物理化学学报 >> 2002, Vol. 18 >> Issue (02): 166-169.doi: 10.3866/PKU.WHXB20020215

研究简报 上一篇    下一篇

N-对甲基苯基-N′-(2-吡啶基)脲的低温热容及热分析

陆沁莹;宋永吉;孟霜鹤;邢军;谭志诚   

  1. 中国科学院大连化学物理研究所,大连 116023;北京石油化工学院化工系,北京 102600;中国石油润滑油公司大连技术中心,大连 116031
  • 收稿日期:2001-08-15 修回日期:2001-10-08 发布日期:2002-02-15
  • 通讯作者: 宋永吉 E-mail:songyj2000@sin.com

Low Temperature Heat Capacities and Thermal Analysis of N-(p-methylphenyl)-N′-(2-pyridyl)urea

Lu Qin-Ying;Song Yong-Ji;Meng Shuang-He;Xing Jun;Tan Zhi-Cheng   

  1. Thermochemistry Laboratory, Dalian Institute of Chemical Physics,Chinese Academy of Sciences, Dalian 116023;Department of Chemical Engineering,Beijing Institute of Petrochemical Technology, Beijing 102600;Dalian Technology Center,the Lubrication Company of China National Petroleum Corporation, Dalian 116031
  • Received:2001-08-15 Revised:2001-10-08 Published:2002-02-15
  • Contact: Song Yong-Ji E-mail:songyj2000@sin.com

摘要: 通过低温量热和热分析方法,测定了N-对甲基苯基-N′-(2-吡啶基)脲(以下简称NPMPN′2PU)的低温热容和热力学性质.通过对NPMPN′2PU进行低温量热,得到了NPMPN′2PU在80~370 K 温区的热容曲线,热容曲线光滑,没有任何热异常现象,由此实验热容数据计算出NPMPN′2PU在这段温区内的热力学数据.从DSC实验结果发现, NPMPN′2PU熔化峰值出现在173.86 ℃,熔化焓为204.45 kJ•mol-1.紧接熔化峰后NPMPN′2PU开始分解,分解峰只有一个,分解峰值温度为226.11 ℃.TG和DTG的实验结果表明,NPMPN′2PU失重的峰值为227.2 ℃,这些结果与DSC实验结果吻合.

关键词: N-对甲基苯基-N′-(2-吡啶基)脲(NPMPN′2PU), 低温量热,  热力学数据, 热分析

Abstract: Heat capacities of N-(p-methylphenyl)-N′-(2-pyridyl)urea were determined by low temperature adiabatic calorimetry in the temperature range of 80 to 370 K. It is found that there is no heat anomaly in this temperature region. With the experimental heat capacities thermodynamic functions were calculated. To investigate the thermal stability and decomposition characteristics of N-(p-methylphenyl)-N′-(2-pyridyl)urea, DSC and TG experiments were carried out. The results indicated that N-(p-methylphenyl)-N′-(2-pyridyl)urea started to melt at 153 ℃ and the melting peak located at 173.86 ℃. The melting enthalpy is 204.45 kJ•mol-1. The decomposition peak of N-(p-methylphenyl)-N′-(2-pyridyl)urea was found at 226.11 ℃ from DSC curve. This result is similar with that from TG and DTG experiment, in which the weight loss peak was determined as 227.2 ℃.

Key words: N-(p-methylphenyl)-N′-(2-pyridyl)urea, Adiabatic calorimetry, Thermodynamic function, Thermal analysis