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
  • D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
  • D01F11/04—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers
  • D01F11/06—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers of macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • 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
  • D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
  • D01F11/10—Chemical after-treatment of artificial filaments or the like during manufacture of carbon
  • D01F11/12—Chemical after-treatment of artificial filaments or the like during manufacture of carbon with inorganic substances ; Intercalation
  • D01F11/124—Boron, borides, boron nitrides
• • 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
  • D01F6/28—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D01F6/30—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising olefins as the major constituent
• • 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
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F10/00—Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• • 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
  • D01F6/02—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D01F6/04—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyolefins
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
  • D06M11/80—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with boron or compounds thereof, e.g. borides
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
  • D06M11/80—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with boron or compounds thereof, e.g. borides
  • D06M11/82—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with boron or compounds thereof, e.g. borides with boron oxides; with boric, meta- or perboric acids or their salts, e.g. with borax
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M2101/00—Chemical constitution of the fibres, threads, yarns, fabrics or fibrous goods made from such materials, to be treated
  • D06M2101/16—Synthetic fibres, other than mineral fibres
  • D06M2101/18—Synthetic fibres consisting of macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D06M2101/20—Polyalkenes, polymers or copolymers of compounds with alkenyl groups bonded to aromatic groups

Definitions

• carbonaceous articles such as carbon fibers
• PAN polyacrylonitrile
• cellulose precursors a fabricated article, such as a fiber or a film
• Precursors may be formed into fabricated articles using standard techniques for forming or molding polymers.
• the fabricated article is subsequently stabilized to allow the fabricated article to substantially retain shape during the subsequent heat-processing steps; without being limited by theory, such stabilization typically involves a combination of oxidation and heat and generally results in dehydrogenation, ring formation, oxidation and crosslinking of the precursor which defines the fabricated article.
• the stabilized fabricated article is then converted into a carbonaceous article by heating the stabilized fabricated article in an inert atmosphere. While the general steps for producing a carbonaceous article are the same for the variety of precursors, the details of those steps vary widely depending on the chemical makeup of the selected precursor.
• Polyolefins have been investigated as an alternative precursor for carbonaceous articles, but a suitable and economically viable preparation process has proven elusive.
• identifying an economical process for preparing carbonaceous articles from polyolefin precursors For example, maximizing mass retention during the stabilization and carbonization steps is of interest.
• the present disclosure describes a method for preparing a boron-treated carbonized article comprising providing a fabricated polyolefin article; crosslinking the fabricated article with a boron-containing species (BCS); stabilizing the fabricated article by air oxidation; and carbonizing the fabricated article.
• the present disclosure further describes preparing a stabilized article.
• numeric ranges for instance “from 2 to 10,” are inclusive of the numbers defining the range (e.g., 2 and 10).
• ratios, percentages, parts, and the like are by weight.
• the crosslinkable functional group content for a polyolefin resin is characterized by the mol % crosslinkable functional groups, which is calculated as the number of mols of crosslinkable functional groups divided by the total number of mols of monomer units contained in the polyolefin.
• “monomer” refers to a molecule which can undergo polymerization, thereby contributing constitutional units to the essential structure of a macromolecule, for example, a polyolefin.
• the present disclosure describes a process for producing a carbonaceous fabricated article from a polyolefin resin. Unless stated otherwise, any method or process steps described herein may be performed in any order.
• Polyolefins are a class of polymers produced from one or more olefin monomer. The polymers described herein may be formed from one or more types of monomers. Polyethylene is the preferred polyolefin resin, but other polyolefin resins may be substituted. For example, a polyolefin produced from ethylene, propylene, or other alpha-olefin (for instance, 1-butene, 1-hexene, 1-octene), or a combination thereof, is also suitable.
• the polyolefins described herein are typically provided in resin form, subdivided into pellets or granules of a convenient size for further melt or solution processing.
• the polyolefin resins described herein are subjected to a crosslinking step.
• the polyolefin resin is crosslinked using a Boron-containing species (BCS).
• the polyolefin resins have been modified to include crosslinkable functional groups which are suitable for reacting in the presence of a BCS to crosslink the polyolefin resin.
• BCS Boron-containing species
• Any BCS suitable for initiating the formation of crosslinks in the polyolefin resin is suitable for use.
• suitable BCSs include borane, borate, borinic acid, boronic acid, boric acid, borinic or boronic ester, boroxine, aminoborane, borazine, borohydrides and derivatives and combinations thereof.
• copolymers are suitable to provide a polyolefin resin having crosslinkable functional groups where one or more alpha-olefins have been copolymerized with another monomer containing a group suitable for serving as a crosslinkable functional group, for example, dienes, carbon monoxide, glycidyl methacrylate, acrylic acid, vinyl acetate, maleic anhydride, or vinyl trimethoxy silane (VTMS) are among the monomers suitable for being copolymerized with the alpha-olefin.
• a group suitable for serving as a crosslinkable functional group for example, dienes, carbon monoxide, glycidyl methacrylate, acrylic acid, vinyl acetate, maleic anhydride, or vinyl trimethoxy silane (VTMS) are among the monomers suitable for being copolymerized with the alpha-olefin.
• VTMS vinyl trimethoxy silane
• polyolefin resin having crosslinkable functional groups may also be produced from a poly(alpha-olefin) which has been modified by grafting a functional group moiety onto the base polyolefin, wherein the functional group is selected based on its ability to subsequently enable crosslinking of the given polyolefin.
• grafting of this type may be carried out by use of free radical initiators (such as peroxides) and vinyl monomers (such as VTMS, dienes, vinyl acetate, acrylic acid, methacrylic acid, acrylic and methacrylic esters such as glycidyl methacrylate and methacryloxypropyl trimethoxysilane, allyl amine, p-aminostyrene, dimethylaminoethyl methacrylate) or via azido-functionalized molecules (such as 4-[2-(trimethoxysilyl)ethyl]benzenesulfonyl azide).
• free radical initiators such as peroxides
• vinyl monomers such as VTMS, dienes, vinyl acetate, acrylic acid, methacrylic acid, acrylic and methacrylic esters such as glycidyl methacrylate and methacryloxypropyl trimethoxysilane, allyl amine, p-aminostyrene, dimethyl
• Polyolefin resins having crosslinkable functional groups may be produced from a polyolefin resin, or may be purchased commercially.
• Examples of commercially available polyolefin resins having crosslinkable functional groups include SI-LINK sold by The Dow Chemical Company, PRIMACOR sold by The Dow Chemical Company, EVAL resins sold by Kuraray, and LOTADER AX8840 sold by Arkema.
• the polyolefin resin is processed to form a fabricated article.
• a fabricated article is an article which has been fabricated from the polyolefin resin.
• the fabricated article is formed using known polyolefin fabrication techniques, for example, melt or solution spinning to form fibers, film extrusion or film casting or a blown film process to form films, die extrusion or injection molding or compression molding to form more complex shapes, or solution casting.
• the fabrication technique is selected according to the desired geometry of the target carbonaceous article, and the desired physical properties of the same. For example, where the desired carbonaceous article is a carbon fiber, fiber spinning is a suitable fabrication technique. As another example, where the desired carbonaceous article is a carbon film, compression molding is a suitable fabrication technique.
• crosslinking is carried out via chemical crosslinking using a BCS. It is anticipated that the crosslinked fabricated article is crosslinked via multiple paths, for example, a portion of the crosslinked fabricated article may be crosslinked using a BCS and another portion of the crosslinked fabricated article may be crosslinked via another crosslinking method known in the art, for example, by use of irradiation or other non-boron containing mechanism.
• the crosslinked fabricated article is a fabricated article which has been treated with one or more boron-containing chemical agents to crosslink the crosslinkable functional groups of the polyolefin resin having crosslinkable functional groups.
• Such chemical agent functions to initiate the formation of intramolecular chemical bonds between the crosslinkable functional groups or reacts with the crosslinkable functional groups to form intramolecular chemical bonds, as is known in the art.
• Chemical crosslinking causes the crosslinkable functional groups to react to form new bonds, forming linkages between the various polymer chains which define the polyolefin resin having crosslinkable functional groups.
• the chemical agent which effectuates the crosslinking is selected based on the type of crosslinkable functional group(s) included in the polyolefin resin; a diverse array of reactions are known which crosslink crosslinkable functional groups via intermolecular and intramolecular chemical bonds.
• a suitable chemical agent is selected which is known to crosslink the crosslinkable functional groups present in the fabricated article to produce the crosslinked fabricated article.
• suitable chemical agents include free radical initiators such as peroxides or azo-bis nitriles, for example, dicumyl peroxide, dibenzoyl peroxide, t-butyl peroctoate, azobisisobutyronitrile, and the like.
• a suitable chemical agent can be a compound containing at least two nucleophilic groups, including dinucleophiles such as diamines, diols, dithiols, for example ethylenediamine, hexamethylenediamine, butane diol, or hexanedithiol.
• dinucleophiles such as diamines, diols, dithiols, for example ethylenediamine, hexamethylenediamine, butane diol, or hexanedithiol.
• Compounds containing more than two nucleophilic groups for example glycerol, sorbitol, or hexamethylene tetramine can also be used.
• Lewis or Bronsted acid or base catalysts include aryl sulfonic acids, sulfuric acid, hydroxides, zirconium alkoxides or tin reagents.
• Crosslinking the fabricated article is generally preferred to ensure that the fabricated article retains its shape at the elevated temperatures required for the subsequent processing steps. Without crosslinking, polyolefin resins typically soften, melt or otherwise deform or breakdown at elevated temperatures. Crosslinking adds thermal stability to the fabricated article.
• the crosslinked fabricated article is heated in an oxidizing environment to yield a stabilized fabricated article.
• the temperature for stabilizing the crosslinked fabricated article is at least 120° C., preferably at least 190° C.
• the temperature for stabilizing the crosslinked fabricated article is no more than 400° C., preferably no more than 300° C.
• the crosslinked fabricated article is introduced to a heating chamber which is already at the desired temperature.
• the fabricated article is introduced to a heating chamber at or near ambient temperature, which chamber is subsequently heated to the desired temperature.
• the heating rate is at least 1° C./minute. In other embodiments the heating rate is no more than 15° C./minute.
• the chamber is heated step wise, for instance, the chamber is heated to a first temperature for a time, such as, 120° C. for one hour, then is raised to a second temperature for a time, such as 180° C. for one hour, and third is raised to a holding temperature, such as 250° C. for 10 hours.
• the stabilization process involves holding the crosslinked fabricated article at the given temperature for periods up to 100 hours depending on the dimensions of the fabricated article.
• the stabilization process yields a boron-treated stabilized fabricated article which is a precursor for a carbonaceous article.
• the stabilization process oxidizes the crosslinked fabricated article and causes changes to the hydrocarbon structure that increases the crosslink density while decreasing the hydrogen/carbon ratio of the crosslinked fabricated article.
• the stabilization process introduces boron to the hydrocarbon structure by treating the fabricated article with boron during the stabilization process.
• the present disclosure describes a boron-treated stabilized fabricated article which is formed from a polyolefin precursor (resin).
• the boron-treated stabilized fabricated article is formed according to the process described herein.
• Carbonaceous articles are articles which are rich in carbon; carbon fibers, carbon sheets and carbon films are examples of carbonaceous articles.
• Carbonaceous articles have many applications, for example, carbon fibers are commonly used to reinforce composite materials, such as in carbon fiber reinforced epoxy composites, while carbon discs or pads are used for high performance braking systems.
• the carbonaceous articles described herein are prepared by carbonizing the stabilized fabricated article by heat-treating the boron-treated stabilized fabricated articles in an inert environment.
• the inert environment is an environment surrounding the boron-treated stabilized fabricated article that shows little reactivity with carbon at elevated temperatures, preferably a high vacuum or an oxygen-depleted atmosphere, more preferably a nitrogen atmosphere or an argon atmosphere. It is understood that trace amounts of oxygen may be present in the inert atmosphere.
• the temperature of the inert environment is at or above 600° C.
• the temperature of the inert environment is at or above 800° C.
• the temperature of the inert environment is no more than 3000° C. In one instance, the temperature is from 1400-2400° C. Temperatures at or near the upper end of that range will produce a graphite article, while temperatures at or near the lower end of the range will produce a carbon article.
• the boron-treated stabilized fabricated article is introduced to a heating chamber containing an inert environment at or near ambient temperature, which chamber is subsequently heated over a period of time to achieve the desired final temperature.
• the heating schedule can also include one or more hold steps for a prescribed period at the final temperature or an intermediate temperature or a programmed cooling rate before the article is removed from the chamber.
• the chamber containing the inert environment is subdivided into multiple zones, each maintained at a desired temperature by an appropriate control device, and the boron-treated stabilized fabricated article is heated in a stepwise fashion by passage from one zone to the next via an appropriate transport mechanism, such as a motorized belt.
• an appropriate transport mechanism such as a motorized belt.
• this transport mechanism can be the application of a traction force to the fiber at the exit of the carbonization process while the tension in the stabilized fiber is controlled at the inlet.
• m PE is the initial mass of polyethylene
• m OX is the mass remaining after oxidation
• m CF is the mass remaining after carbonization
• M % PE is the mass % of polyethylene in the origin formed article.
• Soxhlet extraction is a method for determining the gel content and swell ration of crosslinked ethylene plastics.
• Soxhlet extraction is conducted according to ASTM Standard D2765-11 “Standard Test Methods for Determination of Gel Content and Swell Ratio of Crosslinked Ethylene Plastics.”
• a crosslinked fabricated article between 0.050-0.500 g is weighed and placed into a cellulose-based thimble which is then placed into a Soxhlet extraction apparatus with sufficient quantity of xylenes.
• Soxhlet extraction is then performed with refluxing xylenes for at least 12 hours.
• the thimbles are removed and the crosslinked fabricated article is dried in a vacuum oven at 80° C. for at least 12 hours and then weighed, thereby providing a Soxhlet-treated article.
• the gel content (%) is then calculated from the weight ratio (Soxhlet-treated article)/(crosslinked fabricated article).
• the VTMS-grafted precursor resin is melt spun to form fibers with the following properties: 1573 filaments, 1945.8 total denier, 2.25 gf/den, 12.17% elongation-to-break.
• Fiber tows are continuously treated in a vessel containing an isopropanol solution with 5 wt % of boric acid. Fiber residence time in the solution is 5 seconds. The treated fibers are allowed to dry cure for 3 days. The fibers are subsequently moisture cured at 80° C. (100% relative humidity) for 1-5 days, as reported in Table 1. Gel fraction is determined to be 42.9-55.2% by Soxhlet extraction. Complete results are reported in Table 2.
• the boric acid crosslinked fibers are oxidized and carbonized using a Thermogravimetric Analysis (TGA) instrument using the conditions outlined in Table 3.
• the temperature ramp rates are maintained at 10° C./min for the oxidation and carbonization regimes.
• Table 4 reports the mass retained during air oxidation and final mass yield after both oxidation and carbonization treatments.
• the VTMS-grafted precursor resin is melt spun to form fibers with the following properties: 1573 filaments, 1945.8 total denier, 2.25 gf/den, 12.17% elongation-to-break.
• the fiber tows are continuously treated in a vessel containing an isopropanol solution with 5 wt % of boric acid.
• the fiber residence time in the vessel is 5 minutes.
• the treated fibers are allowed to dry cure for 3 days.
• the fibers are subsequently moisture cured at 80° C. (100% relative humidity) for 1-5 days, as reported in Table 5.
• Gel fraction is determined to be 42.4-54.1% by Soxhlet extraction. Complete results are reported in Table 6.
• the resulting boric acid crosslinked fibers are oxidized and carbonized using a Thermogravimetric Analysis (TGA) instrument using the conditions outlined in Table 7. Temperature ramp rates are maintained at 10° C./min for oxidation and carbonization regimes. Table 8 reports the mass retained during air oxidation and final mass yield after both oxidation and carbonization treatments.
• TGA Thermogravimetric Analysis
• the thermally treated, boric acid treated crosslinked fibers are oxidized and carbonized using a Thermogravimetric Analysis (TGA) instrument using the conditions outlined in Table 11. Temperature ramp rates are maintained at 10° C./min for oxidation and carbonization regimes. Table 12 reports the mass retained during air oxidation and final mass yield after both oxidation and carbonization treatments.
• TGA Thermogravimetric Analysis

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• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Inorganic Chemistry (AREA)
• Inorganic Fibers (AREA)
• Treatments Of Macromolecular Shaped Articles (AREA)
• Carbon And Carbon Compounds (AREA)
• Processes Of Treating Macromolecular Substances (AREA)

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• 2016
  • 2016-04-07 JP JP2017555777A patent/JP2018517852A/ja active Pending
  • 2016-04-07 WO PCT/US2016/026456 patent/WO2016176022A1/en not_active Ceased
  • 2016-04-07 CN CN201680022956.9A patent/CN107532338A/zh active Pending
  • 2016-04-07 EP EP16718571.9A patent/EP3289122A1/en not_active Withdrawn
  • 2016-04-07 US US15/551,957 patent/US20180038017A1/en not_active Abandoned
  • 2016-04-19 TW TW105112184A patent/TW201638003A/zh unknown
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