Abstract: In producing nylon yarns having latent crimp by the process disclosed in U.S. Pat. No. 4,202,854, the polymer throughput (i.e. extrusion rate) is increased without sacrificing the amount of uniformity of the bulk resulting from development of the latent crimp by adding a nucleating agent, such as calcium fluoride, to the nylon prior to extrusion.

Abstract: A method for stopping and restarting the free-radical polymerization of vinyl monomers (e.g. acrylic monomers) without forming low molecular weight polymer is provided. These polymerizations utilize a Redox catalyst system comprising multivalent metal ions (e.g. iron ions) as promoter. The polymerizations are stopped by chelation of the iron present. Additional monomer is added to the polymerization to avoid formation of low molecular weight polymer. Upon restart metal ions are added to the polymerization mixture.

Abstract: A self-crimping multi-component polyamide filament is provided and a process for producing the filament. In its simplest form, the filament is composed of two components each of which comprises a polyamide of the same chemical composition and one of which contains a minor amount of a polyolefin admixed with the polyamide. The filament is formed by co-extruding the components to form a conjugate filament that is attenuated in the molten state, solidified and then collected. Attenuation of the filament in the molten state imparts self-crimping properties and molecular orientation to the filament.

Abstract: A self-crimping multi-component polyester filament is provided and a process for producing the filament. In its simplest form, the filament is composed of two components each of which comprises a polyester of the same chemical composition and one of which contains a minor amount of a polyolefin admixed with the polyester. The filament is formed by co-extruding the components to form a conjugate filament that is attenuated in the molten state, solidified and then collected. Attenuation of the filament in the molten state imparts self-crimping properties and molecular orientation to the filament.

Abstract: Nylon fibers having a soil-resistant coating comprising the reaction product of polymeric zirconium oxide and hydrocarboxylic acid or salt thereof, for example, sodium lactate. The coating is more durable than if the acid or salt thereof are omitted therefrom.

Abstract: A bulky, tangled, twisted singles yarn is provided having good bulk and aesthetics. The yarn also has exceptional column strength and resistance of bending and untwisting. The yarn is particularly useful as a sweater yarn or half-hose yarn. The yarn is produced by passing twisted singles yarn having latent bulk through a chamber wherein the yarn is tangled and heated by means of a heated fluid such as superheated steam.

Abstract: A bulky, heatset, tangled, twisted singles carpet yarn is provided having exceptional column strength and resistance to bending and untwisting. Cut pile produced therefrom has excellent tuft rigidity and endpoint definition. The yarn is produced by passing a bulked, twisted singles yarn through a chamber wherein the yarn is tangled and heatset with a heated fluid such as steam.

Abstract: Improvements in conventional ring spinning processes of the type wherein a strand of staple fibers if drafted, twisted and collected on a ring spinning frame are obtained by the added step of subjecting the strand to the twisting action of a pneumatic false twister between the drafting and collecting steps. The added step improves performance and/or permits the process to be operated at higher front roll delivery speeds for any given spindle speed without sacrificing performance. The higher delivery speeds results in improvements in the productivity of the process and the apparent value of staple yarn produced thereby.

Abstract: A method for determining the amount of copolymerized vinyl monomer in a acrylonitrile/vinyl monomer copolymer is provided. The method is based on the fact that increasing the vinyl monomer content of the copolymer reduces its melting point. The method consists of first determining the melting point of the copolymer while the copolymer is saturated with water. The presence of water reduces the melting point to a temperature below the range where thermal degradation of the copolymer occurs. The amount of copolymerized vinyl monomer in the copolymer can then be determined by comparing its melting point in the presence of water to that of corresponding copolymers in which the vinyl monomer content thereof is known and varies from copolymer to copolymer.

Abstract: An acrylic fiber having dispersed therein 2 to 10 weight percent of a colloidal silica having an average particle size of about 1 to 4 microns, with a mean particle size of 2-3, preferably about 2, microns. This acrylic fiber has excellent whiteness and moisture transport characteristics and fabrics made from it have an improved crispness of hand.

Abstract: Carpets are provided having a pile wherein the individual tufts of the pile are made from a plurality of continuous filament nylon yarns, at least one of which is composed of filaments having crimp (extant or latent) and the other yarn or yarns are composed of filaments having no crimp. Carpets of the invention, particularly velour carpets have improved tuft identity and are free from streaks.

Abstract: Certain fiber-forming aromatic polyamides having a high solubility in organic solvents used in their preparation are provided. The polyamides are prepared from diacid chlorides and from diamines containing sulfonate linkages by the low temperature solution polymerization technique. Fibers of the polyamides have a high modulus to tenacity ratio.

Abstract: Soil-resistant carpet yarns are provided by providing yarns coated with, for example, a fluorochemical and zirconium oxide. Such yarns when used in the manufacture of carpets retain their soil-resistant properties during the carpet dyeing and finishing operation; the zirconium oxide in some way promotes the retention of the fluorochemical on the yarn.

Abstract: A process for dissolving copper in an aqueous nylon salt solution without dissolving other substances is provided by applying an electrical potential between two copper electrodes immersed in the solution. Upon melt polymerization of the salt solution, copper is incorporated into the resulting nylon. The amount of copper dissolved in the solution can be closely monitored and controlled.

Abstract: Novel compounds produced by reacting 5-sulfoisophthalic acid or a salt thereof (e.g. the potassium salt) with a water soluble copper salt (e.g. cupric acetate monohydrate) are described. The compounds are effective antiozonants for polyamide fibers, particularly, when the fibers are dyed with disperse dyes. Generally, sufficient amounts of the compounds are incorporated into the fibers to provide from 10 to 100 ppm, on weight of fiber, of copper.

Abstract: An acrylic fiber having improved basic dyeability and the method for making the same wherein an acrylic polymer containing a sulfonated vinyl monomer as a part thereof is dissolved in a suitable solvent to form a spinning dope and a solution of a second or additive polymer dissolved in the same solvent is added to the dope which is then spun to form fibers. The second polymer is selected from the group consisting of cellulose triacetate, polymethyl methacrylate, polyvinyl chloride, a polyamide of hexamethylenediamine with 1,1,3-trimethyl-5-carboxy-3-(p-carboxyphenyl) indane and a polyamide of hexamethylene diamine with isophthalic acid. The spin dope will contain 10 to 35 weight percent of polymer solids, with the amount of the second or additive polymer being 0.5 to 25 weight percent of the total polymer solids. Fibers spun from the dope have enhanced basic dyeability. The method is effective only when the acrylic polymer contains a sulfonated vinyl monomer as part of the acrylic polymer backbone.

Abstract: Disclosed is an acrylic fiber having improved basic dyeability. The fiber is made by a process wherein a copolymer of an acrylic monomer and a sulfonated vinyl monomer is dissolved in a solvent to form a spinning dope and a solution of polystyrene in the same solvent is added to the dope prior to spinning the dope to form fibers. The polystyrene will be in the form of a separate phase dispersed throughout the spinning dope and the fibers formed from the dope. Fibers formed from this polystyrene-containing dope have improved basic dyeability.

Abstract: A bulky, heatset, tangle, twisted singles yarn is provided having exceptional column strength and resistance to bending and untwisting. Cut pile produced therefrom has excellent tuft rigidity and endpoint definition. The yarn is produced by passing a bulked, twisted singles yarn through a chamber wherein the yarn is tangled and heatset with a heated fluid such as steam.

Abstract: The method for making bicomponent filaments from two spin dopes wherein the dopes are assembled into alternating layers in a feed tube leading to a transition tube connected to a conventional spinnerette, the layers then being fed through the transition tube and the spinnerette to form filaments. The feed tube has a constant cross-sectional area along the length thereof and the transition tube has a parabolic configuration such that the linear flow rate of the assembled dope layers passing through the transition tube decreases at a uniform rate as the cross-sectional area of the stream of assembled layers is increased to the cross-sectional area of the spinnerette, to thereby maintain the distinctness of the interfaces of the layers and thus insure that good bicomponent filaments will be formed.

Abstract: An improved process for making point-bonded nonwoven fabric composed of crimped filaments is described. The process involves melt spinning a side-by-side bicomponent filament which develops crimp at precisely the right instant so as to provide a uniform, high quality nonwoven fabric having a soft hand and other desirable apparel qualities.