The modifying effect of weak aqueous solutions of ammonia on poly(ethylene terephthalate) materials

The effect of water and aqueous solutions of ammonia of 0.02–0.04 M concentration on poly(ethylene terephthalate) and fleecy knit fabric was comparatively investigated at high temperatures. It was found that migration of oligomers to the surface of the polymer, partial hydrolysis of cyclic oligomers to the linear form, and total hydrolysis to TPA are possible under the effect of water, but water affects the knit much less than the film. The presence of ammonia intensifies the processes that can take place with oligomers of PET at high temperatures to a significant degree. The concentration of ammonia in the system determines which of these processes will predominate. It was found that a 0.015–0.03 M concentration of ammonia is optimum for refining polyester fibre materials. __________ Translated from Khimicheskie Volokna, No. 6, pp. 15–18, November–December, 2006.