INTERACTION BETWEEN MODELS OF POLYESTER AND DISPERSE DYES

Infrared absorption spectra of model compound, dimethyl terephthalate [1a], of poly (ethylene terephthalate) (PET) and methyl p-methoxybenzoate [2a], of poly(ether ester) (PEET), in the presence of disperse dyes was investigated in tetrachloroethane solution. Their hydrogen-bonding interaction was disscussed. Disperse dye [3], 4-hydroxyazobenzene, in terachloroethane exhibited an absorption band with a peak at 3575 cm-1 ascribed to hydroxyl group, and disperse dye [4], 4-anilino-3-nitro-N-phenylbenzenesulfonamide, at 3343 cm-1 to imino group. The addition of 1a and 2a to the above disperse dye solution resulted in a decrease of the absorbance at 3575 cm-1 and 3343 cm-1, and other new absorption bands appeared at lower frequency. Both results are attributed to hydrogen bonding. The same results were also observed for the model compounds of PET containing two p-phenylene groups [1 b] and the three groups [1 c], and the model compounds of PEET containing the two groups [2 b] and the three groups [2 c].