文献类型：期刊文献

英文题名：Study of the Anomalous Sorption Behavior of CO2 into Poly(methyl methacrylate) Films in the Vicinity of the Critical Pressure and Temperature Using a Quartz Crystal Microbalance (QCM)

作者：Li, Xue-Kun[1];Cao, Gui-Ping[1];Chen, Li-Hua[1];Zhang, Ren-Han[1];Liu, Hong-Lai[1];Shi, Yun-Hai[1]

机构：[1]E China Univ Sci & Technol, UNILAB, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：29

期号：46

起止页码：14089

外文期刊名：LANGMUIR

收录：;EI(收录号：20135017064127);WOS:【SCI-EXPANDED(收录号:WOS:000330144100013)】；

基金：This work was supported by the National Natural Science Foundation of China (NSFC), Grants 20676031 and 20876051. We are also grateful to professor You-Ting Wu from the School of Chemistry and Chemical Engineering of Nanjing University for helpful comments and suggestions.

语种：英文

外文关键词：Semiconducting films - Solubility - Polymer films - Quartz - Sorption - Temperature - Thin films - Esters - Quartz crystal microbalances

摘要：The anomalous solubility maximum of CO2 in polymer thin films in the vicinity of the critical temperature and pressure has not yet been clearly understood when the quartz crystal microbalance (QCM) technique has been used to determine the micromass change. In this study, the adsorption of CO2 on the surface of bare polished and unpolished crystals at different pressures and temperatures was investigated using the QCM technique to illustrate why a plot of the true frequency shift as a function of temperature and pressure can intuitively exhibit the adsorption behavior of CO2 on bare crystals. The sorption of CO2 into a PMMA film at different temperatures, pressures, and PMMA film thicknesses was also investigated. An accurate solubility for CO2 in the PMMA film could be obtained by an improved data correction method from the linear relation between the true frequency shift and the polymer film mass, and the anomalous solubility maximum could be corrected by this method. The mechanism of nonabsorbed CO2 transitorily staying in the interspace between the PMMA film and the crystal surface can be explained by the morphology change of the PMMA film. The assumption of "passerby CO2" was satisfactorily confirmed to explain the anomalous sorption behavior of CO2 into PMMA films in the vicinity of the CO2 critical temperature and pressure, and this assumption could be valid for other CO2-polymer thin film systems.