Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/12—Stretch-spinning methods
  • D01D5/16—Stretch-spinning methods using rollers, or like mechanical devices, e.g. snubbing pins
• • 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
• • 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
  • Y10T428/2927—Rod, strand, filament or fiber including structurally defined particulate matter
• • 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

• HMLS threads made of polyester and spin stretching process for their production
• the invention relates to HMLS threads made of polyester with a tensile strength of> 70 cN / tex, a L ⁇ SE 5 of> 35 cN / tex and a hot air shrinkage at 160 ° C of 1.5-3.5% and a spin stretching process Production of the HMLS threads.
• HMLS threads are understood to mean multifilament stretched polyester threads with high modulus and low shrinkage (high modulus,] _ow shrinkage).
• Multifilament polyethylene terephthalate filaments with high L ⁇ SE 5 the specific force which corresponds to an elongation of 5% in the force-elongation diagram
• Stretch ratio decreases, the steepness of the force-elongation diagram, d. H. the L ⁇ SE 5 rises, the thermal shrinkage decreases and the achievable strength decreases.
• the decrease in the applicable stretching ratio is due to the increase in the orientation in the filament and is characterized by an increase in the birefringence of the filament.
• the stretching ratios that can be used for the different spinning speeds are so low that efficient top speeds of over 6000 m / min are only possible at very high spinning take-off speeds of over 3500 m / min.
• a polyester thread is produced at spinning take-off speeds of 2500 to 4000 m / min.
• the low stretchability even at spinning take-off speeds of 4000 m / min, gives high speeds of just 6000 m / min for high-speed spinning draws, the tensile strength being less than 65 cN / tex.
• Drawn yarns with tensile strengths above 70 cN / tex and low thermal shrinkage, produced at spinning speeds above 2500 m / min, are also described in EP 0526 740 B. These yarns consist of a polyester raw material based on a copolymerization modified polyethylene terephthalate. These modification components are incorporated into the polymer chain during the polymer formation process, which impairs the flexibility of the spinning operation.
• Acrylic acid and / or maleic acid or their derivatives can be increased without addition to the elongation at break of polyester filaments spun under the same conditions.
• Information on the production of HMLS threads in the spin stretching process is not included.
• EP 0631 638 B describes fibers composed predominantly of PET, which contains 0.1-5% by weight of a 50-90% imidized polymethacrylic acid alkyl ester. The fibers obtained and subsequently finally drawn at speeds of 500-10,000 m / min are said to be higher Have initial module. In the examples of industrial yarns, however, the influence on the module cannot be easily understood; in general, the strengths achieved are low, which is a considerable disadvantage for this product.
• the present invention has for its object to provide HMLS threads with a tensile strength> 70 cN / tex, a L ⁇ SE 5> 35 cN / tex and a hot air shrinkage at 160 ° C of 1.5 to 3.5%, and to create a spin-stretching process for their production, at which final speeds of over 6000 m / min can be reached, even with highly viscous polyester, and with a minimization of the number of capillary breaks.
• the desired HMLS threads should be able to be produced at high spinning speeds without chemical modification of the polyester raw material being necessary, which would reduce the flexibility of the spinning plant.
• polyester examples include poly (C 2 _ 4 alkylene) terephthalates, which up to 15 mol% of other dicarboxylic acids and or diols, such as.
• Polyethylene terephthalate with an intrinsic viscosity (IV) in the range from 0.8 to 1.4 dl / g is preferred, Polypropylene terephthalate with an IV of 0.9 to 1.6 dl / g and polybutylene terephthalate with an IV of 0.9 to 1.8 dl / g.
• Usual additives such as dyes, matting agents, stabilizers, antistatic agents, lubricants, branching agents, can be added to the polyester or polyester additive mixture in amounts of 0 to 5.0% by weight without disadvantage.
• the additive polymers to be added to the polyester can have a different chemical composition.
• Three different types of polymer are preferred, namely
• R lt R 2 and R 3 are each an H atom or a C 15 alkyl radical or a C 5 12 cycloalkyl radical or a C 6 14 aryl radical,
• polymer from 15 to 100 wt .-% C and 0 to 85 wt .-% D, preferably from 50 to 95 wt .-% C and 5 to 50 wt .-% D and particularly preferably from 70 to 85 wt. -% C and 15 to 30 wt .-% D, the sum of C and D together making 100%.
• a polymer which contains the following monomer units:
• R is an H atom or a CH 3 group and R' or a C 5 .
• F styrene or C 1-4 alkyl-substituted styrenes
• R 15 R 2 and R 3 are each an H atom or a C 1-15 alkyl radical or a C 5.12 cycloalkyl radical or a C 5 . 14 -
• H one or more ethylenically unsaturated monomers copolymerizable with E and / or with F and / or G from the group consisting of ⁇ -methyl styrene, vinyl acetate,
• Acrylic acid esters methacrylic acid esters other than E, vinyl chloride, vinylidene chloride, halogen-substituted styrenes, vinyl esters, isopropenyl ethers and dienes,
• the polymer consisting of 30 to 99% by weight E, 0 to 50% by weight F,> 0 to 50% by weight G and 0 to 50% by weight H, preferably 45 to 97% by weight E, 0 to 30% by weight F, 3 to 40% by weight G and 0 to 30% by weight H and particularly preferably consists of 60 to 94% by weight of E, 0 to 20% by weight of F, 6 to 30% by weight of G and 0 to 20% by weight of H, the sum of E, F, G and H together results in 100%.
• Component H is an optional component. Although the advantages to be achieved according to the invention can already be achieved by polymers which have components from groups E to G, the advantages to be achieved according to the invention also occur if further monomers from group H are involved in the construction of the polymer to be used according to the invention.
• Component H is preferably selected so that it has no adverse effect on the properties of the polymer to be used according to the invention.
• Component H can u. a. can be used to modify the properties of the polymer as desired, for example by increasing or improving the flow properties when the polymer is heated to the melting temperature, or to reduce residual color in the polymer or by using a polyfunctional monomer to do so and to introduce some degree of crosslinking into the polymer.
• H can also be chosen so that a copolymerization of components E to G is possible or supported in the first place, as in the case of MA and MMA, which do not copolymerize per se, but copolymerize without problems when a third component such as styrene is added.
• Suitable monomers for this purpose include u. a. Vinyl esters, esters of acrylic acid, for example methyl and ethyl acrylate, esters of methacrylic acid which differ from methyl methacrylate, for example butyl ethacrylate and ethylhexyl methacrylate,
• the color reduction of the polymer can, for example, particularly preferably be achieved by using an electron-rich monomer, such as, for example, a vinyl ether, vinyl acetate, styrene or ⁇ -methyl styrene.
• Particularly preferred among the compounds of component H are aromatic vinyl monomers, such as styrene or ⁇ -methyl styrene.
• the preparation of the polymers to be used according to the invention is known per se. They can be prepared in bulk, solution, suspension or emulsion polymerization. Helpful hints can be found with regard to substance polymerization in Houben-Weyl, Volume E20, Part 2 (1987), page 1145ff. Information on solution polymerization can be found on page 1149ff, while the
• Emulsion polymerization is carried out and explained there on page 1150ff.
• Bead polymers whose particle size is in a particularly favorable range are particularly preferred in the context of the invention.
• the polymers to be used according to the invention are preferably in the form of particles with an average diameter of 0.1 to 1.0 mm.
• larger or smaller beads or granules can also be used, although smaller beads place special demands on logistics, such as conveying and drying.
• the imidized polymer types 2 and 3 can be prepared from the monomers using a monomeric imide or by subsequent complete or, preferably, partial imidization of a polymer containing the corresponding maleic acid derivative. These additive polymers are obtained, for example, by completely or preferably partially reacting the corresponding polymer in the melt phase with ammonia or a primary alkyl or arylamine, for example aniline (Encyclopedia of Polymer Science and Engineering Vol 16 [1989], Wiley-Verlag, page 78). All of the polymers according to the invention and, if given, their non-imidized starting polymers are commercially available or can be prepared by a process which is familiar to the person skilled in the art.
• the concentration c of the polymeric additive in% by weight in the polyester is determined as a function of the specified take-off speed v in m / min and the desired birefringence of the filament ⁇ n according to the following formulas:
• ⁇ n birefringence of the polyester filament according to the invention with additive added
• the additive polymer is incompatible with the polyester, which means that the additive is largely insoluble in the polyester matrix.
• the polyester and the additive polymer form two phases that can be distinguished microscopically.
• the copolymer must have a glass transition temperature (determined by DSC at 10 ° C / min
• Heating rate 90 to 170 ° C and can be processed thermoplastically.
• the melt viscosity of the copolymer should be chosen so that the ratio of its extrapolated to the measuring time is zero
• melt viscosity measured at an oscillation rate of 2.4 Hz and a temperature which is equal to the melting temperature of the polyester plus 34.0 ° C (for polyethylene terephthalate 290 ° C) relative to that of the polyester, measured under the same conditions, between 1: 1 and 7: 1. That is, the melt viscosity of the polymer is at least equal to or preferably higher than that of the polyester.
• Optimal efficiency is only achieved by choosing a specific viscosity ratio of additive and polyester. With such an optimized viscosity ratio, it is possible to minimize the amount of additive additive, which makes the process particularly economical.
• the viscosity ratio determined according to the invention as ideal for the use of polymer mixtures for the production of HMLS threads is above the range which is indicated in the literature as being favorable for mixing two polymers.
• polymer blends with high molecular weight additive polymers were distinguished to spin.
• the flow activation energy (E) is a measure of the rate of change of the zero viscosity as a function of the change in the measuring temperature, the zero viscosity being the viscosity extrapolated to the shear rate 0.
• a particularly narrow particle size distribution of the additive in the polyester matrix is achieved and by combining the viscosity ratio with a flow activation energy of significantly more than that of the polyester (PET about 60 kJ / mol), i.e. H.
• the fibril structure of the additive in the filament is obtained at more than 80 kJ / mol.
• the glass transition temperature which is high compared to polyester, ensures that this fibril structure is quickly consolidated in the spun thread.
• the maximum particle sizes of the additive polymer are about 1000 nm immediately after emerging from the spinneret, while the average particle size is 400 nm or less. After warping below the spinneret and stretching, fibrils with an average diameter ⁇ 80 nm are formed.
• the ratio of the melt viscosity of the copolymer to that of the polyester under the above-mentioned conditions is preferably between 1.5: 1 and 5: 1. Under these conditions, the average particle size of the additive polymer is 120-300 nm immediately after it emerges from the spinneret, and this results Fibrils with an average diameter of approximately 40 nm.
• the additive polymer is mixed with the matrix polymer by adding it as a solid to the matrix polymer chips in the extruder inlet with a chip mixer or gravimetric metering, or alternatively by melting the additive polymer, metering by means of a gear pump and feeding it into the melt stream of the matrix polymer.
• a homogeneous distribution is then produced by mixing using a static mixer.
• a specific particle distribution is set by the specific choice of mixer and the duration of the mixing process before the melt mixture is passed on through product distribution lines to the individual spinning stations and spinnerets.
• Mixers with a shear rate of 16 to 128 sec "1 have proven successful.
• the product of the shear rate (s " 1 ) and the 0.8th power of the residence time (in sec) should be at least 250, preferably 350 to 1250. Values above 2500 are generally avoided in order to keep the pressure drop in the pipes limited.
• the shear rate is defined by the shear rate in the empty tube (s "1 ) times the mixer factor, the mixer factor being a characteristic parameter of the mixer type. For Sulzer SMX types, for example, this factor is about 7-8.
• the shear rate ⁇ in the empty tube is calculated according to
• F delivery rate of the polymer (g / min)
• V 2 inner volume of the empty pipe (cm 3 )
• R empty pipe radius (mm)
• ⁇ empty volume fraction (for Sulzer-SMX types 0.84 to 0.88)
• ⁇ nominal density of the polymer mixture in the Melt (about 1.2 g / cm 3 )
• Both the mixing of the two polymers and the subsequent spinning of the polymer mixture takes place at temperatures, depending on the matrix polymer, in the range from 220 to 320 ° C., preferably at (melting temperature of the matrix polymer + 34) + 25 / - 20 ° C. , Temperatures of 270 to 315 ° C. are preferably set for PET.
• the molten polymer mixture is pressed through the holes in the nozzle plate.
• the melt threads are in the subsequent cooling zone cooled below its solidification temperature by means of cooling air, so that sticking or upsetting on the following thread guide member is avoided.
• the cooling air can be supplied from a climate system by transverse or radial blowing.
• the spinning threads are subjected to spin preparation, drawn off at a defined speed via godet systems, then drawn, heat-set and finally wound up.
• thread interlacing devices can be included in the process.
• the properties of the additive polymer and the mixing technology cause the additive polymer to form spheroidal or elongated particles in the matrix polymer immediately after the polymer mixture emerges from the spinneret.
• the best conditions were found when the mean particle size (arithmetic mean) d 50 ⁇ 400 nm and the proportion of particles> 1000 nm in a sample cross-section was less than 1%.
• the influence of these particles by the spinning draft or the drawing could be verified analytically.
• New investigations of the threads by the TEM method transmission electron microscopy have shown that there is a fibril-like structure.
• the mean diameter of the fibrils was estimated at approximately 40 nm and the length / diameter ratio of the fibrils was> 50.
• the drawing is carried out in a manner known per se in at least one stage between differently heated godet systems, preferably in two stages.
• the stretching of the spinning thread is preferably carried out using a draw ratio DR, for which the Withdrawal speed v in m / min and the concentration c of the additive copolymer in% by weight applies:
• DR is the product of the individual stretching ratios.
• the winding speed is equal to the product of the spinning speed v, the draw ratio DR and the relax ratio.
• the HMLS threads according to the invention have at least the same quality values as yarns produced analogously without polymeric additive.
• Additive fibrils The microtome thin sections of the threads were examined by means of transmission electron microscopy and subsequent image analysis, in which the diameter of the fibrils was assessed and the length was estimated from the particle diameter determined in samples immediately after the spinneret.
• the intrinsic viscosity was determined on a solution of 0.5 g polyester in 100 ml of a mixture of phenol and 1,2-dichlorobenzene (3: 2 parts by weight) at 25 ° C. To determine the melt viscosity (initial viscosity), the polymer was dried in vacuo to a water content of ⁇ 1000 ppm (polyester ⁇ 50 ppm). The granules were then introduced into the temperature-controlled measuring plate in a cone-plate rheometer, type UM100, Physica Meßtechnik GmbH, Stuttgart / DE, while being coated with nitrogen. The measuring cone (MK210) was positioned on the measuring plate after the sample had melted, ie after approx. 30 seconds.
• the measuring temperature was 290 ° C. for polyethylene terephthalate and additive polymers to which polyethylene terephthalate was added, or was equal to the melting temperature of the polyester concerned plus 34.0 ° C.
• the measuring temperature thus determined corresponds to the typical processing or spinning temperature of the respective polyester.
• the amount of sample was chosen so that the rheometer gap was completely filled.
• the measurement was carried out in oscillation with the frequency 2.4 Hz (corresponding to a shear rate of 15 sec "1 ) and a deformation amplitude of 0.3, and the amount of the complex viscosity was determined as a function of the measurement time.
• the initial viscosity was then determined by linear regression converted to zero measurement time.
• the polyester sample was first melted at 310 ° C. for 1 minute and immediately quenched to room temperature. The glass transition temperature and the melting temperature were then determined by DSC measurement (differential scanning calorimetry) at a heating rate of 10 ° C./min. Pretreatment and measurement were carried out under nitrogen blanketing.
• the birefringence of the filament ( ⁇ n) was determined using a polarizing microscope with a tilt compensator and green filter (540 nm) using wedge cuts. The path difference between the ordinary and the extraordinary beam when linearly polarized light passed through the filament was measured. The birefringence is the quotient of the path difference and the filament diameter. In the spinning stretching process, the spun thread was removed after the take-off godet.
• the strength properties of the fibers were determined on threads to which a twist of 50 T / m was applied, on a test length of 250 mm with a take-off speed of 200 mm / min.
• the force which corresponds to a strain of 5% in the force-strain diagram divided by the titer, is referred to as LASE-5.
• a polyethylene terephthalate with an intrinsic viscosity of 0.98 dl / g was used to produce the HMLS yarn.
• Example 8 a copolymer of 78% by weight of styrene and 22% by weight of imidized maleic anhydride with a glass transition temperature of 168 ° C. was used as an additive.
• the Polyester chips and the additive polymer were melted in a 7E extruder from Barmag, DE. The additive was dosed into the filler 1 piece of the extruder.
• the polymer mixture was forced through static mixers at 160 bar and fed to a 40 cm 3 melt metering pump.
• the mixture was subjected to a shear rate of 23 sec "1.
• the product of the shear rate and the 0.8th power of the residence time in seconds was 475.
• the spinning pump conveyed the melt, which was heated to 298 ° C., into the Lurgi Zimmer spinning system BN 110 with a round spinneret package and ring nozzle (300 holes with a diameter of 0.4 mm).
• the melt throughput was 660 g / min at all settings. This corresponds to a titer of 1100 dtex at a winding speed of 6000 m / min.
• the nozzle pressure was 420 bar.
• the spun multifilament thread was cooled in a radial blowing system (outside to inside), applied with a ring oiler with spinning preparation and fed to a 1st unheated godet duo.
• the speed of this 1st duo is by agreement equal to the spinning take-off speed. Only for sampling for the determination of birefringence was the spinning thread already after this 1.
• the three heated duos had the following temperatures:
• the partial relaxation ratio between Duo 4 and Duo 3 was 0.995 in all cases.
• the other settings can be found in the table.
• the process parameters for the spinning process were identical in all examples. Based on the specified spinning speed and a desired birefringence, the range of additive polymer concentration to be used was calculated in accordance with equation 1, the factor x, depending on the additive, being used as 1 for Examples 3 to 7 and as 2.8 for Example 8. The actual concentration was chosen within the calculated range.
• the concentration of the additive polymer can be determined according to equation (1) according to the invention in such a way that the desired birefringence can be achieved at a given spinning speed.
• the choice of additive concentration according to the invention does not exceed the maximum value of the desired birefringence.
• relatively high spinning speeds can be set without this leading to a reduction in strength or to an excessive number of fiber defects leads, as is the case with the known methods disadvantageously.
• the mean diameter of the fibrils in the threads was below 80 nm.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Artificial Filaments (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
• Polyesters Or Polycarbonates (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7917844

Family Applications (1)

Country Status (10)

Families Citing this family (6)

Family Cites Families (7)

• 1999
  • 1999-08-10 DE DE19937728A patent/DE19937728A1/de not_active Withdrawn
• 2000
  • 2000-07-25 KR KR1020027001816A patent/KR20020036843A/ko not_active Application Discontinuation
  • 2000-07-25 AU AU64372/00A patent/AU6437200A/en not_active Abandoned
  • 2000-07-25 US US10/049,009 patent/US6740404B1/en not_active Expired - Fee Related
  • 2000-07-25 EA EA200200196A patent/EA004429B1/ru not_active IP Right Cessation
  • 2000-07-25 EP EP00951438A patent/EP1208253B1/fr not_active Expired - Lifetime
  • 2000-07-25 JP JP2001515364A patent/JP2003506587A/ja active Pending
  • 2000-07-25 CN CNB008116458A patent/CN1168856C/zh not_active Expired - Fee Related
  • 2000-07-25 AT AT00951438T patent/ATE275650T1/de not_active IP Right Cessation
  • 2000-07-25 DE DE50007704T patent/DE50007704D1/de not_active Expired - Fee Related
  • 2000-07-25 WO PCT/EP2000/007085 patent/WO2001011122A1/fr active IP Right Grant

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events