High-speed chemical line-curing composition for 3D composite materials

Abstract

The actinic radiation curable composition comprises (a) at least one monomer of Formula (I), (b) at least one monomer of Formula (II), (c) optionally a urethane (meth)acrylate oligomer, and (d) a photoinitiator, wherein R, R, R, R, R, and R are as defined and each independently represent —(CH) n O(C=O)-CR 10 =CH2 or H. Methods for producing three-dimensional printed composites from the actinic radiation curable compositions are also provided. TIFF2023514435000059.tif47170 TIFF2023514435000060.tif61170

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 62 / 981,512, filed February 25, 2020, entitled "FAST ACTINICALLY CURABLE COMPOSITIONS FOR 3D COMPOSITES," the contents of which are incorporated herein by reference in their entirety for all purposes.

[0002] FIELD OF THE INVENTION The present disclosure relates generally to compositions (matrices), and more particularly to compositions for additive manufacturing systems, wherein the composition is an actinic radiation curable composition. In one embodiment, the actinic radiation curable composition comprises at least one monomer of Formula (I), at least one monomer of Formula (II), an optional urethane (meth)acrylate oligomer, and a photoinitiator. The curable composition may also comprise at least one monomer of Formula (III) and one or more reinforcing agents.

[0003] The present invention also relates to methods for producing three-dimensionally printed composite articles from actinic radiation curable compositions, optionally co-deposited with one or more reinforcing materials, using techniques including stereolithography (SLA), digital light projection (DLP), binder jetting (BJ) or continuous fiber 3D (CF3D®) (Arillaga et al., Additive Manufacturing 2021, 37, 101748). [Background technology]

[0004] Accelerated radical photopolymerization is typically achieved by increasing the photoinitiator concentration. However, such strategies often result in a decrease in molecular weight distribution, an increase in crosslinking events, discoloration, photodecomposition of the cured product, and degradation of material properties due to photoinitiator leaching. Other strategies for increasing the rate of radical photopolymerization have been explored over the past few decades to identify and even design new ethylenically curable monomers and oligomers with inherently fast polymerization rates.

[0005] The radical photopolymerization reactivity of fast-curing ethylenic monomers and oligomers varies depending on their molecular structure and has been explained using various quantitative structure-property relationships (Stansbury, J. Mol. Graph. Model. 2011, 29, 763-772). Although several structure-property relationships have been proposed, results have been mixed on comprehensive models for predicting the photopolymerization rates of commercial (meth)acrylates and (meth)acrylamides. For example, Bowman found that varying the degree of substitution at the α- and β-positions of the ethylene spacer in niche acrylates significantly affected the polymerization reactivity (Bowman, Macromolecules 2005, 3093-3098). Jansen reported an interesting but controversial correlation between the maximum polymerization rate and the Boltzmann mean dipole moment of ethylene-based curable monomers and oligomers and their mixtures (Jansen, Macromolecules, 2002, 35, 7529-7531; Bowman, Polymer 2005, 4735-4742). It has also been reported that the inclusion of heteroatom sulfur in the (meth)acrylate oligomer side chain increases reactivity (Andrzejewski, Polymer Chemistry 2000, 665-673), and more generally, that heteroatom-rich polar side chains lead to improved kinetic activity (Aviyente, Macromolecules 2007, 40(26), 9560-9602).

[0006] Thus, there is a clear need for comprehensive rules to rapidly identify fast-curing monomers and oligomers for specialized applications, where such rapid reactivity can save time and costs, improve properties by reducing photoinitiator concentrations, and even enable novel manufacturing methods. Rapidly radically polymerizing monomers have been shown to exhibit extensive polymerization in the dark compared to traditional ethylene-based curing monomers and oligomers (Bowman, Polymer (Guidf.) 2007, 48(7), 2014-2021). This additive transformation is particularly beneficial in composite applications where opacity or high filler content weakens or scatters light transmission, resulting in undesirable reductions in cure. Therefore, the cure of fast-radical-polymerizing ethylene-based curing monomers is particularly useful for resin formulations designed for non-optical structural composites, such as glass and carbon fiber. The present invention is further beneficial in the additive manufacturing of reinforced structural composites, where cure speeds are required to impart nearly instantaneous green strength and provide structural integrity for three-dimensional articles. Summary of the Invention [Problem to be solved by the invention]

[0007] The use of conventional compositions suitable for additive manufacturing systems that use actinic radiation to cure the composition is challenging to produce and utilize due to the presence of opaque, light-scattering reinforcing materials present in the composite composition, which reduces the extent of cure. Thus, there remains a need for high-speed actinic radiation-curable compositions and more effective methods for producing them. [Means for solving the problem]

[0008] One aspect of the present invention provides a curable composition.

[0009] In one embodiment, the curable composition is an actinically curable composition comprising (or alternatively consisting of): (a) 20 to 80% by mass of at least one (meth)acrylamide (i.e., acrylamide or methacrylamide) that satisfies the following criteria: (1) an average dipole moment of 2.5 or greater; (2) a hydrogen atom, a methyl group, or a methylene group is present at the α-position relative to the nitrogen atom of the acrylamide or methacrylamide, and a hydrogen atom, a methyl group, a methylene group, a methine group, a heteroatom, or an aromatic group is present at the β-position relative to the nitrogen atom; and (3) at least two heteroatoms per molecule of acrylamide or methacrylamide; (b) 10 to 60% by weight of at least one monomer of formula (II): [ka] (c) 0 to 30% by weight of one or more urethane (meth)acrylate oligomers; and (d) 0.1 to 5% by weight of one or more photoinitiators; where R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where at least two of R7, R8, and R9 are -(CH2) n O(C=O)-CR 10 =CH2, R 10 is selected from the group consisting of H and C1-C3 alkyl; n is 1, 2, 3 or 4.

[0010] In one embodiment, the curable composition includes an actinic radiation curable composition comprising (or alternatively consisting of): [ka] (b) 10 to 60% by weight of at least one monomer of formula (II): [ka] (c) 0 to 30% by weight of one or more urethane (meth)acrylate oligomers; and (d) 0.1 to 5% by weight of one or more photoinitiators; where: R1 is H or C1-C3 alkyl; R2 and R3 are H, C1-C3 alkyl, CH2-CH(OH)C1-C3 alkyl and (CH2) m X, each independently selected from the group consisting of or R2 and R3 together with the nitrogen atom to which they are attached form a 3- to 6-membered saturated heterocyclic ring; X is OR4, SR4, NR5R6, OP(=O)(OR4)2, CH2P(=O)(OR4)2, or an aromatic group; each R4 is independently selected from the group consisting of H and C1-C4 alkyl; R5 and R6 are each independently selected from the group consisting of H and C1-C3 alkyl; m is 1, 2, 3, 4 or 5; R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where at least two of R7, R8 and R9 are -(CH2) n O(C=O)-CR 10 =CH2; R 10 is selected from the group consisting of H and C1-C3 alkyl; n is 1, 2, 3 or 4.

[0011] In one embodiment of the curable composition, R1 is H, and R2 and R3 together with the nitrogen atom to which they are attached form a 5- or 6-membered saturated heterocyclic ring of the monomer of formula (I).

[0012] In a further embodiment of the curable composition, for the monomer of formula (II), at least one of R7, R8 and R9 is (CH2) where n is 2. n O(C=O)-CR 10 =CH2.

[0013] In a further embodiment of the curable composition, for the monomer of formula (II), at least two of R7, R8 and R9 are (CH2) where n is 2. n O(C=O)-CR 10 =CH2.

[0014] In a further embodiment of the curable composition, for the monomer of formula (II), at least one of R7, R8 and R9 is selected such that n is 2 and R 10 is H(CH2) n O(C=O)-CR 10 =CH2.

[0015] In a further embodiment of the curable composition, for the monomer of formula (II), at least two of R7, R8 and R9 are selected such that n is 2 and R 10 is H(CH2) n O(C=O)-CR 10 =CH2.

[0016] In one embodiment, the acrylamide / methacrylamide or monomer of formula (I) is selected from the group consisting of: [ka]

[0017] In one embodiment, the monomer of formula (I) is acryloylmorpholine (ACMO): [ka]

[0018] In one embodiment, the monomer of formula (II) is tris(2-hydroxyethyl) isocyanurate triacrylate (M370) (also referred to in the present disclosure as SR368): [ka]

[0019] In one embodiment of the curable composition, the monomer of formula (I) is ACMO: [ka] and the monomer of formula (II) is M370: [ka]

[0020] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370 and a photoinitiator.

[0021] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a urethane (meth)acrylate oligomer, and a photoinitiator.

[0022] In one embodiment, the curable composition further comprises a reinforcing material (filler).

[0023] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a reinforcing agent, and a photoinitiator.

[0024] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a urethane (meth)acrylate oligomer, a reinforcing agent, and a photoinitiator.

[0025] In a further embodiment, the reinforcing material is an opaque reinforcing material (opaque filler) or a light-scattering reinforcing material (light-scattering filler).

[0026] In one embodiment, the reinforcing material is selected from the group consisting of glass fiber, fiberglass, chopped carbon fiber, continuous carbon fiber, Kevlar® fiber, ceramic fiber, asbestos, polybenzimidazole fiber, polysulfonamide fiber, poly(phenylene oxide fiber), vegetable fiber, wood fiber, mineral fiber, plastic fiber, metal wire, and aramid fiber, and optionally, one or more of nylon, polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), and polycarbonate may be present.

[0027] In one embodiment, the reinforcing material is not fiberglass.

[0028] In one embodiment, the reinforcement material is fiberglass or continuous carbon fiber.

[0029] In one embodiment, the urethane (meth)acrylate oligomer is a polyurethane (meth)acrylate oligomer (SARTOMER® CN989 (PHOTOMER® 6008), SARTOMER® CN9005 (PHOTOMER® 6010), SARTOMER® CN964 (PHOTOMER® 6019), SARTOMER® CN989 (PHOTOMER® 6184), PHOTOMER® 6630, SARTOMER® CN929 (PHOTOMER® 6892), SARTOMER® CN963, SARTOMER® CN945, SARTOMER® CN944, SARTOMER® CN989, SARTOMER® CN959, and SARTOMER® CN964 (PHOTOMER® 6019). CN981).

[0030] In one embodiment, the photoinitiator is selected from the group consisting of benzophenones, benzoin ethers, benzil ketals, α-hydroxyalkylphenones, α-alkoxyalkylphenones, α-aminoalkylphenones, and acylphosphines (oxides).

[0031] In one embodiment, the photoinitiator is 1-hydroxy-cyclohexyl-phenyl-ketone (IRGACURE® IC-184); 2,4,6-trimethylbenzoyldiphenylphosphine oxide (LUCIRIN® TPO); 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (LUCIRIN® TPO-L); bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide (IRGACURE® 819); 2-methyl-1-(4-methylthio)phenyl-2-(4-morpholinyl)-1-propanone (IRGACURE® 907) and 1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one (IRGACURE® 2959); 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (IRGACURE® 1007); 369); 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)-benzyl)-phenyl)-2-methylpropan-1-one (IRGACURE® 127) and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (IRGACURE® 379).

[0032] In one embodiment, the curable composition further comprises a (meth)acrylate (i.e., an acrylate or methacrylate) that meets the following criteria: (1) an average dipole moment of 2.5 or greater; (2) a methyl or methylene group alpha to the oxygen atom of the acrylate or methacrylate, and a hydrogen, methyl, methylene, methine, heteroatom, or aromatic group beta to the oxygen atom; and (3) three or more heteroatoms per acrylate molecule and four or more heteroatoms per methacrylate molecule.

[0033] In one embodiment, the curable composition further comprises 1 to 30 wt. % of a (meth)acrylate (i.e., acrylate or methacrylate) monomer of formula (III): [ka] where: Each R 11 are independently H or C1-C3 alkyl; R 12 is selected from the group consisting of: R 11 is H, a 3- to 7-membered heterocycle containing at least one of N, O, or S, and R 11 is C1-C3 alkyl, a 4-7 membered heterocycle containing at least two of N, O or S; Optionally branched C2-C 10 an alkane chain, R 11 is H, at least one carbon atom of the alkane chain is substituted with N, O, S or P, the alkane chain terminates with a C1-C3 alkyl group, and the optional branching group is a C1-C3 alkyl group; 10 alkane chains; Optionally branched C3-C 10 an alkane chain, R 11is C1-C3 alkyl, at least two carbon atoms of the alkane chain are substituted with N, O, S or P, the alkane chain terminates with a C1-C3 alkyl group, and the optional branching group is a C1-C3 alkyl group; 10 alkane chains; and Optionally branched C2-C 20 an alkane chain, one or more carbon atoms of which may be optionally substituted with N, O, S, or P, the alkane chain terminating in an acrylate group (-OC(=O)-CH=CH2) or a methacrylate group (-OC(=O)-C(CH3)=CH2), and the optional branching group is a C1-C3 alkyl group; 20 in alkane chains.

[0034] In embodiments of the acrylate monomer of formula (III), R 11 is H and R 12 is selected from the group consisting of: [ka] wherein Cy is a cycloalkyl group having 3 to 7 ring carbons (cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl).

[0035] In one embodiment of the monomer of formula (III), R 11 is a C1-C3 alkyl group, and R 12 is selected from the group consisting of: [ka] wherein Cy is a cycloalkyl group having 3 to 7 ring carbons (cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl).

[0036] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a (meth)acrylate monomer of formula (III), and a photoinitiator.

[0037] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a (meth)acrylate monomer of formula (III), a urethane (meth)acrylate oligomer, and a photoinitiator.

[0038] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a (meth)acrylate monomer of formula (III), a reinforcing agent, and a photoinitiator.

[0039] In one embodiment, the curable composition comprises (or alternatively consists of) ACMO, M370, a (meth)acrylate monomer of formula (III), a urethane (meth)acrylate oligomer, a reinforcing agent, and a photoinitiator.

[0040] In one embodiment, the curable composition comprises (or alternatively consists of): 20 to 80% by weight of ACMO as monomer (I); 10-60% by mass of M370 as monomer (II); 0 to 30% by weight of PHOTOMER® 6019 as a coating agent; and 0.1 to 5 wt% IRGACURE® 819 as a photoinitiator.

[0041] In one embodiment, the curable composition comprises: 20-50% by weight of ACMO as monomer (I); 30-60% by mass of M370 as monomer (II); 5 to 20% by weight of PHOTOMER® 6019 as a coating agent; and 1-5 wt% IRGACURE® 819 as a photoinitiator.

[0042] In one embodiment, the curable composition comprises (or alternatively consists of): 20 to 80% by weight of ACMO as monomer (I); 10-60% by mass of M370 as monomer (II); 0-30% by weight of PHOTOMER® 6019 as a coating agent; 0.1 to 5% by weight of IRGACURE® 819 as a photoinitiator; and Reinforcement material.

[0043] In one embodiment, the curable composition comprises: 20-50% by weight of ACMO as monomer (I); 30-60% by mass of M370 as monomer (II); 5 to 20% by weight of PHOTOMER® 6019 as a coating agent; 1 to 5% by weight of IRGACURE® 819 as a photoinitiator; and Reinforcement material.

[0044] In one embodiment, the curable composition comprises: 28.8% by weight of ACMO as monomer (I); 52.9% by mass of M370 as monomer (II); 14.4% by weight of PHOTOMER® 6019 as a coating agent; and 3.8 wt% IRGACURE® 819 as photoinitiator.

[0045] In one embodiment, the curable compositions described herein are three-dimensional (3D) printable.

[0046] A further aspect is a construct comprising: opaque or light-scattering reinforcing material; and A curable composition (matrix) as described in this disclosure at least partially coating an opaque or light-scattering reinforcing material.

[0047] In one embodiment, the structure comprises: opaque or light-scattering reinforcing material; and 1. A curable composition (matrix) at least partially coating an opaque or light-scattering reinforcing material, the curable composition (matrix) comprising: 20-80 mass% ACMO; 10-60 mass% M370; 0 to 30% by weight of PHOTOMER® 6019; and 0.1 to 5% by weight of IRGACURE® 819.

[0048] In one embodiment, the composition comprises: 28.8% by mass ACMO; 52.9 mass% M370; 14.4% by weight of PHOTOMER® 6019; and 3.8% by weight of IRGACURE® 819.

[0049] A further aspect is a method of curing a curable composition described herein, comprising exposing the curable composition to actinic radiation sufficient to cure the curable composition. In one embodiment, the curable composition further comprises a reinforcing material.

[0050] A further aspect is a structure produced by an additive manufacturing system, the structure comprising a reinforcement material and a composition (matrix) at least partially coating the reinforcement material, the composition comprising ACMO; M370; PHOTOMER® 6019; and IRGACURE® 819.

[0051] One embodiment is a structure manufactured by an additive manufacturing system, the structure including an opaque reinforcement material and a composition (matrix) at least partially coating the opaque reinforcement material, the composition (matrix) including 20-80% by weight ACMO; 10-60% by weight M370; 0-30% by weight Photomer® 6019; and 0.1-5% by weight IRGACURE® 819.

[0052] A further aspect is a method of making a three dimensional printed composite article, comprising: ejecting an actinic radiation curable composition as described herein from a print head, the actinic radiation curable composition including a reinforcing material; moving the print head during ejection of the actinic radiation curable composition; and Irradiating the actinic radiation curable composition with light to form a cured three-dimensional printed composite article.

[0053] A further aspect is a method of making a three-dimensionally printed carbon bonded composite article using Continuous Fiber 3D (CF3D®), comprising: Irradiating an actinic radiation curable composition as described in this disclosure in the presence of continuous carbon fibers to form a cured three dimensional printed carbon bonded composite article.

[0054] In one embodiment, the curable composition is applied as a single deposition. In one embodiment, the cured composite article has low optical clarity or scatters light.

[0055] A further aspect is a printhead comprising a curable composition as described in this disclosure.

[0056] The figures reflect particular embodiments of the invention and are not intended to limit the scope of the invention as described in this disclosure. [Brief explanation of the drawings]

[0057] [Figure 1] FIG. 1 is a schematic diagram of an exemplary additive manufacturing system. [Figure 2] FIG. 2 shows the results of an analysis of a composition (matrix) suitable for use in the additive manufacturing system of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0058] Accelerated radical photopolymerization is typically achieved by increasing the photoinitiator concentration. However, other methods for accelerating radical photopolymerization include increasing the photoinitiator concentration, increasing the irradiation intensity, or using an inert blanket such as nitrogen or argon. All of these methods have limited returns in terms of accelerating polymerization. For continuous composite materials, one objective of the present invention is to use high irradiation intensity. To achieve this objective, novel "fast" monomers were needed. The present invention is directed to actinic radiation-curable resin compositions for the additive manufacturing of 3D printing materials, which comprise fast-curing monomers (also referred to in this disclosure as fast monomers). To facilitate the identification of acrylamide and acrylate monomers that can be qualified as fast-curing monomers suitable for inclusion in the actinic radiation-curable compositions described in this disclosure, the inventors developed a set of three requirements based on "functional group substitution," "Boltzmann average dipole moment," and "number of heteroatoms per molecule." These three requirements are collectively referred to as the "three-requirement test" and include the "substitution requirement," the "average dipole moment requirement," and the "heteroatoms per molecule" requirement.

[0059] Replacement requirements The "substitution" requirement of the three requirement test is that in the case of (meth)acrylate, the α-position relative to the oxygen atom of the ester functional group is a methyl group (-CH3) or a methylene group (-CH2-), and the β-position is hydrogen, a methyl group (-CH3), a methylene group (-CH2-), [ka] This is based on the observation that a heteroatom or an aromatic group is preferred. In this disclosure, the term "(meth)acrylate" refers to both acrylate (-OC(=O)-CH=CH2) and methacrylate (-OC(=O)-C(CH3)=CH2) compounds. In the case of (meth)acrylamide, the α-position is unsubstituted, a methyl group (-CH3), or a methylene group (-CH2-), and the β-position is hydrogen, a methyl group (-CH3), a methylene group (-CH2-), or [ka] Preferably, it is a heteroatom or an aromatic group. In this disclosure, the term "(meth)acrylamide" refers to both acrylamide (-NR-C(=O)-CH=CH2) and methacrylamide (-NR-C(=O)-C(CH3)=CH2) compounds. The preferences for these are as follows: [ka] R1 = H or CH3 R2=N or O Rule: In (meth)acrylates, the alpha and beta positions to the ester oxygen include: - Alpha = methyl or methylene. - Beta = methyl, methylene, methine, heteroatom, or aromatic. [ka] Rule: In (meth)acrylamides, the alpha and beta positions relative to the amide nitrogen include: Alpha = hydrogen, methyl or methylene. Beta = hydrogen, methyl or methylene, methine, heteroatom, or aromatic. [ka]

[0060] When defining substitution requirements, a "heteroatom" is N, O, S, or P. When defining substitution requirements, "aromatic" refers to any aromatic carbocyclic moiety, such as, but not limited to, phenyl or naphthyl, and any 5-10 membered aromatic heterocyclic ring containing at least one carbon atom and having at least one heteroatom selected from nitrogen, oxygen, and sulfur, including, but not limited to, both monocyclic and bicyclic rings. Representative aromatic heterocyclic compounds include, but are not limited to, furyl, benzofuranyl, thiophenyl, benzothiophenyl, pyrrolyl, indolyl, isoindolyl, azaindolyl, pyridyl, quinolinyl, isoquinolinyl, oxazolyl, isoxazolyl, benzoxazolyl, pyrazolyl, imidazolyl, benzimidazolyl, thiazolyl, benzothiazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, cinnolinyl, phthalazinyl, and quinazolinyl.

[0061] In the case of a multifunctional asymmetric molecule in which one (meth)acrylate functional group has the required substituents and the other does not, the entire molecule qualifies if one of the functional groups qualifies, but it is possible for the molecule to fail all three aspects of the test.

[0062] A general comparison of the photoreactivity trends of acrylates and acrylamides is as follows: [ka]

[0063] Boltzmann average dipole moment requirement Of the three requirements, the "Boltzmann average dipole moment" requirement is based on the observation that for (meth)acrylates and (meth)acrylamides, the Boltzmann average dipole moment is preferably 2.5 or more, for example 2.6 or more, for example 2.7 or more, for example 2.8 or more, for example 2.9 or more, for example 3.0 or more, for example 3.1 or more, for example 3.2 or more, for example 3.3 or more. Exemplary ranges include 2.5 to 7.5, for example, 2.5 to 7.0, for example, 2.5 to 6.5, for example, 2.5 to 6.0, for example, 2.5 to 5.5, for example, 2.5 to 5.0, 2.7 to 7.5, for example, 2.7 to 7.0, for example, 2.7 to 6.5, for example, 2.7 to 6.0, for example, 2.7 to 5.5, for example, 2.7 to 5.0, for example, 2.9 to 7.5, for example, 2.9 to 7.0, for example, 2.9 to 6.5, for example, 2.9 to 6.0, for example, 2.9 to 5.5, for example, 2.9 to 5.0.

[0064] Calculation of the Boltzmann average dipole moment is well known (C. Rowley, J. Chem. Phys. A 2014, 118, 3678-3687; U.S. Patent Application Publication No. 20160068467 A1) and is determined in this disclosure by employing the following conventional methods: Wavefunction Spartan 18 Parallel Suite, Equilibrium Conformer, density functional, B97M-V, 6-311+G(2df,2p)(6-311G*), B3LYP, and Global Calculations. Wavefunction Spartan 18 Parallel Suite is molecular modeling software used to determine molecular structures and calculate chemical properties, and is widely used in industry and academia. Equilibrium Conformer identifies the lowest-energy conformer of a molecule. Density functional theory is a quantum mechanical modeling method used to calculate the energy and wave functions of atoms and molecules containing large numbers of electrons. B97M-V is a specific density functional model. 6-311+G(2df,2p) (6-311G*) is a basis set, or a set of functions representing electronic wave functions, for converting the model's partial differential equations into algebraic equations for efficient computer execution. B3LYP is a density functional model used to calculate energies, wave functions, equilibrium and transition state geometries, and vibrational frequencies using a specified basis set. In global calculations, all atoms and molecules are calculated as specified. These methods combine to provide the Boltzmann-weighted dipole moment of the equilibrium composition of the atom or molecule under investigation. It is noteworthy that those skilled in the art can obtain similar values ​​by employing alternative models widely accepted in academia and industry, such as HF (Hartree-Fock), MP2 (Möller-Plesset), B3LYP hybrid functional theory, or linear-response coupled cluster-singles and doubles calculations (LR-CCSD) and software.The above-described combination method employed in the present invention is preferred because it is considered rigorous by current standards and provides high accuracy.

[0065] Heteroatom Requirement per Molecule Of the three requirements, the "number of heteroatoms per molecule" requirement is based on the observation that in the case of acrylates, it is preferable that three or more heteroatoms are present in one molecule. In the case of (meth)acrylates, it is preferable that four or more heteroatoms are present in one molecule. In the case of (meth)acrylamides, it is preferable that two or more heteroatoms are present in one molecule. When defining the requirement for the number of heteroatoms per molecule, a "heteroatom" is N, O, S, or P.

[0066] In one embodiment, (meth)acrylate and (meth)acrylamide monomers must meet all three requirements to be considered suitable for inclusion in the curable compositions of the present invention. In another embodiment, monomers that meet two of the three requirements can also be considered suitable for inclusion in the curable compositions of the present invention. In one embodiment, monomers that meet at least the average dipole moment requirement and the substitution requirement are suitable for inclusion in the curable compositions. In another embodiment, monomers that meet at least the average dipole moment requirement and the heteroatom requirement are suitable for inclusion in the curable compositions. Heteroatoms present in multifunctional (meth)acrylates are not treated differently compared to monofunctional components, and therefore the total number of heteroatoms in multifunctional (meth)acrylates is tallied in the usual manner.

[0067] curable composition In one embodiment, the curable composition comprises: (a) 20 to 80% by weight of at least one (meth)acrylamide (i.e., acrylamide or methacrylamide) that meets the following criteria: (1) an average dipole moment of 2.5 or greater, or 2.7 or greater, or 2.9 or greater, or in the range of 2.5 to 7.5, including the ranges described herein for this requirement; (2) a hydrogen, methyl, or methylene group at the alpha position relative to the nitrogen atom of the acrylamide or methacrylamide, and a hydrogen, methyl, methylene, methine, heteroatom (N, O, S, or P), or aromatic group at the beta position relative to the nitrogen atom; and (3) two or more heteroatoms per molecule of acrylamide or methacrylamide; (b) 10 to 60% by weight of at least one monomer of formula (II): [ka] (c) 0 to 30% by mass of a urethane (meth)acrylate oligomer; and (d) 0.1 to 5 mass% of a photoinitiator; where: R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where at least two of R7, R8 and R9 are -(CH2) n O(C=O)-CR 10 =CH2; R 10 is selected from the group consisting of H and C1-C3 alkyl; n is 1, 2, 3 or 4.

[0068] In one embodiment, the curable composition (without the reinforcing material) has a Tg of at least 80°C, such as at least 100°C, at least 150°C, such as at least 200°C, for example from at least 80°C to 230°C, such as from at least 100°C to 230°C, for example from at least 150°C to 230°C.

[0069] In another embodiment, the curable composition comprises: (a) 20 to 80% by weight of at least one monomer of formula (I): [ka] (b) 10 to 60% by weight of at least one monomer of formula (II): [ka] (c) 0 to 30% by mass of a urethane (meth)acrylate oligomer; and (d) 0.1 to 5% by weight of a photoinitiator.

[0070] Regarding the monomer of formula (I) as component (a): R1 is H or C1-C3 alkyl, where C1-C3 alkyl includes methyl, ethyl, propyl, and isopropyl; R2 and R3 are H, C1-C3 alkyl (wherein C1-C3 alkyl includes methyl, ethyl, propyl, and isopropyl), CH2-CH(OH)C1-C3 alkyl (wherein C1-C3 alkyl includes methyl, ethyl, propyl, and isopropyl), and (CH2) m X, each independently selected from the group consisting of or R2 and R3 together with the nitrogen atom to which they are attached form a 3- to 6-membered saturated heterocyclic ring (wherein the 3- to 6-membered saturated heterocyclic ring is selected from the group consisting of aziridine, azetidine, pyrrolidine, imidazolidine, pyrazolidine, thiazolidine, isothiazolidine, piperidine, piperazine, morpholine, and thiomorpholine); X is OR4, SR4, NR5R6, OP(=O)(OR4)2, CH2P(=O)(OR4)2, or an aromatic group; R4 is selected from the group consisting of H and C1-C4 alkyl (wherein C1-C4 alkyl includes methyl, ethyl, propyl, butyl, isopropyl, and isobutyl); R5 and R6 are each independently selected from the group consisting of H and C1-C3 alkyl (wherein C1-C3 alkyl is methyl, ethyl, propyl, and isopropyl), or R5 is H and R6 is -NH-C(=O)-CH=CH2 or -NH-C(=O)-C(CH3)=CH2; m is 1, 2, 3, 4 or 5.

[0071] Another embodiment of the monomer of formula (I) as component (a) is R1 is H or methyl; R2 is H and R3 is H, methyl, CH2-CH(OH)C1-C3 (where C1-C3 alkyl is methyl or ethyl), and (CH2) m X; or or R2 and R3, together with the nitrogen atom to which they are attached, form a 5- to 6-membered saturated heterocyclic ring, wherein the 5- to 6-membered saturated heterocyclic ring is selected from the group consisting of piperidine, piperazine, morpholine, and thiomorpholine; X is OR4, SR4, NR5R6 or an aromatic group; R4 is selected from the group consisting of H and C1-C4 alkyl (wherein C1-C4 alkyl includes methyl, ethyl, propyl, butyl, isopropyl, and isobutyl); R5 and R6 are each independently selected from the group consisting of H and C1-C3 alkyl (wherein C1-C3 alkyl includes methyl, ethyl, propyl, and isopropyl), or R5 is H and R6 is -NH-C(=O)-CH=CH2 or -NH-C(=O)-C(CH3)=CH2; m is 1, 2, 3, 4 or 5.

[0072] The monomer of formula (I) may be present in an amount of 20 to 80% by weight, such as 20 to 70% by weight, for example 20 to 60% by weight, for example 20 to 50% by weight, such as 20 to 40% by weight, for example 25 to 60% by weight, for example 25 to 50% by weight, for example 25 to 45% by weight, for example 30 to 60% by weight, based on the total composition.

[0073] When the monomer of formula (I) is ACMO, ACMO is present in an amount of 25% by weight or more, such as 35% by weight or more, such as 45% by weight or more, for example 50% by weight or more, with an upper limit of 80% by weight.

[0074] Regarding the monomer of formula (II) as component (b): R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where at least two of R7, R8 and R9 are -(CH2) n O(C=O)-CR 10 =CH2.

[0075] R 10 is selected from the group consisting of H and C1-C3 alkyl (wherein C1-C3 alkyl includes methyl, ethyl, propyl, and isopropyl); n is 1, 2, 3 or 4.

[0076] In various embodiments, One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 1; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 1; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 1; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 2; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 3; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 3; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 3; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 4; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 4; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 4; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, n is 1, and R 10 is H; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 1, and R 10 is H; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, n is 1, and R 10 is H; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10=CH2, where n is 2, and R 10 is H; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 is H; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, n is 2, and R 10 is H; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 3, and R 10 is H;

[0077] Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 3, and R 10 is H; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, n is 3, and R 10 is H; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 4, and R 10 is H; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 4, and R 10 is H; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, n is 4, and R 10 is H; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10=CH2, where n is 1, and R 10 is CH3; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 1, and R 10 is CH3; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 1, and R 10 is CH3; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 is CH3; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 is CH3; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 is CH3; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 3, and R 10 is CH3; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 3, and R 10 is CH3; All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 3, and R 10 is CH3; One of R7, R8 and R9 is (CH2) n O(C=O)-CR 10=CH2, where n is 4, and R 10 is CH3; Two of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 4, and R 10 is CH3; or All three of R7, R8 and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 4, and R 10 is CH3.

[0078] The monomer of formula (II) may be present in an amount of 10 to 60% by weight, such as 20 to 60% by weight, for example 20 to 50% by weight, for example 20 to 40% by weight, such as 25 to 60% by weight, for example 25 to 50% by weight, for example 25 to 45% by weight, for example 30 to 60% by weight, based on the total composition.

[0079] Regarding the optional urethane (meth)acrylate oligomer as component (C): Urethane (meth)acrylates (sometimes referred to as "polyurethane (meth)acrylates") that can be used in the curable compositions of the present invention include urethanes based on aliphatic and / or aromatic polyester polyols, polyether polyols, and polycarbonate polyols, and aliphatic and / or aromatic polyester diisocyanates and polyether diisocyanates capped with (meth)acrylate end groups.

[0080] In various embodiments, urethane (meth)acrylates can be prepared by reacting an aliphatic and / or aromatic polyisocyanate (e.g., diisocyanate, triisocyanate) with an OH-terminated polyester polyol (including aromatic polyester polyol, aliphatic polyester polyol, and aliphatic / aromatic polyester polyol mixtures), polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethylsiloxane polyol, or polybutadiene polyol, or a combination thereof, to form an isocyanate-functionalized oligomer, which can then be reacted with a hydroxyl-functionalized (meth)acrylate, such as hydroxyethyl (meth)acrylate or hydroxypropyl (meth)acrylate, to provide terminal (meth)acrylate groups. For example, the urethane (meth)acrylate can contain two, three, four, or more (meth)acrylate functional groups per molecule. As known in the art, other addition sequences can also be performed to prepare polyurethane (meth)acrylates. For example, a hydroxyl-functionalized (meth)acrylate may be first reacted with a polyisocyanate to give an isocyanate-functionalized (meth)acrylate, which may then be reacted with an OH-terminated polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethylsiloxane polyol, polybutadiene polyol, or a combination thereof. In yet another embodiment, a polyisocyanate may first be reacted with a polyol, including any of the above types of polyols, to give an isocyanate-functionalized polyol, which may then be reacted with a hydroxyl-functionalized (meth)acrylate to give a polyurethane (meth)acrylate. Alternatively, all components may be combined and reacted simultaneously.

[0081] Any of the above types of oligomers may be modified with amines or sulfides (e.g., thiols) according to procedures known in the art. Such amine- and sulfide-modified oligomers can be prepared, for example, by reacting a relatively small amount (e.g., 2-15%) of the (meth)acrylate functional groups present in the base oligomer with an amine (e.g., a secondary amine) or sulfide (e.g., a thiol), where the modifying compound adds to the carbon-carbon double bond of the (meth)acrylate in a Michael addition reaction.

[0082] Examples of suitable urethane oligomers include those commercially available from Henkel Corp. under the trade name PHOTOMER® (e.g., PHOTOMER® 6008, PHOTOMER® 6010, PHOTOMER® 6019, PHOTOMER® 6184, PHOTOMER® 6630, and PHOTOMER® 6892), those commercially available from UCB Radcure Inc. under the trade name EBECRYL® (e.g., EBECRYL® 220, 284, 4827, 4830, 6602, 8400, and 8402), those commercially available under the trade name RXO® (e.g., RXO® 1336), and those commercially available under the trade name RSX® (e.g., RSX® 3604, 89359, 92576). Other useful acrylated urethanes are commercially available from Sartomer Co. under the trade name SARTOMER® (e.g., SARTOMER® 9635, 9645, 9655, 963-B80, and 966-A80) and from Morton International under the trade name UVITHANE® (e.g., UVITHANE® 782). Alternatively, conventional urethane acrylate oligomers may be formed by reacting a polyol, such as a diol, with a multifunctional isocyanate, such as a diisocyanate, and then end-capping with a hydroxy-functional (meth)acrylate. To impart hardness to the cured film, the urethane oligomer preferably contains three or more (meth)acrylate groups; for example, the urethane oligomer has six or more (meth)acrylate groups. The urethane oligomers may be used alone or in a mixture of two or more.

[0083] The urethane oligomer may be present in an amount of 0 to 30% by weight, such as 1 to 25% by weight, for example 5 to 25% by weight, for example 5 to 20% by weight, for example 10 to 25% by weight, for example 10 to 20% by weight, based on the total composition.

[0084] Regarding the photoinitiator as component (d): In certain embodiments of the present invention, the actinic radiation-curable compositions described herein comprise at least one photoinitiator and are curable by radiation energy (visible light, ultraviolet light). A photoinitiator can be considered any type of substance that, upon exposure to radiation (e.g., actinic radiation), forms a chemical species that initiates the desired reaction to cure the polymerizable organic material present in the curable composition. Suitable photoinitiators include free-radical photoinitiators.

[0085] Free radical polymerization initiators are substances that form free radicals when irradiated with light. The use of free radical photoinitiators is particularly preferred.

[0086] Non-limiting examples include phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide as a photoinitiator. Non-limiting examples of suitable acylphosphine oxides include, but are not limited to, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-(2,4-bispentyloxyphenyl)phosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, and combinations thereof.

[0087] Non-limiting types of free radical photoinitiators suitable for use in the curable compositions of the present invention include, for example, benzoins, benzoin ethers, acetophenones, benzil, benzil ketals, anthraquinones, phosphine oxides, α-hydroxyketones, phenylglyoxylates, α-aminoketones, benzophenones, thioxanthones, xanthones, acridine derivatives, phenazene derivatives, quinoxaline derivatives, and triazine compounds. Particularly suitable free radical photoinitiators include 2-methylanthraquinone, 2-ethylanthraquinone, 2-chloroanthraquinone, 2-benzylanthraquinone, 2-t-butylanthraquinone, 1,2-benzo-9,10-anthraquinone, benzil, benzoins, benzoin ethers, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, α-methylbenzoin, α-phenylbenzoin, Michler's ketone (Michler's ketone), and the like. ketone), acetophenones such as 2,2-dialkoxybenzophenones, 1-hydroxyphenyl ketone, benzophenone, 4,4'-bis-(diethylamino)benzophenone, acetophenone, 2,2-diethyloxyacetophenone, diethyloxyacetophenone, 2-isopropylthioxanthone, thioxanthone, diethylthioxanthone, 1,5-acetonaphthylene, ethyl-p-dimethylaminobenzoate, benzyl ketone, α-hydroxy ketone, 2,4,6-trimethylbenzoyl Diphenylphosphine oxide, benzil dimethyl ketal, 2,2-dimethoxy-1,2-diphenylethanone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone-1, 2-hydroxy-2-methyl-1-phenyl-propanone, oligomeric α-hydroxy ketones, benzoylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl-4-dimethylaminobenzoate, ethyl(2,4,6-Trimethylbenzoyl)phenylphosphinate, Anisoin, Anthraquinone, Anthraquinone-2-sulfonic acid sodium salt monohydrate, (Benzene)tricarbonylchromium, Benzil, Benzoin isobutyl ether, Benzophenone / 1-hydroxycyclohexyl phenyl ketone 50 / 50 blend, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 4-benzoylbiphenyl, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, 4,4'- Bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, camphorquinone, 2-chlorothioxanthen-9-one, dibenzosuberenone, 4,4'-dihydroxybenzophenone, 2,2-dimethoxy-2-phenylacetophenone, 4-(dimethylamino)benzophenone, 4,4'-dimethylbenzyl, 2,5-dimethylbenzophenone, 3,4-dimethylbenzophenone, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide / 2-hydrogen 50 / 50 blend of 2-methylpropiophenone, 4'-ethoxyacetophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, ferrocene, 3'-hydroxyacetophenone, 4'-hydroxyacetophenone, 3-hydroxybenzophenone, 4-hydroxybenzophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methylpropiophenone, 2-methyl Examples of suitable anthracene derivatives include, but are not limited to, benzophenone, 3-methylbenzophenone, methylbenzoyl formate, 2-methyl-4'-(methylthio)-2-morpholinopropiophenone, phenanthrenequinone, 4'-phenoxyacetophenone, (cumene)cyclopentadienyl iron(II) hexafluorophosphate, 9,10-diethoxy and 9,10-dibutoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, thioxanthen-9-one, and combinations thereof.

[0088] In one embodiment, the photoinitiator is 1-hydroxy-cyclohexyl-phenyl-ketone (IRGACURE® IC-184); 2,4,6-trimethylbenzoyldiphenylphosphine oxide (LUCIRIN® TPO); 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (LUCIRIN® TPO-L); bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide (IRGACURE® 819); 2-methyl-1-(4-methylthio)phenyl-2-(4-morpholinyl)-1-propanone (IRGACURE® 907) and 1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one (IRGACURE® 2959); 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (IRGACURE® 1007); 369); 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)-benzyl)-phenyl)-2-methylpropan-1-one (IRGACURE® 127); and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (IRGACURE® 379).

[0089] The photoinitiator may be present in an amount of 0.1 to 5% by weight, such as 0.5 to 5% by weight, such as 1 to 5% by weight, such as 2 to 5% by weight, based on the total composition.

[0090] Optional monomer of formula (III) In one embodiment of the present invention, the curable resin comprises, in addition to components (a), (b), (d), and optionally (c) described herein, at least one (meth)acrylate (i.e., acrylate or methacrylate) monomer, wherein the acrylate or methacrylate monomer meets the following criteria: (1) having an average dipole moment of 2.5 or greater, or 2.7 or greater, or 2.9 or greater, or in the range of 2.5 to 7, inclusive, including the ranges set forth in this disclosure for this requirement; (2) a methyl or methylene group is present in the alpha position relative to the oxygen atom of the acrylate or methacrylate, and a hydrogen, methyl, methylene, methine, heteroatom (N, O, S, or P), or aromatic group is present in the beta position relative to the oxygen atom; and (3) In the case of acrylates, there are three or more heteroatoms per molecule, and in the case of methacrylates, there are four or more heteroatoms per molecule.

[0091] In another embodiment of the present invention, the curable resin comprises, in addition to components (a), (b), (d) and optionally (c) described herein, at least one monomer of formula (III): [ka] where: Each R 11 are independently H or C1-C3 alkyl (wherein C1-C3 alkyl is methyl, ethyl, propyl, or isopropyl); R 12 is selected from the group consisting of: R 11 is H, a 3- to 7-membered heterocycle containing at least one of N, O, or S, and R 11 is C1-C3 alkyl, a 4-7 membered heterocycle containing at least two of N, O or S; Optionally branched C2-C 10 an alkane chain, R 11 is H, at least one carbon atom of the alkane chain is substituted with N, O, S or P, the alkane chain terminates with a C1-C3 alkyl group, and the optional branching group is a C1-C3 alkyl group; 10 alkane chains; Optionally branched C3-C 10 an alkane chain, R 11is C1-C3 alkyl, at least two carbon atoms of the alkane chain are substituted with N, O, S or P, the alkane chain terminates with a C1-C3 alkyl group, and the optional branching group is a C1-C3 alkyl group; 10 alkane chains; and Optionally branched C2-C 20 an alkane chain, one or more carbon atoms of which may be optionally substituted with N, O, S, or P, the alkane chain terminating in an acrylate group (-O-C(=O)-CH=CH2) or a methacrylate group (-O-C(=O)-C(CH3)=CH2), and the optional branching group is a C1-C3 alkyl group; 20 Alkane chain.

[0092] In an embodiment of the monomer of formula (III), R 11 is H and R 12 is selected from the group consisting of: [ka] Here, Cy is a cycloalkyl group having 3 to 7 ring carbon atoms.

[0093] In one embodiment of the monomer of formula (III), R 11 is a C1-C3 alkyl group, and R 12 is selected from the group consisting of: [ka] where Cy is a cycloalkyl group having 3 to 7 ring carbons (including cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl).

[0094] The monomer of formula (III) may be present in an amount of 1 to 30% by weight, such as 1 to 25% by weight, for example 5 to 25% by weight, such as 5 to 20% by weight, for example 10 to 25% by weight, for example 10 to 20% by weight, based on the total composition.

[0095] Reinforcement material The reinforcing material (also called filler) is not particularly limited, and examples of the reinforcing material include carbon fiber, plant fiber, wood fiber, mineral fiber, glass fiber, metal wire, etc. It should be noted that the expression "reinforcing material" is intended to encompass both structural and non-structural type materials.

[0096] In one embodiment, the reinforcing material is opaque. The term "opaque" as used in this disclosure with respect to the reinforcing material should be understood to mean a material that blocks all or substantially all radiation across the ultraviolet (UV) and visible wavelengths. In another embodiment, the reinforcing material is light scattering.

[0097] Those skilled in the art will recognize that a particular filler may be opaque to UV light or transparent to UV light, depending on factors such as its physical form or method of synthesis. Mixtures of two or more fillers are within the scope of the present invention, including embodiments of the present invention having some opaque fillers and some transparent fillers and / or some partially transparent fillers. Those skilled in the art will recognize that a particular filler may be opaque to UV light, transparent to UV light, or partially transparent to UV light, depending on factors such as its physical form or method of synthesis. Mixtures of two or more fillers are within the scope of the present invention.

[0098] Exemplary opaque fillers include chopped or continuous carbon fibers available in any conventional form such as tow, braid, unidirectional, woven fabric, knitted fabric, swirl fabric, felt mat, wound fabric, etc. Such carbon fibers are typically based on polyacrylonitrile or pitch systems.

[0099] The carbon fibers may be surface treated with plasma, nitric or nitrous acids, or similar strong acids, and / or may be further surface functionalized (often referred to as "size treatment" or "sizing") with agents such as, but not limited to, dialdehyde, epoxy, vinyl, and other functional groups that will enhance the adhesion of the carbon fibers to the cured polymer matrix.

[0100] Non-limiting examples of other UV opaque fillers include carbon black, graphite, graphite felt, graphite foam, graphene, resorcinol-formaldehyde blends, polyacrylonitrile, rayon, petroleum pitch, natural pitch, resoles, carbon nanotubes, carbon soot, creosote, SiC, boron, WC, butyl rubber, boron nitride, fumed silica, nanoclay, silicon carbide, boron nitride, zirconium oxide, titanium dioxide, chalk, calcium sulfate, barium sulfate, calcium carbonate, silicates such as talc, mica or kaolin, silica, aluminum hydroxide, magnesium hydroxide, or organic fillers such as polymer powders, polymer fibers, and the like, and mixtures thereof.

[0101] The reinforcing material can include or consist of continuous fibers. In this disclosure, "continuous" means that the aspect ratio (V), defined as the length l divided by the diameter d (l / d), is greater than 100, 100, 3500, 1,000,000, or more. The reinforcing material may include chopped fibers, i.e., fibers having an aspect ratio less than that of continuous fibers, and may be in any suitable shape or form. For example, the reinforcing material may be in the form of powder, beads, microspheres, particles, granules, wires, fibers, or combinations thereof. When in particulate form, the particles may be spherical, flat, irregular, or elongated. For example, high-aspect-aspect granular materials may be used. Hollow and solid materials are useful in the present invention. According to various embodiments of the present invention, the material may have an aspect ratio (i.e., the ratio of the length of an individual filler element, such as a particle or fiber, to the width of that individual filler element) of 1:1 or greater, for example, greater than 1:1, at least 2:1, at least 3:1, at least 5:1, at least 10:1, at least 100:1, at least 1000:1; at least 10,000:1, at least 100,000:1, at least 500,000:1, at least 1,000,000:1, or even higher aspect ratios (i.e., virtually infinite aspect ratios). According to other embodiments, the reinforcement may have an aspect ratio of 2:1 or less, 3:1 or less, 5:1 or less, 10:1 or less, 100:1 or less, 1000:1 or less; 10,000:1 or less, 100,000:1 or less, 500,000:1 or less, or 1,000,000:1 or less.

[0102] The surface of the reinforcing material may be modified according to any method or technique known in the art, including, but not limited to, sizing (e.g., coating with one or more organic substances), silylation, oxidation, functionalization, neutralization, acidification, other chemical modifications, and the like, and combinations thereof.

[0103] The chemical nature of the reinforcing material can be varied and selected as desired to impart specific properties or characteristics to the product obtained by curing the photocurable composition. For example, the material can be inorganic or organic in nature. Hybrid organic / inorganic reinforcing materials can also be used. Carbon-based reinforcing materials (e.g., carbon fiber, carbon black, carbon nanotubes) and mineral-based materials can also be employed.

[0104] Reinforcing materials may include carbon fiber, glass fiber, fiberglass, natural fiber (kenaf fiber), Twaron fiber, Dyneema fiber, ceramic fiber, asbestos, Kevlar fiber, polybenzimidazole fiber, polysulfonamide fiber, polyphenylene oxide fiber, plant fiber, wood fiber, mineral fiber, plastic fiber, metal wire, and / or aramid fiber. Carbon fiber is preferred, with continuous carbon fiber being most preferred. The carbon fiber or other fiber(s) may be surface treated (plasma) or "sized" with a suitable coupling agent, such as nitric acid, glutaric dialdehyde, or silane. The carbon fiber, polyacrylonitrile fiber, or rayon fiber may be straight or woven and may have various fiber diameters and densities. The fiber or co-fiber may have a varying fiber volume fraction, such as 20-90%, for example 25-80%, for example 30-75%, for example 30-70%. Blends of fibers, whether continuous or chopped, are contemplated, for example, carbon fibers may be commercialized in combination with ceramic fibers, asbestos fibers, Kevlar fibers, polybenzimidazole fibers, polysulfonamide fibers, glass fibers, vegetable fibers, wood fibers, mineral fibers, plastic fibers, metal wire, and / or aramid fibers.

[0105] A typical resin type used in Kevlar ballistic armor is a BPA-epoxy blend with an amine curing agent. Neat resin properties include an average Tg range of 1-285°C, an average tensile strength range of 1-2900 MPa, and an average flexural strength range of 76-1890 MPa. In one embodiment, the Tg is 120-130°C, the tensile strength is 85 MPa, and the flexural strength is 112 MPa.

[0106] Particulate reinforcing materials may be included, non-limiting examples of which include graphite, ceramics (including high temperature ceramics such as SiC / boron), nanosilica, boron nitride, nanoclay, carbon soot, fly ash, coke, carbon, graphite, glassy carbon, amorphous carbon, pitch, non-graphitic powders, carbon black, and mixtures thereof.

[0107] The reinforcing material may comprise particles and may be present in an amount of at least 0.50% by weight of the curable composition before curing. For example, the actinic radiation curable composition may comprise at least 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or at least 90% by weight of particulate filler. When present, particulate filler is preferably present in an amount of up to 1% by weight.

[0108] The reinforcing material may comprise fibers and may be present in an amount of at least 0.50% by weight of the curable composition before curing. For example, the actinic radiation curable composition may comprise at least 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or at least 90% by weight of fibers.

[0109] The reinforcing material may comprise continuous fibers and may be present in an amount of at least 0.50% by weight of the curable composition before curing. For example, the actinic radiation curable composition may comprise at least 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or at least 90% by weight of continuous fibers.

[0110] The reinforcement may comprise continuous carbon fiber and may be present in an amount of at least 0.50% by weight of the curable composition before curing. For example, the actinic radiation curable composition may comprise at least 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or at least 90% by weight of continuous carbon fiber.

[0111] Other additives The curable composition may contain additives, including, but not limited to, antioxidants, ultraviolet absorbers, light stabilizers, antifoaming agents, flow or leveling agents, colorants, pigments, dispersants (wetting agents), lubricants, impact modifiers, matting agents, thermoplastic resins, waxes, or various additives that do not contain free-radically polymerizable functional groups, such as additives commonly used in coatings, sealants, adhesives, and molding or ink applications.

[0112] Suitable impact modifiers include ethylene / propylene copolymers, which may optionally contain a third copolymerizable diene monomer, such as 1,4-hexadiene, dicyclopentadiene, dicyclooctadiene, methylene norbornane, ethylidene norbornane, and tetrahydroindene. Other suitable impact modifiers are polybutadiene, polyisoprene, styrene / butadiene random copolymers, styrene / isoprene random copolymers, acrylic rubbers (e.g., polybutyl acrylate), ethylene / acrylate random copolymers and acrylic block copolymers, styrene / butadiene / (meth)acrylate (SBM) block copolymers, styrene / butadiene block copolymers (styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS) and their hydrogenated products, SEBS, SEPS), and (SIS), as well as ionomers. Commercially available examples of elastomers are Kraton (SBS, SEBS, SIS, SEBS, and SEPS) block copolymers from Shell, LOTRYL® ethyl / acrylate random copolymers from Arkema, and Surlyn ionomers from Dupont. Optionally, the elastomers may be modified to include reactive groups, such as epoxy, oxetane, carboxyl, or alcohol. This modification can be introduced by reactive grafting or copolymerization. Commercially available examples of the latter include LOTADER® random ethylene / acrylate copolymers AX8840 (glycidyl methacrylate / GMA modified), AX8900, and AX8930 (GMA and maleic anhydride modified / MA) from Arkema.

[0113] In one embodiment, the curable composition includes a peroxide and / or azo-based thermal initiator that decomposes when heated and is therefore also chemically curable (i.e., in addition to exposing the curable composition to radiation). Suitable peroxides include any compound containing at least one peroxy (—OO—) moiety, particularly any organic compound, such as dialkyl, diaryl, and aryl / alkyl peroxides, hydroperoxides, percarbonates, peresters, peracids, acyl peroxides, and the like. The at least one accelerator may include, for example, at least one tertiary amine and / or one or more other reducing agents based on metal-containing salts (e.g., carboxylates of transition metal-containing salts of iron, cobalt, manganese, vanadium, and the like, and combinations thereof). The accelerator(s) may be selected to promote decomposition of the free radical initiator to generate active free radical species at room or ambient temperature, such that cure of the curable composition is achieved without the need to heat or bake the curable composition. In other embodiments, no accelerator is present, and the curable composition is heated to a temperature effective to cause decomposition of the free radical initiator, generating free radical species that initiate curing of the polymerizable compound(s) present in the curable composition. Without being bound by theory, according to some embodiments, the exotherm provided by the photoinduced polymerization provides sufficient heat to decompose such chemical (thermal) free radical initiators.

[0114] The concentration of thermal initiator in the actinic radiation-curable compositions described herein can be varied as desired, depending on, among other factors, the individual compound(s) selected, the type of polymerizable compound(s) present in the actinic radiation-curable composition, the curing conditions utilized, and the desired cure rate. Typically, however, the actinic radiation-curable composition may further comprise 0.05% to 5%, preferably 0.1% to 2%, by weight of thermal initiator, based on the total weight of the curable composition excluding the reinforcing material. According to some embodiments, a typical concentration of thermal initiator can be up to about 15% by weight, based on the total weight of the curable composition excluding the reinforcing material. For example, the actinic radiation-curable composition may comprise a total of 0.1 to 10% by weight of thermal initiator, based on the total weight of the curable composition excluding the reinforcing material.

[0115] In one particular embodiment, the peroxide is benzoyl peroxide and the azo thermal initiator is 2,2'-azobis(isobutyronitrile) (AIBN).

[0116] The curable composition may optionally include one or more thickeners (also known as viscosity modifiers, thickeners, or viscosifiers), which help adjust the viscosity of the composition, can act as plasticizers, can improve material properties by increasing strength or impact resistance, etc. Thickeners suitable for the composition can be selected that are miscible with the monomers with which they are combined. Thickeners are well known in the art and can be, for example, poly(meth)acrylates, acylated cellulose polymers (e.g., cellulose acetate, cellulose acetate propionate), polyvinyl acetate, partially hydrolyzed polyvinyl acetate, polyvinylpyrrolidone, polyoxylates, polycaprolactone, polycyanoacrylates, vinyl acetate copolymers (e.g., copolymers with vinyl chloride), copolymers of (meth)acrylates with butadiene and styrene, copolymers of vinyl chloride and acrylonitrile, copolymers of ethylene and vinyl acetate, poly[butylene terephthalate-co-polyethylene glycol terephthalate], and copolymers of lactic acid and caprolactone. Such polymeric thickeners can be distinguished from reinforcing materials by the fact that they are generally soluble in the photocurable resin component of the photocurable composition, as well as in the polymer matrix formed when the photocurable resin component is cured. However, it has been recognized that some of the materials taught in this disclosure as reinforcing agents may also function to some extent as thickeners while remaining insoluble in the photocurable resin component.

[0117] According to certain embodiments, the curable composition includes a thickener in an amount of up to 15%, up to 12%, or up to 10% by weight, based on the weight of the curable composition excluding the reinforcement component. For example, the curable composition may include at least 0.1%, at least 0.5%, or at least 1% by weight, based on the weight of the curable composition excluding the reinforcement component, of a thickener. The curable composition may also include a thixotropic agent to adjust its flow behavior. The thixotropic agent can be organic or inorganic, and in certain embodiments, is selected from the group consisting of hydrogenated castor oil, hydrogenated castor oil modified by reaction with an amine, polyamide, and silica (e.g., hydrophobic fumed or precipitated silica). However, when a thixotropic agent is present, its concentration is typically limited to 5% by weight or less, based on the total weight of the curable composition.

[0118] Additive Manufacturing Methods The curable composition can be prepared by any suitable method, including simply combining the various desired components in the desired proportions. According to certain embodiments of the present invention, the curable resin component of the curable composition is prepared and stored separately from the reinforcement component, and then the two components are combined to form the photocurable composition immediately before or simultaneously with curing of the curable composition. The curable resin component and the curable composition are preferably stored in packaging that is shielded from light having wavelengths effective to initiate curing of the curable resin component or the curable composition. For example, the package or container can be shielded from light of wavelengths between 300 nm and 750 nm. It is also preferable to select the interior surface of the package or container to be suitable for maintaining the curable composition in a stable, uncured form over an extended shelf life. For example, the interior surface of the package or container can be constructed of a low-energy surface plastic or passivated glass or metal.

[0119] The curable compositions are useful for preparing composite materials by photocuring the curable resin component to form a polymer matrix. The cured polymer matrix encapsulates and binds the reinforcing component of the curable composition. The reinforcing component serves to improve the mechanical properties compared to the chemical properties of the cured polymer matrix obtained by curing the photocurable resin component in the absence of a filler component. For example, when the reinforcing material is in the form of fibers, photocuring the curable compositions of the present invention can result in a fiber-reinforced composite material.

[0120] Generally, a composite material can be defined as any material containing a reinforcing material supported by a binder material. Thus, a composite material can include a two-phase material having a discontinuous reinforcing material phase that is stiffer and / or stronger than the continuous binder (matrix) phase. In the context of composite materials prepared according to the present invention, the reinforcing material can function as a stiffening agent, while the polymer matrix formed by photocuring the photocurable resin component of the photocurable composition can function as a binder material.

[0121] The curable compositions of the present invention can be used as coatings, adhesives, sealants, potting compounds, encapsulants, and other such products, but are particularly useful for bulk curing and for the fabrication of bulk objects or monoliths by photocuring.

[0122] Methods for curing the photocurable compositions of the present invention using photoirradiation can include irradiating the curable composition with electron beam, ultraviolet light, visible light, or near-infrared light using any suitable radiation source, such as a long-wave ultraviolet lamp, a low-intensity arc lamp, a high-intensity arc lamp, a high-pressure mercury lamp, a halogen lamp, a light-emitting diode (LED), a xenon lamp, or sunlight.

[0123] Generally, ultraviolet (UV) and visible light are preferred, with the effective wavelength of the irradiated light varying depending on the particular photoinitiator system used and / or the photodegradable compounds present in the photoinitiator system.

[0124] Therefore, the light source used should provide light in the wavelength range dictated by the particular photoinitiator system being used. Ideally, the wavelength of light emitted from the light source (e.g., an LED) should be tightly coupled to the absorption of the photoinitiator system of the photocurable resin composition. Although not required, light with wavelengths outside the desired photopolymerization range for the particular photoinitiator system may be filtered out. Additionally, the light source used can emit light that is transmitted through one or more faces or sides of the composite part being produced.

[0125] According to certain embodiments of the present invention, the curable composition can be formulated to be cured by exposure to light having a wavelength of 350 nm to 490 nm, or 365 nm to 465 nm, or 380 nm to 410 nm. The light intensity can be, for example, 20 mW / cm. 2 ~150mW / cm 2 , or 40 mW / cm 2 ~90mW / cm 2 The curable composition may be stationary when exposed to light. Alternatively, the curable composition may be moving (e.g., on a conveyor belt) when exposed to light. The portion of the photocurable composition that is photocured in accordance with the present invention to form a composite or article may be irradiated with light from one direction or from multiple directions. However, one distinct advantage of the present invention is that irradiation with light from only one direction can be effective to cause complete curing of the curable composition throughout the composite or article, despite the presence of reinforcing materials that can block the transmission of the incident light or that can scatter the incident light so that the light does not reach all areas of the photocurable resin component within the composition.

[0126] Various techniques can be used to form composite articles using the photocurable compositions of the present invention. For example, a mold for the desired composite article can be employed, having at least one surface or side transparent to the initiating light to allow sufficient light transmission for photocuring to occur, a suitable light source, and the desired photocurable composition itself in an amount sufficient to fill the mold. The specific order of steps actually used can be varied as desired. For example, the mold can be filled either before or after the light source used is turned on. The photocurable composition can also be introduced into the mold in a combined form. For example, the reinforcing material(s) can be dispersed in the remaining components of the curable composition, and the resulting mixture can be filled into the mold. However, the reinforcing material(s) can also be introduced into the mold separately from the other components of the curable composition. For example, the reinforcing material when introduced into the mold can be a preform, such as a fiber mat (woven or non-woven). According to one embodiment, the reinforcement component when introduced into the mold may be pre-wetted or pre-impregnated with a quantity of a liquid mixture of the other components of the curable composition, and an additional amount of such mixture is then introduced into the mold to combine with the pre-wetted reinforcement component. It is also possible to form structured or layered composite articles, which may be characterized by having one or more regions or layers that contain little or no filler and one or more regions or layers that contain a relatively high concentration of reinforcement.

[0127] One distinct advantage of the present invention is that it allows for the efficient production of relatively thick composite articles despite the presence of a significant amount of reinforcing material that blocks or scatters light. For example, in certain embodiments, the thickness of the composite articles produced can be in the range of about 0.1 centimeters to about 10 centimeters, or even greater. While the present invention is highly useful for forming composite articles in this thickness range, the present invention is equally operable for forming composite articles that are significantly thicker than the 0.1-10 centimeter range.

[0128] However, the photocurable compositions of the present invention are also suitable for forming relatively thin composite films or coatings. Such cured composite films and coatings may have thicknesses of, for example, at least 10 microns, at least 50 microns, or at least 100 microns, up to 0.5 mm or 1 mm. Within the scope of the present invention, articles can also be constructed layer by layer using the photocurable compositions, for example, by forming and exposing a first thin layer of the photocurable composition having a thickness of 10 microns to 500 microns, then depositing and exposing a second thin layer of the photocurable composition on the first thin layer, followed by depositing and exposing one or more subsequent thin layers of the photocurable composition, each of which is also exposed before depositing the next thin layer.

[0129] It should be understood that the present invention can be used to form any article, shape, or part for any application. By "article" is meant a three-dimensional shape configured for an intended application. The present invention can also be used to produce composite articles, one or more portions of which are composed of a composite material obtained by curing a curable composition according to the present invention and one or more portions of a material not derived from the curable composition (e.g., metal, ceramic, plastic). For example, a composite article can include a substrate of a first material (not derived from the curable composition according to the present invention) having at least one surface in contact with (e.g., adhered or bonded to) a composite material according to the present invention. The curable compositions of the present invention can also be used to make useful articles by methods such as additive manufacturing (including three-dimensional (3D) printing) and pultrusion. Such methods can be moldless and / or out-of-autoclave (OOA) processes. Suitable 3D printing systems include stereolithography (SLA), digital light processing (DLP), hot lithography, and continuous liquid interface manufacturing (CLIP). As an example, a dispensing head equipped with a light source can be used to impregnate fiber strands or tows with a photocurable resin component (consisting of the components of the photocurable composition of the present invention, excluding the fibers) to form a curable composition within the dispensing head, and then the curable composition can be cured using light immediately after material deposition to provide a cured composite material. In this manner, three-dimensional composite articles containing oriented reinforcing fibers can be made without a mold or other support material.

[0130] Some well-known ASTM standards related to 3D printing include: [Table 1]

[0131] The photocurable compositions of the present invention are also suitable for use in automated fiber placement (AFP) and automated tape layup (ATL) processes.

[0132] While the photocurable composition is exposed to light in a manner effective to initiate curing, the curable composition is preferably at about room temperature (e.g., from about 10°C to about 35°C). However, it is also possible to maintain the curable composition at an elevated temperature (e.g., greater than 35°C to about 100°C) while it is exposed to light. If desired, the composite article thus produced can be subjected to post-photocuring operations. For example, thermal curing in a heated oven can be used.

[0133] The curable compositions of the present invention can also be used as inks (for graphic arts applications, including food packaging), molding resins, 3D printing resins, coatings (such as fiber coatings), and sealants and adhesives (e.g., UV-curable laminating adhesives, UV-curable hot melt adhesives, etc.).

[0134] The curable compositions prepared from the curable compositions described herein can be, for example, a three-dimensional object (wherein the three-dimensional object can consist essentially of the cured composition), a coated article (i.e., one of the substrates is coated with one or more layers of the cured composition), a laminated or bonded article bonded or adhered to a second component (i.e., one of the first components is overlaid with the cured composition), or a printed article (wherein the curable composition is used to print graphics or the like onto a substrate such as paper, plastic, or metal substrate).

[0135] Before curing, the curable composition can be applied to a substrate by any known conventional means, such as spray coating, knife coating, roll coating, casting, drum coating, dip coating, and combinations thereof. Indirect coating using a transfer method can also be used. The substrate can be any commercially relevant substrate, such as a high-surface energy substrate or a low-surface energy substrate, such as a metal substrate or a plastic substrate, respectively. Substrates include metal, paper, cardboard, glass, thermoplastics such as polyolefins, polycarbonate, acrylonitrile butadiene styrene (ABS) and blends thereof, composites, wood, leather, and combinations thereof. When used as an adhesive, the curable composition can be placed between two substrates and then cured, whereby the cured composition bonds the substrates.

[0136] Multiple layers of a composition according to the present invention can be applied to a substrate surface and the multiple layers can be cured simultaneously (e.g., by exposure to radiation in a single dose) or the layers can be cured sequentially before coating another layer of the composition.

[0137] The curable compositions described herein are particularly useful as 3D printing resin formulations, i.e., compositions intended for producing three-dimensional objects using 3D printing techniques. Such three-dimensional objects can be freestanding / self-supporting and can consist essentially of the cured curable compositions. Alternatively, the three-dimensional objects can consist essentially of the cured compositions, or can be composites that include at least one component consisting of the cured compositions and at least one additional component of one or more materials (e.g., a metal component or a thermoplastic component).

[0138] A method for producing a three-dimensional object using a curable composition according to the present invention may comprise the following steps: a) applying a first layer of the curable composition according to the present invention to a surface; b) curing the first layer to provide a cured first layer; c) applying a second layer of curable composition to the cured first layer; d) curing the second layer to provide adhesion of the cured second layer to the cured one of the first layers; and e) repeating steps c) and d) as necessary to build a three-dimensional object.

[0139] In some embodiments of the present invention, curing of the curable composition is achieved by exposing the curable composition to an effective amount of radiation (eg, electron beam radiation, ultraviolet light, visible light, etc.).

[0140] Thus, in various embodiments, the present invention provides a method comprising the steps of: a) applying a first layer of the curable composition according to the invention in liquid form onto a surface; b) exposing the first layer to actinic radiation to form a first exposed imaging cross section, wherein the actinic radiation is of sufficient intensity and duration to at least partially cure (e.g., at least 80% or at least 90% cure) the layer in the exposed areas; c) applying an additional layer of curable composition to the previously exposed imaged cross section; d) exposing the additional layer to actinic radiation in an imagewise manner to form a further imaged cross section, wherein the actinic radiation is of sufficient intensity and duration to at least partially cure (e.g., at least 80% or at least 90% cure) the additional layer in the exposed areas and to adhere the additional layer to the previously exposed imaged cross section; and e) Repeating steps c) and d) as necessary to build a three-dimensional object.

[0141] The method of using the curable composition in making three-dimensional printed articles using conventional 3D printing techniques is not particularly limited, and includes digital light projection, stereolithography, and multi-jet and binder jet printing.

[0142] In one embodiment of a curable composition containing continuous fibers as reinforcement, continuous fiber 3D printing (commonly known as CF3D®) is a preferred method. CF3D® involves the use of continuous fibers embedded in a material ejected from a movable print head. A matrix is ​​fed into the print head and simultaneously ejected (e.g., extrusion and / or pultrusion) through the same head along with one or more continuous fibers. The matrix can be a traditional thermoplastic resin, a liquid thermosetting resin (e.g., a UV-curable resin and / or a two-part resin), or a combination of any of these with other known matrices. Upon exiting the print head, a cure enhancer (e.g., ultraviolet light, laser, ultrasound emitter, heat source, catalyst supply, etc.) is activated to initiate, accelerate, and / or complete the curing of the matrix. This curing occurs almost instantly, allowing the creation of structures that are unsupported in free space. When fibers, especially continuous fibers, are embedded within a structure, the strength of the structure can be multiplied beyond that dependent on the matrix. An example of this technology is disclosed in US Pat. No. 9,511,543.

[0143] In one embodiment of curing, a method of curing the curable composition comprises exposing the curable composition to actinic radiation sufficient to cure the curable composition.

[0144] In one embodiment, a method for producing a three dimensional printed composite article includes: ejecting an actinic radiation curable composition from a printhead, wherein the actinic radiation curable composition includes a reinforcing material; moving the print head during ejection of the actinic radiation curable composition; and Irradiating the actinic radiation curable composition with light to form a cured three-dimensional printed composite article.

[0145] In another embodiment, a method of making a three-dimensionally printed carbon-bonded composite article using Continuous Fiber 3D (CF3D®) includes: Irradiating the actinic radiation curable composition in the presence of continuous carbon fibers to form a cured three-dimensional printed carbon-bonded composite article.

[0146] In various embodiments, the curable composition is applied as a single deposit.

[0147] In various embodiments, the cured composite article has low optical clarity.

[0148] In one embodiment, the printhead contains the curable composition.

[0149] Certain non-limiting aspects of the present invention are summarized below: Aspect 1. An actinic radiation curable composition comprising: (a) 20 to 80% by mass of acrylamide or methacrylamide that satisfies the following criteria: (1) an average dipole moment of 2.5 or more; (2) a hydrogen atom, a methyl group, or a methylene group is present at the α-position relative to the nitrogen atom of the acrylamide or methacrylamide, and a hydrogen atom, a methyl group, a methylene group, a methine group, a heteroatom, or an aromatic group is present at the β-position relative to the nitrogen atom; and (3) one molecule of acrylamide or methacrylamide has two or more heteroatoms; (b) 10 to 60% by weight of at least one monomer of formula (II); [ka] (c) 0 to 30% by mass of a urethane (meth)acrylate oligomer; and (d) 0.1 to 5 mass% of a photoinitiator; where R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where at least two of R7, R8 and R9 are -(CH2) n O(C=O)-CR 10 =CH2; R 10is selected from the group consisting of H and C1-C3 alkyl; n is 1, 2, 3 or 4.

[0150] Embodiment 2. An actinic radiation curable composition comprising: (a) 20 to 80% by weight of at least one monomer of formula (I): [ka] (b) 10 to 60% by weight of at least one monomer of formula (II): [ka] (c) 0 to 30% by mass of a urethane (meth)acrylate oligomer; and (d) 0.1 to 5 mass% of a photoinitiator; where: R1 is H or C1-C3 alkyl; R2 and R3 are H, C1-C3 alkyl, CH2-CH(OH)C1-C3 alkyl and (CH2) m X, each independently selected from the group consisting of or R2 and R3 together with the nitrogen atom to which they are attached form a 3- to 6-membered saturated heterocyclic ring; X is OR4, SR4, NR5R6, or an aromatic group; R4 is selected from the group consisting of H and C1-C4 alkyl; R5 and R6 are each independently selected from the group consisting of H and C1-C3 alkyl; m is 1, 2, 3, 4 or 5; R7, R8 and R9 each independently represent -(CH2) n O(C=O)-CR 10 =CH2 or H, where: At least two of R7, R8 and R9 are -(CH2) n O(C=O)-CR 10 =CH2; R 10 is selected from the group consisting of H and C1-C3 alkyl; n is 1, 2, 3 or 4.

[0151] Aspect 3. The curable composition of Aspect 2, wherein for the monomer of Formula (I), R1 is H, and R2 and R3, together with the nitrogen atom to which they are attached, form a 5- or 6-membered saturated heterocyclic ring.

[0152] Aspect 4. For the monomer of formula (II), at least one of R7, R8, and R9 is (CH2) n O(C=O)-CR 10 Aspect 4. The curable composition of any one of aspects 1 to 3, wherein =CH2, where n is 2.

[0153] Embodiment 5. For the monomer of formula (II), at least two of R7, R8, and R9 are (CH2) n O(C=O)-CR 10 Aspect 4. The curable composition of any one of aspects 1 to 3, wherein =CH2, where n is 2.

[0154] Aspect 6. For the monomer of formula (II), at least one of R7, R8, and R9 is (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 Aspect 4. The curable composition of any one of Aspects 1 to 3, wherein is H.

[0155] Aspect 7. For monomers of formula (II), at least two of R7, R8, and R9 are (CH2) n O(C=O)-CR 10 =CH2, where n is 2, and R 10 Aspect 4. The curable composition of any one of Aspects 1 to 3, wherein is H.

[0156] Aspect 8. The curable composition of any one of Aspects 2-7, wherein the acrylamide / methacrylamide or monomer of Formula (I) is selected from the group consisting of: [ka]

[0157] Embodiment 9. The curable composition of any one of Embodiments 2-8, wherein the monomer of Formula (I) is acryloylmorpholine (ACMO): [ka]

[0158] Aspect 10. The curable composition of any one of Aspects 2-9, wherein the monomer of Formula (II) is tris(2-hydroxyethyl)isocyanurate triacrylate (M370): [ka]

[0159] Embodiment 11. The monomer of formula (I) is ACMO: [ka] and the monomer of formula (II) is M370: [ka] 11. The curable composition according to any one of Aspects 2 to 10, wherein

[0160] Aspect 12. The curable composition according to any one of Aspects 1 to 11, further comprising a reinforcing material (filler).

[0161] Aspect 13. The curable composition of any one of Aspects 1 to 12, wherein the reinforcing material is an opaque reinforcing material (opaque filler) or a light-scattering reinforcing material.

[0162] Embodiment 14. The curable composition of any one of embodiments 1 to 13, wherein the opaque or light-scattering filler comprises continuous fibers.

[0163] Embodiment 15. The curable composition of any one of embodiments 1-14, wherein the opaque filler comprises continuous carbon fibers.

[0164] Embodiment 16. The curable composition of any one of embodiments 1 to 15, wherein the reinforcing material is selected from the group consisting of glass, fiberglass, chopped carbon fiber, continuous carbon fiber, and Kevlar®, and optionally, one or more of nylon, polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), and polycarbonate are present.

[0165] Embodiment 17. The curable composition of any one of embodiments 1-16, wherein the reinforcing material is not glass.

[0166] Aspect 18. The curable composition of any one of Aspects 1 to 17, wherein the reinforcing material is glass fiber or continuous carbon fiber.

[0167] Aspect 19. The curable composition of any one of Aspects 1 to 18, wherein the urethane (meth)acrylate oligomer is selected from the group consisting of PHOTOMER® 6008, PHOTOMER® 6010, PHOTOMER® 6019, PHOTOMER® 6184, PHOTOMER® 6630, and PHOTOMER® 6892.

[0168] Aspect 20. The curable composition of any one of Aspects 1 to 19, wherein the photoinitiator is selected from the group consisting of benzophenones, benzoin ethers, benzil ketals, α-hydroxyalkylphenones, α-alkoxyalkylphenones, α-aminoalkylphenones, and acylphosphines.

[0169] Aspect 21. The photoinitiator is selected from the group consisting of 1-hydroxy-cyclohexyl-phenyl-ketone (IRGACURE® IC-184); 2,4,6-trimethylbenzoyldiphenylphosphine oxide (LUCIRIN® TPO); 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (LUCIRIN® TPO-L); bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide (IRGACURE® 819); 2-methyl-1-(4-methylthio)phenyl-2-(4-morpholinyl)-1-propanone (IRGACURE® 907), and 1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one (IRGACURE® 908). 2959); 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (IRGACURE® 369); 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)-benzyl)-phenyl)-2-methylpropan-1-one (IRGACURE® 127); and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (IRGACURE® 379).

[0170] Aspect 22. The curable composition of any one of Aspects 1 to 22, further comprising an acrylate or methacrylate that meets the following criteria: (1) an average dipole moment of 2.5 or greater; (2) a methyl or methylene group at the alpha position relative to the oxygen atom of the acrylate or methacrylate, and a hydrogen, methyl, methylene, methine, heteroatom, or aromatic group at the beta position relative to the oxygen atom; and (3) three or more heteroatoms per acrylate molecule and four or more heteroatoms per methacrylate molecule.

[0171] Aspect 23. The curable composition of any one of Aspects 2 to 22, wherein the curable composition further comprises a monomer of formula (III): [ka] where: Each R 11 are independently H or C1-C3 alkyl; R 12 is selected from the group consisting of: R 11 is H, then R 11 is CH3, a heterocycle containing at least two of N, O or S; A C2-C6 alkylene chain, R 11 is H, at least one carbon atom of the alkylene chain is replaced with N, O, or S, and the alkylene chain terminates with a C1-C3 alkyl group; A C2-C6 alkylene chain, R 11 is CH3, a C2-C6 alkylene chain in which at least two carbon atoms of the alkylene chain are replaced by N, O, or S, and the alkylene chain terminates with a C1-C3 alkyl group; and A C2-C6 alkylene chain, wherein one or more carbon atoms of the alkylene chain may be optionally replaced by N, O, or S, and the alkylene chain terminates in an acrylate group (-O-C(=O)-CH=CH2) or a methacrylate group (-O-C(=O)-C(CH3)=CH2).

[0172] Aspect 24. For the monomer of formula (III), R 11 is H and R 12 The curable composition of any one of aspects 2 to 23, wherein is selected from the group consisting of: [ka] Here, Cy is a cycloalkyl group having 3 to 7 ring carbon atoms.

[0173] Aspect 25. For a monomer of formula (III), R 11 is CH3 and R 12 The curable composition of any one of aspects 2 to 24, wherein is selected from the group consisting of: [ka] Here, Cy is a cycloalkyl group having 3 to 7 ring carbon atoms.

[0174] Embodiment 26. The curable composition of any one of embodiments 1 to 25, wherein the curable resin further comprises a peroxide.

[0175] Embodiment 27. The curable composition of any one of Embodiments 1 to 26, wherein the curable resin further comprises an azo-based thermal initiator.

[0176] Embodiment 28. A method for curing the curable composition of any one of embodiments 1 to 27, comprising exposing the curable composition to actinic radiation sufficient to cure the curable composition.

[0177] Embodiment 29. A method for producing a three-dimensional printed composite article, the method comprising: ejecting from a print head an actinic radiation curable composition of any one of embodiments 1-27, wherein the actinic radiation curable composition comprises a reinforcing material; moving the print head during ejection of the actinic radiation curable composition; and Irradiating the actinic radiation curable composition with light to form a cured three-dimensional printed composite article.

[0178] Embodiment 30. A method of producing a three-dimensionally printed carbon-bonded composite article using Continuous Fiber 3D (CF3D®), comprising: irradiating an actinic radiation curable composition of any one of aspects 1-27 in the presence of continuous carbon fibers to form a cured three-dimensional printed carbon-bonded composite article; A method comprising:

[0179] Embodiment 31 The method of any one of Embodiments 28-30, wherein the curable composition is applied as a single deposit.

[0180] Embodiment 32 The method of any one of embodiments 28-30, wherein the cured composite article has low optical clarity.

[0181] Embodiment 33 The method of any one of embodiments 28-30, wherein the print head contains a curable composition.

[0182] Although embodiments are described herein to enable a clear and concise specification to be written, it is intended, and will be understood, that the embodiments can be combined or separated in various ways without departing from the invention. For example, it will be understood that all preferred features described in this disclosure are applicable to all aspects of the invention described in this disclosure.

[0183] In some embodiments, the invention in this disclosure can be construed to exclude any element or process step that does not materially affect the basic and novel characteristics of the actinic radiation curable compositions, methods for making actinic radiation curable compositions, methods for using actinic radiation curable compositions, and articles made from actinic radiation curable compositions. Further, in some embodiments, the invention can be construed to exclude any element or process step not specified in this disclosure.

[0184] Although the invention has been illustrated and described in this disclosure with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various changes in the details may be made within the scope and range of equivalents of the claims without departing from the invention. [Example]

[0185] Example 1. Manufacturing process FIG. 1 illustrates an exemplary system 10 that can be used to fabricate a composite material structure 12 having any desired shape, size, configuration, and / or material composition. The system 10 may include at least a support 14 and a head 16. The head 16 may be coupled to and movable by the support 14 during dispensing of the composite material (shown as C). In the disclosed embodiment of FIG. 1 , the support 14 is a robotic arm that can move the head 16 in multiple directions during fabrication of the structure 12, such that the longitudinal axis (e.g., trajectory) of the resulting dispensing is three-dimensional. The support 14 may alternatively embody a gantry (e.g., an overhead bridge gantry, a single-post gantry, etc.) or a hybrid gantry / arm that can move the head 16 in multiple directions during fabrication of the structure 12. While the support 14 is shown as capable of six-axis movement, it is contemplated that any other type of support 14 capable of moving the head 16 in the same or different manner may also be utilized. In some embodiments, a drive or coupling may include components that cooperate to mechanically couple the head 16 to the support 14, move portions of the head 16, and / or provide power and / or material to the head 16.

[0186] Head 16 may be configured to receive or otherwise contain a matrix, along with a continuous reinforcing material, that constitutes the composite material extruded from head 16. The matrix may include any type of curable material (e.g., a liquid resin such as a non-volatile organic compound resin, a powdered metal, etc.). Exemplary resins include thermosetting resins, one- or multi-part epoxy resins, polyester resins, cationic epoxy resins, acrylated epoxy resins, urethane resins, ester resins, thermoplastic resins, photopolymers, polyepoxides, thiols, alkenes, thiol-enes, etc. In one embodiment, the matrix within head 16 may be pressurized by an external device (e.g., an extruder or another type of pump—not shown) fluidly connected to head 16 via a corresponding conduit (not shown). However, in other embodiments, pressure may be generated throughout the interior of head 16 by a similar type of device. In still other embodiments, the matrix may be gravity-fed to and / or through head 16. For example, the matrix may be fed into head 16 and extruded or drawn out of head 16 along with one or more continuous reinforcing materials. In some cases, the matrix in head 16 may benefit from being kept cool and / or dark (e.g., to inhibit premature curing or otherwise achieve a desired cure rate after dispensing). In other cases, the matrix may need to be kept warm for similar reasons. In either situation, head 16 may be specially configured to accommodate these needs (e.g., thermal insulation, temperature control, shielding, etc.).

[0187] The matrix may be used to encase any number of continuous reinforcing materials (e.g., separate fibers, tows, rovings, socks, and / or sheets of continuous material) and, together with the reinforcing materials, construct a portion (e.g., a wall) of the composite structure 12. The reinforcing materials may be stored within the head 16 (e.g., in one or more separate internal creels—not shown) or may pass through the head 16 (e.g., supplied from one or more external spools—not shown). When multiple reinforcing materials are used simultaneously, the reinforcing materials may be of the same material composition, have the same size and cross-sectional shape (e.g., round, square, rectangular, etc.), or may have different material compositions and different sizes and / or cross-sectional shapes. Reinforcing materials include, for example, carbon fiber, plant fiber, wood fiber, mineral fiber, glass fiber, metal wire, etc. Note that the term “reinforcing material” is intended to encompass both structural and non-structural types of continuous material that are at least partially enclosed in the matrix discharged from the head 16.

[0188] The reinforcement material may be exposed to (e.g., at least partially coated with) the matrix while it is inside head 16, while it is being fed into head 16, and / or while it is being discharged from head 16. The matrix, dry reinforcement material, and / or reinforcement material already exposed to the matrix (e.g., pre-impregnated reinforcement material) may be conveyed into head 16 by any method apparent to one skilled in the art. In some embodiments, a filler material (e.g., chopped fiber) may be mixed with the matrix before and / or after the matrix coats the continuous reinforcement material.

[0189] As described in more detail below, one or more cure enhancers (e.g., ultraviolet light, ultrasonic emitters, lasers, heaters, catalyst dispensers, etc.) 18 may be mounted proximate to head 16 (e.g., within, on, or adjacent to head 16) and configured to enhance the rate and / or quality of cure of the matrix as it is dispensed from head 16. The cure enhancer(s) 18 can be controlled to selectively expose portions of structure 12 to energy (e.g., to ultraviolet light, electromagnetic radiation, vibration, heat, chemical catalysts, etc.) during material dispensing and formation of structure 12. The energy can induce chemical reactions occurring within the matrix, increase the rate of chemical reactions, sinter the matrix, harden the matrix, or otherwise harden the matrix as it is dispensed from head 16. The amount of energy generated by cure enhancer(s) 18 can be sufficient to harden the matrix before structure 12 grows axially from head 16 beyond a predetermined length. In one embodiment, the structure 12 is cured before the axial growth length equals the outer diameter of the matrix coated reinforcement.

[0190] The matrix and / or reinforcing material may be dispensed from the head 16 by at least two different modes of operation. In a first mode of operation, the matrix and / or reinforcing material is extruded (e.g., extruded under pressure and / or mechanical force) from the head 16 as the head 16 is moved by the support 14 to form a three-dimensional trajectory within the longitudinal axis of the dispensed material. In a second mode of operation, at least the reinforcing material is pulled from the head 16 such that a tensile stress is generated in the reinforcing material during dispensing. In this mode of operation, the matrix may adhere to the reinforcing material and thereby be pulled from the head 16 along with the reinforcing material, and / or the matrix may be dispensed from the head 16 under pressure with the tensioned reinforcing material. In the second mode of operation, in which the matrix is ​​dispensed from the head 16 along with the reinforcing material, the resulting tension in the reinforcing material may increase the strength of the structure 12 (e.g., by aligning the reinforcing material, inhibiting buckling, etc.) while allowing longer lengths of unsupported structure 12 to have straighter trajectories. That is, the tension in the reinforcement remaining after the matrix hardens can act against gravity (e.g., directly and / or indirectly by creating a moment that counteracts gravity) to provide support for the structure 12.

[0191] Reinforcement material may be pulled from head 16 as a result of head 16 being moved by support 14 away from anchor point 20 (e.g., print bed, table, floor, wall, surface of structure 12, etc.—not shown). In particular, at the beginning of structure formation, a length of matrix-impregnated reinforcement material may be pulled and / or extruded from head 16, deposited on anchor point 20, and at least partially cured, causing the dispensed material to adhere to (or otherwise bond with) anchor point 20. Head 16 may then be moved away from anchor point 20, and the relative movement may pull the reinforcement material from head 16. Note that movement of the reinforcement material through head 16 may be assisted (e.g., by one or more internal feed mechanisms) if desired. However, the rate at which reinforcement material is dispensed from head 16 may be primarily the result of relative movement between head 16 and anchor point 20, such that tension is created in the reinforcement material. It is contemplated that instead of or in addition to the head 16 moving away from the anchor point 20, the anchor point 20 may move away from the head 16.

[0192] A controller 26 may be provided and communicatively coupled to the support 14, the head 16, and any number of cure enhancer(s) 18. Each controller 26 may implement a single processor or multiple processors specially programmed or configured to control the operation of the system 10. The controller 26 may include one or more general-purpose or special-purpose processors or microprocessors. The controller 26 may further include or be associated with memory for storing data such as, for example, design limits, performance characteristics, operating instructions, tool paths, and corresponding parameters of each component of the system 10. Various other known circuits may be associated with the controller 26, such as power supply circuitry, signal conditioning circuitry, solenoid driver circuitry, communication circuitry, and other suitable circuitry. Additionally, the controller 26 may be capable of communicating with other components of the system 10 via wired and / or wireless transmission.

[0193] One or more maps may be stored in the memory of the controller 26 and used by the controller 26 during fabrication of the structure 12. Each of these maps may include a collection of data in the form of a look-up table, graphs, and / or equations. In the disclosed embodiment, the controller 26 may be specially programmed to reference the maps, determine the movements of the head 16 necessary to create the desired size, shape, and / or contour of the structure 12, and responsively adjust the operation of the support 14, the cure enhancer(s) 18, and other components of the head 16.

[0194] Exemplary matrices that can be used in system 10, particularly with somewhat opaque reinforcements (eg, carbon fiber), are disclosed in FIG. 2 and Tables T-1, T-2, and T-3 below.

[0195] [Table 2]

[0196] [Table 3]

[0197] [Table 4]

[0198] The double bond conversion was followed by FTIR (Fourier Transform Infrared) spectroscopy for the bulk of two batches of V1.1. Figure 2 shows the conversion rate for the first and second batches. The test was performed at 10 mW / cm 2 The reaction was performed under 405 nm LED light for 5 minutes. There appears to be little difference in reaction rate. Note that LED light with a wavelength of 325-425 nm can be used instead. [Industrial Applicability]

[0199] The disclosed system and matrix can be used to continuously manufacture composite structures having any desired cross-sectional size, shape, length, density, and / or strength. The composite structures can include any number of different reinforcements of the same or different types, diameters, shapes, structures, and configurations, each coated with a common matrix. The operation of system 10 is described in detail below.

[0200] At the start of a manufacturing event, information regarding the desired structure 12 can be loaded into the system 10 (e.g., into a controller 26 responsible for regulating the operation of the support 14 and / or head 16). This information can be, among other things, size (e.g., diameter, wall thickness, length, etc.), shape, profile (e.g., trajectory), surface features (e.g., ridge size, location, thickness, length; flange size, location, thickness, length, etc.) and finish, connection geometries (e.g., coupler, tee, splice location and size, etc.), location-specific matrix prescriptions, location-specific reinforcement prescriptions, compression requirements, cure requirements, etc. It should be noted that this information may alternatively or additionally be loaded into the system 10 at different times and / or continuously during a manufacturing event, as desired.

[0201] Based on the component information, one or more different reinforcement materials and the disclosed matrices may be selectively loaded into the head 16. For example, the reinforcement materials may be loaded into a creel (e.g., an internal head-mounted creel and / or an external off-board creel—both not shown), which may provide the matrix to the head 16. The reinforcement material(s) may then be threaded through the head 16 prior to the start of a production event. The reinforcement materials may be wetted with the matrix inside the head 16 and dispensed (e.g., pulled and / or pushed from the head 16) in a desired manner.

[0202] The head 16 may then be moved by the support 14 under the control of the controller 26 so that the matrix-wetted reinforcement material is placed against or onto the corresponding anchor points 20. The cure enhancer(s) 18 may then be selectively activated to expose the matrix to energy, thereby causing the matrix surrounding the reinforcement material to cure and bond the reinforcement material to the anchor points 20. The head 16 may then be moved in any trajectory to draw the wetted reinforcement material from the head 16 into existing surfaces and / or free spaces to form the structure 12.

[0203] In one embodiment, a cured composite article made from the curable composition (in the absence of any reinforcement) has the following physical properties: Tg greater than 130°C Flexural modulus of 1.4GPa to 2GPa. Tensile strength of 6.8MPa to 9.6MPa; and Flexural strength of 34MPa to 69MPa.

[0204] In another embodiment, the Tg is greater than 150° C., the flexural modulus is greater than 1.7 GPa, the tensile strength is greater than 7.3 MPa, and the flexural strength is greater than 45 MPa.

[0205] Example 2. Effect of varying AMOC concentration Pinning Test: For the pinning test, fibers were wetted with resin and laid on a granite slab. Excess resin was removed with a squeegee. The fibers were cured under LEDs on a conveyor system at a specific speed. A second strand of fiber was wetted and laid on top of the first cured fiber with a consistent overlap of approximately 70 mm. The overlapped fibers were then cured under LEDs as before. A qualitative test was first performed by jerking the fibers apart to observe whether they held together or how hard they had to be pulled apart. For a more quantitative test, the overlapped fibers were pulled with a known force at a constant speed (150 mm / min) in a materials testing machine.

[0206] Curing Conditions: Using LEDs provided by CC3D, a rig was constructed in which fibers resting on a granite slab could be moved under the LEDs at a controlled speed by a conveyor system. Due to the small spot size, it was not possible to measure intensity. The "good" and "very good" indicators qualitatively measured how well the cured strands stayed together in a pinning test. "Good" meant the strands could be separated by hand, but required force; "very good" meant they separated after several pulls or did not separate.

[0207] Table 4 identifies the two formulations used in the pinning tests in Table 5. Table 6 provides a general description of the formulations. Additionally, Table 7 shows that 40 wt% ACMO gives good results.

[0208] Formulations with 30% and 40% by weight ACMO both showed good results.

[0209] [Table 5]

[0210] [Table 6]

[0211] [Table 7]

[0212] [Table 8]

[0213] Example 3. Exemplary curable compositions with Tg > 200°C 50% ACMO 35% SR833S (tricyclodecane dimethanol diacrylate) 15% SR368 (Isocyanurate Triacrylate) 0.5% Omnirad 819 (bisacylphosphine oxide (BAPO))

[0214] The composition exhibited low warpage (visually) and stability for over three months at 25°C. For warpage evaluation, 15-20 layers were stacked and cured at a time using a conveyor. The parts were approximately 12 inches (30.48 cm) long. After removal from the granite slab, the parts were allowed to warp. When one end was pressed down, the other lifted up. This lifting measure was compared for various formulations.

[0215] Example 4. Application of the three-component analysis to various acrylates / acrylamides Various (meth)acrylates and (meth)acrylamides were tested for inclusion in the curable compositions of the present invention based on the results of the triple requirement analysis. Only compounds that exhibited a triple plus (+++) were considered for use as fast monomers, i.e., monomers exhibiting fast cure times.

[0216] [Table 9]

[0217] [Table 10]

[0218] [Table 11]

[0219] [Table 12]

[0220] [Table 13]

[0221] Example 5 The entries in Table 9 represent exemplary curable compositions contemplated as suitable for use with the invention described in this disclosure. The weight percent shown for each component (1, 2, 3, and 4) of Compositions A-K represents the amount of that component in a particular embodiment of that particular composition and is not intended to exclude other weight percents that may be suitable for other embodiments.

[0222] [Table 14] Some of the embodiments of the invention related to the present invention are shown below. [Embodiment 1] An actinic radiation curable composition comprising: (a) 20 to 80% by mass of at least one monomer of the following formula (I): [ka] (b) 10 to 60% by mass of at least one monomer of the following formula (II): [ka] (c) 0 to 30% by weight of one or more urethane (meth)acrylate oligomers; and (d) 0.1 to 5% by mass of one or more photopolymerization initiators; where: R 1 is H or C 1 -C 3 is alkyl; R 2 and R 3 is H, C 1 -C 3 Alkyl, CH 2 -CH(OH)C 1 -C 3 Alkyl and (CH 2 ) m X, each independently selected from the group consisting of Alternatively, R 2 and R 3 form together with the nitrogen atom to which they are attached a 3- to 6-membered saturated heterocyclic ring; X is OR 4 , S.R. 4 , N.R. 5 R 6 , OP(=O)(OR 4 ) 2 , C.H. 2 P(=O)(OR 4 ) 2 or an aromatic group; Each R 4 is H and C 1 -C 4 independently selected from the group consisting of alkyl; R 5 and R 6 is H and C 1 -C 3 are each independently selected from the group consisting of alkyl; m is 1, 2, 3, 4 or 5; R 7 、R 8 and R 9 are each independently -(CH 2 ) n O(C=O)-CR 10 =CH 2 or H, where: R 7 、R 8 and R 9 At least two of the -(CH 2 ) n O(C=O)-CR 10 =CH 2 and; R 10 is H and C 1 -C 3 selected from the group consisting of alkyl; n is 1, 2, 3 or 4. [Embodiment 2] For formula (I), R 1 is H and R 2 and R 3 The curable composition of claim 1 , wherein: [Embodiment 3] For formula (II), R 7 、R 8 and R 9 At least one of (CH 2 ) n O(C=O)-CR 10 =CH 2 2. The curable composition of claim 1, wherein n is 2. [Embodiment 4] For formula (II), R 7 、R 8 and R 9 At least two of the 2 ) n O(C=O)-CR 10 =CH 2 2. The curable composition of claim 1, wherein n is 2. [Embodiment 5] For formula (II), R 7 、R 8 and R 9 At least one of (CH 2 ) n O(C=O)-CR 10 =CH 2 where n is 2 and R 10 The curable composition of claim 1, wherein is H. [Embodiment 6] For formula (II), R 7 、R 8 and R 9 At least two of the 2 ) n O(C=O)-CR 10 =CH 2 where n is 2 and R 10 The curable composition of claim 1, wherein is H. [Embodiment 7] 2. The curable composition of claim 1, wherein the monomer of formula (I) is selected from the group consisting of the following monomers:

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Claims

1. An actinic radiation curable composition comprising: (a) 20 to 80% by weight of acryloylmorpholine; 【Chemical 1】 (b) 10 to 60% by weight of tris(2-hydroxyethyl)isocyanurate triacrylate; 【Chemistry 2】 (c) 0 to 30% by weight of one or more urethane (meth)acrylate oligomers; and (d) 0.1 to 5% by weight of one or more photoinitiators.

2. The curable composition of claim 1 further comprising a reinforcing material.

3. 3. The curable composition of claim 2, wherein the reinforcing material is selected from the group consisting of fiberglass, chopped carbon fiber, continuous carbon fiber, and Kevlar® fiber, and optionally one or more of nylon, polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), and polycarbonate may be present.

4. The curable composition according to any one of claims 1 to 3, further comprising a monomer of the following formula (III): 【Chemistry 3】 where: Each R １１ are independently H or C １ -C ３ is alkyl; R １２ is selected from the group consisting of: R １１ is H, a 3- to 7-membered heterocycle containing at least one of N, O, or S, and R １１ is C １ -C ３ When alkyl, a 4-7 membered heterocycle containing at least two of N, O or S; Optionally branched C ２ -C １０ An alkane chain, R １１ is H, at least one carbon atom of the alkane chain is substituted with N, O, S or P, and the alkane chain is C １ -C ３ terminated with an alkyl group and an optional branching group １ -C ３ C is an alkyl group ２ -C １０ Alkane chains; Optionally branched C ３ -C １０ An alkane chain, R １１ is C １ -C ３ When the alkane chain is an alkyl, at least two carbon atoms of the alkane chain are substituted with N, O, S, or P, and the alkane chain is C １ -C ３ terminated with an alkyl group and an optional branching group １ -C ３ C is an alkyl group ３ -C １０ alkane chains; and Optionally branched C ２ -C ２０ an alkane chain, one or more carbon atoms of which may be optionally substituted with N, O, S, or P, and the alkane chain is an acrylate group (—O—C(═O)—CH═CH ２ ) or a methacrylate group (—O—C(═O)—C(CH ３ ) = CH ２ ) and the optional branching group is C １ -C ３ C is an alkyl group ２ -C ２０ Alkane chain.

5. 1. A method for producing a three-dimensional printed carbon-bonded composite article using continuous fiber 3D printing, comprising: irradiating the actinic radiation curable composition of any one of claims 1 to 4 with light to form a cured three-dimensional printed carbon-bonded composite article; wherein the actinic radiation curable composition further comprises continuous carbon fibers.

6. A method for making a three-dimensional printed composite article, comprising: Discharging the actinic radiation curable composition of any one of claims 1 to 4 from a printhead, wherein the actinic radiation curable composition further comprises a reinforcing material; moving the print head during ejection of the actinic radiation curable composition; and irradiating the actinic radiation curable composition with light to form a cured three-dimensional printed composite article.

7. 7. The method of claim 5 or 6, wherein the composition is applied as a single deposit.

8. A printhead containing the curable composition of any one of claims 1 to 4.

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