Abstract:
The present invention concerns yarn comprising polymer, the polymer comprising imidazole groups, the yarn having a sulfur content of 0.01 to 3.0 percent by weight, based on weight of the yarn, the yarn having a tenacity of 30 cN/dtex (33.3 gpd) or higher.
Abstract:
The present invention concerns methods for removing sulfur from yarn comprising the steps of: a) contacting never-dried polymeric yarn with an aqueous base, the polymer comprising imidazole groups and said polymer comprising sulfur atoms characterized as being in the form of sulfate anions; b) contacting the yarn with an aqueous acid comprising a halide; and c) rinsing the yarn.
Abstract:
The present invention concerns fiber made from a polymer comprising imidazole groups, fiber further having: i) a halide anion, the halide anion being present in an amount of 0.05 to 20.1 weight percent, based on weight of fiber; and ii) sulfur, wherein the sulfur is present in the fiber in an amount of 0.05 to 3 weight percent.
Abstract:
The present invention concerns processes for reducing water in never-dried fiber comprising copolymer derived from the copolymerization of para-phenylenediamine, 5(6)-amino-2-(p-aminophenyl)benzimidazole; and terephthaloyl dichloride, the process having the following steps in a continuous process, (a) a step of drying a never-dried fiber at less than 100 C until the moisture content of the fiber is less than 60 weight percent; and (b) a step of further drying the fiber above 150° C. while the moisture content of the fiber is no more than 40 weight percent; and the fiber being further heated to at least 350° C. in either an additional continuous or separate step.
Abstract:
The present invention concerns methods for removing sulfur from a fiber made from a polymer comprising imidazole groups, said method comprising: a) contacting never-dried sulfate anion-containing polymeric-fiber with an halide-containing acid to displace at least a portion of the sulfate ions with halide anions; and b) rinsing the fiber to remove the displaced sulfate ions.
Abstract:
The present invention concerns methods for removing sulfur from a fiber made from a polymer comprising imidazole groups, said method comprising: a) contacting never-dried sulfate anion containing polymeric-fiber with an aqueous salt solution comprising halide anions to displace at least a portion of the sulfate anions with halide anions; and b) rinsing the fiber to remove displaced sulfate anions.
Abstract:
The present invention concerns processes for producing a yarn comprising polymer comprising imidazole groups, the process having the following steps: (a) spinning a solution of polymer in sulfuric acid to give rise to a plurality of dope filaments; (b) coagulating the plurality of dope filaments into a multi-filament as-spun yarn; and (c) washing the as-spun multi-filament yarn with an aqueous acid comprising a halide or an aqueous salt comprising a halide or combination thereof.
Abstract:
The present invention concerns methods for removing sulfur from yarn comprising the steps of: a) contacting never-dried polymeric yarn with an aqueous base, the polymer comprising imidazole groups and said polymer comprising sulfur atoms characterized as being in the form of sulfate anions; b) contacting the yarn with an aqueous acid solution of pH 5 or lower; and c) rinsing the yarn.
Abstract:
The present invention concerns methods for removing sulfur from a fiber made from a polymer comprising imidazole groups, said method comprising: a) contacting never-dried sulfate anion-containing polymeric-fiber with an halide-containing acid to displace at least a portion of the sulfate ions with halide anions; and b) rinsing the fiber to remove the displaced sulfate ions.
Abstract:
Disclosed are processes for preparing polyareneazole polymers characterized as providing polymer solutions having an inherent viscosity of at least about 22 dl/g at 30° C. at a polymer concentration of 0.05 g/dl in methane sulfonic acid. Polyareneazoles, filaments and yarns are also disclosed.