Abstract: An acrylic fiber tow which includes 1) monocomponent filaments of each of two acrylonitrile polymers differing in hydrophilic properties, 2) bicomponent filaments of both of said polymers having one interface between polymers components and 3) bicomponent filaments of both of said polymers having more than one interface between polymer components. This fiber, however, in spite of its composition of numerous filaments of differing structure provides a tow bundle having a desirable level of reversible crimp measured in a manner specific to the type of crimp designated.

Abstract: An acrylic fiber tow is disclosed which comprises 1) monocomponent filaments of each of two acrylonitrile polymers differing in hydrophilic properties, 2) bicomponent filaments of both of said polymers having one interface between polymers components and 3) bicomponent filaments of both of said polymers having more than one interface between polymer components. This fiber, however, in spite of its composition of numerous filaments of differing structure provides a tow bundle having a desirable level of reversible crimp measured in a manner specific to the type of crimp designated.Also disclosed is a method for wet-spinning the novel fiber using a static mixing unit in conjunction with a spinnerette normally used for wet-spinning monocomponent filaments.

Abstract: Use of special pin insert in the counterbore-orifice combination of a conventional spinnerette plate provides open structure fibers.

Abstract: Using a conventional spinneret plate with suitable pins inserted in the counterbore-orifice combination thereof, hollow fibers are provided.

Abstract: A spinnerette plate having multiple capillaries per counterbore can be effectively used to melt-spin fusion melts of acrylonitrile polymer and water without sticking together of individual filaments.

Abstract: Use of special pin insert in the counterbore-orifice combination of a conventional spinnerette plate provides open structure fibers.

Abstract: A process for preparing an acrylonitrile polymer fiber is disclosed wherein melt-spun acrylonitrile polymer filaments are maintained in a stretchable state as spun, stretched in at least two stages while maintained in such stretchable stage, the first stage being at a stretch ratio of up to about 5 and the subsequent stretch being at a stretch ratio greater than that of said first to provide a total stretch ratio of at least about 25.

Abstract: A monolobal acrylonitrile polymer fiber is disclosed in which a continuous hollow extends throughout the fiber length, which hollow is surrounded completely by a solid polymer composition substantially devoid of sheathcore structure, density gradient, and void structure, said fiber being less than about 50 deniers per filament and having desirable textile properties.

Abstract: Using a conventional spinneret plate with suitable pins inserted in the counterbore-orifice combination thereof, hollow fibers are provided.

Abstract: By blocking part of a spinnerette orifice with a wire strand desirable cross-sectional shaped fibers of acrylonitrile polymer are obtained.

Abstract: A spinnerette plate having multiple capillaries per counterbore can be effectively used to melt-spin fusion melts of acrylonitrile polymer and water without sticking together of individual filaments.

Abstract: Melt-spinning of a fusion melt of an acrylonitrile polymer and water through a crowded hole spinnerette plate having small orifice diameters is achieved using low molecular weight polymer to provide fiber of desirable physical properties.

Abstract: Fusion melts of acrylonitrile polymer and water are effectively melt-spun through spinnerettes of high capillary density without sticking together of the individual filaments.