A Yew Technique for Infrared Spectroscopy using Polyethylene Film Cell

Polyethylene Film을 利用한 赤外線分光分析用 Cell

Authors propose a new technique using polyethylene film instead of sodium chloride window as a cell material. Nujol mulls, liquids and aqueous solutions are sandwitched between two pieces of polyethylene film which are held between cardboards. Ordinary lead or stainless steel spacers could be used if exact cell thickness is desired. A more elaborate cell can be assembled by injecting samples between two pieces of polyethylene film which are placed between sodium chloride windows of ordinary demountable liquid cell. The absorption bands due to polyethylene and Nujol are compensated by placing the polyethylene film of suitable thickness in the reference beam. The absorption bands due to solvents such as water can also be compensated by the polyethylene film cell sandwitched solvent of suitable thickness in the reference beam. This method would be a simple new technique. Especially this technique may offer a new helpful way for the investigation of the state of substances in aqueous system. Using this technique, authors have observed the appearance of an absorption bands at 3.2 micron, in the spectrum of phenol in aqueous solution, that is absent in the spectrum of phenol in benzene solution. The same absorption band also has been observed in the spectra of aqueous formaldehyde solution and aqueous polyvinyl alcohol solution, where the absorption bands due to polyethylene and water are compensated. Although it may be regarded that this absorption band is related to the intermolecular interaction between water and the solute having OH group, that is hydrogen bonding. The exact assignment of this absorption band is out of this work.