温度对N-月桂酰肌氨酸与三乙醇胺反应产物结构及性能的影响

Effect of temperature on structure and properties of the reaction product of N-lauroyl sarcosine and triethanolamine

针对N-月桂酰肌氨酸与三乙醇胺的反应过程中产物结构不明确、性能不稳定等问题,考察了反应温度对N-月桂酰肌氨酸与三乙醇胺反应产物结构的影响,通过红外光谱、核磁共振氢谱及质谱对其结构进行了分析确认。结果表明:低温(75℃)条件下,更容易获得阴离子型表面活性剂(产物A),高温(130℃)条件下,更容易获得非离子型表面活性剂(产物B)。对两种产物的泡沫性能及抗硬水能力进行了对比,结果显示,当质量分数小于0.8%时,产物A的表面张力大于产物B的表面张力,且在质量分数为0.15%时,表面张力均达到最小,此时产物A与产物B的泡沫半衰期分别为22.56和28.26min。当质量分数为1.0%时,产物B的抗硬水能力比产物A的提升了30.5%,更有利于乳液稳定。

In the reaction process of N-lauroyl sarcosine and triethanolamine, the structure of the product is not clear and the performances are unstable. Aiming at these problems, the effects of reaction temperature on the structure of N-lauroyl sarcosine triethanolamine reactants were studied. The structure was confirmed by Fourier transform infrared spectroscopy, HNMR and mass spectrometry. The results showed that the anionic surfactant(product A) was more easily obtained at low temperature(75 ℃), and the nonionic surfactant(product B) was more easily obtained at high temperature(130 ℃). The foam properties and hard water resistance of the two products were compared. It was found that when the mass fraction was less than 0.8%, the surface tension of product A was greater than that of product B. While the mass fraction was 0.15%, the surface tension of product A and product B was the smallest, and their corresponding foam half-lives were 22.56 min and 28.26 min, respectively. When the mass fraction was 1.0%, the ability of product B to resist hard water was 30.5% higher than that of product A, which was more conducive to the stability of emulsion.