3-methyl-1-butene copolymer, its production method, and 3-methyl-1-butene copolymer composition

Abstract

To provide a 3-methyl-1-butene copolymer and a 3-methyl-1-butene copolymer composition which can suppress thermal deterioration during processing while having excellent heat resistance and have both toughness and strength, and to provide a method for producing the 3-methyl-1-butene copolymer.SOLUTION: There is provided 3-methyl-1-butene copolymer which contains 3-methyl-1-butene copolymer resin, and has a melting point of 265.0 to 290.0°C, wherein breaking elongation X (%) and yield strength Y (MPa) measured in accordance with JIS K7161-1:2014 satisfy the following formula (1): Y>(-X / 16)+42.5...Formula (1).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a 3-methyl-1-butene copolymer, a method for producing the same, and a 3-methyl-1-butene copolymer composition. [Background technology]

[0002] 3-Methyl-1-butene polymers are widely known as high-melting-point polyolefins that can have a melting point of approximately 305°C. Therefore, 3-methyl-1-butene polymers require high processing temperatures, which may result in resin degradation during processing. To prevent resin degradation during processing, known techniques are available for lowering the melting point of 3-methyl-1-butene polymers to broaden the processing temperature range. For example, techniques have been devised to lower the melting point of the polymer by copolymerization (see, for example, Patent Document 1). However, although copolymerizing 3-methyl-1-butene polymers improves toughness, as measured by tensile elongation, by lowering the melting point, a problem of reduced mechanical properties, such as tensile strength, has arisen.

[0003] On the other hand, as a method for achieving both toughness and strength in a polymer, for example, a multi-stage polymerization method for obtaining a composition with a varied copolymerization composition is known (for example, Patent Document 2). Patent Document 2 discloses a composition comprising three types of 3-methyl-1-butene polymers with different heats of fusion, with the aim of achieving excellent heat resistance and extensibility represented by the Vicat softening point, and excellent mechanical strength such as impact strength and tear strength, and discloses that the composition is produced by a three-stage polymerization method. Another method for achieving both toughness and strength in a polymer is known to involve, for example, multi-stage addition of hydrogen (see, for example, Patent Documents 3 to 5). Patent Document 3 discloses a polymerization method in which ethylene homopolymerization or ethylene copolymerization with an α-olefin is carried out in two stages in the presence of hydrogen, in which the amount of hydrogen added is changed in each stage to obtain polymers with different viscosity average molecular weights. Patent Document 4 also discloses a polypropylene having high fluidity, a high melting point, and high crystallinity. Specifically, Patent Document 4 discloses that the polypropylene preferably comprises a polypropylene component A having high fluidity and high stereoregularity and a polypropylene component B having low fluidity and high stereoregularity, and that the polypropylene component A and the polypropylene component B can be produced by multistage polymerization while changing the amount of hydrogen added. Furthermore, Patent Document 5 discloses a method for producing a composition containing two or more branched α-olefin polymers having different intrinsic viscosities by a multi-stage polymerization process, in which the amount of hydrogen added is changed in each stage. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 61-103910 [Patent Document 2] JP-A-64-143 [Patent Document 3] Japanese Patent Application Publication No. 56-22304 [Patent Document 4] Japanese Patent Application Publication No. 6-329726 [Patent Document 5] Japanese Patent Application Publication No. 63-20307 Summary of the Invention [Problem to be solved by the invention]

[0005] The composition comprising a 3-methyl-1-butene polymer disclosed in Patent Document 2 is excellent in stretchability and mechanical strength such as impact strength and tear strength, but does not sufficiently lower the melting point. Furthermore, the technology disclosed in Patent Document 2 tends to reduce the transparency of the polymer. Patent Document 3 does not consider polymers using 3-methyl-1-butene as a monomer. Patent Documents 4 and 5 describe that 3-methyl-1-butene can be used as a monomer, but do not specifically disclose examples using this monomer or the effects thereof. Therefore, the present invention provides a 3-methyl-1-butene copolymer and a 3-methyl-1-butene copolymer composition that have excellent heat resistance, can suppress thermal degradation during processing, and achieve both toughness and strength, and a method for producing the 3-methyl-1-butene copolymer. [Means for solving the problem]

[0006] As a result of intensive research to solve the above problems, the present inventors have conceived the following invention and found that the problems can be solved. That is, the present invention is as follows.

[0007] [1] A 3-methyl-1-butene copolymer containing a 3-methyl-1-butene copolymer resin, having a melting point of 265.0 to 290.0°C, and having a breaking elongation X (%) and a yield strength Y (MPa) measured in accordance with JIS K 7161-1:2014 that satisfy the following formula (1): Y>(-X / 16)+42.5 Equation (1) [2] The 3-methyl-1-butene copolymer resin is a resin obtained by a multistage polymerization method, the multi-stage polymerization method includes a first step and a second step, In the first step, the shear rate measured by capillography at 320 ° C was 1216 sec -1 3-methyl-1-butene copolymer resin having a melt viscosity of 100 to 200 Pa·s at The 3-methyl-1-butene copolymer according to [1] above, which is obtained by further polymerizing the 3-methyl-1-butene copolymer resin produced in the first step in the second step. [3] The 3-methyl-1-butene copolymer according to [1] or [2] above, wherein the 3-methyl-1-butene copolymer resin is a copolymer of 3-methyl-1-butene and an α-olefin having 2 to 20 carbon atoms. [4] The 3-methyl-1-butene copolymer according to [3] above, wherein the content of structural units derived from the α-olefin in the 3-methyl-1-butene copolymer is more than 0 mol% and 20 mol% or less. [5] a first step of polymerizing 3-methyl-1-butene by continuously supplying hydrogen at a hydrogen flow rate of 0.01 to 75 mL / (h·L) per unit volume based on the initial charged volume of the 3-methyl-1-butene; and a second step of polymerizing 3-methyl-1-butene by continuously supplying hydrogen at a hydrogen flow rate of 50 to 1000 mL / (h L) per unit volume based on the initial charged volume of 3-methyl-1-butene used in the first step; A method for producing a 3-methyl-1-butene copolymer, wherein the hydrogen flow rate in the first step is different from the hydrogen flow rate in the second step. [6] A 3-methyl-1-butene copolymer composition containing a 3-methyl-1-butene copolymer resin, having a melting point of 265.0 to 290.0°C, and having a breaking elongation X (%) and a yield strength Y (MPa) measured in accordance with JIS K 7161-1:2014 that satisfy the following formula (1): Y>(-X / 16)+42.5 Equation (1) [7] The 3-methyl-1-butene copolymer composition according to [6] above, which contains at least one of the 3-methyl-1-butene copolymer resins having a melt viscosity of 100 to 200 Pa s at a shear rate of 1216 sec-1 measured by capillography at 320°C. [8] A resin composition comprising at least one selected from the group consisting of the 3-methyl-1-butene copolymer described in any one of [1] to [4] above and the 3-methyl-1-butene copolymer composition described in [6] or [7] above.

[0008] Furthermore, the following embodiments are also preferred. [9] The 3-methyl-1-butene copolymer composition according to [6] or [7] above, wherein the 3-methyl-1-butene copolymer resin is a copolymer of 3-methyl-1-butene and an α-olefin having 2 to 20 carbon atoms.

[10] The 3-methyl-1-butene copolymer composition according to [9] above, wherein the content of structural units derived from the α-olefin in the 3-methyl-1-butene copolymer composition is more than 0 mol% and 20 mol% or less. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a 3-methyl-1-butene copolymer and a 3-methyl-1-butene copolymer composition that have excellent heat resistance, can suppress thermal degradation during processing, and achieve both toughness and strength, as well as a method for producing the 3-methyl-1-butene copolymer. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described below based on an example of an embodiment. However, the embodiment shown below is an example for embodying the technical idea of ​​the present invention, and the present invention is not limited to the following description. In addition, although preferred embodiments are shown in this specification, a combination of two or more of the individual preferred embodiments is also a preferred embodiment. When there are several numerical ranges for matters shown as numerical ranges, the lower limit and upper limit can be selectively combined to form a preferred embodiment. In this specification, when a numerical range is stated as "XX to YY", it means "XX or more and YY or less."

[0011] The 3-methyl-1-butene copolymer of the present embodiment contains a 3-methyl-1-butene copolymer resin, has a melting point of 265.0 to 290.0°C, and is characterized in that the breaking elongation X (%) and yield strength Y (MPa) measured in accordance with JIS K 7161-1:2014 satisfy the following formula (1): Y>(-X / 16)+42.5 Equation (1) The 3-methyl-1-butene copolymer composition of the present embodiment (hereinafter also referred to as "copolymer composition") contains a 3-methyl-1-butene copolymer resin, has a melting point of 265.0 to 290.0°C, and is characterized in that the breaking elongation X (%) and yield strength Y (MPa) measured in accordance with JIS K 7161-1:2014 satisfy the following formula (1): Y>(-X / 16)+42.5 Equation (1) The 3-methyl-1-butene copolymer and copolymer composition of this embodiment can achieve both toughness and strength by satisfying the above formula (1). That is, the 3-methyl-1-butene copolymer and copolymer composition have high mechanical properties such as tensile strength, making them useful as molded parts, and are expected to provide excellent toughness as measured by tensile elongation and excellent impact resistance for molded articles. Furthermore, the 3-methyl-1-butene copolymer and copolymer composition have a melting point within a specific range, which allows them to have excellent heat resistance while suppressing thermal degradation during processing. That is, the 3-methyl-1-butene copolymer and copolymer composition can be easily molded over a wide range of processing temperatures while maintaining excellent heat resistance. Additionally, it is expected that the generation of decomposition gases during melt-kneading will be suppressed, resulting in excellent moldability. In this embodiment, the term "3-methyl-1-butene copolymer" refers to a polymer produced by a series of polymerization reactions in the same polymerization reactor, and contains two or more copolymers of 3-methyl-1-butene and unsaturated hydrocarbons. The term "3-methyl-1-butene copolymer composition" refers to a composition containing two or more copolymers of 3-methyl-1-butene and unsaturated hydrocarbons produced in separate polymerization reactors. The term "3-methyl-1-butene copolymer resin" (hereinafter also referred to as "copolymer resin") refers to the copolymer of 3-methyl-1-butene and unsaturated hydrocarbons contained in the 3-methyl-1-butene copolymer and the 3-methyl-1-butene copolymer composition.

[0012] <3-Methyl-1-butene Copolymer and Copolymer Composition> [Melting point] The 3-methyl-1-butene copolymer and copolymer composition have a melting point of 265.0 to 290.0°C. If the melting point of the 3-methyl-1-butene copolymer or copolymer composition is lower than 265.0°C, the heat resistance will be insufficient. If the melting point of the 3-methyl-1-butene copolymer or copolymer composition is higher than 290.0°C, the processing temperature will need to be increased, which may result in significant thermal degradation during processing. From the viewpoint of easily achieving a balance between even better heat resistance and a wide range of processing temperatures, the melting point of the 3-methyl-1-butene copolymer and copolymer composition is preferably 270.0 to 290.0°C, more preferably 275.0 to 290.0°C. The melting point can be adjusted by the type and content of monomers other than 3-methyl-1-butene, and the addition and content of crystallinity control additives such as crystal nucleating agents and crystal retarders. The melting point can be measured by the method described in the Examples.

[0013] [Formula (1)] The 3-methyl-1-butene copolymer and the copolymer composition have a breaking elongation X (%) and a yield strength Y (MPa) measured in accordance with JIS K 7161-1:2014 that satisfy the following formula (1). Y>(-X / 16)+42.5 Equation (1) If the 3-methyl-1-butene copolymer and copolymer composition do not satisfy the above formula (1), the balance of mechanical properties of the molded article will be poor, and the strength and / or impact resistance will be insufficient. The above formula (1) was derived from the balance between toughness and strength of the molded body based on the examples and comparative examples. Specifically, using the values ​​of the breaking elongation and yield elongation obtained in the examples and comparative examples, the horizontal axis was the breaking elongation and the vertical axis was the yield strength, and a straight line and its slope were determined from a plot that showed excellent values ​​for both breaking elongation and yield elongation, and formula (1) was obtained. In general, when the melting point of a 3-methyl-1-butene copolymer or copolymer composition is lowered, the toughness improves but the strength tends to decrease. However, the 3-methyl-1-butene copolymer or copolymer composition of the present embodiment has the above-mentioned melting point and satisfies formula (1), thereby achieving an excellent balance between toughness and strength.

[0014] The lower limit of the breaking elongation X of the 3-methyl-1-butene copolymer and copolymer composition is preferably 5% or more, more preferably 10% or more, and even more preferably 15% or more. The upper limit of the breaking elongation X is preferably 200% or less, more preferably 100% or less, even more preferably 50% or less, and even more preferably 35% or less. That is, the breaking elongation X is preferably 5 to 200%. The breaking elongation X can be adjusted by the amount of hydrogen or comonomer added in the polymerization reaction, the time and timing of addition, the method of addition, and the like.

[0015] The yield strength Y of the 3-methyl-1-butene copolymer and the copolymer composition is preferably 35 to 50 MPa, more preferably 40 to 50 MPa. The yield strength Y can be adjusted by the amount of hydrogen or comonomer added in the polymerization reaction, the time and timing of addition, the method of addition, and the like. The breaking elongation X and yield strength Y are measured in accordance with JIS K 7161-1:2014, and more specifically, can be measured by the method described in the Examples. In the Examples, when measuring the breaking elongation and yield strength, additives such as an alkyl radical scavenger and an antioxidant are added to the 3-methyl-1-butene copolymer and copolymer composition to prepare test specimens. Because the 3-methyl-1-butene polymer is poorly soluble in solvents and has a high melting point, it is susceptible to thermal degradation due to high-temperature processing. Therefore, when preparing test specimens, the additives are added to prevent the thermal degradation.

[0016] [Melt viscosity] The 3-methyl-1-butene copolymer and copolymer composition were measured at 320°C and a shear rate of 1216 sec -1 The melt viscosity at this time is preferably 30 to 300 Pa s, more preferably 50 to 150 Pa s. When the melt viscosity of the 3-methyl-1-butene copolymer and copolymer composition is within the above-mentioned range, the 3-methyl-1-butene copolymer and copolymer composition have a good balance between moldability and mechanical properties, which is preferable. In this embodiment, the melt viscosity can be measured by the method described in the Examples. In the Examples, additives such as an alkyl radical scavenger and an antioxidant are added when measuring the melt viscosity of a 3-methyl-1-butene copolymer, a copolymer composition, and a copolymer resin. Because a 3-methyl-1-butene polymer is poorly soluble in a solvent and has a high melting point, it may be thermally deteriorated during melt viscosity measurement, resulting in a change in melt viscosity. Therefore, in order to measure the original melt viscosity, the 3-methyl-1-butene copolymer, the copolymer composition, and the copolymer resin are thermally stabilized by the additives, thereby preventing a change in melt viscosity.

[0017] [Copolymer resin] The copolymer resin is a 3-methyl-1-butene copolymer and a copolymer of 3-methyl-1-butene and an unsaturated hydrocarbon contained in the copolymer composition. The unsaturated hydrocarbon may be, for example, an α-olefin. From the viewpoint of being able to suitably exhibit the physical properties of 3-methyl-1-butene and having good copolymerizability, the copolymer resin is preferably a copolymer of 3-methyl-1-butene and an α-olefin having 2 to 20 carbon atoms.

[0018] The content of structural units derived from an α-olefin in the 3-methyl-1-butene copolymer and the copolymer composition is preferably more than 0 mol % and 20 mol % or less. From the viewpoint of suitably exhibiting the physical properties of the α-olefin, the content of structural units derived from the α-olefin in the 3-methyl-1-butene copolymer and copolymer composition is more preferably 0.1 mol % or more, and even more preferably 0.5 mol % or more. Furthermore, from the viewpoint of suitably maintaining the physical properties of 3-methyl-1-butene, the content of structural units derived from α-olefins in the 3-methyl-1-butene copolymer and copolymer composition is more preferably 15 mol% or less, and even more preferably 10 mol% or less. The content of the structural unit derived from an α-olefin in the 3-methyl-1-butene copolymer and the copolymer composition can be determined by a Fourier transform infrared spectrophotometer (FT-IR). Specifically, it can be measured by the method described in the examples.

[0019] From the viewpoint of suitably exhibiting the physical properties of 3-methyl-1-butene, the α-olefin having 2 to 20 carbon atoms is preferably an α-olefin having 4 to 16 carbon atoms, and more preferably an α-olefin having 4 to 12 carbon atoms. In addition, the α-olefin having 2 to 20 carbon atoms may be linear or branched.

[0020] Examples of the α-olefins having 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, vinylcyclohexene, and vinylnorbornane. The α-olefins having 2 to 20 carbon atoms may be used alone or in combination of two or more.

[0021] <Method of producing 3-methyl-1-butene copolymer> [Multi-stage polymerization method] The 3-methyl-1-butene copolymer of this embodiment is a polymer produced by a series of polymerization reactions in the same polymerization reactor, and is a polymer containing two or more copolymers of 3-methyl-1-butene and unsaturated hydrocarbons, and can be produced, for example, by a multistage polymerization method. The above-mentioned "copolymer of 3-methyl-1-butene and unsaturated hydrocarbon" has the same meaning as the above-mentioned copolymer resin. That is, a polymer (3-methyl-1-butene copolymer) containing two or more copolymer resins can be produced by a series of polymerization reactions carried out in the same polymerization reactor by the multistage polymerization method. In a preferred example of this embodiment, the copolymer resin is a resin obtained in each step of a multi-stage polymerization method, the multi-stage polymerization method including a first step and a second step, and in the first step, a shear rate of 1216 sec measured by capillography at 320°C is -1 In a second step, a 3-methyl-1-butene copolymer resin having a melt viscosity of 100 to 200 Pa s is produced, and in a second step, the 3-methyl-1-butene copolymer resin produced in the first step is further polymerized to produce a 3-methyl-1-butene copolymer. The multi-stage polymerization method is not limited to the two stages of the first and second steps, but may have three or more polymerization stages.

[0022] The copolymer resin produced in the first step has a melt viscosity of 100 to 200 Pa·s, which is preferable because it has an excellent balance between mechanical strength and impact resistance. From the viewpoint of the balance between mechanical strength and impact resistance, the melt viscosity of the copolymer resin produced in the first step is more preferably 120 to 200 Pa·s, and even more preferably 120 to 180 Pa·s. In the second step, the copolymer resin produced in the first step is further polymerized, thereby dispersing the copolymer resin produced in the second step in the copolymer resin produced in the first step. At this time, by adjusting the amount of a molecular weight modifier such as hydrogen supplied in the first step and the second step, 3-methyl-1-butene copolymer resins having different physical properties such as melt viscosity can be produced in each step. It is difficult to specify the melt viscosity of the copolymer resin produced in the second step alone, because the copolymer resin produced in the second step necessarily contains the copolymer resin produced in the first step.

[0023] (hydrogen flow rate) In the above multi-stage polymerization method, it is preferable to adjust the amount of hydrogen supplied in the first step and the second step. That is, the method for producing a 3-methyl-1-butene copolymer of the present embodiment includes a first step in which 3-methyl-1-butene is used and hydrogen is continuously supplied and polymerized at a hydrogen flow rate per unit volume of 0.01 to 75 mL / (h L) based on the initial charge volume of 3-methyl-1-butene, and a second step in which hydrogen is continuously supplied and polymerized at a hydrogen flow rate per unit volume of 50 to 1000 mL / (h L) based on the initial charge volume of 3-methyl-1-butene used in the first step, wherein the hydrogen flow rate in the first step is different from the hydrogen flow rate in the second step.

[0024] In the first step, the hydrogen flow rate per unit volume based on the initial charged volume of 3-methyl-1-butene is 0.01 to 75 mL / (h·L), which is preferable because it provides an excellent balance between reactivity and mechanical properties. From the viewpoint of the balance between reactivity and mechanical properties, the hydrogen flow rate in the first step is more preferably 1 to 75 mL / (h·L), and even more preferably 1 to 65 mL / (h·L). In the second step, the hydrogen flow rate per unit volume based on the initial charged volume of 3-methyl-1-butene used in the first step is 50 to 1000 mL / (h·L), which is preferable because it provides an excellent balance between reactivity and mechanical properties. From the viewpoint of a balance between reactivity and mechanical properties, the hydrogen flow rate in the second step is more preferably 50 to 500 mL / (h L), and even more preferably 65 to 500 mL / (h L). From the viewpoint of a balance between reactivity and mechanical properties, the hydrogen flow rate in the second step is more preferably higher than the hydrogen flow rate in the first step. In the multi-stage polymerization method, the catalyst and polymerization conditions described below can be preferably used.

[0025] <Method of producing copolymer composition> [Mixing two or more copolymer resins] The 3-methyl-1-butene copolymer composition of this embodiment is a composition obtained by blending two or more copolymers of 3-methyl-1-butene and an unsaturated hydrocarbon, each produced in a separate polymerization reactor. The "copolymer of 3-methyl-1-butene and an unsaturated hydrocarbon" has the same meaning as the copolymer resin. The copolymer composition can be produced, for example, by mixing two or more of the copolymer resins produced in separate polymerization reactors. The mixing may be performed, for example, by simply mixing powders or pellets of the two or more copolymer resins, or by melt-kneading and mixing them.

[0026] In the above-mentioned mixing method, the two or more copolymer resins preferably have different melt viscosities. Specifically, the 3-methyl-1-butene copolymer composition of the present embodiment has a shear rate of 1216 sec measured by capillography at 320°C. -1 It is preferable that at least one 3-methyl-1-butene copolymer resin having a melt viscosity of 100 to 200 Pa·s at this temperature is blended. In the mixing method, it is preferable that the melt viscosity of at least one of the two or more copolymer resins is 100 to 200 Pa s, since this provides an excellent balance between mechanical strength and impact resistance. From the viewpoint of the balance between mechanical strength and impact resistance, the melt viscosity of the at least one copolymer resin is more preferably 120 to 200 Pa s, and even more preferably 120 to 180 Pa s.

[0027] In the mixing method, the melt viscosity of at least one copolymer resin, which is different from the "3-methyl-1-butene copolymer resin having a melt viscosity of 100 to 200 Pa s," among the two or more copolymer resins is preferably 10 to 150 Pa s, more preferably 30 to 150 Pa s, and even more preferably 30 to 140 Pa s. A melt viscosity of 10 to 150 Pa s facilitates excellent processability during molding, which is preferable.

[0028] After mixing two or more copolymer resins having different melt viscosities, it is difficult to determine the melt viscosity of each copolymer resin alone, because it is difficult to separate and measure the two or more copolymer resins after mixing. In the method of mixing two or more copolymer resins, the catalyst and polymerization conditions described below can be preferably used.

[0029] [catalyst] (polymerization catalyst) In both the multistage polymerization method and the method of mixing two or more copolymer resins, the polymerization reaction using 3-methyl-1-butene (hereinafter simply referred to as "polymerization reaction") is not particularly limited, and can be carried out using a catalyst containing a compound having a transition metal atom of Group 4 of the periodic table. In particular, the polymerization of 3-methyl-1-butene is preferably carried out in the presence of well-known catalysts such as metallocene catalysts and Ziegler-Natta catalysts. Specific examples of the transition metal atom of Group 4 of the periodic table used in the catalyst include titanium, zirconium, and hafnium, with titanium being preferred.

[0030] The catalyst containing a compound having a transition metal atom of Group 4 of the periodic table may be supplied to the polymerization reaction system as a solid, or may be supplied to the polymerization reaction system after being suspended or dissolved in an inert organic solvent (preferably a saturated aliphatic hydrocarbon).

[0031] The catalyst is preferably a supported catalyst supported on a carrier. A preferred example of the supported catalyst is a magnesium-supported titanium catalyst, which is a so-called Ziegler-Natta catalyst, in which the compound having a transition metal atom of Group 4 of the periodic table is titanium chloride and the support is magnesium chloride. Specifically, the magnesium-supported titanium catalyst is a solid one obtained by contacting a magnesium compound suspended in an inert hydrocarbon solvent with a liquid titanium compound and, if necessary, an electron donor compound having an ester or ether bond. The magnesium-supported titanium catalyst contains titanium atoms, magnesium atoms, halogen atoms, and multiple ester or ether bonds.

[0032] Examples of inert hydrocarbon solvents used in the production of the magnesium-supported titanium catalyst include hexane, decane, and dodecane. Examples of magnesium compounds include anhydrous magnesium chloride, diethoxymagnesium, and methoxymagnesium chloride. Examples of electron donor compounds having an ester bond via multiple atoms include alkyl benzoate (the alkyl group preferably has 1 to 8 carbon atoms), alkyl p-toluate (the alkyl group preferably has 1 to 8 carbon atoms), alkyl pivalate (the alkyl group preferably has 1 to 8 carbon atoms), dialkyl phthalate (the alkyl group preferably has 1 to 8 carbon atoms), dialkyl malonate (the alkyl group preferably has 1 to 8 carbon atoms), and dialkyl succinate (the alkyl group preferably has 1 to 8 carbon atoms). Examples of electron donor compounds having an ether bond via multiple atoms include 2-isobutyl-2-isopropyl-1,3-dimethoxypropane and 2-isopentyl-2-isopropyl-1,3-dimethoxypropane.

[0033] The molar ratio of halogen atoms to titanium atoms (halogen atoms / titanium atoms) in the magnesium-supported titanium catalyst is usually 2 to 100, and preferably 4 to 90. The molar ratio of electron donor compounds having an ester bond or an ether bond to titanium atoms (electron donor compounds / titanium atoms) in the magnesium-supported titanium catalyst is usually 0.01 to 100, and preferably 0.2 to 10. The atomic ratio of magnesium atoms to titanium atoms (magnesium atoms / titanium atoms) in the magnesium-supported titanium catalyst is usually 2 to 100, and preferably 4 to 50.

[0034] When the polymerization reaction is carried out by a liquid phase polymerization method, the solid titanium catalyst is preferably used in an amount of usually 0.001 to 2 millimoles, preferably 0.005 to 1 millimoles, calculated as titanium atoms per liter of total liquid volume.

[0035] Examples of catalysts containing a compound having a transition metal atom of Group 4 of the periodic table include solid titanium trichloride catalysts described in JP-A-54-107989 and the like; magnesium-supported titanium catalysts described in JP-A-57-63310, JP-A-58-83006, JP-A-3-706, JP-A-3476793, JP-A-4-218508, JP-A-2003-105022 and the like; metallocene catalysts described in WO 2014 / 050817, WO 01 / 53369, WO 01 / 27124, JP-A-3-193796, JP-A-02-41303 and the like; carrier-supported metallocene catalysts described in JP-A-2009-144148 and JP-A-2022-37931; and non-patent documents such as Polyolefins Journal, Vol. 4, No. 1, pp. 123-136 (2017), or the non-patent document Macromolecules, Vol. 40, pp. 4130-4137 (2007), so-called postmetallocene catalysts having titanium atoms or hafnium atoms are preferably used.

[0036] The catalyst may be one produced by referring to the above-mentioned known literature, or may be a commercially available product. Commercially available solid titanium trichloride catalysts include, for example, "Solvay Catalyst CATA-1" manufactured by Tosoh Finechem Corporation. Commercially available magnesium-supported titanium catalysts include, for example, "THC Series" manufactured by Toho Titanium Co., Ltd. and "PolyMax Series" manufactured by Clariant. Commercially available metallocene catalysts include, for example, "rac-Dimethylsilylbis(1-indenyl)zirconium dichlorid" manufactured by Strem.

[0037] (cocatalyst component) In the above polymerization reaction, it is preferable to use a co-catalyst. The cocatalyst component is preferably an organometallic compound catalyst component, and specifically, an organoaluminum compound or a hydrolyzed polymer thereof can be mentioned. The organoaluminum compound is, for example, R a n AlX 3-nIt is shown as follows.

[0038] R a n AlX 3-n R in a is preferably a hydrocarbon group having 1 to 12 carbon atoms, such as an alkyl group, a cycloalkyl group, or an aryl group. Specific examples of hydrocarbon groups having 1 to 12 carbon atoms include methyl, ethyl, n-propyl, isopropyl, isobutyl, pentyl, hexyl, octyl, cyclopentyl, cyclohexyl, phenyl, and tolyl groups. R a n AlX 3-n In the formula (I), X is preferably a halogen atom or a hydrogen atom, and n is preferably an integer of 1 to 3.

[0039] R a n AlX 3-n Specific examples of the organoaluminum compound represented by the formula (I) include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, and tri-2-ethylhexylaluminum; alkenylaluminums such as isoprenylaluminum; dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, diisopropylaluminum chloride, diisobutylaluminum chloride, and dimethylaluminum bromide; alkylaluminum sesquihalides such as methylaluminum sesquichloride, ethylaluminum sesquichloride, isopropylaluminum sesquichloride, butylaluminum sesquichloride, and ethylaluminum sesquibromide; alkylaluminum dihalides such as methylaluminum dichloride, ethylaluminum dichloride, isopropylaluminum dichloride, and ethylaluminum dibromide; and alkylaluminum hydrides such as diethylaluminum hydride and diisobutylaluminum hydride. Of the above specific examples, trialkylaluminums such as triethylaluminum and triisobutylaluminum are preferred.

[0040] For example, when the catalyst containing a compound having a Group 4 transition metal atom of the periodic table is a magnesium-supported titanium catalyst component, the amount of the cocatalyst component added may be such that typically 0.1 to 10,000 g, and preferably 1 to 5,000 g, of polymer is produced per gram of the magnesium-supported titanium catalyst component, and the amount is typically 0.1 to 1,000 mol, preferably 0.5 to 500 mol, and more preferably 1 to 200 mol per mole of titanium atom in the magnesium-supported titanium catalyst component.

[0041] [Polymerization reaction] The polymerization reaction can be carried out by a liquid phase polymerization method such as solution polymerization, suspension polymerization (slurry polymerization), or bulk polymerization, a gas phase polymerization method, or any other known polymerization method. The polymerization reaction is preferably carried out by a suspension polymerization method.

[0042] [solvent] When the polymerization reaction is carried out by a liquid phase polymerization method, a solvent may not be used, or an inert hydrocarbon may be used as the solvent. Examples of the inert hydrocarbon solvent include saturated hydrocarbons such as pentane, cyclopentane, hexane, cyclohexane, heptane, isoheptane, and isooctane; and aromatic hydrocarbons such as benzene and toluene. The solvent may be used alone or in combination of two or more kinds.

[0043] [Polymerization conditions] (Polymerization method) The polymerization reaction can be carried out in any of batch, semi-continuous and continuous systems. The polymerization reaction can also be carried out in two or more stages by changing the reaction conditions. (Polymerization temperature) The polymerization temperature in the above polymerization reaction is usually 10 to 150° C., and preferably 30 to 120° C. If the polymerization temperature is within the above range, the progress of the polymerization reaction can be promoted while maintaining good catalytic activity, resulting in good productivity. (polymerization pressure) The polymerization pressure in the polymerization reaction is usually from normal pressure to 5 MPaG, preferably from 0.05 to 4 MPaG. If the polymerization pressure is within the above range, there is no need for devices such as a high-pressure-resistant reactor or an exhaust pump, which is economically advantageous. (Polymerization time) The polymerization time in the polymerization reaction is usually 0.1 to 10 hours, and preferably 0.5 to 5 hours. If the polymerization time is within the above range, deterioration of the physical properties of the polymer due to thermal degradation is suppressed, and it is easy to produce a polymer with good physical properties. (termination of polymerization) The polymerization reaction may be terminated by removing the monomer by distillation or filtration, or by adding any polymerization terminator as needed. The polymerization terminator is preferably a compound that reacts with a catalyst, including a compound having a transition metal atom of Group 4 of the periodic table. Examples of the polymerization terminator include compounds having an active proton, such as water, alcohols, primary amines, secondary amines, thiols, and Brestedt's acid, as well as ethers, phosphines, tertiary amines, thioethers, carbon dioxide, and oxygen molecules. The polymerization terminator may be used alone or in combination of two or more kinds.

[0044] [Additives] If necessary, additives may be added to the polymerization reaction system, such as silane compounds such as methyl(cyclohexyl)dimethoxysilane, ester compounds such as ethyl benzoate, ether compounds such as 2,2-alkyl-substituted-1,3-dimethoxypropane, and amine compounds such as 2,2,6,6-tetramethylpiperidine. The additives may be used alone or in combination of two or more.

[0045] [Removal of catalyst components] After the polymerization reaction, it is preferable to carry out a step of removing catalyst components contained in the 3-methyl-1-butene copolymer and the copolymer resin used in the copolymer composition. The method for removing the catalyst components is not particularly limited and can be a known method. For example, there is a method in which an alcohol such as isobutanol or 2-propanol is added to the crude 3-methyl-1-butene copolymer and crude copolymer resin obtained by the polymerization reaction, the mixture is stirred at a temperature of about 10 to 100°C, and the 3-methyl-1-butene copolymer and copolymer resin are separated. There is also a method in which an alcohol such as isobutanol or 2-propanol and a mineral acid such as hydrochloric acid or nitric acid are added to the crude 3-methyl-1-butene copolymer and crude copolymer resin obtained by the polymerization reaction, the mixture is stirred at a temperature of about 10 to 100°C, and the 3-methyl-1-butene copolymer and copolymer resin are separated. The catalyst component removal operation may be carried out on the polymer slurry immediately after the polymerization reaction, or may be carried out after removing unreacted monomers and the reaction solvent from the polymer slurry by distillation or filtration, or may be carried out after carrying out the soluble component removal operation described below.

[0046] [Removal of soluble components] The crude 3-methyl-1-butene copolymer and crude copolymer resin after the above-described polymerization reaction may contain polymerization components (hereinafter referred to as "soluble components") that are soluble in a heated hydrocarbon solvent (a hydrocarbon compound having 4 to 20 carbon atoms, which may have a branched or cyclic structure). Details of the soluble components are unclear, but possible soluble components include oligomer components of the 3-methyl-1-butene copolymer resin, polymer components with low stereoregularity, and polymer components with a low content of structural units derived from 3-methyl-1-butene. Therefore, when soluble components are contained in the crude 3-methyl-1-butene copolymer, the method for producing the 3-methyl-1-butene copolymer of this embodiment may include a step of removing the soluble components, or the copolymer may be used directly for various applications without removing the soluble components. The method for removing the soluble components is not particularly limited and may be any known method. Examples of the soluble component removal procedure include adding a hydrocarbon solvent such as heptane to the crude 3-methyl-1-butene copolymer and crude copolymer resin obtained, stirring the mixture at a temperature of about 50 to 100°C, and then filtering the solution. Furthermore, since the soluble components dissolve in unreacted monomers as well as in the hydrocarbon solvent, they can also be removed by stirring the polymer slurry obtained by the polymerization reaction described above at a temperature of about 50 to 100°C and then filtering the solution. These removal procedures may be repeated. The removal of the soluble components may be carried out on the polymer slurry immediately after the polymerization reaction, or may be carried out after the unreacted monomers and reaction solvent have been removed from the polymer slurry by distillation or filtration.

[0047] [Drying of 3-methyl-1-butene copolymers and copolymer resins] In the method for producing the 3-methyl-1-butene copolymer of this embodiment, after the above-mentioned first and second steps and various steps performed as needed, a step of drying the obtained 3-methyl-1-butene copolymer may be performed. Similarly, with regard to the copolymer resin used in the copolymer composition, after the above-mentioned polymerization reaction and various steps performed as needed, the copolymer resin may be dried. The drying is not particularly limited and may be performed by a known method. For example, drying may be performed by removing volatile components under conditions of normal pressure to 1 mmHg and 20 to 200°C. During drying, the 3-methyl-1-butene copolymer and copolymer resin may be left stationary, or may be fluidized by blowing air or an inert gas, or may be fluidized by a mechanical method such as using an agitating rotary blade dryer, a rotary dryer, a continuous tray dryer, or a fluidized dryer.

[0048] <Resin composition> The resin composition of the present embodiment contains at least one selected from the group consisting of the above-mentioned 3-methyl-1-butene copolymer and 3-methyl-1-butene copolymer composition. The resin composition may contain additives such as alkyl radical scavengers, antioxidants, antacids, light stabilizers, antistatic agents, flame retardants, pigments, polymerization inhibitors, heavy metal deactivators, ultraviolet absorbers, nucleating agents, clarifying agents, lubricants, fluorescent brighteners, and rust inhibitors as optional components, as long as the effects of the present invention are not impaired. The optional components may be used alone or in combination of two or more.

[0049] [Alkyl radical scavengers] The term "alkyl radical scavenger" refers to a compound that reacts with an alkyl radical derived from a 3-methyl-1-butene copolymer or copolymer composition and then stabilizes the radical, thereby suppressing a chain reaction of main chain scission initiated by the alkyl radical. The alkyl radical scavenger preferably contains at least one selected from the group consisting of an acrylphenol compound and a benzofuranone compound. The alkyl radical scavengers may be used alone or in combination of two or more.

[0050] <Acrylphenol compounds> The acrylic phenol compound used as the alkyl radical scavenger can be represented, for example, by the following general formula (I).

[0051] [ka]

[0052] In general formula (I), R 1 represents a hydrogen atom or a methyl group, and R 2 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R 3 ,R 4 ,R 5 and R 6 each independently represents an alkyl group having 1 to 9 carbon atoms. Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. The alkyl group having 1 to 9 carbon atoms may be linear or branched. Examples of the alkyl group having 1 to 9 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, a 2,2-dimethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-nonyl group. R 1 is preferably a hydrogen atom. R 2 is preferably a hydrogen atom or a methyl group, more preferably a methyl group. R 3 ,R 4 ,R 5 and R 6 are each independently preferably an alkyl group having 3 to 8 carbon atoms, more preferably an alkyl group having 5 carbon atoms, and even more preferably a 1,1-dimethylpropyl group.

[0053] Examples of the acrylic phenol compound represented by general formula (I) include 2,4-di-t-amyl-6-[1-(3,5-di-t-amyl-2-hydroxyphenyl)ethyl]phenyl acrylate, 2,4-di-t-butyl-6-[1-(3,5-di-t-butyl-2-hydroxyphenyl)ethyl]phenyl acrylate, and 2-t-butyl-6-[(3-t-butyl-2-hydroxy-5-methylphenyl)methyl]-4-methylphenyl acrylate. Commercially available alkyl radical scavengers may be used, and examples of the acrylic phenol compound represented by general formula (I) include products under the trade names "Sumilizer (registered trademark) GS" and "Sumilizer (registered trademark) GM" manufactured by Sumitomo Chemical Co., Ltd.

[0054] <Benzofurano compounds> The benzofuranone compound used as the alkyl radical scavenger can be represented, for example, by the following general formula (II):

[0055] [ka]

[0056] In general formula (II), R 7 and R 8 each independently represents an alkyl group having 1 to 4 carbon atoms, and R 9 and R 10 each independently represents an alkyl group having 1 to 9 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, and a t-butyl group. The alkyl group having 1 to 9 carbon atoms may be linear or branched. Examples of the alkyl group having 1 to 9 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, a 2,2-dimethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-nonyl group. R 7 and R 8 are each independently preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. R 9 and R 10 are each independently preferably an alkyl group having 1 to 4 carbon atoms, more preferably a t-butyl group.

[0057] Examples of the benzofuranone compound represented by general formula (II) include 5,7-di-t-butyl-3-(3,4-di-methyl-phenyl)-3H-benzofuran-2-one, 5,7-di-t-butyl-3-(3,4-di-propyl-phenyl)-3H-benzofuran-2-one, and 4-t-butyl-2-(5-t-butyl-2-oxo-3H-benzofuran-3-yl)phenyl-3,5-di-t-butyl-4-hydroxybenzoate. Commercially available alkyl radical scavengers may be used, and examples of the benzofuranone compound represented by general formula (II) include "Irganox (registered trademark) HP-136" manufactured by BASF and "Revonox (registered trademark) 501" manufactured by Chitec.

[0058] <Blend amount> The amount of the alkyl radical scavenger to be blended relative to 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is preferably 0.01 to 1.00 parts by mass. When the amount of the alkyl radical scavenger is within the above range, the stability of physical properties can be maintained during melt kneading. Furthermore, there is no risk of the alkyl radical scavenger bleeding out or deterioration of moisture absorption, which would impair the physical properties required of the resin composition. Furthermore, there is no risk of decomposition gas being generated during melt molding, which would result in molding defects.

[0059] From the viewpoint of more easily exerting the effect of the alkyl radical scavenger, the amount of the alkyl radical scavenger blended per 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is more preferably 0.02 parts by mass or more, and even more preferably 0.05 parts by mass or more. In addition, from the viewpoint of balancing the effect of the alkyl radical scavenger with economic efficiency, the amount of the alkyl radical scavenger to be blended per 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is more preferably 0.80 parts by mass or less, and even more preferably 0.70 parts by mass or less. When two or more alkyl radical scavengers are blended, the amount of the alkyl radical scavengers blended refers to the total amount of the alkyl radical scavengers blended.

[0060] [Antioxidants] From the viewpoint of heat aging resistance, in the melt-kneading step, at least one antioxidant selected from the group consisting of phenol-based antioxidants and phosphorus-based antioxidants may be further blended and melt-kneaded, or in the melt-kneading step, melt-kneading may be performed without blending any antioxidant. The antioxidants may be used alone or in combination of two or more.

[0061] <Phenol-based antioxidant> Examples of phenolic antioxidants include pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-tris[(4-t-butyl-3-hydroxy-2,6-xylyl)methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and octaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]. Decyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, thiodiethylene-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionamide], 3,3',3'',5,5',5''-hexa-t-butyl-a,a',a''-(mesitylene-2,4,6-triyl)tri-p-cresol, ethylene bis (Oxyethylene)bis[3-(5-t-butyl-4-hydroxy-m-tolyl)propionate], hexamethylene-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,6-di-t-butyl-4-[4,6-bis(octylthio)-1,3,5-triazin-2-ylamino]phenol, 3,9-bis[2-(3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy)-1,1-dimethylethyl]-2, Examples include 4,8,10-tetraoxaspiro(5,5)undecane, 4,4',4''-(1-methylpropanyl-3-ylidene)tris(6-t-butyl-m-cresol), 6,6'-di-t-butyl-4,4'-butylidene-di-m-cresol, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, and benzenepropionic acid 3,5-bis-(1,1-dimethylethyl)-4-hydroxy-C7-C9 branched alkyl ester.

[0062] As the phenolic antioxidant, commercially available products may be used, such as "ADEKA STAB (registered trademark) AO series" manufactured by ADEKA Corporation and "Irganox (registered trademark) series" manufactured by BASF Japan Ltd.

[0063] <Phosphorus-based antioxidant> Examples of the phosphorus-based antioxidant include 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, tetrakis(2,4-di-t-butylphenyl)-4,4'-biphenylenephosphonite, 2,2-methylenebis(4,6-di-t-butylphenyl)octylphosphite, and tris(2,4-di-t-butylphenyl)phosphite. phosphate, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, di-t-butyl-m-cresyl phosphonite, diethyl[(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)methyl]phosphonate, tris(2,4-di-t-butylphenyl)phosphite, tetrakis(2,4-di-t-butylphenyl)-4,4'-biphenylene diphosphonite, 3,9-bis(octadecyoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, tris(2,4-di-t-butylphenyl)phosphite, tris(nonylphenyl)phosphite, tetra-C12-15-alkyl Examples include [propane-2,2-diylbis(4,1-phenylene)]bis(phosphite), 2-ethylhexyldiphenyl phosphite, isodecyldiphenyl phosphite, trisisodecyl phosphite, triphenyl phosphite, and 3,9-bis[2,4-bis(1-methyl-1-phenylethyl)phenoxy]-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane.

[0064] As the phosphorus-based antioxidant, commercially available products may be used, and examples thereof include "ADK STAB (registered trademark) PEP series" and "ADK STAB (registered trademark) HP series" manufactured by ADEKA Corporation, "Irgafos (registered trademark) series" manufactured by BASF Japan Ltd., and "HOSTANOX (registered trademark) P-EPQ" manufactured by Clariant.

[0065] <Other antioxidants> In the melt-kneading step, antioxidants other than the phenol-based antioxidant and the phosphorus-based antioxidant may be added as long as the effects of the present invention are not impaired. Examples of antioxidants other than the phenol-based antioxidant and the phosphorus-based antioxidant include sulfur-based antioxidants and amine-based antioxidants.

[0066] <Blend amount> From the viewpoint of more easily exhibiting heat aging resistance, the amount of antioxidant blended per 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is preferably 0.01 part by mass or more, more preferably 0.10 part by mass or more. From the viewpoint of economy, the blending amount of the antioxidant per 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is preferably 1.00 part by mass or less, more preferably 0.80 part by mass or less. That is, the amount of the antioxidant to be blended per 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition is preferably 0.01 to 1.00 parts by mass. When two or more antioxidants are blended, the blending amount of the antioxidants refers to the total blending amount of the antioxidants.

[0067] <Antacids> From the viewpoint of suppressing deterioration due to acid components generated from residual metals and the like, it is preferable to further add an antacid in the melt-kneading step. Antacids include barium laurate, calcium stearate, zinc stearate, magnesium stearate, aluminum stearate, zinc oleate, and magnesium 12-hydroxystearate. The antacids may be used alone or in combination of two or more.

[0068] The amount of the antacid to be blended relative to 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition can be determined appropriately depending on the intended use, and may be, for example, 0.01 to 200 parts by mass.

[0069] <Filler> Depending on the intended use of the 3-methyl-1-butene copolymer or copolymer composition, a filler may be further blended and melt-kneaded in the melt-kneading step, or a filler may be blended into the resin composition and then melt-kneaded again. Examples of fillers include fibrous compounds such as glass fiber, alumina fiber, resin fiber, carbon fiber, and cellulose fiber; plate-like compounds such as mica, talc, montmorillonite, and plate-like aluminum; spherical compounds such as glass beads, shirasu balloons, and acrylic balloons; needle-like compounds such as acicular metal titanate, wollastonite, acicular silica, and tin oxide; and powdered compounds such as powdered metal titanate, finely divided wood chips, titanium oxide, calcium carbonate, silica, and alumina. These fillers may be surface-treated with, for example, a silane coupling agent. A compatibilizer may also be used to enhance the dispersibility of the filler. The fillers may be used alone or in combination of two or more.

[0070] The amount of filler to be blended relative to 100 parts by mass of the 3-methyl-1-butene copolymer or copolymer composition can be determined appropriately depending on the application, and may be, for example, 0.01 to 300 parts by mass.

[0071] [Melting and kneading conditions] <Inert atmosphere> Depending on the application of the 3-methyl-1-butene copolymer or copolymer composition, in the melt-kneading step, an inert gas is injected into the melt-kneader, or the inside of the melt-kneader is degassed under reduced pressure. In order to prevent deterioration of the physical properties of the melt-kneaded 3-methyl-1-butene copolymer or copolymer composition due to oxygen and to maintain good mechanical properties, it is preferable to melt-knead the copolymer or copolymer composition in an inert atmosphere or in a low-oxygen state. Here, in this specification, a "low-oxygen state" refers to a state in which the oxygen concentration inside the melt kneader is lowered compared to before the degassing under reduced pressure. In the "low-oxygen state," the oxygen concentration inside the melt kneader is preferably 5% or less, more preferably 2% or less, and even more preferably 1% or less. The oxygen concentration is measured using an oxygen concentration meter such as a diaphragm-type galvanic type.

[0072] The method of melt-kneading by injecting an inert gas into the melt-kneader may involve, for example, introducing each component into the melt-kneader while injecting the inert gas into the melt-kneader, or introducing each component into the melt-kneader and then injecting the inert gas into the melt-kneader. Furthermore, the inert gas may be continuously injected into the melt-kneader during melt-kneading. The inert gas may be injected in a manner that is appropriate for the equipment provided in each melt kneader. For example, the inert gas may be injected from a supply section for a gas such as an inert gas provided in the melt kneader, from a supply section for each component provided in the melt kneader, or from a gas vent provided in the melt kneader. There is no limitation on the injection method as long as the inert gas can be injected into the entire area from the inert gas supply section to the heating section where melting and kneading is performed, and melting and kneading can be performed. Examples of inert gases include nitrogen gas, helium gas, neon gas, argon gas, krypton gas, and carbon dioxide gas, with nitrogen gas being preferred from the viewpoints of availability and versatility.

[0073] The method of melt-kneading by degassing the inside of the melt-kneader under reduced pressure may be, for example, to carry out melt-kneading by charging each component into the melt-kneader and then degassing the inside of the melt-kneader under reduced pressure. During melt-kneading, degassing the inside of the melt-kneader under reduced pressure may be carried out intermittently or continuously. The method of degassing the inside of the melt kneader under reduced pressure can be carried out depending on the equipment provided in each melt kneader, and may be carried out through a vacuum vent, for example. There are no limitations on the vacuum degassing method for the inside of the melt kneader, as long as it is possible to perform melt kneading under a low-oxygen condition. When degassing under reduced pressure, the inside of the melt kneader can be in a vacuum state of, for example, 50 kPa or less and 0.1 kPa or more.

[0074] The melt kneader may be a single-screw extruder, a multi-screw extruder, a kneader, a Banbury mixer, or the like, which is equipped with equipment capable of melt-kneading by injecting an inert gas into the interior of the melt kneader, or equipment capable of melt-kneading by degassing the interior of the melt kneader under reduced pressure.

[0075] <Temperature, time, etc.> In the melt-kneading step, the melt-kneading is preferably carried out at 300 to 380°C depending on the application of the 3-methyl-1-butene copolymer or copolymer composition. If the melt-kneading temperature is 300°C or higher, the 3-methyl-1-butene copolymer or copolymer composition melts, resulting in good dispersion of the alkyl radical scavenger and additives.If the melt-kneading temperature is 380°C or lower, decomposition of raw materials such as the 3-methyl-1-butene copolymer or copolymer composition and the alkyl radical scavenger can be suppressed. From the viewpoint of sufficiently dispersing the alkyl radical scavenger and additives throughout the 3-methyl-1-butene copolymer or copolymer composition, the melt-kneading temperature is more preferably 310°C or higher. In addition, from the viewpoint of preventing the raw materials from being significantly decomposed, the melt-kneading temperature is more preferably 380°C or lower, and even more preferably 360°C or lower.

[0076] The melt-kneading time can be adjusted depending on the size of the kneading apparatus, etc. For example, it may be 1 to 15 minutes, but is not limited to this numerical range of the melt-kneading time. In this embodiment, the "melt-kneading time" refers to the time during which the mixer is rotating in a batch kneader, and refers to the residence time of the raw materials in the apparatus in the case of a continuous extrusion kneader.

[0077] The rotation speed of the mixer during melt-kneading may be 80 rpm or more, or 100 rpm or more, and may be 400 rpm or less, or 350 rpm or less. After the melt-kneading, the melt-kneaded 3-methyl-1-butene copolymer, 3-methyl-1-butene copolymer composition or resin composition is taken out of the melt-kneader and cooled. [Example]

[0078] The present invention will be specifically explained below with reference to examples and comparative examples, but the present invention is not limited to these.

[0079] In the examples and comparative examples, measurements or evaluations were carried out by the following methods. [Melt viscosity] 100 parts by mass of the 3-methyl-1-butene copolymer resin of the first step in Example 1 and the 3-methyl-1-butene copolymer obtained in the examples and comparative examples were mixed with 0.2 parts by mass of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], trade name "AO-60", manufactured by ADEKA Corporation, 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetrakis ...hydroxyphenyl)propionate, and 0.2 parts by mass of 3-methyl-1-butene copolymer obtained in the first step in Example 1 and the 3-methyl-1-butene copolymer obtained in the examples and comparative examples. 0.2 parts by mass of hexa-3,9-diphosphaspiro[5.5]undecane, trade name "PEP-36" manufactured by ADEKA Corporation, 0.1 parts by mass of 2,4-di-t-amyl-6-[1-(3,5-di-t-amyl-2-hydroxyphenyl)ethyl]phenyl acrylate, trade name "Sumilizer GS" manufactured by Sumitomo Chemical Co., Ltd., and 0.25 parts by mass of zinc stearate were dry blended, and the mixture was subjected to a capillary rheometer ("Capillography 1C" manufactured by Toyo Seiki Seisakusho Co., Ltd.) at a barrel temperature of 320°C and a shear rate of 1216 sec -1The melt viscosity (Pa·s) was measured under the following conditions: (capillary: inner diameter 1.0 mm × length 10 mm, extrusion speed 10 mm / min).

[0080] [Melting point] The 3-methyl-1-butene copolymers obtained in the examples and comparative examples were heated from 30°C to 320°C at a rate of 10°C / min under a nitrogen flow rate (100 mL / min) using a differential scanning calorimeter (TA Instrument "DSC25"), held at 320°C for 5 minutes, and then cooled to -70°C at a rate of 10°C / min. The melting points were evaluated when the copolymers were held at -70°C for 5 minutes and then heated to 320°C at a rate of 10°C / min.

[0081] [Breaking elongation, yield strength] (1) Preparation of test specimens To 100 parts by mass of the 3-methyl-1-butene copolymer obtained in the examples and comparative examples, 0.2 parts by mass of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], trade name "AO-60", manufactured by ADEKA Corporation, 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, trade name "PEP- 0.2 parts by mass of "36" manufactured by ADEKA Corporation, 0.1 parts by mass of 2,4-di-t-amyl-6-[1-(3,5-di-t-amyl-2-hydroxyphenyl)ethyl]phenyl acrylate, trade name "Sumilizer GS" manufactured by Sumitomo Chemical Co., Ltd., and 0.25 parts by mass of zinc stearate were dry blended and melt-kneaded using a small kneader ("Micro15 Compounder" manufactured by DSMXplore) under conditions of 50 rpm and 320°C in a nitrogen atmosphere. After melt-kneading for 2 minutes, a small test piece (1BA type dumbbell test piece as specified in JIS7161-2 Appendix A) was molded using a small injection molding machine ("Micro Injection Molding Machine 10cc" manufactured by DSMXplore) attached to the small kneader under the conditions of an injection pressure of 0.3 MPa, a retention time in the mold of 35 seconds, and a mold temperature of 180°C. (2) Measurement The prepared dumbbell test pieces were stored at 23°C and 49% humidity for at least 24 hours, and then the breaking elongation X (%) and yield strength Y (MPa) were measured at 23°C, 49% humidity, and a tensile speed of 5 mm / min using a universal testing machine (Instron Corporation, "INSTRON5900R-5666") in accordance with JIS K 7161-1:2014. The measurements were performed five times, and the average values ​​were used.

[0082] [Content of structural units derived from comonomers] The content ratio of structural units derived from α-olefins (comonomers) other than 3-methyl-1-butene in the 3-methyl-1-butene copolymers obtained in the examples and comparative examples was determined by IR measurement using an FT-IR analyzer (manufactured by Ailent Technologies, device name "cary 600 series FTIR spectrometer") by the ATR method, as follows: Bending vibration of 3-methyl-1-butene homopolymer originating from the main chain methylene group 1,461 cm -1 and the bending vibration of 727 cm originating from the side chain methylene group of the α-olefin homopolymer. -1 A calibration curve was created from the ratio of the peak area of ​​the α-olefins other than 3-methyl-1-butene to the peak area of ​​the α-olefins added, and the ratio of the peak area of ​​the α-olefins added was calculated. The IR measurements were carried out on the 3-methyl-1-butene copolymers obtained in the examples and comparative examples, and the obtained measured values ​​were inserted into the calibration curve to determine the content of structural units derived from α-olefins other than 3-methyl-1-butene.

[0083] Preparation of Titanium Catalyst Component [Manufacturing Example 1] 47.6 g (500 mmol) of anhydrous magnesium chloride, 250 mL of decane, and 234 mL (1.5 mol) of 2-ethylhexyl alcohol were heated at 130°C for 2 hours to form a homogeneous solution. The homogeneous solution thus obtained was cooled to room temperature and then added dropwise over 1 hour to 2 L (18 mol) of titanium tetrachloride maintained at -20°C. After the addition, the temperature of the mixture was raised to 110°C over 2 hours. Upon reaching 110°C, 42.4 mL (160 mmol) of dibutyl phthalate was added and the mixture was maintained at the same temperature with stirring for another 2 hours. After the 2-hour reaction, the mixture was allowed to stand and the supernatant was removed. Decane and hexane were added, and the solid components were washed three times. They were then resuspended in 2 L of titanium tetrachloride and heated again at 110°C for 2 hours. After the reaction was complete, the mixture was again left to stand using decane and hexane, and the supernatant was repeatedly removed. The mixture was thoroughly washed until no free titanium compounds were detected in the washings. The resulting suspension was dried under reduced pressure at room temperature for 6 hours to obtain a dried titanium catalyst component. The composition of the titanium catalyst component thus obtained was 4.0 mass% titanium atoms, 56.0 mass% chlorine atoms, 17.0 mass% magnesium atoms, and 11.0 mass% ethyl benzoate.

[0084] <Synthesis of 3-methyl-1-butene copolymer> [Example 1] A 20 L stainless steel autoclave was charged with 8.0 kg of 3-methyl-1-butene, 0.6 kg of 1-decene, 50 g of triethylaluminum diluted with hexane to a concentration of 1 mol / L, and 4 g of the titanium catalyst component produced in Production Example 1. The polymerization reaction was carried out for 2 hours at 70 °C while continuously supplying hydrogen at a rate of 10 mL / min. At this stage, a portion of the polymerization slurry was withdrawn, and the viscosity of the copolymer resin, excluding the solvent-soluble polymer produced at this stage, was measured; the melt viscosity was 152 Pa s. The hydrogen flow rate was then changed to 40 mL / min, and polymerization continued. After changing the hydrogen flow rate, 200 g of isoamyl alcohol was injected two hours later to stop the reaction and remove excess unreacted monomer. 2 kg of normal heptane was then introduced, and the mixture was stirred at 60°C for 30 minutes. The solids were then filtered off using a pressure filter. This procedure was repeated twice, and then the solvent was changed from 2 kg of normal heptane to 3 kg of 2-propanol, and the same procedure was repeated twice. 7.7 kg of the crude 3-methyl-1-butene copolymer obtained during this procedure was placed in a 50 L vessel equipped with a stirrer. 8 kg of 1 mol / L hydrochloric acid and 16 kg of 2-propanol were then added and stirred for 1 hour. The suspension was filtered using vacuum filtration and washed with 10 kg of 2-propanol. The crude 3-methyl-1-butene copolymer was placed in a 50 L vessel equipped with a stirrer. 20 kg of 2-propanol was then added and stirred for 1 hour. The suspension was filtered by vacuum filtration and washed with 10 kg of 2-propanol. The washed 3-methyl-1-butene copolymer was dried under reduced pressure at 80°C for 2 days to obtain 3.2 kg of 3-methyl-1-butene copolymer. The melting point of the resulting 3-methyl-1-butene copolymer was 286.7°C and the melt viscosity was 133 Pa·s. The content of structural units derived from the comonomer 1-decene was 0.8 mol%. The elongation at break and yield strength were measured using the same methods as above. The results are shown in Table 1. The unit of hydrogen flow rate "mL / min" in the first and second steps was converted to the hydrogen flow rate per unit volume "mL / (h L)" based on the initial charged volume of 3-methyl-1-butene based on the following formula (A), and the converted values ​​are shown in Table 1. The same applies to Comparative Examples 1 and 2. b=a×60 / V0 Formula (A) In the above formula (A), a represents the hydrogen flow rate (mL / min), V0 represents the initial charged volume of 3-methyl-1-butene (L), and b represents the hydrogen flow rate per unit volume (mL / (h·L)).

[0085] [Comparative Example 1] A 3-methyl-1-butene copolymer was synthesized in the same manner as in Example 1, except that hydrogen was continuously supplied at a flow rate of 40 mL / min for 4 hours. The melting point of the resulting 3-methyl-1-butene copolymer was 290.1°C and the melt viscosity was 74 Pa·s. The content of structural units derived from the comonomer 1-decene was 0.5 mol%. The elongation at break and yield strength were measured using the same methods as above. The results are shown in Table 1.

[0086] Comparative Example 2 A 3-methyl-1-butene copolymer was synthesized in the same manner as in Example 1, except that hydrogen was continuously supplied at a flow rate of 20 mL / min for 4 hours. The melting point of the resulting 3-methyl-1-butene copolymer was 289.4°C and the melt viscosity was 56 Pa·s. The content of structural units derived from the comonomer 1-decene was 0.6 mol%. The elongation at break and yield strength were measured using the same methods as above. The results are shown in Table 1.

[0087] [Table 1]

[0088] It can be seen from Table 1 that the 3-methyl-1-butene copolymers obtained in the examples have significantly lower melting points, satisfy the formula (1) Y > (-X / 16) + 42.5, and have an excellent balance between breaking elongation and yield strength. This shows that the 3-methyl-1-butene copolymer of the present embodiment has excellent heat resistance, can suppress thermal degradation during processing, and achieves both toughness and strength.

Claims

[Claim 1] a first step of polymerizing 3-methyl-1-butene by continuously supplying hydrogen at a hydrogen flow rate per unit volume of 1 to 65 mL / (h·L) based on the initial charged volume of the 3-methyl-1-butene; a second step of polymerizing the 3-methyl-1-butene by continuously supplying hydrogen at a hydrogen flow rate per unit volume of 65 to 500 mL / (h L) based on the initial charged volume of the 3-methyl-1-butene used in the first step; A method for producing a 3-methyl-1-butene copolymer, wherein the hydrogen flow rate in the first step is different from the hydrogen flow rate in the second step.

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