Interaction between supercritical carbon dioxide-cosolvent and poly(vinyl acetate)

HU Dongdong1 BAO Lei1 LIU Tao1 LANG Meidong2 ZHAO Ling1

(1.State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, China 200237)
(2.School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, China 200237)

【Abstract】The effect of cosolvents (ethanol, acetone, n-heptane) on the supercritical CO2 system were evaluated through the multi-scale molecular modeling and dissolution behavior measurement, which might improve the solvent-solvent and solvent-solute interactions and enhance the compatibility with polymer. The ab initio calculation showed that the interaction between ethanol and CO2 was the strongest one, followed by those of CO2 with acetone and n-heptane. The molecular dynamics simulations indicated that ethanol significantly increased the solubility parameter of solvent, and the interaction of supercritical CO2–ethanol with PVAc chain was stronger than those of the other two at the same cosolvent content, which was helpful to improve the compatibility between PVAc and the solvent. The interaction between ethanol and CO2 was the strongest due to the bigger solubility parameter of ethanol and the obvious hydrogen bond between ethanol and CO2. The cloud point experiments confirmed that ethanol was the most effective to reduce the cloud point pressure of PVAc. The addition of cosolvent enhanced the compatibility of supercritical CO2 system with PVAc, and the solubility of PVAc in supercritical CO2–cosolvent increased with the mole fraction of cosolvent.

【Keywords】 carbon dioxide; cosolvent; poly(vinyl acetate) ; solubility; molecular simulation;

【DOI】

【Funds】 National Key Research and Development Program of China (2016YFB0302201) National Natural Science Foundation of China (21376087) Fundamental Research Funds for the Central Universities

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(Translated by MA XQ)

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This Article

ISSN:0438-1157

CN: 11-1946/TQ

Vol 69, No. 02, Pages 555-562

February 2018

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Article Outline

Abstract

  • Introduction
  • 1 Computation model and method
  • 2 Experiment
  • 3 Results analysis and discussion
  • 4 Conclusion
  • Symbol description
  • References