液相色谱法测定SBS嵌段聚合物中结合苯乙烯含量

Determination of Bound Styrene Element in SBS Block Polymer in Liquid Chromatography

本研究系用液相色谱测定SBS中结合苯乙烯含量的分析方法。样品以四氢呋喃为流动相,经Wondasil-C18柱分离后,用紫外检测器(UVD),在260nm波长下检测出峰,记录SBS组分的峰面积。SBS中结合苯乙烯含量(S%)与SBS组分的峰面积具有线性关系,用标准曲线法进行定量。用PS与BR配制成一定比例的标准溶液,标液中PS与BR作为1个组分流出色谱柱,该组分的峰面积(A)与PS的含量(S%)成线性关系,作出A^S%标准曲线来计算SBS样品中结合苯乙烯含量。通过准确度实验,测定加标回收率在98%~104%之间;多次平行实验的相对标准偏差CV为0.67%;测定过程快速简捷;适应SBS、SSBR等苯乙烯与丁二烯共聚物中结合苯乙烯含量的测定。

Determination of bound styrene element in SBS in liquid chromatography is analyzed in the paper. The tetrahydrofuran as sample with mobile phase is separated by Wondasil-C18 column and is detected with an ultraviolet detector under the wave length of 260 nm, and the peak area of SBS is recorded. The styrene content（S%） of SBS shows a linear relationship with the peak area of SBS which could be analyzed quantitatively with standard curve. The standard solution was prepared by mixing the standard sample of polystyrene（PS） and polybutadiene（BR） oligomer at a certain proportion（S/B）. The polymer component of PS and BR is flowed out of the chromatographic column as a mixture component, and its peak area（A） also showed a linear relationship with the element of PS（S%） that could be calculated according to the standard curve of A-S%. The recovery rate of 98%-104% is measured by accuracy experiment. The relative standard deviation CV of parallel experiments is 0.67%. This determination method is rapid and convenient, also is suitable for the determination of bound styrene content in the copolymer of styrene and butadiene like SBS and SSBR.