Powder materials (P) containing polyamide (PA) polymers and their use in additive manufacturing

Abstract

The present invention relates to a method for producing three-dimensional (3D) articles, parts or composites from a powder material (M) comprising a polyamide (PA) exhibiting 4,4'-diaminodicyclohexylmethane moieties, as well as to such powder material (M). The invention also relates to the 3D articles, parts or composites obtained from such a method, and to the use of the articles, parts or composites in oil and gas applications, automotive applications, electrical and electronic applications, aerospace, medical and consumer goods.

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims priority under European Patent Application No. 20306627.9, filed December 21, 2020, and the entire contents of this application are incorporated herein by reference for any purpose.

[0002] The present invention relates to a method for producing three-dimensional (3D) articles, parts, or composite materials from a powder material (M) containing a polyamide (PA) exhibiting a 4,4'-diaminodicyclohexylmethane moiety, and to such powder material (M). The present invention also relates to 3D articles, parts, or composite materials obtained by such methods, and to the use of articles, parts, or composite materials in petroleum and gas applications, automotive applications, electrical and electronic applications, aerospace, medical and consumer goods. [Background technology]

[0003] Many objects, from household items to motor parts, are manufactured from a single block of material, or they are crushed or sculpted from a larger block of material. Another approach to manufacturing objects involves depositing thin layers of material as powder, then adding another layer on top, and so on. This additive process gave rise to the name additive manufacturing (AM), more commonly known as 3D printing. The range of specially designed 3D printed products on the market is now considerable, from motor parts to dental implants. They can be manufactured using plastics in particular. Additive manufacturing is expected to disrupt established practices and overturn conventional assumptions about mass production in distant factories. Local manufacturing of small quantities, or even single items, closer to the end user will become feasible.

[0004] One of the fundamental limitations associated with known AM methods using polymer part materials in powder form is the lack of identification of materials that exhibit a suitable set of properties for printing 3D parts / objects with acceptable density and mechanical properties.

[0005] Polyamide powders are used to manufacture 3D articles. Examples include polyamide 12 (PA12), polyamide 11 (PA11), and polyamide 6 (PA6). These polyamides have the advantage of having a melting temperature (Tm) lower than 280°C, and therefore a much wider temperature range for their synthesis and processing in molten form. This firstly provides greater flexibility in synthesis and processing, but also results in printed parts with reduced coloration due to degradation. However, these polyamides have a low glass transition temperature (Tg), for example, lower than 50°C, and their mechanical properties, such as elastic modulus or strength, deteriorate significantly above this temperature, making them unsuitable for applications requiring high heat resistance. For example, PA12 has a Tg of 40°C, PA11 has a Tg of 45°C, and PA6 has a Tg of 50°C. Furthermore, these polyamides require a drying process before use.

[0006] Therefore, there is a need for polyamide powders that can be used to manufacture items by 3D printing, that can be used in applications requiring high heat resistance, such as the elastic modulus and strength at temperatures that occur conventionally, like the interior and exterior of automobiles (up to 100°C), and that have a higher Tg than commercially available polyamides so that they do not change dramatically due to the humidity present in the environment. There is also a need for polyamide powders that do not absorb as much moisture as commercially available polyamides. Furthermore, it is advantageous for such polyamide powders to maintain their low melting temperature (Tm) in order to minimize their thermal degradation during typically long printing times.

[0007] The polyamides of the present invention are based on the condensation of specific alicyclic diamines, 4,4'-diaminodicyclohexylmethane (PACM), and at least one long-chain aliphatic dicarboxylic acid. The polyamides derived from this combination of monomers exhibit a high Tg temperature and, at the same time, maintain their low Tm, which the applicant has indeed confirmed makes them suitable for use in 3D printing in applications that require high heat resistance. As described in Prince et al., Macromolecules 4(3):347-350, 1971, such alicyclic diamines exist in three different geometric arrangements, namely trans / trans, cis / cis, and cis / trans. That is, the applicant not only understands that such monomers are fundamental to preparing polyamides having the above-mentioned advantageous thermal properties (high Tg, low Tm), but also understands that only a specific molar ratio of the trans / trans isomer can actually bring about said improved thermal properties.

[0008] U.S. Patent No. 5,360,891 (Huels) relates to a colorless and transparent, amorphous-processable polyamide containing, as starting components, I. a linear aliphatic dicarboxylic acid; II.a) 35 to 60 mol% of trans, trans-bis(4-aminocyclohexyl)-methane; and II.b) 65 to 40 mol% of other aliphatic, alicyclic, aromatic aliphatic or aromatic diamines.

[0009] U.S. Patent Application Publication No. 2015 / 0099847 (Evonik) relates to a composition comprising a polyamide blend of two polyamides, one of which is a polyamide having bis(4-aminocyclohexyl)methane (PACM) and a linear dicarboxylic acid having 8 to 18 carbon atoms as copolymer units.

[0010] U.S. Patent No. 8,399,557 (Arkema) relates to a transparent blend or alloy comprising 1 to 99% by weight of a copolymer comprising two types of units: (A1) an amide unit containing at least one alicyclic unit and (A2) a flexible ether unit, wherein the alicyclic diamine can be selected from bis(3-methyl-4-aminocyclohexyl)methane (BMACM), para-aminodicyclohexylmethane (PACM), isophoronediamine (IPD), bis(4-aminocyclohexyl)methane (BACM), 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP) or 2,6-bis(aminomethyl)norbornane (BAMN).

[0011] None of these three documents describes the use of such polyamides in powder form for manufacturing 3D objects using 3D printing. SUMMARY OF THE INVENTION

[0012] Formula (I):

Chemical formula

[0013] The phrase "n varies between 7 and 30" means that n may be equal to 7 or 30, or in other words, in this disclosure, the endpoints of the range are included in the claimed range.

[0014] The powder material (M) of the present invention comprises a polymer component (P) (i.e., at least PA as described herein), and may also contain additional components, such as a flow aid / reagent (F) or additive (A).

[0015] The powder material (M) of the present invention may have a regular shape such as a spherical shape, or a composite shape. The material (M) can be obtained by crushing / milling or dissolving / precipitating a polymer component (P) in the form of pellets or coarse powder.

[0016] In this application, - Any description, even if it is described in relation to a particular embodiment, is applicable to and interchangeable with other embodiments of the present disclosure. - Where it is said that an element or component is included in and / or selected from an enumerated list of elements or components, in the relevant embodiments expressly contemplated herein, the element or component may be any one of the individual enumerated elements or components, or may be selected from any group of two or more of the expressly enumerated elements or components, and any element or component enumerated in a list of elements or components may be omitted from such list. - Any enumeration of numerical ranges by endpoints in this specification includes all numbers contained within the enumerated range, as well as the endpoints and equivalents of the ranges.

[0017] In a first aspect, the present invention relates to a method for manufacturing a three-dimensional (3D) article, part, or composite material, comprising the steps of depositing a continuous layer of powder material (M) and selectively sintering each layer before depositing subsequent layers, for example by electromagnetic radiation of the powder.

[0018] The additive manufacturing method of the present invention is preferably selected from the group consisting of selective laser sintering (SLS), high-speed sintering (HSS), high-speed laser sintering (HSLS), composite material additive manufacturing technology ("CBAM"), or multi-jet fusion (MJF).

[0019] Additive manufacturing is typically carried out using 3D printers.

[0020] SLS 3D printers are available, for example, from EOS Corporation under the trade name EOSINT(registered trademark)P, or from 3D Systems under the trade names ProX or sPro.

[0021] MJF 3D printers are available, for example, from Hewlett-Packard Company under the trademark name Multi Jet Fusion.

[0022] Furthermore, using powder material (M), fiber composite materials can also be manufactured, for example, in a CBAM process developed by Impossible Objects.

[0023] According to one embodiment, the process of printing a layer includes selective sintering of the powder material (M) by electromagnetic radiation of the powder material (M), for example, by a high-power laser source such as an electromagnetic beam source.

[0024] 3D objects / articles / parts can be constructed on a substrate, such as a horizontal substrate and / or a planar substrate. The substrate may be movable in all directions, such as horizontally or vertically. During the 3D printing process, the substrate can be lowered, for example, so that a continuous layer of unsintered polymer material is sintered on top of the previous layer of sintered polymer material.

[0025] In some embodiments, the process further includes the step of manufacturing a support structure. According to such embodiments, the 3D object is built on the support structure, and both the support structure and the 3D object are manufactured using the same AM method. The support structure can be useful in a plurality of situations. For example, especially when the 3D object is not planar, the support structure can be useful to provide sufficient support to the printed or printing 3D object to avoid distortion of the shaped 3D object. This is particularly applicable when the temperature used to maintain the printed or printing 3D object is lower than the recrystallization temperature of the polymer component, such as polyamide.

[0026] The 3D printer can include both a sintering chamber and a powder bed maintained at a predetermined specific temperature.

[0027] The powder material (M) to be printed can be preheated to a processing temperature (Tp) lower than the melting temperature (Tm). Tp can be lower than or exceed the glass transition (Tg) temperature of the powder. As an example, in some embodiments of the present invention, the powder material (M) is at a processing temperature (Tp) where Tp < Tg + 40 (where Tg is the glass transition temperature of the PA polymer), and is heated, for example, in the powder bed of a SLS printer, before sintering of a selected area of the powder layer (e.g., by electromagnetic radiation of the powder). Preheating of the powder material (M) makes it easier for the laser to raise the temperature of the selected area of the layer of unfused powder to the melting point. The laser causes fusion of the material only at the locations specified by the input. The laser energy exposure is typically selected based on the polymer in use and to avoid polymer degradation.

[0028] According to a second aspect of the present invention, the present invention relates to the powder material (M) itself. Such a powder material (M) is suitable for additive manufacturing (AM) and can be used especially for 3D printing. It can also be used in coatings or as a composite reinforcement.

[0029] The powder material (M) of the present invention comprises at least one polymer component (P), i.e., at least one PA. That is, the polymer component (P) of the powder material (M) may comprise one or more PAs as described below. This may also comprise at least one additional polymer material different from the PA polymers described herein, i.e., at least one polymer or copolymer. This additional polymer material can be selected from the group consisting of, for example, poly(arylene sulfide) (PAS) polymers, e.g., homopolymers of poly(phenylene sulfide) (PPS) polymers, poly(aryl ether sulfone) (PAES) polymers, e.g., poly(biphenyl ether sulfone) (PPSU) polymers or polysulfone (PSU) polymers, and poly(aryl ether ketone) (PAEK) polymers, e.g., poly(ether ether ketone) (PEEK) polymers. This additional polymer material may also be a polyamide (PA*) different from the PAs described herein, e.g., PA6, PA66, PA11, or PA12.

[0030] The PA described herein is given by formula (I): [ka] Repeating unit (R PA ) including, During the ceremony, n varies between 7 and 30, preferably between 11 and 18, and more preferably between 12 and 16, for example, n is equal to 14. Based on the total number of moles of the 4,4'-diaminodicyclohexylmethane portion in PA, at least 30 mol%, preferably at least 30 mol%, but less than 50 mol%, more preferably between 30 and 50 mol%, between 31 and 49 mol%, or between 32 and 48 mol%, of the 4,4'-diaminodicyclohexylmethane portion is in a trans / trans configuration.

[0031] Therefore, the polyamide (PA) of this disclosure has repeating units (R PA ) homopolyamide or repeating units (R PA ) and repeating unit (RPA ) different repeating unit (R* PA ) and may be a copolyamide (PA). More precisely, the expression "polyamide" hereby refers to homopolyamides present in the repeating unit (R PA ) and copolyamides containing the same, for example formula (II): [Chemical formula] 4,4'-diaminodicyclohexylmethane (PACM), wherein at least 30 mol% of the total number of moles of PACM in the reaction mixture is in the trans / trans configuration, repeating unit (R PA ) and formula (III): [Chemical formula] (where n varies between 7 and 30, preferably between 11 and 18, even more preferably between 12 and 16) is used to refer to a copolyamide containing a diacid. In formulas (I) and (III), n is most preferably equal to 14.

[0032] For example, the PA of the present invention may contain other repeating units (R* PA ) and may be arranged in blocks, alternately or irregularly.

[0033] According to the embodiments described herein, the PA consists of or consists essentially of the repeating unit (R PA ). The expression "consisting essentially of" means that the Pa contains the repeating unit (R PA ) and, based on the total number of moles of the repeating unit (R PA )+(R* PA ) in the PA polymer, less than 10 mol%, preferably less than 5 mol%, more preferably less than 3 mol%, even more preferably less than 1 mol% of other repeating units (R PA ) different from the repeating unit (R PA ).

[0034] Polyamide (PA) has repeating units (R* PA When it includes the repeating unit (R* PA ) are, for example, formula (IV) and / or formula (V): [ka] It can be expressed as, During the ceremony, R1 is a bond, optionally containing one or more heteroatoms (e.g., O, N, or S) and a halogen (e.g., fluorine, chlorine, bromine, or iodine), hydroxy(-OH), sulfo(-SO3M) (e.g., where M is H, Na, K, Li, Ag, Zn, Mg, or Ca), C1-C6 alkoxy, C1-C6 alkylthio, C1-C6 acyl, formyl, cyano, C6-C 15 Aryloxy and C6~C 15 C1-C11 are optionally substituted with one or more substituents selected from the group consisting of aryl atoms. 15 Alkyl and C6-C 30 Selected from the group consisting of aryls; R2 optionally contains one or more heteroatoms (e.g., O, N, or S) and can be a halogen (e.g., fluorine, chlorine, bromine, or iodine), hydroxy(-OH), sulfo(-SO3M) (e.g., where M is H, Na, K, Li, Ag, Zn, Mg, or Ca), C1-C6 alkoxy, C1-C6 alkylthio, C1-C6 acyl, formyl, cyano, or C6-C 15 Aryloxy and C6~C 15 C1-C11 are optionally substituted with one or more substituents selected from the group consisting of aryl atoms. 20 Alkyl and C6-C 30 Selected from the group consisting of aryls; and R3 optionally contains one or more heteroatoms (e.g., O, N, and S) and halogens (e.g., fluorine, chlorine, bromine, and iodine), hydroxy(-OH), sulfo(-SO3M) (e.g., where M is H, Na, K, Li, Ag, Zn, Mg, or Ca), C1-C6 alkoxy, C1-C6 alkylthio, C1-C6 acyl, formyl, cyano, C6-C 15Aryloxy and C6~C 15 Linear or branched C2-C molecules optionally substituted with one or more substituents selected from the group consisting of aryl atoms. 14 Selected from the group consisting of alkyl groups.

[0035] The polyamide (PA) of the present invention may have a number-average molecular weight Mn in the range of 5,000 g / mol to 40,000 g / mol, for example, 72,000 g / mol to 35,000 g / mol or 9,000 to 30,000 g / mol. The number-average molecular weight Mn is given by the following formula (1):

number

[0036] The concentrations of amines and acid groups can be determined by potentiometric titration. However, any suitable method can be used to determine the concentrations of terminal groups. For example, NMR can be used.

[0037] In some embodiments, PA is - Formula (II): [ka] 4,4'-diaminodicyclohexylmethane (PACM), wherein at least 30 mol% of PACM is in a trans / trans configuration based on the total number of moles of PACM in the reaction mixture, - Formula (III): [ka] The formula is a condensate of a reaction mixture containing a diacid (wherein n varies between 7 and 30, preferably between 11 and 18, and more preferably between 12 and 16, for example n is equal to 14).

[0038] In some preferred embodiments, PA is - Formula (II) for at least 5 mol%: [ka] 4,4'-diaminodicyclohexylmethane (PACM) (or at least 10 mol%, at least 15 mol%, at least 20 mol%, at least 25 mol%, at least 30 mol%, at least 35 mol%, at least 40 mol%, at least 45 mol%, at least 50 mol%, at least 55 mol%, at least 60 mol%, at least 65 mol%, at least 70 mol%, at least 75 mol%, at least 80 mol%, at least 85 mol%, at least 90 mol%, at least 95 mol%, or at least 98 mol% PACM) A reaction mixture containing at least one diamine component comprising 4,4'-diaminodicyclohexylmethane (PACM), wherein at least 30 mol% of PACM is in a trans / trans configuration based on the total number of moles of PACM in the reaction mixture, - Equation (III) for at least 5 mol%: [ka] A diacid or derivative thereof (wherein n varies between 7 and 30, preferably between 11 and 18, and more preferably between 12 and 16, for example n being equal to 14) (or at least 10 mol%, at least 15 mol%, at least 20 mol%, at least 25 mol%, at least 30 mol%, at least 35 mol%, at least 40 mol%, at least 45 mol%, at least 50 mol%, at least 55 mol%, at least 60 mol%, at least 65 mol%, at least 70 mol%, at least 75 mol%, at least 80 mol%, at least 85 mol%, at least 90 mol%, at least 95 mol%, or at least 98 mol% of HOOC-(CH2) n It is a condensate of a reaction mixture containing at least one dicarboxylic acid component containing -COOH.

[0039] The expression "its derivatives," when used in combination with the expression "dicarboxylic acid," is intended to mean any derivative that reacts under polycondensation conditions to form an amide bond. Examples of amide-forming derivatives include mono- or dialkyl esters of such carboxylic acids, such as mono- or dimethyl, ethyl, or propyl esters; their mono- or diaryl esters; their mono- or diaryl halides; their carboxylic acid anhydrides and their mono- or diamide, mono- or dicarboxylate salts.

[0040] The PACM monomer of formula (II) is such that, based on the total number of moles of PACM involved in the polycondensation reaction, at least 30 mol% of the monomers involved in the polycondensation reaction are in a trans / trans configuration. Such characteristics are fundamental for preparing PA polymers that have thermal properties suitable for additive manufacturing (3D printing), particularly hydrophobicity and having a high glass transition temperature (preferably above 90°C) and a low melting point (preferably below 255°C), which ensure good processing during printing, and the inventors understand that they are advantageously distinguishable from most commercially available polyamides, such as PA12 (Tg < 50°C), PA11 (Tg < 50°C), and PA6 (Tg < 60°C, hydrophilic). Furthermore, the PAs described herein advantageously exhibit a water absorption rate of less than 4% by weight, which contributes to maintaining a high glass transition temperature. In some embodiments, the PACM monomer of formula (II) is such that at least 30 mol% but less than 50 mol% of the monomer involved in the polycondensation reaction, for example, at least 31 mol%, at least 32 mol%, at least 33 mol%, at least 34 mol%, or at least 35 mol%, is in the trans / trans configuration, based on the total number of moles of PACM involved in the reaction. In some embodiments, the PACM monomer of formula (II) is such that up to 50 mol% of the monomer involved in the polycondensation reaction, for example, up to 49 mol%, up to 48 mol%, up to 47 mol%, up to 46 mol%, or up to 45 mol%, is in the trans / trans configuration, based on the total number of moles of PACM involved in the reaction. In some embodiments, 40 mol% ± 4 mol% of the PACM monomer of formula (II) involved in the polycondensation reaction is in the trans / trans configuration. In some other embodiments, 40 mol% ± 3 mol% of the PACM monomer of formula (II) involved in the polycondensation reaction is in the trans / trans configuration.

[0041] The diacids in formula (III) include, for example, nonadionic acid [HOOC-(CH2)7-COOH], decanediic acid [HOOC-(CH2)8-COOH], undecanediic acid [HOOC-(CH2)9-COOH], and dodecanediic acid [HOOC-(CH2) 10-COOH], tridecanediic acid [HOOC-(CH2) 11 -COOH], Tetradecane dioic acid [HOOC-(CH2) 12 -COOH], pentadecane dioic acid [HOOC-(CH2) 13 -COOH], Hexadecanedioic acid [HOOC-(CH2) 14 -COOH], heptadecanedioic acid [HOOC-(CH2)] 15 -COOH], octadecane dioic acid [HOOC-(CH2) 16 -COOH] and nonadecanedioic acid [HOOC-(CH2) 17 The diacid of formula (III) can be selected from the group consisting of [-COOH]. The diacid of formula (III) is preferably selected from the group consisting of dodecane diacid, tridecane diacid, tetradecane diacid, pentadecane diacid, hexadecanedioic acid, heptadecanedioic acid and octadecane diacid, and more preferably from the group consisting of tetradecane diacid, pentadecane diacid, hexadecanedioic acid, heptadecanedioic acid and octadecane diacid. More preferably, the diacid of formula (III) is hexadecanedioic acid.

[0042] The polyamide (PA) of the present invention contains, for example, at least 5 mol% of repeating units (R) derived from the above PACM. PA ), and at least one dicarboxylic acid HOOC-(CH2) n- COOH (wherein n varies between 7 and 30 (including 7 and 30)) may contain, for example, at least about 10 mol%, at least about 15 mol%, at least about 20 mol%, at least about 25 mol%, at least about 30 mol%, at least about 35 mol%, at least about 40 mol%, at least about 45 mol%, at least about 50 mol%, at least about 55 mol%, at least about 60 mol%, at least about 65 mol%, at least about 70 mol%, at least about 75 mol%, at least about 80 mol%, at least about 85 mol%, at least about 90 mol%, at least about 95 mol%, or at least 98 mol%.

[0043] The polyamide (PA) of this disclosure has repeating units (R PA) may be a polyamide that is essentially present in ). In such cases, the polyamide may be less than 2 mol% of repeating units (R PA ) are repeating units that are clearly different from (R PA It includes repeating units that are clearly different from ).

[0044] In some embodiments, PA is a copolyamide. In such cases, the condensation mixture is - At least one dicarboxylic acid component or derivative thereof, and at least one diamine component, - At least one aminocarboxylic acid, and / or - At least one lactam It may further include at least one additional component selected from the group consisting of the following.

[0045] According to this embodiment, the dicarboxylic acid component can be selected from a variety of aliphatic or aromatic components containing at least two acidic moieties -COOH. According to this embodiment, the diamine component can be selected from a variety of aliphatic or aromatic components containing at least two amine moieties -NH2.

[0046] For example, the dicarboxylic acid component is selected from the group consisting of adipic acid, isophthalic acid, terephthalic acid, 2,6-naphthalene, naphthalenedicarboxylic acid, 4,4'-bibenzoic acid, 5-hydroxyisophthalic acid, 5-sulfophthalic acid, and mixtures thereof, and 1,4-cyclohexanedicarboxylic acid. The diamine component is 1,4-diaminobutane, 1,5-diamonopentane, 2-methyl-1,5-diaminopentane, hexamethylenediamine, and 1,9-diamino The following are selected from the group consisting of nonane, 2-methyl-1,8-diaminooctoane (octoane), 1,10-diaminedecane, 1,12-dodecanediamine, m-xylylenediamine, p-xylylenediamine, H2N-(CH2)3-O-(CH2)2-O(CH2)3-NH2, bis(4-amino-3-methylcyclohexyl)methane (MACM), isophoronediamine (IPDA), bis(4-aminocyclohexyl)methane (MACM), and mixtures thereof. The lactam may be selected from the group consisting of caprolactam, laurolactam, and mixtures thereof. The amino acid may be selected from the group consisting of 1,11-aminoundecanoic acid and 4-aminomethylcyclohexanoic acid.

[0047] The polyamides (PAs) described herein can be prepared by any conventional method adapted to the synthesis of polyamides.

[0048] Preferably, the polyamides of the present invention are prepared by reacting monomers in the presence of less than 40% by weight of water, preferably less than 30% by weight, less than 20% by weight, or less than 10% by weight, preferably without the addition of water, by heating to a temperature of at least Tm + 10°C (where Tm is the melting temperature of the polyamide).

[0049] The polyamides (PAs) described herein can be advantageously prepared by solvent-free processes, i.e., by methods carried out as a molten material in the absence of a solvent. When condensation is solvent-free, the reaction can be carried out in an apparatus made of a material inert to the monomer. In this case, the apparatus is selected to provide sufficient contact of the monomer, and in this apparatus, removal of volatile reaction products is feasible. Suitable apparatuses include stirred reactors, extruders, and kneaders.

[0050] The powder material (M) of the present invention comprises one polymer component (P) containing at least one PA polymer as described above. The powder material (M) of the present invention may essentially exist in one or more polymers, for example, it may essentially exist in one PA polymer as described herein, or it may further include additional components, for example, flow aids / reagents (F) described below, and / or one or more additives (A). If the powder material (M) of the present invention contains additional components, they may be added to or blended with the polymer component as described herein before, during, or after the grinding process.

[0051] The PA of the present invention is advantageously semi-crystalline. Preferably, the PA has a melting point (Tm) of up to 255°C, preferably up to 250°C, more preferably up to 240°C, or up to 235°C, as determined by a second heating scan with a differential scanning calorimeter (DSC) in accordance with ISO 11357, using a heating and cooling rate of 20°C / min.

[0052] PA can have a melting point (Tm) of at least 180°C, preferably at least 190°C.

[0053] Preferably, the PA has a glass transition temperature (Tg) of at least 90°C, preferably at least 100°C, more preferably at least 110°C, as determined by a second heating scan with a differential scanning calorimeter (DSC) in accordance with ISO 11357, using a heating and cooling rate of 20°C / min.

[0054] PA can have a glass transition temperature (Tg) of up to 170°C and up to 160°C.

[0055] According to one embodiment, the water absorption rate of the PA of the present invention at saturation by immersion in water at 23°C is less than 4% by weight. According to this embodiment, the water absorption rate of the PA of the present invention at saturation by immersion in water at 23°C may be less than 3.5% by weight, less than 3.0% by weight, or less than 2.5% by weight. The water absorption rate at 23°C can be determined by preparing a test specimen in its dry state (water content less than 0.2% by weight) molded according to ISO 527, for example, and immersing it in deionized water at 23°C until it reaches a certain weight. The water absorption rate is given by the formula:

number

[0056] According to some embodiments of the present invention, the powder material (M) has a d size of less than 150 μm, as measured by laser scattering in isopropanol. 90 It has a value. According to one embodiment, the powder material (M) has a d of less than 120 μm, preferably less than 110 μm or less than 100 μm, as measured by laser scattering in isopropanol. 90 It has a value.

[0057] According to some embodiments of the present invention, the powder material (M) has a d size greater than 0.1 μm, as measured by laser scattering in isopropanol. 10 The powder material (M) has a value greater than 0.5 μm, preferably greater than 1 μm or greater than 2 μm, as measured by laser scattering in isopropanol. 10 It has a value.

[0058] In some embodiments of the present invention, the powder material (M) is contained in a d that is measured by laser scattering in isopropanol between 5 μm and 80 μm, preferably between 7 μm and 75 μm, or between 9 μm and 70 μm or between 11 μm and 65 μm. 50 It has a value. Powder materials (M) having such a particle size distribution are well suitable for selective laser sintering (SLS) and strengthening of composite materials and coatings, for example.

[0059] In some embodiments of the present invention, the powder material (M) has a d size less than 195 μm, as measured by laser scattering in isopropanol. 99 The d has a value. According to a preferred embodiment, the powder material (M) has a d of less than 190 μm, preferably less than 180 μm or less than 170 μm, as measured by laser scattering in isopropanol. 99 It has a value.

[0060] According to one embodiment, the powder material (M) of the present invention comprises, based on the total weight of the powder material (M), at least 50% by weight of polymer component (P), for example, at least 60% by weight of polymer component (P), at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 98% by weight, or at least 99% by weight of polymer component (P) as described herein.

[0061] According to one embodiment, the polymer component (P) includes, based on the total weight of the powder, at least 50% by weight of PA as specified herein, for example, at least 60% by weight of PAS as specified herein, at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 98% by weight, or at least 99% by weight of PA as specified herein.

[0062] Additional components may be added to the polymer component (P) before, during, or after the grinding process of the polymer component (P), particularly before using the powder for additive manufacturing, especially before the grinding process of the PA described herein. For example, the further component may be a fluidizer (F). This fluidizer (F) may be hydrophilic, for example. Examples of hydrophilic fluidizers are inorganic pigments selected particularly from the group consisting of silica, alumina, and titanium dioxide. Fumed silica can be mentioned. Fumed silica is commercially available under the trademark names Aerosil® (Evonik) and Cab-O-Sil® (Cabot). Fumed alumina is commercially available under the trademark name SpectraAl® (Cabot).

[0063] According to one embodiment of the present invention, the powder material (M) includes 0.01 to 10% by weight of a fluidizing agent (F) based on the total weight of the powder, for example, 0.05 to 8% by weight, 0.1 to 6% by weight, or 0.15 to 5% by weight of at least one type of fluidizing agent (F), for example, at least fumed silica or fumed alumina.

[0064] These silica or alumina particles consist of nanometer-sized primary particles (typically 5-50 nm for fumed silica or alumina). These primary particles bind together to form aggregates. In use as a fluidizing agent, silica or alumina is found in various forms (primary particles and aggregates).

[0065] Furthermore, the powder material (M) of the present invention may also include one or more additives (A), such as fillers (carbon fibers, glass fibers, crushed carbon fibers, crushed glass fibers, glass beads, glass microspheres, wollastonite, silica beads, talc, calcium carbonate, etc.), colorants, dyes, pigments, lubricants, plasticizers, flame retardants (halogen and halogen-free flame retardants, etc.), nucleating agents, heat stabilizers, light stabilizers, antioxidants, processing aids, fluxes, and electromagnetic absorbers. Specific examples of these optional additives (A) include titanium dioxide, zinc oxide, cerium oxide, silica or zinc sulfide, glass fibers, and carbon fibers.

[0066] The powder material (M) of the present invention may also include flame retardants such as halogen flame retardants and halogen-free flame retardants.

[0067] In another embodiment of the present invention, the powder material (M) comprises at least one additive (A) in an amount of 0.01 to 30% by weight, based on the total weight of the powder, for example, 0.05 to 25% by weight, 0.1 to 20% by weight, or 0.15 to 10% by weight of at least one additive (A).

[0068] According to one embodiment, the powder material (M) of the present invention is - At least 50% by weight of polymer component (P), - At least one fluidizing agent (F) in an amount of 0.01% to 10% by weight, 0.05 to 8% by weight, 0.1 to 6% by weight, or 0.15 to 5% by weight, - At least one optional additive (A), for example, an additive selected from the group consisting of fillers (carbon fiber, glass fiber, crushed carbon fiber, crushed glass fiber, glass beads, glass microspheres, wollastonite, silica beads, talc, calcium carbonate, etc.), colorants, dyes, pigments, lubricants, plasticizers, flame retardants (halogen and halogen-free flame retardants, etc.), nucleating agents, heat stabilizers, light stabilizers, antioxidants, processing aids, fusers, and electromagnetic absorbers, It includes, and the percentage is based on the total weight of the powder.

[0069] In a third aspect, the present invention aims to provide a method for producing a powder material (M) for use in a layered manufacturing method of three-dimensional parts, wherein the fine powder is - Grinding from coarse powder or granular material, - Dissolution of coarse powder or particulate matter in a solvent, and the subsequent precipitation process from the solvent. - Emulsification and selective washing of immiscible polymer blends by extrusion, - Extrusion of polymers in the form of small diameter filaments and cutting of filaments into small pieces. - Molten spraying or spray drying from a molten material obtained from a coarse powder or granular material. It is manufactured by [company name].

[0070] The powder material (M) of the present invention can be obtained by a step of grinding a polymer component (P), in particular a step of grinding the PA polymer described herein.

[0071] Furthermore, for example, the powder material (M) used in the additive manufacturing method of the present invention is Step 1') A step of grinding the polymer component (P), in particular a step of grinding the PA polymer described herein, Step 2') A step of blending the polymer component (P) from step 1') with an optional component, for example, at least one fluidizing agent (F), It can be obtained by [method].

[0072] Alternatively, for example, the powder material (M) used in the additive manufacturing method of the present invention is Step 1'') A step of blending a polymer component (P) with an optional component, for example, at least one fluidizing agent (F), Step 2'') Grinding the blend from Step 1''), particularly grinding the PAS polymer as described herein, It can be obtained by [method].

[0073] The grinding process can be carried out using a pin-type disc mill, a jet mill with a classifier / fluidized jet mill, an impact mill and classifier, a pin / pin-beater mill, or a wet grinding mill, or a combination of these devices. The temperature of the grinding process can be adjusted to facilitate grinding. The grinding process can be carried out in the presence of an additive that cools the temperature of the coarse or granular material or powder, such as dry ice or liquid nitrogen. The temperature of the coarse or granular material or powder before grinding may be below room temperature, below 0°C, below -20°C, below -50°C, or even below -100°C.

[0074] The pulverized powder material can preferably be separated or sieved in an air separator or classifier to obtain a predetermined fraction spectrum. The powder material (M) is preferably sieved before use in a printer. Sieving involves removing particles larger than 200 μm, 150 μm, 140 μm, 130 μm, 120 μm, 110 μm, or 100 μm using appropriate equipment.

[0075] Furthermore, the powder material (M) can be obtained by a process that includes dissolving PA pellets / coarse powder in a solvent such as monohydroxy alcohols (e.g., methanol, ethanol, propanol, butanol, and their stereoisomers…) and polyhydroxy compounds such as glycols, followed by precipitation controlled by temperature control or immersion in a non-solvent.

[0076] In a fourth aspect, the present invention also relates to three-dimensional (3D) articles, parts, or composite materials containing PA as described herein, obtained from the additive manufacturing method of the present invention, as well as to the use of said articles, parts, or composite materials in petroleum and gas applications, automotive applications, electrical and electronic applications, aerospace, medical and consumer goods.

[0077] For automotive applications, the articles may include trays (e.g., oil trays), panels (e.g., exterior panels including but not limited to quarter panels, trunks, and hoods; and interior panels including but not limited to door panels and dash panels), side panels, mirrors, bumpers, bars (e.g., torsion bars and sway bars), rods, suspension components (e.g., suspension rods, leaf springs, and suspension arms), and turbocharger components (e.g., housings, volutes, compressor wheels, and impellers), and pipes (e.g., for carrying fuel, coolant, air, and brake fluid). For oil and gas applications, the articles may include mining components such as downhole drilling pipes, metal protective liners and coatings, chemical injection pipes, subsea umbilicals, and hydraulic control lines. The articles may also include components for portable electronic devices.

[0078] According to one embodiment, the composite material obtained from the additive manufacturing process of the present invention is a continuous fiber-reinforced thermoplastic composite material. The fibers may consist of carbon, glass, or organic fibers such as aramid fibers.

[0079] In a fifth aspect, the present invention relates to the use of the powder material (M) described herein for the manufacture of 3D objects using additive manufacturing, preferably selective laser sintering (SLS), additive manufacturing techniques based on composite materials ("CBAM"), or multi-jet fusion (MJF).

[0080] The present invention will be described below in relation to the following embodiments, but the purpose is merely illustrative and not intended to limit the scope of the invention.

[0081] Experiment section raw materials PACM: 4,4'-methylene-bis-cyclohexylamine, commercially available from BASF under the name Dicykan, in 45-50 mol% trans / trans isomers. PACM*: 4,4'-methylene-bis-cyclohexylamine, commercially available from Evonik under the name Vestamin (registered trademark) PACM, in 17-24 mol% trans / trans isomers. C14 diacid: Tetradecane diacid, commercially available from Cathay Biotech Inc. C15 diacid: Pentadecane diacid, commercially available from Cathay Biotech Inc. C16 diacid: Hexadecanedioic acid, commercially available from Cathay Biotech Inc. C18 diacid: Octadecanedioic acid, commercially available from Elevance. PA12: Commercially available from Evonik PA6: Commercially available from Domo Chemicals

[0082] Synthesis Examples Four polyamides were synthesized by melt polycondensation of PACM with one of the C14, C15, C16, or C18 dibasic acids.

[0083] Synthesis of PACM.16 (the present invention): 95.5 g (0.45 mol) of PACM, 128.4 g (0.44 mol) of C16 diacitor, and 4.16 g of an aqueous solution of sodium hypophosphate monohydrate (5% wt, 2 mmol) were introduced into a stainless steel reactor equipped with a mechanical stirrer. The reactor was purged with nitrogen, and the temperature inside the reactor was gradually increased to 275°C. The reaction proceeded at atmospheric pressure. Condensation water and water from the catalyst solution were removed by distillation. The reaction mixture was maintained at 275°C for 30 minutes. Next, the resulting polymer was released as strands and pelletized.

[0084] Synthesis of PACM.14, PACM.15, and PACM.18 (the present invention): The same procedure used for PACM.16 was employed for the preparation of these polyamides.

[0085] Synthesis of PACM*.16 (comparative example): The same procedure as for PACM.16 was used to prepare this polyamide, except that PACM with a trans / trans isomer concentration of 17-24 mol% was used (referred to as PACM*).

[0086] Characterization of polymer components Determination of Mn by end group analysis The terminal groups of polyamides, amine terminal groups (-NH2), and carboxylic acid terminal groups (-COOH) are determined by potentiometric titration and expressed in mmol / kg. Next, the number-average molecular weight is determined by formula (1) and expressed in g / mol. The concentrations of the terminal groups and the calculated number-average molecular weights (Mn) are shown in Tables 1 and 2 below.

[0087] [Table 1]

[0088] DSC DSC analysis was performed in accordance with DSC 8000 (Perkin Elmer) ISO 11357, and data were collected using a method of two heating cycles and one cooling cycle. The protocol used was as follows: First heating cycle from 30.00°C to 300.00°C at 20.00°C / min; isothermal for 5 minutes; first cooling cycle from 300.00°C to 30.00°C at 20.00°C / min; second heating cycle from 30.00°C to 300.00°C at 20.00°C / min. Melting temperature (T m The melt crystallization temperature (T) is recorded between the first and second heating cycles. mc ) is recorded during the cooling cycle, and the glass transition temperature (T g This is recorded during the second heating cycle.

[0089] Water absorption rate Polyamide test specimens were molded according to ISO 527 in their dry state (moisture content less than 0.2% by weight), and then immersed in deionized water at 23°C until a certain weight was reached. The water absorption rate was given by the formula:

number

[0090] result

[0091] [Table 2]

[0092] As shown in Table 1, the PACM*.16 polymer obtained as a result of the condensation of PACM* with C16 diacid has no melting point or crystallinity point. It is amorphous.

[0093] All polyamides of the present invention advantageously exhibit a water absorption rate of less than 4%.

[0094] Preparation and characterization of powders PACM.16 and PACM*.16 were milled into powder using an impact mill (SPEX Certiprep 6850 freezer / mill) until they became PSD, as follows: 5 <d 50 <80 microns, ·d 90 <150 microns.

[0095] Particle size was determined for the polymer by an average of three runs using laser scattering techniques on a Malvern Mastersizer 3000 analyzer in wet mode (128 channels, 0.0215–1408 μm). The solvent used was isopropanol with a refractive index of 1.38, and it was assumed that the particles had a refractive index of 1.59. Ultrasonic mode was enabled (25 W / 60 sec), and the flow rate was set to 55%.

[0096] Next, the two powders were heated to 200°C for 15 hours under N2 conditions (i.e., 20–30°C lower than Tm, conditions typically applied to powder beds during addition by SLS).

[0097] After very long heat treatment, the PACM*.16 powder bed melts, yielding a solid block when cooled to 20°C. Conversely, PACM.16 remains powdery to the naked eye, and the powder can be easily dispersed by gentle stirring with a spatula. This demonstrates that very little particle aggregation (i.e., undesirable sintering) occurs, which is crucial for ensuring accuracy of shape during printing, easy removal of unused powder around printed parts, and the reusability of the powder.

Claims

1. A method for manufacturing three-dimensional (3D) articles, parts, or composite materials, a) Equation (I): 【Chemistry 1】 Repeating unit (R ＰＡ A polyamide (PA) polymer comprising, During the ceremony, n varies between 7 and 30. - A step of depositing a continuous layer of powder material (M) containing at least one polyamide (PA) polymer, wherein at least 30 mol% of the 4,4'-diaminodicyclohexylmethane portion in the PA is in a trans / trans configuration, based on the total number of moles of the 4,4'-diaminodicyclohexylmethane portion in the PA, b) A process of printing the layer before depositing the subsequent layer A method that includes this.

2. The method according to claim 1, wherein step b) includes selective sintering of the powder material (M) by means of electromagnetic radiation.

3. The aforementioned PA, - Formula (II): 【Chemistry 2】 4,4'-diaminodicyclohexylmethane (PACM), wherein at least 30 mol% of PACM in the reaction mixture is in a trans / trans configuration, based on the total number of moles of PACM in the reaction mixture, - Formula (III): 【Transformation 3】 The diacid or derivative thereof The method according to claim 1 or 2, wherein the product is a condensate of a reaction mixture containing (wherein n varies between 7 and 30).

4. The method according to any one of claims 1 to 3, wherein the PA is such that n varies between 11 and 18.

5. The method according to any one of claims 1 to 4, wherein the PA is such that, based on the total number of moles of the 4,4'-diaminodicyclohexylmethane portion in the PA, at least 30 mol% and less than 50 mol% of the 4,4'-diaminodicyclohexylmethane portion are in a trans / trans configuration.

6. The method according to any one of claims 1 to 5, wherein the PA has a melting point (Tm) of up to 255°C or up to 235°C when determined in a second heating scan with a differential scanning calorimeter (DSC) in accordance with ISO 11357, using a heating and cooling rate of 20°C / min.

7. The method according to any one of claims 1 to 6, wherein the PA has a glass transition temperature (Tg) of at least 90°C when determined in a second heating scan with a differential scanning calorimeter (DSC) in accordance with ISO 11357, using a heating and cooling rate of 20°C / min.

8. The method according to any one of claims 1 to 7, wherein the water absorption rate of PA at saturation by immersion in water at 23°C is less than 4% by weight.

9. Equation (I): 【Chemistry 4】 Repeating unit (R ＰＡ A polyamide (PA) polymer comprising, During the ceremony, n varies between 7 and 30. - The PA comprises at least one polyamide (PA) polymer in which at least 30 mol% of the 4,4'-diaminodicyclohexylmethane moiety is in a trans / trans configuration, based on the total number of moles of the 4,4'-diaminodicyclohexylmethane moiety in the PA, and the d range of 5 to 80 μm is measured by laser scattering in isopropanol. ５０ A powder material (M) having a value.

10. The powder material (M) according to claim 9, obtained by crushing pellets of PA or by a method including dissolving / precipitating the PA.

11. Material (M) has a d of less than 150 μm, as measured by laser scattering in isopropanol. ９０ A powder material (M) according to any one of claims 9 to 10, having a value.

12. A three-dimensional (3D) article, part, or composite material obtained by additive manufacturing from a powder material (M) according to any one of claims 9 to 11.

13. Formula (I) for manufacturing a three-dimensional (3D) object using additive manufacturing: 【Transformation 5】 Repeating unit (R ＰＡ The use of polyamide (PA) polymers containing ) During the ceremony, n varies between 7 and 30. - Use of a polyamide (PA) polymer in which at least 30 mol% of the 4,4'-diaminodicyclohexylmethane portion is in a trans / trans configuration, based on the total number of moles of the 4,4'-diaminodicyclohexylmethane portion in the PA.

14. The PA is measured by laser scattering in isopropanol and has a range of d in the range of 5 to 80 μm. ５０ The use according to claim 13, wherein the powder form has a value.

15. Use of the articles, parts, or composite materials described in claim 12 in petroleum or gas applications; automotive applications; electrical or electronic applications; or in aerospace, medical, or consumer goods.

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