2,3,4-三氯苯甲醚标准物质研制与定值

研制了2,3,4-三氯苯甲醚标准物质,介绍了其制备与定值方法。将制备的2,3,4-三氯苯甲醚标准物质分装成500瓶样品,随机抽取其中11瓶做均匀性检验,经F检验和t检验,结果表明在95%置信范围内样品均匀性良好。按短期与长期稳定性分别进行稳定性检验,结果表明在常温20℃下,2,3,4-三氯苯甲醚的稳定期不少于12月。采用液相色谱法和差示扫描量热法2种不同原理的方法对2,3,4-三氯苯甲醚标准物质纯度定值及不确定度评定,并采用液相色谱标准添加的方法确认了2,3,4-三氯苯甲醚标准物质中的主要杂质2,3,6-三氯苯甲醚。定值结果为99.56%± 0.40%（k=2）。

Development and Certification of 2.3.4-trichloroanisoles Certified Reference Material

A method for development and certification of certified reference material of 2,3,4-trichloroanisoles is presented.According to analysis procedure of homogeneity, 11 bottles of sample are taken from 500 bottles at random, and the result is validated by F-test and T-test statistical methods. The stability inspection is carried on short-term(1 month) and long-term(12 months), the result indicated that the period for 2,3,4-trichloroanisoles of storage is 12 months at 20℃.The purity of 2,3,4-trichloroanisoles are determined by two methods of different principles, which are high performance liquid chromatography method and differential scanning calorimetry method.The qualitative analysis of main impurity is determined with standard addition by liquid chromatography with photo-diode array and the impurity is 2,3,6-trichloroanisoles; The content of water in 2,3,4-trichloroanisoles is measured by Karl-Fischer titrator with drying oven. The uncertainty of HPLC and DSC methods are respectively evaluated. The certified result is 99.56% and expanded uncertainty is 0.40%（k=2）.