差示扫描量热法测定除草剂绿麦隆的纯度

Determination of Purity of Chlorotoluron by Differential Scanning Calorimetry

研究了用差示扫描量热法（DSC）测定绿麦隆的纯度。该法测定最佳条件为升温速率0．5K·min^-1，样品量2～3mg，保护气流速20mL·min^-1。用本法测得绿麦隆原药的纯度为98．35％，相对标准偏差（RSD）为0．034％，测定结果与已知纯度相符。并将测定结果与高效液相色谱（HPLC）法进行了比较。该法具有操作简便，样品用量少，准确度和精密度均较高等优点。

Differential scanning calorimetry（DSC）was used for determination of purity of chlorotoluron. The optimal testing conditions were studied and the following conditions were selected：heating ramp of 0.5 K·min^-1 ,sample weight of 243 mg and gas flow rate of 20 mL·min^-1. The dereloped method was applied to the analysis of the purity of ehlotoroluron,and it was found to be 98.35 %,which accord with the result obtained by HPLC. Compared with HPLC, DSC method has some advantages such as less sample requined,high accuracy and short time.