Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
  • D01F6/02—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D01F6/18—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polymers of unsaturated nitriles, e.g. polyacrylonitrile, polyvinylidene cyanide
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
  • D01F11/04—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers
  • D01F11/06—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers of macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber

Definitions

• the invention relates to a process for the production of threads, fibers and structures formed therefrom from acrylic polymers, the thread-forming substance of which consists of acrylonitrile and monomer units copolymerizable with acrylonitrile and has carboxyl groups which have at least partially been converted into the salt form, and the threads and fibers obtained thereby.
• Acrylic polymer fibers containing salts of carboxyl groups are known.
• DE-OS 24 34 232 describes a process for the production of acrylic fibers with improved hygroscopicity, in which raw materials containing carboxyl groups are spun into fibers, the fibers are then crosslinked and the carboxyl groups are converted to the salt form in an aqueous alkaline medium.
• polymers with up to 12% acrylic acid (corresponding to 7.5% by weight COOH groups) or 15% methacrylic acid (corresponding to 7.8% by weight COOH groups) are used.
• the fibers obtained have good textile-technological properties, but because of the crosslinking they are not swellable or only to a very limited extent.
• DE-OS 23 58 853 describes a process for the production of fibers with high water swellability, in which spun fibers are crosslinked with hydroxylamine and then saponified in an aqueous alkaline medium.
• the fibers produced in this way occur in a strongly swollen form. If you dry these heavily swollen fibers or threads, you get a very brittle and in some cases also strongly bonded fiber material that cannot be further processed into textile structures such as yarns, knits or fabrics by the conventional method.
• Alkaline hydrolysis can also occur in alkaline water. containing organic solvents, such as glycol or glycerin.
• organic solvents such as glycol or glycerin.
• the products obtained in this way are also brittle in the dry state and cause problems in textile further processing (DE-OS 29 03 267).
• DE-OS 29 42 064 describes swellable acrylic fibers with a core-shell structure in which the shell is composed of a hydrophilic, carboxyl-containing crosslinked polymer and the core is composed of a normal acrylonitrile polymer and / or another polymer.
• the process described here in which the cladding layer is produced by alkaline hydrolysis in an aqueous medium, is very complex since the fibers are obtained in a strongly swollen state and have to be dried with high energy input.
• Threads and fibers the thread-forming substance of which consists of an acrylic polymer which contains, in addition to acrylonitrile units and other units copolymerizable with acrylonitrile, 10 to 30% by weight of carboxyl groups, are particularly suitable.
• Such threads and fibers can be obtained by spinning a polymer raw material according to the spinning processes customary for acrylic threads and fibers, the polymer raw material used being an acrylonitrile polymer or copolymer which has been partially saponified in the heterogeneous phase by dilute aqueous acids. A dilute aqueous sulfuric acid with a content of 40 to 50% by weight is particularly suitable for the saponification.
• Such threads and fibers made of carboxyl-containing acrylic polymers, their use and processes for their production are the subject of a parallel application on the same day.
• the method according to the invention can also be applied to previously formed structures such as, for example, wadding, nonwovens, yarns or other textile fabrics which contain fibers containing carboxyl groups.
• the swelling capacity can be precisely adjusted by the amount of bases applied.
• the reaction of the fibers and threads with free carboxyl groups with gaseous bases is a convenient method for converting the free carboxyl groups into the salt form.
• Particularly suitable bases are ammonia, hydrazine and basic reacting organic nitrogen compounds, which are evaporable. In this case, it is preferably possible to use compounds which are particularly suitable for. Temperatures below 200 0 C, possibly also under reduced pressure, can be evaporated.
• Monomethylamine, dimethylamine, trimethylamine, the corresponding ethyl, propyl, butyl, pentyl and hexylamines and also the corresponding mixed compounds such as methylethylamine or methylbutylamine can be used, for example.
• Amines which also carry other functional groups, such as, for example, 2-hydroxyethylamine or compounds in which the other functional group can in turn be an amine, such as, for example, 1,2-diaminoethane are also suitable.
• Cyclic, saturated or unsaturated nitrogen compounds such as pyrrolidine, pyrroline, pyrol, pyridine and their derivatives are also suitable.
• other basic organic compounds such as hydrazines can also be used.
• the fibers and filaments containing carboxyl groups can also be reacted in the anhydrous liquid phase with liquid bases or their solutions in anhydrous organic solvents.
• anhydrous organic solvents it is also possible to use non-volatile basic compounds such as sodium hydroxide or potassium hydroxide in alcoholic solutions or alcoholates dissolved in alcohols can also be used.
• the threads and fibers according to the invention are particularly suitable for use in the hygiene sector, for example for the production of baby diapers or tampons, as an admixture fiber in fiber or thread nonwovens such as for use as shoe lining, for air-permeable but waterproof fabrics, as filter material, as an artificial nutrient medium for plant crops, as a water-retaining agent for garden soils, as run-on or spacer threads in cables for transmitting messages in order to localize a possible water ingress and the use, for example in a mixture with other synthetic fibers or threads in the production of synthetic leather.
• the threads produced according to the invention in which the carboxyl groups are at least partially in the salt form, still have proper textile technology values. They can therefore be processed into shaped structures such as yarns, nonwovens, fiber slats, wadding, textile fabrics, etc., as long as care is taken to ensure that they do not come into contact with large amounts of water.
• the swellable threads and fibers according to the invention are notable for tensile strength of more than 10 cN / tex and knot strengths of more than 6 cN / tex. They can be further processed into wadding, yarns and fabrics with the aid of conventional textile technology processes, since their textile technology values correspond at least to those of wool.
• the swellability or water retention capacity can vary depending on the degree of salt formation further boundaries fluctuate.
• the water retention capacity can be set to values of, for example, 50 to 200%.
• values of the water retention capacity can be set from a few hundred to a few thousand percent.
• the swellable threads and fibers according to the invention have in their thread-forming substance about 10 to 30% by weight of carboxyl groups which have at least partially been converted into the salt form.
• Powdery acrylic polymers of 93.7% acrylonitrile, 5.8% methyl acrylate and 0.5% sodium methallylsulfonate were saponified heterogeneously with 46.2 to 48.2% sulfuric acids. The saponification was carried out under reflux for 2.5 hours. After the reaction solution had cooled, the polymer was filtered off, washed sulfate-free with water and then dried. The partially saponified acrylic polymers obtained were dissolved in dimethylformamide (DMF) to form spinning solutions and spun into threads using the spinning processes known from polyacrylonitrile. The threads were washed, stretched, finished, dried, post-stretched, crimped and then cut into staple fibers with a cutting length of 40 mm in the usual way.
• DMF dimethylformamide
• the fibers obtained showed the following properties: To determine the carboxyl group content, about 150 mg of the polymer were dissolved in 25 ml of dimethyl sulfoxide (DMSb), mixed with 60 ml of water and titrated potentiometrically with 0.1N sodium hydroxide solution. The factor of the sodium hydroxide solution was determined with oxalic acid, dissolved in 60 ml of water and mixed with 25 ml of DMSO.
• DMSb dimethyl sulfoxide
• the inside diameter of the cup was 1.8 cm, the height, calculated from the net, was 3.9 cm.
• the beakers were kept with their contents in deionized water for 1 hour, to which water 1 g per liter of the sodium salt of diisobutylnaphthalenesulfonic acid was added as a wetting agent. At the start of the liquid treatment, the samples were evacuated for 5 minutes to remove adhering air bubbles.
• the actual centrifugation was carried out using a laboratory centrifuge from HERAEUS CHRIST GmbH, type UJO.
• the containers and samples were centrifuged at 4000 rpm for 30 minutes each.
• the distance between the cup nets and the axis of the centrifuge was 8.5 cm.
• the centrifuged fiber samples were then weighed and then dried in a drying cabinet at 120 ° C. to constant weight. The weight difference between the wet and dried sample, divided by the dry weight, was given in percent as water retention.
• the staple fiber samples thus produced were further processed into card slivers and stored in this form overnight in glass containers filled with gaseous ammonia.
• the water retention, tear strength and knot strength were determined on the fiber samples.
• the values obtained are summarized in the following table.
• the fibers obtained according to the 4 examples were not glued together, the card slivers could be processed into yarns without difficulty.

Landscapes

• Textile Engineering (AREA)
• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Artificial Filaments (AREA)
• Chemical Or Physical Treatment Of Fibers (AREA)
• Nonwoven Fabrics (AREA)
• Woven Fabrics (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
• Knitting Of Fabric (AREA)
• Chemical Treatment Of Fibers During Manufacturing Processes (AREA)

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• 1980
  • 1980-09-13 DE DE3034660A patent/DE3034660C2/de not_active Expired
• 1981
  • 1981-09-08 EP EP81107049A patent/EP0047962B1/fr not_active Expired
  • 1981-09-08 DE DE8181107049T patent/DE3173137D1/de not_active Expired
  • 1981-09-10 JP JP56141816A patent/JPS5777312A/ja active Granted
• 1985
  • 1985-06-27 US US06/750,046 patent/US4600407A/en not_active Expired - Fee Related

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