V. Crupi et al., Inter- and intramolecular hydrogen bond in liquid polymers: a Fourier transform infrared response, MOLEC PHYS, 98(19), 2000, pp. 1589-1594
Infrared (IR) absorption measurements are employed to investigate the vibra
tional spectra of propylene glycol (PG) and its oligomers the poly( propyle
ne glycols) (PPGs) with different molecular weights (425 and 725 Da) in the
OH stretching region. The goals are to identify the intramolecular, hydrog
en bond imposed, sub-band and to connect the various sub-bands to different
intermolecular aggregates originated by the existence of the hydrogen bond
potential. The observed experimental data, compared with those of previous
IR measurements on other similar polymers, ethylene glycol (EG) and poly(
ethylene glycols) (PEGs), confirm the role played by the hydrogen bond in t
he structure of these liquids, discussed on the basis of current theories f
or associated systems.