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
• • 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
  • D01F6/84—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyesters
• • 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
  • Y10T428/2915—Rod, strand, filament or fiber including textile, cloth or fabric
• • 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
  • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
  • Y10T442/60—Nonwoven fabric [i.e., nonwoven strand or fiber material]
  • Y10T442/608—Including strand or fiber material which is of specific structural definition
  • Y10T442/627—Strand or fiber material is specified as non-linear [e.g., crimped, coiled, etc.]
  • Y10T442/632—A single nonwoven layer comprising non-linear synthetic polymeric strand or fiber material and strand or fiber material not specified as non-linear
  • Y10T442/633—Synthetic polymeric strand or fiber material is of staple length

Definitions

• the present invention relates to yarns, fibers or filaments, having improved abrasion resistance, and in particular usable for the production of felts for paper machines. It relates more particularly to yarns, fibers or filaments based on polyamide or polyester.
• the properties which must be present in spun articles are different according to their use. Among these, there may be mentioned for example the mechanical resistance, the transparency, the gloss, the whiteness, the dyeability, the shrinkage, the water retention capacity, the fire resistance, the stability and the heat longevity ...
• a property which may be required, in particular for applications in industrial fields or in so-called technical wire fields, is abrasion resistance.
• felts which are composite structures comprising a stack of layers of woven fabrics (obtained from continuous monofilaments) and layers of nonwovens (obtained from cut fibers), the layers being assembled in general by needling.
• the increase in abrasion resistance generally makes it possible to increase the life of articles made from yarns, fibers or filaments.
• felts for paper machines which are made from synthetic fibers
• this property has become critical for many reasons: replacement of chemical bleaching agents by solid particles, for example calcium carbonate, increase in the speed of production or operating temperatures of paper machines that stress felts more critically.
• This is also the case, for example, for carpets and rugs, cords and belts, nets, fabrics used in the field of screen printing or filtration.
• a possible alternative, described in patents US 5,234,644 and US 5,783,501, consists in producing yarns or fibers of conventional molecular weights and then increasing, a posteriori (on the fiber in the case of US5234644 or on the felt in the case of US5783501), the viscosity of the polymers.
• This solution has limitations, however. Thus this adds an additional step in the process and requires the use of chemical solutions containing catalysts.
• Another known solution consists in spinning polymers of high molecular mass but which one seeks to reduce the melted viscosity. This can be obtained through the use of polymers comprising star macromolecular chains.
• the polymers comprising such star macromolecular chains are for example described in the documents FR 2,743,077, FR 2,779,730, US 5,959,069, EP 0.632,703, EP 0.682,057 and EP 0.832,149. These compounds are known to have improved fluidity compared to linear polyamides of the same molecular weight. However, the yarns, fibers or filaments obtained from these polymers do not have good abrasion resistance properties.
• Another solution for improving the abrasion resistance of articles made from fibers consists in using articles having a three-dimensional crimp, as described in patent CA 2076726.
• the object of the present invention is to propose another solution for obtaining spun articles with high abrasion resistance.
• the invention provides yarns, fibers and filaments resistant to abrasion obtained from a composition
• a composition comprising a polymer matrix, the polymer matrix consisting of a polycondensate consisting of: 30 to 100% molar (limits included) of macromolecular chains corresponding to the following formula (I): R3_ ( ⁇ _R 2 _ ⁇ ) n _ ⁇ _A-R 1 -AX- (YR 2 -X) m -R 3 (I) 0 to 70 mol% (limits included) of macromolecular chains having the following formula (II) in which -XY- is a radical resulting from the polycondensation of two reactive functions Fi and F 2 such that - F!
• A is a covalent bond or an aliphatic hydrocarbon radical which can comprise heteroatoms and comprising from 1 to 20 carbon atoms.
• - R2 is a branched or unbranched aliphatic or aromatic hydrocarbon radical comprising from 2 to 20 carbon atoms.
• R4 represents hydrogen, a hydroxyl radical or a hydrocarbon radical - R-
• the polymer matrix is a polyamide A1 consisting of: 30 to 100 mol% (limits included) of macromolecular chains corresponding to the following formula (I): R3- (XR 2 -Y) nXAR 1 -AX- (YR 2 -X) m -R 3 (I) 0 to 70 mol% (limits included) of macromolecular chains corresponding to the following formula (II) R 4 - [YR 2 -X] P -R 3 (II) in which:
• - Y is the radical - N - when X represents the radical - C -, R 5 O
• - Y is the radical - C - when X represents the radical N, OR 5 - A is a covalent bond or an aliphatic hydrocarbon radical which may comprise heteroatoms and comprising from 1 to 20 carbon atoms.
• R2 is a branched or unbranched aliphatic or aromatic hydrocarbon radical comprising from 2 to 20 carbon atoms.
• R3 represents hydrogen, a hydroxyl radical or a hydrocarbon radical
• R5 represents hydrogen or a hydrocarbon radical comprising from 1 to 6 carbon atoms
• - R- is a hydrocarbon radical comprising at least 2 carbon atoms, linear or cyclic, aromatic or aliphatic and which can comprise heteroatoms.
• -n, m and p each represent a number between 50 and 500, preferably between 100 and 400.
• the polymer matrix of the invention consists of a polyester A2 consisting of: - 30 to 100% molar (limits included) of macromolecular chains corresponding to the following formula (I): R 3. ( ⁇ .R 2 . ⁇ ) n . ⁇ .AR 1 -AX- (YR 2 -X) m -R3 (I) 0 to 70 mol% (limits included) of macromolecular chains corresponding to formula (II) next R 4 - [YR 2 -X] P -R 3 (H) in which:
• - Y is the radical when X represents the radical - C - O
• - Y is the radical - C - when X represents the radical O - A is a covalent bond or an aliphatic hydrocarbon radical which can comprise heteroatoms and comprising from 1 to 20 carbon atoms.
• R2 is a branched or unbranched aliphatic or aromatic hydrocarbon radical comprising from 2 to 20 carbon atoms.
• R3 represents hydrogen, a hydroxyl radical or a hydrocarbon radical
• ⁇ or O - R- is a hydrocarbon radical comprising at least 2 carbon atoms, linear or cyclic, aromatic or aliphatic and which can comprise heteroatoms.
• -n, m and p each represent a number between 50 and 500, preferably between 100 and 400.
• the polymer matrix of the invention can also be a copolyesteramide.
• m, n and p are between 100 and 400, in particular between 100 and 300.
• m, n and p can for example be between 120 and 240. It should be noted that the values of m and n can be equal.
• the values m, n and p can also be equal.
• R2 is a pentamethylene radical.
• the polyamide A1 or the polyester A2 of the invention advantageously comprises at least 45%, preferably at least 60%, even more preferably at least 80 mol% of macromolecular chains corresponding to formula (I).
• the polyamide A1 or the polyester A2 of the invention advantageously has a number molecular mass at least equal to 10,000 g / mol, preferably at least equal to 20,000 g / mol, more preferably at least equal to 25,000 g / mol.
• molecular weight by number of polyamide A1 or polyester A2 is meant the molecular weight by number weighted by the molar fractions of the two types of macromolecular chains of formulas (I) and (II).
• the yarns, fibers, filaments of the invention comprising in their polymer matrix polyamide A1 and / or polyester A2, have good abrasion resistance properties. They are in particular suitable for the manufacture of felts for paper machines.
• the use of polyamide A1 or polyester A2 makes it possible to spin at a lower temperature and / or at reduced pressure compared to the conditions which would be necessary in the absence of polyamide A1 or polyester A2. It is thus possible either to obtain threads which resist abrasion better, or to obtain fibers whose properties are similar, with a less restrictive process (in particular in processing temperature or in spinning pressure).
• the yarns, fibers and filaments according to the invention can contain all the additives usually used with such polymers, for example thermal stabilizers, UV stabilizers, catalysts, pigments and dyes, antibacterial agents.
• the polyamide A1 or the polyester A2 is obtained by copolymerization from a mixture of monomers comprising: a) a difunctional compound whose reactive functions are chosen from amines, carboxylic acids , alcohols, and their derivatives, the reactive functions being identical, b) the monomers of general formulas (Nia) and (IIIb) below in the case of polyamide A1 OR ' 2 ⁇ N X'-R' 2 -Y '( lll a ) or H
• carboxylic acid or carboxylic radical in the present invention is meant the carboxylic acids and their derivatives, such as acid anhydrides, acid chlorides, esters, nitriles etc.
• amine is meant amines and their derivatives.
• the monomers of formula (III a ) or (III b ) are preferably the polyamide monomers of the polyamide 6, polyamide 11, polyamide 12 etc. type.
• Examples of monomers of formula (III a ) or (III) which may be suitable in the context of the invention include caprolactam, 6-aminocaproic acid, lauryllactam etc. It can be a mixture of different monomers.
• examples of monomers of formula (III a ') or (III b ') which may be suitable in the context of the invention mention may be made of caprolactone, ⁇ -valerolactone, 4-hydroxybenzoic acid etc.
• the monomer mixture can also comprise a monofunctional monomer conventionally used in the production of polymers as chain limiter.
• the mixture of monomers can also include catalysts.
• the various compounds of the mixture can be introduced in dried form, advantageously with a moisture content of less than 0.2%, preferably less than 0.1%, and a mixture can be added.
• compound capable of catalyzing the polycondensation of the polyamide or of the polyester preferably in a concentration by weight of between 0.001% and 1%.
• the humidity can be measured according to the method of K. Fisher.
• catalysts preferably introduced in a concentration by weight of between 0.001% and 1%, can be chosen from phosphorous compounds, for example phosphoric acid, tris (2,4-d i-tert-buty I phenyl) phosphite (marketed by the company CIBA under the reference Irgafos 168), pure or mixed with N, N- hexamethylene bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamamide) (marketed by CIBA under the reference Irganox B 1171).
• the compound a) represents between 0.05 and 1 mol% relative to the number of moles of monomers of type b) or b '), preferably between 0.1 and 0.5 mol%.
• the copolymerization of the monomers is carried out under conventional conditions for the polymerization of polyamides obtained from lactams or amino acids.
• polyester A2 the copolymerization of the monomers is carried out under conventional conditions for the polymerization of polyesters obtained from lactones or hydroxy acids.
• the polymerization can comprise a finishing step in order to obtain the desired degree of polymerization.
• the polyamide A1 or the polyester A2 is obtained by melt-blending, for example using an extrusion device, a polyamide of the type of those obtained by polymerization of lactams and / or amino acids or of a polyester of the type obtained by polymerization of lactones and / or hydroxy acids and of a difunctional compound whose reactive functions are chosen from amines, alcohols, acids carboxylic and their derivatives, the reactive functions being identical.
• the polyamide is, for example, polyamide 6, polyamide 11, polyamide 12, etc.
• the polyester is, for example, polycaprolactone, poly (pivalolactone), etc.
• the difunctional compound is added directly to the polyamide or the polyester in the melt. .
• the difunctional compound represents between 0.05 and 2% by weight relative to the weight of polyamide or polyester.
• the various compounds of the mixture can be introduced in dried form, with advantageously a moisture content of less than 0.2%, preferably less than 0.1 %, for example in an extrusion device and a compound capable of catalyzing the polycondensation of the polyamide or of the polyester can be added, preferably in a concentration by weight of between 0.001% and 1%.
• This compound can be chosen from phosphorous compounds, for example phosphoric acid, tris (2,4-di-tert-butyl phenyl) phosphite (sold by the company CIBA under the reference Irgafos 168), pure or in mixture with N, N-hexamethylene bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamamide) (sold by CIBA under the reference Irganox B 1171).
• This compound can be added in powder form or in concentrated form in a polyamide matrix (masterbatch). The mixture of the different compounds can be implemented in a single or twin screw extrusion device.
• the difunctional compound of the invention is preferably represented by the formula (IV): X "-A-R1-AX".
• X represents an amino radical, a hydroxyl radical or a carboxylic group or their derivatives R1 and A are as described above.
• radical X there may be mentioned a primary amine radical , secondary amino etc.
• the difunctional compound can be a dicarboxylic acid.
• diacids mention may be made of adipic acid which is the preferred acid, decanoic or sebacic acid, dodecanoic acid, phthalic acids such as terephthalic acid, isophthalic acid.
• the difunctional compound can be a diamine.
• diamines mention may be made of hexamethylene diamine, methyl pentamethylenediamine, 4,4'-diaminodicyclohexylmethane, butane diamine, metaxylylene diamine.
• the difunctional compound can be a dialcohol.
• dialcohols examples include 1,3-propanediol, 1,2-ethanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and polytetrahydrofuran.
• the functional compound can be a mixture of a diamine and a dialcohol.
• the reactive functions of the difunctional compound are generally amines or carboxylic acids or derivatives.
• the reactive functions of the difunctional compound are generally alcohols or carboxylic acids or derivatives.
• the difunctional compound is chosen from adipic acid, decanoic or sebacic acid, dodecanoic acid, terephthalic acid, isophthalic acid, hexamethylene diamine, methyl pentamethylenediamine, 4,4'- diaminodicyclohexylmethane, butane diamine, metaxylylene diamine, 1, 3-propanediol, 1, 2-ethanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol and polytetrahydrofuran
• the polyamide A1 or the polyester A2 is obtained by melt-blending, for example using an extrusion device, a polyamide of the type of those obtained by polymerization of lactams and / or amino acids or of a polyester of the type of those obtained by polymerization of lactones and / or hydroxy acid, with a compound of formula (V): G
• the polyamide is for example polyamide 6, polyamide 11, polyamide 12.
• the polyester is for example polycaprolactone or poly (pivalolactone).
• the compound of formula (V) is added directly to the polyamide or polyester in a molten medium.
• the compound of formula (V) represents between 0.05 and 2% by weight relative to the weight of polyamide or polyester.
• the various compounds of the mixture can be introduced in dried form, with advantageously a moisture content of less than 0.2%, preferably less at 0.1%, for example in an extrusion device and a compound capable of catalyzing the polycondensation of the polyamide or of the polyester can be added, preferably in a concentration by weight of between 0.001% and 1%.
• This compound can be chosen from phosphorous compounds, for example phosphoric acid, tris (2,4-di-tert-butyl phenyl) phosphite (sold by the company CIBA under the reference Irgafos 168), pure or in mixture with N, N-hexamethylene bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamamide) (sold by CIBA under the reference Irganox B 1171).
• This compound can be added in powder form or in concentrated form in a polyamide matrix (masterbatch). The mixture of the different compounds can be implemented in a single or twin screw extrusion device.
• All the polymer chain couplers or the polymer chain extension agents known to a person skilled in the art, generally comprising two identical functions or two identical radicals, and reacting selectively either with the reactive amino functions or with the reactive alcohol functions, either with the reactive carboxylic acid functions of the polyamide or of the polyester, to form covalent bonds, can be used as compound of formula (V).
• the compound (V) can for example selectively react with the amine functions of the polyamide into which it is introduced. This compound will not react with the acid functions of the polyamide in this case.
• the spun articles, threads, fibers or filaments are produced according to the usual spinning techniques from a composition comprising a polymer matrix comprising at least the polyamide A1 or the polyester A2 described above.
• Spinning can be carried out immediately after the polymerization of the matrix, the latter being in molten form. It can be produced from a granule comprising the composition.
• the articles spun according to the invention can be subjected to all the treatments which can be carried out in stages subsequent to the spinning stage. They can in particular be stretched, textured, crimped, heated, twisted, dyed, sized, cut ... These additional operations can be carried out continuously and can be integrated after the spinning device or be carried out discontinuously. The list of post-spinning operations has no limiting effect.
• the invention also relates to articles comprising yarns, fibers and / or filaments as described above.
• the yarns, fibers, filaments according to the invention can be used in woven, knitted or non-woven form.
• the fibers according to the invention are in particular suitable for the manufacture of felts for paper machines, and in particular for the nonwovens of felts for paper machines.
• the yarns, fibers and filaments according to the invention can also be used as yarns for carpets. They can also be used, in particular monofilaments, for obtaining fabrics in the field of screen printing for printing transfers, or in the field of filtration.
• the yarns, fibers, filaments of the invention, and in particular the multi-strands can also be used in the manufacture of ropes, in particular climbing ropes, or of belts, in particular conveyor belts.
• the yarns of the invention can be used for the manufacture of nets, in particular fishing nets.
• the flow rate Q can be measured, in a completely equivalent manner on several levels.
• the flow rate Q is expressed in g / min
• the speed v is expressed in m / min.
• the activation energy E is equal to 60 kJ / mol (M.l. Kohan,
• FIG. 1 schematically represents the apparatus used for the abrasion resistance test.
• the reference 1 represents the wire, the reference 2 a ceramic bar, the reference 3 a mass of 3g, the reference 4 of water.
• a unitary filament is subjected to a pre-tension of 3 g.
• the wire is immersed in a water bath at 23 ° C.
• the bar is rotating at 300 revolutions / minute with a contact angle of the wire on the bar (clamping) of 90 °.
• the filament is first of all desensitized for 1 hour in a Soxhiet assembly in petroleum ether and then conditioned for 24 hours in a water bath at 25 ° C. The total number of turns is noted before the filament breaks. This number is divided by the unit title of the strand in order to get rid of the title of the strand which can vary from one test to another. In total, the experiment is repeated 30 times and the results are averaged.
• Comparative Examples A polyamide 6 Synthesis
• the polyamides 6 called A1, A2, A3 and A4 are synthesized. They have the following characteristics:
• the following table specifies the raw values (temperature, titre, pressure drop) as well as the renormalized values, that is to say brought back to a temperature constant (250 ° C) and a constant flow (corresponding to a titer of 200dtex for a call speed of 800m / min).
• the renormalization is carried out in accordance with the formula previously described.
• Drawing The drawing rate is adjusted so as to obtain, after drawing, the desired level of elongation at break: approximately 80%.
• the yarn thus obtained is always composed of 10 filaments.
• Comparative Examples B Polymer comprising star macromolecular chains Synthesis
• the star polyamides B1, B2, B3 are obtained by copolymerization from caprolactam in the presence of approximately 0.5 mol% of 2,2,6,6-tetra ( ⁇ - carboxyethyl) cyclohexanone, according to a process described in document FR 2743077. They have the following characteristics:
• Drawing The drawing rate is adjusted so as to obtain, after drawing, the desired level of elongation at break. It is always composed of 10 filaments.
• Examples 1-3 according to the invention Synthesis These polymers are obtained by polycondensation of caprolactam in the presence of adipic acid. They have the following characteristics:
• Example 4 Measurement of the abrasion resistance Table 1 below presents the characteristics in terms of fluidity and abrasion resistance of the comparative examples A, B as well as of the examples in accordance with the invention.
• Figure 2 is a graph representing on the abscissa the pressure drop during the crossing of the pack (expressed in bars), and on the ordinate the abrasion resistance (expressed in cycle / dtex).
• polymers A are represented by diamonds
• polymers B are represented by squares
• polymers 2-3 are represented by triangles.

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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)
• Paper (AREA)
• Braiding, Manufacturing Of Bobbin-Net Or Lace, And Manufacturing Of Nets By Knotting (AREA)
• Filtering Materials (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

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• 2003
  • 2003-07-25 FR FR0309155A patent/FR2857984B1/fr not_active Expired - Fee Related
• 2004
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  • 2004-07-23 EP EP04767768A patent/EP1649087A2/de not_active Withdrawn
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