Bian Xinchao, Chen Zhiming, Feng Lidong, Sun Bin, Xiang Sheng, Liu Yanlong, Li Gao, Chen Xuesi
Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences.
Anal Sci. 2017;33(2):235-238. doi: 10.2116/analsci.33.235.
An analytical method to determine the residual lactide in polylactide (PLA) was proposed using an internal standard method of gas chromatography (GC). PLA samples and diphenyl ether (DPE) as an internal standard were dissolved in dichloromethane, then PLA was precipitated in anhydrous alcohol. The residual lactide and DPE were extracted to alcohol for GC analysis. At room temperature, lactide could react with alcohol and change into ethyl lactoyl lactate (ELL), but the relative response factor of lactide versus DPE could be obtained through a numerical analysis method. Therefore, the residual lactide content could be quantitatively calculated in PLA. The relative standard deviation (RSD) of the measurements is not more than 7.0%, indicating that the method is suitably precise.
提出了一种采用气相色谱（GC）内标法测定聚乳酸（PLA）中残留丙交酯的分析方法。将PLA样品和作为内标的二苯醚（DPE）溶解于二氯甲烷中，然后将PLA沉淀于无水乙醇中。将残留的丙交酯和DPE萃取至乙醇中进行GC分析。在室温下，丙交酯可与乙醇反应转化为乳酸乙酯乳酸酯（ELL），但可通过数值分析方法获得丙交酯相对于DPE的相对响应因子。因此，可定量计算PLA中残留丙交酯的含量。测量的相对标准偏差（RSD）不超过7.0%，表明该方法具有适当的精密度。
