抄録
While heat setting of acrylic fiber has been studied extensively with regard to the relation between the heating condition and the changes of fine structure and dyeing property.
In this paper, acrylic fiber heated in hot air was cooled under various conditions and the effect was studied on the crease recovery, the flexural rigidity, the dyeing property and the density of acrylic fiber.
The results obtained were as follows:
1) Acrylic fibers, treated with hot air at 120, 140, 160 and 180°C, were cooled gradually or rapidly in water down to 100-0°C. Crease recovery angle was greatly affected by the cooling temperature and the method. The higher the cooling temperature, the greater the crease recovery angle. Rapid cooling decreased the crease recovery angle considerably. Therefore, it is desirable to cool the fiber gradually at the neighborhood of glass transition temperature of acrylic fiber.
2) The cooling condition was also influencial to the handling of acrylic fiber. Flexural rigidity as a measure of handling was measured by cantilever method. Soft handling was obtained by the gradual cooling.
3) The density of fiber was determined by means of a density gradient tube. The density decreased by gradual cooling, while increased by rapid cooling.
4) In spite of increase of crystallinity by rapid cooling, the dyeing velocity and the sorption at dyeing equilibrium increased, possibly due to the increase of structural disorder in amorphous region.
