Argon Gas Solubility in Styrene and Nitrogen, Oxygen and Argon Gas Solubilities in Methyl Methacrylate at (293 to 313) K and at Pressures up to 3.8 MPa

Dissolved oxygen is well known as an inhibitor in radical polymerization of vinyl monomer. Though the monomer solution is often saturated with argon or nitrogen to remove oxygen before polymer synthesis, there are few experimental data for the gas solubility. Thus, gas solubilities in solutions are reported for four binary systems. The solubilities of argon in styrene and nitrogen, oxygen or argon in methyl methacrylate (MMA) were measured at pressures up to 3.8 MPa, at 293, 303, 313 K. Gas solubilities at a given isotherm had linear pressure dependences, whereas Henry's constants decreased with increasing temperature. Argon solubilities in MMA were about 1.35 times larger than those in styrene. Nitrogen and oxygen solubilities in MMA were about 1.53 and 1.35 times larger than those for styrene. Experimental data could be correlated with the Peng-Robinson equation of state to within AARDs of 0.85% for argon in styrene and 1.31%, 1.53% and 0.81% for argon, nitrogen and oxygen solubilities in MMA, respectively. The data and the correlation allow analysis not only for Henry constants but also for gas concentration in monomer solution at given temperature and pressure.