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: An acrylic multifilamentary material possessing an internal structure which is well suited for thermal conversion to high strength carbon fibers is formed via a specifically defined combination of processing conditions. The acrylic polymer while in substantially homogeneous admixture with appropriate concentrations (as defined) of C.sub.1 to C.sub.2 nitroalkane and water is melt extruded and is drawn at a relatively low draw ratio which is substantially less than the maximum draw ratio achievable. During the melt extrusion a C.sub.1 to C.sub.4 monohydroxy alkanol preferably also is present in the substantially homogenous admixture. The fibrous material which is capable of readily undergoing drawing next is passed through a heat treatment zone wherein the evolution of residual nitroalkane, monohydroxy alkanol and water takes place.

Abstract: An acrylic multifilamentary material possessing an internal structure which is well suited for thermal conversion to high strength carbon fibers is formed via a specifically defined combination of processing conditions. The acrylic polymer while in substantially homogeneous admixture with appropriate concentrations (as defined) of C.sub.1 to C.sub.2 nitroalkane and water is melt extruded and is drawn at a relatively low draw ratio which is substantially less than the maximum draw ratio achievable. During the melt extrusion a C.sub.1 to C.sub.4 monohydroxy alkanol preferably also is present in the substantially homogenous admixture. The fibrous material which is capable of readily undergoing drawing next is passed through a heat treatment zone wherein the evolution of residual nitroalkane, monohydroxy alkanol and water takes place.

Abstract: A process for the production of asymmetric, porous membranes is disclosed which comprises extruding liquified polymer in tubular form and while expanding said film during processing, subjecting it to conditions such that the inside and outside surfaces of the film receive distinct treatments.

Abstract: A process for the production of asymmetric, porous membranes is disclosed which comprises extruding liquified polymer in tubular form and while expanding said film during processing, subjecting it to conditions such that the inside and outside surfaces of the film receive distinct treatments.

Abstract: Equally biaxially oriented film is produced by extruding liquified polymer in tubular form, orienting the tubular film in the radial direction only and then either (1) equally orienting the radially oriented film in the longitudinal direction and drying the resultant equally biaxially oriented film while preventing any shrinkage thereof or (2) orienting the radially oriented film in the longitudinal direction to a degree less than said radial orientation but equal to the radial orientation remaining after the biaxially oriented film undergoes radial shrinkage upon drying thereof in the absence of radial shrinkage control and drying the resultant biaxially oriented film in the absence of radial shrinkage control.

Abstract: Incorporation of an N-vinylamide and polymerization initiator into a single phase fusion melt of a hydrophobic acrylonitrile polymer and water and polymerization of said monomer in situ provides a stable, transparent acrylonitrile polymer shaped article when said melt is extruded directly into a steam-pressurized solidification zone in which it is stretched, followed by drying under controlled conditions of temperature and humidity.

Abstract: Extrusion of a homogeneous single phase fusion melt of acrylonitrile polymer and water through a circular die into a steam-pressurized solidification zone enables the tubular film formed to be drawn longitudinally and expanded transversely to provide a biaxially oriented barrier film especially suitable for food wrapping.

Abstract: A mixture of (1) a single phase melt of water and a first acrylonitrile polymer containing at least 85% acrylonitrile and (2) a pure melt of a second acrylonitrile polymer containing from about 60-72% acrylonitrile is extruded through the orifices of a spinneret directly into a steam-pressurized solidification zone to provide a biconstituent fiber which is stretched while within the solidification zone.