Two-dimensional (2D) correlation analysis was applied to FTIR variable-temperature spectra of polyamide 6 to investigate the structure response of the hydrogen bonds and the hydrocarbon chains during the heating process ((25～200)℃). It is shown that the NH-related absorption bands and the antisymmetric stretching vibrations of the methylene groups are very sensitive to the temperature-induced structural changes of the polyamide 6 sample. Thus, the sequence of the loosening of amide hydrogen bonds and the conformational changes of the methylene groups can be inferred by the two-dimensional correlation analysis of FTIR variable-temperature spectra.

Key words: polyamide 6, amide hydrogen2bonding, two-dimensional correlation analysis, variable-temperature FTIR