High-pressure phase behavior of the quaternary system (carbon dioxide plus dichloromethane plus ε-caprolactone plus poly(ε-caprolactone): Experimental data and PC-SAFT modeling

The phase behavior of the system containing carbon dioxide + dichloromethane + epsilon- caprolactone + poly(epsilon-caprolactone) was studied in order to get important information to understand the polymerization reaction in a high-pressure system. The experiments were performed using a variable-volume view cell over the temperature range from 323.15 to 353.15 K. The mass ratio between dichloromethane: (epsilon- caprolactone + poly(epsilon-caprolactone)) mixture was kept fixed at 1:1 with different poly(epsilon-caprolactone) mass fractions (reaction conversion) from 0.0 up 15.0 wt%. The mass composition of supercritical carbon dioxide varied in relation to the dichloromethane + epsilon- caprolactone + poly(epsilon- caprolactone) mixture from 60.0 to 77.5 wt% on dichloromethane free basis. Phase transitions of vapor liquid bubble point type (VLE-BP) and liquid-liquid (LLE) were verified and lower critical solution temperature (LCST) behavior in P-W and P-T diagrams was observed. The experimental results were modeled using the PC-SAFT EoS, providing a positive representation of the experimental phase equilibrium data. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The phase behavior of a system containing carbon dioxide, dichloromethane, epsilon-caprolactone, and poly(epsilon-caprolactone) was studied, revealing vapor-liquid bubble point type and liquid-liquid phase transitions. The experiments were performed using a variable-volume view cell over a temperature range, and the results were modeled using the PC-SAFT EoS with positive representation of the experimental phase equilibrium data.