Radiation curable composition

Abstract

A radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from the reaction of: a) at least one diisocyanate compound (A); b) at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group; c) at least one polymeric diol (DL); and d) at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol; wherein the urethane-urea oligomer (P) comprises at least two urea linkages obtained from the reaction of the at least one diisocyanate compound (A) with the at least one diamine (DM), wherein the urethane-urea oligomer (P) further comprises at least two urethane linkages obtained from the reaction of the at least one diisocyanate compound (A) with the at least one hydroxyl group of the compound (B), and wherein the ethylenically unsaturated group(s) are located in terminal positions of the urethane-urea oligomer (P).

Description

Technical Field

[0001] This invention relates to radiation-curable compositions particularly suitable for three-dimensional printing, and articles obtainable from said radiation-curable compositions. Background Technology

[0002] 3D printing technology has been widely used to produce 3D artifacts and objects from digital models. In this context, so-called "slot photopolymerization technologies" (such as DLP or SLA) have rapidly become leading technologies for high-resolution 3D printing, where slot photopolymerization uses a radiation curing process, such as ultraviolet irradiation, to cure liquid polymer resin materials layer by layer for additive manufacturing.

[0003] Materials commonly used in photopolymerization processes (often referred to as photocurable resins) have long been associated with undesirable properties such as brittleness, making them unsuitable for many applications. In reality, industries require high-performance photocurable resins that can provide both high toughness and high durability to the cured material. High toughness can typically only be achieved through a combination of high strength and high flexibility or high deformability.

[0004] Some solutions are described, for example, in WO2022 / 051521 (Liu et al.) and WO2022 / 157112 (Wu et al.). Without questioning the technical advantages of known solutions in the prior art, there is still a need for photocurable materials that at least partially overcome the aforementioned drawbacks. Invention Overview

[0006] According to one aspect, this disclosure relates to a radiation-curable composition comprising at least one urethane-urea oligomer (P) obtained by reacting a substance with:

[0007] a) At least one diisocyanate compound (A);

[0008] b) At least one compound containing at least one hydroxyl group and also containing at least one olefinic unsaturated group (B);

[0009] c) at least one polymeric diol (DL); and

[0010] d) At least one diamine (DM) having a number-average molecular weight (Mn) of less than 4000 g / mol;

[0011] The urethane-urea oligomer (P) comprises at least two urea bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one diamine (DM), the urethane-urea oligomer (P) further comprises at least two urethane bonds obtained by reacting the at least one diisocyanate compound (A) with at least one hydroxyl group of the at least one compound (B), and the at least one olefinic unsaturated group is located at the terminal position of the urethane-urea oligomer (P).

[0012] According to another aspect, this disclosure relates to a method for preparing the radiation-curable composition as described above, comprising the following steps:

[0013] a) Contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL) and at least one diamine (DM) to form a mixture material comprising at least one urethane-urea oligomer (P);

[0014] b) Optionally, apply heat to the mixture material; and

[0015] c) Optionally, mechanical mixing is applied to the mixture materials.

[0016] According to another aspect, this disclosure relates to the use of the radiation-curable composition as described above in a 3D printing process, particularly in a 3D printing process using a trench (photopolymerization) technique. Invention Details

[0018] According to a first aspect, this disclosure relates to a radiation-curable composition comprising at least one urethane-urea oligomer (P) obtained by reacting a substance with the following:

[0019] a) At least one diisocyanate compound (A);

[0020] b) At least one compound containing at least one hydroxyl group and also containing at least one olefinic unsaturated group (B);

[0021] c) at least one polymeric diol (DL); and

[0022] d) At least one diamine (DM) having a number-average molecular weight (Mn) of less than 4000 g / mol;

[0023] The urethane-urea oligomer (P) comprises at least two urea bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one diamine (DM), and the urethane-urea oligomer (P) further comprises at least two urethane bonds obtained by reacting the at least one diisocyanate compound (A) with at least one hydroxyl group of the at least one compound (B), and wherein the olefinic unsaturated group of the at least one compound (B) is located at the terminal position of the urethane-urea oligomer (P).

[0024] In the context of this disclosure, it has been surprisingly found that the radiation-curable compositions described above possess excellent formulation stability and advantageous formulation flexibility. Advantageously, the radiation-curable compositions of this disclosure are and remain in the form of a homogeneous (single-phase) liquid formulation when stored at room temperature for extended periods. Furthermore, the radiation-curable compositions described herein possess excellent thermal stability characteristics, making them suitable for a wide range of industrial manufacturing processes.

[0025] The urethane-urea oligomers (P) used in the radiation-curable compositions of this disclosure can be conveniently obtained using a one-pot synthesis strategy, which involves a continuous chemical reaction in only one reactor, thereby avoiding the lengthy separation and purification of any intermediate chemical compounds and improving overall process efficiency while increasing the total chemical reaction yield. Advantageously, the urethane-urea oligomers (P) do not require any additional heat treatment (e.g., annealing or deblocking steps) at temperatures typically exceeding 100°C, which could significantly reduce overall process efficiency and reproducibility.

[0026] It was quite surprising to find that the radiation-curable compositions described above are particularly suitable for forming cured polymer materials with excellent properties and performance characteristics, especially tensile strength, elongation at break, and Young's modulus. This is a particularly surprising and counterintuitive finding, because obtaining particularly high tensile strength and high elongation at break is, to some extent, technically contradictory, or at least technically difficult to achieve.

[0027] Unbound by theory, these superior properties and characteristics are believed to be primarily attributed to at least two urea bonds in the urethane-urea oligomer (P), formed by the reaction of at least one diisocyanate compound (A) with at least one diamine (DM) having a number-average molecular weight (Mn) of less than 4000 g / mol, and at least two urethane bonds formed by the reaction of at least one diisocyanate compound (A) with at least one hydroxyl group of at least one compound (B), wherein the olefinically unsaturated group is located at the terminal position of the urethane-urea oligomer (P). More specifically, the urea bonds present in the urethane-urea oligomer (P) are believed to facilitate the formation of hard segments within the cured polymer material through (particularly) strong hydrogen bonding provided by these urea bonds. The presence of these hard segments, in turn, is thought to beneficially improve the overall toughness properties of the resulting cured polymer material.

[0028] In the context of this disclosure, cured polymer materials produced from polyurethane-based photocurable resins (i.e., primarily containing conventional urethane bonds without any urea bonds) have been observed to exhibit suboptimal structural properties, which typically lead to undesirable properties such as brittleness and render them unsuitable for certain applications. Still not bound by theory, it is believed that the presence of urea bonds (particularly when located in the backbone of urethane-urea oligomers (P)) provides more optimized structural properties to the resulting cured polymer materials.

[0029] Therefore, the radiation-curable compositions disclosed herein are particularly suitable for use in 3D printing processes, especially in 3D printing using trench (light) polymerization technology.

[0030] It has been further discovered that the radiation-curable compositions described above offer excellent print quality when used in 3D printing, and generally exhibit a greater improvement in print quality compared to the use of polyurethane-based photocurable resins. Without being bound by theory, these superior printing properties are believed to be attributed again to the presence of urea bonds in the urethane-urea oligomers (P), which advantageously influence the adhesion between successive layers formed during the layer-by-layer curing steps used in the 3D printing process. This enhanced layer adhesion is believed to be facilitated by the strong hydrogen bonding provided by these urea bonds.

[0031] In a typical aspect of the urethane-urea oligomer (P) used in the radiation-curable compositions described herein, an olefinic unsaturated group derived from a compound (B) is located at each end position of the urethane-urea oligomer (P).

[0032] In one particular aspect of the radiation-curable composition described herein, the at least two urea bonds (each) of the at least one urethane-urea oligomer (P) used herein are separated from the at least one (terminal) olefinic unsaturated group by at least one urethane bond.

[0033] In another particular aspect, the at least two urea bonds (each) of the at least one urethane-urea oligomer (P) are separated from the at least one (terminal) olefinic unsaturated group by at least one urethane bond obtained by reacting the at least one diisocyanate compound (A) with at least one hydroxyl group of the at least one compound (B).

[0034] In yet another particular aspect, at least one of the at least two urea bonds of the at least one urethane-urea oligomer (P) is separated from the at least one (terminal) olefinic unsaturated group by the at least two urethane bonds or even at least three urethane bonds.

[0035] According to one particular aspect, the urethane-urea oligomer (P) used herein also comprises at least two additional urethane bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one polymeric diol (DL).

[0036] According to another specific aspect, at least one of the at least two urea bonds of the at least one urethane-urea oligomer (P) is (further) separated from the at least one (terminal) olefinic unsaturated group by the at least two additional urethane bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one polymeric diol (DL).

[0037] According to another typical aspect of the urethane-urea oligomer (P) used herein, the at least two urea bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one diamine (DM) are located in the main chain of the urethane-urea oligomer (P).

[0038] In the context of this disclosure, the statement “the at least two urea bonds are located in the main chain of the urethane-urea oligomer (P)” is intended to express that these at least two urea bonds are not directly connected to the first functional bonds of the at least one compound (B) containing at least one hydroxyl group and also containing at least one olefinic unsaturated group.

[0039] According to an advantageous aspect, the urethane-urea oligomer (P) used in this article is represented by the following formula (I):

[0040] Hydroxyl-functionalized compounds (B) – {diisocyanate compounds (A) – polymeric diols (DL)}m –{diisocyanate compound (A)–diamine (DM)} n –Diisocyanate compounds (A) –Hydroxy-functionalized compounds (B)

[0041] (I)

[0042] Where m and n are integers independently selected from 1-5 or even 1-3.

[0043] According to another advantageous aspect, the urethane-urea oligomer (P) used in this article is represented by the following formula (II):

[0044] Hydroxyl-functionalized compound (B) – Diisocyanate compound (A) – Polymeric diol (DL) – Diisocyanate compound (A) – Diamine (DM) – Diisocyanate compound (A) – Hydroxyl-functionalized compound (B)

[0045] (II)

[0046] According to yet another advantageous aspect, the urethane-urea oligomer (P) used in this article is represented by the following formula (III):

[0047] [K]-O(O)C{-N(H)-[E]-N(H)-C(O)O-[G]-O(O)C} m {-N(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)} n -N(H)-[E]-N(H)-C(O)O-[K]

[0048] (III)

[0049] Where K is a residue of compound (B), E is a residue of diisocyanate compound (A), G is a residue of polymeric diol (DL), J is a residue of diamine (DM), and m and n are integers independently selected from 1-5 or even 1-3.

[0050] According to another advantageous aspect, the urethane-urea oligomer (P) used in this article is represented by the following formula (IV):

[0051] [K]-O(O)CN(H)-[E]-N(H)-C(O)O-[G]-O(O)CN(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)-N(H)-[E]-N(H)-C(O)O-[K]

[0052] (IV)

[0053] Where K is a residue of compound (B) and E is a residue of diisocyanate compound (A).

[0054] G represents a residue of the polydiol (DL), and J represents a residue of the diamine (DM).

[0055] In one particular aspect of the radiation-curable composition described herein, the number-average molecular weight (Mn) of the at least one urethane-urea oligomer (P) is 1500-15000 g / mol, 1500-10000 g / mol, 1500-8000 g / mol, 2000-8000 g / mol, or even 2000-6000 g / mol.

[0056] The urethane-urea oligomer (P) used in the radiation-curable composition of this disclosure is obtained by reacting at least one diisocyanate compound (A) as a first component.

[0057] There are no particular limitations on the diisocyanate compound (A) used herein. Any diisocyanate compound (A) commonly known in the art may be used in the context of this disclosure. Those skilled in the art will readily identify suitable diisocyanate compounds (A) for use herein, based on the teachings of this disclosure.

[0058] According to one exemplary aspect, the diisocyanate compound (A) used herein is selected from aliphatic diisocyanates, cyclic aliphatic diisocyanates, aromatic diisocyanates, and any combination or mixture thereof.

[0059] In the context of this disclosure, it has been surprisingly found that the use of cyclic diisocyanate compounds (A) in the preparation of urethane-urea oligomers (P) advantageously affects the mechanical properties, particularly tensile strength and elongation at break, of the cured polymer material resulting from the curing of a radiation-curable composition, compared to the use of acyclic diisocyanate compounds (A). Without being bound by theory, it is believed that the use of diisocyanate compounds (A) with cyclic structures (e.g., cyclic aliphatic or aromatic diisocyanates) advantageously contributes to the formation of harder segments within the cured polymer material without sacrificing its overall flexibility.

[0060] According to an advantageous aspect, the diisocyanate compound (A) used herein is selected from 1,6-diisocyanate hexane (HDI), 1,1'-methylenebis[4-isocyanate cyclohexane] (H12MDI), 5-isocyanate-1-isocyanate methyl-1,3,3-trimethylcyclohexane (isophorone diisocyanate, IPDI), 1,4-diisocyanate benzene (BDI), 2,4-diisocyanate toluene (TDI), 1,1'-methylenebis[4-isocyanate benzene] (MDI), phenylenediamine diisocyanate (XDI), tetramethylphenylenediamine diisocyanate (TMXDI), 1,5-naphthalene diisocyanate (NDI), benzyltoluidine diisocyanate (TODI), p-phenylene diisocyanate (PPDI), and any mixture thereof.

[0061] According to a more favorable aspect, the diisocyanate compound (A) is selected from isophorone diisocyanate (IPDI), tetramethylphenyl dimethylene diisocyanate (TMXDI), 1,1'-methylenebis[4-isocyanate cyclohexane] (H12MDI), and any mixture thereof.

[0062] According to a particularly advantageous aspect, the diisocyanate compound (A) is tetramethylphenyldimethyl diisocyanate (TMXDI). It has been surprisingly found that using tetramethylphenyldimethyl diisocyanate as the diisocyanate compound (A) provides the resulting radiation-curable compositions with excellent long-term storage stability and superior thermal stability characteristics.

[0063] The urethane-urea oligomer (P) used in the radiation-curable compositions of this disclosure is obtained by further reaction with at least one compound (B) containing at least one hydroxyl group and also containing at least one olefinic unsaturated group.

[0064] There are no particular limitations on the compounds (B) used herein, as long as they contain at least one hydroxyl group and at least one olefinically unsaturated group. Those skilled in the art, guided by this disclosure, will readily identify suitable diisocyanate compounds (B) for use herein.

[0065] In one exemplary aspect of this disclosure, at least one olefinic unsaturated group of compound (B) is selected from (meth)acryloyl, (meth)acrylamide, vinyl, vinyl ether, allyl, styryl, methylstyryl, maleyl, fumary functional groups, and any combination or mixture thereof.

[0066] In one advantageous aspect, at least one olefinic unsaturated group of compound (B) is selected from (meth)acryloyl. According to this advantageous aspect, compound (B) used herein is a hydroxyl-functional (meth)acrylic acid compound.

[0067] On another advantageous aspect, compound (B) contains (essentially) a hydroxyl group.

[0068] According to one particular aspect, the compound (B) used herein is selected from a (partially) esterified product obtained by reacting at least one olefinic unsaturated carboxylic acid with at least one aliphatic and / or aromatic polyol, wherein the (partially) esterified product has a residual average hydroxyl functionality of about 1.

[0069] According to another particular aspect, the compound (B) used herein is selected from a (partially) esterified product obtained by reacting at least one aliphatic and / or aromatic polyol with (meth)acrylic acid, wherein the (partially) esterified product has a residual average hydroxyl functionality of about 1.

[0070] According to an advantageous aspect of this disclosure, the at least one compound (B) is selected from hydroxyalkyl (meth)acrylates having 1-20, 1-15, 1-10 or even 1-5 carbon atoms in an alkyl group.

[0071] According to a more favorable aspect, compound (B) is selected from hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, and any mixture thereof.

[0072] According to a particularly advantageous aspect of this disclosure, the compound (B) used in this disclosure is selected from 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and any mixture thereof.

[0073] In a typical aspect of this disclosure, at least one compound (B) used herein may be referred to as a reactive capping agent.

[0074] The urethane-urea oligomer (P) used in the radiation-curable compositions of this disclosure is obtained by further reaction using at least one polymeric diol (DL).

[0075] There are no particular limitations on the polymeric diol (DL) used herein. Any polymeric diol (DL) commonly known in the art may be used in the context of this disclosure. Those skilled in the art will readily determine suitable polymeric diols (DLs) for use herein, based on the teachings of this disclosure.

[0076] In one exemplary aspect of this disclosure, the polymeric diol (DL) used herein is selected from polyether diols, polyester diols (particularly polycaprolactone diol), polycarbonate diols, (hydrogenated) polybutadiene diols, polyacrylate diols, polyacrylate diols, and any combination or mixture thereof.

[0077] In an advantageous aspect, the at least one polymeric diol (DL) is selected from polyether diols, particularly from poly(tetramethylene ether) diol (PTMG), poly(trimethylene ether) diol (PO3G), polypropylene glycol (PPG), and any combination thereof.

[0078] In a more advantageous aspect, the at least one polymeric diol (DL) is selected from poly(tetramethylene ether) diol (PTMG), poly(trimethylene ether) diol (PO3G), and any combination thereof.

[0079] In another advantageous aspect of this disclosure, the number average molecular weight (Mn) of the at least one polymeric diol (DL) is 200-10000 g / mol, 250-8000 g / mol, 500-6000 g / mol, 500-5000 g / mol, 500-4000 g / mol, 500-3000 g / mol, 1000-3000 g / mol, or even 1500-2500 g / mol.

[0080] The urethane-urea oligomer (P) used in the radiation-curable compositions of this disclosure is obtained by further reaction with at least one diamine (DM) having a number-average molecular weight (Mn) of less than 4000 g / mol.

[0081] There are no particular limitations on the diamine (DM) used herein, provided that its number-average molecular weight (Mn) is less than 4000 g / mol. In the context of this disclosure, any diamine (DM) generally known in the art and having a number-average molecular weight (Mn) of less than 4000 g / mol may be used. Those skilled in the art will readily determine suitable diamines (DM) for use herein based on the teachings of this disclosure.

[0082] In the context of this disclosure, it has been surprisingly found that a radiation-curable composition comprising at least one urethane-urea oligomer (P) obtained by reaction using at least one diamine (DM) with a number-average molecular weight (Mn) of less than 4000 g / mol is particularly advantageous for forming cured polymeric materials with excellent properties and performance attributes in terms of mechanical properties, particularly tensile strength and Young's modulus.

[0083] According to an advantageous aspect, the number-average molecular weight (Mn) of at least one diamine (DM) used herein is less than 3000 g / mol, less than 2500 g / mol, less than 2000 g / mol, less than 1000 g / mol, less than 500 g / mol, less than 400 g / mol, less than 300 g / mol, less than 250 g / mol, less than 200 g / mol, or even less than 150 g / mol.

[0084] According to a more favorable aspect, the number-average molecular weight (Mn) of at least one diamine (DM) used herein is 100-3800 g / mol, 100-3500 g / mol, 100-3000 g / mol, 100-2500 g / mol, 100-2000 g / mol, 100-1500 g / mol, 100-1000 g / mol, 100-800 g / mol, 100-600 g / mol, 100-500 g / mol, 100-400 g / mol, 100-300 g / mol, 100-250 g / mol, or even 100-200 g / mol.

[0085] According to one exemplary aspect, at least one diamine (DM) used herein is selected from aliphatic diamines, cyclic aliphatic diamines, aromatic diamines, polyether diamines, and any combination or mixture thereof.

[0086] In the context of this disclosure, it has been surprisingly found that the use of (bi)cyclic diamines (DM) in the preparation of urethane-urea oligomers (P) advantageously influences the mechanical properties, particularly tensile strength and elongation at break, of the cured polymeric material resulting from the curing of a radiation-curable composition, compared to the use of acyclic diamines (DM). Without being bound by theory, it is believed that the use of diamines (DM) having a (bi)cyclic structure (e.g., cycloaliphatic diamines) advantageously contributes to the formation of harder segments within the cured polymeric material without sacrificing its overall flexibility.

[0087] According to an advantageous aspect, at least one diamine (DM) used herein is selected from cyclic aliphatic diamines, particularly from bicyclic aliphatic diamines, and even more particularly from 4,4′-methylenebis(cyclohexylamine), 4,4-trimethylenedipiperidine, 1,3-bis(aminomethyl)cyclohexane, and any mixture thereof.

[0088] According to a particularly advantageous aspect, at least one diamine (DM) used in this disclosure is 4,4′-methylenebis(cyclohexylamine).

[0089] In another advantageous aspect of this disclosure, the at least one diamine (DM) is selected from non-polymeric diamines.

[0090] In another advantageous alternative aspect of this disclosure, the at least one diamine (DM) is selected from polyether diamines, particularly from polyethylene glycol diamines with a number-average molecular weight (Mn) of 200-10000 g / mol.

[0091] As will be readily apparent to those skilled in the art, the molar ratio of components (A), (B), (DL), and (DM) is selected to (primarily) produce at least one urethane-urea oligomer (P) as described above. Based on the teachings of this disclosure, and without requiring any inventive skill, the selection of suitable molar ratios of components (A), (B), (DL), and (DM) for obtaining the urethane-urea oligomer (P) as described herein is entirely within the capabilities of those skilled in the art.

[0092] In one advantageous aspect of this disclosure, the molar ratios of components (A), (B), (DL) and (DM) are 1:1:1:1-5:1:1:1, 1:1:1:1-4:1:1:1, 1:1:1:1-3:1:1:1, 1.5:1:1:1-3:1:1:1, 2:1:1:1-3:1:1:1, or even 2.5:1:1:1-3:1:1:1.

[0093] Another advantage is that the molar ratio of components (A), (B), (DL) and (DM) is approximately 3:1:1:1.

[0094] According to an advantageous aspect, the double bond content (DBC) of at least one urethane-urea oligomer (P) used in this disclosure is greater than 0.45 mol / kg. As will be readily apparent to those skilled in the art, the double bond content of the urethane-urea oligomer (P) is calculated according to the following formula:

[0095] Double bond content = number of moles of acrylate groups / total mass (kg) of reactants used to prepare urethane-urea oligomer (P).

[0096] In the context of this disclosure, it has been surprisingly found that radiation-curable compositions comprising at least one urethane-urea oligomer (P) with a double bond content (DBC) greater than 0.45 mol / kg are particularly advantageous for forming cured polymeric materials with excellent properties and performance attributes in terms of mechanical properties, particularly tensile strength and Young's modulus.

[0097] According to a more advantageous aspect, the double bond content (DBC) of at least one urethane-urea oligomer (P) used in this disclosure is greater than 0.50 mol / kg, greater than 0.55 mol / kg, greater than 0.60 mol / kg, greater than 0.65 mol / kg, or even greater than 0.70 mol / kg.

[0098] In another advantageous aspect, the acquisition of at least one urethane-urea oligomer (P) used herein does not use any amino-functionalized compound with an amino functionality greater than 2 or even greater than 3. In a particularly advantageous aspect, the acquisition of at least one urethane-urea oligomer (P) used herein does not use any amino-functionalized compound with an amino functionality between 3 and 4.

[0099] In other words, and according to the aforementioned advantageous aspects, the reaction mixture for preparing at least one urethane-urea oligomer (P) is substantially free of any amino-functionalized compounds with an amino functionality greater than 2 or even greater than 3, and in particular substantially free of any amino-functionalized compounds with an amino functionality between 3 and 4.

[0100] In another advantageous aspect, the acquisition of at least one urethane-urea oligomer (P) used herein does not utilize any hydroxyl-functionalized compound with a hydroxyl functionality greater than 2 or even greater than 3. In a particularly advantageous aspect, the acquisition of at least one urethane-urea oligomer (P) used herein does not utilize any hydroxyl-functionalized compound with a hydroxyl functionality between 3 and 4.

[0101] In other words, and according to the aforementioned advantageous aspects, the reaction mixture used to prepare at least one urethane-urea oligomer (P) is substantially free of any hydroxyl-functionalized compound with a hydroxyl functionality greater than 2 or even greater than 3, and in particular substantially free of any hydroxyl-functionalized compound with a hydroxyl functionality between 3 and 4.

[0102] Unbound by theory, it is believed that using a reaction mixture of compounds for preparing at least one urethane-urea oligomer (P) and substantially free of any amino and / or hydroxyl functionalized compounds with a functionality greater than 2 will produce urethane-urea oligomers with advantageous linear (unbranched) properties, which will ultimately translate into advantageous performance properties regarding mechanical properties.

[0103] In a typical aspect, the radiation-curable compositions of this disclosure may further comprise a radiation-sensitive polymerization initiator. There are no particular limitations on suitable radiation-sensitive polymerization initiators used herein, and those skilled in the art will readily identify them upon presentation of this disclosure. Any radiation-sensitive polymerization initiator commonly known in the art may be used in the context of this disclosure.

[0104] Such an initiator may be ideal for assisting in the curing of the radiation-curable composition. Advantageously, the radiation-sensitive polymerization initiator used herein is a photoinitiator, which thus absorbs radiation (e.g., ultraviolet radiation of sufficient wavelength and intensity) to generate free radical material and initiate the curable component of the radiation-curable composition to cure.

[0105] The radiation-sensitive polymerization initiators used herein are commercially available from BASF under the trade names IRGACURE® and DAROCUR®. Specific examples of suitable radiation-sensitive polymerization initiators include 1-hydroxy-cyclohexyl-phenyl-one (available as BASF IRGACURE® IC-184). Other exemplary radiation-sensitive polymerization initiators used herein are broadly described, for example, in US2018 / 0100073-A1 (Chopra et al.).

[0106] The radiation-sensitive polymerization initiator may be present in any suitable or desired amount. In a typical aspect of this disclosure, the total amount of radiation-sensitive polymerization initiator contained in the radiation-curable composition is 0.5-15 wt%, 1-10 wt%, or even 1-5 wt%, based on the total weight of the radiation-curable composition.

[0107] In accordance with the conventions of the art, the radiation-curable compositions disclosed herein may further comprise additional radiation-polymerizable compounds to adjust certain properties or performance attributes and meet the requirements of specific target applications.

[0108] According to one particular aspect, the radiation-curable composition further comprises at least one reactive diluent (T). There are no particular limitations on suitable reactive diluents (T) used herein, and those skilled in the art will readily determine them based on the teachings of this disclosure.

[0109] The reactive diluent (T) used herein is typically selected from monofunctional (meth)acrylate monomers, difunctional (meth)acrylate monomers, trifunctional (meth)acrylate monomers, tetrafunctional (meth)acrylate monomers, pentafunctional (meth)acrylate monomers, and any mixtures thereof. Exemplary reactive diluents (T) used herein are described, for example, in US2018 / 0100073-A1 (Chopra et al.). In the context of this disclosure, the reactive diluent (T) may also be referred to as a radiation-polymerizable monomer.

[0110] According to an advantageous aspect, when determined by dynamic mechanical analysis (DMA), the glass transition temperature of at least one reactive diluent (T) used herein is greater than 70°C, greater than 80°C, greater than 90°C, greater than 100°C, greater than 110°C, greater than 120°C, or even greater than 130°C.

[0111] In the context of this disclosure, it has been surprisingly found that the use of a reactive diluent (T) with a glass transition temperature greater than 70°C in the preparation of urethane-urea oligomers (P) advantageously affects the mechanical properties, particularly tensile strength and Young's modulus, of the cured polymer material produced by curing a radiation-curable composition.

[0112] In an advantageous aspect, at least one reactive diluent (T) used herein comprises an N-vinylamide moiety. In the context of this disclosure, it has actually been surprisingly found that the use of a reactive diluent (T) comprising an N-vinylamide moiety not only advantageously affects the mechanical properties of the resulting cured polymeric material, but also provides excellent solubility characteristics for radiation-curable compositions. Still not bound by theory, it is further confirmed that these excellent solubility characteristics are facilitated by the relatively high polarity, high diluting capacity, and excellent ability to reduce viscosity buildup attributed to the N-vinylamide moiety present in the reactive diluent (T).

[0113] In a more advantageous aspect, at least one reactive diluent (T) used herein has the following general formula (V):

[0114] (L)CON(CH=CH2)(Q) (V)

[0115] Wherein L is a straight-chain, branched, or cyclic hydrocarbon group, optionally substituted with an alkyl, hydroxy, or alkoxy group and / or interrupted by an oxygen or nitrogen atom; Q is a straight-chain, branched, or cyclic hydrocarbon group, optionally substituted with an alkyl, hydroxy, or alkoxy group and / or interrupted by an oxygen or nitrogen atom; and optionally, L and Q can be covalently linked to form a linking bond or a cyclic structure.

[0116] In an even more advantageous aspect, at least one reactive diluent (T) used herein has the following general formula (VI):

[0117] (VI)

[0118] Where X is an oxygen or carbon atom, R is an alkyl, hydroxyl or alkoxy group, and n is an integer from 0 to 6, 0 to 5, 0 to 4, 0 to 3 or even 0 to 2.

[0119] In yet another more advantageous aspect of this disclosure, the at least one reactive diluent (T) is selected from N-vinylpyrrolidone, N-vinylcaprolactam, N-vinyl-5-methyloxazolidinone, N-vinylformamide, and any mixture thereof.

[0120] In a particularly advantageous aspect of this disclosure, the at least one reactive diluent (T) is selected from N-vinyl-5-methyloxazolidinone, N-vinylcaprolactam, and any mixture thereof.

[0121] In one advantageous aspect, the radiation-curable composition of this disclosure comprises 20-80 wt%, 30-80 wt%, 40-80 wt%, 40-75 wt%, 45-75 wt%, 50-75 wt%, 50-70 wt%, 55-70 wt%, or even 55-65 wt% of the (at least one) urethane-urea oligomer (P) based on the total weight of the radiation-curable composition.

[0122] In another advantageous aspect of this disclosure, the radiation-curable composition described herein comprises 20-60 wt%, 30-60 wt%, 30-55 wt%, 35-55 wt%, 35-50 wt%, or even 35-45 wt% of the (at least one) reactive diluent (T) based on the total weight of the radiation-curable composition.

[0123] According to yet another advantageous aspect, the radiation-curable composition disclosed herein comprises:

[0124] a) 20-80 wt%, 30-80 wt%, 40-80 wt%, 40-75 wt%, 45-75 wt%, 50-75 wt%, 50-70 wt%, 55-70 wt%, or even 55-65 wt% of the (at least one) urethane-urea oligomer (P);

[0125] b) 20-60 wt%, 30-60 wt%, 30-55 wt%, 35-55 wt%, 35-50 wt%, or even 35-45 wt% of the at least one of the reactive diluents (T); and

[0126] c) Optional 0-5wt%, 0.5-5wt%, or even 1-5wt% of radiation-sensitive polymerization initiator;

[0127] The wt% is based on the total weight of the radiation-curable composition.

[0128] According to one particular aspect, the radiation-curable compositions disclosed herein also contain additional oligomers, including but not limited to epoxy acrylate oligomers, polyester acrylate oligomers, urethane acrylate oligomers, amino acrylate oligomers, and any combination or mixture thereof.

[0129] In accordance with the conventions of the art, the radiation-curable compositions disclosed herein may further comprise additional compounds as optional additives. These include, but are not limited to, chain extenders, antioxidants, crosslinking agents, dyes, fillers, modifiers, stabilizers, inhibitors, adhesion promoters, and any combination or mixture thereof.

[0130] In a typical aspect, the radiation-curable compositions described herein are (substantially) non-aqueous.

[0131] In another typical aspect of this disclosure, the radiation-curable composition is (substantially) 100% solids.

[0132] The radiation-curable compositions disclosed herein have advantageous viscosity properties, making them particularly suitable for 3D printing processes, especially in 3D printing processes using trench (photopolymerization) technology.

[0133] In a typical aspect, when measured at 60°C according to the test methods described in the experimental section, the viscosity of the radiation-curable composition described herein is not greater than 5000 mPa. s, not greater than 4500 mPa s, not greater than 4000 mPa s, not greater than 3500 mPa s, not greater than 3000 mPa s, not greater than 2500 mPa s, not greater than 2000 mPa s, not greater than 1800 mPa s, not greater than 1600 mPa s, not greater than 1500 mPa s, not greater than 1400 mPa s, not greater than 1300 mPa s or even no greater than 1200 mPa s.

[0134] In another typical aspect, when measured at 60°C according to the test methods described in the experimental section, the viscosity of the radiation-curable composition described herein is 500-5000 mPa. s, 500-4000 mPa s, 1000-4000 mPa s, 1000-3500 mPa s, 1000-3000 mPa s, 1000-2500 mPa s, 1000-2000 mPa s, 1000-1800 mPa s, 1000-1600 mPa s or even 1000-1400 mPa s.

[0135] In another typical aspect, when measured at 25°C according to the test methods described in the experimental section, the viscosity of the radiation-curable composition described herein is not greater than 20,000 mPa. s, not greater than 15000 mPa s, not greater than 10000mPa s, not greater than 8000 mPa s, not greater than 7000 mPa s, not greater than 6000 mPa s, not greater than 5000 mPa s, not greater than 4000 mPa s, not greater than 3000 mPa s or even no greater than 2500 mPa s.

[0136] In another typical aspect, when measured at 25°C according to the test methods described in the experimental section, the viscosity of the radiation-curable composition described herein is 500-20000 mPa. s, 500-15000 mPa s, 500-15000 mPa s, 1000-15000 mPa s, 1000-10000 mPa s, 1500-8000 mPa s, 1500-6000 mPa s, 1500-5000mPa s, 1500-4000 mPa s, 2000-4000 mPa s or even 2000-3000 mPa s.

[0137] As previously stated, the radiation-curable compositions disclosed herein are particularly suitable for a wide range of technical applications.

[0138] On one hand, the radiation-curable compositions disclosed herein are suitable for use in 3D printing processes, particularly 3D printing processes using trench (light) polymerization technology, and even more particularly 3D printing processes using digital light processing (DLP) technology.

[0139] In another advantageous aspect, the radiation-curable compositions disclosed herein are used in coating processes.

[0140] Another advantage is that the radiation-curable compositions disclosed herein can be used in bonding or sealing processes.

[0141] In another advantageous aspect, the radiation-curable compositions described herein are used to manufacture adhesive or sealant compositions.

[0142] The radiation-curable compositions disclosed herein can be readily obtained using manufacturing techniques and processes well known to those skilled in the art. There are no particular limitations on suitable techniques and processes for obtaining the radiation-curable compositions, and those skilled in the art will readily determine them based on the teachings of this disclosure.

[0143] According to another aspect, this disclosure relates to the carbamate-urea oligomer (P) as described above.

[0144] All the specific and advantageous aspects described above regarding the radiation-curable compositions (in particular the diisocyanate compound (A), compound (B), polymeric diol (DL), and diamine (DM)) are fully applicable to the urethane-urea oligomers (P) of this disclosure.

[0145] According to another aspect, this disclosure relates to a method for preparing the radiation-curable composition as described above, comprising the following steps:

[0146] a) Contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL) and at least one diamine (DM) to form a mixture material comprising at least one urethane-urea oligomer (P);

[0147] b) Optionally, apply heat to the mixture material; and

[0148] c) Optionally, mechanical mixing is applied to the mixture materials.

[0149] In a typical aspect of the method for preparing the radiation-curable composition, the molar ratio of components (A), (B), (DL), and (DM) is selected to produce at least one urethane-urea oligomer (P) as described above.

[0150] In one particular aspect, the step of contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL), and at least one diamine (DM) is carried out by first adding the diisocyanate compound (A), then the compound (B), then the polymeric diol (DL), and then the diamine (DM) sequentially into a suitable reactor.

[0151] In one advantageous aspect, heat is applied to a mixture material comprising a urethane-urea oligomer (P) formed by contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL), and at least one diamine (DM). This is particularly advantageous for improving the solubility and reactivity properties of the various reactants. Typically, the mixture material is heat-treated at temperatures of 50-100°C, 55-95°C, or even 60-90°C.

[0152] Another beneficial aspect is the application of mechanical mixing to the mixture materials. This is also advantageous for improving the solubility and reactivity properties of the various reactants.

[0153] According to a typical aspect, the method of this disclosure further includes the step of introducing a radiation-sensitive polymerization initiator into the mixed material.

[0154] In one particular aspect, the method of this disclosure further includes the step of introducing at least one reactive diluent (T) as described above into the mixture material. Advantageously, the at least one reactive diluent (T) is introduced into the mixture material immediately before (immediately after) the step of incorporating at least one diamine (DM).

[0155] According to another aspect, this disclosure relates to a method for preparing the carbamate-urea oligomer (P) as described above, comprising the following steps:

[0156] a) Contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL) and at least one diamine (DM) to form a mixture material comprising at least one urethane-urea oligomer (P);

[0157] b) Optionally, apply heat to the mixture material; and

[0158] c) Optionally, mechanical mixing is applied to the mixture materials.

[0159] In a typical aspect of the method for preparing urethane-urea oligomers (P), the molar ratio of components (A), (B), (DL), and (DM) is selected to produce at least one urethane-urea oligomer (P) as described above.

[0160] All the specific and advantageous aspects described above regarding the method for preparing radiation-curable compositions (in particular the step of contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL) and at least one diamine (DM), and the optional step of applying heat and / or mechanical mixing to the mixture materials) are fully applicable to the method of this disclosure for preparing urethane-urea oligomers (P).

[0161] According to another aspect, this disclosure relates to resin compositions produced by the methods described above.

[0162] According to another aspect, this disclosure relates to a method for preparing a cured polymer material, comprising the following steps:

[0163] a) Provide a radiation-curable composition as described above; and

[0164] b) Expose the radiation-curable composition to photochemical radiation.

[0165] The photochemical radiation used for curing is preferably ultraviolet light, electron beams, X-rays, radioactive rays, or high-frequency waves. From an economic point of view, ultraviolet light with wavelengths of 180-400 nm is particularly preferred. After curing by irradiation, thermal curing can be carried out in the presence of a suitable external (thermal) crosslinking agent.

[0166] In one typical aspect, the radiation-curable composition described above is cured by ultraviolet irradiation in the presence of a photoinitiator.

[0167] In another aspect of this disclosure, a method for manufacturing a three-dimensional article is provided, comprising the following steps:

[0168] a) Provide a radiation-curable composition as described above;

[0169] b) Exposing the radiation-curable composition to photochemical radiation to form a cured cross-section; and

[0170] c) Repeat steps (a) and (b) to produce a (cured) three-dimensional article.

[0171] In one typical aspect, the method for manufacturing three-dimensional articles includes a tank (photopolymerization) process step.

[0172] In another aspect of this disclosure, a method for coating an object or substrate is provided, comprising the following steps:

[0173] a) Provide a radiation-curable composition as described above;

[0174] b) Applying the composition to at least a portion of the surface of the object or substrate; and

[0175] c) Curing the composition by exposing the coated surface to photochemical radiation (especially UV, UV-LED, or electron beam).

[0176] All the specific and advantageous aspects described above with respect to radiation-curable compositions (in particular diisocyanate compound (A), compound (B), polymeric diol (DL), diamine (DM) and optional reactive diluent (T)) are fully applicable to the various methods described above and according to this disclosure.

[0177] In another aspect of this disclosure, a cured polymer material produced by any of the foregoing methods is provided.

[0178] In an advantageous aspect, when measured according to the test methods described in the experimental section, the elongation at break of the cured polymer material is greater than 50%, greater than 80%, greater than 100%, greater than 120%, greater than 140%, greater than 160%, greater than 180%, greater than 200%, greater than 220%, greater than 250%, greater than 260%, greater than 280%, or even greater than 300%.

[0179] In another advantageous aspect, when measured according to the test methods described in the experimental section, the tensile strength value of the cured polymer material as described above is greater than 5 MPa, greater than 10 MPa, greater than 15 MPa, greater than 18 MPa, greater than 20 MPa, greater than 22 MPa, greater than 25 MPa, greater than 28 MPa, greater than 30 MPa, greater than 32 MPa, greater than 34 MPa, greater than 36 MPa, greater than 38 MPa, or even greater than 40 MPa.

[0180] In another advantageous aspect, when measured according to the test methods described in the experimental section, the Young's modulus of the cured polymer material is greater than 50 MPa, greater than 100 MPa, greater than 200 MPa, greater than 300 MPa, greater than 400 MPa, greater than 500 MPa, greater than 600 MPa, greater than 700 MPa, greater than 800 MPa, greater than 900 MPa, greater than 1000 MPa, greater than 1200 MPa, greater than 1250 MPa, or even greater than 1300 MPa.

[0181] According to an advantageous aspect, the cured polymer material as described above is selected from cured three-dimensional articles, cured coatings, cured adhesive compositions, and cured sealing compositions.

[0182] According to another aspect, this disclosure relates to the use of the radiation-curable composition or urethane-urea oligomer (P) as described above in a 3D printing process, particularly in a 3D printing process using a trench (light) polymerization technique, and even more particularly in a 3D printing process using a digital light processing (DLP) technique.

[0183] According to another aspect, this disclosure relates to the use of the radiation-curable composition or urethane-urea oligomer (P) as described above in the manufacture of coatings or in coating processes.

[0184] According to another aspect, this disclosure relates to the use of the radiation-curable composition or urethane-urea oligomer (P) as described above in the preparation of adhesive or sealant compositions or in adhesive or sealing processes.

[0185] Example

[0186] This disclosure is further illustrated by the following examples. These examples are for illustrative purposes only and are not intended to limit the scope of the appended claims.

[0187] Throughout this disclosure and the Embodiments section, the following test and determination methods are used to characterize the exemplary radiation-curable compositions and the cured polymer materials obtained therefrom.

[0188] Test methods

[0189] A) Molecular weight

[0190] The number-average molecular weight (Mn) was determined using conventional gel permeation chromatography (GPC) with EasyCal polystyrene standards from Agilent (molecular weight range: 370–110,500 g / mol). The sample was dissolved (1.0% wt / wt) in tetrahydrofuran (THF) containing 0.5% toluene as the flow rate label. Analysis was performed using a liquid chromatograph (Agilent HPLC 1100) equipped with six PLGel GPC columns of varying pore sizes (300 x 7.5 mm x 5 µm). Components were separated according to their molecular size in solution by the GPC column and detected by a refractive index detector. Data were collected and processed using Agilent's ChemStation GPC data analysis software.

[0191] B) Viscosity

[0192] Viscosities of various radiation-curable compositions were determined using a cone-plate rheometer MCR102e (Anton Paar) at 60°C according to test method ASTM D7867-13. The viscosity was measured over 20 seconds. - ¹A constant shear rate.

[0193] C) Mechanical properties

[0194] The elongation at break, tensile strength, and Young's modulus were determined according to test method ASTM D-882-18 at 23°C using a single-column universal tensile testing machine (Instron 4467 series). The specimens used for the tests were prepared according to the following steps:

[0195] A radiation-curable composition containing oligomers was mixed with 1.5 wt% of a suitable photoinitiator (PI-TPO) and thoroughly mixed at 900 rpm for 5 minutes in a FlackTek SpeedMixer®. The resulting material was applied as a 0.127 mm thick film to a frame made of PET film, and then covered on top with another PET film. The laminated PET sheet was cured by passing it through each side three times at 50 fpm using a Fusion Aetek UV Hg lamp (2 x 400 W / inch power). The laminated PET sheet was cut into strips 200 mm long and 12.7 mm wide. The top and bottom PET films were further removed to obtain a UV-cured free film for testing. The total thickness of the UV-cured free film was approximately 0.127 mm.

[0196] raw material

[0197] In the embodiments, the following raw materials and starting products are used.

[0198] Isophorone diisocyanate is commercially available from Sigma-Aldrich. It will be referred to as IPDI below.

[0199] Tetramethylphenyldimethyl diisocyanate is commercially available from Sigma-Aldrich. It will be referred to as TMXDI below.

[0200] 2-Hydroxyethyl acrylate is a compound containing hydroxyl and olefinic unsaturated groups, commercially available from Sigma-Aldrich. Hereinafter referred to as HEA.

[0201] 2-Hydroxyethyl methacrylate is a compound containing hydroxyl and olefinic unsaturated groups, commercially available from Sigma-Aldrich. Hereinafter referred to as HEMA.

[0202] Poly(tetrahydrofuran) is a polyether polymeric diol with a number-average molecular weight (Mn) of approximately 2000 g / mol, and is commercially available from Sigma-Aldrich. It will be referred to as PTMEG below.

[0203] Tricyclodecanediethanol is a non-polymerized cyclic aliphatic diol, commercially available from TCI Chemicals. It will be referred to as TCDM below.

[0204] 4,4′-Methylenebis(cyclohexylamine) is a bicyclic aliphatic diamine commercially available from Sigma-Aldrich. It will be referred to as MBCH below.

[0205] 4,4-Trimethylenedipiperidine is a bicyclic aliphatic diamine, commercially available from Sigma-Aldrich. It will be referred to as TMDP below.

[0206] 1,3-Bis(aminomethyl)cyclohexane is a monocyclic aliphatic diamine, commercially available from Sigma-Aldrich. It will be referred to as BACH below.

[0207] Jeffamine® D-4000 is a polyether diamine containing repeating oxypropylene units in its main chain, with a number average molecular weight of 4000 g / mol, and is commercially available from Huntsman. It will be referred to as D-4000 below.

[0208] N-Vinylmethyloxazolidinone is a radiation-polymerizable monomer, commercially available from BASF under the trade name VMOX®. It will be referred to as VMOX below.

[0209] N-Vinylcaprolactam is a radiation-polymerizable monomer, commercially available from Sigma-Aldrich. It will be referred to as NVCL below.

[0210] Isobornyl methacrylate is a radiation-polymerizable cyclic acrylate monomer, referred to as a reactive diluent, and is commercially available from Allnex. Hereinafter referred to as IBOMA.

[0211] Hydroxypropyl methacrylate (HPMA) is a radiation-polymerizable acrylate monomer, referred to as a reactive diluent, and is commercially available from Sigma-Aldrich.

[0212] 1,6-Hexanediol diacrylate is a radiation-polymerizable linear acrylate monomer, referred to as a reactive diluent, and is commercially available from Allnex. Hereinafter referred to as HDDA.

[0213] Ebecryl® 118 is a radiation-polymerizable aromatic monofunctional acrylate monomer, referred to as a reactive diluent, and is commercially available from Allnex. Hereinafter referred to as E-118.

[0214] Ebecryl® 4859 is a radiation-polymerizable urethane diacrylate oligomer, commercially available from Allnex. Hereinafter referred to as E-4859.

[0215] 2,4,6-Trimethylbenzoyl diphenylphosphonate is a photoinitiator, commercially available from Sigma-Aldrich. It will be referred to as PI-TPO below.

[0216] Example 1: General procedures for preparing exemplary carbamate-urea oligomers (P) (Ex.1-Ex.3) and comparative carbamate-urea oligomers (Ex.C1) using TMXDI as a diisocyanate.

[0217] Diisocyanate compound (A) and conventional additives (stabilizer and catalyst) were charged into a reactor at 23°C, and the mixture was stirred for 30 minutes. The reactor temperature was then set to 60°C, and compound (B) was added dropwise over 1 hour with stirring. After the addition of compound (B) was complete, the reaction mixture was stirred at 60°C for another 1 hour. Then, polymeric diol (DL) was added dropwise over 30 minutes with stirring. After the addition of polymeric diol (DL) was complete, the reaction mixture was heated to 90°C and stirred for another 2 hours. The reaction mixture was then cooled to 80°C by adding the reactive diluent (T) used. Then, diamine (DM) was added to the reaction mixture. After the addition of diamine (DM) was complete, the reaction mixture was heated again to 90°C and stirred for another 2 hours. The resulting urethane-urea oligomer (P) was then transferred to a separate container for storage.

[0218] Example 2: General procedures for preparing exemplary carbamate-urea oligomers (P) (Ex.4 to Ex.6) and comparative carbamate oligomers (Ex.C2 and Ex.C3) using IPDI as a diisocyanate.

[0219] Diisocyanate compound (A) and conventional additives (stabilizer and catalyst) were charged into a reactor at 23°C, and the mixture was stirred for 30 minutes. The reactor temperature was then set to 60°C, and compound (B) was added dropwise over 1 hour with stirring. After the addition of compound (B) was complete, the reaction mixture was stirred at 60°C for another 30 minutes. Then, the polymeric diol (DL) was first dissolved in any reactive diluent (T) used, and then added dropwise over 30 minutes with stirring. After the addition of polymeric diol (DL) was complete, the reaction mixture was maintained at 60°C and stirred for another 1 hour. Then, diamine (DM) was slowly added to the reaction mixture while keeping the temperature of the reaction mixture below 75°C. After the addition of diamine (DM) was complete, the reaction mixture was maintained at 60°C and stirred for another 30 minutes. The resulting urethane-urea oligomer (P) was then transferred to a separate container for storage.

[0220] In contrast, urethane oligomers (Ex.C2 and Ex.C3) are prepared in a similar manner to those described above, except that a diamine is not used. In Ex.C2, no additional diol is used, while in Ex.C3, a second non-polymerized diol is used instead of the diamine.

[0221] Example 3: Formulations of exemplary radiation-curable compositions (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3) comprising urethane-urea oligomers.

[0222] Exemplary radiation-curable compositions (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3) comprising urethane-urea oligomers were prepared according to the foregoing steps. The comparative composition (Ex.C1) comprises urethane-urea oligomers, wherein the number-average molecular weight of the diamine used is 4000 g / mol. The comparative compositions (Ex.C2 to Ex.C3) comprise urethane oligomers, but not urethane-urea oligomers. The corresponding formulations are shown in Table 1 below.

[0223] Table 1: Formulations of exemplary radiation-curable compositions (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3) containing urethane-urea oligomers.

[0224]

[0225] Example 4: Double bond content (DBC) and mechanical properties of exemplary radiation-curable compositions (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3) containing urethane-urea oligomers.

[0226] The mechanical properties of exemplary radiation-curable compositions (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3) containing urethane-urea oligomers were determined at 23°C according to the aforementioned test methods. The results, together with the double bond content (DBC) of the corresponding oligomers, are shown in Table 2 below.

[0227] Table 2: Double bond content (DBC) and mechanical properties of exemplary radiation-curable compositions containing urethane-urea oligomers (Ex.1-Ex.6) and comparative compositions (Ex.C1-Ex.C3).

[0228]

[0229] As can be seen from the results shown in Table 2, the radiation-curable compositions (Ex.1-Ex.6) of this disclosure exhibit an excellent balance of mechanical properties. In contrast, the compositions of comparative examples Ex.C1-Ex.C3 are less advantageous. In particular, the comparative compositions generally have deficiencies in tensile strength and Young's modulus. Furthermore, the compositions of comparative examples Ex.C1 and Ex.C2 are particularly disadvantageous due to their DBC values ​​not exceeding 0.45 mol / kg.

[0230] Example 5: Three-dimensional printability properties of exemplary radiation-curable compositions (Ex.1-Ex.3) containing urethane-urea oligomers

[0231] The 3D printability of exemplary radiation-curable compositions containing urethane-urea oligomers (Ex.1-Ex.3) was determined by printing spur gear and internal spur gear designs at 25°C with a layer thickness of 50 μm using an Asiga Max printer (385 nm). Other printing parameters included: 7.5 seconds (10.2 mW) irradiation of the base layer and 6 seconds (9.9 mW) irradiation of all other layers. The green parts were ultrasonically treated in an isopropanol (IPA) bath at 23°C for 5 minutes, dried in an oven at 60°C for 20 minutes, and then post-UV cured for 2 minutes on each side of the parts.

[0232] The radiation-curable compositions (Ex.1-Ex.3) of this disclosure have been found to possess excellent 3D printability. Components designed with spur gears and internal spur gears produced by 3D printing have been found to exhibit excellent resolution and surface finish characteristics. Furthermore, the 3D printed components have been found to possess excellent physical properties, including impact resistance, thermal properties (particularly heat distortion), and Shore hardness.

Claims

1. A radiation-curable composition comprising at least one urethane-urea oligomer (P) obtained by reacting a substance with: a) At least one diisocyanate compound (A); b) At least one compound containing at least one hydroxyl group and at least one olefinic unsaturated group (B); c) at least one polymeric diol (DL); and d) At least one diamine (DM) having a number-average molecular weight (Mn) of less than 4000 g / mol; The urethane-urea oligomer (P) comprises at least two urea bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one diamine (DM). The urethane-urea oligomer (P) further comprises at least two urethane bonds obtained by reacting at least one hydroxyl group of the at least one diisocyanate compound (A) with at least one hydroxyl group of the at least one compound (B), and The olefinic unsaturated group is located at the end of the urethane-urea oligomer (P).

2. The radiation-curable composition according to claim 1, wherein the number-average molecular weight (Mn) of the at least one diamine (DM) is less than 3000 g / mol, less than 2500 g / mol, less than 2000 g / mol, less than 1000 g / mol, less than 500 g / mol, less than 400 g / mol, less than 300 g / mol, less than 250 g / mol, less than 200 g / mol, or even less than 150 g / mol.

3. The radiation-curable composition according to claim 1, wherein at least two urea bonds of the at least one urethane-urea oligomer (P) are each separated from the at least one olefinic unsaturated group by at least one urethane bond obtained by reacting the at least one diisocyanate compound (A) with at least one hydroxyl group of the at least one compound (B).

4. The radiation-curable composition according to claim 1 or 2, wherein the urethane-urea oligomer (P) further comprises at least two additional urethane bonds obtained by reacting the at least one diisocyanate compound (A) with the at least one polymeric diol (DL).

5. The radiation-curable composition according to any one of claims 1-4, wherein the urethane-urea oligomer (P) is represented by the following formula (I): Compound (B) - {diisocyanate compound (A) - polymeric diol (DL)} m - {diisocyanate compound (A) - diamine (DM)} n - diisocyanate compound (A) - compound B (I) wherein m and n are integers independently selected from 1-5 or even 1-3.

6. The radiation-curable composition according to any one of claims 1-5, wherein the urethane-urea oligomer (P) is represented by the following formula (III): [K]-O(O)C{-N(H)-[E]-N(H)-C(O)O-[G]-O(O)C}m {-N(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)}n -N(H)-[E]-N(H) -C(O)O-[K] (III) wherein K is a residue of compound (B), E is a residue of diisocyanate compound (A), G is a residue of polymeric diol (DL), J is a residue of diamine (DM), and m and n are integers independently selected from 1-5 or even 1-3.

7. The radiation-curable composition according to any one of claims 1-6, wherein at least one olefinic unsaturated group of the at least one compound (B) is selected from (meth)acryloyl, (meth)acrylamido, vinyl, vinyl ether, allyl, styrene, methylstyrene, maleyl, fumaroyl functional groups, and any combination or mixture thereof.

8. The radiation-curable composition according to any one of claims 1-7, wherein the at least one polymeric diol (DL) is selected from polyether diol, polyester diol (especially polycaprolactone diol), polybutadiene diol, polycarbonate diol, polyacrylate diol, polyacrylate diol, and any combination or mixture thereof.

9. The radiation-curable composition according to any one of claims 1-8, wherein the at least one diamine (DM) is selected from aliphatic diamines, cycloaliphatic diamines, aromatic diamines, polyether diamines, and any combination or mixture thereof.

10. The radiation-curable composition according to any one of claims 1-9, comprising: a) 20-80wt%, 30-80wt%, 40-80wt%, 40-75wt%, 45-75wt%, 50-75wt%, 50-70wt%, 55-70wt%, or even 55-65wt% of the urethane-urea oligomer (P); b) 20-60wt%, 30-60wt%, 30-55wt%, 35-55wt%, 35-50wt%, or even 35-45wt% of reactive diluent (T); and c) Optional 0-5wt%, 0.5-5wt%, or even 1-5wt% of radiation-sensitive polymerization initiator; The wt% mentioned therein is based on the total weight of the radiation-curable composition.

11. A method for preparing a radiation-curable composition according to any one of claims 1-10, comprising the following steps: a) Contacting at least one diisocyanate compound (A) with at least one compound (B), at least one polymeric diol (DL) and at least one diamine (DM) to form a mixture material comprising at least one urethane-urea oligomer (P); b) Optionally, apply heat to the mixture material; and c) Optionally, mechanical mixing is applied to the mixture materials.

12. A method for preparing a cured polymer material, comprising the following steps: a) Provide a radiation-curable composition according to any one of claims 1-10; and b) Expose the radiation-curable composition to photochemical radiation.

13. A cured polymer material produced by the method of claim 12, wherein the elongation at break is greater than 50%, greater than 80%, greater than 100%, greater than 120%, greater than 140%, greater than 160%, greater than 180%, greater than 200%, greater than 220%, greater than 250%, greater than 260%, greater than 280%, or even greater than 300%, as determined by the test method described in the experimental section.

14. The cured polymer material according to claim 13, wherein the tensile strength value is greater than 5 MPa, greater than 10 MPa, greater than 15 MPa, greater than 18 MPa, greater than 20 MPa, greater than 22 MPa, greater than 25 MPa, greater than 28 MPa, greater than 30 MPa, greater than 32 MPa, greater than 34 MPa, greater than 36 MPa, greater than 38 MPa, or even greater than 40 MPa, as determined by the test method described in the experimental section.

15. Use of the radiation-curable composition according to any one of claims 1-10 in a three-dimensional printing process, particularly in a three-dimensional printing process using a trench (photopolymerization) technique.

Images