Abstract
The effect of heat-treatment on diffusion of Naphthalene Fast Orange 2 GS in nylon 6 has been studied by means of microspectrophotometric (MSP) method,
While the apparent diffusion coefficient by Krämer's method _??_ exhibits a minimum at 170°C, the concentration dependence of diffusion coefficient D (c) decreases with rising temperature of dryheat-treatment.
Dry-heat-treated nylon 6 adsorbs less dyes at equilibrium in the middle region of pH than untreated one does, corresponding with the change of the amount of amino end groups, but the amount of adsorption in the higher pH increases by treatment.
In the steam-heat treatment, both the _??_ and the D (c) increase, but the concentration dependence decreases. The higher the treating temperature becomes, the more remarkable these tendencies become.
The amount of the amino end groups does not change regardless of steam-heating, A possible explanation on these results is discussed.
