采用DSC测量PEG_(10000)熔融焓变测定条件的研究

Study on Test Conditions of the Melting Enthalpy about PEG_(10000) Measured by Using DSC

采用不同的升温速率和样品用量,分别测得差示扫描量热法(DSC)特征曲线和PEG10000的熔融焓变。结果表明:用DSC测试PEG10000的熔融峰温度(Tp)和熔化焓(△H)时,尽可能保证外界环境的一致,并使仪器降至原来的温度,消除热历史的影响。在仪器允许的范围内,低升温速率及减少样品用量可使熔融峰更尖锐、明显,并使用保护气体以防止PEG的氧化。

The differential scanning calorimetry （DSC） characteristic curve and melting enthalpy of PEG10000 were measured with different heating rates and content of PEG10000. The results showed that the external environment as far as possible to ensure consistent and the equipment must be cooled to original temperature in order to eliminate thermal history when melting temperature peak （Tp） and melting enthalpy （AH） of PEG10000 were tested by using DSC. The melting peak will be even more accurately and clearly in the low heating rate and small amount of the sample within the permissible range of the apparatus, and the protective gas must be used in case of the oxidation of PEG.