Glassy carbon compositions, multilayer laminates and 3D printed articles

Abstract

Micromorphologically crack-free glassy carbon articles and multilayer laminates of micromorphologically crack-free glassy carbon, each having a length and width of at least 10 mm and a thickness of at least 5 mm, and corresponding methods and apparatus for producing the same are described. 3D-printed glassy carbon articles and 3D-printing apparatus and methods for producing the same are also described. A method for forming glassy carbon containing glassy carbon nanolattice articles as fillers therein is also described. The glassy carbon compositions, articles, and laminates of the present disclosure overcome the thickness limitations of conventional glassy carbon production methods and the microcracking problems associated with conventional attempts to produce glassy carbon of substantial size and thickness.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS The benefit under 35 U.S.C. § 119 of U.S. Provisional Patent Application No. 63 / 019,155, filed May 1, 2020, in the names of Richard Ludington, Luis Eduardo Marin, and Steven John Hultquist, for VITREOUS CARBON COMPOSITIONS, MULTI-LAYER LAMINATES, AND 3-D PRINTED ARTICLES, is hereby claimed. The disclosure of U.S. Provisional Patent Application No. 63 / 019,155 is incorporated herein by reference in its entirety for all purposes.

[0002] Field

[0002] This disclosure generally relates to glassy carbon compositions, multilayer laminates, and 3D printed articles, as well as methods for making and using the same. In various specific aspects, this disclosure relates to micromorphologically crack-free multilayer glassy carbon laminates and methods for making the same, such as glassy carbon laminate articles having a length and width, each of at least 10 mm, and a thickness of at least 5 mm, preferably at least 7 mm. In other aspects, this disclosure relates to glassy carbon 3D printed articles in which channels are formed in the printing process. In yet other aspects, this disclosure relates to glassy carbon compositions containing three-dimensional nanolattices dispersed therein. [Background technology]

[0003]

[0003] U.S. Patent No. 5,182,166 to Burton et al. describes a wear-resistant composite structure comprising glassy carbon in a continuous phase and spirally wound reinforcing fibers interspersed throughout the glassy carbon in a discontinuous phase. In this patent, the inventors describe the tendency of fiber-containing glassy carbon materials to crack during formation, and state that solving this cracking problem involves the use of spirally wound fibers (e.g., in the form of a mesh or wool, having a radius of curvature to diameter ratio in the range of about 5:1 to about 20:1, and comprising 5% to 75% by weight (5% to 30% by volume) of the final composite), which allows for the production of a grain-boundary-free, non-granular, monolithic glassy carbon material having dimensions of at least 100 mm in each of the x, y, and z dimensions.

[0004]

[0004] The '166 patent to Burton et al. describes the time-temperature relationship in the production of glassy carbon materials as involving curing of the resin for approximately 100 hours with a slow temperature increase to 300°-400°, followed by polymerization which may require time increases of 60-600 hours based on the disclosed temperatures, followed by annealing / stabilization for 10-24 hours.

[0005]

[0005] U.S. Patent No. 6,506,482 to Burton et al. describes a reinforced glassy carbon composite in the form of a bulk composite having dimensions greater than 25 millimeters in each of the x, y, and z directions that is isotropic, uniform, essentially completely void-free, and essentially free of signs of bubbles and fumes. The patent also discloses a multilayer laminate material including at least one layer of a glassy carbon composite comprising a discontinuous phase of metal fibers in a continuous phase of pyrolyzed poly(furfuryl alcohol) glassy carbon. These patents teach the formation of glassy carbon composites by placing a metal fiber matrix in a mold cavity, the metal fiber matrix defining a three-dimensional structure having a void therein, compressing the three-dimensional structure within the mold so that the structure laterally conforms to the wall structure of the mold cavity while maintaining the void therein, and partially polymerizing, outside the mold cavity, a continuous phase precursor material comprising (i) poly(furfuryl alcohol) monomers and / or oligomers and (ii) a polymerization catalyst to generate heat of polymerization and undergo an exothermic polymerization reaction. Next, after removing at least a portion of the heat of polymerization, the partially polymerized precursor material is introduced into the mold cavity; under polymerization conditions, the partially polymerized precursor material is solidified in the mold cavity while being compressed with the three-dimensional structure to form a metal-reinforced polymer composite; and subjecting the metal-reinforced polymer composite to pyrolysis conditions effective to pyrolyze the polymer in the composite, resulting in a metal-reinforced glassy carbon composite. These pyrolysis conditions are said to be set forth in the Burton et al. '166 patent.

[0006] No. 7,862,897 to Whitmarsh describes a two-phase nanoporous glassy carbon material having a cementitious morphology characterized by the presence of non-circular pores and excellent hardness and tribological properties useful for high-wear applications. The two-phase nanoporous glassy carbon material is produced by firing particulate vitreous carbon in a composition containing (i) a curable and pyrolyzable precursor resin to form glassy carbon, and, optionally, (ii) one or more additions of a solid lubricant, such as graphite, boron nitride, or molybdenum disulfide; a high-temperature fibrous reinforcement, such as copper, bronze, iron alloy, graphite, alumina, silica, or silicon carbide; or one or more substances to improve electrical conductivity, such as dendritic copper powder, copper “felt,” or graphite flakes, under an inert atmosphere to produce a superior glassy carbon useful, either alone or as a continuous phase in reinforced composites, relative to conventional glassy carbon materials.

[0007] Whitmarsh's '897 patent discloses the production of glassy carbon having a porosity of approximately 13.8%. At column 9, line 21, through column 10, line 3, Whitmarsh describes a method for producing a glassy carbon body of a predetermined size, wherein a plurality of glassy carbon precursor articles of a size smaller than the predetermined size are formed, each such precursor article being formed from a cured precursor resin, the plurality of cured glassy carbon precursor articles being bonded together to form an aggregate using a binding medium comprising the precursor resin and a catalyst, and then pyrolyzing the aggregate containing the cured binding medium to obtain a glassy carbon body of the predetermined size that is two-phase nanoporous glassy carbon. The binding medium may include particulate vitreous carbon dispersed in the precursor resin, such that changes in the binding medium during pyrolysis correspond to changes that occur during such pyrolysis in the cured precursor articles used as components of the aggregate.

[0008] While the Burton et al. '166 and '482 patents describe large (x, y, z) glassy carbon products having thicknesses exceeding 25 mm or even exceeding 100 mm, in column 4, lines 27-34, Whitmarsh states that while glassy carbon has excellent tribological properties, pure glassy carbon is limited to a maximum thickness of about 0.2 inches, and that this limitation can be overcome by incorporating a copper fiber matrix into the glassy carbon matrix, but results in glassy carbon that exhibits an inadequate level of cracking in the final product. Correspondingly, Whitmarsh offers a two-phase material in the '897 patent as a solution to such thickness limitations, but the porosity of this two-phase material is found to be significant and the microcracks present in its micromorphology, thereby adversely affecting the strength and structural integrity of the material.

[0009]

[0009] U.S. Patent No. 8,052,903 to Whitmarsh describes a defect-free glassy carbon material having a three-dimensional (x, y, z) size of greater than 12 millimeters in each of the x, y, and z dimensions. One method for producing such glassy carbon material uses a three-dimensional fiber mesh that is evaporated at high temperatures, impregnated with a polymerizable resin, and then cured. During the initial stages of pyrolysis, the mesh evaporates, forming a residual network of channels in the cured resin mass, which allows gases to escape during the subsequent pyrolysis of the cured resin material to form the glassy carbon product. As a result, it is said that large, defect-free glassy carbon materials suitable for use in structural composites and manufactured articles, such as seals, brake linings, electric motor brushes, and support members, can be formed.

[0010]

[0010] In column 1, lines 12-27, Whitmarsh's '903 patent states that all currently known methods of producing glassy carbon are severely limited in the size of the defect-free glassy carbon material produced thereby, and that while the length and width dimensions can be virtually any size, the thickness is effectively limited to about 10 mm or less for pure, defect-free glassy carbon material, and that thicknesses exceeding such values ​​will result in cracks, holes, chips (scaling), or will produce material with morphological defects that make it unsuitable for commercial use.

[0011] At column 1, lines 47-50, the Whitmarsh '903 patent, in addressing various problems associated with the method of the Burton et al. patent, notes that "during the extended pyrolytic vitrification process, metal reinforcing elements may form metal carbides that are brittle and substantially reduce the strength and structural integrity of the composite material." However, the technique of the Whitmarsh '903 patent, which uses a pyrolytic temporary mesh to form a network of tubular voids that allow gases to escape during the pyrolysis operation, increases the void volume and porosity of the vitreous carbon material, and, like the method of the '897 patent, produces a vitreous carbon product in which the voids adversely affect the strength and structural integrity of the material.

[0012]

[0012] Furthermore, the presence of voids in glassy carbon is associated with microcracks in the micromorphology of the glassy carbon, which can subsequently propagate into the glassy carbon material during use, adversely affecting the structural integrity and performance of such materials.

[0013]

[0013] Furthermore, all of the methods in the above patents involve very long processing times for producing vitreous carbon articles, in some cases as long as 700 hours (Burton et al., U.S. Patent No. 5,182,166), making the vitreous carbon manufacturing methods unsuitable for mass commercial production. Attempts to significantly reduce the processing time have been unsuccessful.

[0014]

[0014] Microcracking is an issue with all of the glassy carbon products of the methods described in the aforementioned patents. Thus, the "thickness problem" associated with glassy carbon is not solved by the methods described in the aforementioned patents, and currently, no commercially available microcrack-free glassy carbon material is available in thicknesses greater than 4 mm.

[0015]

[0015] As a result, the art continues to address and overcome the thickness issue and seek improvements that will enable commercial-scale production of microcrack-free glassy carbon materials at thicknesses greater than 5 mm, preferably at least 7 mm. Summary of the Invention

[0016]

[0016] The present disclosure relates to glassy carbon compositions, laminates and articles and methods of making and using the same.

[0017]

[0017] In one aspect, the present disclosure relates to a micromorphologically crack-free glassy carbon article having a length and width, each of at least 10 mm, and a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm.

[0018]

[0018] In another aspect, the present disclosure relates to a micromorphologically crack-free multilayer laminated glassy carbon article comprising at least three glassy carbon layers, each having a length and width of at least 10 mm and a thickness of at least 5 mm, preferably at least 7 mm and most preferably at least 10 mm.

[0019]

[0019] In a further aspect, the present disclosure relates to a multilayer laminated glassy carbon article comprising at least two sheets of micromorphologically crack-free glassy carbon, each having a length and width of at least 10 mm and a thickness of 4 mm or less, and a bonding layer of catalyzed furfuryl alcohol between adjacent pairs of the micromorphologically crack-free glassy carbon sheets.

[0020]

[0020] A further aspect of the present disclosure relates to a multilayer laminated glassy carbon article comprising at least two sheets of micromorphologically crack-free glassy carbon, each having a length and width of at least 10 mm and a thickness of 6 mm or less, and a bonding layer of catalyzed furfuryl alcohol between adjacent pairs of the micromorphologically crack-free glassy carbon sheets.

[0021]

[0021] A further aspect of the present disclosure is a method for forming a micromorphologically crack-free glassy carbon article, each having a length and width of at least 10 mm and a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm, comprising providing first and second sheets of micromorphologically crack-free glassy carbon, each of the first and second sheets having (i) a length and width of at least 10 mm, and (ii) a thickness of 4 mm or less, but wherein the combined thickness of the first and second sheets is at least 5 mm; and The present invention relates to a method of forming a glassy carbon article having a length and width, respectively, of at least 10 mm, and a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm, the method comprising: applying a decomposable resin to a surface of a first sheet to provide a resin-bearing surface; contacting the resin-bearing surface of the first sheet with a surface of a second sheet such that the first and second sheets are solidified with the layer of resin therebetween; curing the resin between the first and second sheets to form a cured resin layer therebetween; and pyrolyzing the cured resin layer to form a micromorphologically crack-free glassy carbon article having a length and width, respectively, of at least 10 mm, and a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm.

[0022] Another aspect of the present disclosure is directed to (a) first and second sheets of micro-morphologically crack-free glassy carbon as a laminated object, each of the first and second sheets having (i) a length and width of at least 10 mm, respectively, and (ii) a thickness of 4 mm or less, but the total thickness of the first and second sheets is at least 5 mm, the first and second sheets being in contact with each other with a curable and pyrolyzable resin layer therebetween; or (b) a laminated object comprising the curable and pyrolyzable resin layer and the addition of one or more sheets of morphologically crack-free glassy carbon and / or one or more additional laminates of micro-morphologically crack-free glassy carbon and a curable and pyrolyzable resin layer therebetween, the curable and pyrolyzable resin layer ... and a heating assembly arranged to expose the laminated object or laminate stack to an elevated temperature for curing and pyrolysis of one or more curable and pyrolyzable resin layers therein.

[0023]

[0023] Yet another aspect of the present disclosure relates to a 3D printing apparatus for 3D printing a glassy carbon article, the 3D printing apparatus including: a first reservoir containing a curable and thermally decomposable resin; a first print head positioned in a resin-receiving relationship with the first reservoir; a 3D printer platform for printing the resin thereon; a controller arranged to translate the first print head to print the resin onto the 3D printer platform; and a heating assembly arranged to expose the printed resin to an elevated temperature for curing and thermal decomposition thereof to form a 3D printed glassy carbon article.

[0024] A further aspect of the present disclosure relates to a 3D printed glassy carbon article having channels defined by 3D printing and a method for making the same.

[0025]

[0025] A further aspect of the present disclosure relates to a composition comprising a cured precursor of glassy carbon or a pyrolysis product thereof, the cured precursor or pyrolysis product thereof containing a nanolattice glassy carbon filler therein.

[0026]

[0026] Yet another aspect of the present disclosure relates to a method for producing a composition comprising a cured precursor of glassy carbon or its pyrolysis product, the cured precursor or its pyrolysis product containing a nanolattice glassy carbon filler therein.

[0027]

[0027] Other aspects, features and embodiments of the present disclosure will become more particularly apparent from the ensuing description and appended claims. [Brief explanation of the drawings]

[0028] [Figure 1]

[0028] A schematic diagram of a three-layer assembly including two sheets of micromorphologically crack-free glassy carbon and a layer of catalyzed resin film on the top surface of the lower glassy carbon sheet, prior to corresponding bonding of the glassy carbon sheets to each other and the layer of catalyzed resin film therebetween. [Figure 2]

[0029] 2 is a schematic diagram of the three-layer assembly of FIG. 1 after mating bonding of the glassy carbon sheets to each other and a layer of catalyzed resin film therebetween. [Figure 3]

[0030] 3 is a schematic diagram of a six-layer composite assembly of two three-layer assemblies, each shown in FIG. 2 , and a layer of catalyzed resin film on top of the lower glassy carbon three-layer assembly, prior to mating of the glassy carbon three-layer assemblies with each other and the layer of catalyzed resin film therebetween. [Figure 4]

[0031] FIG. 2 is a schematic diagram of an apparatus for forming a glassy carbon laminate of the present disclosure, according to another embodiment. [Figure 5]

[0032] FIG. 1 is a schematic diagram of an apparatus for 3D printing a glassy carbon article according to a further embodiment of the present invention. [Figure 6]

[0033] FIG. 1 is a schematic diagram of an apparatus for 3D printing a glassy carbon article according to another embodiment of the present invention. [Figure 7]

[0034] FIG. 10 is a top view of an article having channeled glassy carbon formed by 3D printing, according to a further embodiment of the present disclosure. [Figure 8]

[0035] FIG. 10 is a schematic perspective view of a glassy carbon compressor shaft seal ring according to a further embodiment of the present disclosure. [Figure 9]

[0036] 2 is a schematic diagram of a nanolattice filler article and the steps involved in forming a glassy carbon composition according to a further aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0029]

[0037] The present disclosure generally relates to glassy carbon compositions, multilayer laminates, and 3D printed articles, as well as methods for making and using the same. In various specific aspects, the present disclosure relates to micromorphologically crack-free multilayer glassy carbon laminates and methods for making the same, such as glassy carbon laminate articles having a length and width, respectively, of at least 10 mm, and a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm. In other aspects, the present disclosure relates to glassy carbon 3D printed articles in which channels are formed in the printing process. In still other aspects, the present disclosure relates to glassy carbon precursor or pyrolytic compositions containing three-dimensional glassy carbon nanolattice objects dispersed therein.

[0030]

[0038] The present disclosure in various aspects reflects the discovery that by utilizing sheets of microcrack-free vitreous carbon material, each having a thickness of 4 mm or less (or in other embodiments 6 mm or less) and a length and width of at least 10 mm, a film of catalyzed resin, e.g., furfuryl alcohol catalyzed with a suitable catalyst, can be used as a bonding medium to form the resulting multilayer laminate, which can be processed by curing and subsequent pyrolysis operations to produce a micromorphologically crack-free, multilayer laminate vitreous carbon article having a thickness of at least 5 mm, preferably at least 7 mm, and most preferably at least 10 mm.

[0031]

[0039] The thickness of such microcrack-free glassy carbon materials and articles in the practice of the present disclosure can be any suitable thickness achievable by the manufacturing methods and techniques disclosed herein, and in certain embodiments, is at least 5 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm , 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 200 mm, 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 900 mm, 1000 mm or more in thickness. In various embodiments, the thickness of such vitreous carbon materials and articles may fall within a range defined by any of the specific numerical values ​​above as the endpoints of the range, where the lower endpoint is numerically less than the upper endpoint of such range.

[0032]

[0040] As used herein, the term "micromorphologically crack-free" refers to a glassy carbon material in which any voids or defects are less than 100 μm in size or characteristic dimension. Preferably, micromorphologically crack-free glassy carbon is a material in which any such voids or defects are less than 50 μm, less than 40 μm, less than 30 μm, less than 25 μm, less than 20 μm, less than 15 μm, less than 10 μm, less than 5 μm, less than 1 μm, less than 500 nm, less than 200 nm, less than 100 nm in size or characteristic dimension, or less than other maximum size or characteristic dimension, or within a range defined by any of the specified numerical values ​​above as range endpoints, where the lower endpoint is numerically less than the upper endpoint of such range.

[0033]

[0041] Whitmarsh's U.S. Patent No. 7,862,897 proposes the use of catalyzed resins as adhesives for bonding vitreous carbon articles; however, the articles taught by Whitmarsh in such patent are flakes or particles used to form a two-phase material in a cementitious form with non-circular pores, as described in the background section of this specification. A priori, such a method does not imply or suggest the use of sheets that solidify in a laminated structure. Whitmarsh's '897 patent does not even mention sheets or laminated structures, and instead relies on high porosity (e.g., the 13.8% porosity described in such patent) to "vent" volatile pyrolysis by-product gases from the continuous phase during their pyrolysis. It is necessarily assumed that any extended-area sheet of vitreous carbon without such high porosity would generate internal pressure due to the evolution of volatile components, which would then cause delamination of the individual sheets, resulting in failure to produce any useful final manufactured article.

[0034]

[0042] However, it has surprisingly and unexpectedly been found that by utilizing micromorphologically crack-free glassy carbon sheets of 4 mm or less, or in other embodiments 6 mm or less in thickness, together with an intervening thin film of catalyzed resin that is cured and subsequently pyrolyzed, it is possible to achieve laminated glassy carbon structures having thicknesses of greater than 5 mm for micromorphologically crack-free glassy carbon sheets of 4 mm or less in thickness, and greater than 7 mm for micromorphologically crack-free glassy carbon sheets of 6 mm or less in thickness, with similar micromorphologically crack-free properties.

[0035]

[0043] In one particularly preferred technique for forming such micromorphologically crack-free laminates, two sheets of micromorphologically crack-free glassy carbon having a thickness of 4 mm or less, and in other embodiments 6 mm or less, can be bonded together with a catalyzed resin film, which is then cured and pyrolyzed to form a three-layer laminate of two "starting sheets" of glassy carbon and an intermediate layer of glassy carbon derived from the catalyzed resin film. Such a three-layer laminate can be combined with additional glassy carbon sheets on each of its outer surfaces, bonded with a catalyzed resin film, which is then cured and pyrolyzed to form a seven-layer laminate, with the addition of additional sheets continuing on each side of the laminate until the desired thickness of the extended area micromorphologically crack-free glassy carbon article is achieved, e.g., a thickness of greater than 10 mm in each of the length and width dimensions for a starting sheet of micromorphologically crack-free glassy carbon having a thickness of 4 mm or less, and a thickness of greater than 5 mm, and a thickness of greater than 7 mm for a starting sheet of micromorphologically crack-free glassy carbon having a thickness of 6 mm or less.

[0036]

[0044] The aforementioned starting sheets of glassy carbon, each having length and width dimensions greater than 10 mm and thicknesses of 4 mm or less, and in other embodiments, 6 mm or less, are commercially available in micromorphologically crack-free sheets, for example, in thicknesses ranging from 1 mm to 4 mm, and in some cases from 1 mm to 6 mm. Useful sheets for such purposes include glassy carbon sheets commercially available under the trademark AUFA AESER from Structure Probe, Inc. (West Chester, Pennsylvania, USA), Thermo Fisher Scientific (Waltham, Massachusetts, USA), American Elements (Los Angeles, California, USA), and Millipore Sigma (St. Louis, Missouri, USA), among others. Such micromorphologically crack-free glassy carbon sheets can be formed by a variety of techniques, including, for example, crystallization, solid-state, and ultra-high-purity processes, such as sublimation.

[0037]

[0045] Referring now to the drawings, FIG. 1 is a schematic diagram of a three-layer assembly 10 including two sheets 12 and 14 of micromorphologically crack-free glassy carbon and a layer 22 of catalyzed resin film on the upper surface of the lower glassy carbon sheet 14 prior to mating bonding of the glassy carbon sheets 12, 14 to each other and the layer 22 of catalyzed resin film therebetween.

[0038]

[0046] As shown, the glassy carbon top sheet 12 has a length A, a width B, and a thickness C, where A and B each exceed 10 mm, and C is ≦4 mm in various embodiments and ≦6 mm in other embodiments. The top sheet has a top surface 16, a front surface 18, and side surfaces 20, with a back surface and a left side surface having a nature corresponding to the front surface and a nature corresponding to the right side surface 20, respectively, and a bottom surface having a nature corresponding to the top surface 16.

[0039]

[0047] Similarly, the glassy carbon bottom sheet 14 has a length and width each greater than 10 mm, and in various embodiments a thickness of 4 mm or less, and in other embodiments 6 mm or less, with sheets 12 and 14 being of corresponding dimensions relative to one another. The top surface of bottom sheet 14 has a catalyzed resin film layer 22 thereon, such that when the two sheets 12 and 14 are joinably engaged with one another by downward translation of top sheet 12 in the direction indicated by arrow L and / or upward translation of bottom sheet 14 in the direction indicated by arrow N, each sheet 12, 14 contacts the catalyzed resin film layer 22 therebetween.

[0040]

[0048] FIG. 2 is a schematic diagram of the three-layer assembly of FIG. 1 after the glassy carbon sheets have been mated together with the layers of catalyzed resin film therebetween to form a glassy carbon laminate 24.

[0041]

[0049] Once formed, the glassy carbon laminate 24 is subjected to conditions effective to cure the catalyzed resin film layer 22. The catalyzed resin utilized to form the catalyzed resin film layer 22 can be of any suitable type, including, for example, a suitable catalyst, such as a Lewis acid, e.g., H + , K. + , Mg 2+ , Fe 3+ The catalyst may include furfuryl alcohol catalyzed by sulfonic acid, maleic acid, or maleic anhydride, which are effective at room temperature. Other catalysts, such as zinc chloride, ferric chloride, ammonium chloride, magnesium chloride, and ammonium sulfate, polymerize furfuryl alcohol at elevated temperatures. As a specific example, zinc chloride rapidly polymerizes furfuryl alcohol at temperatures between about 90°C and 100°C. In various embodiments, the catalyst may be a mixture of a fast ambient temperature catalyst and a high temperature catalyst, whereby the polymerization of furfuryl alcohol to poly(furfuryl alcohol) occurs at ambient conditions with a rapid "cure" followed by exposure to elevated temperatures effective for the catalytic action of the high temperature catalyst to achieve the desired polymerization completion.

[0042]

[0050] Conditions suitable for polymerizing (curing) the layer of catalyzed resin film can include ambient and / or elevated temperature conditions depending on the nature of the catalyst, and can include pressure conditions of various natures, such as ambient, superatmospheric, or subatmospheric pressure, as needed or desired for a particular application of the disclosed method. Polymerization conditions can further include exposing the layer of catalyzed resin film to penetrating, curing-effective radiation, such as ultraviolet (UV) radiation, infrared (IR) radiation, microwave radiation, electron beam radiation, or any other radiation effective to cure the resin film as a bonding medium for the micromorphologically crack-free glassy carbon sheets interposed therebetween.

[0043]

[0051] In various embodiments of the present disclosure, the curable resin film between the micromorphologically crack-free glassy carbon sheets may not require a catalyst and may be curable by exposure to heat and / or radiation alone.

[0044]

[0052] Because curing of the curable resin film can produce volatile reaction by-products, such as water vapor, during the curing polymerization of the furfuryl alcohol resin to form poly(furfuryl alcohol), it may be desirable to solidify the micromorphologically crack-free glassy carbon sheets and the resin film therebetween under mechanically applied pressure on one or more outer surfaces of each glassy carbon sheet to prevent the volatile reaction by-products from the curing operation from separating or delaminating the glassy carbon sheets or glassy carbon laminate during the curing operation. Furthermore, it may be desirable to perform the curing of the curable resin film between each micromorphologically crack-free glassy carbon sheet under reduced pressure or vacuum conditions, for example, in a reactor evacuated by a suitable vacuum pumping system. In some embodiments, it may be advantageous to perform the curing under ultra-high vacuum conditions for such purposes, using a vacuum pump to achieve such conditions, and optionally using a chemisorbent material to irreversibly chemically react with the volatile by-products of the curing process, thereby improving the efficiency of the curing process.

[0045]

[0053] Thus, hardening of the bonding medium between micromorphologically crack-free glassy carbon sheets can be accomplished under mechanical pressure, heat, and / or gas (vapor) pressure conditions, as necessary or desirable for the particular implementation of the disclosed method, using a "stack" of glassy carbon sheets and solidifying bonding medium films between intervening adjacent glassy carbon sheets.

[0046]

[0054] Generally, the thickness of the film of bonding medium between adjacent glassy carbon sheets can be any suitable thickness of such bonding medium that is effective to bond the adjacent glassy carbon sheets to each other across the entire area of ​​their respective faces when the surfaces of the two faces are aligned with each other. In various embodiments, the thickness of the bonding medium film can be 0.01 mm to 0.5 mm or more, more preferably 0.03 mm to 0.3 mm or more, or other thickness ranges or specific values ​​as needed for a particular application. In other embodiments, the thickness of the bonding medium film may be in the range of 0.05 mm to 1 millimeter or more, or may be within a range whose endpoints are selected from among 0.05 mm, 0.10 mm, 0.15 mm, 0.20 mm, 0.25 mm, 0.30 mm, 0.35 mm, 0.40 mm, 0.45 mm, 0.50 mm, 0.55 mm, 0.60 mm, 0.65 mm, 0.70 mm, 0.75 mm, 0.80 mm, 0.85 mm, 0.90 mm, 0.95 mm, and 1.0 mm, where the lower endpoint is numerically less than the upper endpoint of such range. The film of curable bonding medium can be applied by any suitable method, including, but not limited to, brushing, spraying, roller coating, dip coating, vapor deposition, or other suitable method or technique.

[0047]

[0055] Curing conditions for curing a resin film between glassy carbon sheets, between glassy carbon laminates, and / or between glassy carbon sheets and glassy carbon laminates, involving adjustment of process conditions under the control of a central processor unit (CPU), such as adjustment of temperature over time, adjustment of gas (vapor) pressure over time, and / or adjustment of any other conditions effective to effect hardening of the cured resin between the glassy carbon sheets, between glassy carbon laminates, and / or between the glassy carbon sheet and glassy carbon laminate. Curing can be achieved by applying mechanical pressure to one or more outer surfaces of the glassy carbon sheets and / or laminates, whereby hardening and solidification occur without causing separation and delamination.

[0048]

[0056] 3 is a schematic diagram of a six-layer composite assembly of two three-layer glassy carbon laminates 24 and 26, each constructed as shown in FIG. 2, with a layer of catalyzed resin film on top of the bottom three-layer glassy carbon laminate, prior to mating of the respective three-layer glassy carbon laminates with the layer of catalyzed resin film therebetween. The mating of the respective glassy carbon laminates 24 and 26 with each other is achieved by translating the top laminate 24 downward in the direction indicated by arrow L and / or the bottom laminate 26 upward in the direction indicated by arrow N, so that each laminate 24 and 26 contacts the layer of catalyzed resin film 22 therebetween.

[0049]

[0057] It will be appreciated that the method illustratively described in connection with FIGS. 1-3 above can be carried out sequentially, in an appropriate manner, such that a constituent stack of a number of laminates is produced and the respective laminates are combined and bonded together, or that a laminate stack is formed in a sequential manner and glassy carbon sheets are added thereto.

[0050]

[0058] After the resin has cured, the cured resin between adjacent glassy carbon sheets can be pyrolyzed. This can be done in any suitable manner. For example, a three-ply laminate including two glassy carbon sheets and a layer of cured resin therebetween can be subjected to conditions that pyrolyze the cured resin to form a glassy carbon laminate. A layer of curable resin can then be applied to one side of the laminate, followed by contacting the resin-bearing surface of the first laminate with the surface of the second laminate, solidifying the two laminates through curing and subsequent pyrolysis of the resin. This allows a second glassy carbon laminate including a glassy carbon interlayer of pyrolyzed resin between the first provided glassy carbon sheets to be bonded onto the first provided glassy carbon laminate including a glassy carbon interlayer of pyrolyzed resin between the first provided glassy carbon sheets. In this manner, a laminate subassembly block can be formed, which can then be solidified with other laminate subassembly blocks to form a glassy carbon laminate product of a desired thickness.

[0051]

[0059] Pyrolysis of the cured resin (binding medium) can be carried out as part of a continuous process operation, with pyrolysis initiated immediately after curing, such as in the same reactor adapted to provide the necessary curing and pyrolysis conditions, or the laminate with the previously cured resin interlayer can be subsequently subjected to pyrolysis conditions in a time-separated curing and pyrolysis process. For mass production purposes, a series of curing and pyrolysis vessels can be used, with the curable resin application process occurring upstream of the resin curing vessel, whereby resin application, curing, and pyrolysis of the glassy carbon sheet and / or glassy carbon laminate occur in separate stages of the process system.

[0052]

[0060] The pyrolysis conditions can be achieved by adjusting process conditions under the control of a central processor unit (CPU), such as adjusting temperature over time, adjusting gas (vapor) pressure over time, and / or adjusting any other conditions effective to effect curing of the cured resin between the glassy carbon sheets, between the glassy carbon stacks, and / or between the glassy carbon sheets and the glassy carbon stacks. The pyrolysis can be effected by applying mechanical pressure to the outer surfaces of the glassy carbon sheets and / or stacks, whereby curing and solidification occur without causing separation and delamination.

[0053]

[0061] For example, the pyrolysis operation can include pressure conditions of various natures, such as ambient, superatmospheric, or subatmospheric, as needed or desired for a particular application. The pyrolysis conditions can further include exposure to radiation, such as ultraviolet (UV) radiation, infrared (IR) radiation, microwave radiation, electron beam radiation, or other radiation.

[0054]

[0062] The processing of the glassy carbon sheets and glassy carbon laminates in their respective curing and pyrolysis operations involves the use of a variable frequency microwave generator or oven whose frequency is adjusted to effect the curing and pyrolysis of the resin interlayer, or an arrangement of a series of variable frequency microwave ovens in which an upstream oven or chamber is used for curing and a downstream oven or chamber is used for pyrolysis for batch, semi-batch or continuous production of glassy carbon laminate products.

[0055]

[0063] Curing of the applied resin and pyrolysis of the cured resin can be accomplished using the same or different heating devices or combinations of heating devices, with the same or different heating modalities, such as one or more of conductive, convective, and radiative heating of the resin. The heating device can provide radiative heating of the resin with any suitable electromagnetic radiation, such as infrared, microwave radiation, ultraviolet, or radiation in other portions of the electromagnetic spectrum to which the resin responds for heating to effect curing and / or pyrolysis of the resin. For example, electron beam devices can also be used, such as in a rastering assembly or printhead assembly in 3D printing of glassy carbon materials, as described in more detail below.

[0056]

[0064] In the practice of the present disclosure in which microwave radiation is used, such radiation can be used to effect or accelerate the curing of the resin between glassy carbon sheets, or between glassy carbon sheets and previously formed glassy carbon laminates, or between previously formed glassy carbon laminates. For example, polymerization of the resin can be mediated by microwave radiation and thermal decomposition of the cured resin; therefore, microwave radiation can be used at any post-cure or cured stage, from the initiation of cure to the completion of thermal decomposition of the resin; and resin processing can be carried out using a hybrid system that includes microwave radiation oscillation in conjunction with other heating systems during the entire processing cycle or any part or portion thereof. Microwave curing can be particularly beneficial in various applications to achieve longer and more effective crosslinking of crosslinkable resins.

[0057]

[0065] In the context of the foregoing considerations, it will be appreciated that resin chemistries can be selected or modified for sensitivity to microwave radiation or other heating regimes, and that resin chemical synthesis or conversion rates can be improved or optimized by modifying the selection of initial chemistry for such purposes. More generally, additive selection and / or resin modification can be made to achieve desired synthesis conversion rates and efficiencies in the production of the glassy carbon laminate articles of the present disclosure.

[0058]

[0066] FIG. 4 is a schematic diagram of an apparatus for forming a glassy carbon laminate of the present disclosure, according to another embodiment.

[0059]

[0067] The apparatus shown in FIG. 4 includes a reaction vessel 30 defining an interior volume 32 in which a stack of vitreous carbon sheets and / or laminate articles 34, 36, 38, and 40 are placed between hydraulic press support plates 42 and 54 and processed.

[0060]

[0068] The hydraulic press support plate 42 is associated with a hydraulic press drive assembly 44 which includes a hydraulic press drive shaft 46 which can be driven in either an upward or downward direction as desired, but is shown in Figure 4 as being driven downward in the direction indicated by arrow L, to create pressure on the stack of glassy carbon sheets and / or laminate articles 34, 36, 38 and 40 during processing of such sheets and / or articles. The hydraulic press drive shaft 46 is sealed in its passage into the interior volume 32 of the reaction vessel by a hydraulic press drive shaft seal 48.

[0061]

[0069] The hydraulic press support plate 50 is associated with a hydraulic press drive assembly 52 which includes a hydraulic press drive shaft 54 ​​which can be driven in either an upward or downward direction as desired, but is shown in Figure 4 as being driven upward in the direction indicated by arrow N to apply pressure to the stack of glassy carbon sheets and / or laminated articles 34, 36, 38 and 40 during processing of such sheets and / or articles. The hydraulic press drive shaft 54 ​​is sealed in its passage into the interior volume 32 of the reaction vessel by a hydraulic press drive shaft seal 56.

[0062]

[0070] The upper hydraulic press drive assembly 44 is associated with a coolant assembly housing 58, which is bolted to the hydraulic press drive assembly by housing mounting bolts 60. The coolant is simply a housing service, a coolant manifold 62 in the hydraulic press support plate 42, and coolant circulates through passages in the coolant manifold 62 from a coolant reservoir 72, which is connected to a coolant flow circuit including a coolant supply line 64 and a coolant return line 66, the return line containing a chiller 70 for removing heat (represented by heat flux Q1) from the coolant, and the supply line 64 containing a pump 68 for maintaining circulation of the coolant through the flow circuit.

[0063]

[0071] The upper hydraulic press drive assembly 40 is associated with a heat pipe cooling arrangement for the hydraulic press support plate 50, which includes a heat pipe mounting plate channel 74 therein. The heat pipe mounting plate channel 74 is in fluid flow communication with a heat pipe tubular passage 76 in the hydraulic press drive shaft 54, the lower end of which is in heat exchange relationship with a heat exchange coil 78 in the hydraulic press drive assembly. The heat exchange coil 78 is connected to a coolant circulation line 84, which is connected to a coolant reservoir 80 that provides coolant that is pumped through the heat exchange coil 78 and through the coolant circulation line 84 by a pump 82. The coolant circulation line 84 includes a coolant chiller 86 in a return line portion thereof for removing heat (represented by heat flux Q2) from the coolant as it returns to the coolant reservoir, from which it is circulated by operation of the pump 82 to the heat exchange coil 78.

[0064]

[0072] With the respective coolant arrangements provided, each hydraulic press support plate 42 and 50 provides an extended area heat exchange surface for removing heat from the stack of vitreous carbon sheets and / or laminate articles 34, 36, 38, and 40 during processing of such sheets and / or articles. It will be appreciated that the particular coolant arrangements shown may be varied in implementation of the processing apparatus, and that the coolant arrangement shown in association with the upper hydraulic press support plate 42 may also be utilized to cool the lower hydraulic press support plate 50, or alternatively, the coolant arrangement shown in association with the lower hydraulic press support plate 50 may also be utilized to cool the upper hydraulic press support plate 42. It will further be appreciated that any other cooling or heat removal techniques and devices may be used to thermally regulate the temperature within the stack of vitreous carbon sheets and / or laminate articles 34, 36, 38, and 40 during processing.

[0065]

[0073] It will be appreciated that although each cooling arrangement is shown in connection with an upper hydraulic press support plate and a lower hydraulic press support plate, each arrangement may be adapted to heat the stack of vitreous carbon sheets and / or laminate articles 34, 36, 38 and 40 during processing of such sheets and / or articles by providing a heating device rather than a chiller in the respective flow circuit.

[0066]

[0074] Additionally, the use of heat exchangers in each flow circuit provides fluid heating and cooling capabilities in such flow circuits to adjust the temperature within the stack of glassy carbon sheets and / or laminate articles 34, 36, 38, and 40 during processing of such sheets and / or articles by heating or cooling the stack as needed during processing. For example, flow circuits can be used to cool the stack during catalyzed resin polymerization to dissipate heat and control the time-temperature relationship during the polymerization operation, and flow circuits can be used to heat the stack during a pyrolysis operation after polymerization is complete. For example, the final product laminate can be solidified under mechanical pressure to heat the previously polymerized resin bonding medium.

[0067]

[0075] The reaction vessel 30 is shown in FIG. 4 as also having a variable frequency microwave generator 88 mounted on its sidewall, which is powered by a microwave power line 90 connected to the variable frequency microwave generator.

[0068]

[0076] For example, a variable frequency microwave generator can be used to impinge microwave radiation M onto the stack mounted within the reaction vessel during polymerization and / or pyrolysis operations, the microwave generator controllably operated at a variable frequency to provide a selected microwave radiation intensity corresponding to such heating. The variable frequency microwave generator can be connected via signal transmission lines to a processor or controller (CPU) for regulating the microwave generator to effect microwave heating of the resin material according to a predetermined time-temperature schedule to effect polymerization and / or subsequent pyrolysis of the resin material.

[0069]

[0077] The reactor vessel 30 is shown in FIG. 4 as also having a vacuum pump exhaust line 94 communicating through the reactor vessel wall with the reactor vessel's interior volume 32, and for exhausting gases from the interior volume as an effluent indicated by arrow E by the action of the vacuum pump 92 in such exhaust line. The exhaust line may optionally further include a chemical sorbent canister 96 upstream of the vacuum pump for removing reaction product gas species that are desirably minimized in the gas flow to the vacuum pump. The vacuum pump may be operated correspondingly during processing of the stack in the reactor to remove gases evolved from the stack and ensure a completely microcrack-free quality of the stack at the end of processing.

[0070]

[0078] It will be appreciated that the processing equipment shown in FIG. 4 is merely illustrative in nature, and that the structure, components, and operation of the processing equipment may be widely varied in the general practice of the present disclosure to produce glassy carbon laminates with desired properties.

[0071]

[0079] Furthermore, although the glassy carbon sheets and laminates are shown as being rectangular in configuration, it will be recognized that the specific shapes of the sheets and laminates may vary in the practice of this disclosure.

[0072]

[0080] The apparatus shown in FIG. 4 diagrammatically includes a central processor unit (CPU) 65 shown generally with signal transmission lines 67 capable of carrying bidirectional signals to and from the CPU 65, whereby the CPU is connected by a number of signal transmission lines to any one or components in the apparatus as required, including any of the components of the apparatus shown, such as a pump, a chiller, a microwave generator, a hydraulic press application or additional temperature sensing elements, pressure sensing elements, flow regulators, humidity monitors or any other component, assembly or element of the apparatus system.

[0073]

[0081] FIG. 5 is a schematic diagram of an apparatus 98 for 3D printing glassy carbon articles according to a further embodiment of the present invention.

[0074]

[0082] A 3D printing apparatus 98 can be used to form a 3D printed glassy carbon article 100 on a 3D printer platform 102 by supplying a curable and thermally decomposable resin from a resin reservoir 112 to a first print head 104, which is translated in the xy plane and incrementally adjusted in the z direction during the course of printing. The print head 104 is translationally controlled by a central processor unit (CPU) 108, which is connected in signal transmission relationship to the print head 104 by a CPU signal transmission line 110, shown in dashed line in FIG. 4 . Concurrent with the printing of resin from the first print head 104, catalyst is supplied from a catalyst reservoir 114 to the second print head 106 in response to control signals transmitted from the CPU to such print head; the second print head 106 is similarly translated and in a tracking relationship with the print head 104, as controlled by the CPU 108 via signal transmission lines 110 interconnecting the CPU and print head 106, and the print head 106 prints the catalyst onto the resin printed by the print head 104. The 3D printing system 98 in the embodiment shown in FIG. 4 includes a variable frequency microwave generator 116 arranged to impinge microwave radiation M at variable microwave intensity onto the 3D printed article to polymerize and subsequently pyrolyze the printed material. For such purpose, the variable frequency microwave generator 116 can be coupled to the CPU 108 by signal transmission lines 110 as shown, thereby controlling the supply of microwave radiation to the 3D printed material during the respective polymerization and pyrolysis processes.

[0075]

[0083] In other embodiments, a heating assembly can be used in place of the variable frequency microwave generator to perform the curing and pyrolysis operations under elevated temperature conditions. The 3D printing apparatus 98 in various embodiments can include a chamber in which 3D printing occurs via the components of the apparatus shown schematically in FIG. 5. In a manner similar to the reaction vessel of FIG. 4, this chamber can be connected to a vacuum pump that communicates with the interior volume of the chamber and is operated to maintain reduced pressure conditions during the 3D printing operation.

[0076]

[0084] Figure 6 is a schematic diagram of an apparatus 101 for 3D printing a glassy carbon article according to another embodiment of the present invention. In Figure 6, to print a resin and catalyst mixture onto a 3D printer platform 120 to form a glassy carbon article 118, a 3D printing apparatus, a resin reservoir 128, and a catalyst reservoir 130 are arranged to provide the resin and catalyst in delivery lines to a print head 122 to form the mixture, and the print head 122 is translated in the xy plane and incrementally adjusted in the z direction during the course of printing.

[0077]

[0085] A CPU 124 is shown coupled in signal transmission relationship to the print head 122 by CPU signal transmission lines 126 to control print head translation as needed. Such a system employs a variable frequency microwave generator 132 arranged to impinge microwave radiation M at variable microwave intensities onto the 3D printed article to polymerize and subsequently pyrolyze the printed material. For such purposes, the variable frequency microwave generator 132 can be coupled to the CPU 124 by signal transmission lines 126 to provide a controlled supply of microwave radiation to the 3D printed material during the respective polymerization and pyrolysis processes.

[0078]

[0086] It will be appreciated that other radiation or heat sources can be used in the 3D printing system instead of the variable frequency microwave generator, and other arrangements of the variable frequency microwave generator can be used. For example, a 3D printing system can be used in which the print head is present in an assembly that also includes an electron beam delivery device in tracking relationship with the print head, so that after printing the resin or resin and catalyst mixture, the printed resin or resin and catalyst mixture is subsequently but simultaneously irradiated with an electron beam to cure or cure and pyrolyze the resin, such as by a print head assembly that includes, in addition to the print head, a first electron beam delivery device in tracking relationship with the print head to cure the resin, and a second electron beam delivery device in tracking relationship with the first electron beam delivery device to pyrolyze the cured resin. In this way, a sufficient pyrolysis beam is gradually applied to the 3D printed article at a controlled temperature that can be adjusted according to a predetermined temperature-time schedule to produce a glassy carbon article of the product with desired size, shape, and thickness characteristics.

[0079]

[0087] Like the 3D printing apparatus shown in Figure 5, the 3D printing apparatus shown in Figure 6 can utilize a heating assembly to perform the curing and pyrolysis operations under high temperature conditions instead of a variable frequency microwave generator. The 3D printing apparatus 101 in various embodiments can also include a chamber in which 3D printing occurs via the components of the apparatus shown schematically in Figure 6. In a manner similar to the reaction vessel of Figure 4, this chamber can be connected to a vacuum pump that communicates with the interior volume of the chamber and is operated to maintain reduced pressure conditions during the 3D printing operation.

[0080]

[0088] FIG. 7 is a top view of a channeled glassy carbon article 136 formed by 3D printing, such as a bearing element for use in a roller bearing assembly or other bearing application, according to a further embodiment of the present disclosure.

[0081]

[0089] Channeled glassy carbon articles 136 include 3D printed objects 138 that include 3D-printed channels 140 therein. Such glassy carbon articles can be formed, for example, by printing strands of a curable and pyrolyzable resin that include x-axis and y-axis strands that form a "screen" configuration, with gaps defined between each parallel-aligned strand and its orthogonal intersecting strand. These gaps or channels subsequently form an open matrix within which volatile gas products of the curing and pyrolysis reactions can escape, thereby preventing internal or delamination stresses in the material as a result of the generation of such volatile gas products.

[0082]

[0090] Thus, in a 3D printing operation, successive printed layers of an article can be printed such that the gaps between the resin strand elements are aligned with one another, i.e., they form through-holes in the resulting cured resin article or subsequent glassy carbon pyrolysis product, or alternatively, successive printed layers of an article can be printed such that such gaps are offset with respect to one another such that the paths of the gaps formed are tortuous, but still communicate with one another in immediately preceding and subsequent layers of the printed article.

[0083]

[0091] In this method, a 3D printed article can be formed by 3D printing using a suitable type of 3D printing apparatus, such as the printing system shown schematically in FIGS. 5 and 6, where 3D printing can be performed by exposing the material to curing radiation at or after printing, or curing can be performed by exposing the 3D printed material to high temperature conditions at or after 3D printing, and after the 3D printed article is formed, the cured resin article can then be exposed to pyrolysis conditions effective to form an article of a glassy carbon product.

[0084]

[0092] Thus, such 3D printing of channeled glassy carbon precursor articles addresses the issue of thickness, allows for hardening and subsequent pyrolysis of the printed material, and prevents the formation of microcracks in the printed article, resulting in a microcrack-free nature of the resulting article.

[0085]

[0093] 3D printing can be performed in a variety of patterns to create channeled 3D printed structures.

[0086]

[0094] 8 is a schematic perspective view of a glassy carbon compressor shaft seal ring 142 according to a further embodiment of the present disclosure, including a cylindrical body 144 defining an inner surface bounded by a cylindrical opening through which a rotating or reciprocating shaft of a compressor device fits into the seal ring, with 3D-printed holes 148 formed in the cylinder as channels in the glassy carbon article, allowing free evolution of gases from the corresponding precursor article during the respective curing and pyrolysis steps during previous processing. This allows for the production of seal rings or other glassy carbon articles having substantial thicknesses, e.g., 2-10 cm or more, and having microcrack-free properties.

[0087]

[0095] FIG. 9 is a schematic illustration of a nanolattice filler article 150 and the steps involved in forming a glassy carbon composition according to a further embodiment of the present invention.

[0088]

[0096] The nanolattice filler article 150 is of a type recently reported in Crook, C. et al., Plate-nanolattices at the theoretical limit of stiffness and strength, Nature Communications, 2020, 11: 1579, https: / / doi.Org / 10.1038 / s41467-020-15434-2, www.nature.com / naturecommunications (accessed May 1, 2020, the disclosure of which is incorporated herein by reference). Crook et al. describe forming defect-free pyrolytic carbon nanolattices comprised of closed-cell plate structures by fabrication involving two-photon lithography and pyrolysis according to techniques disclosed therein to form pyrolytic carbon nanolattice cubic articles having 100-160 nm diameter holes in the center of the plate faces. These glassy carbon nanolattice cube articles have a substantial internal void volume and dimensions that can be, for example, about 5 μm on a side (ie, 5 μm×5 μm×5 μm).

[0089]

[0097] According to a further aspect of the present disclosure, glassy carbon nanolattice cube articles are utilized as fillers in precursor resins that are cured and subsequently pyrolyzed to form glassy carbon articles. Because of their glassy carbon structure, they do not present thermal expansion coefficient or chemical compatibility issues, and because of their high strength and stiffness, they impart high strength to glassy carbon materials containing them.

[0090]

[0098] 9 shows a schematic representation of one glassy carbon nanolattice cube article as representative of many articles that constitute the filler that is added under vacuum to the precursor resin for the final glassy carbon article in step 152. The introduction and maintenance of vacuum in this step is important because the cube article contains voids and is evacuated under vacuum conditions. Thus, although the nanolattice cube article in this step is evacuated, the small face opening dimensions of such articles and the associated surface tension effects will prevent the precursor resin from penetrating into the interior volume of the nanolattice cube article.

[0091]

[0099] Next, in step 154, the resin containing the nanolattice cube articles as a filler is cured under vacuum conditions. The nanolattice cube article filler content in the resin is selected so that gases evolved during the curing operation enter the evacuated internal voids in the nanolattice cube articles, thereby functioning to retain and contain such gases, and so that such evolved gases do not contribute to void formation, cracks, and microcracks in the final glassy carbon composition. This gas-trapping action by the nanolattice cube articles is then continued in step 156, where the cured resin is pyrolyzed under vacuum conditions, and the pyrolysis by-product gases also enter and are subsequently contained within the nanolattice cube articles.

[0092]

[0100] Such processing can form a glassy carbon composition having nanolattice cube articles therein as fillers that receive the evolved gas, wherein the glassy carbon composition is free of microcracks, but has high strength due to the presence of the nanolattice cube articles therein, and the gas contained within the nanolattice cube articles serves to reduce the overall density of the glassy carbon composition, making it substantially stronger and lighter than conventional glassy carbon materials.

[0093]

[0101] It will therefore be appreciated that the present disclosure provides various methods for achieving thick glassy carbon compositions and articles that can be utilized in the manufacture of a variety of articles such as, but not limited to, pump and compressor seals, brake linings, electric vehicle pantographs, spacecraft heat shields, and articles useful in tribological, mechanical, and electrical applications.

[0094]

[0102] While the present disclosure has been described herein with reference to particular aspects, features, and illustrative embodiments, it will be recognized that the utility of the present disclosure is not so limited, but rather extends to and includes numerous other variations, modifications, and other embodiments, as would be suggested to those skilled in the art of the present disclosure based on the description herein. Correspondingly, the claims provided below are intended to be broadly interpreted and interpreted to include all such variations, modifications, and other embodiments within their spirit and scope. [Explanation of symbols]

[0095] 10 3 layer assembly 12 Upper glassy carbon sheet 14 Bottom glassy carbon sheet 16 Top side 18 Front 20 Side 22 layers of catalyzed resin film 24 Glassy carbon laminate 26 Glassy carbon laminate 30 reaction vessels 32 internal volume 34 Glassy carbon sheet or laminate 36 Glassy carbon sheet or laminate 38 Glassy carbon sheet or laminate 40 Glassy carbon sheet or laminate 42 Hydraulic press support plate 44 Hydraulic press drive assembly 46 Hydraulic press drive shaft 48 Hydraulic press drive shaft seal 50 Hydraulic press support plate 52 Hydraulic press drive assembly 54 Hydraulic press drive shaft 56 Hydraulic press drive shaft seal 58 Coolant assembly housing 60 Housing mounting bolt 62 Coolant manifold 64 Coolant supply line 65 Central Processor Unit (CPU) 66 Coolant return line 67 Signal Transmission Line 68 Pump 70 Refrigerant Chiller 72 Coolant reservoir 74 heatpipe mounted plate channels 76 Heat pipe tubular passage 78 Heat exchange coil 80 Coolant Reservoir 82 Pump 84 Coolant circulation line 86 Refrigerant Cooler 88 Variable Frequency Microwave Oscillator 90 Microwave Oscillator Power Line 92 Vacuum Pump 94 Vacuum pump exhaust line 96 Chemical Sorbent Canister 98 3D Printing System 100 3D printed glass-like carbon articles 101 3D Printing System 102 3D Printer Platform 104 print head 106 print head 108 Central Processor Unit (CPU) 110 CPU signal transmission line 112 Resin Reservoir 114 Catalyst Reservoir 116 Variable Frequency Microwave Oscillator 118 3D printed glassy carbon articles 120 3D printer platforms 122 print head 124 Central Processor Unit (CPU) 126 CPU signal transmission line 128 Resin Reservoir 130 Catalyst Reservoir 132 Variable Frequency Microwave Oscillator 136 Bearings 138 3D printed matter 140 channels 142 Compressor shaft seal ring 144 Cylinder 146 Inside 148 3D printed holes 150 Nanolattice Filler Articles 152 Filler and resin blending 154 Curing of resin compositions 156 Thermal decomposition of cured resin

Claims

1. 1. A micromorphologically crack-free, multi-layer laminated vitreous carbon article, comprising at least two micromorphologically crack-free, glassy carbon sheets, each having a length and width of at least 10 mm, each having a thickness of 6 mm or less, wherein adjacent sheets in the multi-layer laminated vitreous carbon article are bonded to one another by a pyrolyzed film glassy carbon interlayer therebetween, the pyrolyzed film glassy carbon interlayer being formed from catalyzed furfuryl alcohol.

2. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1, wherein said sheets of micromorphologically crack-free vitreous carbon each have a thickness of 4 mm or less.

3. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1 having a thickness in the range of 5 to 1000 mm.

4. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1 having a thickness of at least 5 mm.

5. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1, wherein said thickness is at least 7 mm.

6. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1 having a thickness of at least 10 mm.

7. 10. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 1, wherein the catalyzed furfuryl alcohol tie layer is at least partially polymerized.

8. 10. The micromorphologically crack-free multilayer laminated vitreous carbon article of claim 1, comprising at least two sheets of micromorphologically crack-free vitreous carbon, each of said at least two sheets of micromorphologically crack-free vitreous carbon formed by a crystallization, solid state, or sublimation process.

9. 9. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 8 having a thickness of at least 5 mm.

10. 9. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 8 having a thickness of at least 7 mm.

11. 9. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 8 having a thickness of at least 10 mm.

12. 9. The micromorphologically crack-free multi-layer laminated vitreous carbon article of claim 8, having a thickness in the range of 5 to 1000 mm.

13. 1. A method for forming a micromorphologically crack-free multi-layer laminated vitreous carbon article having a length and width each of at least 10 mm and a thickness of at least 5 mm, comprising: providing first and second sheets of micromorphologically crack-free glassy carbon, each of the first and second sheets having (i) a length and width, respectively, of at least 10 mm, and (ii) a thickness of no more than 4 mm, with the combined thickness of the first and second sheets being at least 5 mm; applying a curable and thermally decomposable resin comprising furfuryl alcohol and a curing catalyst to a surface of the first sheet to provide a resin-bearing surface; contacting the resin-bearing surface of the first sheet with a surface of the second sheet such that the first and second sheets are solidified with the layer of resin therebetween; curing the resin between the first and second sheets to form a cured resin layer therebetween; pyrolyzing the cured resin layer to form the micromorphologically crack-free multi-layer laminated vitreous carbon article having a length and width each of at least 10 mm and a thickness of at least 5 mm; A method comprising:

14. applying the curable and thermally decomposable resin to (a) a surface of a third sheet of micromorphologically crack-free glassy carbon, or (b) a surface of the micromorphologically crack-free glassy carbon article having a length and width, respectively, of at least 10 mm and a thickness of at least 5 mm, to provide a resin layer on the surface to which the curable and thermally decomposable resin is applied; contacting the third sheet with the micromorphologically crack-free multi-layer laminated vitreous carbon article such that the third sheet and the micromorphologically crack-free multi-layer laminated vitreous carbon article are solidified with the resin layer therebetween; curing the resin layer between the third sheet and the micromorphologically crack-free glassy carbon article to form a cured resin layer therebetween; pyrolyzing the cured resin layer between the third sheet and the micromorphologically crack-free multi-layer laminated vitreous carbon article to form a micromorphologically crack-free multi-layer laminated vitreous carbon article of increased thickness; 14. The method of claim 13, further comprising:

15. 15. The method of claim 14, wherein the step involving the third sheet of micromorphologically crack-free vitreous carbon is repeated for at least a fourth sheet of micromorphologically crack-free vitreous carbon to form a micromorphologically crack-free multi-layer laminated vitreous carbon article of even further increased thickness.

16. repeating the steps with the first and second sheets of micromorphologically crack-free glassy carbon to produce the micromorphologically crack-free multi-layer laminate vitreous carbon article as a first glassy carbon laminate, each having a length and width of at least 10 mm and a thickness of at least 5 mm, with third and fourth sheets of micromorphologically crack-free glassy carbon to form a second micromorphologically crack-free multi-layer laminate vitreous carbon article as a second glassy carbon laminate, each having a length and width of at least 10 mm and a thickness of at least 5 mm; applying the curable and heat-decomposable resin to one surface of the first and second laminates to form a resin layer thereon; contacting the first and second laminates with each other such that the first and second laminates are solidified with the resin layer therebetween; curing the resin layer between the first and second laminates to form a cured resin layer therebetween; pyrolyzing the cured resin layer between the first and second laminates to form a micromorphologically crack-free multi-layer laminated vitreous carbon article of further increased thickness; and 14. The method of claim 13, further comprising:

17. 17. The method of claim 16, comprising repeating the step with the second stack of micromorphologically crack-free multi-layer laminated vitreous carbon articles of further increased thickness with a third stack of micromorphologically crack-free vitreous carbon to produce micromorphologically crack-free multi-layer laminated vitreous carbon articles of even further increased thickness.

18. 17. The method of claim 16, comprising repeating the step with the second laminate to produce the micromorphologically crack-free multi-layer laminate vitreous carbon article of further increased thickness with additional sheets of micromorphologically crack-free vitreous carbon to produce a micromorphologically crack-free multi-layer laminate vitreous carbon article of even further increased thickness.

19. 14. The method of claim 13, comprising adding one or more additional sheets of micromorphologically crack-free glassy carbon and / or one or more additional stacks of micromorphologically crack-free glassy carbon to the micromorphologically crack-free, multi-layer laminate vitreous carbon article, each having a length and width of at least 10 mm and a thickness of at least 5 mm, applying the curable and pyrolyzable resin to form an underlying resin layer of each added sheet and / or added stack, curing each underlying resin layer, and pyrolyzing each cured underlying resin layer to form a solidified stack to form a solidified multi-layer laminate micromorphologically crack-free glassy carbon article.

20. The method of claim 13 , wherein the curing catalyst comprises a Lewis acid.

21. The Lewis acid is H ＋ , K. ＋ , Mg ２＋ , Fe ３＋ , B.F. ３ , CO ２ , S.O. ３ , RMgX, AlCl ３ and Br ２ 21. The method of claim 20, comprising one or more of:

22. 14. The method of claim 13, wherein the curing catalyst comprises a sulfonic acid, maleic acid, or maleic anhydride.

23. 14. The method of claim 13, wherein the curing catalyst comprises zinc chloride, ferric chloride, ammonium chloride, magnesium chloride, or ammonium sulfate.

24. 24. The method of claim 23, wherein the curing catalyst comprises zinc chloride.

25. The method according to any one of claims 13 to 19, wherein the curable and thermodecomposable resin is cured at reduced pressure.

26. The method according to any one of claims 13 to 19, wherein the curable and thermodecomposable resin is cured at an elevated temperature.

27. The method according to any one of claims 13 to 19, wherein the curable and heat-decomposable resin is cured by radiation curing.

28. 28. The method of claim 27, wherein the radiation curing comprises one or more of ultraviolet (UV) radiation, infrared (IR) radiation, microwave radiation, and electron beam radiation.

29. 28. The method of claim 27, wherein the radiation curing comprises microwave radiation.

30. 30. The method of claim 29, wherein the microwave radiation is generated by a variable frequency microwave oscillator.

31. 20. The method of any one of claims 13 to 19, wherein the curable and thermodecomposable resin is applied to a thickness in the range of 0.01 mm to 0.5 mm.

32. 32. The method of claim 31, wherein the applied thickness is in the range of 0.03 mm to 0.3 mm.

33. 20. The method of any one of claims 13 to 19, wherein the curable and thermally decomposable resin is applied by brushing, spraying, roller coating, dip coating or vapor deposition.

34. 20. The method according to any one of claims 13 to 19, wherein the curable and thermodecomposable resin is cured under applied mechanical pressure.

35. The method according to any one of claims 13 to 19, wherein the curable resin is thermally decomposed by radiation curing.

36. 36. The method of claim 35, wherein the radiation curing comprises one or more of ultraviolet (UV) radiation, infrared (IR) radiation, microwave radiation, and electron beam radiation.

37. 36. The method of claim 35, wherein the radiation curing comprises microwave radiation.

38. 38. The method of claim 37, wherein the microwave radiation is generated by a variable frequency microwave generator.

39. The method of any one of claims 13 to 19, wherein the cured resin is pyrolyzed under applied mechanical pressure.

40. The method of any one of claims 13 to 19, wherein the cured resin is pyrolyzed under reduced pressure.

41. 1. An apparatus for forming a micromorphologically crack-free glassy carbon article, each having a length and width of at least 10 mm and a thickness of at least 5 mm, from a laminate stack formed from the laminated object by adding one or more sheets of morphologically crack-free glassy carbon and / or one or more additional laminates of micromorphologically crack-free glassy carbon and curing and pyrolyzing the curable and pyrolyzable resin layer therebetween, the curable and pyrolyzable resin layer comprising furfuryl alcohol and a curing catalyst, and the curable and pyrolyzable resin layer underlying each added sheet and / or added laminate, the apparatus comprising: (a) first and second sheets of micromorphologically crack-free glassy carbon as a laminated object, each having a length and width of at least 10 mm and a thickness of at least 5 mm; a reaction vessel enclosing an interior volume in which the laminated body or laminated stack is disposed; a hydraulic press drive assembly arranged to apply mechanical pressure to the laminated body or laminated stack on its outer surface; a heating assembly arranged to subject the laminated body or laminate stack to elevated temperatures for curing and pyrolysis of the one or more curable and pyrolyzable resin layers therein; An apparatus comprising:

42. 42. The apparatus of claim 41, further comprising a vacuum pump coupled to the interior volume of the reaction vessel to maintain a reduced pressure in the interior volume during curing and pyrolysis of the one or more resin layers.

43. 42. The apparatus of claim 41, wherein the heating assembly generates electromagnetic radiation effective for curing and / or pyrolysis of the curable and pyrolyzable resin.

44. 44. The apparatus of claim 43, wherein the electromagnetic radiation comprises one or more of ultraviolet (UV) radiation, infrared (IR) radiation, microwave radiation, and electron beam radiation.

45. 42. The apparatus of claim 41, wherein the heating assembly includes a variable frequency microwave oscillator.

46. 42. The apparatus of claim 41, wherein the hydraulic press drive assembly is coupled to a hydraulic press support plate at an outer surface of the laminated object or laminate stack.

47. 47. The apparatus of claim 46, wherein the hydraulic press support plate includes an internal heat exchange chamber through which a heat exchange fluid is circulated for heat exchange with the laminated body or laminated stack.

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