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
  • D01F6/58—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products
  • D01F6/62—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products from polyesters
• • 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
  • D01D5/08—Melt spinning methods

Definitions

• This invention relates to a process for production of polyester multi-filament drawn yarn of 2.5 denier per filament or greater, whereby high birefringence ( ⁇ n) yarns are prepared at lower spinning speeds and lower intrinsic viscosity than prior art processes.
• Polyethylene terephthalate filaments of high strength are well known in the art and are commonly utilized in industrial applications including tire cord for rubber reinforcement, conveyor belts, seat belts, v-belts and hosing.
• DSP Dimensionally stable polyester
• SWI sidewall indentations
• An additional objective is to make advanced DSP's having the strength and modulus equivalent to rayon at elevated tire service temperatures, while using up to 30 percent less material. While the current polyester tire cords have sufficient strength, their elevated temperature modulus is too low.
• Patent 4,101,525 to Davis et al. provides a high
• terminal modulus cords made -by present invention.
• the process of Saito et al. requires high spinning speeds. which makes it difficult to incorporate the Saito process into a continuous spin-draw process, whereas the present invention permits the use of lower spinning speeds whereby more readily available and/or less costly equipment can be used.
• a process for production of a dimensionally stable drawn polyethylene terephthalate multifilament yarn having filaments of at least 2.5 denier per filament comprising the steps of:
• steps a) through c) are performed under conditions to form a partially-oriented
• modulus at elevated temperature is the important parameter governing performance. Due to the highly crystalline nature of treated cords based on conventional or dimensionally stable tire yarns, the modulus retention (in percent) at elevated tire temperatures is essentially similar for all current commercial treated cords and for those of this invention when loss modulus peaks occur at 110°C or greater. Thus, room temperature measurement of LASE-5 is sufficient to establish meaningful differences in polyester cord dimensional stability.
• the polyester yarn contains at least 90 mol percent polyethylene terephthalate (PET). In a preferred embodiment, the polyester is substantially all
• the polyester may incorporate as copolymer units minor amounts of units derived from one or more ester-forming ingredients other than ethylene glycol and terephthalic acid or its
• polyethylene terephthalate units include glycols such as diethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, etc., and dicarboxylic acids such as isophthalic acid, hexahydroterephthalic acid, bibenzoic acid, adipic acid, sebacic acid, azelaic acid,
• the polymer may be polymerized in a separate operation or polymerized in a directly coupled continuous polymerization and direct melt spinning process.
• An important aspect of this invention permits obtaining high undrawn birefringence yarn without the need to utilize molecular weight enhancing additives such as multifunctional coupling agents exemplified by
• the multifilament yarn of the present invention commonly possesses a denier per filament of about 2.5 to 20 (e.g. about 3 to 10), and commonly consists of about 6 to 600 continuous filaments (e.g. about 20 to 400 continuous filaments).
• the denier per filament and the number of continuous filaments present in the yarn may be varied widely within the ranges of this invention as will be apparent to those skilled in the art.
• the multifilament yarn made by the process is particularly suited for use in industrial applications including rubber composites, ropes, cordage and tarps.
• the fibers are particularly suited for use in environments where elevated temperatures (e.g. 80°C to 110°C) are encountered.
• Undrawn birefringence ( ⁇ n u ) was determined using a polarizing light microscope equipped with a
• Intrinsic viscosity (IV) of the polymer and yarn is a convenient measure of the degree of polymerization and molecular weight. IV is determined by measurement of relative solution viscosity of PET sample in a mixture of phenol and tetrachloroethane (60/40 by weight) solvents. The relative solution viscosity is the ratio of the flow time of a PET/solvent solution to the flow time of pure solvent through a standard capillary. Billmeyer approximation (J. Polym. Sci. 4, 83-86 (1949)) is used to calculate IV according to
• C concentration in gm/100 ml.
• concentration was 1.3 gms/100 ml. It will be understood that IV is expressed in units of deciliters per gram
• the tensile properties referred to herein were determined on yarns conditioned for two hours through the utilization of an Instron tensile tester (Model TM) using a 10-inch gauge length and a strain rate of 120 percent per minute in accordance with ASTM D885. All tensile measurements were made at room temperature.
• Model TM Instron tensile tester
• Elongation at the specified load of 4.5 g/d ( E 4 . 5 ) is inversely related to modulus. It is particularly useful in that the sum E 4.5 + FS is a good indicator of dimensional stability for yarns processed under different relaxation levels. Lower sums (E 4.5 + FS) indicate better dimensional stability.
• Figures 1 and 2 illustrate apparatus which may be utilized to
• the spinnerette and a spinning filter.disposed between the spin pump and spinnerette.
• the spinnerette is designed for the extrusion of one or more ends of filaments, each end containing a plurality of filaments.
• spinnerette at a spinning temperature in the range of 285 to 320°C and at a desired polymer volumetic flowrate (Q, cmVmin/capillary), and are passed downwardly from the spinnerette into a delay zone, chamber 16, which
• preferably is a quiescent delay zone or a heated sleeve of a desired delay length preferably 1 to 40 inches, maintained at a desired heated sleeve temperature
• Yarn leaving chamber 16 is passed directly into the top of the quenching zone, apparatus 17, preferably a radial inflow quench.
• the quench chamber is an elongated chimney of conventional length for example 1 to 40 inches.
• Ends 14 and 15 of yarn are lubricated by finish applicator 18.
• a spinning finish composition is used to lubricate the filaments.
• finish applicator 18 was a lube roll which is rotated with the direction of the yarn movement. Other means of applying finish could also be used.
• the partially-oriented multifilament yarn withdrawn from the quenching zone for example to at least 85 percent of the maximum draw ratio. This can be accomplished either in an off-line drawing process or preferably in a continuous spin-draw process.
• the drawing may be multiple steps and include high
• ends 14 and 15 are then transported to spin draw panel 21.
• a typical configuration is shown in Fig. 2.
• ends 14 and 15, are all processed on the same single set of forwarding (first roll 1), drawing (rolls 2-3 and rolls 5-6) and relaxing rolls (rolls 7-8). From draw roll 2, the ends are passed through a steam impinging draw point localizing steam jet 4. From
• V is the spinning speed given in
• IV is the intrinsic viscosity of the undrawn yarn given in dl/g.
• Rf is a value characteristic of the additional processing variables other than V and
• R f is typically ⁇ 8 x 10 -3 , whereas for the process of this
• R f is ⁇ 9.0 x 10 -3 .
• R f values for example Rf > 15 x 10 -3 , are readily
• R f can be broken down into two more basic terms:
• R r is related to the retention in orientation after
• the core of the invention is in the R e term which is related to the effective polymer extension from flow orientation in the spinnnerette and draw-down in the spin column. The net result is substantial orientation even a moderate spinning speeds.
• the experimentally determined relationship is
• D is the spinnerette capillary diameter (inches) and Q is the polymer flow rate through the capillary expressed in cm 3 /min/capillary.
• Q is calculated using a polymer density of 1.2 gm/cm 3 .
• This invention also teaches the proper combination of D and Q to achieve R e of at least 10.5 x 10 -2 . More preferred, R e is at least 13 x 10 -2 .
• the extension rate per hole (Q) was 0.88 cm 3 /min.
• the filaments were passed through a 1 inch heated sleeve and then quenced in a radial quench stack.
• the spun yarn was subsequently drawn on a panel similar to figure 2, with roll 1 maintained at 90°C, the yarn drawn 1.5/1 to unheated rolls 2, 3 with a normal ambient temperature of 40-50°C, then drawn 1.6/1 from rolls 2 , 3 to rolls 5, 6 maintained at 200°C, the yarn was then relaxed to rolls 7, 8 at 1 to 1.5 percent. Rolls 7 and 8 had an operating temperature of 150°C.
• the drawn yarn was taken up at 2.98 km/min. Polymer thruput for the two ends was 85 lbs./hour.
• the drawn yarn was 1004 denier, 3.3 dpf, 17.5 lbs. breaking strength, 7.9 g/d tenacity, 10.6 percent ultimate elongation, 3.9 g/d
• R f and R e were 24 x 10 -3 and 19 x 10 -2 , respectively.
• Q was 1.3 cm 3 /min/cap.
• the spun yarn was first drawn 1.4/1 between rolls at 90°C and unheated rolls, then drawn 1.15/1 between these and rolls
• the drawn yarn was then relaxed at 3% to rolls maintained at 135°C.
• the yarn was taken up by a high speed winder at 4.60 km/min.
• the drawn yarn was
• Drawn dpf was 2.7 and R e was 11 x 10 -2 .

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• 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)
• Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)

Applications Claiming Priority (2)

Publications (2)

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• 1989
  • 1989-11-17 EP EP90902093A patent/EP0452405B1/de not_active Expired - Lifetime
  • 1989-11-17 WO PCT/US1989/005081 patent/WO1990007592A1/en not_active Ceased
  • 1989-11-17 BR BR898907870A patent/BR8907870A/pt not_active IP Right Cessation
  • 1989-11-17 KR KR1019900701964A patent/KR0140230B1/ko not_active Expired - Fee Related
  • 1989-11-17 ES ES199090902093T patent/ES2034855T3/es not_active Expired - Lifetime
  • 1989-11-17 AU AU49696/90A patent/AU635241B2/en not_active Ceased
  • 1989-11-20 CN CN89108756A patent/CN1021919C/zh not_active Expired - Fee Related
  • 1989-12-08 CA CA002004942A patent/CA2004942C/en not_active Expired - Fee Related
  • 1989-12-20 MX MX018788A patent/MX170066B/es unknown
  • 1989-12-27 TR TR90/0073A patent/TR25058A/xx unknown
• 1991
  • 1991-09-27 ID IDP38791A patent/ID1015B/id unknown

Non-Patent Citations (1)

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