Thermal reactive extrusion

Abstract

An additive manufacturing device including feed lines coupled to a pumping arrangement to supply a coreactive component, wherein the coreactive components mix and react to form a coreactive composition; a mixing arrangement fluidly coupled downstream of the pumping arrangements; a print nozzle fluidly coupled downstream of the mixing arrangement; and a thermal energy source configured to supply thermal energy to at least one of the coreactive components and the coreactive composition. By supplying thermal energy to at least one of the coreactive components and the coreactive composition the printability and buildability of objects three dimensionally printed via the additive manufacturing device is improved. The coreactive composition cures under ambient conditions upon extrusion from the print nozzle.

Description

THERMAL REACTIVE EXTRUSIONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 63 / 562,300 entitled “THERMAL REACTIVE EXTRUSION”, filed on March 7, 2024, the entire disclosure of which is incorporated by reference in its entirety.GOVERNMENT LICENSE RIGHTS

[0002] This invention was made with government support under Government Contract No. W91 INF- 17-2-0027 awarded by the U.S. Army Contracting Command on behalf of the U.S. Army Research Laboratory (ARL) Additive Manufacturing. The government may have certain rights in the invention.FIELD

[0003] The present disclosure relates to an apparatus for additive manufacturing including a thermal component, and methods thereof.BACKGROUND

[0004] Ambient reactive extrusion (ARE) 3D printing may be used to form 3D objects made from a variety of different materials. During the printing of an object using a thermosetting composition, at least two coreactive components are mixed together to create a coreactive composition.

[0005] The complexity of the geometries of the desired 3D printed object may be limited by the properties of the printing material used.SUMMARY

[0006] The present disclosure provides an additive manufacturing device, including: a first feed line coupled to a first pumping arrangement, the first feed line configured to supply a first coreactive component; a second feed line coupled to a second pumping arrangement, the second feed line configured to supply a second coreactive component; a mixing arrangement fluidly coupled downstream of the first and second pumping arrangements, wherein the first coreactive component and the second coreactive components mix and react within an interiorvolume of the mixing arrangement to form a coreactive composition; a print nozzle fluidly coupled downstream of the mixing arrangement, wherein upon extrusion from the print nozzle, the coreactive composition cures under ambient conditions; and a thermal energy source configured to supply thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

[0007] The present disclosure further provides a method of three-dimensional printing using an additive manufacturing device, including: combining a first coreactive component and a second coreactive component in a mixing arrangement, the first coreactive component and the second coreactive component reacting to form a coreactive composition; supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition; extruding the coreactive composition from the mixing arrangement through a print nozzle. The thermal energy is at least one of convective thermal energy, conductive thermal energy, or radiative thermal energy.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the disclosure itself will be better understood by reference to the following description taken in conjunction with the accompanying drawings. These above-mentioned and other features of the disclosure may be used in any combination or permutation.

[0009] FIG. 1A illustrates a convection thermal additive manufacturing device of the present disclosure;

[0010] FIG. IB illustrates a second view of the convection thermal additive manufacturing device of FIG. 1A;

[0011] FIG. 2A illustrates a conduction thermal additive manufacturing device of the present disclosure;

[0012] FIG. 2B illustrates a second view of the conduction thermal additive manufacturing device of FIG. 2A;

[0013] FIG. 3A illustrates a convection and conduction thermal additive manufacturing device of the present disclosure;

[0014] FIG. 3B illustrates a second view of the convection and conduction thermal additive manufacturing device of FIG. 3A;

[0015] FIG. 4A illustrates a radiation thermal additive manufacturing device of the present disclosure including a square IR emitter;

[0016] FIG. 4B illustrates a second view of the radiation thermal additive manufacturing device of FIG. 4A;

[0017] FIG. 5A illustrates a radiation thermal additive manufacturing device of the present disclosure including a spot IR emitter;

[0018] FIG. 5B illustrates a second view of the radiation thermal additive manufacturing device of FIG. 5A;

[0019] FIG. 6 is a flow chart of a method of additive manufacturing for printing a 3D object using an additive manufacturing device;

[0020] FIG. 7 is a flow chart of the method of FIG. 6 using the additive manufacturing device of FIGS. 1 A and IB;

[0021] FIG. 8 is a flow chart of the method of FIG. 6 using the additive manufacturing device of FIGS. 2A and 2B;

[0022] FIG. 9 is a flow chart of the method of FIG. 6 using the additive manufacturing device of FIGS. 3 A and 3B;

[0023] FIG. 10 is a flow chart of the method of FIG. 6 using the additive manufacturing devices of FIG. 4A, 4B, 5A, and 5B;

[0024] FIG. 11 illustrates a conduction thermal additive manufacturing device of the present disclosure comprising a heat block and heated nozzle; and

[0025] FIG. 12 illustrates the heat block and heated nozzle of FIG. 11; and

[0026] FIG. 13 is a flow chart of the method of FIG. 6 using the additive manufacturing device of FIGS. I l and 12.

[0027] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate the disclosure, and such exemplifications are not to be construed as limiting the scope of the disclosure in any manner.DETAILED DESCRIPTION

[0028] The present disclosure provides an apparatus and method of supplying thermal energy to components of a corcactivc composition during the 3D printing process to improve printability and buildability of objects three dimensionally printed via ambient reactive extrusion. By providing thermal energy to the components during extrusion and / or thermal energy post after extrusion, such as on the build platform, 3D coreactive compositions with long gel and / or curing times may be used to build objects larger in the z-direction, in more complex geometries, and / or without the need for support materials, as compared to objects 3D printed by known technologies.

[0029] I. Definitions

[0030] For purposes of the following detailed description, it is to be understood that the disclosure may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term "about." For example, numerical ranges provided for weight percentages of components or amounts of components added should be construed as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0031] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0032] Whereas particular examples of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present disclosure may be made without departing from what is defined in the appended claims.

[0033] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of "1 to 10" is intended to include all sub-ranges from (and including) the recited minimum value of 1 to the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[0034] The use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, the use of "or" means "and / or" unless specifically stated otherwise, even though "and / or" may be explicitly used in certain instances.

[0035] “Ambient reaction extrusion” or “ARE” printing is used herein to describe 3D printing in which a coreactive composition is deposited onto a printing platform using an additive manufacturing device and cured at ambient conditions.

[0036] Providing “convection” thermal energy is used herein to describe the process of energy transfer where there is an energy transformation within a fluid, such as heating milk with steam.

[0037] Providing ‘ ‘conduction” thermal energy is used herein to describe the process of energy transfer between objects through physical contact, such as heating a pot on a flat top stove.

[0038] Providing ‘ ‘radiation” energy is used herein to describe the process of energy transfer between things without direct physical contact, such as microwaving food in a micro wave oven.

[0039] ‘Coreactive composition” refers to a composition comprising at least two different compounds capable of chemically reacting with each other to form covalent bonds.

[0040] “Coreactive component” refers to a compound containing at least one reactive functional group, that when combined with a chemically compatible functional group, react to form a coreactive composition.

[0041] “Component” refers to a composition in which the constituents of the component are not coreactive until combined and mixed with another component to form a coreactive composition.

[0042] “Ambient(ly), ’’“ambient conditions,” or “room temperature” are used herein to describes temperature values as low as 20 °C, 23 °C, or 25 °C, as high as 27 °C, 29 °C, or 30 °C, or between any of the foregoing values used as endpoints, such as between 20 °C and 30 °C , orbetween 23 °C and 27 °C; pressure values as low as 0.85 atm, 0.90 atm, or as high as 1.0 atm, 1.02 atm, or 1.05 atm, or between any of the foregoing values used as endpoints, such as between 0.85 atm and 1.05 atm, or between 0.95 atm and 1.05 atm; and relative humidity values as low as 25% RH, 35% RH or 50% RH, as high as 75% RH, 85% RH, 90% RH, or 95% RH, or between any of the foregoing values used as endpoints, such as between 25% RH and 95% RH or between 50% RH and 75% RH.

[0043] “IR” or “infrared radiation” is used herein to describe electromagnetic radiation with wavelengths from about 700 nanometers (nm) to 1 millimeter (mm). Wavelengths of IR are longer than visible light waves but shorter than radio waves.

[0044] II. Coreactive Chemistries

[0045] Additive manufacturing using coreactive compositions, also referred to as ambient reactive extrusion, or ARE type three-dimensional printing, typically utilizes at least two components that react with each other (e.g., are coreactive). A first coreactive component (sometimes referred to herein as a first reactant group, a first reactive functional group, part A) and at least one second coreactive component (sometimes referred to herein as a second reactant group, second reactive functional group, part B), when extruded in combination and / or succession, chemically react with one another to form a coreactive composition. The coreactive composition may thereafter cure under ambient conditions or, depending on the chemistry of the reaction, with the assistance of, for example, heat, actinic radiation, catalysts, addition of curing agents-post extrusion, etc. to form an object, or a portion of an object, comprising a thermosetting polymer (sometimes referred to as a thermoset), a thermoplastic polymer, or combinations thereof. At least the first coreactive component and the second coreactive component are chosen by one skilled in the art to result in the desired final product (e.g., thermoset, thermoplastic, etc.).

[0046] Three dimensional objects formed from coreactive compositions are additively manufactured by extruding the coreactive composition, which may be in an at least partially reacted state, onto a surface, such as a build platform. The coreactive composition may be in an at least partially reacted state at the time of extrusion and thereafter fully react and cure to form a layer of the coreactive composition. Successive layers of either the same, or different coreactive compositions can be deposited, forming additional layers of material. The coreactive composition may be at least partially reacted when the coreactive components come together,such as in a mixing volume, just prior to extrusion. Alternatively, the two coreactive components could be premixed before extrusion and treated in a way to arrest the reaction (c.g., arrest curing of the coreactive composition), such as freezing the mixture upon mixing.

[0047] It may be desirable to select the chemistry of each layer of the deposited coreactive composition such that covalent bonds between each successive layer of material are formed. Furthermore, different portions of the article can be printed from different coreactive compositions (e.g., a first coreactive composition printed to form a first portion of the object such as a base portion, an internal structure, etc., and a second coreactive composition printed to form a second portion of the object), and, depending on the chemical reactivity between the different coreactive compositions, covalent bonds might also form between different materials.

[0048] Specifically, an article may be printed so as to have a rigid portion and a flexible portion, a rigid portion and a foam-like portion, a tactile portion and a rigid and / or flexible portion, two portions comprising different densities, one or more conductive portions, one or more thermally / electrically conductive portions, two or more different colors, two or more different rheological profiles, two or more different materials comprising different affinities for water and / or solvent(s), and the like. The article may also be printed such that the coreactive compositions are deposited onto existing articles (e.g., other thermosets and / or thermoplastics, metals, woods, composite materials, ceramics, etc.) resulting in an article comprising both coreactive and non-coreactive compositions.

[0049] Additive manufacturing as described herein may result in an object having greater strength, particularly along the Z (e.g., vertical) axis, as compared to other extruded or printed parts due to the covalent bonding between the printed layers. Strong intralayer and interlayer covalent bonding results in not only stronger parts, but also in more uniform part geometries; that is, less print lines and / or portion differentials. The ability to form, in one process, objects having multiple substrates and / or portions comprising different coreactive or non-coreactive compositions is a further advantage.

[0050] Table 1 describes suitable coreactive compositions and the coreactive components from which they can be formed. These coreactive compositions can be printed by any of the methods described herein, either alone or in combination, to form three dimensional objects.

[0051] Another advantage of additive manufacturing using coreactive compositions may be that the coreactive compositions can be three dimensionally printed at relatively low viscosity. Therefore, relatively large amounts (e.g., high relative weight percents) of additives and / or fillers can be included with the coreactive components while maintaining a printable viscosity. Both the type and / or the amount of additives can be selected or “tuned” to result in desirable chemical and / or physical properties of the printed article. Coreactive compositions can be tuned with the addition of additives and / or fillers for desired mechanical performance (e.g., strength, elasticity, rigidity, sag resistance, etc.), surface features (e.g., hardness, texturing, smoothness, etc.), chemical resistance (e.g., solvent resistance, etc.), thermal resistance (including fire retardancy, etc.) or conductivity, and / or electrical insulation or conductivity. Coreactive compositions can also be tuned with the addition of one or more catalytic / activator / accelerant additives in any of the coreactive components to result in desirable reaction kinetics, such as rate of reaction.

[0052] Table 2 describes additives that can be included with any coreactive compositions, such as those described in Table 1. The additives can be included in, either, or both of, the first and second coreactive components (e.g., either, or both of the Part A / Part B), depending on the desired chemical and / or physical properties of the resulting object. In this case, Table 2 describes specific additives and fillers that may be suitable for ambient reactive extrusion-based three-dimensional printing, however, Table 2 is non-limiting. Therefore, other additives may be included with the coreactive composition(s), such as additives known to those skilled in the coatings, extrusion, and thermoplastic areas.

[0053] Any suitable combination of coreactive composition(s) and optionally additive(s) / filler(s), can be printed by a three-dimensional printing system adapted for mixing and extruding feedstocks. Two or more volumetric metering pumps (e.g., positive displacement pumps, progressive cavity pumps, etc.) may each respectively discharge, in combination or succession, the two coreactive components associated with a coreactive composition (e.g., the first reactive component discharged by the first metering pump and the second coreactivecomponent discharged by the second metering pump into a mixing volume). In some cases, the mixing volume can include mechanical (c.g., driven) mixing features. Upon entering the mixing volume, the first and second coreactive components begin to mix and react, and thereafter, are extruded through an extrusion print nozzle in an at least partially reacted state. Once extruded, the two coreactive components further react and cure, which, as described above, may be under ambient conditions, to form either a thermoset, a thermoplastic material, or combinations thereof.

[0054] III. Additive Manufacturing Device

[0055] An additive manufacturing device 10 may be used to print a 3D object using a coreactive composition. The additive manufacturing device 10 may be designed to hold pumping arrangements 20 that supply coreactive components used in additive manufacturing, as shown in FIGS. 1A-5B. The different coreactive components share a coreactive chemistry with each other. These coreactive components can be combined to form printable coreactive compositions. Each printable coreactive composition is made of a combination of at least two of the coreactive components. Additive manufacturing device 10 may be configured to use any of the coreactive components discussed above to print any of the coreactive compositions described in Section II.

[0056] Additive manufacturing device 10 of the present application may include at least two pumping arrangements 20, a mixing arrangement 30, a print nozzle 50, and at least one thermal energy source 60, 70, 75, 80, 90. Device 10 may include a top mount 8 that supports the at least two pumping arrangements 20 and the at least one thermal energy source 60, 70, 75, 80, 90, and removably couples additive manufacturing device 10 to a 3D printer gantry system or a robotic printing arm (not shown). The at least two pumping arrangements 20 may each be configured to dispense a coreactive component into mixing arrangement 30. The coreactive components may be mixed in mixing arrangement 30 forming a coreactive composition. The coreactive composition may be extruded from mixing arrangement 30, through print nozzle 50. Print nozzle 50 may deposit the coreactive composition such that a 3D object is formed. Each of the components that comprise additive manufacturing device 10, and methods of three- dimensional printing are discussed in more detail below.

[0057] A. Pumping Arrangements

[0058] At least two pumping arrangements 20 can be removably coupled to a mount 40 of additive manufacturing device 10 of the present disclosure. Mount 40 may be integrally coupled to top mount 8. Alternatively, mount 40 and top mount 8 may be one unitary mount. Theat least two pumping arrangements 20 may be fluidly coupled with a feed line 24 that supplies a source of a respective corcactivc component to a respective pumping arrangements 20.

[0059] Referring to FIGS. 1A-5B, each of the at least two pumping arrangements 20 include a positive displacement- type pump, such as a progressive cavity pump 22. To prevent backflow, progressive cavity pump 22 can be configured similar to a screw. Due to the design of progressive cavity pump 22, as the coreactive component is discharged, the flow can only move in the direction of discharge. Additionally, progressive cavity pump 22 can meter flow to a given volumetric dosage. Alternatively, any cartridge, pen, or other coreactive composition extruder may be used in pumping arrangement 20. As shown in FIGS. 1A-5B, additive manufacturing device 10 may include a first progressive cavity pump 22a and a second progressive cavity pump 22b, each used to pump, or otherwise supply, a different coreactive component.

[0060] B. Mixing Arrangement

[0061] Referring to FIGS. 1A-5B, a mixing arrangement for additive manufacturing device 10 is provided. Located downstream of pumping arrangements 20 within diamond mount 40, mixing arrangement 30 may comprise a mixing volume 32, at least one fluid channel fluidly connected to each of the at least two pumping arrangements 20, and a mixer. The configuration of the at least one fluid channel may be adapted to any arrangement such that the discharged coreactive compositions flow through the at least one fluid channel into mixing volume 32. Mixing volume 32 may be a cylindrical shape or any other geometry adapted for capturing discharged coreactive compositions. The geometry of mixing volume 32 may depend on the properties or volume of the discharged coreactive compositions, or available space within diamond mount 40. Mixing volume 32 may also include one or more mechanical mixing devices, such as an impeller, so that the coreactive components discharged into mixing volume 32 are mechanically (e.g., dynamically) mixed.

[0062] Additive manufacturing device 10 may hold coreactive composition within the mixing volume for a period of time. The period of time may be from 0 seconds, 1 seconds, 2 seconds, 3 seconds, to 5 seconds, 6 seconds, 7 seconds, or within any range using any two of the foregoing as endpoints, such as 0-7 seconds, 1-6 seconds, 2-5 seconds, or 3-4 seconds. Holding the coreactive composition within the mixing volume may ensure that the coreactive components are fully mixed and a homogeneous coreactive composition is created.

[0063] C. Print Nozzle

[0064] Coreactive compositions from mixing volume 32 are extruded through print nozzle 50. Print nozzle 50 may be fluidly coupled downstream of mixing volume such that the coreactive composition may be extruded through print nozzle 50. Print nozzle 50 may be a variety of shapes to facilitate the extrusion of coreactive compositions.

[0065] D. Thermal Energy Source

[0066] The compositions listed in Section II above may be extruded through print nozzle 50 onto a print bed and cured under ambient conditions to form a 3D object. Here, thermal energy of various forms (i.e., radiative, conductive, and / or convective) can be supplied to the coreactive components and / or the resulting coreactive composition prior to, during, or post extrusion. The addition of the thermal energy assists in the ambient curing process, where the thermal energy increases the reaction rate between the coreactive components, thereby lowering the gel time, tack free time, and curing time associated with the resulting coreactive composition, as compared with the same coreactive composition additively manufactured without thermal assistance. Here, since the coreactive composition sets / gels faster, the printed material provides structural support for the part more quickly, thereby enabling printing of complex geometries. Furthermore, thermally assisted ambient reactive extrusion additive manufacturing may allow for objects to be printed without the need for support materials, such as tubular objects. Moreover, thermally assisted ambient reactive extrusion additive manufacturing may result in parts printed with less stack height errors, as compared to non-thermally assisted printing.

[0067] Additive manufacturing device 10 may include at least one thermal energy source 60, 70, 75, 80, 90. Thermal energy source 60, 70, 75, 80, 90 may be used to supply various forms of thermal energy to coreactive compositions printed by additive manufacturing device 10, such the rate that the coreactive components interact / react and / or the rate that the coreactive composition reacts / cures is adjusted, resulting in higher buildability and / or beneficial performance characteristics as will be described in further detail herein. The thermal energy source 60, 70, 75, 80, 90 may be coupled to mount 40, the gantry system (not shown) that additive manufacturing device 10 is coupled to, or any other suitable coupling point that allows thermal energy source 60, 70, 75, 80, 90 to supply thermal energy to additive manufacturing device 10. Suitable thermal energy sources may comprise a heat ring 60, heated supply lines 70, heat block 75, an IR broad / short focal length IR emitter 80, an IR focused / long focal length IR emitter 90, or a combination thereof.

[0068] The thermal energy source may supply conductive thermal energy, convective thermal energy, or radiative thermal energy to at least one of the corcactivc components and / or the coreactive composition to accelerate the reaction between one or more of the coreactive components.

[0069] i. Convectively Thermally Assisted Ambient ReactiveExtrusion:

[0070] FIGS. 1A and IB illustrate additive manufacturing device 10 including thermal energy source 60 that supplies convective thermal energy to the coreactive composition as it is extruded through nozzle 50. Thermal energy source 60 comprises an air heater / blower 62 and a heat ring 64 fluidly coupled to air heater / blower 62. Heat ring 64 may include a plurality of air ports 66 configured to expel air directed at a distal end 52 of nozzle 50. The plurality of air ports 66 may be spaced around an outer circumference 65 of heat ring 64 and angled toward distal end 52 of nozzle 50.

[0071] During printing, air heater / blower 62 may heat an amount of air and force the heated air through heat ring 64. As a coreactive composition is extruded during printing, the heated air may be expelled through air ports 66 directed at the coreactive composition just as the coreactive composition extrudes from distal end 52 of nozzle 50. After being thermally assisted via convection from the heated air, the extruded coreactive composition may be deposited onto a print bed and cured under ambient conditions to form a 3D printed object. Thermal energy source 60 may supply thermal energy in predetermined intervals, or continuously during the printing of a 3D object.

[0072] ii. Conductively Thermally Assisted Ambient ReactiveExtrusion

[0073] As shown in FIGS. 2A and 2B, additive manufacturing device 10 may include thermal energy source 70 that supplies conductive thermal energy to the coreactive components as they flow through feed lines 24 into pumping arrangements 20 and / or the coreactive composition within mixing arrangement 30.

[0074] To transfer thermal energy through convection, thermal energy source 70 may comprise at least one of a heat source 72 and / or heat tape 74.

[0075] Thermal energy source 70 may include supply thermal energy to feed lines 24. Feed lines 24 may each feed a coreactive component into a respective pumping arrangement 20.Heat source 72 may be mechanically and / or fluidly coupled to feed lines 24 such that as corcactivc components flow through feed lines 24, the components pass through heat source 72 and are heated. The pre-heated coreactive components may then be extruded into the pumping arrangement 20 and subsequently printed via the 3D printing process.

[0076] Additionally or alternatively, thermal energy source 70 may include heat tape 74 applied to at least one of feed lines 24, the at least two pumping arrangements 20, mixing arrangement 30, nozzle 50, the entire outer surface of additive manufacturing device 10, any metal surface of additive manufacturing device 10, a seal of additive manufacturing device 10, and a motor of additive manufacturing device 10. Heat tape 74 may be applied by wrapping heat tape 74 around a portion of additive manufacturing device 10 or any other suitable means of coupling heat tape 74 to additive manufacturing device 10 such that heat tape 74 is in contact with the desired portion of additive manufacturing device 10. Heat tape 74 may be a flexible, flat cable designed to wrap around and / or contact a surface and supply thermal energy to the wrapped surface. Heat tape 74 may comprise a conducting wire that allows electricity to flow through the wire, heating the tape. Heat tape 74 applied to additive manufacturing device 10 may supply thermal energy to the portion of additive manufacturing device 10 in contact with heat tape 74 through conductive heat transfer.

[0077] After being heated via conductive thermal energy transfer from thermal energy source 70, heated coreactive components and / or a heated coreactive composition may be extruded from distal end 52 of print nozzle 50 to create a printed 3D object. The extruded coreactive composition may be deposited onto a print bed and cured under ambient conditions. In some cases, the thermal energy may decrease the cure time and / or increase the cure rate of the deposited coreactive composition, such that the three dimensionally printed object cures faster than non-thermally assisted three dimensional printing. Thermal energy sources 70 may supply thermal energy to the additive manufacturing device during any portion of the extrusion of a coreactive composition. Thermal source 70 may supply thermal energy in predetermined intervals, or continuously during the printing of a 3D object.

[0078] As shown in FIGS. 11 and 12, the print nozzle 50 of additively manufacturing device 10 may be conductively heated by a thermal energy source 75. Thermal energy source 75 may supply conductive thermal energy to the coreactive composition as it flows from mixing volume 32 through print nozzle 50 to be extruded. To transfer thermal energy throughconvection, thermal energy source 75 may include at least one of a heat block 76 and a heated nozzle end 78. To prevent conductive heat from thermal energy source 75 from transferring towards the proximal end of nozzle 50, a heat gap 77 may be provided. Heat gap 77 allows for thermal isolation of the proximal portion of nozzle 50 (e.g., the portion closer to mixing volume 32) from the conductive heat provided by heat block 76 and heated nozzle end 78. Here, heat gap 77 is meant to prevent the coreactive components from reacting and / or curing within the proximal portion of nozzle 50, ensuring that that nozzle 50 does not clog with coreactive components.

[0079] Heat block 76 and heated nozzle end 78 may comprise a heating element that conductively heats the coreactive composition as it leaves the mixing arrangement and is extruded through the print nozzle 50. Heat block 76 may be a block sized and shaped to enclose a portion of distal end 52 of print nozzle 50. Heat block 76 may comprise a heating element that conductively transfers heat to the enclosed portion of distal end 52.

[0080] Heated nozzle end 78 may be a heated tip that is coupled to a tip (the furthest most point of distal end 52 of print nozzle 50) of the print nozzle 50. Similar to heat block 76, heated nozzle end 78 may heat the coreactive composition just prior to being extruded through print nozzle 50.

[0081] Thermal energy source 75 may be used alone on additive manufacturing device 10 or in conjunction with any other conductive, convective, or radiative thermal energy source disclosed in the present description. After being heated via conductive thermal energy transfer from thermal energy source 70, the heated coreactive composition may be extruded through print nozzle 50 to create a printed 3D object. The extruded coreactive composition may be deposited onto a print bed and cured under ambient conditions. In some cases, the thermal energy may decrease the cure time and / or increase the cure rate of the deposited coreactive composition, such that the three dimensionally printed object cures faster than non-thermally assisted three- dimensional printing. Thermal energy source 75 may supply thermal energy to the additive manufacturing device during any portion of the extrusion of a coreactive composition. Thermal source 75 may supply thermal energy in predetermined intervals, or continuously during the printing of a 3D object.

[0082] iii. Convectively and Conductively Thermally AssistedAmbient Reactive Extrusion

[0083] In some cases, additive manufacturing device 10 may comprise both thermal energy source 60 and thermal energy source 70. As shown in FIGS. 3A and 3B, the corcactivc components and / or the coreactive composition may be heated through both convective and conductive thermal energy / heat transfer, as described above in sections i and ii. Combined convective and conductive thermal energy transfer may be used in conjunction and / or subsequent to one another to lower the curing time associated with printing the three dimensional objected as compared to any one of non-thermally assisted 3D printing and / or individual conductive and / or convectively thermally assisted 3D printing.

[0084] iv. Radiatively Thermally Assisted Ambient ReactiveExtrusion

[0085] As shown in FIGS. 4 and 5, Additive manufacturing device 10 may comprise a thermal energy source 80, 90 that supplies radiative thermal energy to heat at least one of the coreactive components and / or coreactive composition. In this case, the coreactive composition may be heated by exposing the composition to infrared radiation (IR) via an IR emitter. The IR radiation may accelerate the reaction / interaction between the coreactive components and / or coreactive composition, causing the coreactive components to interact and / or react more rapidly, and / or coreactive composition to cure more rapidly under ambient conditions

[0086] As shown in FIGS. 4A-B and 5A-B the thermal energy source 80, 90 may comprise an IR emitter coupled to mount 40 of additive manufacturing device 10. Suitable IR emitters may comprise a broad / short focal length IR emitter 82, a focused / long focal length IR emitter 92, or a combination thereof. The IR emitter 82 / 92 may supply radiative thermal energy via infrared light. The IR light may be of the electromagnetic radiation spectrum with wavelengths between 780 nm and 1 mm. For instance, the IR light can be categorized as IR-A (780 nm-1.4 pm), IR-B (1.4-3 pm) and / or IR-C (3 pm-1 mm). Here, the IR light utilized in the present invention is fundamentally dissimilar from ultraviolet light (UV), firstly by the difference in wavelengths (e.g., UV being shorter than IR) and secondly, by the energy flux supplied to the printed material (e.g., UV having ae high energy flux than IR). Accordingly, thermal assistance supplied by IR light is fundamentally dissimilar to traditional UV curing of coreactive compositions.

[0087] a. Broad IR Emitter

[0088] Referencing FIGS. 4A and 4B, thermal energy source 80 comprises a broad IR emitter 82. Broad IR emitter 82 may emit a beam of infrared radiation 84 toward a surface. The surface may be at least one of a print bed or other surface where the coreactive composition is being printed / extruded onto, print nozzle 50, the feed lines (similar to feed lines 24 in FIGS. 2A and 2B), mixing arrangement 30, pumping arrangements 20, or any suitable portion of additive manufacturing device 10. The beam 84 is directed at least one of the surfaces mentioned previously such that at the point in which beam 84 contacts the surface, beam 84 may comprise a beam width from 11 mm, 50 mm, 100 mm to 500 mm, 750 mm, 100 mm, or any range using any of the foregoing values as endpoints, such as 11 mm to 500 mm, 50 mm to 750 mm, or 100 mm to 500 mm.

[0089] Width 85 allows the IR light of beam 84 to contact a portion of and / or substantially all of the area that the coreactive composition is printing onto for a period of time immediately following extruding the coreactive composition from nozzle 50. The recently extruded coreactive composition may be exposed to beam 84 of IR light for 0.5 sec., 1.0 sec., 10 sec, 100 sec. to 500 sec., 1000 sec., 25400 sec., 3600 sec., or any range using any of the foregoing values as endpoints, such as 0.5 sec. to 3600 sec., 1 sec. to 2400 sec., 10 sec. to 1000 sec., or 100 sec. to 500 sec.. Additionally or alternatively, the recently extruded coreactive composition may be intermittently exposed to beam 84 of IR light. Broad IR emitter 82 may be activated (e.g., turned on) and deactivated (e.g., turned off) at varying intervals based upon controlling the amount of time the coreactive composition is exposed to IR light / radiate thermal energy during the printing of a 3D object. For instance, if a portion of the 3D printed object requires the coreactive composition to have a faster gel / cure time, broad IR emitter 82 may emit beam 84 for longer periods of time and / or continuously, therefore accelerating the reaction time of the coreactive composition being extruded. Additionally or alternatively, if a portion of a 3D printed object requires the coreactive composition to have a slow gel / cure time, broad IR emitter 82 may emit beam 84 in short segments / time intervals (e.g., discontinuously) during the printing process, allowing the coreactive composition to gel / cure more slowly, and therefore remain tacky and / or flowable during the curing process.

[0090] b. Focused IR Emitter

[0091] Referencing FIGS. 5A and 5B, thermal energy source 90 comprises a focused IR emitter 92. Focused / long focal length IR emitter 92 may emit a beam 94 of focused infraredradiation (e.g., IR light) channeled through a tube 96 directed at nozzle 50. Beam 94 may be directed at nozzle 50 such that beam 94 contacts the corcactivc composition at the point where the coreactive composition leaves distal end 52 of nozzle 50. The beam 94 may comprise a beam width from 1 mm, 2 mm, 4 mm to 6 mm, 8 mm, 10 mm, or any range using any of the foregoing values as endpoints, such as 1 mm to 10 mm, 2 mm to 8 mm, or 4 mm to 6 mm.

[0092] Extruded coreactive composition may be exposed to beam 94 of IR light for 0.5 sec., 1.0 sec., 10 sec., 100 sec. to 500 sec., 1000 sec., 1200 sec., 1800 sec., or any range using any of the foregoing values as endpoints, such as 0.5 sec. to 1800 sec., 1 sec. to 1200 sec., 10 sec. to 1000 sec., or 100 sec. to 500 sec.. Further, extruded coreactive composition may be intermittently exposed to beam 94 of IR light. For instance, focused IR emitter 92 may be turned on and off at varying intervals to control the amount of time the coreactive composition is exposed to IR light during the printing of a 3D object. For instance, if a portion of a 3D printed object requires the coreactive composition to have a faster gel / cure time, focused IR emitter 92 may emit beam 94 for longer periods of time and / or continuously to accelerate the reaction time of the coreactive composition being extruded. Conversely, if a portion of a 3D printed object requires the coreactive composition to have a longer gel / cure time, focused IR emitter 92 may emit beam 94 in short segments / intervals during the printing process (e.g., discontinuously) to allow the coreactive composition to gel / cure more slowly, and therefore remain tacky and / or flowable during the curing process.

[0093] IV. Method of Printing:

[0094] The additive manufacturing device may be used as described above in conjunction with at least one of a convective, a conductive, or a radiative thermal energy source.

[0095] Referring to FIG. 6, a method of additive manufacturing is shown for printing a 3D object using the additive manufacturing device 10. Method 100 comprises two supplying steps 102a, 102b, a combining step 104, an extruding step 106, and a depositing step 108.

[0096] In a first supplying step 102a, a first coreactive component is supplied to device 10 via a first feedline. The first coreactive component may be supplied via a feedline into the pumping arrangement and / or into the mixing arrangement of device 10. Second supplying step 102b may supply a second coreactive component to device 10 via a second supply line.

[0097] In combining step 104, the first coreactive component and the second coreactive component are combined in the mixing arrangement of device 10. The coreactive componentsmay be any of the coreactive components mentioned in section II above. Prior to combination, the first and second corcactivc components may be held in corresponding pumping arrangements of an additive manufacturing device. To combine the first and second coreactive components, the components may be added to a mixing arrangement and mixed, either statically, or mechanically (e.g., with an impeller). Once combined, the first and second coreactive components may react to form a coreactive composition. The mixing parameters such as time spent mixing, mixing speed, mixing device, temperature, and / or pressure may vary depending on operating parameters or desired product parameters such as the amount and type of coreactive components used, the volume of components in the mixture, desired properties of the printable composition, desired properties of the printed object, and any combination of the foregoing. The coreactive composition may be any of the coreactive compositions mentioned in section II above.

[0098] Extruding step 106 comprises extruding the coreactive composition from the mixing arrangement through a print nozzle (element 50 in FIGS. 1A-5B). The extruded coreactive composition may then be deposited onto a print surface to form a 3D object, step 108. The printing surface may be a printing bed or any other material. The speed of extruding the coreactive composition from the mixing arrangement may vary depending on the properties of the coreactive composition.

[0099] During the supplying 102a / 102b, combining 104, extruding 106, or depositing 108 step of printing an object, a thermal energy source may be used to supply thermal energy to either the coreactive components and / or coreactive composition.

[0100] A. Convective Thermal Energy

[0101] To supply convective thermal energy, thermal energy may be transferred during extrusion of the coreactive composition in step 106, before depositing the coreactive composition in step 108.

[0102] As shown in FIG. 7, method 100 may include supplying thermal energy via a convective thermal energy source 200 during extruding the first coreactive composition from the mixing arrangement 106. Convective thermal energy may be supplied via heated / hot air, or any other suitable fluid source, blown at the distal end of the print nozzle while the coreactive composition is being extruded.

[0103] By supplying convective thermal energy during extrusion, the viscosity of coreactive composition may be controlled such that complex geometries are able to be createdwith minimal or no support structures, due to coreactive composition reacting more rapidly, and resulting in less drooping and sagging of the deposited composition. Further, after extrusion and supplying of convective thermal energy, the coreactive composition may experience faster cure times upon depositing the coreactive composition on the print surface.

[0104] B. Conductive Thermal Energy

[0105] Conductive thermal energy may be provided to method 100 at a variety of different junctions. As shown in FIG. 8, conductive thermal energy may be supplied directly to the first and second coreactive feed lines. In steps 300a and 300b, a conductive thermal energy source supplies thermal energy to at least one of the first and second feedlines prior to the first and second coreactive components combining in step 104. Suitable conductive thermal energy sources used in steps 300a and 300b may include heat tape or any other suitable conductive thermal energy device coupled to the first and second feed lines. Conductive thermal energy may be supplied to only the first feed line (step 300a), only the second feed line (step 300b), or a combination of both the first and second feed line (both steps 300a and 300b).

[0106] Further, conductive thermal energy may be supplied to the combination of the first and second coreactive composition. Once the first and second coreactive components are supplied (steps 102a, 102b) to the mixing arrangement, during the combination of the first and second coreactive components a conductive thermal energy source may supply thermal energy, step 300c. The conductive thermal energy source of step 300c may comprise heat tape or any other suitable conductive thermal energy source coupled to the mixing arrangement of device 10. Step 300c may be performed during method 100 alone or in combination with steps 300a and 300b.

[0107] Another suitable method of supplying conductive thermal energy is shown in FIG. 13. Method 100 may include supplying thermal energy via a conductive thermal energy source 500 directly to a portion of the print nozzle before extruding the coreactive composition from the print nozzle 107. Conductive thermal energy may be supplied via a heat block, a heated nozzle tip, or any other suitable conductive thermal energy source at the distal end of the print nozzle while the coreactive composition is being extruded. The method of supplying conductive thermal energy with a heat block / heated nozzle tip to the coreactive composition, as shown in FIG. 13, may be combined with the methods of providing conductive, convective, conductive and convective, and radiative thermal energy as shown in FIGS. 7-10.

[0108] By supplying conductive thermal energy to the coreactive components and / or corcactivc composition prior to extrusion as shown in FIGS. 8 and 13, the corcactivc components may react at an increased rate as compared to without conductive thermal energy. The increased reaction rate may cause the coreactive composition to cure faster during extrusion and deposition. A faster cure rate, and may allow for printing of more complex geometries with fewer support structures.

[0109] C. Combination of Conductive and Convective Thermal Energy

[0110] As shown in FIG. 9, method 100 may be supplied with thermal energy via a convective thermal energy source 200 and conductive thermal energy sources 300a, 300b, 300c. Both convective and conductive thermal energy may be simultaneously supplied to the additive manufacturing device during printing as described above. Additionally or alternatively, convective thermal energy may be supplied first, and then conductive thermal energy thereafter, and vice versa (e.g., discontinuously). The use of both conductive and convective thermal energy may increase the rate of reaction of the coreactive components, and therefore result in a lower cure time of the coreactive composition, as compared to either conductive or convective thermal energy assistance alone.

[0111] D. Radiative Thermal Energy

[0112] Referring to FIG. 10, a radiative thermal energy source may supply radiative thermal energy 400a, 400b during method 100. A suitable radiative thermal energy source may be an IR emitter.

[0113] Radiative thermal energy may be provided by a radiative thermal energy source during extrusion of the coreactive composition, step 400a. A focused / long focal length IR emitter may provide radiative thermal energy to the coreactive composition as it is extruded out of the print nozzle. The focused / long focal length IR emitter may direct IR light directly at the distal end of the print nozzle to supply radiative thermal energy to the extruding coreactive composition.

[0114] Additionally or alternatively to step 400a, in step 400b, a broad / short focal length IR emitter may supply thermal energy during or after deposition of the coreactive composition in step 108. Supplying radiative thermal energy in step 400b may include exposing a larger (broader) area to IR light using the broad / short focal length IR emitter.

[0115] Exposure to the radiative thermal energy may increase the cure time of the corcactivc composition. By supplying radiative energy in steps 400a, 400b, the reaction rate of the coreactive composition may be controlled such that complex geometries are able to be created with minimal support structures.ASPECTS

[0116] Aspect 1 is an additive manufacturing device, comprising: a first feed line coupled to a first pumping arrangement, the first feed line configured to supply a first coreactive component; a second feed line coupled to a second pumping arrangement, the second feed line configured to supply a second coreactive component; a mixing arrangement fluidly coupled downstream of the first and second pumping arrangements, wherein the first coreactive component and the second coreactive components mix and react within an interior volume of the mixing arrangement to form a coreactive composition; a print nozzle fluidly coupled downstream of the mixing arrangement, wherein upon extrusion from the print nozzle, the coreactive composition cures under ambient conditions; and a thermal energy source configured to supply thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

[0117] Aspect 2 is the additive manufacturing device of Aspect 1, wherein the thermal energy source comprises a conductive thermal energy source mechanically coupled to portion of the additive manufacturing device.

[0118] Aspect 3 is the additive manufacturing device of Aspect 2, wherein the conductive thermal energy source is mechanically coupled to the at least two feed lines, wherein the conductive thermal energy source supplies conductive thermal energy to the first coreactive component and the second coreactive component contained within the feed lines.

[0119] Aspect 4 is the additive manufacturing device of Aspect 2 or Aspect 3, wherein the conductive thermal energy source comprises heat tape, the heat tape in contact with at least one of the at least two pumping arrangements, the mixing arrangement, and the print nozzle, such that the heat tape supplies conductive thermal energy to the coreactive components.

[0120] Aspect 5 is the additive manufacturing device of Aspect 2, wherein the conductive thermal energy source is at least one of a heated block and a heated nozzle tipcoupled to the print nozzle such that the at least one of the heated block and the heated nozzle tip transfers thermal energy to the corcactivc composition.

[0121] Aspect 6 is the additive manufacturing device of Aspect 1, wherein the thermal energy source comprises a convective thermal energy source comprising an air source and a heat ring fluidly coupled to the air source, the heat ring including an outer circumference.

[0122] Aspect 7 is the additive manufacturing device of Aspect 6, wherein the heat ring comprises a plurality of air ports, the plurality of air ports being spaced around the outer circumference of the heat ring and angled toward a distal end of the print nozzle; and wherein the air source supplies hot air to the heat ring, such that the hot air is expelled through the plurality of air ports directed at the distal end of the print nozzle to heat the coreactive composition extruded through the print nozzle.

[0123] Aspect 8 is the additive manufacturing device of any one of Aspects 2-4, further comprising a second thermal energy source comprising a convective thermal energy source.

[0124] Aspect 9 is the additive manufacturing device of Aspect 8, wherein the conductive thermal energy source comprises heat tape, the heat tape in contact with at least one of the at least two pumping arrangements, the mixing arrangement, and the print nozzle, such that the heat tape supplies conductive thermal energy to the coreactive components; and wherein the second thermal energy source comprises a convective thermal energy source comprising an air source and a heat ring fluidly coupled to the air source, the heat ring including an outer circumference.

[0125] Aspect 10 is the additive manufacturing device of Aspect 1, wherein the thermal energy source comprises a radiative thermal energy source comprising an Infrared (IR) radiation emitter.

[0126] Aspect 11 is the additive manufacturing device of Aspect 10, wherein the IR radiation emitter comprises a broad emitter that emits a beam of IR light directed at a print surface adjacent to the print nozzle; and wherein the beam of IR light has a beam width from 10 mm to 1000 mm at a point where the beam contacts the print surface.

[0127] Aspect 12 is the additive manufacturing device of Aspect 10, wherein the IR radiation emitter comprises a focused emitter, wherein a beam of IR light is directed down a tube, the tube configured to direct the beam of IR light at a distal end of the print nozzle suchthat the beam of IR light irradiates a coreactive composition extruded through the distal end of the print nozzle.

[0128] Aspect 13 is the additive manufacturing device of any one of Aspects 1-12, wherein the thermal energy source provides thermal energy intermittently.

[0129] Aspect 14 is the additive manufacturing device of any one of Aspects 1-12, wherein the thermal energy source provides thermal energy continuously.

[0130] Aspect 15 is a method of three-dimensional printing using an additive manufacturing device, comprising: combining a first coreactive component and a second coreactive component in a mixing arrangement, the first coreactive component and the second coreactive component reacting to form a coreactive composition; supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition; wherein the thermal energy is at least one of convective thermal energy, conductive thermal energy, or radiative thermal energy; and extruding the coreactive composition from the mixing arrangement through a print nozzle.

[0131] Aspect 16 is the method of Aspect 15, wherein, when the thermal energy is convective thermal energy, the supplying of the convective thermal energy comprises directing heated air via a heat ring towards the coreactive composition as the coreactive composition is extruded through the print nozzle.

[0132] Aspect 17 is the method of Aspect 15, wherein, when the thermal energy is conductive thermal energy, the supplying of the conductive thermal energy comprises at least one of: heat tape mechanically coupled with a portion of the additive manufacturing device; a heat block coupled to a portion of the print nozzle; a heated nozzle coupled to a distal end of the print nozzle.

[0133] Aspect 18 is the method of Aspect 17, wherein when the thermal energy is radiative thermal energy, and wherein the supplying of the radiative thermal energy comprises at least one of: emitting a beam of IR light at a print surface directly adjacent to the additive manufacturing device such that the beam of IR light heats the coreactive composition; and emitting a beam of IR light directed a distal end of a print nozzle of the additive manufacturing device such that the beam of IR light heats at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

[0134] Aspect 19 is the method of any one of Aspects 15-18, wherein supplying thermal energy comprises intermittently supplying thermal energy to at least one of the first corcactivc component, the second coreactive component, and the coreactive composition.

[0135] Aspect 20 is the method of any one of Aspects 15-19, wherein supplying thermal energy comprises continuously supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

[0136] Aspect 21 is an article manufactured according to the method of any one of aspects 15 through 20.

[0137] Aspect 22 is an article manufactured by the additive manufacturing device of any one of Aspects 1 through 14.Aspect 23 is an additive manufacturing device operable to perform the method of any one of aspects 15 through 20.EXAMPLES

[0138] Aspects of the present disclosure are further illustrated by reference to the following examples. It will be apparent to those skilled in the art that many modifications, both to materials, and methods, may be practiced without departing from the scope of the disclosure.Example 1Polyurethane

[0139] A 2k polyurethane formulation incorporating additives and rheology modifiers was 3D printed at ambient conditions and with a thermal energy source set to 100°C (i.e. IR Emitter, Heat Ring, Heated extruder, and a combination of a Heat Ring and a Heated Extruder). The polyol and the isocyanate components of the polyurethane formulation were formulated using the compositions below.

[0140] The polyol and isocyanate components of the polyurethane formulation were comprised using the commercial sealant described below. From Table 1 the polyol resin mixture and the isocyanate resin mixture were weighed in a Max 300 L Flacktek DAC cup and dispensed via standard Speedmixer procedure. Table 1: Polyurethane Formulation1Total seal 6015 1 / 2 A Pack, polyol component, commercially available from PPG Industries2Total seal 6015 1 / 2 B Pack, isocyanate component, commercially available from PPG Industries

[0141] The polyol and isocyanate formulations for the polyurethane were transferred from the DAC cup to a 32oz cartridge via Flacktek SpeedDisc for optimal 3D printing by extrusion via ViscoTec 2k extruders mounted to a gantry such as the Cosine 3D printer. The gantry also supported a thermal energy source directed towards the nozzle tip.

[0142] The amount of the polyol component in the polyurethane corcactivc composition may be from 30 wt. %, 35 wt. %, or 40 wt. % to 45 wt. %, 50 wt. %, or 55 wt. %, or any range using any two of the foregoing values, such as 30 wt. % to 55 wt. %, 35 wt. % to 50 wt. %, or 40 wt. % to 45 wt. %, based on the total weight of the coreactive composition. The amount of isocyanate component in the polyurethane coreactive composition may be from 45 wt. %, 50 wt. %, or 55 wt. % to 60 wt. %, 65 wt. %, or 70 wt. %, or any range using any two of the foregoing values, such as 45 wt. % to 70 wt. %, 50 wt. % to 65 wt. %, or 55 wt. % to 60 wt. %, based on the total weight of the coreactive composition.

[0143] The polyol and isocyanate formulations were printed at print parameters listed in Table 2. The polyurethane formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a layer time of 3.2 minutes at ambient conditions and at 100 °C using various heating technologies (i.e. IR Emitter, Heat Ring, Heated extruder, and a combination of a Heat Ring and a Heated Extruder).Table 2: Printing Parameters for Polyurethane at Ambient Conditions and 100°C

[0144] The performance of the heating technologies on the buildability of the polyurethane formulation was measured in terms of the percent error of a printed stack of layers versus a modeled stack of layers. Table 3 depicts the relevant data.Table 3: Results of Polyurethane Formulations Printed at Ambient Conditions and at 100°CExample 2Epoxy-Amine

[0145] A 2k epoxy-amine formulation incorporating additives and rheology modifiers was 3D printed at ambient conditions and with an IR Emitter (a broad / short focal length IR emitter, a focused / long focal length IR emitter, or a combination thereof) set to 180 °C. The epoxy and the amine components of the formulation were formulated using the compositions below.

[0146] The epoxy component of the epoxy-amine composition was made according to the formulation in Table 4.

[0147] From Table 4, epoxy resins and rheology modifier(s) were weighed in a Max 300 L Flacktek DAC cup and dispersed via standard Speedmixer procedure.Table 4: Epoxy Component1Difunctional Epoxy resin, Eponex 1510, commercially available from Westlake Epoxy2Rheology Modifier, Cabosil TS-720, commercially available from Cabot Corp.

[0148] The amine component of the epoxy-amine composition was made according to the formulation in Table 5.

[0149] From Table 5, the amine resin and rheology modifier(s) were weighed in a Max 300L Flacktek DAC cup and dispersed via standard Spccdmixcr procedure.Table 5: Amine Component1Trifunctional Amine. Jefffamine T403. commercially available from Hunstman Corp2Rheology Modifier, Cahosil TS-720, commercially available from Cabot Corp.

[0150] The Epoxy and Amine formulations for the Epoxy- Amine formulation were transferred from the DAC cup to a 32oz cartridge via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruders mounted to a gantry such as the Cosine 3D printer. The gantry also supported a thermal energy source directed towards the nozzle tip.

[0151] The amount of the epoxy component in the epoxy-amine coreactive composition may be from 70 wt. %, 72 wt. %, or 74 wt. % to 76 wt. %, 78 wt. %, or 80 wt. %, or any range using any two of the foregoing values, such as 70 wt. % to 80 wt. %, 72 wt. % to 78 wt. %, or 74 wt. % to 76 wt. %, based on the total weight of the coreactive composition. The amount of amine component in the epoxy-amine coreactive composition may be from 20 wt. %, 22 wt. %, or 24 wt. % to 26 wt. %, 28 wt. %, or 30 wt. %, or any range using any two of the foregoing values, such as 20 wt. % to 30 wt. %, 22 wt. % to 28 wt. %, or 24 wt. % to 26 wt. %, based on the total weight of the coreactive composition.

[0152] The formulations were printed at print parameters listed in Table 6. The epoxyamine formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a layer time of 6.4 minutes at ambient conditions and at 180 °C using 2 different IR emitters (i.e. broad / short focal length IR emitter and a focused / long focal length IR emitter).Table 6: Print Parameters for Epoxy-Amine Formulations at Ambient Conditions and 100°C

[0153] The performance of the thermal energy source on the buildability of the EpoxyAmine formulation was measured in terms of the percent error of a printed stack of layers versus a modeled stack of layers. Table 7 depicts the relevant data.Example 3Aza-Michael Addition

[0154] A 2k Aza-Michael addition formulation incorporating additives and rheology modifiers was 3D printed at ambient conditions and with a heat ring set to 100 °C. The acrylate and the amine components of the Aza-Michael addition formulation were formulated using the compositions below.

[0155] The amine component of the Aza-Michael addition composition was made according to the formulation in Table 8.

[0156] From Table 8, amine resins and rheology modifier(s) were weighed in a Max 300 L Flacktek DAC cup and dispersed via standard Speedmixer procedure.Table 8: Amine Component Formulation1Monofunctional Amine Resin, Aminopropyldiethanolamine, commercially available from Sigma Aldrich2Difunctional Amine Resin, Jefffamine ED 900, commercially available from Hunstman Corp3Trifunctional Amine Resin, Jefffamine T403, commercially available from Hunstman Corp4Rheology Modifier, Cabosil TS-720, commercially available from Cabot Corp.

[0157] The acrylate component of the Aza-Michael addition composition was made according to the formulation in Table 9.

[0158] From Table 9, the acrylate resins, radical inhibitor, and rheology modifier(s) were weighed in a Max 300L Flacktek DAC cup and dispersed via standard Speedmixer procedure. Table 9: Acrylate Component Formulation1Diacrylate Resin, Miramer Polyethylene 600 Diacrylate M286, commercially available from Miwon2Hexaacrylate Resin, Miramer Dipentaerthritol Hexacrylate M600, commercially available from Miwon3Radical inhibitor, MEHQ inhibitor, commercially available from Sigma- Aldrich4Rheology Modifier, Cabosil TS-720, commercially available from Cabot Corp.

[0159] The amine and acrylate formulations for the formulation were transferred from the DAC cup to a 32oz cartridge via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruders mounted to a gantry such as the Cosine 3D printer. The gantry also supported a thermal energy source directed towards the nozzle tip.

[0160] The amount of the amine component in the Aza-Michael coreactive composition may be from 55 wt. %, 59 wt. %, or 61 wt. % to 65 wt. %, 67 wt. %, or 70 wt. %, or any range using any two of the foregoing values, such as 55 wt. % to 70 wt. %, 59 wt. % to 67 wt. %, or 61 wt. % to 65 wt. %, based on the total weight of the coreactive composition. The amount of acrylate component in the Aza-Michael coreactive composition may be from 30 wt. %, 34 wt. %, or 36 wt. % to 38 wt. %, 40 wt. %, or 45 wt. %, or any range using any two of the foregoing values, such as 30 wt. % to 45 wt. %, 34 wt. % to 40 wt. %, or 36 wt. % to 38 wt. %, based on the total weight of the coreactive composition.

[0161] The amine and acrylate formulations were printed at print parameters listed in Table 10.

[0162] The Aza-Michael Addition formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a layer time of 1.2 minutes at ambient conditions and at 100 °C using a Heat Ring.Table 10: Print Parameters for Aza-Michael Addition Formulation at Ambient Conditions and 100°C

[0163] The performance of the heating technologies on the buildability of the formulation was measured in terms of the percent error of a printed stack of layers versus a modeled stack of layers. Table 11 depicts the relevant data.Table 11: Results of Aza-Michael Addition Formulations Printed at Ambient Conditions and at100°C with a Heat RingExample 4 Polyurea

[0164] A 2k Polyurea formulation incorporating additives and rheology modifiers was 3D printed at ambient conditions and with a heat ring set to 100 °C. The isocyanate and the amine components of the polyurea composition were formulated using the compositions below.

[0165] The isocyanate-side composition of the formulation was made from the components in Table 12.

[0166] From Table 12, isocyanate resins and rheology modifier(s) were weighed in a Max 300 L Flacktek DAC cup and dispersed via standard Spccdmixcr procedure.Table 12: Isocyanate Component1Trifunctional Isocyanate Resin, Desmodur N3900, commercially available from Covestro2Rheology Modifier, Cabosil TS-720, commercially available from Cabot Corp.

[0167] The amine-side composition of the formulation was made from the components of Table 13.

[0168] From Table 13, the amine resins and rheology modifier(s) were weighed in a Max 300L Flacktek DAC cup and dispersed via standard Speedmixer procedure.Table 13: Amine Component1Difunctional Resin, Desmosphen 1420, commercially available from Covestro2Rheology Modifier, Cabosil TS-720, commercially available from Cabot Corp.

[0169] The amine and isocyanate formulations for the formulation were transferred from the DAC cup to a 32oz cartridge via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruders mounted to a gantry such as the Cosine 3D printer. The gantry also supported a thermal energy source directed towards the nozzle tip.

[0170] The amount of the isocyanate component in the polyurea coreactive composition may be from 30 wt. %, 32 wt. %, or 34 wt. % to 36 wt. %, 38 wt. %, or 40 wt. %, or any range using any two of the foregoing values, such as 30 wt. % to 40 wt. %, 32 wt. % to 38 wt. %, or 34 wt. % to 36 wt. %, based on the total weight of the coreactive composition. The amount of amine component in the polyurea coreactive composition may be from 60 wt. %, 62 wt. %, or 64 wt. % to 66 wt. %, 68 wt. %, or 70 wt. %, or any range using any two of the foregoing values, such as 60 wt. % to 70 wt. %, 62 wt. % to 64 wt. %, or 66 wt. % to 68 wt. %, based on the total weight of the coreactive composition.

[0171] The amine and isocyanate formulations were printed at print parameters listed in Table 14.

[0172] The Polyurea formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a layer time of 1.2 minutes at ambient conditions and at 100 °C using a Heat Ring.Table 14: Print Parameters for Poly urea Composition at Ambient Conditions and IQOoC

[0173] The performance of the thermal energy source on the buildability of the formulation was measured in terms of the percent error of a printed stack of layers versus a modeled stack of layers. Table 15 depicts the relevant data.Table 15: Results of Polyurea Formulations Printed at Ambient Conditions and at 100 °C with aExample 5Polythioether

[0174] A 2k polythioether formulation incorporating additives and rheology modifiers was 3D printed at ambient and with a heat ring set to 110°C. The epoxy and thiol components of the polythioether were formulated using the composition below.

[0175] The epoxy and thiol components of the polythioether formulation were comprised using the commercial sealant described below. From Table 16 the epoxy resin mixture and thethiol resin mixture were weighed in a Max 300 L Flacktek DAC cup and dispensed via standard Spccdmixcr procedure.1PR2001 A Pack, poly thioether sealant, commercially available from PPG Industries2PR2001 B Pack, poly thioether sealant, commercially available from PPG Industries

[0176] The thiol and epoxy formulations were transferred from the DAC cup to 12oz cartridges via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruder mounted to a gantry such as Cosine 3D printer.

[0177] The amount of the epoxy component in the polythioether coreactive composition may be from 10 wt. %, 12 wt. %, or 15 wt. % to 18 wt. %, 20 wt. %, or 25 wt. %, or any range using any two of the foregoing values, such as 10 wt. % to 25 wt. %, 12 wt. % to 10 wt. %, or 15 wt. % to 18 wt. %, based on the total weight of the coreactive composition. The amount of thiol component in the poly thioether coreactive composition may be from 75 wt. %, 77 wt. %, or 80 wt. % to 85 wt. %, 87 wt. %, or 90 wt. %, or any range using any two of the foregoing values, such as 75 wt. % to 90 wt. %, 77 wt. % to 87 wt. %, or 80 wt. % to 85 wt. %, based on the total weight of the coreactive composition.

[0178] The gantry also supports a thermal energy source directed towards the nozzle tip. The thiol and epoxy formulations are printed at print parameters listed in Table 17.Table 17: Print Parameters

[0179] The polythioether formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a consistent layer time at ambient conditions and at 110°C using a heat ring.The resolution and buildability of the material printed at 110°C using a heat ring was measured to be better than ambient conditions. Table 18 depicts the relevant open time of the material data with the addition of heat.Table 18: Performance ResultsExample 6 Polysulfide

[0180] A 2k polysulfide formulation incorporating additives and rheology modifiers was 3D printed at ambient and with a heat ring set to 130°C. The two pail, manganese dioxide polysulfide compounds, was formulated using the composition below.

[0181] The polysulfide formulation was comprised using the commercial sealant described below. From Table 19 the manganese dioxide and polysulfide compounds were weighed in a Max 300 L Flacktek DAC cup and dispensed via standard Speedmixer procedure.1PR 1440 A Pack, polysulfide sealant, commercially available from PPG Industries2PR1440 B Pack, polysulfide sealant, commercially available from PPG Industries

[0182] The polysulfide formulations were transferred from the DAC cup to 12oz cartridges via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruder mounted to a gantry such as Cosine 3D printer.

[0183] The amount of the manganese dioxide component in the polysulfide coreactive composition may be from 5 wt. %, 10 wt. %, or 15 wt. % to 20 wt. %, 22 wt. %, or 25 wt. %, orany range using any two of the foregoing values, such as 5 wt. % to 25 wt. %, 10 wt. % to 22 wt. %, or 15 wt. % to 20 wt. %, based on the total weight of the corcactivc composition. The amount of polysulfide component in the polysulfide coreactive composition may be from 75 wt. %, 80 wt. %, or 85 wt. % to 90 wt. %, 92 wt. %, or 95 wt. %, or any range using any two of the foregoing values, such as 75 wt. % to 95 wt. %, 80 wt. % to 92 wt. %, or 85 wt. % to 90 wt. %, based on the total weight of the coreactive composition.

[0184] The gantry also supports a thermal energy source directed towards the nozzle tip. The polysulfide formulations are printed at print parameters listed in Table 20.Table 20: Print Parameters

[0185] The polysulfide formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a consistent layer time at ambient conditions and at 130°C using a heat ring. The resolution and buildability of the material printed at 130°C using a heat ring was measured to be better than ambient conditions. Table 21 depicts the relevant open time of the material data with the addition of heat.Table 21: Performance ResultsExample 7Addition-Cured Silicone

[0186] A 2k addition-cured silicone formulation incorporating additives and rheology modifiers is 3D printed at ambient conditions and with a heat ring set to 150 °C. The additioncured silicone formulation was comprised using the commercial adhesive described below. From Table 22 the hydride-functional and vinyl functional silicone compounds were weighed in a Max 300 L Flacktek DAC cup and dispensed via standard Speedmixer procedure.Table 22: Commercial Addition Cured Composition1RTV630 A Pack, beige silicone, commercially available from Momentive2RTV630 B Pack, blue silicone, commercially available from Momentive

[0187] The hydride functional siloxane and vinyl functional PDMS formulations for the formulation are transferred from the DAC cup to a 32oz cartridge via Flacktek SpeedDisc for optimal 3D printing by reactive extrusion via ViscoTec 2k extruders mounted to a gantry such as the Cosine 3D printer.

[0188] The amount of the hydride silicone component in the addition cured coreactive composition may be from 1 wt. %, 5 wt. %, or 10 wt. % to 15 wt. %, 18 wt. %, or 20 wt. %, or any range using any two of the foregoing values, such as 1 wt. % to 20 wt. %, 5 wt. % to 18 wt. %, or 10 wt. % to 15 wt. %, based on the total weight of the coreactive composition. The amount of vinyl silicone component in the addition cured coreactive composition may be from 80 wt. %, 82 wt. %, or 85 wt. % to 90 wt. %, 95 wt. %, or 99 wt. %, or any range using any two of the foregoing values, such as 80 wt. % to 99 wt. %, 82 wt. % to 95 wt. %, or 85 wt. % to 90 wt. %, based on the total weight of the coreactive composition.

[0189] The gantry also supports a thermal energy source directed towards the nozzle tip. The formulations are printed at print parameters listed in Table 23.Table 23: Print Parameters for Addition-Cured Silicone Formulation at Ambient Conditions and150° C

[0190] The addition cured silicone formulation was printed in single layer stacks ranging from 1 layer to 10 layers at a consistent layer time at ambient conditions and at 150°C using a heat ring. The resolution and buildability of the material printed at 150°C using a heat ring was measured to be better than ambient conditions. Table 24 depicts the relevant open time of the material data with the addition of heat.Table 24: Performance Results

[0191] Wherein particular examples of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the ail to which this disclosure pertains and which fall within the limits of the appended claims.

Claims

CLAIMSWhat is claimed is:

1. An additive manufacturing device, comprising: a first feed line coupled to a first pumping arrangement, the first feed line configured to supply a first coreactive component; a second feed line coupled to a second pumping arrangement, the second feed line configured to supply a second coreactive component; a mixing arrangement fluidly coupled downstream of the first and second pumping arrangements, wherein the first coreactive component and the second coreactive components mix and react within an interior volume of the mixing arrangement to form a coreactive composition; a print nozzle fluidly coupled downstream of the mixing arrangement, wherein upon extrusion from the print nozzle, the coreactive composition cures under ambient conditions; and a thermal energy source configured to supply thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

2. The additive manufacturing device of claim 1, wherein the thermal energy source comprises a conductive thermal energy source mechanically coupled to portion of the additive manufacturing device.

3. The additive manufacturing device of claim 2, wherein the conductive thermal energy source is mechanically coupled to the at least two feed lines, wherein the conductive thermal energy source supplies conductive thermal energy to the first coreactive component and the second coreactive component contained within the feed lines.

4. The additive manufacturing device of claim 2 or claim 3, wherein the conductive thermal energy source comprises heat tape, the heat tape in contact with at least one of the at least two pumping arrangements, the mixing arrangement, and the print nozzle, such that the heat tape supplies conductive thermal energy to the coreactive components.

5. The additive manufacturing device of claim 2, wherein the conductive thermal energy source is at least one of a heated block and a heated nozzle tip coupled to the print nozzle suchthat the at least one of the heated block and the heated nozzle tip transfers thermal energy to the corcactivc composition.

6. The additive manufacturing device of claim 1, wherein the thermal energy source comprises a convective thermal energy source comprising an air source and a heat ring fluidly coupled to the air source, the heat ring including an outer circumference.

7. The additive manufacturing device of claim 6, wherein the heat ring comprises a plurality of air ports, the plurality of air ports being spaced around the outer circumference of the heat ring and angled toward a distal end of the print nozzle; and wherein the air source supplies hot air to the heat ring, such that the hot air is expelled through the plurality of air ports directed at the distal end of the print nozzle to heat the coreactive composition extruded through the print nozzle.

8. The additive manufacturing device of any one of claims 2-4, further comprising a second thermal energy source comprising a convective thermal energy source.

9. The additive manufacturing device of claim 8, wherein the conductive thermal energy source comprises heat tape, the heat tape in contact with at least one of the at least two pumping arrangements, the mixing arrangement, and the print nozzle, such that the heat tape supplies conductive thermal energy to the coreactive components; and wherein the second thermal energy source comprises a convective thermal energy source comprising an air source and a heat ring fluidly coupled to the air source, the heat ring including an outer circumference.

10. The additive manufacturing device of claim 1, wherein the thermal energy source comprises a radiative thermal energy source comprising an Infrared (IR) radiation emitter.

11. The additive manufacturing device of claim 10, wherein the IR radiation emitter comprises a broad emitter that emits a beam of IR light directed at a print surface adjacent to the print nozzle; andwherein the beam of IR light has a beam width from 10 mm to 1000 mm at a point where the beam contacts the print surface.

12. The additive manufacturing device of claim 10, wherein the IR radiation emitter comprises a focused emitter, wherein a beam of IR light is directed down a tube, the tube configured to direct the beam of IR light at a distal end of the print nozzle such that the beam of IR light irradiates a coreactive composition extruded through the distal end of the print nozzle.

13. The additive manufacturing device of any one of claims 1-12, wherein the thermal energy source provides thermal energy intermittently.

14. The additive manufacturing device of any one of claims 1-12, wherein the thermal energy source provides thermal energy continuously.

15. A method of three-dimensional printing using an additive manufacturing device, comprising: combining a first coreactive component and a second coreactive component in a mixing arrangement, the first coreactive component and the second coreactive component reacting to form a coreactive composition; supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition; wherein the thermal energy is at least one of convective thermal energy, conductive thermal energy, or radiative thermal energy; and extruding the coreactive composition from the mixing arrangement through a print nozzle.

16. The method of claim 15, wherein, when the thermal energy is convective thermal energy, the supplying of the convective thermal energy comprises directing heated air via a heat ring towards the coreactive composition as the coreactive composition is extruded through the print nozzle.

17. The method of claim 15, wherein, when the thermal energy is conductive thermal energy, the supplying of the conductive thermal energy comprises at least one of: heat tape mechanically coupled with a portion of the additive manufacturing device; a heat block coupled to a portion of the print nozzle; a heated nozzle coupled to a distal end of the print nozzle.

18. The method of claim 17, wherein when the thermal energy is radiative thermal energy, and wherein the supplying of the radiative thermal energy comprises at least one of: emitting a beam of IR light at a print surface directly adjacent to the additive manufacturing device such that the beam of IR light heats the coreactive composition; and emitting a beam of IR light directed a distal end of a print nozzle of the additive manufacturing device such that the beam of IR light heats at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

19. The method of any one of claims 15-18, wherein supplying thermal energy comprises intermittently supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

20. The method of any one of claims 15-18, wherein supplying thermal energy comprises continuously supplying thermal energy to at least one of the first coreactive component, the second coreactive component, and the coreactive composition.

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