Vibrational analysis of molten poly(ethylene glycol)

The infrared absorption of poly(ethylene glycol) was measured in the molten state. Characteristic bands of the molten state were identified. Normal vibrations and frequency distributions were treated for various conformation models with CH 2 CH 2 O repeat units. The infrared absorption peaks of the molten state closely correspond to the frequency distribution peaks of the TGT conformation with gauche OCH 2 CH 2 O groups, although infrared bands due to trans OCH 2 CH 2 O groups are also observed. Vibrational assignments of the infrared bands and Raman lines were made on the basis of potential energy distributions.