WO1994022936A1 - Traitement thermique rapide de fibres liquides cristallines - Google Patents

Traitement thermique rapide de fibres liquides cristallines Download PDF

Info

Publication number
WO1994022936A1
WO1994022936A1 PCT/US1994/000400 US9400400W WO9422936A1 WO 1994022936 A1 WO1994022936 A1 WO 1994022936A1 US 9400400 W US9400400 W US 9400400W WO 9422936 A1 WO9422936 A1 WO 9422936A1
Authority
WO
WIPO (PCT)
Prior art keywords
mole
monomer unit
fiber
gpd
modulus
Prior art date
Application number
PCT/US1994/000400
Other languages
English (en)
Inventor
William M. Pleban
Cherylyn Lee
Stefanos Lepeniotis
Benjamin G. Morris, Jr.
George L. Collins
Original Assignee
Hoechst Celanese Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hoechst Celanese Corporation filed Critical Hoechst Celanese Corporation
Publication of WO1994022936A1 publication Critical patent/WO1994022936A1/fr

Links

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
    • D01F6/84—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyesters
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
    • C08G69/44—Polyester-amides
    • 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
    • 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
    • D01F6/82—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from polyester amides or polyether amides

Definitions

  • This invention relates generally to fibers made from liquid crystalline polymers, and more specifically, to fibers having both high modulus and high strength made by rapid heat treatment at elevated temperatures.
  • liquid crystalline polymers can be made into fibers having high strength and high modulus. In general, the best properties are obtained by heating fibers at elevated temperatures for extended periods of time, generally 8 hours or longer.
  • the heat treatment increases the strength (tenacity) significantly without a corresponding increase in modulus.
  • U.S. Patent 4,183,895 discloses that fibers made from liquid crystalline polymers can be made into high strength fibers by heat treatment at temperatures near the melting point of the polymer for a time in the range of 5 seconds to several hours. This heat treatment results in fibers having improved tenacity. In a few examples, the modulus also increases to some extent. In the examples of polymers containing monomer repeat units derived from naphthalene, the modulus generally is relatively unchanged after heat treatment, with the highest final modulus after heat treatment being 553 gpd.
  • fibers having both high strength and high modulus can be made by heat treatment of certain liquid crystalline polymers for relatively short times.
  • Such fibers are made by melt spinning a liquid crystalline polymer consisting essentially of monomer units I, II, III, IV and optional V to yield an as-spun fiber, where
  • IV is terephthaloyl containing up to about 25% isophthaloyl
  • V is - Y - Ar - Z -
  • Ar is one or more divalent aromatic moieties selected from the group consisting of 1,3-phenylene, 1,4-phenylene, 4,4'-biphenylene, 2, 6-naphthylene and 2,7-naphthylene
  • Y is a divalent moiety selected from the group consisting of -NH- and -NR-
  • Z is a divalent moiety selected from the group consisting of -NH-, -NR-, and -0-
  • R is an alkyl or aryl moiety containing 1-6 carbon atoms.
  • the liquid crystalline polymer consists essentially of about 1 to about 15 mole % of monomer unit I, about 20 to about 70 mole % of monomer unit II, about 5 to about 40 mole % of monomer unit III, about 1 to about 40 mole % of monomer unit IV, and up to about 20 mole % of optional monomer unit V.
  • the as-spun fiber is heat treated for a time in the range of about 0.25 hours to about 7 hours at a temperature in the range from about 80°C below the melting point of the liquid crystalline polymer up to the melting temperature of the liquid - crystalline polymer to yield a heat treated fiber having a tenacity of at least about 20 gpd and a modulus of at least about 600 gpd as measured by ASTM test method D3822-79. Fibers made by the method disclosed herein are also claimed.
  • Figure 1 is a computer-generated contour plot of the modulus and tenacity of liquid crystalline poly(esteramide) fibers that have been subjected to heat treatment after spinning as a function of the heat treatment time and heat treatment temperature.
  • the poly(esteramide) is derived from 6-hydroxy-2-naphthoic acid (3.5 mole %) , 4-hydroxybenzoic acid (60 mole %) , 4,4'-biphenol (13.25 mole %) , terephthalic acid (18.25 mole %) and p-aminophenol (5 mole %) .
  • Figure 2 is a computer-generated contour plot of the modulus and tenacity of liquid crystalline polyester fibers that have been subjected to heat treatment after spinning as a function of the heat treatment time and heat treatment temperature.
  • the polyester is derived from 6-hydroxy-2-naphthoic acid (4 mole %), 4-hydroxybenzoic acid (60 mole %), 4,4'- biphenol (18 mole %) and terephthalic acid (18 mole %) .
  • a preferred polymer composition is a polyester consisting essentially of monomer units I, II, III and IV, with monomer unit IV being terephthaloyl.
  • this polyester composition contains about 2 to about 10 mole % of monomer unit I, about 40 to about 70 mole % of monomer unit II, about 10 to about 30 mole % of monomer unit III, and about 10 to about 30 mole % of monomer unit IV. More preferably, the amount of monomer unit I is about 3 to about 10 mole %.
  • a particularly preferred polyester consists essentially of about 4 mole % of monomer unit I, about 60 mole % of monomer unit II, and about 18 mole % each of monomer units III and IV. Polyesters having this composition are described in detail in commonly-assigned U.S.
  • Patent 4,473,682 This polyester is made by methods well known in the art, such as those disclosed in U.S. Patent 4,473,682.
  • the preferred method is melt acidolysis polymerization.
  • the phenolic groups are esterified to acetates, and polymerization proceeds through ester interchange as acetic acid by ⁇ product boils off.
  • 6-acetoxy-2-naphthoic acid, 4-acetoxybenzoic acid, 4,4'-diacetoxybiphenyl, and terephthalic acid are the preferred reactants.
  • it is more convenient to generate the acetates in situ by charging the monomers without prior acetylation along with a catalyst and sufficient acetic anhydride to acetylate the phenolic groups. Heating of the reactants leads first to acetylation of the phenolic groups followed by polymerization.
  • Catalysts for melt acidolysis polymerization are well known in the art.
  • the preferred catalyst is potassium acetate.
  • Polymerization occurs as the temperature is gradually increased.
  • the final part of the polymerization is completed by heating the molten polymer under vacuum to about 350°C with stirring until the desired molecular weight is achieved, as measured by inherent viscosity.
  • the polymer has an inherent viscosity (I.V.) of at least about 1.0 dl/g when measured at 60°C on a 0.1% solution (w/v) in 50/50 (v/v) hexafluoroisopropanol/pentafluorophenol. More preferably, the I.V. is in the range of about 6 to 9, with about 7 being particularly preferred.
  • a polyester with this composition has a melting point of about 355°-360°C and is melt spun in the temperature range of about 360°-375°C. Details on the melt spinning and heat treatment of this particular polymer are presented in Examples 38-59.
  • compositions consisting essentially of monomer units I, II, III, IV and V, with monomer unit IV being terephthaloyl and monomer unit V being derived from 4- aminophenol, as show A elow.
  • Monomer unit V is present in an amount of about 1 to about 20 mole % of all the monomer units. More preferably, the poly(esteramide) consists essentially of about 2 to about 10 mole % of monomer unit I, about 40 to about 70 mole % of monomer unit II, about 5 to about 30 mole % of monomer unit III, about 10 to about 30 mole % of monomer unit IV, and about 2 to about 10 mole % of monomer unit V.
  • a particularly preferred poly(esteramide) consists essentially of about 3.5% of monomer unit I, about 60 mole % of monomer unit II, about 13.25 mole % of monomer unit III, about 18.25 mole % of monomer unit IV, and about 5 mole % of monomer unit V.
  • the melting point of the particularly preferred poly(esteramide) is in the range of about 350°-355°C, and it is preferably melt spun in the range of about 350°C-370°C.
  • the inherent viscosity (I.V.) is at least about 1.0 dl/g when measured at 60°C on a 0.1% solution (w/v) in 50/50 (v/v) hexafluoroisopropanol/pentafluorophenol. More preferably, the I.V. is in the range of about 6 to 9 dl/g and most preferably is about 7 dl/g.
  • the preferred poly(esteramide)s are made by methods well known in the art.
  • the preferred method is melt acidolysis polymerization, analogous to that previously described for the preferred polyester except for the presence of additional monomer unit V, derived from 4-aminophenol.
  • This monomer unit is preferably introduced as N-acetyl-p-aminophenol.
  • Synthesis of this and related liquid crystalline poly(esteramide)s are described in commonly-assigned U.S. Application No. 07/687,801, now allowed, and commonly-assigned U.S. Patents 4,330,457, 4,351,917 and 4,351,918.
  • the polymers of the current invention are melt spun into fibers by conventional methods, but without the subsequent drawing steps that are utilized in the production of conventional fibers.
  • the molten polymer is extruded through an orifice in the molten state and taken up on a reel at a sufficient speed that the fiber is drawn down to the desired size (generally about 4 to about 7 denier) .
  • This fiber (referred to as the "as- spun" fiber) , rather than being subjected to subsequent drawing steps as is done with conventional fibers, is instead subjected to heat treatment, in which it is placed in a hot oven under an inert atmosphere (e.g., nitrogen) . The fiber is placed in the oven without applying stress. This can be done by suspending lengths of fiber between two points in the oven. Large quantities of fiber, including fiber in the form of yarn, can be heat treated by loosely winding the fiber onto a heat resistant bobbin and placing the whole bobbin in the oven.
  • the as-spun fibers can be heat treated to fibers having both high modulus and high tenacity by heating them at an elevated temperature for relatively short times. It has been found that the short heat treatment times are important because the tenacity and modulus decrease after excessive heat treatment. As stated previously, heat treatment can be carried out for a period of about 0.25 to about 7 hours when the heat treatment is carried out at a temperature within about 80°C of the melting point of the polymer. This results in a fiber having a tenacity of at least about 20 gpd and a modulus of at least about 600 gpd.
  • the upper limit for heat treatment is the melting temperature of the polymer. Because the fibers become sticky as the heat treatment temperature approaches the melting point, the practical upper limit is a few degrees below the melting point, at which temperature the fibers stick together.
  • the heat treatment time is about 0.5 to about 6 hours, and the heat treatment temperature is within about 70° of the melting point of the polymer. Most preferably, the heat treatment is carried out for about 1 to about 5 hours within about 60° of the melting temperature of the polymer.
  • Fibers treated in accordance with the more preferred heat treatment times and temperatures have a tenacity of at least about 24 gpd and a modulus of at least about 750 gpd, and those fibers treated in accordance with the most preferred heat treatment conditions have a tenacity of at least about 27 gpd and a modulus of at least about 900 gpd.
  • the fiber is preferably heat treated for about 0.25 to about 6 hours at a temperature within about 70° of the melting temperature of the polymer to yield a heat treated fiber having a tenacity of at least about 24 gpd and a modulus of at least about 750 gpd. More preferably, the fiber is heat treated for about 0.5 to about 5 hours at a temperature within about 60° to about 20° below the melting temperature of the polymer to yield a heat treated fiber having a tenacity of at least about 27 gpd and a modulus of at least about 900 gpd.
  • the heat treatment is preferably carried out for a time in the range of about 0.5 to about 7 hours within about 70° of the melting point of the polymer to yield a fiber having a tenacity of at least about 27 gpd and a modulus of at least about 800 gpd. More preferably, the heat treatment is carried out for a time of about 1 to about 6 hours at a temperature within about 60° of the melting point of the polymer to yield a fiber having a tenacity of at least about 29 gpd and a modulus of at least about 900 gpd.
  • the fibers taught herein can also be made and heat treated in the form of yarns, which comprise a multiplicity of individual fibers. Yarns can also be subjected to rapid heat treatment at elevated temperatures to achieve high modulus and high tenacity. The measured properties of the yarns are in general somewhat lower than those of single filament fibers, perhaps because of a difference in test methods.
  • an as-spun yarn made from a liquid crystalline polymer consisting essentially of monomer units I, II, III,- IV and optional V, where monomer unit
  • III makes up about 5 to about 40 mole % of the polymer
  • IV makes up about 1 to about 40 mole % of the polymer
  • V is present in an amount up to about 20 mole % of the polymer, can be heat treated for a time in the range of about 0.25 to about 7 hours at a temperature within about 80° of the melting point of the polymer to yield a heat treated yarn having a tenacity of at least about 18 gpd and a modulus of at least about 700 gpd as measured by ASTM test method D885.
  • the heat treatment is carried out for a time greater than about 0.5 hours but less than about 6 hours at a temperature within about 70° of the melting point of the liquid crystalline polymer to yield a heat treated yarn having a tenacity of at least about 19 gpd and a modulus of at least about 750 gpd.
  • heat treatment of the as-spun yarn is preferably carried out for a time in the range of about 0.25 hours to about 6 hours at a temperature in the range of about 70°C below the melting point up to the melting point of the polyester to yield a heat treated yarn having tenacity of at least about 18 gpd and a modulus of at least about 700 gpd as measured by ASTM test method D885.
  • the heat treatment is carried out for a time in the range of about 0.5 to about 5 hours at a temperature within about 60° of the melting point of the polyester to yield a heat treated yarn having a tenacity of at least about 19 gpd and a modulus of at least about 750 gpd.
  • the heat treatment is preferably carried out for a time in the range of about 0.5 hours up to about 7 hours at a temperature within about 70° of the melting point of the polymer to yield a heat treated yarn having a tenacity of at least about 24 gpd and modulus of at least about 700 gpd as measured by ASTM test method D885.
  • the heat treatment is carried out for a time in the range of about 1 hour to about 6 hours at a temperature within about 60° of the melting point of the poly(esteramide) to yield a yarn having a tenacity greater than about 26 gpd and a modulus greater than about 800 gpd.
  • the heat treatment described herein is carried out under an inert atmosphere to prevent degradation of the fiber through oxidation of the polymer.
  • suitable inert atmospheres are nitrogen, argon and helium. It may be possible during the latter stages of the heat treatment to include air in the atmosphere, as has been taught for the heat treatment of liquid crystalline polyesters in U.S. Patent 5,045,257. The use of air in place of an inert gas would offer economic advantages in processing.
  • the method of rapid heat treatment of liquid crystalline fibers described herein is extremely useful because it results in shorter processing times, which makes the overall process more economical.
  • the fibers themselves are useful in applications where high modulus and high strength are required, such as ropes and reinforcements for belts.
  • This example illustrates the preparation of a particularly preferred poly(esteramide) from a 6 mole reaction mixture of 4-hydroxybenzoic acid, 6-hydroxy-2- naphthoic acid, 4,4 ' -biphenol, terephthalic acid, and N-acetyl-p-aminophenol in the ratio 60.0:3.5:13.25:18.25:5.0.
  • the contents of the flask were heated while stirring at a rate of 75 rpm to 152°C over a period of 111 minutes at which time 100 ml of acetic acid had been collected.
  • the polymerization temperature was then gradually raised to 350°C over a period of 215 minutes, at which time a total of 660 ml of acetic acid had been collected.
  • the flask was evacuated to a pressure of less than 1.0 mm at 350°C while stirring.
  • the polymer was stirred at 350°C until the desired change in torque was achieved. During this period the polymer melt continued to increase in viscosity while the remaining acetic acid was removed from the flask.
  • the resulting poly(esteramide) had an inherent viscosity (I.V.) of 9.0 dl/g as determined in a hexafluoroisopropanol/pentafluorophenol solution (50/50, v/v) of 0.1 percent (w/v) concentration at 60°C, and a melt viscosity of 365 poise at a shear rate of 10 3 sec 1 measured at 345°C in a capillary rheometer using an orifice of 0.015 inch diameter and 1.0" length.
  • the polymer showed a melting point (Tm) of about 355°C.
  • melting point also referred to herein as “melting temperature” is the peak of the endotherm which is devisved by differential scanning calorimetry (DSC) at a heating rate of 20°C/min for the solid to nematic phase transition.
  • DSC differential scanning calorimetry
  • Example 2 illustrates the preparation of a particularly preferred polyester from a 7 mole reaction mixture of 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 4,4'-biphenol, and terephthalic acid in the mole ratio 60.0:4.0:18.0:18.0.
  • the procedure of Example 1 was substantially repeated with the exception that the following components were charged into the flask:
  • the resulting wholly aromatic polymer had an I.V. of about 9 dl/g as determined in hexafluoroisopropanol/pentafluorophenol solution (50/50, v/v) of 0.1% concentration (w/v) at 60°C and a Tm of about 360°C as measured by differential scanning calorimetry.
  • a poly(esteramide) sample made by the method of Example 1 but having an I.V. of about 7 dl/g was made into single filament fibers of about 5 dpf by extruding the molten polymer at a temperature of about 355°C through a single hole with a diameter of 5 mils and a length of 7 mils and winding the fiber onto a bobbin at a take-up rate of about 800 m/min.
  • the tensile properties of the as-spun fibers were measured using ASTM test method D3822-79 with a one inch gauge length and a strain rate of 20%/min. The tensile properties were 8.51 gpd tenacity, 1.49% elongation, 609 gpd modulus.
  • the fiber samples were then subjected to various heat treatment cycles to test the effects of heat treatment on properties.
  • the heat treatment experiments were carried out by placing the fiber samples on metal racks that allowed about six inches of span between the points where the fiber samples were mounted. The samples were mounted with enough slack that they were subjected to no stress other than gravity. The racks were placed into a nitrogen purged oven and heated for varying periods of time. The tensile properties were then measured using the same test method but with a three inch gauge length for comparison with the properties of the as-spun fiber.
  • the results obtained by heat treating the fiber at 270°C are shown in Table 1.
  • the results obtained by heat treating the fiber at 305°C are shown in Table 2.
  • a large series of poly(esteramide) fiber samples were heat treated under varying conditions for purposes of comparing their tensile properties.
  • the poly(esteramide) was again synthesized by the method of Example 1 except that the polymerization was stopped when the polymer had an I.V. of about 7 dl/g.
  • the fiber examples were melt spun and then heat treated using the method described in Examples 3-8.
  • the heat-up time from room temperature to the heat treatment temperature was also varied.
  • the tensile properties of the heat-treated fiber samples were again measured. The data are presented in Table 3.
  • the heat-up time was 30 minutes.
  • the tenacities of the fiber samples in Figure 1 show up as a series of approximately concentric ellipses.
  • the highest tenacity predicted by the computer model is about 32 gpd, which occurs with a heat treatment temperature of about 316° to 332°C for a time of about 3.0 to about 4.8 hours. At times or temperatures outside this range, the tenacity is lower.
  • the modulus which appears as a series of approximately vertical lines is at or above 1000 gpd at times in the range of about 3.0 to 5.4 hours at any temperature shown in the plot (about 290°-335°C) .
  • Heat treatment temperatures should be in the range of about 290°C up to the melting point of the fiber (or the temperature at which the fibers stick together) , preferably in the range of about 300°C up to the melting point of the fiber (or the temperature at which the fibers become sticky) , and most preferably in the range of about 310°C to about 335°C.
  • a polyester sample made by the method of Example 2 was extruded into single filament fibers at a temperature of about 360°C using the same method as in Examples 3-8.
  • the tensile properties of the as-spun fibers were measured using ASTM test method D3822-79 as previously described.
  • the fiber samples were heat treated at 270°C and 305°C for various times using the method described in Examples 3-8.
  • the data for the heat treatment experiments are presented in Tables 4 and 5. It can be seen from the data in the tables that much higher tensile properties are reached at the higher heat treatment temperature and that these properties are reached rapidly at that temperature (within about 4 hours) and then level off.
  • the computer regression analysis showed the same trends as were observed in the poly(esteramide) .
  • the heat-up time had some effect on the tensile properties.
  • the heat treatment time and heat treatment temperature were much more important in determining the fiber tensile properties.
  • a contour plot of the tenacity and modulus as a function of heat treatment time and temperature is shown in Figure 2 (the heat-up time was 30 minutes).
  • the tenacity response surface based on the computer model appears as a series of approximately concentric ellipses, with the highest tenacities (29 gpd) being obtained in about 1.5 to 4.5 hours at about 305°C to about 330°C.
  • the modulus appears to be highest at very short heat treatment times. Heat treatment for about an hour or less at any temperature on the plot (290°- 340°C) results in a modulus of greater than about 950 gpd.
  • This computer-generated plot indicates that high heat treatment temperatures result in excellent fiber tensile properties within relatively short times. It also illustrates that excessive heat treatment results in poorer tensile properties. It appears from the data and the computer-generated plot that a short heat treatment cycle at high temperatures will result in a single filament fiber having a tenacity of at least about 24 gpd, preferably at least about 27 gpd, and most preferably at least about 29 gpd, and a modulus of at least about 750 gpd, preferably at least about 900 gpd, and most preferably at least about 1000 gpd.' The plot and data suggest that the heat treatment time should be in the range of about 0.25 to about 6 hours, preferably in the range of about 0.5 to about 5 hours, and most preferably in the range of about 1.5 to about 4 hours.
  • Heat treatment temperatures should be in the range of about 290°C up to the melting temperature of the fiber (or the temperature at which the fibers become sticky) , preferably in the range of about 300° to about 340°C, and most preferably in the range of about 310°C to about 330°C.
  • a poly(esteramide) sample having the composition of Example 1 was made into a yarn (200 denier/40 filament) by extruding the molten polymer at a temperature of 369°C through a 40 hole x 0.005"diameter x 0.007" length spinneret. The yarn was taken up at a rate of about 2500 fpm. The tensile properties of the as-spun yarns were measured using ASTM test method D885 using a ten inch gauge length, 2.5 twists per inch and a 10% strain rate. The yarn samples were then subjected to various heat treatment cycles to test the effects of heat treatment on yarn properties. The heat treatment experiments were carried out by winding the yarn onto heat-resistant bobbins with low tension.
  • a polyester sample was made into a yarn (200 denier/40 filament) by extruding the molten polymer at a temperature of 364°C through a 40 hole x 0.005" diameter x 0.007" length spinneret. The yarn was taken up at a rate of about 2500 fpm.
  • the tensile properties of the as-spun yarns were measured using ASTM test method D885 using a ten inch gauge length, 2.5 twists per inch and a 10% strain rate.
  • the yarn samples were then subjected to various heat treatment cycles to test the effects of heat treatment on yarn properties.
  • the heat treatment experiments were carried out by winding the yarn onto heat-resistant bobbins with low tension. The bobbins were placed into a nitrogen purged oven and heated. The tensile properties were then measured for comparison with the properties of the as-spun yarn. The results are shown in Table 8.
  • the polyester yarn achieves excellent modulus and tenacity within 4 hours of heat treatment. In this case, the properties neither fall nor increase significantly after 4 hours.
  • the tensile properties of the yarns are somewhat lower than the tensile properties measured for single filament fibers. The difference again may be the result of the use of a different test method for fibers than for yarns.
  • heat treatment of a yarn for abou 0.25 to about 6 hours at a temperature greater than about 290°C yields a yarn having tenacity greater than about 18 gpd and a modulus greater than about 700 gpd.
  • heat treatment of a yarn made from the liquid crystalline polyester for a time in the range of about 0.5 to about 5 hours at a temperature greater than about 300°C yields a yarn having a tenacity greater than about 19 gpd and a modulus greater than about 750 gpd.

Abstract

Il est possible de fabriquer des fibres et fils à haute résistance et haut module. Pour ce faire, il convient de soumettre à un traitement thermique relativement bref à hautes températures des fibres et des fils bruts de filage en polyesters ou poly(amides d'ester) liquides cristallins constitués essentiellement d'unités monomères dérivées d'acide 6-hydroxy-2-naphtoïque, d'acide 4-hydroxybenzoïque, de 4, 4'-biphénol, d'acide téréphtalique et d'un aminophénol ou diamine aromatique facultatif tel le p-aminophénol préféré.
PCT/US1994/000400 1993-03-26 1994-01-12 Traitement thermique rapide de fibres liquides cristallines WO1994022936A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US3780493A 1993-03-26 1993-03-26
US08/037,804 1993-03-26

Publications (1)

Publication Number Publication Date
WO1994022936A1 true WO1994022936A1 (fr) 1994-10-13

Family

ID=21896436

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1994/000400 WO1994022936A1 (fr) 1993-03-26 1994-01-12 Traitement thermique rapide de fibres liquides cristallines

Country Status (1)

Country Link
WO (1) WO1994022936A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0697040B1 (fr) * 1993-05-06 1999-06-02 SINCO RICERCHE S.p.A. Fibres a module d'elasticite eleve preparees a partir de resines polyester
DE10349794A1 (de) * 2003-10-24 2005-05-25 Continental Aktiengesellschaft Fahrradreifen
EP2123807A1 (fr) * 2007-02-28 2009-11-25 Toray Industries, Inc. Fibre de polyester cristal liquide et son procédé de fabrication

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183895A (en) * 1975-04-29 1980-01-15 E. I. Du Pont De Nemours And Company Process for treating anisotropic melt-forming polymeric products
US4325903A (en) * 1980-07-15 1982-04-20 Celanese Corporation Processing of melt processible liquid crystal polymer by control of thermal history
US4332759A (en) * 1980-07-15 1982-06-01 Celanese Corporation Process for extruding liquid crystal polymer
US4473682A (en) * 1982-07-26 1984-09-25 Celanese Corporation Melt processable polyester capable of forming an anisotropic melt comprising a relatively low concentration of 6-oxy-2-naphthoyl moiety, 4-oxybenzoyl moiety, 4,4'-dioxybiphenyl moiety, and terephthaloyl moiety
US4574066A (en) * 1984-02-27 1986-03-04 Celanese Corporation Process for the expeditious formation of a high strength shaped article of poly(6-oxy-2-naphthoate-4-oxybenzoate)
US4983713A (en) * 1988-07-05 1991-01-08 Polyplastics Co., Ltd. Polyester resin exhibiting optical anisotropy in molten state containing minor amounts of 6-oxy-2-naphthoyl units
US5015722A (en) * 1990-04-04 1991-05-14 Hoechst Celanese Corporation Melt-processable polyester capable of forming an anisotropic melt which exhibits a highly attractive balance between its molding and heat deflection temperatures
US5045257A (en) * 1987-10-02 1991-09-03 Kuraray Co., Ltd. Process for producing aromatic polyester fiber
US5049295A (en) * 1988-12-29 1991-09-17 Kawasaki Steel Corporation Aromatic polyester, aromatic polyester amide, filaments thereof and compositions thereof each containing an inorganic filler or magnetic powder

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183895A (en) * 1975-04-29 1980-01-15 E. I. Du Pont De Nemours And Company Process for treating anisotropic melt-forming polymeric products
US4325903A (en) * 1980-07-15 1982-04-20 Celanese Corporation Processing of melt processible liquid crystal polymer by control of thermal history
US4332759A (en) * 1980-07-15 1982-06-01 Celanese Corporation Process for extruding liquid crystal polymer
US4473682A (en) * 1982-07-26 1984-09-25 Celanese Corporation Melt processable polyester capable of forming an anisotropic melt comprising a relatively low concentration of 6-oxy-2-naphthoyl moiety, 4-oxybenzoyl moiety, 4,4'-dioxybiphenyl moiety, and terephthaloyl moiety
US4574066A (en) * 1984-02-27 1986-03-04 Celanese Corporation Process for the expeditious formation of a high strength shaped article of poly(6-oxy-2-naphthoate-4-oxybenzoate)
US5045257A (en) * 1987-10-02 1991-09-03 Kuraray Co., Ltd. Process for producing aromatic polyester fiber
US4983713A (en) * 1988-07-05 1991-01-08 Polyplastics Co., Ltd. Polyester resin exhibiting optical anisotropy in molten state containing minor amounts of 6-oxy-2-naphthoyl units
US5049295A (en) * 1988-12-29 1991-09-17 Kawasaki Steel Corporation Aromatic polyester, aromatic polyester amide, filaments thereof and compositions thereof each containing an inorganic filler or magnetic powder
US5015722A (en) * 1990-04-04 1991-05-14 Hoechst Celanese Corporation Melt-processable polyester capable of forming an anisotropic melt which exhibits a highly attractive balance between its molding and heat deflection temperatures

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0697040B1 (fr) * 1993-05-06 1999-06-02 SINCO RICERCHE S.p.A. Fibres a module d'elasticite eleve preparees a partir de resines polyester
DE10349794A1 (de) * 2003-10-24 2005-05-25 Continental Aktiengesellschaft Fahrradreifen
EP2123807A1 (fr) * 2007-02-28 2009-11-25 Toray Industries, Inc. Fibre de polyester cristal liquide et son procédé de fabrication
EP2123807A4 (fr) * 2007-02-28 2010-10-13 Toray Industries Fibre de polyester cristal liquide et son procédé de fabrication
EP2594668A1 (fr) * 2007-02-28 2013-05-22 Toray Industries, Inc. Fibre de polyester cristallin liquide et son procédé de production

Similar Documents

Publication Publication Date Title
CA1187650A (fr) Polyesters formant une masse fondue, optiquement anisotrope
US4159365A (en) Polyphenyl-1,4-phenylene terephthalates and fibers therefrom
US4412058A (en) Aromatic polyesters and high strength filaments thereof
JPH068348B2 (ja) ポリイミド・エステル
US4188476A (en) Aromatic polyester consisting essentially of p-oxybenzoyl units, terephthaloyl units, 2,6-dioxynaphthalene or 2,6-dioxyanthraquinone units and m-oxybenzoyl or 1,3-dioxyphenylene units
IE50267B1 (en) Aromatic polyester and filaments
JPH01306615A (ja) 全芳香族ポリエステル繊維
CA1168398A (fr) Polyesters formant des produits fondus anisotropes
WO1993002122A1 (fr) Copolyesters pour fibres a module eleve
US4499259A (en) Optically anisotropic melt forming copolyesters
CA1131847A (fr) Polyesters thermotropes de 2,6-dihydroxyanthraquinone
US5945216A (en) Process for making high denier filaments of thermotropic liquid crystalline polymers and compositions thereof
CA1178743A (fr) Polyester aromatique et filaments
WO1994022936A1 (fr) Traitement thermique rapide de fibres liquides cristallines
US4487916A (en) Melt-spinnable copolyesters
CA2280327A1 (fr) Procede de fabrication de fibres multilobees a denier eleve composees de cristaux liquides polymeriques thermotropiques et compositions de ces produits
US4391966A (en) Polymers from phenylterephthalic acid
JPS61236826A (ja) 全芳香族ポリエステルアミドの製法
JPH0645674B2 (ja) 光学的異方性をもつ熔融物を生じるポリエステル共重合体
US5171506A (en) Process for producing polyester fibers
JPH0625255B2 (ja) 全芳香族ポリエステルアミド
JPS61239014A (ja) 高性能繊維の製造方法
IE52941B1 (en) Aromatic polyester and filaments

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase