Abstract
In the previous reports, it has been shown that the degree of crystallinity of nylon 6 is increased by heat treatments and that the diffusion rate of dyes is increased by steam-setting, while it is decreased by dry-heat-setting. These phenomena have been explained in terms of the packing structure of amorphous parts of heat-treated polymers. In this report, the results supporting this explanation are obtained from a quantitative analysis of infrared spectra. Heat-treated nylon 6 films (their thickness are 10-20μ) were reacted with D20 at 60°C for 100 hrs. in vapour phase. Integral intensities of N-D stretching vibration band on the spectra were calculated as follows.
1/(1-α) l·∫logI0/Idr=K′·C
where l0 and I are the intensity of the incident and transmitted light respectively, l, the thickness, and a, the degree of crystallinity. Here, K′·C represents the number of unbonded N-H groups in the amorphous part. The result shows that K′·C increase by steam-setting while it decreses by dry-heat-setting. Thus the said structural changes in the amorphous part. are recognized.
