modified perfluoroelastomers andmodified fluoroplastics.For the moment perfluoromethyl vinyl ether is produced only in ChenguangResearch Institute of Chemical Industry. But the data of physical property forperfluoromethyl vinyl ether are very lack, so our lab had been built a set of devicefor the measurement of low-temperature vapor-liquid equilibria, which consists of athermostatic bath, a equilibrium cell, a electromagnetic recirculation pump, vacuum,the units for temperature measurement or pressure measurement, gas chromatogram,etc. Internal volume of the equilibrium cell is about 200ml. The temperature wasmeasured by precise PT100 thermal resistance (uncertainty of±0.01K), and thepressure was measured by mercury differential manometer (uncertainty of±0.013kPa) or high-precision pressure sensor(accuracy of 0.1). The device wasverified by chlorotrifluoroethylene for the measurement of vapor pressure and byC2H6+C3H8 system for the measurement of vapor-liquid equilibrium. The differencebetween experimental data and the data in the literature is very little, which approvesthat the device is reliable. By static method the vapor pressure for perfluoromethylvinyl ether was measured at the temperature range of (248.15～338.35)K. Theexperimental vapor pressure data was correlated with Antoine equation. Based on the Antoine equation the boiling point of perfluoromethyl vinyl ether was calculated,whose value was 247.74K, and based on the Clapeyron-Clausius equation theaverage mole heat of vaporization△vapHm was calculated, whose value was20.7kJ/mol. The vapor-liquid equilibrium of perfluoromethyl vinyl ether andchlorotrifluoroethylene system was measured at temperatures of (267.67, 272.54,277.45, 282.62)K. The experimental vapor-liquid equilibrium data was correlatedwith Margules equation, Wilson equation, and NTRL equation, and the experimentalresults agree well with the calculated data. The compositions of vapor and liquidphases were analyzed by gas chromatography, and the uncertainty was±0.001 inmole fraction.The measurement of these data has important significance for rectification designand production operation. The vapor pressure of perfluoromethyl vinyl ether wasIn'st measured completely, and the VLE data of perfluoromethyl vinyl ether andchlorotrifluoroethylene system has not been reported previously in the literature.
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