US3632092A - Stabilization procedure and apparatus for polymeric fibrous materials - Google Patents
Stabilization procedure and apparatus for polymeric fibrous materials Download PDFInfo
- Publication number
- US3632092A US3632092A US865334A US3632092DA US3632092A US 3632092 A US3632092 A US 3632092A US 865334 A US865334 A US 865334A US 3632092D A US3632092D A US 3632092DA US 3632092 A US3632092 A US 3632092A
- Authority
- US
- United States
- Prior art keywords
- roll
- strand
- heat treatment
- porous
- rotatable
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
Images
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
- D01F9/00—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
- D01F9/08—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
- D01F9/12—Carbon filaments; Apparatus specially adapted for the manufacture thereof
- D01F9/14—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
- D01F9/20—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products
- D01F9/21—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D01F9/22—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyacrylonitriles
- D01F9/225—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyacrylonitriles from stabilised polyacrylonitriles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B13/00—Conditioning or physical treatment of the material to be shaped
- B29B13/02—Conditioning or physical treatment of the material to be shaped by heating
- B29B13/023—Half-products, e.g. films, plates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C71/00—After-treatment of articles without altering their shape; Apparatus therefor
- B29C71/02—Thermal after-treatment
-
- 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
- D01D10/00—Physical treatment of artificial filaments or the like during manufacture, i.e. during a continuous production process before the filaments have been collected
- D01D10/02—Heat treatment
-
- 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
- D01D10/00—Physical treatment of artificial filaments or the like during manufacture, i.e. during a continuous production process before the filaments have been collected
- D01D10/04—Supporting filaments or the like during their treatment
- D01D10/0436—Supporting filaments or the like during their treatment while in continuous movement
-
- 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
- D01F9/00—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
- D01F9/08—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
- D01F9/12—Carbon filaments; Apparatus specially adapted for the manufacture thereof
- D01F9/14—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
Definitions
- the resulting stabilized material retains its original fibrous configuration essentially intact, exhibits enhanced thermal stability, and is capable of undergoing carbonization.
- the precursor is an acrylonitrile homopolymer and air having a temperature of at least about 260 is expelled through the surface of the rotating porous roll.
- a process for the stabilization of a strand of polymeric fibrous material capable of undergoing thermal stabilization comprises passing the strand through a heat treatment zone wherein the strand is continuously wound in a plurality of turns and continuously unwound from at least one rotating roll having a porous surface while a gas at an elevated temperature is expelled outwardly through the surface of the porous roll and penetrates the fibrous configuration of the strand wound upon the roll, and continuously withdrawing the resulting stabilized strand of fibrous material from the heat treatment zone which retains its original fibrous configuration essentially intact, exhibits enhanced thermal stability, and is capable of undergoing carbonization.
- An apparatus for the continuous stabilization of a strand of polymeric fibrous material comprises a substantially enclosed heat treatment chamber, means for continuously introducing a strand of fibrous material into the heat treatment chamber, means for continuously withdrawing a strand of fibrous material from the heat treatment chamber, at least one rotatable roll situated within the chamber having a porous surface, drive means capable of rotating the roll, conduit means essentially coextensive with the length of the roll in a communicative relationship to the porous surface of the roll, heating means situated within the rotatable roll, and means for supplying a gas to the conduit means.
- FIG. 1 is a perspective view partially cut away of a preferred apparatus of the present invention showing the positioning of a strand of polymeric fibrous material upon a rotatable tapered driven roll having a porous surface while a gas at an elevated temperature is expelled outwardly through the surface of the porous roll and penetrates the fibrous configuration to the strand of produce stabilization.
- FIG. 2 is a cross section of the tapered porous roll shown in the apparatus of FIG. 1.
- FIG. 3 is a perspective view of a portion of an alternative apparatus arrangement in which the strand undergoing treatment is continuously wound in a plurality of turns and continuously unwound from a rotatable porous roll having an essentially cylindrical configuration as well as upon a rotatable skewed roll in a paired spaced relationship to the porous roll.
- the stabilized materials formed in accordance with the present invention retain the original fibrous configuration of the organic polymeric precursor, possess an enhanced thermal stability, and are capable of undergoing carbonization by heating in a nonoxidizing atmosphere according to procedures known in the art, e.g., heating in a nitrogen atmosphere at l,000 C.
- the stabilized strands formed in the present process may alternatively be used as heat-resistant fibrous insulative materials, or in other applications where a thermally stable fibrous material is required.
- the fibrous materials when derived from an acrylic precursor are nonbuming when subjected to an ordinary match flame and find utility in the formation of flame-resistant fabrics.
- the organic polymeric materials which are treated in accordance with the present invention may be of varied composition. Those precursors which are capable of undergoing thermal stabilization may be selected.
- the organic polymeric precursor may be an acrylic polymer, a cellulosic polymer, a polyamide, a polybenzimidazole, polyvinyl alcohol, etc.
- acrylic polymeric materials are particularly suited for use in the present process.
- suitable cellulosic materials include the natural and regenerated forms of cellulose, e.g., rayon.
- polyamide precursors include the aromatic polyamldes such as nylon 6T which is formed by the condensation of rhexamethylenediamine and terephthalic acid.
- An illustrative example of a suitable polybenzimidazole is poly-2,2-mphenylene-S ,5 '-bibenzimidazole.
- the acrylic polymer selected for use as the precursor may be formed primarily of recurring acrylonitrile units.
- the acrylic polymer should generally contain not less than about 85 mol percent of recurring acrylonitrile units with not more than about l mol percent of a monovinyl compound which is copolymerizable with acrylonitrile such as styrene, methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, vinylidene chloride, vinyl pyridine and the like, or a plurality of such monomers.
- the starting material is selected in accordance with the teachings of US. Ser. No. 749,957, filed Aug. 5, i968, of Dagobert E. Stuetz, which is assigned to the same assignee as the instant invention, and is herein incorporated by reference. More specifically, the copolymer should contain no more than about 5 mol percent of one or more monovinyl comonomers copolymerized with acrylonitrile. In a particularly preferred embodiment of the invention the acrylic polymer is an acrylonitrile homopolymer.
- the strand of polymeric fibrous material which is treated in accordance with the present invention is preferably a continuous rnultifilament yarn which may be formed by conventional techniques. Various threads, ropes, and cables, or continuous lengths of similar fibrous configurations may be selected.
- the strand which serves as the starting material may optionally be provided with a twist which tends to improve its handling characteristics. For instance, a twist of about 0.l to 5 t.p.i., and preferably about 0.3 to 1.0 t.p.i. may be utilized.
- the fibrous material which serves as the starting material optionally may be highly oriented. Such orientation is generally capable of enhancing the tensile properties of the resulting stabilized fibrous material, as well as of any carbon materials derived therefrom.
- An acrylic starting material may be oriented by hot drawing to a relatively high single-filament tensile strength of at least about 4 grams per denier prior to stabilization. For instance, fibrous acrylic starting materials which possess a single-filament tensile strength of about 4 to 9 grams per denier may be selected for use in the process.
- the atmosphere provided in the heat treatment zone may be varied.
- a cellulosic precursor is commonly stabilized in (I) an oxygen-containing atmosphere or in (2) an inert or nonoxidizing atmosphere, such as nitrogen, helium, argon, etc.
- precursors such as an acrylic polymer, a polyamide, a polybenzimidazole, or polyvinyl alcohol are commonly stabilized in an oxygen-containing atmosphere.
- Air may be conveniently selected as the oxygen-containing atmosphere for use in the process.
- the precursor may be preliminarily treated with catalytic agents which are capable of promoting the stabilization reaction.
- the stabilization treatment is conducted in an oxygen-containing atmosphere, it is commonly termed a preoxidation" treatment particularly when followed by carbonization which is conducted in an inert atmosphere.
- the stabilization zone is substantially enclosed in order to facilitate the confinement and withdrawal of off gases and/or the maintenance of an appropriate atmosphere.
- a nonoxidizing atmosphere is desired within the heat treatment chamber the strand may pass through a seal as it continuously enters and leaves the heat treatment chamber in order to ex clude oxygen.
- the stabilization of fibers of acrylonitrile homopolymers and copolymers in an oxygen-containing atmosphere involves (l)an oxidative cross-linking reaction of adjoining molecules as well as (2) a cyclization reaction of pendant nitrile groups to a condensed dihydropyridine structure. While the reaction mechanism is complex and not readily explainable it is believed that these two reactions occur concurrently, or are to some extent competing reactions.
- the cyclization reaction involving pendant nitrile groups which occurs upon exposure of an acrylic fibrous material to heat is generally highly exothermic and, if uncontrolled, results in the destruction of the fibrous configuration of the starting material. ln some instances this exothermic reaction will occur with explosive violence and result in the fibrous material being consumed by flame. More commonly, however, the fibrous material will simply rupture, disintegrate and/or coalesce when the critical temperature is reached. As the quantity of comonomer present in an acrylonitrile copolymer is increased, a fibrous material consisting of the same tends to soften at a progressively lower temperature and the possible destruction of the original fibrous configuration through coalescence of adjoining fibers becomes a factor of increasing importance.
- the critical temperature referred to herein is defined as the temperature at which the fibrous configuration of a given sample of acrylic fibrous starting material will be destroyed in the absence of prior stabilization.
- the acrylic starting material exhibits a critical temperature of at least about 300 C., e.g., about 300 C. to 330 C.
- the detection of the critical temperature of a given acrylic fibrous material may be aided by the use of thermoanalytical methods, such as differential scanning calorimeter techniques, whereby the location and magnitude of the exothermic reaction can be measured quantitatively.
- the strand of polymer fibrous material is continuously wound a plurality of turns in a single strand thickness and continuously unwound from at least one cantilevered rotating roll having a porous surface while a gas at an elevated temperature is expelled outwardly through the surface of the porous roll and penetrates the fibrous configuration of the strand wound upon the roll.
- the roll or rolls are preferably positioned within an essentially enclosed heat treatment chamber or zone whereby stabilization off gases may be confined and withdrawn and/or the appropriate atmosphere maintained.
- the porous roll may be in the configuration of (l) a truncated cone [see FIGS. 1 and 2] or (2) it may by cylindrical having an essentially uniform diameter ⁇ see FIG. 3].
- the strand is passed onto the rotating roll surface at one end and is wound around the roll in a plurality of turns prior to leaving the porous roll surface at the other end.
- a strand of substantial length may be continuously stabilized within a relatively small area.
- the strand is wound about the periphery of the roll in such a manner that it is in intimate contact with the rotating porous surface of the roll and moves along the rotating roll in a helical or spiral path.
- a heated gas is continuously expelled through the surface of the porous roll which effectively penetrates the fibrous configuration of the strand.
- a plurality of porous conical or tapered rolls may be provided within the heat treatment zone.
- the rolls may be intergeared for actuation in unison according to known techniques.
- the strand may accordingly pass from the narrow end of one rotating roll to the wide end of an adjacent rotating roll where the stabilization is continued.
- the gas may be expelled from the surfaces of a series of rolls at successfully elevated temperatures.
- At least one cylindrical porous rotatable driven roll 1 is provided in a paired relationship to a rotatable skewed roll 2, ie an inclined roll, as illustrated in H6. 3.
- a rotatable skewed roll 2 ie an inclined roll, as illustrated in H6.
- tapered roll pairs may be utilized with the taper of each roll being in the same ratio within a given pair.
- the resulting pair of rolls may be positioned in the same or a different plane.
- the pair of rolls is aligned so that when rotated a fibrous strand wound or looped about the same will track from one end of the porous roll to the other while retaining a thickness of a single strand.
- the porous roll is of a substantially larger diameter than the skewed roll.
- the skewed roll optionally may be driven and provided with a porous surface through which a gas at an elevated temperature is also expelled. If not driven the skewed roll may idle, i.e. be rotated by the movement of the fibrous strand wound thereon.
- the rolls are preferably provided in a single plane and aligned so that their axes converge slightly. As will be apparent to those skilled in the fiber art, the strand will track the length of the heated roll and move towards the end where the axes converge. The lesser the degree of convergence the lesser the rate of the lateral movement of the strand along the length of the heated roll.
- the strand is passed to each roll at an angle essentially perpendicular thereto.
- the strand tends to leave each roll for passage to the roll paired therewith at an angle other than 90.
- the strand may be introduced into the heat treatment zone for a plurality of passes in the event the size of the heat treatment chamber is inadequate to complete stabilization during a single pass.
- the strand is treated while in contact with one or more rotating roll having a porous surface while a gas at an elevated temperature is expelled outwardly through the surface of the porous roll and penetrates the fibrous configuration of the strand wound upon the roll as described at least until the strand attains a stabilized form which retains it original fibrous configuration essentially intact.
- the resulting stabilized strand is commonly black in appearance.
- the treatment times during which the strand contacts a porous roll and temperatures will vary depending upon the composition and the exact configuration of the strand of polymeric fibrous material. Temperatures are selected which may be withstood by the strand without the destruction of its original fibrous configuration, e.g., through softening, melting, an uncontrolled exothermic reaction, or decomposition.
- the stabilization treatment may commonly be conducted at about 200 to 320 C. for a porous roll contact time of about 5 to 180 minutes.
- the stabilization treatment may commonly be conducted at about 200 to 350 C. for a porous roll contact time of about 5 to 120 minutes.
- the stabilization treatment may commonly be conducted at about 400 to 550 C. for a porous roll contact time of about 2 to 30 minutes.
- the stabilization treatment may commonly be conducted at about 180 to 200 C. for a porous roll contact time of several hours. More highly elevated temperatures may optionally be utilized during the final portion of the stabilization treatment.
- the stabilization temperature is preferably selected in accordance with the teachings of commonly assigned U.S. Ser. No. 749,957 of Dagobert E. Stuetz which is herein incorporated by reference. With such starting materials the gas expelled through the surface of the porous roll may be provided at a temperature of about 260 C. up to about 10 C. below the critical temperature of the starting material.
- the entire stabilization treatment may be conducted by heating the fibrous material at a temperature substantially within the above range.
- a strand of an acrylonitrile homopolymer fibrous material is heated at about 260 C. to about 300 C. and at a temperature of about 270 C. to 290 C. in a particularly preferred embodiment of the invention.
- the stabilization treatment of the present process may be expedited if the gas is expelled through the surface of one or more porous roll over which the strand passes at successively elevated temperatures as the strand travels through the heat treatment chamber.
- the gas which penetrates the surface of a given porous rotating roll may be supplied to the roll surface at successively elevated temperatures along the length of the roll.
- a plurality of porous rolls may be provided in series with each successive roll expelling a gas through its surface at a more highly elevated temperature than the previous roll over which the strand passed.
- the gas may be initially expelled at a temperature slightly below 260 C. and subsequently increased to at least about 260 C. where a substantial portion of the stabilization reaction occurs.
- the critical temperature exhibited by the unmodified starting material may commonly be exceeded.
- the present continuous process optionally may be conducted on a multiple stage basis in accordance with the teaching of U.S. Ser. No. 749,959 of Michael J. Ram, filed Aug. 5,1968, now U.S. Pat. No. 3,539,295, which is assigned to the same assignee as the instant invention, and is herein incorporated by reference.
- a strand of acrylic fibrous material is subjected to the stabilization treatment for a residence time sufficient to impart a bound oxygen content of at least about 7 percent by weight.
- Higher bound oxygen contents e.g., up to 15 percent or more, may be achieved upon the extended treatment.
- the weight percentage of bound oxygen present in the material may be determined by routine analytical techniques, such as the Unterzaucher analysis.
- stabilization residence times may commonly range from about 10 minutes to about minutes. More extended residence times (e.g. up to 24 hours) are commonly required when utilizing acrylonitrile copolymers containing a higher percentage of comonomer and stabilization temperatures substantially below 260 C., e. g., 200 C.
- shrinkage or stretching of the strand optionally may be carried out depending upon whether the strand initially contacts the porous-tapered roll at its wide end or its narrow end respectively, and whether the particular strand has a propensity to shrink or to stretch at the temperature of the gas being expelled.
- the gas expelled through the surface of the porous roll when conducting the present process may be raised to the desired elevated temperature by any convenient means.
- the gas passes over one or more electric-resistance heating units positioned within the interior of each porous roll.
- the strand of stabilized fibrous material produced in the present process may optionally next be carbonized or carbonized and graphitized at more highly elevated temperatures in a nonoxidizing or inert atmosphere, according to techniques known in the art.
- a nonoxidizing or inert atmosphere e.g., nitrogen, hydrogen and oxygen.
- carbonized as used herein is defined to describe a product consisting of at least about 90 percent carbon by weight. Suitable atmospheres include nitrogen, argon, helium, etc.
- a particularly preferred carbonization or carbonization and graphitization process is disclosed in commonly assigned U.S. Ser. No. 777,275, filed Nov. 28, 1968 of Charles M. Clarke which is herein incorporated by reference.
- EXAMPLE I An acrylonitrile homopolymer is dry spun to produce a 40 fil continuous yarn, and is hot drawn at a draw ratio of about 7.5:] to obtain a highly oriented fibrous material having a single filament tenacity of about 7 grams per denier. Twenty ends of this yarn are then plied to produce the 800 fil strand having a total denier of about 1,150 which is utilized as the starting material.
- the strand of acrylic fibrous material may be provided on a bobbin 4 located outside the substantially enclosed treatment chamber 6 having walls 8.
- a cantilevered rotatable roll 10 having the configuration of a truncated cone and a porous surface.
- the wide end 12 of the roll has a diameter inches, and the narrow end 14 of the roll has a diameter of 4.5 inches.
- the length of the roll is 24 inches.
- the rotatable roll 10 is mounted upon a hollow conductive shaft 16 which extends through a seal in the wall of the heat treatment chamber 6, and is driven by the aid of pinion l8 and worm gear 20.
- the hollow conductive shaft is bolted to supporting member 21 with the aid of fixed end plate 22 and is rendered rotatable by bearing 24.
- Air is continuously supplied at an adjustable overpressure to the end 28 of the hollow conductive shaft 16 which extends through supporting member 21 by a fan (not shown).
- a multilead cable 30 extends into hollow shaft 16 and supplies electrical current to resistance heaters (not shown) situated within rotatable roll 10. Air introduced into hollow shaft 16 at end 28 passes over resistance heaters and is continuously expelled outwardly through the porous surface 32 of rotatable roll 10.
- the hollow conductive shaft of conduit 16 is coextensive with the length of rotatable roll 10 and further extends through seal 34 in the opposite wall of the heat treatment chamber 6 where it is capped.
- Such extension of hollow conductive shaft 16 through the wall of the chamber lends additional support to the rotatable roll 10.
- Nonconductive end plates 36 and 38 are situated at the wide and narrow ends respectively of rotatable roll 10.
- Additional dividers 40, 42, 44 and 46 of a nonconductive material are positioned around the circumference of central conduit 16 and define a series of heating modules 48, 50, S2, and 56 within the interior of rotatable roll 10.
- the porous surface 32 of roll 10 is formed of a sintered ceramic material through which air may be readily expelled outwardly.
- conductive screens 58, 60, 62, 64, and 66 which are welded to pairs of conductive rings 68, 70, 72, 74, and 76.
- One member of each pair of conductive rings is welded to hollow conductive shaft 16.
- Multilead cable 30 includes a series of five individual leads 78, 80, 82, 84, and 86 which pass through oversized openings in hollow conductive shaft 16 lined with insulative bushings 88, 90, 92, 94, and 96.
- the individual power leads 78, 80, 82, 84, and 86 are welded to one member of each pair of conductive rings 68, 70, 72, 74, and 76 respectively. Electric current is supplied to each individual power lead 78, 80, 82, 84, and 86 from a variable power source 98 with a sliding connector or wiper arrangement 100 of the concentric ring type.
- the strand of acrylic fibrous material As the strand of acrylic fibrous material is unwound from bobbin 4 at a rate of 2 meters/minute, it passes through an opening in the wall 8 of the heat treatment chamber 6 and meets the porous surface 32 of rotating roll 10 at its wide end 12.
- the strand winds 11 turns per inch along the axial length of rotating roll 10 in the absence of strand overlap.
- Electric current is supplied to individual leads 78, 80, 82, 84, and 86 so that conductive screens 56, 60, 62, 64, and 6S impart a uniform temperature of 270 C. to the air which is expelled outwardly through the porous surface 32 of roll 10.
- Such air penetrates the fibrous configuration of the strand wound upon roll 10 and stabilizes the same.
- the contact time of the strand upon roll 10 is 50 minutes. As shown in FIG. 1 the resulting stabilized strand is continuously unwound from the narrow end 14 of rotating roll 10 and withdrawn from heat treatment chamber 6 through opening 102 and wound upon bobbin 104.
- gases from the stabilization treatment are removed from heat treatment chamber 10 through exhaust duct 106, with the aid of fan 108. If desired, gases removed from duct 106 may be scrubbed and at least partially recycled to the end 28 of hollow conductive shaft 16.
- the resulting stabilized strand present upon bobbin 104 is black in appearance, exhibits a bound oxygen content of 8 percent by weight as determined by the Unterzaucher analysis, retains its original fibrous configuration essentially intact, and is nonburning when subjected to an ordinary match flame.
- the stabilized strand may be woven to form a fire-resistant fabric, or carbonized or carbonized and graphitized in an inert atmosphere in accordance with the teachings of US. Ser. No. 777,275, filed Nov. 20, 1968 which is herein incorporated by reference.
- the carbonized or carbonized and graphitized fibrous products find particular utility as a reinforcing medium when suspended in a suitable matrix material to form an article useful as a strong lightweight structural component.
- EXAMPLE ll Example 1 is repeated with the exception that the air expelled outwardly through the porous surface 32 of roll 10 at heating modules 48, 50, S2, 54, and 56 is at 260 C., 275 C., 310 C., and 350 C. respectively.
- the fibrous strand penetrated by the heated air is passed continuously over each module for a residence time of approximately 5 minutes. Substantially similar results are achieved.
- EXAMPLE III The stabilization procedure of example 1 is repeated with the exception that the strand of starting material is a 740 fil rayon continuous filament yarn having a total denier of about 2,200, the air expelled outwardly through the surface 32 of roll 10 is maintained at a uniform temperature of 220 C., and the strand is penetrated by the heated air while passing along the roll for a residence time of 60 minutes.
- the strand of starting material is a 740 fil rayon continuous filament yarn having a total denier of about 2,200
- the air expelled outwardly through the surface 32 of roll 10 is maintained at a uniform temperature of 220 C., and the strand is penetrated by the heated air while passing along the roll for a residence time of 60 minutes.
- the resulting strand retains its original fibrous configuration essentially intact, exhibits enhanced thermal stability, and is capable of undergoing carbonization.
- EXAMPLE IV The stabilization procedure of example I is repeated with the exception that the strand of starting material is a 300 fil continuous filament yarn of nylon 6T (condensation product of hexamethylenediamine and terephthalic acid) having total denier of about 900, the air expelled outwardly through the surface 32 of roll 10 is maintained at a uniform temperature of 3l5 C., and the strand is penetrated by the heated air while passing along the roll for a residence time of minutes.
- nylon 6T condensation product of hexamethylenediamine and terephthalic acid
- the resulting stabilized strand retains its original fibrous configuration essentially intact, exhibits enhanced thermal stability, and is capable of undergoing carbonization.
- EXAMPLE V The stabilization procedure of example I is repeated with the exception that the strand of starting material is a 400 fil continuous filament yarn of poly-2,2'-m-5 ,5-bibenzimidazole (a preparation of which is described in example ll of US. Pat. No. 3,174,497) having a total denier of about 1,600 the air expelled outwardly through the surface 32 of roll 10 is maintained at a uniform temperature of 470 C., and the strand is penetrated by he heated air while passing along the roll for a resident time of minutes.
- the strand of starting material is a 400 fil continuous filament yarn of poly-2,2'-m-5 ,5-bibenzimidazole (a preparation of which is described in example ll of US. Pat. No. 3,174,497) having a total denier of about 1,600 the air expelled outwardly through the surface 32 of roll 10 is maintained at a uniform temperature of 470 C., and the strand is penetrated by he heated air while passing along the roll for a resident time of
- the resulting stabilized strand is nonburning when subjected to an ordinary match flame and retains its original fibrous configuration essentially intact.
- An apparatus for the continuous stabilization of a strand of polymeric fibrous material comprising a substantially enclosed heat treatment chamber, means for continuously introducing a strand of fibrous material into said heat treatment chamber, means for continuously withdrawing a strand of fibrous material from said heat treatment chamber, at least one rotatable roll situated within said chamber having a porous surface, drive means capable or rotating said roll, conduit means essentially coextensive with the length of said roll in a communicative relationship to said porous surface of said roll, heating means situated within said rotatable roll, and means for supplying a gas to said conduit means.
- Apparatus according to claim 1 wherein said rotatable roll having a porous surface has an essentially uniform cylindrical configuration, and said apparatus is additionally provided with a rotatable skewed roll in a paired relationship to said rotatable roll.
- An apparatus according to claim 1 wherein means are provided for supplying said gas at successively elevated temperatures along said rotatable roll.
- An apparatus for the continuous stabilization of a strand of polymeric fibrous material comprising a substantially enclosed heat treatment chamber, means for continuously introducing a strand of fibrous material into said heat treatment chamber, means for continuously withdrawing a strand of fibrous material from said heat treatment chamber, at least one rotatable roll situated within said chamber having a porous surface, drive means capable of rotating said roll, central conduit means essentially coextensive with the length of said roll, dividing means positioned about the circumference of said central conduit means capable of dividing means capable of dividing the interior of said roll into a plurality of modules which communicate with the porous surface of said roll and said central conduit means, resistance heating means situated within said modules, means for supplying current to said resistance heating means, and means for supplying cur rent to said resistance heating means, and means for supplying a gas to said central conduit means.
- exhaust means are provided to withdraw off gasses generated within said heat treatment chamber.
Abstract
Description
Claims (10)
- 2. An apparatus according to claim 1 wherein said rotatable roll having a porous surface has a tapered configuration.
- 3. Apparatus according to claim 1 wherein said rotatable roll having a porous surface has an essentially uniform cylindrical configuration, and said apparatus is additionally provided with a rotatable skewed roll in a paired relationship to said rotatable roll.
- 4. An apparatus according to claim 1 wherein means are provided for supplying said gas at successively elevated temperatures along said rotatable roll.
- 5. An apparatus for the continuous stabilization of a strand of polymeric fibrous material comprising a substantially enclosed heat treatment chamber, means for continuously introducing a strand of fibrous material into said heat treatment chamber, means for continuously withdrawing a strand of fibrous material from said heat treatment chamber, at least one rotatable roll situated within said chamber having a porous surface, drive means capable of rotating said roll, central conduit means essentially coextensive with the length of said roll, dividing means positioned about the circumference of said central conduit means capable of dividing means capable of dividing the interior of said roll into a plurality of modules which communicate with the porous surface of said roll and said central conduit means, resistance heating means situated within said modules, means for supplying current to said resistance heating means, and means for supplying current to said resistance heating means, and means for supplying a gas to said central conduit means.
- 6. An apparatus according to claim 5 wherein said rotatable roll having a porous surface has a tapered configuration.
- 7. An apparatus according to claim 5 wherein said rotatable roll having a porous surface has an essentially uniform cylindrical configuration, and said apparatus is additionally provided with a rotatable skewed roll in a paired relationship to said rotatable roll having a porous surface,
- 8. An apparatus according to claim 5 wherein said means for continuously introducing a strand of fibrous material into said heat treatment chamber is a bobbin.
- 9. An apparatus according to claim 5 wherein said means for continuously withdrawing a strand of fibrous material from said heat treatment zone is a bobbin.
- 10. An apparatus according to claim 5 wherein exhaust means are provided to withdraw off gasses generated within said heat treatment chamber.
- 11. An apparatus according to claim 5 wherein said means for supplying a gas to said central conduit means is a fan.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US86533469A | 1969-10-10 | 1969-10-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3632092A true US3632092A (en) | 1972-01-04 |
Family
ID=25345272
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US865334A Expired - Lifetime US3632092A (en) | 1969-10-10 | 1969-10-10 | Stabilization procedure and apparatus for polymeric fibrous materials |
Country Status (1)
Country | Link |
---|---|
US (1) | US3632092A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3857673A (en) * | 1974-03-08 | 1974-12-31 | E Andrus | Apparatus for heat treating continuous wire and rod |
US20090038176A1 (en) * | 2005-04-13 | 2009-02-12 | Alfred Dotzler | Multistage continuous dryer, especially for plate-shaped products |
CN112126993A (en) * | 2020-09-16 | 2020-12-25 | 杭州成江纺织有限公司 | Polyester filament yarn preparation process and equipment thereof |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2701765A (en) * | 1951-06-18 | 1955-02-08 | Haloid Co | Xerographic fusing apparatus |
US3161484A (en) * | 1960-11-16 | 1964-12-15 | Du Pont | Temperature control system for heat treatment of running yarn lines |
US3387833A (en) * | 1966-09-02 | 1968-06-11 | Tmm Research Ltd | Heat treatment of filaments |
-
1969
- 1969-10-10 US US865334A patent/US3632092A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2701765A (en) * | 1951-06-18 | 1955-02-08 | Haloid Co | Xerographic fusing apparatus |
US3161484A (en) * | 1960-11-16 | 1964-12-15 | Du Pont | Temperature control system for heat treatment of running yarn lines |
US3387833A (en) * | 1966-09-02 | 1968-06-11 | Tmm Research Ltd | Heat treatment of filaments |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3857673A (en) * | 1974-03-08 | 1974-12-31 | E Andrus | Apparatus for heat treating continuous wire and rod |
US20090038176A1 (en) * | 2005-04-13 | 2009-02-12 | Alfred Dotzler | Multistage continuous dryer, especially for plate-shaped products |
CN112126993A (en) * | 2020-09-16 | 2020-12-25 | 杭州成江纺织有限公司 | Polyester filament yarn preparation process and equipment thereof |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3539295A (en) | Thermal stabilization and carbonization of acrylic fibrous materials | |
US3997638A (en) | Production of metal ion containing carbon fibers useful in electron shielding applications | |
US4069297A (en) | Process for producing carbon fibers | |
US3427120A (en) | Producing method of carbon or carbonaceous material | |
US3392216A (en) | Method for producing carbon structures from molten baked substances | |
US4073869A (en) | Internal chemical modification of carbon fibers to yield a product of reduced electrical conductivity | |
US3961888A (en) | Acrylic fiber conversion utilizing a stabilization treatment conducted initially in an essentially inert atmosphere | |
US3775520A (en) | Carbonization/graphitization of poly-acrylonitrile fibers containing residual spinning solvent | |
US3723607A (en) | Surface modification of carbon fibers | |
US3656904A (en) | Graphitization process | |
US3841079A (en) | Carbon filaments capable of substantial crack diversion during fracture | |
US3677705A (en) | Process for the carbonization of a stabilized acrylic fibrous material | |
US3647770A (en) | Process for formation of a cyclized acrylic fibrous material | |
US3632092A (en) | Stabilization procedure and apparatus for polymeric fibrous materials | |
US3449077A (en) | Direct production of graphite fibers | |
EP0125905B1 (en) | Process for the stabilisation of acrylic fibres | |
US3592595A (en) | Stabilization and carbonization of acrylic fibrous material | |
EP0057492B1 (en) | Process for the surface modification of carbon fibres | |
US3754957A (en) | Enhancement of the surface characteristics of carbon fibers | |
US3826611A (en) | Continuous treatment of a polyacrylonitrile at elevated temperatures on a porous roll | |
US3656910A (en) | Induction furnace having improved susceptor for use in the continuous production of carbonaceous fibrous materials | |
US3723150A (en) | Surface modification of carbon fibers | |
US3914960A (en) | Apparatus for continuously producing preoxidized textile products | |
US3723605A (en) | Process for the production of a continuous length of graphitic fibrous material | |
US3954950A (en) | Production of high tenacity graphitic fibrous materials |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: CCF, INC., Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CELANESE CORPORATION;REEL/FRAME:004413/0650 Effective date: 19850510 |
|
AS | Assignment |
Owner name: BASF STRUCTURAL MATERIALS, INC., 1501 STEELE CREEK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:INMONT CORPORATION, A CORP. OF DE.;REEL/FRAME:004540/0948 Effective date: 19851231 |
|
AS | Assignment |
Owner name: INMONT CORPORATION Free format text: MERGER;ASSIGNORS:NARMCO MATERIALS, INC.;QUANTUM, INCORPORATED;CCF, INC.;REEL/FRAME:004580/0870 Effective date: 19860417 |
|
AS | Assignment |
Owner name: SUBJECT TO AGREEMENT RECITED SEE DOCUMENT FOR DETA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BASF STRUCTURAL MATERIALS INC.;REEL/FRAME:004718/0001 Effective date: 19860108 Owner name: BASF AKTIENGESELLSCHAFT, D-6700 LUDWIGSHAFEN, GERM Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BASF STRUCTURAL MATERIALS INC.;REEL/FRAME:004718/0001 Effective date: 19860108 |