无水醋酸钠结构及热稳定性

Structure and thermal stability study of CH3COONa

采用中红外(MIR)光谱开展了醋酸钠的分子结构研究。发现醋酸钠分子的红外吸收模式主要包括:CH3不对称伸缩振动模式(νasCH3-醋酸钠)、CH3对称伸缩振动模式(νsCH3-醋酸钠)、COO-不对称伸缩振动模式(νasCOO--醋酸钠)、COO-对称伸缩振动模式(νsCOO--醋酸钠)和CH3摇摆振动模式(ρCH3-醋酸钠)等。采用变温中红外(TD-MIR)光谱进一步开展了温度变化对于醋酸钠结构的影响。研究发现:在303~423 K的温度范围内,随着测定温度的升高,醋酸钠主要官能团(νasCH3-醋酸钠、νsCH3-醋酸钠、νasCOO--醋酸钠、νsCOO--醋酸钠和ρCH3-醋酸钠)对应的红外吸收频率和强度均没有明显的改变,从而进一步证明醋酸钠具有良好的热稳定性。

The CH3COONa organic molecular structure were characterized by the infrared(MIR)spectroscopy.There were CH3 asymmetric stretch vibration mode(νasCH3-CH3COONa),CH3 symmetrical stretch vibration mode(νsCH3-CH3COONa),COO-asymmetric stretch vibration mode(νasCOO--CH3COONa),COO-symmetrical stretch vibration mode(νsCOO--CH3COONa)and CH3 rocking vibration mode(ρCH3-CH3COONa).The temperatureeffect on CH3COONa structure by temperature-dependent infrared(TD-MIR)spectroscopy were studied also in the temperature range 303 K^423 K.With the increase of the temperature,the corresponding frequencyand intensity of CH3COONa(νasCH3-CH3COONa,νsCH3-CH3COONa,νasCOO--CH3COONa,νsCOO--CH3COONa andρCH3-CH3COONa)did not changed obviously and the thermal stability of CH3COONa was better.