间苯二酚二羟乙基醚纯度的差示扫描量热法测定

Purity Determination of 1,3-Bis(2-hydroxyethoxy)benzene by Differential Scanning Calorimetry

介绍用差示扫描量热法(DSC)测定结晶物质纯度的原理和实验过程,讨论了Van'tHoff方程和DSC法对间苯二酚二羟乙基醚(HER)样品的适用性,用DSC法测定了不同厂家、不同批次的几种HER产品的纯度。当样品纯度(摩尔分数)高于98.0%时,平行测定结果之差≤0.1%(绝对差),测定结果与高效液相色谱法(HPLC)一致。在测定纯度的同时,测得HER的理论熔点(无限纯样品的熔点)为89.48±0.05℃,熔融热为39.4±0.7J/mol。

The principle and experimental process for determining the purity of crystal substance by differential scanning calorimetry （DSC） are described. The applicability of Van＇t Hoffequation and DSC method to 1,3-bis（2-hydroxyethoxy）benzene（HER） samples is discussed. The purities of several HER products of different batches from different manufacturers were determined by DSC method. The deviations（absolute） between two parallel experimental results are not more than 0.1% if the purities（molar fraction） of samples are more than 98.0%. The determination results of import sample accorded with those by HPLC method. It was determined that the theoretical melting point of HER （infinite pure sample） is 89.48 ± 0.05℃ and the fusion heat of HER is 39.4 ±0.7J/mol along with the purity determination.