Abstract
To reveal the antifreeze protection mechanism of an aqueous solution of ethylene glycol (EG) at a molecular level, concentration-dependent infrared spectra are analyzed with an aid of chemometrics. The principal component analysis (PCA) of the spectra reveals that the spectral variation is explained by the quantity changes not only of ‘bulky water’ and the ‘bulky EG,’ but also of a ‘water/EG complex.’ After a spectral decomposition using the alternative least squares (ALS) analysis, the spectrum of the complex reveals that the EG molecule keeps the gauche conformation, and the terminal hydroxyl groups are hydrogen bonded by water molecules, which is a key to understand the antifreeze effect. In addition, the complex is found to comprises an EG molecule with four water molecules. Since the quantity of the complex attains the maximum at an EG concentration of 60wt%, at which the freezing point becomes lowest, the complex is concluded to be a key hydrated species for the antifreeze effect. The generation process of the water/EG complex is also studied by using the time-resolved IR spectroscopy, which consistently confirms the spectral discussion made above.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
