Influence of Spinneret Dimensions on Modacrylic Fiber Properties

Abstract

Optimum L/D values (capillary length to diameter ratio) of a spinneret for mod acrylic fibers with various deniers are obtained in this study. When the denier of fibers with 33% chlorine content is smaller than 5, the smaller the denier of the fiber, the larger the diameter of the spinneret capillaries must be to obtain good properties. When the denier of fibers with 33% chlorine content is larger than 5, the larger the denier, the larger the diameter of the capillaries must be. Thus, there is a critical point for L/D values at about 5 denier. When the chlorine content of the fibers is higher, denier has a large effect on the limiting oxygen index (LOI) value. If the chlorine content is about 8%, the LOI value for modacrylic fibers is almost not affected by denier.