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
  • D01F6/88—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds
  • D01F6/92—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds of polyesters
• • 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
  • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
  • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
  • D01F8/14—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyester as constituent
• • 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 present invention relates to polyester compositions that can be processed into yarns with very high abrasion resistance and dimensional stability. These threads, in particular monofilaments, can be used, for example, in screens or in conveyor belts.
• polyester fibers for technical applications are in most cases subjected to high mechanical and / or thermal stresses during use.
• the material must have good dimensional stability and constancy of force-elongation properties over as long as possible usage periods.
• polyester-based manmade fibers have proven successful in such environments, when used in humid-hot environments, polyesters are prone to mechanical abrasion in addition to hydrolytic degradation.
• abrasion can have a variety of causes.
• the sheet forming screen or forming fabric is pulled in paper machines for dewatering suction boxes with the result of increased Siebverschl constituentes.
• screen wear occurs due to differences in speed between the paper web and the screen surface or between the screen surface and the surface of the drying drums.
• Tissue wear also occurs in other technical fabrics due to abrasion; e.g. in conveyor belts by grinding over fixed surfaces, in filter fabrics by mechanical cleaning and in screen printing fabrics by passing a squeegee over the screen surface.
• Multi-ply fabrics are used in the forming fabrics of modern paper machines.
• vacuum boxes are used on the underside of the sieve to accelerate the dewatering of the paper web by means of negative pressure.
• the contact surfaces of the edges of these suction boxes with the forming fabric are usually made of ceramic to prevent excessive wear on the suction boxes.
• monofilaments of polyamide e.g. made of polyamide 6 or polyamide 6.6. Otherwise, monofilaments of polyethylene terephthalate (hereinafter referred to as "PET"), of which the forming wire essentially consists, are predominantly used because of the higher dimensional stability.
• PET polyethylene terephthalate
• a proven design is the so-called interchangeable shot on the underside of the sieve: Here, an excess of a polyamide monofilament with the following PET monofilaments is used alternately. This achieves a compromise between abrasion resistance and dimensional stability.
• thermoplastic polyurethane TPU
• thermoplastic polyester such as polyethylene terephthalate isophthalate
• thermoplastic polyurethane having melting points of 200 to 230 ° C were used (see, eg EP-A-674.029 ).
• polyester compositions of crystalline thermoplastic polyester resins, polyester elastomers and sorbitan esters are made DE 691 23 510 T2 known. These are characterized by good moldability, in particular by a good release ability.
• polyester compositions containing an aromatic polycarbonate, a polyester derived from alkanediol and benzene dicarboxylic acids, and a polyester urethane elastomer or a polyether imide ester elastomer are known. These have improved flow properties while maintaining good mechanical properties.
• the object of the present invention is to provide a composition which can be processed into filaments having excellent abrasion resistance and high dimensional stability.
• the threads produced from this composition should have no or only a slight flattening at the Kröpfungsticianen when processing as tissue.
• the invention relates to melt-spun threads comprising a) a thermoplastic and elastomeric polyester copolymer containing repeating structural units derived from different diols, one of which is a polyether diol and b) a thermoplastic polyester copolymer containing repeating structural units derived from different dicarboxylic acids or their derivatives Derive polyester-forming derivatives.
• threads are generally understood to mean fibers of finite length (staple fibers), fibers of infinite length (filaments) and multifilaments composed thereof or secondary-spun yarns of staple fibers.
• the melt-spun threads are preferably used in the form of monofilaments.
• thermoplastic and elastomeric polyester copolymers a) can be made up of a wide variety of monomer combinations, provided one diol is a polyether diol and another diol has no polyether units.
• these are copolymers derived from mixtures of short-chain alcohols, for example aliphatic or cycloaliphatic diols having from two to ten carbon atoms, and from polyetherdiols, and also from dicarboxylic acids or their polyester-forming derivatives, such as dicarboxylic acid esters or dicarboxylic acid chlorides, aliphatic, cycloaliphatic and / or or aromatic groups.
• thermoplastic and elastomeric copolyester is to be understood as meaning a copolyester which, at room temperature, is comparable to the conventional elastomers, but can be plastically deformed under heat supply and thus exhibits a thermoplastic behavior.
• thermoplastic and elastomeric copolyesters have in some areas physical crosslinking points (eg secondary valence forces or crystallites) that dissolve when exposed to heat without the polymer molecules decomposing.
• These copolyesters are block copolyesters which have hard and soft segments within one molecule.
• thermoplastic and elastomeric polyether copolyesters are known per se.
• copolyesters which, in addition to polyethylene terephthalate, polycyclohexane dimethyl terephthalate, polyethylene naphthalate or especially polybutylene terephthalate units, have further units derived from aromatic and / or aliphatic and / or cycloaliphatic dicarboxylic acids, in particular adipic acid, secacic acid, terephthalic acid, cyclohexanedicarboxylic acid or Isophthalic acid, and derived from polyalkylene glycols, in particular polyethylene glycols.
• thermoplastic and elastomeric copolyesters a) are preferably diols, polyether diols and dicarboxylic acids, or correspondingly constructed polyester-forming derivatives.
• the main acid component of the copolyesters are terephthalic acid or cyclohexanedicarboxylic acid, but other aromatic and / or aliphatic or cycloaliphatic dicarboxylic acids may also be suitable, preferably para or trans aromatic compounds, e.g. 2,6-naphthalenedicarboxylic acid or 4,4'-biphenyldicarboxylic acid, and isophthalic acid.
• Aliphatic dicarboxylic acids e.g. Adipic acid or sebacic acid, are preferably used in combination with aromatic dicarboxylic acids.
• Typical suitable dihydric alcohols are aliphatic and / or cycloaliphatic diols, for example ethylene glycol, propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol or mixtures thereof.
• Preferred are aliphatic diols having from two to four carbon atoms, especially ethylene glycol and butanediol.
• Further preferred are cycloaliphatic diols, such as 1,4-cyclohexanedimethanol.
• the soft segments of this copolyester are formed by recurring structural units derived from polyether diols and dicarboxylic acids.
• the polyether diols are polyalkylene glycols, such as polyethylene glycol, polypropylene glycol or polybutylene glycol.
• Copolyesters which have recurring structural units which are derived from an aromatic dicarboxylic acid and an aliphatic diol and a polyalkylene glycol are preferably used as component a).
• thermoplastic and elastomeric copolyesters a) have recurring structural units derived from terephthalic acid, ethylene glycol and polyethylene glycol, terephthalic acid, butylene glycol and polyethylene glycol, terephthalic acid, butylene glycol and polybutylene glycol, naphthalenedicarboxylic acid, ethylene glycol and polyethylene glycol, naphthalenedicarboxylic acid, butylene glycol and polyethylene glycol of naphthalenedicarboxylic acid, butylene glycol and polybutylene glycol, of terephthalic acid, isophthalic acid, ethylene glycol and polyethylene glycol, of terephthalic acid, isophthalic acid, butylene glycol and polyethylene glycol, and of terephthalic acid, isophthalic acid, butylene glycol and polybutylene glycol.
• the fiber-forming thermoplastic polyester copolymers b) may be of any nature. As a rule, these are copolymers derived from alcohols and dicarboxylic acids or their polyester-forming derivatives, such as dicarboxylic acid esters or chlorides, which have aliphatic and / or cycloaliphatic and / or aromatic groups. These copolyesters contain no moieties derived from polyether diols; In other words, these copolyesters contain no combinations of Hard and soft segments.
• thermoplastic copolyesters are known per se. Building blocks of thermoplastic copolyesters b) are preferably diols and dicarboxylic acids, or correspondingly constructed polyester-forming derivatives.
• the main acid constituent of the polyesters is terephthalic acid or cyclohexanedicarboxylic acid together with other aromatic and / or aliphatic or cycloaliphatic dicarboxylic acids, preferably with para- or trans-aromatic compounds, e.g. 2,6-naphthalenedicarboxylic acid or 4,4'-biphenyldicarboxylic acid, and preferably with isophthalic acid and / or with aliphatic dicarboxylic acids, e.g. with adipic acid or sebacic acid.
• Typical suitable dihydric alcohols are aliphatic and / or cycloaliphatic diols, for example ethylene glycol, propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol or mixtures thereof.
• Preferred are aliphatic diols having from two to four carbon atoms, especially ethylene glycol and butanediol.
• Further preferred are cycloaliphatic diols such as 1,4-cyclohexanedimethanol.
• Examples of preferred components b) are copolyesters which, in addition to polybutylene terephthalate, polycyclohexane dimethyl terephthalate, polyethylene naphthalate or especially polyethylene terephthalate units, comprise further units derived from alkylene glycols, in particular ethylene glycol, and aliphatic and / or aromatic dicarboxylic acids, such as adipic acid, secacic acid or isophthalic acid.
• Particularly preferred components b) are copolyesters containing, in addition to recurring structural units of the polyalkylene terephthalate, recurring structural units of the polyalkylene adipate, polyalkylene sebacate or, in particular, of the polyalkylene isophthalate.
• Very particularly preferred components b) are copolyesters containing recurring structural units of the polyethylene terephthalate, repeating structural units of the polyethylene adipate, of the polyethylene sebacate or, in particular, of the polyethylene isophthalate.
• the proportion of the second acid component in the thread according to the invention is typically up to 25% by weight, based on the weight of the copolyester, preferably between 0.1% by weight and 20% by weight, more preferably between 8% by weight and 12% by weight.
• the amounts of components a) and b) in the fibers according to the invention can be selected within wide ranges.
• the fibers typically contain 10 to 90% by weight of component a) and 90 to 10% by weight of component b), in each case based on the total mass of the fiber.
• the content of component b) in the total weight of the thread is preferably between 40 and 95% by weight, more preferably between 50 and 85% by weight, and very particularly preferably between 65 and 75% by weight, and 100% by weight. missing part of the thread consists of component a).
• Further particularly preferred threads contain as component a) polyether polyesters having a Shore D hardness of from 35 to 90, preferably from 35 to 45.
• Still other particularly preferred threads have a free thermal shrinkage at 160 ° C of less than 6%.
• the fiber according to the invention may also comprise further thread-forming thermoplastic polymers c), such as polyesters, for example PET, and / or polyamides.
• the proportion of this component c) is in generally low and should not exceed 10% by weight, based on the total mass of the fiber.
• the polyesters of components a) and b) used according to the invention usually have solution viscosities (IV values) of at least 0.60 dl / g, preferably from 0.60 to 1.05 dl / g, particularly preferably from 0.62 to 0, 93 dl / g, (measured at 25 ° C in dichloroacetic acid (DCE)).
• IV values solution viscosities
• Threads of polyesters with a content of free carboxyl groups of less than or equal to 3 meq / kg are preferred.
• These preferably contain a means for occluding free carboxyl groups, for example a carbodiimide and / or an epoxide compound.
• Such treated polyester yarns are stabilized against hydrolytic degradation and are particularly suitable for use in humid-hot environments, especially in paper machines or as a filter.
• polyesters a) and b) used according to the invention gives the polyester threads excellent abrasion resistance without adversely affecting the dynamic properties or their dimensional stability.
• the components a) and b) required for producing the threads according to the invention are known per se, some are commercially available and can be prepared by processes known per se.
• the threads according to the invention may contain, in addition to components a), b) and optionally c), further auxiliaries d).
• hydrolysis stabilizer Processing aids antioxidants, plasticizers, lubricants, pigments, matting agents, viscosity modifiers or crystallization accelerators.
• processing aids are siloxanes, waxes or longer-chain carboxylic acids or their salts, aliphatic, aromatic esters or ethers.
• antioxidants are phosphorus compounds, such as phosphoric acid esters or sterically hindered phenols.
• pigments or matting agents examples include organic dye pigments or titanium dioxide.
• viscosity modifiers are polybasic carboxylic acids and their esters or polyhydric alcohols.
• the threads according to the invention can be in any desired form, for example as multifilaments, as staple fibers, as secondary spun yarns, also in the form of twisted yarns, or in particular as monofilaments.
• the titer of the threads according to the invention can vary within wide limits. Examples are 1 to 45,000 dtex, in particular 100 to 4,000 dtex.
• the cross-sectional shape of the threads according to the invention may be arbitrary, for example round, oval or n-cornered, where n is greater than or equal to 3.
• the threads of the invention can be prepared by methods known per se.
• the threads according to the invention are drawn one or more times in the production.
• the hot polymer filament is cooled, e.g. in a cooling bath, preferably in a water bath, and then wound up or peeled off.
• the removal speed is greater than the injection rate of the polymer melt.
• the yarn thus produced is then preferably subjected to a post-drawing, more preferably in several stages, in particular a two- or three-stage post-stretching, with a total draw ratio of 1: 3 to 1: 8, preferably 1: 4 to 1: 6.
• the take-off speed is usually 10 - 80 m per minute.
• the threads according to the invention are preferably used for the production of textile surface constructions, in particular of woven fabrics, spiral fabrics, laid or knitted fabrics. These textile surface constructions are preferably used in screens.
• Textile surface constructions containing the threads according to the invention are likewise the subject of this invention.
• fabrics which, in addition to the threads comprising components a) and b), contain further threads of polyester, for example PET threads.
• the threads according to the invention can be used in all industrial fields. They are preferably used in applications in which increased wear due to mechanical stress is to be expected. Examples include the use in screens or in conveyor belts. These uses are also the subject of the present invention.
• filaments of the invention in the form of monofilaments relates to their use as conveyor belts or as components of conveyor belts.
• the weight loss of tissue 1 (interchangeable) is to be regarded as standard.
• Tissue 2 with the pure PET deficit showed the low abrasion resistance that PET had over the shuttle.
• Fabrics 8 and 9 contain the polyetherester of higher hardness than blend in PET. Here, the abrasion was higher than the standard.
• the polyether ester of lower Shore hardness which was also present in the mixture with a copolyester of PET with isophthalic acid, was significantly more resistant to abrasion.
• the high doses of 35% -40% significantly improved the abrasion resistance of these fabric samples (Tissues 6 and 7) over the standard (Tissue 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)
• Woven Fabrics (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 2006
  • 2006-03-16 DE DE102006012048A patent/DE102006012048A1/de not_active Ceased
• 2007
  • 2007-02-27 EP EP07003957A patent/EP1835055A1/fr not_active Withdrawn
  • 2007-03-14 US US11/724,138 patent/US20070219323A1/en not_active Abandoned
  • 2007-03-15 JP JP2007066079A patent/JP2007247131A/ja not_active Withdrawn

Patent Citations (4)

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