Dynamic Supercritical Fluid Devolatilization of Polymers  

作　　者：叶树明 蒋凯 蒋春跃 潘勤敏 

机构地区：[1]College of Biomedical Engineering and Instrument Science,Zhejiang University,Hangzhou 310027,China [2]College of Chemical Engineering and Materials Science,Zhejiang University of Technology,Hangzhou 310014,China [3]Department of Chemical Engineering,University of Waterloo,Waterloo,Ontario,Canada N2L 3G1

出　　处：《Chinese Journal of Chemical Engineering》2005年第6期732-735,共4页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No. 20576123).

摘　　要：A number of studies have been reported on the applications of supercritical fluids to polymeric processes. The presence of volatiles can affect the end-use properties of polymer materials. Therefore, these volatiles must be reduced to a level below the maximum permissible limit. Conventional heat-relevant techniques for polymer devolatilization sometimes have limited effectiveness. Devolatilization with supercritical fluids, however, can enhance removal of volatiles from polymers. A model for diffusion-limited extraction is used to characterize dynamic supercritical fluid devolatilization of spherical polymer particles. The rate of supercritical fluid devolailization for styrene/polystyrene system is measured at 343 K and 18 MPa and at CO2 flow rate of 1.93, 3.27 and 5.62 L·min^-1, respectively. The model analysis, which is consistent with experimental results, indicates that the supercritical fluid devolatilization is not solubility-limited but diffusion-limited when CO2 flow rate is above 4.00 L·min^-1.A number of studies have been reported on the applications of supercritical fluids to polymeric processes. The presence of volatiles can affect the end-use properties of polymer materials. Therefore, these volatiles must be reduced to a level below the maximum permissible limit. Conventional heat-relevant techniques for polymer devolatilization sometimes have limited effectiveness. Devolatilization with supercritical fluids, however, can enhance removal of volatiies from polymers. A model for diffusion-limited extraction is used to characterize dynamic supercritical fluid devolatilization of spherical polymer particles. The rate of supercritical fluid devolailization for styrene/polystyrene system is measured at 343 K and 18 MPa and at CO2 flow rate of 1.93, 3.27 and 5.62L·min-1, respectively. The model analysis, which is consistent with experimental results, indicates that the supercritical fluid devolatilization is not solubility-limited but diffusion-limited when CO2 flow rate is above 4.

关 键 词：supercritical fluid devolatilization supercritical CO2 diffusion coefficient STYRENE POLYSTYRENE 

分 类 号：O631.3[理学—高分子化学]