Korea-Australia Rheology Journal

The Korean Society of Rheology (한국유변학회)
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High-pressure rheology of polymer melts containing supercritical carbon dioxide

  • Lee Sang-Myung (Applied Rheology Center Dept. of Chemical Engineering, Sogang University) ;
  • Han Jae-Ro (Applied Rheology Center Dept. of Chemical Engineering, Sogang University) ;
  • Kim Kyung-Yl (Applied Rheology Center Dept. of Chemical Engineering, Sogang University) ;
  • Ahn Young-Joon (Applied Rheology Center Dept. of Chemical Engineering, Sogang University) ;
  • Lee Jae-Wook (Applied Rheology Center Dept. of Chemical Engineering, Sogang University)
  • Published : 2006.06.01
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Abstract

Supercritical carbon dioxide ($scCO_2$) has advantages of being incorporated in polymer with high solubility and of being recovered easily by depressurizing. $scCO_2$ reduces the viscosity of polymer melt and it is expected to be use as a plasticizing agent. In this work, we studied on the effect of $scCO_2$ on the rheological properties of polymer melts during extrusion process. Slit die attached to twin screw extruder was used to measure the viscosity of polymer melts plasticized by supercritical $CO_2$. A gas injection system was devised to accurately meter the supercritical $CO_2$ into the extruder barrel. Measurements of pressure drop within the die, confirmed the presence of a one phase mixture and a fully developed flow during the measurements. The viscosity measurement of polypropylene was performed at experimental conditions of various temperatures, pressures and $CO_2$ concentrations. We observed that melt viscosity of polymer was dramatically reduced by $CO_2$ addition.

Keywords

References

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