甲基苯基碳酸酯标准品的制备及其定量分析

利用甲基苯基碳酸酯(MPC)歧化反应的可逆性及逆反应在热力学上有利进行的特点,提出了以碳酸二甲酯 (DMC)和碳酸二苯酯 (DPC)为原料,在TiO2/SiO2催化下合成DMC与苯酚酯交换反应的中间产物MPC的新方法。反应产物经减压精馏、碱洗、水洗、干燥等精制处理，得到了纯度较高的MPC标准品。采用气相色谱-质谱法对所制备的MPC样品进行定性分析，结果表明其中还含有少量的苯酚和DPC杂质。卡尔·费休水分测定结果表明,MPC样品中的含水量为0.26%(质量分数)。使用常规气相色谱仪，采用OV-101毛细管色谱柱,以苯甲酸乙酯为内标物,对自制的MPC标准品中的微量苯酚和DPC进行定量分析,苯酚和DPC的含量分别为2.04%和1.59%（均为质量分数）。根据杂质分析结果可知自制的MPC标准品的纯度为96.11%。以此作为标准品,解决了对DMC与苯酚酯交换反应的中间产物MPC的准确定量问题。

Preparation and Quantitative Analysis of Methyl Phenyl Carbonate Standard Sample

The preparation and quantitative analytical method for high-purity methyl phenyl carbonate(MPC) was developed.Dimethyl carbonate(DMC) and diphenyl carbonate(DPC) were firstly used as reactants to synthesize MPC catalyzed by TiO_2/SiO_2 because the disproportionation of MPC is reversible and the reverse reaction is thermodynamically favorable.The high-purity MPC standard sample was obtained by reduced pressure distillation and the removal of minor phenol with dilute sodium hydroxide solution.The qualitative analysis by gas chromatography-mass spectrometry(GC-MS) showed there were minor phenol and diphenyl carbonate in the MPC sample.The mass percent concentration of water in the MPC sample was (0.26%),which was determined by Karl Fischer titration.A gas chromatographic method with an OV-101 capillary column was established for quantifying the minor phenol and DPC in the MPC sample.The quantitative results showed the mass concentrations of phenol and DPC were(2.04%) and(1.59%,) respectively.The difficulty to analyze MPC,the intermediate product of the transesterification of DMC and phenol,was solved with the self-made MPC standard sample.