Abstract Substantially single-phase compositions which are substantially partial or complete hydrates of an acrylonitrile polymer containing at least 40% acrylonitrile units can be shaped into filaments and films. The nitrile groups of the polymer are hydrated to a selected extent depending on the particular polymer used. Hydration occurs only within a certain elevated temperature range and under at least autogenous pressure. Also disclosed are films and filaments having novel structural features which are spun from the substantially single-phase compositions comprising polymers or copolymers of 80% or more acrylonitrile. The filaments are characterized by a sheath which has a density gradient in which the density increases toward the surface and, after drawing, by a unique luster source ratio related to reflective interfaces. Many of the filaments have surface striations and an optically microvoided core. The filaments contribute good hand and good water absorption properties to fabrics made therefrom.
Process for spinning fibers of an acrylonitrile polymer which comprises adding water to an acrylonitrile polymer that contains at least about 40 weight percent units of acrylonitrile, in an amount equivalent as a minimum to either 45% of that required to hydrate all the nitrile groups or 80% of that required to hydrate the coupled nitrile groups (on a 1/1 water molecule/nitrile group basis), whichever is larger, and as a maximum the amount combined as hydrate plus 7 weight percent water based on polymer, the total water not to exceed the amount necessary to hydrate all nitrile groups in the polymer and maintaining the resulting substantially single phase composition under at least autogenous pressure at a temperature ranging between about 25° C less to about 10° C more than the temperature of hydration as determined by Laser Raman Spectroscopy and then extruding the composition under pressure through an extrusion orifice to obtain acrylonitrile polymer filaments.
Claim 2
Dependent Claim
155 words
Process for spinning fibers of an acrylonitrile polymer which comprises adding water to an acrylonitrile polymer that contains at least about 40 weight percent units of acrylonitrile, in an amount equivalent as a minimum to either 45% of that required to hydrate all the nitrile groups or 80% of that required to hydrate the coupled nitrile groups (on a 1/1 water molecule/nitrile group basis), whichever is larger, and as a maximum the amount combined as hydrate plus 7 weight percent water based on polymer, the total water not to exceed the amount necessary to hydrate all nitrile groups in the polymer and maintaining the resulting substantially single phase composition under at least autogenous pressure at a temperature ranging between about 25° C less to about 10° C more than the temperature of hydration as determined by Laser Raman Spectroscopy and then extruding the composition under pressure through an extrusion orifice to obtain acrylonitrile polymer filaments.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the temperature range is 170°-190° C.