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
  • D01F6/78—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products
  • D01F6/80—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyamides
  • D01F6/805—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyamides from aromatic copolyamides
• • 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
  • Y10T428/2904—Staple length fiber
• • 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
• • 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
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/2938—Coating on discrete and individual rods, strands or filaments
• • 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
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/2964—Artificial fiber or filament
  • Y10T428/2967—Synthetic resin or polymer
  • Y10T428/2969—Polyamide, polyimide or polyester

Definitions

• the present invention relates to fibers containing selected aromatic polyamides with high strength and high titers, processes for their production and their use, in particular for the production of fiber-reinforced composite materials.
• Aromatic polyamides - also known as aramids - are known fiber-forming materials with high chemical resistance. Aramid fibers are characterized above all by good mechanical properties, such as high strength and modulus.
• High titer aramid fibers are already known.
• WO-A-91/381 describes aramid fibers with titers of more than 1.7 tex.
• Further coarse titer fibers made from aramids are known from WO-A-92 / 12,279.
• WO-A-92 / 12,018 describes reinforced composites containing such fibers and from WO-A-92 / 12,285 a process for the plasma treatment of coarse titre aramid monofilaments is known.
• All of these publications describe fibers made from aramids which are spun from anisotropic solutions.
• a typical representative of such aramids is poly (p-phenylene terephthalamide).
• Aramids of this type can only be spun under complex conditions, for example from solutions of the aramide in concentrated sulfuric acid.
• fiber is to be understood in its broadest meaning within the scope of this invention, provided that it is coarse-titer fibers; These include, for example, continuous fibers (filaments), such as monofilaments or multifilaments, or staple fibers, preferably with staple lengths of 0.5 to 50 mm, or pulp.
• the individual filament titer of the fibers according to the invention is preferably 8 to 50 dtex, in particular 10 to 30 dtex.
• the strength of the fibers according to the invention is preferably 130 to 260 cN / tex, preferably 150 to 205 cN / tex.
• the fibers according to the invention have a low elongation at break, for example an elongation at break of less than 10%, preferably an elongation at break of 4 to 5%.
• the elastic modulus of the fibers according to the invention is usually high, the initial modulus is, for example, more than 30 N / tex, preferably 30 to 80 N / tex, based on 100% elongation.
• the single-filament titer of the fibers according to the invention is highly uniform.
• the thread uniformity or the titre uniformity of multifilament yarns or monofilaments is expressed by the so-called USTER value (DIN 53 817).
• USTER value DIN 53 817
• fiber assemblies or monofilaments are passed through a measuring element, which converts the fluctuations in mass of the fiber assembly or monofilament into an electrical signal proportional to them.
• the fibers according to the invention preferably have cV values between 1.0 and 6.0% (measured with the aid of the ®USTER tester 2-C from Zellweger-Uster AG, Uster, Switzerland), in particular cV values of 1.8 up to 5.0%.
• the cross-sectional shape of the individual filaments of the fibers according to the invention can be any, for example triangular, tri-or multilobal or in particular elliptical or round. Hollow fibers can also be produced.
• Suitable aramids for use in the production of the fibers according to the invention are all aramides which are soluble in organic solvents, as long as they form isotropic solutions.
• aromatic polyamide forming isotropic solutions is to be understood as a polymer which forms isotropic solutions at 25 ° C. in an organic solvent or a mixture of such solvents.
• Aromatic polyamides are preferably used which are soluble in polar aprotic solvents with the formation of isotropic solutions and which have at least two, in particular three, different recurring structural units which differ in the diamine units.
• the aramide is preferably a polymer which has the recurring structural units of the formulas I, II and, if appropriate, III -OC-Ar1-CO-NH-Ar2-NH- (I), -OC-Ar1-CO-NH-Ar3-NH- (II), -OC-Ar1-CO-NH-Ar4-NH- (III), wherein Ar1, Ar2, Ar3 and Ar4 independently represent a divalent mono- or polynuclear aromatic radical, the free valences of which are in the para-position or in the meta-position or in a parallel, coaxial or angled position comparable to these positions, and Ar2, Ar3 and optionally Ar4 in each case assume different meanings within the scope of the given definitions, and the respective monomer units on which the polymer is based are selected such that an aromatic polyamide which forms soluble and isotropic solutions in organic solvents is obtained.
• radicals mean divalent aromatic radicals, the valence bonds of which are in para- or in a comparable coaxial or parallel position to one another, these are mono- or polynuclear aromatic hydrocarbon radicals or heterocyclic-aromatic radicals which can be mono- or polynuclear.
• heterocyclic-aromatic radicals these have in particular one or two oxygen, nitrogen or sulfur atoms in the aromatic nucleus.
• Polynuclear aromatic radicals can be condensed with one another or linearly connected to one another via C-C bonds or via -CO-NH groups.
• valence bonds which are in a coaxial or parallel position, are directed in opposite directions.
• An example of coaxial, oppositely directed bonds are the biphenyl-4,4'-ylene bonds.
• An example of parallel, opposite bonds are the naphthylene 1,5 or 2,6 bonds, while the naphthylene 1,8 bonds are parallel aligned.
• Examples of preferred divalent aromatic radicals are mononuclear aromatic radicals with mutually para-free valences, in particular 1,4-phenylene or dinuclear fused aromatic radicals with parallel directed bonds, in particular 1,4-, 1,5- and 2,6-naphthylene, or dinuclear aromatic residues linked via a CC bond with coaxial, oppositely directed bonds, in particular 4,4'-biphenylene.
• radicals mean divalent aromatic radicals whose valence bonds are in a meta- or in a comparable angled position to one another, then these are mono- or polynuclear aromatic hydrocarbon radicals or heterocyclic-aromatic radicals which can be mono- or polynuclear.
• heterocyclic aromatic Residues have in particular one or two oxygen, nitrogen or sulfur atoms in the aromatic nucleus.
• Polynuclear aromatic radicals can be condensed with one another or via C-C bonds or via bridging groups, e.g. -O-, -CH2-, -S-, -CO- or -SO2- be connected to each other.
• Examples of preferred divalent aromatic radicals whose valence bonds are in a meta or in a comparable angled position to one another are mononuclear aromatic radicals with free valences which are meta to one another, in particular 1,3-phenylene or dinuclear condensed aromatic radicals with bonds oriented at an angle to one another, in particular 1,6- and 2,7-naphthylene, or dinuclear aromatic residues linked via a CC bond with bonds oriented at an angle to one another, in particular 3,4'-biphenylene.
• Smaller proportions for example up to 5 mol% of the monomer units, based on the polymer, can be aliphatic or cycloaliphatic in nature, for example alkylene or cycloalkylene units.
• Alkylene radicals are to be understood as meaning branched and in particular straight-chain alkylene, for example alkylene with two to four carbon atoms, in particular ethylene.
• Cycloalkylene radicals are, for example, radicals having five to eight carbon atoms, in particular cyclohexylene.
• Alkyl radicals are to be understood as meaning branched and in particular straight-chain alkyl, for example alkyl having one to six carbon atoms, in particular methyl.
• Alkoxy radicals are to be understood as meaning branched and in particular straight-chain alkoxy, for example alkoxy with one to six carbon atoms, in particular methoxy.
• radicals are halogen, it is, for example, fluorine, bromine or, in particular, chlorine.
• Aromatic polyamides based on unsubstituted radicals are preferred.
• Examples of preferred diamine combinations on which these preferred recurring structural units of the formulas I, II and III are based are 1,4-phenylenediamine, 4,4'-diaminodiphenylmethane and 3,3'-dichloro-, 3,3'-dimethyl- or 3,3'-dimethoxybenzidine; as well as 1,4-phenylenediamine, 1,4-bis (aminophenoxy) benzene and 3,3'-dichloro-, 3,3'-dimethyl or 3,3'-dimethoxybenzidine; as well as 1,4-phenylenediamine, 3,4'-diaminodiphenyl ether and 3,3'-dichloro, 3,3'-dimethyl or 3,3'-dimethoxybenzidine; as well as 1,4-phenylenediamine, 3,4'-diaminodiphenyl ether and 4,4'-diaminobenzanilide; and 1,4-phenylenediamine, 1,
• Aramides which are derived from such diamine combinations and which can preferably be used according to the present invention are described in EP-A-199,090, EP-A-364,891, EP-A-394,892, EP-A-394,893 and EP-A- 424,860.
• aromatic polyamides to be used according to the invention are known per se and can be produced by processes known per se.
• Aromatic polyamides are preferably used which have the recurring structural units of the formulas I, II and optionally III defined above, in which Ar1 is a divalent mono- or polynuclear aromatic radical, the free valences of which are in the para position or in a position comparable to this position are parallel or coaxial to each other, Ar2 represents a divalent mono- or polynuclear aromatic radical, the free valences of which are in the p-position or in a parallel or coaxial position comparable to this position, Ar3 represents a radical of formula IV -Ar5-X-Ar6- (IV), in which Ar5 and Ar6 independently of one another represent a divalent mono- or polynuclear aromatic radical, the free valences of which are in the para position or in a parallel or coaxial position comparable to this position, or in which Ar6 additionally a divalent mono- or polynuclear aromatic radical whose free valences are in the meta position or in an angular position comparable to this position, X is
• aramids of this type are polymers in which Ar1 is 1,4-phenylene, Ar2 is 1,4-phenylene or a divalent radical of 4,4'-diaminobenzanilide, Ar5 and Ar6 are 1,4-phenylene, X is -O- , -CH2- or - O-1,4-phenylene-O- and Ar4 is a divalent radical of 3,4-diaminodiphenyl ether, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine or 3,3'- Represents dimethoxybenzidine.
• the polycondensation of aromatic polyamides to be spun according to the invention is generally carried out as solution polymerization.
• the aromatic monomeric diamines are dissolved in an amide solvent.
• the solution thus obtained is then mixed with the at least one aromatic monomeric compound in the form of an aromatic dicarboxylic acid dihalide with vigorous stirring in order to initiate the polycondensation.
• the amide solvent is used not only as a solvent for the aromatic monomeric compounds and the aromatic copolyamide obtained therefrom, but also as an acid acceptor for a hydrogen halide, e.g. for hydrogen chloride, which is produced as a by-product of the copolymerization of the aromatic monomeric compounds.
• a solubility-promoting additive for example a metal halide of one of the metals of group I or II of the periodic system, which is added to the polycondensation mixture before, during or after the polycondensation.
• alkali metal halides such as lithium chloride
• alkaline earth metal halides such as calcium chloride
• the polycondensation temperatures in solution polymerization are usually between -20 ° C and + 120 ° C, preferably between + 10 ° C and + 100 ° C. Particularly good results are achieved at reaction temperatures between + 10 ° C and + 80 ° C.
• the sum of the concentrations of the aromatic monomeric compounds in the polycondensation mixture solution can be adjusted taking into account the desired degree of polycondensation, the desired viscosity of the polycondensation mixture, the type of aromatic monomeric compounds used, the type of solvent used and the desired polycondensation temperature.
• the most favorable sum of the concentrations can be determined on the basis of a series of preliminary tests for the course of the polycondensation.
• Polycondensation reactions are preferably carried out such that 2 to 15, preferably 3 to 12% by weight of polycondensate are present in the solution after the reaction has ended. Particularly good results are achieved at concentrations of 4 to 6% by weight.
• a sufficient molecular chain length is achieved if the viscosity of the polymer solution obtained in the polycondensation has an inherent viscosity of the polymer of more than 3.0 dl / g, preferably more than 5.0 dl / g, in particular 4.5 to 8.0 corresponds to dl / g.
• ⁇ rel means the relative viscosity, c the concentration used in g / 100 ml.
• the polycondensation can be carried out in the usual way by adding monofunctional compounds, e.g. Acetyl chloride can be stopped.
• monofunctional compounds e.g. Acetyl chloride
• the hydrogen chloride formed and bound to the amide solvent in salt form can then be neutralized by adding basic substances.
• Suitable for this are, for example, lithium hydroxide, calcium hydroxide, but especially calcium oxide.
• the aromatic polyamide obtained when the production process is carried out can be separated from the polycondensation mixture by a separation process, for example by precipitation.
• a separation process for example by precipitation.
• the aromatic polyamide thus obtained is then dissolved in a suitable organic solvent, this process being referred to as the dissolution process for producing the spinning solution.
• a solvent of the amide type is preferably used as the solvent, in particular the solvents of the amide type mentioned above, or a mixture of two or more of the compounds mentioned.
• the concentration of the aromatic polyamide is kept in a range between 3 and 12% by weight, in particular between 4 and 6% by weight.
• the spinning solution can contain an additive to promote solubility, wherein at least one metal halide of a metal of groups I and II of the periodic table can be used, for example lithium chloride, calcium chloride or magnesium bromide, in a concentration between 0.2 and 10%, preferably between 0.5 and 5%, based on the total weight of the spinning solution.
• the additive to promote solubility also promotes the stability of the spinning solution at elevated temperature.
• the spinning solution can be spun into the fibers according to the invention by any suitable dry process, wet process or dry-wet process.
• the spinning solution is extruded through a spinneret into a coagulating liquid.
• the coagulation liquid consists of water or an aqueous solution containing a polar organic solvent.
• the polar organic solvent can be selected from the same amide solvents that are usually used for dissolving the aromatic polyamide.
• the same organic solvent which is contained in the molding solution is preferably used as the polar organic solvent in the coagulation liquid.
• the coagulation liquid is preferably used at a temperature between 0 ° C. and the boiling temperature of the coagulation liquid at atmospheric pressure.
• the polar organic solvent is preferably present in the coagulation liquid in a concentration between 70% by weight and less, in particular less than 50% by weight.
• the spinning solution is extruded through a spinneret with one or more spinning orifices, the filamentary streams of the spinning solution being solidified in one of the coagulation liquids specified above (wet process) or in an atmosphere which promotes evaporation (dry process).
• dry-jet wet spinning process is another suitable variant.
• the size of the nozzle holes of the spinneret should be chosen so that a filament of the desired titer results.
• spinnerets with nozzle hole diameters of 0.1 to 1.0 mm are used. These spinnerets can have individual nozzle holes (production of monofilaments) or also several nozzle holes (production of multifilaments).
• the viscosity of the spinning solution is to be adjusted so that a particularly uniform delivery rate of the spinning pump can be achieved.
• the coagulation is preferably carried out using a coagulation liquid with an additive for promoting coagulation, this coagulation being followed by a further coagulation step in the course of which the coagulating filaments of the aromatic polyamide are introduced into a water bath which is at a temperature is kept between 0 and 100 ° C.
• the additional coagulation step serves to complete the coagulation by removing the solvent.
• additives for promoting coagulation, if such substances are used, are washed out of the coagulated filaments.
• aromatic polyamide according to the invention can easily be processed into filaments using conventional spinning processes and devices without the use of a dangerous or harmful solvent, such as e.g. concentrated sulfuric acid, should be used.
• a dangerous or harmful solvent such as e.g. concentrated sulfuric acid
• the filaments made from the copolyamide according to the invention have a dense internal structure.
• the filaments produced according to the invention are usually subjected to a drawing process, by which not only the mechanical properties, e.g. tensile strength and modulus of elasticity, but also thermal properties, such as the thermal stability of the fibers thus produced.
• the stretching can be carried out in a single step, in two steps or in several steps, wherein a heating plate or a cylindrical heating device can be used for heating.
• the drawn filaments can be subjected to further heat treatment at the same or higher temperature in order to promote their crystalline structure.
• the fibers according to the invention are distinguished by high tensile strengths and initial moduli and by low elongation at break.
• Step c) can be an evaporation of the solvent using an elevated temperature, so that a low-solvent shaped structure is formed which has sufficient mechanical stability and freedom from tack for further processing (dry molding process).
• Step c) is preferably an introduction of the primary shaped structure into a bath containing a coagulation liquid, so that the organic solvent is removed from said primary shaped structure and the desired shaped structure is formed by coagulation of the primary structure, one for the further Processing has sufficient mechanical stability (wet molding process).
• the introduction can take place by direct extrusion into a coagulation liquid or by extrusion into a coagulation liquid after passing through an air gap of a predetermined length.
• An aromatic polyamide based on terephthalic acid dichloride, 25 mol% para-phenylenediamine, 50 mol% 3,3'-dimethylbenzidine and 25 mol% 1,4-bis (4-aminophenoxy) benzene is dissolved in NMP by solution polycondensation prepared so that the solution has an inherent viscosity of about 6 dl / g.
• the polymer solution obtained is spun directly through a 10-hole nozzle using the wet spinning process.
• the nozzle hole diameters are 150 to 300 ⁇ m.
• the filaments are precipitated in an aqueous precipitation bath containing 35% by weight of NMP at 80 ° C. and then washed in two water baths and a washing machine at 80 ° C.
• the infeed and outfeed godets (14 m / min and 16 m / min) run at different speeds.
• the filaments are then passed over a dry pallet and finally over an iron at temperatures of 490 to 430 ° C and drawn 19 times.
• the single filament titer of the filaments obtained is 10 dtex.
• the filaments have the following mechanical properties: fineness-related strength: 133 cN / tex Starting module: 66 N / tex, Elongation at break: 2.1%
• the infeed and outfeed godets (14 m / min and 16 m / min) run at different speeds.
• the filament is then passed over a dry pallet and finally over an iron at temperatures of 400 to 480 ° C and stretched 12 times.
• the filament has the following mechanical properties: fineness-related strength: 203 cN / tex Starting module: 51 N / tex, Elongation at break: 4.1%

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Polyamides (AREA)
• Woven Fabrics (AREA)

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• 1993
  • 1993-10-06 DE DE4334004A patent/DE4334004A1/de not_active Withdrawn
• 1994
  • 1994-09-27 AT AT94115184T patent/ATE176806T1/de not_active IP Right Cessation
  • 1994-09-27 DE DE59407824T patent/DE59407824D1/de not_active Expired - Fee Related
  • 1994-09-27 ES ES94115184T patent/ES2128480T3/es not_active Expired - Lifetime
  • 1994-09-27 EP EP94115184A patent/EP0647731B1/fr not_active Expired - Lifetime
  • 1994-10-04 JP JP6240100A patent/JPH07150413A/ja active Pending
• 1996
  • 1996-05-28 US US08/657,008 patent/US5698324A/en not_active Expired - Fee Related

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