Free-Radical Polymerization of Styrene in CO2 /Ethanol Mixed Supercritical Fluid

Abstract

The free‐radical polymerization of styrene has been studied in CO2/ethanol mixed supercritical fluid. Depending on the experimental conditions, yields varied from low to fairly good (around 60%). The polymers exhibited molar masses ranging from 5 000 to 26 000 g/mol. The results obtained were compared with those generated in the presence of mesitylene or pure ethanol used as solvent. In particular, it was observed that the thermal polymerization of styrene in the supercritical fluids or in ethanol was somewhat inhibited as compared to that occurring in mesitylene. Indeed, almost no thermal polymerization could be observed in these conditions.

Relation between Volume Expansion and Hydrogen Bond Networks for CO2−Alcohol Mixtures at 40 °C

“…There has been an increase in the number of reports for CO 2 -expanded liquid mixtures. The phenomenon of liquid-phase volume expansion resulting from the addition of CO 2 to many organic solvents has been utilized for industrial processes. − CO 2 -expanded liquids provide the substitution of the organic solvents. Further development of CO 2 -expanded liquid requires accurate experimental data.…”

MD Simulation of the Self-diffusion Coefficient and Dielectric Properties of Expanded Liquids—I. Methanol and Carbon Dioxide Mixtures

“…Especially near the mixture critical point, methanol can be considered to be in an expanded state. Expanded liquids have much attention as solvents for high performance liquid chromatography [2], metal ion extraction [3], polymerizations [4] and polymer coating [5] due to the highly adjustable properties such as viscosity and solubility.…”

Molecular motility and affinity of expanded carbon dioxide+ketone systems analyzed by molecular dynamics simulations

“…However, at compressed condition at near room temperatures, CO 2 liberally dissolves in organic compounds [1][2][3], and organic compounds can be considered to be in an expanded state that is referred to as a CO 2 -expanded liquid. CO 2 -expanded liquids have been used for supercritical antisolvent recrystallization (SAS) [4][5][6][7] and applied to reactions [8], crystallization [9], and polymerizations [10]. Therefore, it is very important to know their physical properties (density, diffusivity, dielectric constant, etc.)…”