超临界流体萃取聚苯乙烯模拟样品中单体苯乙烯及定量分析

Dynamic Supercritical Fluid Extraction for Monomer Styrene from Modeling Polystyrene Sample and Quantitative Analysis Method

利用SFE＋离线毛细管气相色谱技术，对模拟PS样品中ST单体含量的定量分析方法进行了研究，结果表明：在温度为70℃、压力为18MPa的萃取条件下，优化的CO2流速为3．0～4．0标L·h^-1·g^-1。样品的实验数据与理想基质动态SFE模型吻合良好，极限提取定量聚合物产品中残单含量的方法颇为费时，而若采用外推方法，则可在较短的时间内获知聚合物样品中的残余单体含量，其相对偏差小于-3％。

A quantitative analytical method for residual monomer styrene （ST） from modeling polystyrene （PS） sample had been investigated by means of the dynamic supercritical fluid extraction and off-line capillary chromatography. Experimental results showed that the optimum flow rate of CO2 was 3.0 - 4.0 standard L·h^-1·g^-1 at 70℃ and 180 MPa. An idealized model was suggested for the analysis of the results of a dynamic supereritical fluid extraction （SFE） system form PS matrix that contains small quantities of extractable material ST, so that the extraction is not limited by solubility. The tested sample data showed good conformity to the model, in particular a linear portion was reached, which opened up the possibility of using extrapolation to obtain quantitative analytical information in shorter time than that would be required for exhaustive extraction. Relative deviation of the method was better than -3%.