Establishment And Application Of Infrared Spectral Database Of Surfactant Products

Surfactants are an important textile industry chemical additives, which can improve product quality, product performance and give products a new value. According to the chemical nature of the surfactants, surfactants can be classified as anionic surfactants, cationic surfactants, nonionic surfactants and zwitterionic surfactants. There are many types of surfactants which used in the textile industry are up to 3,000 species. Different surfactants will give the product different performances. Thus the qualitative analysis of the surfactant in the textile industry is an important research topic. Infrared spectrometry has many advantages, such as simple sample preparation, fast test speed and non-pollution. This paper tested the common surfactant products by Nicolet IRAffinity-1 Infrared Spectrometer. The main contents are as follows:1.Collecting spectral information of commonly used surfactants. Selecting the highest spectral transmittance between 100% to 95%, the lowest spectral transmittance between 20% to 10% and the peak transmittance spectra do not overlap as the standard ATR spectra. Establishing IR database of surfactant products. The characteristic absorption peak of AEO are 3465cm-1 of O-H stretching vibration,2956cm-1 and 2871cm-1 of methyl stretching vibration,2924cm-1 and 2855cm-1 of methyl stretching vibration,1458cm-1,1375cm-1, 1350cm-1,1300cm-1,1250cm-1,881cm-1,842cm-1 and 723cm-1[(CH2)n, n≥4] of methyl and methyl,1107cm-1,1041cm-1 and 947cm-1 of ether bond. The characteristic absorption peak of SAS60 are 3450cm-1,1645cm-1,2954cm-1,2922cm-1,2854cm-1,1465cm-1,1377cm-1, 721cm-1,1174cm-1,1052cm-1 of O-H, C-H, S=O vibration. The characteristic absorption peak of sulfonated bodies of ATA90 are 3475cm-1,3214cm-1,3100～3010cm-1,761cm-1, 701cm-1,1250cm-1,1027cm-1,1600cm-1,1492cm-1,1451cm-1,2870cm-1,1350cm-1, 1249cm-1 of N-H, C-H,=C-H, S=O vibration.2. Aqueous of common surfactant products were prepared, then collected infrared spectrum of these solutions. We will explore the feasibility of using infrared subtractive spectroscopy technique on aqueous of common surfactant products. The study found that when the content of aqueous of one surfactant is below 5%,absorption peaks of water covered absorption peaks of surfactant. When using infrared subtractive spectroscopy technique to deal with the spectrum, we can not retrieve the target spectra. When the content of surfactants exceeded 15%, we can retrieve the target spectrum by retrieve the target spectra.3. In order to improve product performances, surfactants are often mixed to use. The mixed aqueous of surfactants were studied. Aqueous solution of two different types of surfactants were prepared, then collected infrared spectrum of these solutions. After subtracting peaks of water by infrared subtractive spectroscopy technique, we retrieve the obtained spectrum and determined one component of the solution, and subtract the infrared spectra of the component. Then retrieve the obtained spectrum again, determined the other component. And we will explore the feasibility by using infrared subtractive spectroscopy technique on aqueous of mixed surfactant products. We found that when the content of one component exceeded 5%, and the mixing ratio of the two components is between 1/3 to 3, the subtraction spectra is better. When the content of the two components are equal, the subtraction spectra is best. If exceed this range, the resulting spectrum will much different from the standard spectrum.