DRAWING OF POLYETHYLENE OXIDE FIBER

Abstract

In order to improve the tensile properties of polyethylene oxide (PEO) fiber, two different drawing methods were employed; one was a dry process which was carried out in an air oven, and another a wet process using liquid paraffin as a medium which was a non-solvent of PEO.In the hot air, PEO could be drawn more than in the liquid paraffine as shown in Figure 1.The change in the molecular orientation in the fibers was examined by means of X-ray analizer and a polarizing microscope. In the case of dry process, the degree of orientation tended to decrease in the earlier stage of drawing and showed a minimum at draw ratio of 1.5, On the other hand, in the wet drawing, it was monotonically decreased with increasing draw ratio. Even in this case, however, the increase of the drawing rate resulted the relation of draw ratio to birefringence similar to that in the hot air.From these results, it is evident that the orientation of drawn fiber is governed not only by the draw ratio but also by the heat capacity and the heat conductivity of a drawing medium.Regardness of the anomolous change in the optical anisotropy, the drawing method does not affect the tensile properties of the drawn fibers, and hence, the tenacity and the residual elongation of PEO fibers are determined only by its molecular weight and the draw ratio.