ADSORPTION OF OILY SUBSTANCES OF FIBERS INVESTIGATED BY THE METHOD OFPOLARIZED ATTENUATED TOTAL-REFLECTION FI-IR SPECTRA

Polarized attenuated total reflection FT-IR spectra of fibers (silk, n ylon 6,6, cotton and polyester) adsorbed by oily substances (oleic aci d and triolein) were measured. In these spectra a new band appeared ne ar 1 700 cm-1 which is lower 5-7 cm-1 than the band assigned to the C= O stretching vibration mode of oily substances, for the cases of silk, nylon and cotton. This band may be due to oily substances adsorbed on fibers. As silk and nylon were adsorbed by oily substances, the relat ive intensity of the amide II band, which is assigned to the deformati on vibration mode of NH oriented perpendicularly to the fiber axis, de creased and the line shape of this band became broad toward the high w avenumber. On the other hand, the relative intensity of the amide II b and due to NH oriented at random increased and the peak of this band s hifted to the lower wavenumber. These facts show that C=O of oily subs tances adsorbs on NH of silk and nylon. On these spectral evidences, i t may be concluded that a mechanism for the adsorption of oily substan ces on fibers is the chemical adsorption caused by the hydrogen bondin g formed between C=O of oily substances and NH or OH of fibers.