Thermal stability and yellowing of polyamide finished with a compound anti-thermal-yellowing agent

Abstract

In order to enhance the thermal stability and reduce the thermal yellowing of polyamide fabrics, a kind of compound anti-thermal-yellowing agent made up by urea, sodium hypophosphite, and adipic dihydrazide was finished to polyamide in this study. The structure change and the thermal stability of the polyamide were investigated by the analysis of TG-DSC, TG-FTIR curves, viscosity-average molecular weight, and end carboxyl group content of polyamide fibers. The anti-yellowing effect was evaluated by whiteness and yellowing index values. The results showed that the compound anti-thermal-yellowing agent could enhance the decomposition temperature and hinder the thermal-oxidative degradation of polyamide. Besides, the whiteness values of the fabrics treated by the anti-thermal-yellowing agent were distinctly higher than that of untreated fabrics and fabrics treated by Umidol UWP but the yellowing index values were lower, which supported that the thermal stability of the polyamide treated by the anti-thermal-yellowing agent became better.

Keywords:

• polyamides
• thermal stability
• degradation
• anti-thermal-yellowing
• whiteness