Effect of Heat-Setting Temperature on the Hydrazine Treatment of Poly (ethylene Terephthalate) Partially Oriented Yarn

Abstract

Poly (ethylene terephthalate) partially oriented yarn (PET POY) was heat set at 100 to 220°c in a fixed state and then treated with hydrazine. Although crystallinity of the heat-set PET POY increased with increased heat-setting temperature, weight loss from the hydrazine treatment initially decreased at a temperature up to 120°c and subsequently increased above 120°c. The hydrazinolyzed POY fiber is dyeable with acid dyes because of the hydrazide groups incorporated by hydrazinolysis. Nitrogen content and dye exhaustion with CI acid orange 7 showed trends similar to the weight loss of the hydrazinolyzed POY fibers. On the other hand, the dyeability of the hydrazinolyzed POY fibers with CI disperse violet 1 was lower than that of the untreated fibers. Many cracks appeared on the surface of the hydrazinolyzed fibers, and they were smallest on the fibers that were heat set at 120°c.

A study of one‐bath alkali–amine hydrolysis and silk‐fibroin finishing of polyester microfiber crepe fabric

“…Alkaline hydrolysis9, 10 of PET fiber is a highly developed silk‐like modification technique. In theory, PET undergoes a nucleophilic substitution and is hydrolyzed by a NaOH solution.…”

Surface hydrolysis of filaments based on poly(trimethylene terephthalate) spun at high spinning speeds

“…As the outer layer of non-heat-set PET fiber is hydrolyzed, the fiber surface becomes rougher and relatively small irregular pits are observed. 12,18 Because heat setting increases the crystallinity, it may also produce more open fiber structure 12,21 ; consequently, one could expect that the surface of our heat-set and hydrolyzed PTT filaments should be more porous.…”

“…11 Furthermore, some researchers studied the effect of heat-setting temperature on the hydrazine treatment of PET. 12 Although the alkaline hydrolysis of PET fibers usually leads to a slightly pitted surface, we thought that varying the fiber structure could affect the rate of hydrolysis and perhaps would result in the development of a more porous and hydrophilic fiber surface. Poly(trimethylene terephthalate) (PTT) was then chosen for the investigation.…”

Pretreatment of Proteinic and Synthetic Fibres Prior to Dyeing

“…Heat setting of polyester fibers is processed to make a change in the fine structure and consequently dyeability and chemical reactivity (39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49) . The effect of heat setting temperature on the hydrazinolysis of polyester fibers was studied.…”