Sj. Law et Sk. Mukhopadhyay, HOT-STRETCH-INDUCED ORIENTATION AND COLLAPSE OF WET-SPUN ACRYLIC-FIBER STRUCTURE AND EFFECTS ON GEL-DYEING, J TEXTILE I, 89(2), 1998, pp. 182-197
The effect of stretch-induced orientation and structural collapse of a
s-formed wet-spun acrylic fibre on subsequent gel-dyeing characteristi
cs is assessed. The gel-dye rate is shown to increase with increasing
stretch ratio. This is demonstrated to be a consequence of the reduced
time spent in the steam-stretch tunnel, leading to less reduction of
porosity at higher stretch ratios, rather than the polymer orientation
al effects observed. The link between steam-tunnel residence time and
structural collapse is extended to examine the dynamics of stretching
and introduces the notion of a stretch point, that distance travelled
by a fibre bundle in the tunnel at which stretching takes place. This
dictates the residence time in the tunnel and hence the level of colla
pse. The mechanism is offered as a possible cause of fibre-shade varia
tion.