乙二醇硬脂酸酯合成实验改进研究

Improved study on the synthesis experiment of ethylene glycol stearate

乙二醇硬脂酸酯是一类珠光剂,主要应用于日用化学品领域。以乙二醇和硬脂酸为起始原料,对甲苯磺酸为催化剂,合成乙二醇硬脂酸酯。采用中红外(MIR)光谱开展了乙二醇硬脂酸酯分子的结构表征。试验发现,乙二醇硬脂酸酯的红外吸收模式主要包括:CH3不对称伸缩振动模式(ν(_(asCH_(3-乙二醇硬脂酸酯))))、CH2不对称伸缩振动模式(ν_(asCH_(2-乙二醇硬脂酸酯)))、CH_(3)对称伸缩振动模式(ν_(sCH3-乙二醇硬脂酸酯))、CH_(2)对称伸缩振动模式(v_(sCH_(2)-乙二醇硬脂酸酯))、C=O伸缩振动模式(v(C=O-乙二醇硬脂酸酯))、CH_(2)变角振动模式(δ(CH_(2-乙二醇硬脂酸酯)))、CH_(2)面外摇摆振动模式(ω_(CH_(2)-乙二醇硬脂酸酯))和CH_(2)面内摇摆振动模式(ρ_(CH_(2-)乙二醇硬脂酸酯))。当乙二醇与硬脂酸按近似等摩尔投料时,产品以单酯(乙二醇单硬脂酸酯)为主,并进一步探讨研究其反应机理。

Ethylene glycol stearate is a type of pearlescent agent mainly used in the field of daily chemicals.Ethylene glycol stearate was synthesized using ethylene glycol and stearic acid as starting materials and p-toluenesulfonic acid as catalyst.The structural characterization of ethylene glycol stearate molecules was carried out using middle infrared(MIR)spectroscopy.The experiment found that the infrared absorption mode of ethylene glycol stearate mainly includes:CH_(3)asymmetric stretching vibration mode(ν_(asCH_(3-ethylene glycdl strarate))),CH_(2)asymmetric stretching vibration mode(ν_(asCH_(2-ethylene glycdl strarate))),CH_(3)symmetric stretching vibration mode(ν_(sCH_(3-ethylene glycdl strarate))),CH_(2)symmetric stretching vibration mode(ν_(asCH_(2-ethylene glycdl strarate))),C=O stretching vibration mode(_(asCH_(3-ethylene glycdl strarate))ν),CH_(2)bending vibration mode(δ_(CH_(2--ethylene glycdl strarate))),CH_(2)out of plane wagging vibration mode(ω_(CH_(2--ethylene glycdl strarate)))and CH_(2)in-plane rocking vibration mode(ρ_(CH_(2--ethylene glycdl strarate))).When ethylene glycol and stearic acid were fed in approximately equal moles,the product mainly consists of monoesters(ethylene glycol monostearate),and the reaction mechanism was further explored and studied.