Resin composition for 3D printer, and molded article and laminate of the same

Abstract

To provide a resin for a 3D printer which has small contraction in a cooling step, and has a low melting point and flexibility.SOLUTION: A resin composition for a 3D printer contains a polar group-containing polyolefin resin (P) having a structural unit (A) derived from olefin and a structural unit (B) derived from a monomer containing a polar group, containing 70 to 99.99 mol% of the structural unit (A) and 0.01 to 30 mol% of the structural unit (B) in the polar group-containing polyolefin resin, and having a melt flow rate measured under the conditions of a temperature of 190°C and a load of 2.16 kg of 0.01 to 3,000 g / 10 min, optionally, a thermoplastic resin that does not correspond to the (P), wherein the amount of the (P) is 50 mass% or more with respect to the whole resin composition.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition for 3D printers, in particular a resin composition for 3D printers that has excellent adhesion to different materials, as well as a molded article and a laminate thereof. [Background technology]

[0002] 3D printing is a technology for manufacturing three-dimensional objects based on computer-generated 3D model data. Unlike molding with a mold or cutting, 3D printing does not require molds or cutting tools, can respond immediately to frequent design changes, and can create hollow shapes and complex internal shapes. For these reasons, 3D printing technology is rapidly gaining popularity in a wide range of fields.

[0003] 3D printing techniques generally involve layering cross-sectional shapes from 3D model data to create a shape, and various layering methods are collectively referred to as additive manufacturing. Of the various layering methods, the material extrusion method is easy to use because it does not require any additional equipment. Material extrusion is a method of creating a three-dimensional shape by melting thermoplastic resin in pellet or filament form and layering it while extruding it. Plastics such as PLA and ABS resin can also be used, allowing for the creation of molded products tailored to the characteristics of each plastic. Because the operability of 3D printers varies depending on the physical properties of the resin, attempts have been made to blend various resins for use in 3D printers (Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2020-503186 [Patent Document 2] Special Publication No. 2020-500112 [Patent Document 3] Special Publication No. 7-94486 Publication [Patent Document 4] Japanese Patent Publication No. 8-25586 [Patent Document 5] Japanese Patent Application Laid-Open No. 2015-163691 Summary of the Invention [Problem to be solved by the invention]

[0005] While 3D printing technology using material extrusion has many advantages, its use can be difficult depending on the physical properties of the resin. For example, unlike modeling that involves cutting to a specific dimension, 3D printing using material extrusion involves a cooling process after the molten resin is extruded. If shrinkage occurs during cooling and dimensions change, it may not be possible to print the desired shape. For this reason, amorphous thermoplastic resins are mainly used with the molten resin extrusion method, limiting the resin options. Polyolefins in particular have the advantages of being inexpensive and having excellent mechanical properties, but as a crystalline resin, they tend to shrink and therefore have been considered unsuitable for 3D printing. Meanwhile, in order to popularize 3D printing technology, it is also necessary to consider the safety of the method itself. 3D printing requires a heating unit to melt the resin used as the material during the process, and the area around the outlet from which the molten resin is ejected must also be heated. To melt the resin, it must be heated to a temperature above its melting point, and from a safety perspective, 3D printing should be performed at the lowest possible temperature. Furthermore, by making the model itself flexible, the risk of cuts and other injuries during handling can be reduced.

[0006] Recent advances in 3D printing technology have made it possible to build not just single materials but also composites or layer various materials. However, when using multiple materials in 3D printing, the interlayer strength between the materials is weak, and the desired product cannot be obtained. One reason for this is thought to be that in the process of 3D printing, in which molten resin is layered on a metal plate called a bed, the adhesion between the metal plate and the resin is insufficient, causing the resin to shrink when cooled, resulting in the product floating off the bed. For these reasons, there is a demand for 3D printing materials that have good adhesion to different materials. Thus, there is a demand for resins used in 3D printers that have minimal shrinkage during the cooling process, a low melting point, flexibility, and adhesive properties with different materials. The present application aims to provide such a resin for 3D printers. [Means for solving the problem]

[0007] The present inventors have discovered that the above problems can be solved by using a polar group-containing polyolefin resin with specific characteristics. By adjusting the polar groups in the polar group-containing polyolefin resin, it is possible to control the crystallinity and / or bond it to different materials. Despite being primarily composed of a crystalline resin called polyolefin resin, shrinkage is less likely to occur during the cooling process after extrusion of the molten resin in 3D printing. This allows for molding at lower temperatures than the thermoplastic resins used in previous 3D printing. Furthermore, the resin possesses flexibility, giving it an advantage in terms of safety. This discovery led to the creation of the present invention.

[0008] That is, the present invention relates to the following items. [1] A polar group-containing polyolefin resin having a structural unit (A) derived from an olefin and a structural unit (B) derived from a monomer containing a polar group, wherein the polar group-containing polyolefin resin contains 70 to 99.99 mol% of the structural unit (A) and 0.01 to 30 mol% of the structural unit (B), and the melt flow rate measured under conditions of a temperature of 190°C and a load of 2.16 kg is 0.01 to 3000 g / 10 min. A resin composition for 3D printers, optionally containing a thermoplastic resin other than (P), wherein the amount of (P) is 50 mass% or more of the entire resin composition. [2] The resin composition for 3D printers according to [1], wherein the structural unit (A) is derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 12 carbon atoms. [3] The resin composition for 3D printers according to [1] or [2], wherein the structural unit (B) is derived from at least one selected from the group consisting of alkyl(meth)acrylates having an alkyl group with 1 to 8 carbon atoms, alkoxy(meth)acrylates having an alkoxyalkyl group with 2 to 8 carbon atoms, unsaturated carboxylic acids, unsaturated dicarboxylic acids, unsaturated dicarboxylic anhydrides, amino groups, silanol groups, and glycidyl groups. [4] The resin composition for a 3D printer according to any one of [1] to [3], wherein the structural unit (B) is derived from at least one selected from the group consisting of unsaturated carboxylic acids, unsaturated dicarboxylic acids, and unsaturated dicarboxylic acid anhydrides. [5] The polar group-containing polyolefin resin (P) is a polyolefin consisting of the structural unit (A) graft-modified with the structural unit (B), [1] to [4], the resin composition for a 3D printer according to any one of [1] to [4]. [6] The resin composition for 3D printers according to any one of [1] to [5], characterized in that the polar group-containing polyolefin resin (P) has a melting point of 140°C or lower. [7] The resin composition for 3D printers according to any one of [1] to [6], characterized in that the polar group-containing polyolefin resin (P) has a melting point of 30°C or higher. [8] The resin composition for 3D printers according to any one of [1] to [7], characterized in that the polar group-containing polyolefin resin (P) has a flexural modulus of 1800 MPa or less. [9] The resin composition for 3D printers according to any one of [1] to [8], characterized in that the crystallinity of the polar group-containing polyolefin resin (P) is 50% or less.

[10] A 3D printed product, characterized in that it is formed by depositing the resin composition for a 3D printer described in any one of [1] to [9] in a molten state into one or more lines.

[11] A 3D printed product comprising a deposition layer formed by depositing the resin composition for a 3D printer according to any one of [1] to [9] in a molten state in one or more lines, and an adherend layer to which the deposition layer is adhered that is not easily adhered with polyolefin.

[12] A laminate comprising at least a layer made of the resin composition for a 3D printer according to any one of [1] to [9] above, and an adherend layer.

[13] The 3D printed product described in

[11] or the laminate described in

[12] , characterized in that the adherend layer is made of at least one substrate selected from the group consisting of glass, aluminum, polyamide, and ethylene-vinyl alcohol copolymer.

[14] A method for producing a laminate, comprising the steps of: heating a resin composition for a 3D printer according to any one of [1] to [9] above using a 3D printer to melt it; depositing the melted resin composition in multiple layers to form a shaped article; cooling and solidifying the shaped article; and adhering the 3D printed article formed by these steps to an adherend layer.

[15] The resin composition for 3D printers according to any one of [1] to [9] above, wherein the resin composition is formed into a flat plate with a thickness of 0.5 mm, and the plate is laminated on a 25 mm x 100 mm aluminum plate at a heating temperature of 180°C for 10 minutes. A test piece cut to a width of 10 mm is then subjected to T-peel testing using a tensile tester. When the adhesive strength is measured, the adhesive strength is 10 N / 10 mm or more.

[16] The resin composition for a 3D printer according to any one of [1] to [9] above, wherein the resin composition is formed into a flat plate with a thickness of 0.5 mm, and is superimposed on a 25 mm × 100 mm glass, and the plates are heated at 180 ° C for 10 minutes. When a test piece with a 10 mm wide slit is peeled off at 90 ° using a tensile tester, the adhesive strength is 10 N / 10 mm or more.

[17] The resin composition for 3D printers according to any one of [1] to [9] above, wherein the resin composition is formed into a flat plate with a thickness of 0.5 mm, and is superimposed on a 25 mm × 100 mm nylon (registered trademark) film, and the resulting laminate is heated at 180°C for 10 minutes. The laminate is then sandwiched between aluminum plates and quenched for 3 minutes. A test piece is cut out to a width of 10 mm. When the test piece is subjected to T-peel testing using a tensile tester, the adhesive strength of the resin composition for 3D printers is 10 N / 10 mm or more.

[18] A resin composition for 3D printers according to any one of [1] to [9] above, wherein the resin composition is formed into a flat plate with a thickness of 0.5 mm and is superimposed on a 25 mm x 100 mm saponified ethylene-vinyl acetate copolymer resin (EVOH), and the resulting mixture is heated at 180°C for 10 minutes. The mixture is then sandwiched between aluminum plates and quenched for 3 minutes. A test piece is cut out to a width of 10 mm, and when measured by T-peel using a tensile tester, the adhesive strength of the resin composition for 3D printers is 10 N / 10 mm or more. [1-1] A resin composition for 3D printers, comprising: a polar-group-containing polyolefin resin (P) having structural units (A) derived from an olefin and structural units (B) derived from a monomer containing a polar group, wherein the polar-group-containing polyolefin resin contains 70 to 99 mol% of structural units (A) and 1 to 30 mol% of structural units (B), and wherein the polar-group-containing polyolefin resin has a melt flow rate of 0.01 to 3000 g / 10 min measured under conditions of a temperature of 190°C and a load of 2.16 kg; and optionally a thermoplastic resin other than (P), wherein the amount of (P) is 50 mass% or more of the entire resin composition. [Effects of the Invention]

[0009] According to the present invention, a resin composition for 3D printers is provided that uses a polar group-containing polyolefin resin (P) with specific characteristics, which makes it possible to reduce shrinkage of molded products during the molding process. The polar group-containing polyolefin resin (P) of the present invention is a soft olefin polymer that is more flexible than ordinary polyolefins and is characterized by a low degree of crystallinity. Compared to thermoplastic resins used in 3D printing to date, it can be molded at low temperatures and, due to its flexibility, has advantages in terms of the safety of molded products, making it suitable for a wide range of applications. Furthermore, the polar group-containing polyolefin resin (P) of the present invention has excellent adhesion to different materials due to the inclusion of polar groups. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention relates to a resin composition for 3D printers, which comprises a polar-group-containing polyolefin resin (P) having a structural unit (A) derived from an olefin and a structural unit (B) derived from a monomer containing a polar group, and optionally a thermoplastic resin other than (P), wherein the amount of (P) is 50 mass% or more of the entire resin composition, as well as a molded article and a laminate using the resin.

[0011] The resin composition of the present invention and the polar group-containing polyolefin resin (P) related thereto will be described in detail below. In this application, "(meth)acrylate" means acrylate or methacrylate. In this application, the symbol "to" indicating a numerical range is used to mean that the numerical values ​​before and after it are included as the lower and upper limits. In this application, the polar group-containing polyolefin resin (P) means a binary or higher copolymer having at least one structural unit (A) and at least one structural unit (B).

[0012] [1] Polar group-containing polyolefin resin (P) The polar group-containing polyolefin resin (P) used in the present invention has, as essential constituent units, a structural unit (A) derived from an olefin and a structural unit (B) derived from a monomer containing a polar group, and may optionally further contain an optional structural unit (C), and is characterized in that these structural units are copolymerized, preferably randomly copolymerized, or graft-modified.

[0013] (1) Structural unit (A) The structural unit (A) is a structural unit derived from an olefin. An olefin is a hydrocarbon containing at least one carbon-carbon double bond, and a specific example of the olefin from which the structural unit (A) is derived is at least one selected from the group consisting of structural units derived from ethylene and α-olefins having 3 to 20 carbon atoms. The α-olefins involved in the present invention have the structural formula: CH═CHR 18 is an α-olefin having 3 to 20 carbon atoms (R 18 is a hydrocarbon group having 1 to 18 carbon atoms, which may have a linear or branched structure. The α-olefin more preferably has 3 to 12 carbon atoms.

[0014] Specific examples of the olefin from which the structural unit (A) is derived include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 3-methyl-1-butene, and 4-methyl-1-pentene. The structural unit (A) may be derived from a petroleum raw material or a non-petroleum raw material such as a plant raw material. The structural unit (A) may be of one type or of multiple types. Examples of combinations of the two include ethylene-propylene, ethylene-1-butene, ethylene-1-hexene, ethylene-1-octene, propylene-1-butene, propylene-1-hexene, and propylene-1-octene. Examples of combinations of the three include ethylene-propylene-1-butene, ethylene-propylene-1-hexene, ethylene-propylene-1-octene, propylene-1-butene-hexene, and propylene-1-butene-1-octene.

[0015] The olefin from which the structural unit (A) of the present invention is derived preferably contains ethylene as an essential component and may further contain, as necessary, one or more α-olefins having 3 to 20 carbon atoms. The amount of ethylene in the structural unit (A) can be 50 to 100 mol %, preferably 70 to 100 mol %, and more preferably 90 to 100 mol %, based on the total amount (mol) of the structural unit (A).

[0016] (2) Structural unit (B) The structural unit (B) according to the present invention is a structural unit derived from a monomer containing a polar group. Examples of the monomer containing a polar group include (meth)acrylic acid esters, and monomers having one or more functional groups selected from the group consisting of unsaturated carboxylic acids, unsaturated dicarboxylic acids, unsaturated dicarboxylic acid anhydrides, amino groups, silane groups, glycidyl groups, and hindered amine groups. From the viewpoint of improving adhesiveness, the polar group is preferably an unsaturated carboxylic acid, unsaturated dicarboxylic acid, unsaturated dicarboxylic acid anhydrides, amino groups, silane groups, or glycidyl groups, and more preferably an unsaturated carboxylic acid, unsaturated dicarboxylic acid, unsaturated dicarboxylic acid anhydrides, or glycidyl groups.

[0017] As the (meth)acrylic acid ester, at least one of alkyl(meth)acrylates having an alkyl group containing 1 to 8 carbon atoms and alkoxy(meth)acrylates having an alkoxyalkyl group containing 2 to 8 carbon atoms is used, and these can be used alone or in combination. Here, (meth)acrylate refers to acrylate or methacrylate. Examples of alkyl(meth)acrylates that can be used include methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate, n-hexyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, and n-octyl(meth)acrylate. Generally, a longer alkyl chain length is advantageous in terms of moldability but disadvantageous in terms of heat resistance, while a shorter chain length has the opposite tendency. Therefore, methyl acrylate, ethyl acrylate, and butyl acrylate are preferred from the viewpoint of a balance between moldability and heat resistance. More preferably, methyl acrylate and ethyl acrylate are used. Furthermore, examples of the alkoxyalkyl(meth)acrylate that can be used include methoxymethyl(meth)acrylate, methoxyethyl(meth)acrylate, ethoxyethyl(meth)acrylate, n-butoxyethyl(meth)acrylate, ethoxypropyl(meth)acrylate, methoxyethoxyethyl(meth)acrylate, and ethoxyethoxyethyl(meth)acrylate.

[0018] Examples of monomers containing unsaturated carboxylic acids and / or unsaturated dicarboxylic acid anhydrides include unsaturated dicarboxylic acids or anhydrides thereof, such as maleic acid, fumaric acid, citraconic acid, itaconic acid, 2,7-octadien-1-ylsuccinic acid, and 5-norbornene-2,3-dicarboxylic acid, and unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, furoic acid, crotonic acid, vinyl acetate, and pentenoic acid. Maleic anhydride, 2,7-octadien-1-ylsuccinic anhydride, and 5-norbornene-2,3-dicarboxylic acid anhydride are more preferred, with maleic anhydride being particularly preferred. (Meth)acrylic acid units produced by deesterifying (meth)acrylic acid ester units are considered to be structural units derived from (meth)acrylic acid.

[0019] Examples of monomers containing a glycidyl group include ω-alkenyl epoxides such as 1,2-epoxy-9-decene, 4-hydroxybutyl acrylate glycidyl ether, glycidyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, 5-hexene epoxide, 6-heptene epoxide, 7-octene epoxide, 8-nonene epoxide, 9-decene epoxide, 10-undecene epoxide, and 11-dodecene epoxide, 2-methyl-6-heptene epoxide, 2-methyl-7-octene epoxide, and 2-methyl-8-nonene epoxide. ω-alkenyl epoxides with a branch in the molecular structure such as 2-methyl-9-decene epoxide and 2-methyl-10-undecene epoxide; unsaturated glycidyl ethers such as allyl glycidyl ether, 2-methylallyl glycidyl ether, glycidyl ether of o-allylphenol, glycidyl ether of m-allylphenol, and glycidyl ether of p-allylphenol; 4-hydroxybutyl (meth)acrylate, acrylic acid, methacrylic acid, glycidyl p-styrylcarboxylate, endo-cis-bicyclo[2,2,1]hept-5- Glycidyl esters of unsaturated carboxylic acids such as ene-2,3-dicarboxylic acid, endo-cis-bicyclo[2,2,1]hept-5-ene-2-methyl-2,3-dicarboxylic acid, itaconic acid, citraconic acid, butenetricarboxylic acid, etc.; cyclic olefins containing epoxy groups such as epoxyhexylnorbornene, epoxycyclohexanenorbornene, methylglycidyl ethernorbornene, etc.; 2-(o-vinylphenyl)ethylene oxide, 2-(p-vinylphenyl)ethylene oxide, 2-(o-allylphenyl)ethylene oxide, 2-(p-allylphenyl)ethylene oxide, etc. Phenyl)ethylene oxide, 2-(o-vinylphenyl)propylene oxide, 2-(p-vinylphenyl)propylene oxide, 2-(o-allylphenyl)propylene oxide, 2-(p-allylphenyl)propylene oxide, p-glycidylstyrene, 3,4-epoxy-1-butene, 3,4-epoxy-3-methyl-1-butene, 3,4-epoxy-1-pentene, 3,4-epoxy-3-methyl-1-pentene, 5,6-epoxy-1-hexene, vinylcyclohexene monoxide, allyl-2,3-epoxycyclopentyl ether, 2,Monomers containing epoxy groups such as 3-epoxy-5-vinylnorbornane and 1,2-epoxy-4-vinylcyclohexane are used.

[0020] Examples of the monomer containing an amino group include aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, and cyclohexylaminoethyl (meth)acrylate.

[0021] Examples of the monomer containing a silane group include unsaturated silane compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetylsilane, and vinyltrichlorosilane.

[0022] Examples of monomers containing a hindered amine group include 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4-acryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1-butyl-2,2,6,6-tetramethylpiperidine, and 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine. 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4-methacryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1-butyl-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, and the like. The structural unit (B) derived from the polar group-containing monomer may be of one type or of multiple types.

[0023] (3) Structural unit (C) In addition to the above-mentioned monomers, other copolymerizable monomers may be copolymerized as needed to the extent that the properties of the polymer are not impaired, for example, norbornene, styrene, vinyl toluene, α-methylstyrene, vinyl naphthalene, acrylonitrile, methacrylonitrile, acetone acrylamide, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, chloroethyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, pentafluoropropyl (meth)acrylate, trifluoroethyl (meth)acrylate, and other vinyl compounds; and isoprene, pentadiene, butadiene, and other diene compounds may also be copolymerized and used. Furthermore, for the purpose of improving kneading processability and extrusion processability, polyfunctional (meth)acrylates or oligomers, for example, di(meth)acrylates of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, and 1,9-nonanediol, di(meth)acrylates such as neopentyl glycol, tetraethylene glycol, tripropylene glycol, and polypropylene glycol, bisphenol A-ethylene oxide adduct diacrylate, dimethyloltricyclodecane diacrylate, glycerin methacrylate acrylate, and 3-acryloyloxyglycerin monomethacrylate can also be copolymerized as monomers that provide structural unit (C).

[0024] The polar group-containing polyolefin resin (P) according to the present invention must contain at least one type of structural unit (A) and at least one type of structural unit (B), for a total of two or more types of monomer units, and may also contain another structural unit (C). The structural units and the amount of structural units in the polar group-containing polyolefin resin (P) according to the present invention will be explained. A structure derived from one molecule of structural unit (A) and one molecule of structural unit (B) are defined as one structural unit in the polar group-containing polyolefin resin (P). The amount of structural units is the ratio of each structural unit expressed in mol% when the total structural units in the polar group-containing polyolefin resin (P) are taken as 100 mol%.

[0025] Amount of structural units (A) derived from olefins: The structural unit amount of the structural unit (A) according to the present invention is 70.0 mol% or more, preferably 75.0 mol% or more, more preferably 80.0 mol% or more, even more preferably 85.0 mol% or more, even more preferably 90.0 mol% or more, particularly preferably 91.0 mol% or more, and the upper limit is 99.99 mol% or less, preferably 99.95 mol% or less, more preferably 99.25 mol% or less, even more preferably 99.0 mol% or less, even more preferably 98.75 mol% or less, particularly preferably 98.5 mol% or less, most preferably 98.0 mol% or less. If the structural unit amount derived from ethylene is less than 70.0 mol%, the rigidity of the polar group-containing polyolefin resin (P) may be poor, and if it is more than 99.99 mol%, the crystallinity of the polar group-containing polyolefin resin (P) may be high, which may cause warping during molding.

[0026] Amount of structural units (B) derived from monomers containing polar groups: The structural unit amount of the structural unit (B) according to the present invention is selected from the upper limit of 30.0 mol% or less, preferably 25.0 mol% or less, more preferably 20.0 mol% or less, even more preferably 15.0 mol% or less, even more preferably 10.0 mol% or less, and particularly preferably 9.0 mol% or less, and the lower limit is selected from the lower limit of 0.01 mol% or more, preferably 0.05 mol% or more, more preferably 0.75 mol% or more, even more preferably 1.0 mol% or more, even more preferably 1.25 mol% or more, particularly preferably 1.5 mol% or more, and most preferably 2.0 mol% or more. When the structural unit amount derived from the polar group-containing monomer (B) is 30.0 mol% or less, the polar group-containing polyolefin resin (P) has good adhesion to different materials, and when it is 0.01 mol% or more, it has excellent flexibility. The polar group-containing monomer (B) may be used alone or in combination of two or more types.

[0027] Amount of structural units (C) derived from other comonomers The upper limit of the amount of the structural unit (C) according to the present invention is selected from 20.0 mol% or less, preferably 15.0 mol% or less, more preferably 10.0 mol% or less, even more preferably 8.0 mol% or less, and particularly preferably 5.0 mol% or less, and there is no particular restriction on the lower limit, which may be 0 mol%. When the amount of structural units derived from any monomer (C) is 20.0 mol% or less, the polar group-containing polyolefin resin (P) tends to have sufficient mechanical properties. The monomers constituting the optionally used structural unit (C) may be used alone or in combination of two or more.

[0028] [2] Manufacturing method The method for producing the polar group-containing polyolefin resin (P) according to the present invention is not particularly limited, and various polymerization methods such as radical solution polymerization (Patent Documents 3-4), graft polymerization, graft modification, and polymerization using a catalyst (Patent Document 5) can be used as appropriate.

[0029] One method for producing a polar group-containing polyolefin resin (P) is a production method that utilizes high-pressure low-density polyethylene production equipment and technology. The polymerization reaction is carried out in the presence of at least one free radical polymerization initiator. The free radical polymerization initiator used in the radical polymerization is selected from compounds that generate free radicals, and examples of such initiators include oxygen, dialkyl peroxides such as di-tert-butyl peroxide, tert-butylcumyl peroxide, and dicumyl peroxide, diacyl peroxides such as acetyl peroxide, isobutyl peroxide, and octanoyl peroxide, peroxydicarbonates such as diisopropyl peroxydicarbonate and di(2-ethylhexylperoxy)dicarbonate, tert-butylperoxyisobutyrate, and tert-butyl peroxyisobutyrate. Examples of the polymerization initiator include peroxyesters such as ethyl peroxyneodecanate, tert-butyl peroxypivalate, and tert-butyl peroxylaurate, ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide, peroxyketals such as 1,1-bis-tert-butylperoxycyclohexane and 2,2-bis-tert-butylperoxyoctane, hydroperoxides such as tert-butyl hydroperoxide and cumene hydroperoxide, and azo compounds such as 2,2-azobisisobutyronitrile. The polymerization pressure is in the range of 70 to 350 MPa, preferably 100 to 250 MPa, and the polymerization temperature is in the range of 100 to 300°C, preferably 150 to 270°C.

[0030] Another method for producing the polar group-containing polyolefin resin (P) is a method of copolymerizing in the presence of a transition metal catalyst, for example, the method described in Patent Document 5.

[0031] Another method for producing the polar group-containing polyolefin resin (P) is graft modification. The graft modification method is not limited, but for example, a melt method in which a polyethylene resin in a molten state using an extruder or the like is reacted with a polar group-containing monomer using a reaction initiator, or a solution method in which a polyethylene resin is dissolved in a solvent and a polar group-containing monomer is reacted with a reaction initiator, are known. Either method can be suitably used, but the melt method is more suitably selected from the viewpoints of production cost and environmental load. When a polar group-containing monomer is introduced into a polyolefin molecular chain by graft modification, a polyolefin resin is used as a raw material. The polyolefin resin is an ethylene homopolymer or an ethylene-α-olefin copolymer obtained by polymerizing ethylene and a monomer selected from α-olefins having 3 to 20 carbon atoms. One type of polyethylene resin (B) may be used, but two or more types may also be used.

[0032] [3] Resin characteristics (1) Melt flow rate (MFR) The MFR (190 ° C, 21.18 N load) of the polar group-containing polyolefin resin (P) used in the present invention is 0.01 to 3000 g / 10 min, preferably 0.05 to 2500 g / 10 min, more preferably 0.1 to 1000 g / 10 min, more preferably 0.5 to 500 g / 10 min, even more preferably 1.0 to 200 g / 10 min, and even more preferably 1.5 to 100 g / 10 min. If the MFR of the resin is less than 0.01 g / 10 min, the resin flowability is poor, making it difficult for the resin to come out of the nozzle, resulting in poor molding properties. On the other hand, if it exceeds 3000 g / 10 min, the flowability is too high during 3D printing, making it difficult to maintain the shape, resulting in poor molding properties. The MFR of the polar group-containing polyolefin resin (P) is a value measured in accordance with JIS-K6922-2:2018 Appendix (190°C, 21.18N load).

[0033] (2) Weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn): The weight-average molecular weight (Mw) of the polar group-containing polyolefin resin (P) according to the present invention has a lower limit of usually 1,000 or more, preferably 6,000 or more, and more preferably 10,000 or more, and an upper limit of usually 2,000,000 or less, preferably 1,500,000 or less, even more preferably 1,000,000 or less, particularly preferably 800,000 or less, and most preferably 100,000 or less. If Mw is less than 1,000, the physical properties of the polar group-containing polyolefin resin (P), such as mechanical strength, impact resistance, and fluidity, may be insufficient. If Mw exceeds 2,000,000, the melt viscosity of the polar group-containing polyolefin resin (P) becomes very high, which may make molding of the polar group-containing polyolefin resin (P) difficult.

[0034] The weight average molecular weight (Mw) and number average molecular weight (Mn) in the present invention are determined by gel permeation chromatography (GPC). The molecular weight distribution parameter (Mw / Mn) is determined by determining the number average molecular weight (Mn) by gel permeation chromatography (GPC) and then calculating the ratio of Mw to Mn, Mw / Mn. An example of a GPC measurement method in the present invention is as follows.

[0035] 1) Measurement of weight average molecular weight (Mw) The weight average molecular weight (Mw) was determined by gel permeation chromatography (GPC). The molecular weight distribution parameter (Mw / Mn) was calculated by determining the number average molecular weight (Mn) by gel permeation chromatography (GPC) and then calculating the ratio of Mw to Mn, Mw / Mn. The measurement was carried out according to the following procedures and conditions.

[0036] 2) Preparation of sample solution Weigh out 3 mg of sample and 3 mL of o-dichlorobenzene into a 4 mL vial, cover with a screw cap and a Teflon (registered trademark) septum, and shake for 2 hours at 150°C using a Senshu Scientific SSC-7300 high-temperature shaker. After shaking, visually check that there are no insoluble components.

[0037] 3) Measurement A Waters Alliance GPCV2000 is connected to one RESONAC high-temperature GPC column, Showdex HT-G, and two HT-806M columns. The eluent is o-dichlorobenzene, and the measurement is performed at a temperature of 145°C and a flow rate of 1.0 mL / min.

[0038] 4) Calibration curve The column was calibrated using monodisperse polystyrene (S-7300, S-3900, S-1950, S-1460, S-1010, S-565, S-152, S-66.0, S-28.5, S-5.05, each 0.07 mg / ml solution) manufactured by RESONAC, n-eicosane, and n-tetracontane under the same conditions as above, and the elution time and the logarithm of the molecular weight were approximated by a quartic equation. The polystyrene molecular weight (MPS) and polyethylene molecular weight (MPE) were converted using the following equation: MPE=0.468×MPS

[0039] (3-i) Melting point (Tm, °C): The melting point of the polar group-containing polyolefin resin (P) of the present invention is indicated by the maximum peak temperature of the endothermic curve measured by a differential scanning calorimeter (DSC). When multiple peaks are observed in the endothermic curve obtained by DSC measurement, with heat flow (mW) on the vertical axis and temperature (°C) on the horizontal axis, the maximum peak temperature refers to the temperature of the peak with the greatest height from the baseline. In the case of a single peak, the maximum peak temperature refers to the temperature of that peak. In the present invention, the melting point can be determined, for example, using a DSC (DSC7020) manufactured by SII Nanotechnology Inc., by placing approximately 5.0 mg of a sample in an aluminum pan, heating it to 200°C at 10°C / min, holding it isothermally at 200°C for 5 minutes, cooling it to 20°C at 10°C / min, holding it isothermally at 20°C for 5 minutes, and then heating it again to 200°C at 10°C / min.

[0040] In the polar group-containing polyolefin resin (P) of the present invention, the lower limit of the melting point observed by differential scanning calorimetry (DSC) is preferably 30°C or higher, more preferably 40°C or higher, even more preferably 45°C or higher, even more preferably 50°C or higher, and even more preferably 55°C or higher, and the upper limit is preferably 140°C or lower, more preferably 130°C or lower, even more preferably 120°C or lower, particularly preferably 110°C or lower, and most preferably 105°C or lower. If the melting point is 30°C or lower, the rigidity of the polar group-containing polyolefin resin (P) may be insufficient. If the melting point is higher than 140°C, the volume after cooling is smaller than the volume at the time of melting, causing shrinkage and resulting in poor moldability.

[0041] (3-ii) Crystallinity (%): In the polar group-containing polyolefin resin (P) of the present invention, the lower limit of the crystallinity observed by differential scanning calorimetry (DSC) is not particularly limited, but is preferably greater than 0%. It is more preferably greater than 5%, and even more preferably 7% or greater. If the crystallinity is 0%, the rigidity of the polar group-containing polyolefin resin (P) may be insufficient. The upper limit of the crystallinity is preferably 50% or less. If the crystallinity exceeds 50%, the volume after cooling is smaller than the volume at the time of melting, causing shrinkage and resulting in poor moldability. In the present invention, the crystallinity can be determined by calculating the heat of fusion (ΔH) from the area of ​​the melting endothermic peak obtained by DSC measurement using the same procedure as in the melting point measurement described above, and dividing the heat of fusion by the heat of fusion of 293 J / g for perfectly crystalline high-density polyethylene (HDPE).

[0042] (4) Flexural modulus The copolymer of the present invention preferably has a flexural modulus of 1800 MPa or less, as measured in accordance with the appendix of JIS K6922-2:2018. It is more preferably 1600 MPa or less, even more preferably 1400 MPa or less, more preferably 1000 MPa or less, more preferably 800 MPa or less, and even more preferably 600 MPa or less. A flexural modulus within this range is preferred from the viewpoint of safety, since it has flexibility.

[0043] (5) Method for measuring the amount of polar group-containing monomer structural units The amount of structural units of the polar group-containing monomer according to the present invention is 1 H-NMR spectrum, 13 Measurement can be performed using C-NMR and FT-IR. The measurement method is a known method, and the amount of each structural unit can be calculated from the position and intensity of the signal or absorption peak. Particularly specific examples will be described in detail in the Examples.

[0044] (6) Formability The moldability of the present invention can be expressed by the degree of shrinkage that occurs during the resin cooling process. The degree of shrinkage can be expressed as a shrinkage percentage measured in accordance with JIS K 7152-4:2006. In 3D printing using the material extrusion method, if the resin shrinks and warps during the cooling process after extruding the molten resin, it will be impossible to produce a molded product as designed. Therefore, the shrinkage percentage measured in accordance with JIS K 7152-4:2006 is preferably 2.2% or less. It is more preferably 2.0% or less, even more preferably 1.8% or less, even more preferably 1.6% or less, and particularly preferably 0% to 1.4%. Note that since the resin of the present invention is a resin containing polyolefin, the shrinkage percentage will not be less than 0%. A shrinkage percentage within this range is preferable because the dimensional change that occurs during cooling is small, allowing the molded product to be formed as designed.

[0045] (7) Adhesiveness In the polar group-containing polyolefin resin (P) of the present invention, in order to ensure sufficient adhesion to dissimilar materials with high polarity, the adhesive strength to dissimilar materials measured by the adhesive strength measurement test described in the Examples below is preferably 0.3 N / 10 mm or more, more preferably 0.5 N / 10 mm or more, even more preferably 1.0 N / 10 mm or more, and particularly preferably 1.5 N / 10 mm or more.

[0046] [4] Resin composition for 3D printers One aspect of the present invention is a resin composition for 3D printers that contains the polar group-containing polyolefin resin (P). As a resin for 3D printers, one type of the polar group-containing polyolefin resin (P) may be used alone, or two or more types of polar group-containing polyolefin resins (P) may be mixed and used. By including the polar group-containing polyolefin resin (P) of the present invention in a resin composition for 3D printers, adhesion to different materials is imparted, and a resin is provided that has the properties required for 3D printer applications, such as no shrinkage or deformation. Furthermore, the resin has excellent flexibility, moldability, and low-temperature formability, making it possible to form shaped articles for 3D printer applications that have flexibility and low-temperature formability that could not be achieved with existing thermoplastic resins.

[0047] The polar group-containing polyolefin resin (P) can be optionally mixed with an appropriate known thermoplastic resin to form a resin composition for use in a 3D printer. Crystalline resins may also be added as long as low crystallinity suitable for 3D printer applications can be ensured. Resins that can be mixed with the polar group-containing polyolefin resin (P) include polyester, polyamide, polyimide, polyurethane, polyethylene, polypropylene, polyolefin, terephthalic acid derivative resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene, polyacetal, polyacrylate or ethylene-(meth)acrylate copolymer, modified ethylene-(meth)acrylate copolymer, halogenated polymers such as chlorinated polyethylene and polyvinyl chloride, and ionomers.

[0048] The blending ratio of the polar group-containing polyolefin resin (P) in the resin composition is 50% by mass or more, preferably 60% by mass or more, and more preferably 70% by mass or more, when the entire resin composition is taken as 100% by mass. The resin for 3D printers may be 100% by mass, i.e., made of the polar group-containing polyolefin resin (P). By using 50% by mass or more of the polar group-containing polyolefin resin (P), it is possible to form a shaped product that has the flexibility, shapeability, and low-temperature formability inherent to copolymers.

[0049] Additives The resin composition for 3D printers according to the present invention may contain additives commonly used in resins for 3D printers, such as conventionally known antioxidants, ultraviolet absorbers, lubricants, antistatic agents, colorants, pigments, crosslinking agents, foaming agents, nucleating agents, flame retardants, conductive materials, and fillers, within the scope of the present invention. The use of these additives is selected appropriately according to the purpose of modeling.

[0050] The resin composition for 3D printers according to the present invention can be obtained by kneading the polar group-containing polyolefin resin (P) with other resins or additives as needed by known means. The kneaded resin can be used in the form of pellets, or may be further processed into filaments.

[0051] ·filament Filaments of the resin composition for 3D printers can be formed by any method known in the art. For example, pellets of the 3D printer resin composition containing the polar group-containing polyolefin resin (P) can be fed into an extruder, extruded through a die in a molten state at a temperature higher than the peak melting temperature of the polar group-containing polyolefin resin (P), and then cooled to form a filament of the desired diameter. Filaments of any diameter can be obtained depending on the diameter of the extrusion die. Furthermore, the polar group-containing polyolefin resin (P) can further contain optional additives, such as plasticizers, stabilizers, antioxidants, UV absorbers, hydrolysis stabilizers, antioxidants, dyes or pigments, fillers, flame retardants, lubricants, processing aids, anti-blocking agents, release agents, and / or mixtures thereof, without departing from the spirit of the present invention.

[0052] A filament useful in the process for 3D printing is a filament containing the polar group-containing polyolefin resin (P) described herein, wound onto a coil or reel for feeding into the nozzle of a 3D printer. A cartridge containing the wound filament is attached to the 3D printer for use.

[0053] ·Process for making filaments The filaments, strands, or fibers described herein for use in fusion manufacturing processes can be formed by any method known in the art. For example, pellets containing the polar group-containing polyolefin resin (P) are fed into an extruder, where the temperature in the extruder is at least 10°C higher than the peak melting temperature of the polar group-containing polyolefin resin (P). The molten polymer composition is extruded through a die and subsequently cooled to form filaments, strands, or fibers of the desired diameter. While filaments of any diameter can be prepared, useful diameters are typically in the range of 1.3 to 3.0 mm. Preferably, the filament diameter is in the range of about 1.5 to 2.0 mm.

[0054] The resin composition containing the polar group-containing polyolefin resin (P) of the present invention can be used to produce an article by melt resin extrusion. This allows an article containing the resin composition containing the polar group-containing polyolefin resin (P) of the present invention to be molded using 3D printing technology. A method for producing a molded article by 3D printing includes the step of depositing the 3D printer resin composition containing the polar group-containing polyolefin resin (P) in multiple layers using a 3D printer to form an article.

[0055] The molten resin extrusion method, one of the 3D printing methods, can be used to model objects by fused filament deposition. In this method, a filament containing the polar group-containing polyolefin resin (P) is supplied through a nozzle heated to a sufficient temperature. The heating temperature is sufficient to melt the filament as long as it is equal to or higher than the melting point of the polar group-containing polyolefin resin (P). By including the polar group-containing polyolefin resin (P), the heating temperature can be kept relatively low. The molten filament emerges from the nozzle and is deposited in a multilayer shape, forming a desired shaped object. The deposition rate can be controlled by changing the filament feed rate, cross-sectional dimensions, and movement speed of the nozzle and / or the shaped object. Therefore, one aspect of the present invention relates to a 3D-printed object formed by depositing one or more lines by fused filament deposition using a 3D printer resin composition containing the polar group-containing polyolefin resin (P).

[0056] Laminates The laminate of the present invention is a laminate including at least a layer made of the resin for 3D printers of the present invention, and a layer made of an adherend laminated thereon.

[0057] ·Adherent The laminate of the present invention may be a laminate of a layer of a resin without polar groups, such as a polyolefin resin such as a polyethylene resin or a polypropylene resin, and a layer of the 3D printer resin of the present invention; however, in order to demonstrate the adhesive properties of the 3D printer resin of the present invention, it can be more advantageously used as a laminate with a layer of an adherend that is not easily bonded with polyolefin.

[0058] Examples of adherends that can be used in the present invention include polyolefin resins such as polyethylene resin and polypropylene resin, thermoplastic resins such as cycloolefin copolymer, polyvinyl chloride, polystyrene, polyamide resin, polyester resin, saponified ethylene-vinyl acetate copolymer resin (EVOH), polycarbonate, polyacetal, polyphenylene ether, and polyphenylene sulfide, metal materials such as aluminum, steel, and stainless steel, paper, cellophane, woven fabric, and nonwoven fabric.

[0059] Examples of polyolefin resins include high-density polyethylene, medium-density polyethylene, low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, ethylene-acrylic acid ester-maleic anhydride copolymer, ethylene-glycidyl methacrylate copolymer, ionomer, polypropylene resin, etc. These may be used alone or in combination of two or more.

[0060] Examples of polyamide resins include 6-nylon, 6,6-nylon, 6,10-nylon, 12-nylon, 11-nylon, 9-nylon, 7-nylon, polyamide 4,6, polyamide 6,12, polymetaxylylene adipamide, and various aromatic nylons, such as polyamide 6T, polyamide 9T, and polyamide 10T. The carboxyl or amino groups at the molecular chain terminals may be modified with other functional groups. These may be used alone or in combination of two or more.

[0061] Examples of polyester resins include aromatic ring-containing polyesters and aliphatic polyesters. Examples of aromatic ring-containing polyesters include poly-p-phenylene esters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene isophthalate, polybutylene isophthalate, poly-p-phenylene malonate, poly-p-phenylene adipate, and poly-p-phenylene terephthalate. Examples of aliphatic polyesters include polybutylene adipate, polyethylene adipate, poly-ε-caprolactone, polylactic acid, polybutylene succinate, polybutylene succinate adipate, and polyhydroxybutyrate. These may be used alone or in combination of two or more.

[0062] Polycarbonates are polymers or copolymers obtained by methods such as the phosgene process, in which various dihydroxydiaryl compounds are reacted with phosgene, or the transesterification process, in which a dihydroxydiaryl compound is reacted with a carbonate ester such as diphenyl carbonate. A representative example of these is an aromatic polycarbonate resin produced from 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) and phosgene. These may be used alone or in combination of two or more.

[0063] Examples of polyacetals include polyoxymethylene, polyoxyethylene, polyoxyphenylene (PPO), poly-1,3-dioxolane, etc. These may be used alone or in combination of two or more.

[0064] Polyphenylene ether is a synthetic resin having an aromatic polyether structure. Specific examples of polyphenylene ether resins include poly(2,6-dimethylphenylene-1,4-ether), poly(2-methyl-6-ethylphenylene-4-ether), poly(2,6-diethylphenylene-1,4-ether), poly(2,6-diethylphenylene-1,4-ether), poly(2-methyl-6-n-propylphenylene-1,4-ether), poly(2-methyl-6-n-butylphenylene-1,4-ether), poly(2-methyl-6-chlorophenylene-1,4-ether), poly(2-methyl-6-bromophenylene-1,4-ether), and poly(2-ethyl-6-chlorophenylene-1,4-ether). These may be used alone or in combination of two or more.

[0065] Polyphenylene sulfide is a high-performance engineering plastic with a molecular structure in which phenyl groups (benzene rings) and sulfur (S) are repeated alternately. These can be used alone or in combination of two or more types.

[0066] Examples of metals include aluminum, steel, stainless steel, copper, tin, brass, and mixtures, laminated structures, and composite materials thereof. Examples of aluminum that can be used include those described in JIS H4000-2017. More specific examples include A1100FD, A1200FD, A2014FD, A2017FD, A2018FD, AD2218FD, A2219FD, A2025FD, A4032FD, A5052FH, A5056FD, A5083FD, A6165FD, A6061FD, A7050FD, A7075FD, and A7N01FH. Examples of stainless steel include martensitic stainless steel, ferritic stainless steel, austenitic stainless steel, and austenitic-ferritic duplex stainless steel. More specific examples include SUS201, SUS202, SUS301, SUS302, SUS303, SUS304, SUS305, SUS316, SUS317, SUS403, SUS405, SUS420, SUS430, SUS430LX, SUS436, and SUS630. As the steel, for example, various steels, steel materials, cast and forged products, etc. described in JIS G0203 and JIS G0204 can be used without any particular restrictions, and these may be subjected to various surface treatments or plating. A laminate containing the resin composition for 3D printers of the present invention and using the above materials as adherends exhibits good adhesion. Adhesion can be evaluated by adhesive strength according to the method described in the Examples below. The adhesive strength to each adherend is preferably 10 N / 10 mm or more, and although there is no particular upper limit, it is preferably 500 N / 10 mm or less, more preferably 300 N / 10 mm or less, even more preferably 100 N / 10 mm or less, and even more preferably 80 N / 10 mm or less.

[0067] Laminate manufacturing method The manufacturing method of the present invention is not particularly limited, and known methods can be used. In the 3D printing process, a laminate may be formed by combining a polar group-containing polyolefin resin with a different material, or other known laminate manufacturing methods, such as press molding, extrusion molding, blow molding, pressure molding, vacuum molding, vacuum pressure molding, and insert molding using injection molding, can also be used. In any method, there is no particular limitation as long as it includes a step of first molding a 3D printing resin into a desired shape by 3D printing, and if necessary, remelting a portion of the molded object by heat and integrating it with a layer made of another adherend. [Example]

[0068] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The evaluation methods and resins used in the examples and comparative examples are as follows.

[0069] 1. Evaluation method for resin properties (1) Mw / Mn: 1) Measurement of weight average molecular weight (Mw) and molecular weight distribution parameter (Mw / Mn) The weight average molecular weight (Mw) was determined by gel permeation chromatography (GPC). The molecular weight distribution parameter (Mw / Mn) was calculated from the ratio of Mw to Mn, Mw / Mn, obtained by gel permeation chromatography (GPC) and then determining the number average molecular weight (Mn). The measurement was carried out according to the following procedures and conditions. 2) Preparation of sample solution 3 mg of sample and 3 mL of o-dichlorobenzene were weighed into a 4 mL vial, and the vial was capped with a screw cap and a Teflon (registered trademark) septum, and then shaken for 2 hours at 150°C using a Senshu Scientific SSC-7300 high-temperature shaker. After shaking, it was visually confirmed that there were no insoluble components. 3) Measurement A Waters Alliance GPCV2000 was connected to one RESONAC high-temperature GPC column, Showdex HT-G, and two HT-806M columns. Measurements were performed using o-dichlorobenzene as the eluent at a temperature of 145°C and a flow rate of 1.0 mL / min. 4) Calibration curve The column was calibrated using monodisperse polystyrene (S-7300, S-3900, S-1950, S-1460, S-1010, S-565, S-152, S-66.0, S-28.5, S-5.05, each 0.07 mg / ml solution) manufactured by RESONAC, n-eicosane, and n-tetracontane under the same conditions as above, and the elution time and the logarithm of the molecular weight were approximated by a quartic equation. The polystyrene molecular weight (MPS) and polyethylene molecular weight (MPE) were converted using the following equation: MPE=0.468×MPS

[0070] (2) Melting point and crystallinity: Measurements were carried out by DSC using a DSC7020 manufactured by SII Nano Technology Inc. in the same manner as described above.

[0071] (3) Melt flow rate (MFR): As described above, the MFR of the polar group-containing polyolefin resin (P) was measured in accordance with JIS-K6922-2:2018 (190°C, 21.18 N load).

[0072] (4) Flexural modulus: Test specimens were prepared in accordance with JIS K7151-1995, with a press temperature of 180°C and cooling according to cooling method A. The test specimens were cut into 4 x 10 x 80 mm pieces from 4.0 mm thick pressed sheets, and measurements were made in accordance with the JIS K7171-2:2016 Appendix.

[0073] (5) Shrinkage rate: In accordance with JIS K 7152-4:2006, a 120 x 120 x 2 mm flat plate with a film gate (gate thickness 0.2 mm) on one side was molded using a FANUC ROBOSHOT 2000i-100B injection molding machine at a molding temperature of 190°C and a mold temperature of 40°C, and the machine direction (MD) was measured immediately after molding. The measured value was divided by the length of the mold to calculate the shrinkage rate, with a shrinkage rate of 2.2% or less being rated as good, and a rate of more than 2.2% being rated as bad. [Preparation of test specimens] Standard number: JIS-7152 (ISO294-1) Molding machine: FANUC ROBOSHOT 2000i-100B injection molding machine Molding machine temperature setting: 30, 180, 190, 190, 190℃ from the bottom of the hopper Mold temperature: 40℃ Injection speed: 50 mm / sec (speed inside the mold cavity) Holding pressure: 30 MPa Pressure retention time: 10 seconds Mold shape: Flat plate (thickness 2 mm, width 120 mm, length 120 mm)

[0074] (6) Method for measuring the amount of polar group-containing monomer structural units The structural unit amount of the polar group-containing monomer is 1 H-NMR spectrum, 13 Measurements were performed using C-NMR and FT-IR. i) 1 H-NMR spectrum, 13 C-NMR measurements The amounts of acrylic acid, methacrylic acid, and t-butyl acrylate structural units in the polar-group-containing polyolefin resin (P) were measured using the following method. 200–250 mg of sample was placed in a 10 mm inner diameter NMR sample tube along with 2.4 ml of o-dichlorobenzene / deuterated bromide benzene (CDBr) = 4 / 1 (volume ratio) and hexamethyldisiloxane, a chemical shift reference material. The tube was then purged with nitrogen, sealed, and heated to dissolve the solution, resulting in a homogeneous solution for NMR measurement. NMR measurements were performed at 120 °C using a Bruker Biospin AV400M NMR instrument equipped with a 10 mm diameter cryoprobe. 1 H-NMR was measured at a pulse angle of 1°, a pulse interval of 1.8 seconds, and an accumulation count of at least 1,024. The chemical shift was set at 0.088 ppm for the methyl proton peak of hexamethyldisiloxane, and the chemical shifts of peaks due to other protons were based on this. 13 C-NMR was measured using the inverse gate decoupling method with a pulse angle of 90°, a pulse interval of 51.5 seconds, and an accumulation count of at least 512. The chemical shift was set to 1.98 ppm for the methyl carbon peak of hexamethyldisiloxane, and the chemical shifts of peaks due to other carbons were referenced to this.

[0075] 1) Sample pretreatment When the sample contained a carboxyl group, an esterification treatment such as methyl esterification using diazomethane or trimethylsilyl (TMS) diazomethane was appropriately performed.

[0076] 2) Calculation of the structural unit amounts of t-butyl acrylate, acrylic acid, and methacrylic acid <tba> The quaternary carbon signal of the t-butyl acrylate group of tBA is 13 It is detected at 79.6 to 78.8 in the C-NMR spectrum. Using these signal intensities, the amount of comonomer was calculated according to the following formula. Total amount of tBA (mol%) = I(tBA) × 100 / [I(tBA) + I(E)] Here, I(tBA) and I(E) are the quantities shown in the following formulas. I(tBA)=I 79.6~78.8 I(E)=(I 180.0~135.0 +I 120.0~5.0 -I(tBA)×7) / 2

[0077] <aa> The signal of the carbonyl carbon of acrylic acid (AA) is 1 It is detected at 2.5 to 2.3 in the H-NMR spectrum. Using these signal intensities, the amount of comonomer was calculated according to the following formula. Total amount of AA (mol%)=I(AA)×100 / [I(AA)+I(E)] Here, I(AA) and I(E) are the quantities shown in the following formulas. I(AA)=I2.5~2.3 I(E)=(I6.0~0-I(AA)×4) / 4

[0078] <maa> The carbonyl carbon signal of methacrylic acid (MAA) is 13 It is detected at 167.9 ppm in the C-NMR spectrum. Using these signal intensities, the amount of comonomer was calculated from the following formula in the same manner as for E / tBA. MAA content (mol%)=I (MAA) ×100 / (I (E) +I (MAA) ) where I (MAA) , I (E) are the quantities shown in the following equations, respectively. I (MAA) =I 167.9 I (E) =(I 180.0~136.0 +I 120.0~100.0 +I 55.0~2.0 -I (MAA) ×5) / 2

[0079] When the amount of structural units of each monomer is indicated by "<0.1" including an inequality sign, this means that the monomer is present as a structural unit in the copolymer, but the amount is less than 0.1 mol % taking into account significant digits.

[0080] ii) Measurement method using FT-IR The methyl acrylate, ethyl acrylate, and maleic anhydride in the polar group-containing polyolefin resin (P) were measured by the following method. <MA、EA> The (meth)acrylic acid ester / ethylene composition ratio (molar ratio) is initially 4600 cm -1 and 3500cm -1 The baseline was drawn at 4254 cm from ethylene. -1 The peak height (A4254) was measured. -1 A single baseline was drawn at 3457 cm derived from (meth)acrylic acid ester. -1 The peak height (A3457) was measured. Furthermore, the peak ratio (A3457 / A4254) was calculated, and the (meth)acrylic acid ester / ethylene composition ratio (molar ratio) was calculated using a calibration curve of the (meth)acrylic acid ester content and the IR absorbance ratio, which was separately prepared using NMR.

[0081] <Maleic anhydride> The maleic anhydride / ethylene composition ratio (molar ratio) is initially 4600 cm -1 and 3500cm -1 The baseline was drawn at 4254 cm from ethylene. -1 The peak height (A4254) was measured. -1 and 600cm -1 The baseline was drawn at 1783 cm derived from MAH. -1 The peak height (A1783) was measured. Furthermore, the maleic anhydride / ethylene composition ratio (molar ratio) was calculated from the peak ratio (A1783 / A4254) using a calibration curve prepared from the MAH content determined by NMR and the IR absorbance ratio separately described in "Japanese Patent Application No. 2022-048855 (JP Patent Publication No. 2023-142138)."

[0082] (7) Formability: Filaments were produced from the pellet-shaped resins of the following Examples and Comparative Examples using the following method, and then 3D printed objects were produced from the produced filaments.

[0083] <Filament production method> The pelletized resins of the Examples and Comparative Examples were fed into a 65 mm single-screw extruder. The barrel temperature was set to the optimum temperature for each resin, ranging from 70 to 240°C, depending on the specific Example or Comparative Example used. As the molten resin emerged from the die, it was quenched in a water bath at approximately 20°C. The quenched filament was wound onto a reel at controlled speed, producing a 1.75 mm diameter filament by adjusting the pulling speed to 21 m / min.

[0084] <Method for forming 3D printing products> In the examples described herein, a Raise3D Pro2 Plus 3D printer equipped with a standard direct drive extruder and a 0.5 mm nozzle was used with a nominal 1.75 mm filament to print a flat resin plate (100% fill factor) measuring 20 mm in length, 100 mm in width, and 0.5 mm in thickness under the following conditions: Model used: Raise3D Pro2 Plus Nozzle temperature: 190℃ Layer pitch: 0.2 mm Printing speed: 20mm / s Part shape and dimensions: Plate: 20mm x 100mm, thickness 2mm, filling rate 100% The resulting molded product was observed and evaluated for moldability according to the following criteria. 〇: Almost no warping and can be shaped beautifully. △: Shrinkage has occurred, but it can still be shaped. ×: The shrinkage is large and the model cannot be formed neatly.

[0085] (8) Adhesiveness Laminate preparation method The adhesive strength was measured by first creating a shape of the resin to be measured using a 3D printer, then overlapping it with the adherend and heat pressing or vacuum laminating it to create a laminate, and then conducting a peel test on the laminate. The adjustment method and measurement method for each process will be explained in order. 1) Preparation method of 3D printed resin plates for measuring adhesive strength Model used: Raise3D Pro2 Plus Nozzle temperature: 190℃ Layer pitch: 0.2 mm Printing speed: 20mm / s Shape and dimensions: 25mm x 100mm, thickness 2mm

[0086] (When the substrate is glass) How to adjust glass sheets The glass plates used were commercially available float glass plates manufactured by the float process. Before the test, the 2 mm thick float glass plates were washed with a neutral detergent, dried at 70°C, and cut to dimensions of 25 mm x 100 mm. The top surface of the glass was then bonded to the press plate of the sample. Method for manufacturing laminate of sample and glass plate Using a vacuum laminator (manufactured by NPC Corporation), the resin plate for adhesive strength measurement obtained by the resin plate preparation method described above and the top surface of the above plate glass were laminated under conditions of a heating temperature of 180°C for 10 minutes, and then sandwiched between two aluminum plates and quenched for 3 minutes to obtain a two-layer, two-type laminate. A 10 mm wide slit was made in the sheet part of this laminate to prepare a test specimen.

[0087] (When the adherend is aluminum) The resin plate for adhesive strength measurement obtained by the resin plate preparation method described above was overlapped with an adherend processed to 25 mm x 100 mm and a thickness of 60 μm, and the two were bonded together at a heating temperature of 180°C for 10 minutes to obtain a two-type, two-layer laminate. This laminate was then cut into 10 mm wide pieces to prepare test pieces.

[0088] (When the adherend is nylon film) The resin plate for adhesive strength measurement obtained by the resin plate preparation method described above was overlapped with an adherend processed to 25 mm x 100 mm and a thickness of 50 μm, and the two plates were heated at 180°C for 10 minutes, then sandwiched between two aluminum plates and quenched for 3 minutes to obtain a two-type, two-layer laminate. This laminate was then cut into 10 mm wide pieces to prepare test pieces.

[0089] (When the substrate is EVOH film (Kuraray F101B)) The resin plate for adhesive strength measurement obtained by the resin plate preparation method described above was overlapped with an adherend processed to 25 mm x 100 mm and a thickness of 50 μm, and the two plates were heated at 180°C for 10 minutes, then sandwiched between two aluminum plates and quenched for 3 minutes to obtain a two-type, two-layer laminate. This laminate was then cut into 10 mm wide pieces to prepare test pieces.

[0090] ·Adhesive strength measurement method The laminate obtained by the laminate preparation method was cut into a 10 mm wide strip near the center on the resin side only, and adhesive strength was measured using a tensile tester at a speed of 50 mm / min by 90° peeling for glass and T-peeling for aluminum, nylon film, and EVOH. The adhesive strength was measured in units of N / 10 mm.

[0091] <(Production Examples 1 to 8): Production of Carboxylic Acid-Containing Copolymer Precursor> Ethylene / tBu acrylate copolymers were produced using transition metal complexes (B-423 / Ni complex or B-27DM / Ni complex). The copolymers were produced with reference to Production Example 1 or Production Example 3 described in JP 2016-79408 A. The production conditions and production results, including the type and amount of metal complex, the amount of aluminum compound (trioctylaluminum (TNOA)), the amount of toluene, the type and amount of comonomer, the ethylene partial pressure, the polymerization temperature, and the polymerization time, were appropriately changed. Table 1 shows the production results, and Table 2 shows the physical properties of the resulting copolymers.

[0092] [Table 1]

[0093] [Table 2]

[0094] <(Examples 1 to 7, Comparative Example 1): Preparation of Carboxylic Acid-Containing Copolymer> A 500 ml separable flask was charged with 40 g of the polar group-containing polyolefin resin obtained in Production Examples 1 to 8, 0.8 g of paratoluenesulfonic acid monohydrate, and 185 ml of toluene, and the mixture was stirred at 105°C for 4 hours. 185 ml of ion-exchanged water was added, stirred, and allowed to stand, after which the aqueous layer was extracted. Subsequently, the addition and extraction of ion-exchanged water was repeated until the pH of the extracted aqueous layer reached 5 or higher. The solvent was distilled off from the remaining solution under reduced pressure, and the solution was dried to a constant weight. In the IR spectrum of the obtained resin, a 850 cm derivative of the tBu group was observed. -1 The disappearance of the peak around 1730 cm originating from the carbonyl group of the ester -1 The decrease in the peak near 1700 cm originates from the carbonyl group of the carboxylic acid (dimer). -1 An increase in the peak around The decomposition of t-Bu ester and the production of carboxylic acid were confirmed, and a carboxylic acid-containing copolymer was obtained. The physical properties of the resulting polar group-containing polyolefin resin are shown in Table 3.

[0095] <(Examples 8 and 9): Preparation of Carboxylic Acid-Containing Copolymer> Starting from ethylene and methyl methacrylate, a polar group-containing polyolefin resin was obtained by the high-pressure radical process and deesterification in the same manner as in Production Examples 1 to 8. The physical properties of the obtained resin are shown in Table 3.

[0096] [Table 3]

[0097] <(Examples 10 to 22): Preparation of ethylene, (meth)acrylate, and dicarboxylic acid anhydride-containing copolymer> Ethylene and comonomer were injected into a reactor of a high-pressure low-density polyethylene plant equipped with a 5 L autoclave. The production conditions, which were appropriately changed, including the reaction initiator, comonomer type, comonomer amount, ethylene partial pressure, and polymerization temperature, are shown in Table 4, and the physical properties of the resulting polar group-containing olefin copolymer are shown in Table 5.

[0098] [Table 4]

[0099] [Table 5]

[0100] The polar group-containing polyolefin resins used in Examples 23 to 26 and Comparative Examples 2 and 3 are shown below. Example 23: Bondfast CG5001 manufactured by Sumitomo Chemical Example 24: Bondfast BF-7M manufactured by Sumitomo Chemical Example 25: Novatec LV1511 manufactured by Nippon Polyethylene Example 26: Novatec LV780 manufactured by Nippon Polyethylene Comparative Example 2: KJ640T manufactured by Nippon Polyethylene Comparative Example 3: HE421 manufactured by Nippon Polyethylene

[0101] Example 27: Preparation of maleic anhydride grafted polyethylene resin 0.8 parts by weight of maleic anhydride and 0.016 parts by weight of 2,5-dimethyl-2,5-di-(t-butylperoxy)hexane were added to low-density polyethylene (Japan Polyethylene, product name: Metallocene Plastomer Kernel, grade name: KJ640T), and after thorough mixing in a Henschel mixer, the mixture was melt-kneaded in a 58 mm twin-screw extruder at a resin temperature of 280°C. The maleic anhydride content was measured by the FT-IR mentioned above, confirming that the mixture had been graft-modified. MFR: 28 g / 10 min, density: 0.881 g / cm 3 The physical properties of the resulting polar group-containing olefin copolymer are shown in Table 6.

[0102] [Table 6]

[0103] Table 7 shows the evaluation results of MFR, melting point, crystallinity, flexural modulus, shrinkage rate, and appearance of the molded article of Examples 1 to 27 and Comparative Examples 1 to 3, and Table 8 shows the evaluation results of adhesiveness.

[0104] [Table 7]

[0105] [Table 8]

[0106] <Results of Consideration of Examples and Comparative Examples> In Examples 1 to 27, the polyolefin resin contains polar groups, resulting in an increased amorphous content. This results in a small change in volume between melting and cooling, resulting in a small shrinkage rate. Warping and other issues do not occur during modeling using a 3D printer using the material extrusion method, resulting in good moldability. Adhesion to various materials was also good. On the other hand, Comparative Example 1 is copolymerized with a polar group-containing monomer, but the amount of polar group-containing monomer is insufficient, resulting in an increased crystalline content. This results in a large change in volume between melting and cooling, resulting in a high shrinkage rate. Regarding Comparative Example 2, since ethylene is polymerized with an α-olefin, the increased amorphous content makes warping less likely. However, the absence of polar groups results in poor adhesion to dissimilar materials. Comparative Example 3 does not contain polar groups, resulting in poor adhesion to dissimilar materials, and the increased crystalline content leads to significant warping and poor moldability. From the above, copolymers of olefins and polar group-containing monomers have low melting points, excellent moldability, ensure safety during molding, and also possess high adhesive strength.< / maa> < / aa> < / tba>

Claims

1. A resin composition for 3D printers, comprising: a polar-group-containing polyolefin resin (P) having a structural unit (A) derived from an olefin and a structural unit (B) derived from a monomer containing a polar group, wherein the polar-group-containing polyolefin resin contains 70 to 99.99 mol % of the structural unit (A) and 0.01 to 30 mol % of the structural unit (B); and a melt flow rate measured under conditions of a temperature of 190°C and a load of 2.16 kg of 0.01 to 3000 g / 10 min; and optionally a thermoplastic resin other than (P), wherein the amount of (P) is 50 mass % or more of the entire resin composition.

2. The structural unit (A) is derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 12 carbon atoms. The resin composition for 3D printers according to claim 1.

3. The structural unit (B) is derived from at least one selected from the group consisting of alkyl (meth)acrylates having an alkyl group having 1 to 8 carbon atoms, alkoxy (meth)acrylates having an alkoxyalkyl group having 2 to 8 carbon atoms, unsaturated carboxylic acids, unsaturated dicarboxylic acids, unsaturated dicarboxylic acid anhydrides, amino groups, silanol groups, and glycidyl groups. The resin composition for 3D printers according to claim 1, wherein the structural unit (B) is derived from at least one selected from the group consisting of alkyl (meth)acrylates having an alkyl group having 1 to 8 carbon atoms, alkoxy (meth)acrylates having an alkoxyalkyl group having 2 to 8 carbon atoms, unsaturated carboxylic acids, unsaturated dicarboxylic acid anhydrides, amino groups, silanol groups, and glycidyl groups.

4. The structural unit (B) is derived from at least one selected from the group consisting of unsaturated carboxylic acids, unsaturated dicarboxylic acids, and unsaturated dicarboxylic acid anhydrides. 3D printer resin composition according to claim 1.

5. 2. The resin composition for a 3D printer according to claim 1, wherein the polar group-containing polyolefin resin (P) is a polyolefin comprising the structural unit (A) graft-modified with the structural unit (B).

6. 2. The resin composition for 3D printers according to claim 1, wherein the resin composition is formed into a flat plate having a thickness of 0.5 mm, and the plate is laminated on a 25 mm x 100 mm aluminum plate at a heating temperature of 180°C for a heating time of 10 minutes. A test piece is cut out to a width of 10 mm, and when measured by T-peel using a tensile tester, the adhesive strength of the resin composition for 3D printers is 10 N / 10 mm or more.

7. The resin composition for 3D printers according to claim 1, wherein the melting point of the polar group-containing polyolefin resin (P) is 140°C or lower.

8. The resin composition for 3D printers according to claim 1, wherein the melting point of the polar group-containing polyolefin resin (P) is 30°C or higher.

9. The resin composition for 3D printers according to claim 1, wherein the polar group-containing polyolefin resin (P) has a flexural modulus of 1800 MPa or less.

10. The resin composition for 3D printers according to claim 1, wherein the crystallinity of the polar group-containing polyolefin resin (P) is 50% or less.

11. A 3D printed product, characterized in that the resin composition for a 3D printer according to any one of claims 1 to 10 is deposited in a molten state into one or more lines.

12. A 3D printed product comprising a deposition layer formed by depositing the resin composition for 3D printers according to any one of claims 1 to 10 in a molten state in one or more lines, and an adherend layer to which the deposition layer is adhered.

13. A laminate comprising at least a layer made of the resin composition for 3D printers according to any one of claims 1 to 10 and an adherend layer.

14. A method for producing a laminate, comprising the steps of: heating the resin composition for 3D printers according to any one of claims 1 to 10 to a molten state using a 3D printer; depositing the molten resin composition in a plurality of layers to form a shaped article; cooling and solidifying the shaped article; and adhering the 3D printed article formed by these steps to an adherend layer.

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