Method for producing modified polyolefin

Abstract

To provide a production method for producing a polyolefin modified body, capable of introducing an isocyanate group to a polyolefin, in a short step and in an industrially advantageous condition.SOLUTION: There is provided a production method for producing a polyolefin modified body including, a step for addition reaction of a polyolefin whose carbon-carbon double bond terminal ratio is 20% or greater, and a compound expressed by a general formula I: the polyolefin modified body has at least one isoxazoline skeleton and at least one isocyanate group; in any order, the double bond of the polyolefin and at least one nitrile oxide group of the compound is subjected to addition reaction; and at least one nitrile oxide group in the compound is converted into the isocyanate group.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing a modified polyolefin. [Background technology]

[0002] Polyolefins such as polyethylene and polypropylene have excellent moldability and mechanical properties, and are therefore used in a wide range of fields, including industrial applications and daily necessities, as films, sheets, fibers, nonwoven fabrics, molded products (containers, etc.), and modifiers.

[0003] Polyolefins are known to have poor reactivity due to their saturated hydrocarbon backbone, making them difficult to modify. They are also known to have poor compatibility with other resins. One known method for solving these problems is to modify polyolefins using peroxides. However, this method causes a crosslinking reaction in polyethylene, while a side reaction in polypropylene occurs, resulting in a decrease in molecular weight due to molecular chain scission.

[0004] In recent years, attempts have been made to introduce polar functional groups into polyolefins that have a carbon-carbon double bond at one of the two ends of their main chains (Patent Document 1). Introducing a polar functional group into the terminal carbon-carbon double bond through a chemical reaction allows for the introduction of reactive sites into the polyolefin, improving its reactivity. In other words, reacting the introduced polar functional group with a different resin makes it possible to produce block copolymers, enabling adhesion and compatibility with other polymers.

[0005] It is known that compounds having an isocyanate group are widely used as crosslinking agents and modifiers in metal, woodworking, automobile repair paints, etc. (Patent Documents 2 and 3). Compounds having an isocyanate group are useful as reactants in a variety of applications because they readily undergo addition reactions with active hydrogen compounds such as amine groups and hydroxyl groups due to the resonance structure of the isocyanate group. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2019 / 107450 [Patent Document 2] Japanese Patent Publication No. 2020-62821 [Patent Document 3] Patent Publication No. 2021-75717 Summary of the Invention [Problem to be solved by the invention]

[0007] Methods for introducing isocyanate groups into polyolefins include the use of peroxides and reactions in solvents, but these techniques are industrially disadvantageous because they require multiple steps and large amounts of solvent.

[0008] An object of the present invention is to provide a method for producing a modified polyolefin, which method is capable of introducing an isocyanate group into a polyolefin in a short number of steps under industrially advantageous conditions. [Means for solving the problem]

[0009] The present inventors have considered various aspects and conducted experimental searches to solve the above-mentioned problems, and have found that by using a polyolefin having a specific structure and a specific compound having a nitrile oxide group, an isocyanate group can be introduced into a polyolefin in a short process under industrially advantageous conditions, thereby completing the present invention. The present invention relates to the following [1] to [7].

[0010] [1] A method for producing a modified polyolefin, comprising subjecting a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more to an addition reaction with a compound represented by the following general formula [I], wherein the modified polyolefin has at least one isoxazoline skeleton and at least one isocyanate group: A production method comprising, in any order, a step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and a step of converting at least one nitrile oxide group of the compound to an isocyanate group. [ka] In the general formula [I], s is an integer of 2 to 4; R 1 and R 2 are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms; and X are each independently a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )-and;R 3 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; and A is an s-valent organic group. [2] A method for producing a modified polyolefin, comprising subjecting a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more to an addition reaction with a compound represented by the following general formula [I], wherein the modified polyolefin is represented by the following general formula [II]: A production method comprising, in any order, a step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and a step of converting at least one nitrile oxide group of the compound to an isocyanate group. [ka] [ka] In the general formulas [I] and [II], s is an integer of 2 to 4; n is an integer of 1 to 3; s>n; R 1 and R 2 are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms; and X are each independently a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )-and;R 3is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; A is an s-valent organic group; R 4 , R 5 and R 6 are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; R 7 is the backbone of the polyolefin. [3] The method for producing a modified polyolefin according to [1] or [2], wherein the step of converting at least one nitrile oxide group in the compound to an isocyanate group is carried out in the presence of an isomerization accelerator. [4] The method for producing a modified polyolefin according to any one of [1] to [3], wherein the polyolefin and the compound are subjected to an addition reaction in the substantial absence of a solvent. [5] The method for producing a modified polyolefin according to any one of [1] to [4], wherein the step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and the step of converting at least one nitrile oxide group of the compound to an isocyanate group are carried out in a single operation of melt-kneading a mixture of the polyolefin and the compound at 80 to 300°C. [6] The method for producing a modified polyolefin according to any one of [1] to [5], wherein the carbon-carbon double bond of the polyolefin is a vinyl group or a vinylidene group. [7] A modified polyolefin obtained by the production method according to any one of [1] to [6]. [Effects of the Invention]

[0011] According to the method for producing a modified polyolefin of the present invention, an isocyanate group can be introduced into a polyolefin in a short number of steps under industrially advantageous conditions. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a 1H-NMR spectrum of the modified polyolefin of Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0013] The following definitions of terms apply throughout the specification and claims. "Polyethylene" refers to an ethylene homopolymer or an ethylene-(α-olefin having 3 or more carbon atoms) copolymer containing more than 50 mol% of ethylene units. Polyethylene may contain 1 mol% or less of diene compound units. "Polypropylene" refers to a propylene homopolymer or a propylene-(ethylene or an α-olefin having 4 or more carbon atoms) copolymer containing 50 mol % or more propylene units. Polypropylene may contain 1 mol % or less of diene compound units. The term "1,3-dipole functional group" refers to a functional group that can undergo a 1,3-dipole cycloaddition reaction with an unsaturated bond (such as a carbon-carbon double bond, a carbon-carbon triple bond, or a carbon-nitrogen triple bond). "Backbone" refers to a linear molecular chain such that all molecular chains other than the backbone are considered pendants. The phrase "substantially free of solvent" means that no solvent is present other than that inevitably mixed in during the manufacturing process. The symbol "to" indicating a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0014] <Method of producing modified polyolefin> A method for producing a modified polyolefin includes addition-reacting a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more (hereinafter also referred to as "double-bond-containing polyolefin") with a compound represented by the following general formula [I], wherein the modified polyolefin has at least one isoxazoline skeleton and at least one isocyanate group, and the production method includes, in any order, a step of addition-reacting a double bond of the polyolefin with at least one nitrile oxide group of the compound, and a step of converting at least one nitrile oxide group of the compound to an isocyanate group. [ka] In the general formula [I], s is an integer of 2 to 4; R 1 and R 2 are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms; and X are each independently a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )-and;R 3 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; and A is an s-valent organic group.

[0015] [Double bond-containing polyolefin] The "polyolefin" in the double bond-containing polyolefin includes polyethylene, polypropylene, etc. The double bond-containing polyolefin may be used alone or in combination of two or more kinds. The polyethylene may contain more than 0 mol% and less than 50 mol% of an α-olefin other than ethylene as a comonomer. Also, the polyethylene may contain more than 0 mol% and 1 mol% or less of a diene compound as a comonomer. The content of diene as a comonomer is preferably 0 mol%. The polypropylene may contain more than 0 mol% and not more than 50 mol% of an α-olefin other than propylene as a comonomer. Also, the polypropylene may contain more than 0 mol% and not more than 1 mol% of a diene compound as a comonomer. The content of the diene as a comonomer is preferably 0 mol%. Examples of the α-olefin include ethylene, propylene, butene, hexene, octene, and 4-methyl-1-pentene. Examples of the diene compound include vinylnorbornene, dicyclopentadiene, ethylidenenorbornene, and 1,4-hexadiene.

[0016] From the viewpoint of reactivity, the rate of carbon-carbon double bond terminals in the double bond-containing polyolefin is 20% or more, preferably 40% or more, and more preferably 60 to 200%. The double bond-containing polyolefin may have a carbon-carbon double bond in the middle of the main chain, or may have a carbon-carbon double bond at the end or middle of the side chain. Here, the carbon-carbon double bond terminal percentage means the proportion of terminal carbon-carbon double bond groups present per molecular chain of a double bond-containing polyolefin. When all double bond-containing polyolefins have a carbon-carbon double bond group at only one end, the carbon-carbon double bond terminal percentage is 100%. The carbon-carbon double bond terminal percentage can take a value of 0 to 200%. Note that the calculation of the carbon-carbon double bond terminal percentage in a double bond-containing polyolefin does not include carbon-carbon double bonds at the ends of side chains.

[0017] As the carbon-carbon double bond, a vinyl group and a vinylidene group are preferred. As the carbon-carbon double bond, a vinyl group is preferred because of its excellent reactivity with the nitrile oxide group of the compound represented by general formula [I]. The nitrile oxide group, which is a 1,3-dipole functional group, is more reactive with sterically small olefinic bonds than with sterically large olefinic bonds.

[0018] When the double bond-containing polyolefin is a double bond-containing polypropylene, the polypropylene generally has the following terminal groups: Structures having a vinyl group at the terminal include structural formulas (1-a) and (1-f); Structures having a vinylidene group at the terminal include structural formula (1-b). [ka]

[0019] Furthermore, when the double bond-containing polyolefin is a double bond-containing polypropylene, the polypropylene may produce the following internal olefins in addition to regular monomer units within the polymer chain due to the reaction mechanism, and these may become monomer units constituting the polymer. [ka]

[0020] Double bond-containing polyolefins can generally be produced by coordination polymerization of α-olefins using a transition metal catalyst without the use of a chain transfer agent. Typically, molecular weight is controlled using a chain transfer agent during polyolefin production, resulting in a saturated terminal structure of the polyolefin. On the other hand, in coordination polymerization using a transition metal catalyst, if a chain transfer agent such as hydrogen or organoaluminum is not used, the polyolefin terminates as a carbon-carbon double bond. Terminal double bonds are particularly likely to form in polymerization systems in which molecular weight is controlled by the polymerization temperature. Furthermore, hydrogen generation can also lead to the formation of carbon-carbon double bonds in the main chain and in side chains. These details are described in Macromolecules, Vol. 38, 2005, pp. 6988-6996 and Topics in Catalysis, Vol. 7, 1999, pp. 145-163, among others.

[0021] Examples of transition metal catalysts include complex catalysts (Phillips catalysts, metallocene catalysts, post-metallocene catalysts, etc.) and Ziegler-Natta catalysts, with Phillips catalysts, metallocene catalysts, and post-metallocene catalysts being preferred, and metallocene catalysts and post-metallocene catalysts being particularly preferred due to their wide range of production possibilities. Furthermore, a small amount of a chain transfer agent may be added to the system, if necessary.

[0022] (Calculation method for carbon-carbon double bond terminal ratio) The carbon-carbon double bond terminal ratio means the ratio of molecular chains having a carbon-carbon double bond group at the end to the total polymer chains of the double bond-containing polyolefin. The carbon-carbon double bond terminal ratio can be calculated according to the method described in JP 2021-4376 A.

[0023] Specifically, the carbon-carbon double bond terminal ratio is calculated by the following formula. (Carbon-carbon double bond terminal rate) = (total number of carbon-carbon double bond terminals) / {((total number of terminals) - (number of LCBs)) ÷ 2} × 100 Here, the total number of carbon-carbon double bond terminals is 1The total number of carbon-carbon double bond ends per 1,000 monomer units is calculated by H-NMR. 1 H-NMR and 13 The LCB number is the total number of terminals per 1000 monomer units calculated by C-NMR. 13 This is the number of methine carbon atoms at the base of branched chains with 7 or more carbon atoms per 1,000 monomer units calculated by C-NMR.

[0024] The following is a description of double bond-containing polypropylene: 1 H-NMR and 13 This section explains how to identify the percentage of carbon-carbon double bond terminals using C-NMR.

[0025] 1. Sample preparation and measurement conditions 200 mg of sample was placed in an NMR sample tube with an inner diameter of 10 mm along with 2.4 ml of a mixed solution of o-dichlorobenzene / deuterated bromide benzene (C6D5Br) and hexamethyldisiloxane, a chemical shift reference substance, and dissolved uniformly in a block heater at 150°C. NMR measurements are carried out at 120°C using a Bruker Biospin AV400 NMR instrument equipped with a 10 mm diameter cryoprobe. To quantify the number of carbon-carbon double bond ends, 1 H-NMR is used. 1 The H-NMR measurement conditions are a sample temperature of 120°C, a pulse angle of 4.5°, a pulse interval of 2 seconds, and an accumulation count of 512. The chemical shift of the hexamethyldisiloxane proton signal is set to 0.09 ppm, and the chemical shifts of signals due to other protons are based on this. To quantify saturated ends, 13 C-NMR is used. 13 The C-NMR measurement conditions are a sample temperature of 120°C, a pulse angle of 45°, a pulse interval of 18 seconds, an accumulation count of 3072, and broadband decoupling. 13 The C signal was set to 1.98 ppm, and the other 13 The chemical shift of the C signal is based on this.

[0026] 2. Calculation method for the number of carbon-carbon double bond ends Examples of the structure having a vinyl group at the end include the structural formulae (1-a) and (1-f). 1 In H-NMR, the proton signals of the unsaturated bonds of the structural formula (1-a) 1-propenyl and the structural formula (1-f) 1-butenyl are 1 It is detected overlapping with the signals at 5.08-4.85 ppm and 5.86-5.69 ppm in the H-NMR spectrum. Therefore, the number of terminal vinyl groups [Vi] is the total number of 1-propenyl and 1-butenyl groups, and is the amount of unsaturated bonds per 1000 monomers in total: 1 It is calculated using the signal intensity of the H-NMR spectrum according to the following formula: Structural formula (1-a) + Structural formula (1-f): [Vi]=Ivi×1000 / Itotal

[0027] The structure having a vinylidene group at the end is represented by the structural formula (1-b). The number of terminal vinylidene groups [Vd] is the number of propyl vinylidenes, and the amount of unsaturated bonds per 1000 monomers in total is expressed as follows: 1 It is calculated using the signal intensity of the H-NMR spectrum according to the following formula: Structural formula (1-b): [Vd]=Ivd×1000 / Itotal Similarly, the number of i-butenyl groups [i-butenyl], the number of vinylene terminals [terminal vinylene], and the number of internal vinylidenes [internal vinylidene] can be calculated from the following formulas. Structural formula (1-d): [i-butenyl] = Iibu × 1000 / Itotal Structural formula (1-g): [Terminal vinylene] = Ivnl × 1000 / Itotal Structural formula (1-m): [internal vinylidene] = Iivd × 1000 / Itotal

[0028] Here, Ivi, Ivd, Iibu, Ivnl, and Iivd represent characteristic values ​​of signals based on structural formula (1-a) + structural formula (1-f), structural formula (1-b), structural formula (1-d), structural formula (1-g), and structural formula (1-m), respectively, and are quantities represented by the following formulas. Ivi=(I 5.08~4.85 +I 5.86~5.69 ) / 3, Ivd=(I 4.79~4.65 ) / 2, Iibu=I 5.30~5.08 , Ivnl=(I 5.58~5.30 ) / 2, Iivd=(I 4.85~4.79 ) / 2

[0029] I represents the integrated intensity, and the subscripts of I represent the range of chemical shifts. For example, I 5.08~4.85 indicates the integrated intensity of the signal detected between 5.08 ppm and 4.85 ppm. Furthermore, Itotal is the quantity expressed by the following formula. Itotal=IC3+Ivi+Ivd+Iibu+Ivnl+Iivd IC3 represents the characteristic value of the signal based on propylene and is the quantity shown by the following formula. IC3=1 / 6×Imain What is Imain? 1 It is the sum of the proton signals of the polymer main chain and saturated terminals detected between 4.00 pm and 0.00 pm in the H-NMR spectrum.

[0030] 3. Calculation method for the number of saturated ends The number of saturated ends below is the number per 1000 monomers: 13 It is calculated using the signal intensity of the C-NMR spectrum according to the following formula: Structural formula (1-c): [i-butyl]=Ii-butyl×1000 / Itotal-C Structural formula (1-e): [n-butyl]=Inbu×1000 / Itotal-C Structural formula (1-h): [n-propyl] = Inpr × 1000 / Itotal-C Structural formula (1-i): [2,3-dimethylbutyl] = I2,3-dime × 1000 / Itotal-C Structural formula (1-j): [3,4-dimethylpentyl] = I3,4-dime × 1000 / Itotal-C

[0031] Furthermore, the propylene homopolymer of the present disclosure may have the following 2,1 bond and 1,3 bond based on irregular insertion of propylene in addition to the structure based on regular 1,2 insertion of propylene inside the polymer. [ka]

[0032] Here, Ii-butyl, Inbu, Inpr, I2,3-dime, and I3,4-dime represent characteristic values ​​of signals based on structural formula (1-c), structural formula (1-e), structural formula (1-h), structural formula (1-i), and structural formula (1-j), respectively, and are quantities represented by the following formulas. Ii-butyl=(I 23.80~23.70 +I 25.80~25.70 ) / 2 Inbu=I 14.06~14.02 Inpr=(I 14.44~14.42 +I 30.46~30.45 ) / 2 I2,3-dime=(I 16.21~16.17 +I 31.86~31.81 ) / 2 I3,4-dime=I 12.0~11.60

[0033] Furthermore, Itotal-C is the quantity expressed by the following formula. Itotal-C=Ii-butyl+Inbu+Inpr+I2,3-dime+I3,4-dime+I1,2-P+I2,1-P+I1,3-P I1,2-P represents the characteristic value of the signal based on the 1,2-inserted propylene bond, I2,1-P represents the characteristic value of the signal based on the 2,1-inserted propylene bond, and I1,3-P represents the characteristic value of the signal based on the 1,3-inserted propylene bond, and are quantities expressed by the following formulas. I1,2-P=I48.80~44.50 I2,1-P=(I 35.72~35.63 +I 35.83~35.77 ) / 2 I1,3-P=I 37.41-37.21 / 2

[0034] 4. Calculation method for total number of terminals The total number of ends is 13 C-NMR and 1 It is the total number of terminals per 1000 monomer units calculated by each H-NMR, specifically, the sum of the numbers of terminals of the structural formulas (1-a) to (1-j) per 1000 monomer units.

[0035] 5.How to calculate the number of LCBs The double bond-containing polypropylene may have a long chain branched (LCB) structure portion. The number of long chain branches (LCB number) is 13 The number per 1,000 propylene monomer units is calculated by the following formula using the integrated signal intensities of the branch point carbon (methine carbon) at 31.72 to 31.66 ppm and three methylene carbons bonded to the branch point carbons (methine carbon) at 44.09 to 44.03 ppm, 44.78 to 44.72 ppm, and 44.90 to 44.84 ppm, when the intensity of the methylene carbon in the propylene main chain at 49.00 to 44.33 ppm is normalized to 1,000 by C-NMR. Number of LCBs = [(I 44.09~44.03 +I 44.78~44.72 +I 44.90~44.84 +I 31.72~31.66 ) / 4] / I 49.00~44.33

[0036] [Compound represented by general formula [I]] The compound represented by general formula [I] has a nitrile oxide group, which is a 1,3-dipole functional group. The nitrile oxide group can undergo a 1,3-dipole cycloaddition reaction with the unsaturated bond of a double-bond-containing polyolefin in the absence of a catalyst, forming an isoxazoline skeleton. Furthermore, the compound represented by general formula [I] is advantageous in that the nitrile oxide group is less likely to dimerize, allowing the 1,3-dipole cycloaddition reaction to proceed. The compound represented by general formula [I] may be used alone or in combination of two or more types. [ka]

[0037] In the general formula [I], s is an integer of 2 to 4. From the viewpoint of suppressing reactions between polymers, s is preferably an integer of 2 to 3, and more preferably 2.

[0038] R 1 and R 2 are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms. Examples of the hydrocarbon group having 4 to 10 carbon atoms or the halogenated hydrocarbon group having 4 to 10 carbon atoms include a tert-butyl group, an isobutyl group, a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-chlorophenyl group, a 2,4-dimethylphenyl group, and a 3,4-dimethylphenyl group. R 1 and R 2 As the aryl group, an aryl group having 6 to 8 carbon atoms is preferred because the nitrile oxide group is less likely to dimerize. Examples of the aryl group having 6 to 8 carbon atoms include a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 2,4-dimethylphenyl group, and a 4-chlorophenyl group, with a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, and a 2,4-dimethylphenyl group being preferred, and a phenyl group being more preferred. R 1 and R 2 may be the same or different. 1 and R2 are preferably the same, since this increases the molecular symmetry, makes the compound more likely to solidify, and provides excellent storage stability at room temperature.

[0039] X's each independently represent a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )-. X is preferably -O-, -S-, or -N(R 3 )- is preferred, -O- or -S- is preferred, and -O- is more preferred. R 3 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. Examples of the hydrocarbon group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, and a hexyl group. R 3 As the alkyl group, a hydrogen atom or a methyl group is preferred in terms of ease of compound synthesis. The divalent hydrocarbon group for X includes alkylene groups having 1 to 3 carbon atoms, arylene groups having 6 to 8 carbon atoms, and combinations thereof.

[0040] A is an s-valent organic group. The organic group essentially contains a carbon atom, and optionally contains a hydrogen atom, an oxygen atom, a chlorine atom, a nitrogen atom, a sulfur atom, etc. Examples of the organic group include hydrocarbon groups (alkylene groups, arylene groups, etc.), combinations of hydrocarbon groups and various bonds (-O-, -C(=O)-, -S-, -S(=O)2-, etc.), combinations of hydrocarbon groups and polar functional groups (hydroxy groups, mercapto groups, carboxy groups, amino groups, amide groups, alkoxy groups, etc.), and combinations of hydrocarbon groups, various bonds, and polar functional groups.

[0041] As the compound represented by the general formula [I], the following nitrile oxide compounds (i) to (ii) are preferred, since they tend to have a high melting point and are excellent in storage stability at room temperature. (i) A nitrile oxide compound in which, in the general formula [I], s is 2 and A is an alkylene group having 2 to 10 carbon atoms. (ii) A nitrile oxide compound in which, in the general formula [I], s is 2 and A is a group represented by the general formula [III] described below.

[0042] By introducing a highly symmetrical alkylene group having a short carbon chain as in (i), the melting point of the nitrile oxide compound can be increased. By introducing a group represented by the general formula [III] having a highly symmetrical and rigid arylene group as in (ii), the melting point of the nitrile oxide compound can be increased.

[0043] A in (i) is an alkylene group having 2 to 10 carbon atoms. As A in (i), from the viewpoint of solidifying the nitrile oxide compound and exhibiting a melting point close to that of polyolefin, an alkylene group having 3 to 8 carbon atoms is preferred, and an alkylene group having 4 to 6 carbon atoms is more preferred. Examples of A in (i) include a 1,2-ethylene group, a 1,3-propylene group, a 2-methyl-1,3-propylene group, a 2,2-dimethyl-1,3-propylene group, a 1,4-butylene group, a 1,5-pentylene group, a 1,6-hexylene group, a 1,7-heptylene group, a 1,8-octylene group, a 3-methyl-1,5-pentylene group, a 1,4-cyclohexylene group, a 1,4-cyclohexadimethylene group, a 1-methyl-1,2-ethylene group, and a 1-methyl-1,3-propylene group. In (i), A is preferably a 1,3-propylene group, a 1,4-butylene group, a 1,6-hexylene group, a 1,4-cyclohexadimethylene group, a 1,4-cyclohexylene group, or a 3-methyl-1,5-pentylene group, and more preferably a 1,4-butylene group, a 1,6-hexylene group, or a 3-methyl-1,5-pentylene group.

[0044] In (ii), A is a group represented by the general formula [III]. -(R 4 ′-O) t -R 5 ′-(OR 4 ′) t - [III]

[0045] t is 0 or 1. t is preferably 1 from the viewpoint of ease of production of the nitrile oxide compound, and is preferably 0 from the viewpoint of the melting point of the nitrile oxide compound. R 4′ is an alkylene group having 2 to 4 carbon atoms. 4′ Examples of R include a 1,2-ethylene group and a 1,3-propylene group. 4′ As the alkyl group, a 1,2-ethylene group is preferred because the melting point of the nitrile oxide compound can be increased as the number of carbon atoms decreases.

[0046] R 5′ is a group represented by general formula [IV] or a group represented by general formula [V]. 5′ As the functional group, a group represented by the general formula [V] is preferred from the viewpoint of increasing the distance between the terminal end of the polyolefin and the introduced functional group after modification of the double bond-containing polyolefin and increasing the reactivity of the modified polyolefin.

[0047] [ka]

[0048] R 6′ ~R 9′ are each independently a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or a halogen atom, and R 6′ and R 7′ may be linked to form an aromatic ring or an aliphatic ring, R 8′ and R 9′ may be linked to form an aromatic ring or an aliphatic ring. Examples of hydrocarbon groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, hexyl, cyclohexyl, and phenyl groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. R 6′ ~R 9′ As the alkyl group, a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a phenyl group, and a chlorine atom are preferred, a hydrogen atom, a methyl group, an isopropyl group, and a tert-butyl group are more preferred, and a hydrogen atom and a methyl group are even more preferred.

[0049] R 10′ ~R 17′ are each independently a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or a halogen atom, and R 10′ and R 11′ may be linked to form an aromatic ring or an aliphatic ring, R 12′ and R 13′ may be linked to form an aromatic ring or an aliphatic ring, R 14′ and R 15′ may be linked to form an aromatic ring or an aliphatic ring, R 16′ and R 17′ may be linked to form an aromatic ring or an aliphatic ring. Examples of hydrocarbon groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, hexyl, cyclohexyl, and phenyl groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. R 10′ ~R 17′ As the alkyl group, a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a phenyl group, and a chlorine atom are preferred, a hydrogen atom, a methyl group, an isopropyl group, and a tert-butyl group are more preferred, and a hydrogen atom and a methyl group are even more preferred.

[0050] u is 0 or 1. u is preferably 1, since it increases the distance between the terminal end of the polyolefin and the introduced functional group after modification of the double bond-containing polyolefin, thereby enhancing the reactivity of the modified polyolefin. Q is -C(R 18′ )(R 19′ )-, -C(=O)-, -S- or -S(=O)2-. Q is preferably -C(R 18′ )(R 19′ )- is more preferred. R 18′ and R 19′ are each independently a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or a halogen atom, and R 18′ and R 19′may be linked to form an aromatic ring or an aliphatic ring. Examples of hydrocarbon groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, hexyl, cyclohexyl, and phenyl groups. R 18′ and R 19′ An example of a bonded group is a 1,1-cyclohexylene group. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. 18′ and R 19′ is preferably a hydrogen atom, a methyl group, an ethyl group or a phenyl group.

[0051] The melting point of the compound represented by general formula [I] is preferably 25 to 300°C, more preferably 40 to 280°C, even more preferably 60 to 260°C, and particularly preferably 80 to 240°C. If the melting point of the compound is equal to or higher than the lower limit of the above range, the mobility at room temperature decreases, thereby improving storage stability at room temperature. If the melting point of the compound is equal to or lower than the upper limit of the above range, the compound is more likely to melt during the melting reaction, thereby increasing reactivity. In order to increase the melting point of the compound represented by general formula [I] to 25°C or higher, for example, a highly symmetric structure may be added to A to increase the symmetry of the molecular structure, or a highly rigid group or a short-chain group may be introduced into A.

[0052] [Method of producing modified polyolefin] A method for producing a modified polyolefin comprises subjecting a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more to an addition reaction with a compound represented by general formula [I]. The production method comprises, in any order, a step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound represented by general formula [I], and a step of converting at least one nitrile oxide group in the compound to an isocyanate group. The production method of the present invention makes it possible to produce a modified polyolefin having at least one isoxazoline skeleton and at least one isocyanate group in a short process under industrially advantageous conditions.

[0053] The amount of the compound represented by general formula [I] is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 8 parts by mass, and even more preferably 0.05 to 6 parts by mass, per 100 parts by mass of the double-bond-containing polyolefin. The amount of the compound represented by general formula [I] is preferably 0.1 to 8.0 equivalents, more preferably 0.5 to 5.0 equivalents, and even more preferably 1.0 to 3.0 equivalents, per equivalent of the carbon-carbon double bond of the double-bond-containing polyolefin.

[0054] (Isomerization accelerator) The step of converting at least one nitrile oxide group in the compound represented by the general formula [I] into an isocyanate group is preferably carried out in the presence of an isomerization accelerator. The isomerization accelerator is a component that accelerates the reaction of converting the nitrile oxide group of the compound into an isocyanate group. By subjecting a double bond-containing polyolefin and the compound to an addition reaction in the presence of the isomerization accelerator, a polyolefin modified with at least one isoxazoline skeleton and at least one isocyanate group can be efficiently produced in a short process.

[0055] Examples of the isomerization accelerator include compounds of fatty acids such as stearic acid and lauric acid, fatty acid amides such as stearic acid amide and oleic acid amide, and fatty acid metal salts such as calcium stearate, calcium laurate, and zinc octylate. From the viewpoint of isomerization acceleration efficiency, those having stearic acid as the main skeleton are more preferred, and calcium stearate is even more preferred. One type of isomerization accelerator may be used alone, or two or more types may be used in combination.

[0056] The amount of the isomerization accelerator is preferably 0.001 to 10 parts by mass, more preferably 0.005 to 8 parts by mass, and even more preferably 0.01 to 6 parts by mass, relative to 100 parts by mass of the double-bond-containing polyolefin. The amount of the isomerization accelerator is preferably 0.005 to 1 equivalent, more preferably 0.01 to 0.8 equivalent, and even more preferably 0.05 to 0.4 equivalent, relative to 1 equivalent of the carbon-carbon double bond of the double-bond-containing polyolefin.

[0057] The polyolefin modified product can be obtained, for example, by mixing a double bond-containing polyolefin and a compound represented by general formula [I] in the presence or absence of an isomerization accelerator, followed by heat treatment. The heat treatment may be carried out in a solvent, or may be carried out while melt-kneading in the substantial absence of a solvent.

[0058] Examples of the solvent include hydrocarbons (toluene, xylene, hexane, cyclohexane, etc.). When a solvent is used, the mixing temperature is preferably 50 to 200° C., more preferably 60 to 180° C., and even more preferably 80 to 150° C. When a solvent is used, the mixing time is preferably 30 minutes to 24 hours, more preferably 1 to 15 hours, and even more preferably 2 to 10 hours.

[0059] From the viewpoint of productivity, the heat treatment is preferably carried out by melt-kneading in the substantial absence of a solvent to add-react the double bond-containing polyolefin with the compound represented by general formula [I].

[0060] Examples of the melt-kneading method include a method using a known device such as a twin-screw extruder, a Banbury mixer, etc. Details of the melt-kneading method are described, for example, in "Thermoplastic Elastomers 2nd ed.", Hanser Gardner Publications, 1996, pp. 153-190. When melt-kneading is performed, all of the components may be melt-kneaded at once, or some of the components may be melt-kneaded first, and then the remaining components may be added and melt-kneaded. Melt-kneading may be performed two or more times. After melt-kneading, additional heat treatment may be performed.

[0061] When a solvent is substantially absent, that is, when melt-kneading is performed, the melt-kneading temperature is preferably 80 to 300° C. By melt-kneading a mixture of a double-bond-containing polyolefin and a compound represented by general formula [I] at 80 to 300° C., the step of adding reacting the double bond of the polyolefin with at least one nitrile oxide group of the compound and the step of converting at least one nitrile oxide group of the compound to an isocyanate group can be performed in a single operation, which is advantageous in terms of productivity. The melt-kneading temperature is more preferably 100 to 280° C., and even more preferably 120 to 260° C. The kneading time refers to the residence time in melt-kneading using an extruder. The melt-kneading time is preferably 1 second to 30 minutes, and more preferably 10 seconds to 5 minutes.

[0062] (Mechanism of action) In the method for producing a modified polyolefin of the present invention described above, a polyolefin having a carbon-carbon double bond is used, and therefore the polyolefin can be modified with the compound represented by general formula (I) under industrially advantageous high-temperature conditions.

[0063] <Modified polyolefin> The modified polyolefin is obtained by a method for producing a modified polyolefin, and has at least one isoxazoline skeleton and at least one isocyanate group.

[0064] In another embodiment of the present invention, the modified polyolefin is represented by the following general formula [II]: [ka] s is an integer from 2 to 4, n is an integer from 1 to 3, s>n, R 1 and R 2are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms, X's each independently represent a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )- and R 3 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, A is an s-valent organic group, R 4 , R 5 and R 6 are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R 7 is the backbone of the polyolefin.

[0065] In the general formula [II], s is an integer of 2 to 4. From the viewpoint of suppressing an increase in viscosity of the modified polyolefin, s is preferably an integer of 2 to 3, and more preferably 2.

[0066] n is an integer of 1 to 3. From the viewpoints of use as a filler dispersant for the modified polyolefin and of producing a block copolymer by reaction with other resins, n is preferably an integer of 1 to 2, and particularly preferably 1, with the proviso that s>n.

[0067] R 1 and R 2 are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms. 1 and R 2 Examples of the formula include R 1 and R 2 The same can be mentioned as above, and the preferred embodiments are also the same.

[0068] X's each independently represent a divalent hydrocarbon group, -O-, -S-, or -N(R 3 )- and R 3 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. A is an s-valent organic group. X, R 3Examples of A include X, R in the general formula [I]. 3 and A, and preferred embodiments are also the same.

[0069] R 4 , R 5 and R 6 are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, an isopropyl group, an n-propyl group, an n-butyl group, and an n-hexyl group. R 4 As R, a hydrogen atom, a methyl group, an ethyl group, an n-butyl group, and an n-hexyl group are preferred. 5 and R 6 As the alkyl group, a hydrogen atom and a methyl group are preferred, and a hydrogen atom is more preferred, from the viewpoint of reducing steric hindrance around the double bond and increasing reactivity.

[0070] R 7 is the main chain of the polyolefin. Examples of the polyolefin include the same "polyolefin" as in the double bond-containing polyolefin, and preferred embodiments are also the same.

[0071] (Structure identification of modified polyolefins) The isoxazoline skeleton of the modified polyolefin is identified as follows: 1 This can be done by H-NMR. Specifically, the modified polyolefin is placed in an NMR sample tube with an inner diameter of 10 mm together with a mixed solution of o-dichlorobenzene / deuterated bromide benzene (CDBr) and hexamethyldisiloxane, a chemical shift reference material, and dissolved uniformly in a block heater at 150°C. NMR measurements are performed at 120°C using a Bruker Biospin AV400 NMR instrument equipped with a 10mm diameter cryoprobe.

[0072] FIG. 1 shows the modified polyolefin of Example 4. 1 The modified polyolefin of Example 4 is a polyolefin having a R 4 , R 5 and R 6are all hydrogen atoms, but as shown in Figure 1, R 4 The hydrogen atom signals of R were observed in the range of 4.1 to 4.8 ppm. 5 and R 6 The hydrogen atom signals are observed in the range of 2.3 to 3.0 ppm, and based on this, the isoxazoline skeleton can be identified. 4 , R 5 and R 6 Similarly, when is an alkyl group having 1 to 8 carbon atoms, 1 The isoxazoline skeleton can be identified by H-NMR.

[0073] The isocyanate group in the modified polyolefin can be identified by IR measurement. Specifically, a pressed piece of 40 mm × 30 mm × 0.5 mmt was prepared using pellets of the modified polyolefin, and IR measurement was performed. -1 The absorbance of the isocyanate group is calculated from the peak height of the isocyanate group observed around 2210 cm. -1 and 2310cm -1 2243cm when the line connecting -1 is the peak height of

[0074] <Composition> The modified polyolefin may be blended with other components (resins, fillers, additives, etc.) to form a composition. The other components may be blended before, during, or after the modification of the double bond-containing polyolefin. The amount of the other components added is usually 0.001 to 200 parts by mass per 100 parts by mass of the modified polyolefin.

[0075] Examples of the filler include inorganic fillers (talc, calcium carbonate, calcined kaolin, etc.) and organic fillers (fibers, wood flour, cellulose powder, etc.). Examples of additives include antioxidants (phenolic, sulfur-based, phosphorus-based, lactone-based, vitamin-based, etc.), weather stabilizers, ultraviolet absorbers (benzotriazole-based, tridiamine-based, anilide-based, benzophenone-based, etc.), heat stabilizers, light stabilizers (hindered amine-based, benzoate-based, etc.), antistatic agents, nucleating agents, pigments, adsorbents (metal oxides such as zinc oxide and magnesium oxide), metal chlorides (iron chloride, calcium chloride, etc.), hydrotalcite, aluminates, lubricants, mineral oil, and silicone compounds.

[0076] <Applications of modified polyolefins> The modified polyolefin has at least one isoxazoline skeleton and at least one isocyanate group. Because the modified polyolefin has at least one isocyanate group, it is useful as a reactant with compounds having active hydrogen, such as amine groups or hydroxyl groups. The modified polyolefin can be suitably used as a crosslinking agent or modifier in metal, woodwork, automotive repair paints, etc. [Example]

[0077] The present invention will be explained in more detail below based on examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention.

[0078] <Measurement of physical properties, analysis, etc.> (DSC measurement) The melting point (Tm) of the double bond-containing polyolefin was determined by differential scanning calorimetry (DSC). The sample was heated to 200°C, allowed to stand for 5 minutes, then cooled to 40°C at a rate of 10°C / min, and measured again at a rate of 10°C / min. The melting point was determined as the temperature at the top of the endothermic peak. The unit is °C.

[0079] (Calculation method for carbon-carbon double bond terminal ratio) The carbon-carbon double bond terminal ratio of the double bond-containing polyolefin was calculated in accordance with JP 2021-4376 A. 200 mg of sample was placed in a 10 mm diameter NMR sample tube together with 2.4 ml of a mixed solution of o-dichlorobenzene / deuterated bromide benzene (CDBr) and hexamethyldisiloxane, a chemical shift reference material, and dissolved homogeneously in a block heater at 150 °C. NMR measurements were performed at 120 °C using a Bruker Biospin AV400 NMR instrument equipped with a 10 mm diameter cryoprobe.

[0080] To quantify the number of carbon-carbon double bond ends, 1 H-NMR was used. 1 The H-NMR measurement conditions were a sample temperature of 120°C, a pulse angle of 4.5°, a pulse interval of 2 seconds, and an accumulation count of 512. The chemical shift of the hexamethyldisiloxane proton signal was set to 0.09 ppm, and the chemical shifts of the signals due to other protons were set to this as the reference. To quantify the number of saturated ends and LCBs, 13 C-NMR was used. 13 The C-NMR measurement conditions were a sample temperature of 120°C, a pulse angle of 45°, a pulse interval of 18 seconds, and an accumulation count of 3072. Measurements were performed using the broadband decoupling method. 13 The C signal was set to 1.98 ppm, and the other 13 The chemical shift of the C signal was based on this.

[0081] The above 1 H-NMR and 13 Based on the C-NMR measurement results and in accordance with the method described in the specification, the total number of carbon-carbon double bond ends, the total number of ends, and the number of LCBs were calculated, and the carbon-carbon double bond end ratio was calculated using the following formula. (Carbon-carbon double bond terminal rate) = (total number of carbon-carbon double bond terminals) / {((total number of terminals) - (number of LCBs)) ÷ 2} × 100 Here, the total number of carbon-carbon double bond terminals is 1 The total number of carbon-carbon double bond ends per 1,000 monomer units is calculated by H-NMR. 1 H-NMR and 13The LCB number is the total number of terminals per 1000 monomer units calculated by C-NMR. 13 This is the number of methine carbon atoms at the base of branched chains with 7 or more carbon atoms per 1,000 monomer units calculated by C-NMR.

[0082] (Identification of isoxazoline skeleton) The isoxazoline skeleton of the modified polyolefin is identified as follows: 1 The measurements were performed using H-NMR. Specifically, the modified polyolefin was placed in an NMR sample tube with an inner diameter of 10 mm together with a mixed solution of o-dichlorobenzene / deuterated bromide benzene (CDBr) and hexamethyldisiloxane, a chemical shift reference material, and dissolved uniformly in a block heater at 150°C. NMR measurements were performed at 120°C using a Bruker Biospin AV400 NMR instrument equipped with a 10mm diameter cryoprobe.

[0083] (Isocyanate group identification) The isocyanate group in the modified polyolefin was identified by IR measurement. Specifically, a pressed piece of 40 mm × 30 mm × 0.5 mmt was prepared using pellets of the modified polyolefin, and IR measurement was performed. -1 The absorbance of the isocyanate group was calculated from the peak height of the isocyanate group observed around 2210 cm. -1 2243 cm when the line connecting 2310 cm-1 and 2310 cm-1 is used as the baseline -1 is the peak height of If the absorbance was 0.1 or higher, it was determined that the isocyanate groups had been sufficiently introduced into the modified polyolefin, and if it was 0.3 or higher, it was determined that it was particularly excellent.

[0084] <Double bond-containing polyolefin> (PP1: propylene homopolymer) Tm=156℃, carbon-carbon double bond termination rate=65.2% (PP2: propylene homopolymer) Tm=155℃, carbon-carbon double bond termination rate=95.8% (PP3: propylene homopolymer) Tm=147℃, carbon-carbon double bond termination rate=100.9% (PP4: Propylene homopolymer) Tm=162℃, carbon-carbon double bond termination rate=18.2%

[0085] <Compound represented by general formula [I]> A compound represented by the following formula [VI] Synthesized according to Example 2A of WO 2019 / 107450. [ka]

[0086] <Isomerization accelerator> Calcium stearate (NOF Corporation, calcium stearate)

[0087] <Production of modified polyolefin> (Example 1 7 and Comparative Example 1 , 8 and 9 ) For the production of the polyolefin modified material, a twin-screw kneader "KZW15" manufactured by Technobel Co., Ltd. was used. A mixture was obtained by mixing 300 g of a double bond-containing polyolefin, a compound represented by formula [VI] in an amount equivalent to 2 times the carbon-carbon double bond of the polyolefin, and a predetermined amount of calcium stearate in a plastic bag. The calcium stearate was used in an amount equivalent to the carbon-carbon double bond of the polyolefin shown in Table 1. The entire mixture in the plastic bag was placed in the feeder of a KZW15 preheated to 180°C, and the reaction was initiated at a screw speed of 400 rpm. After melt-kneading for 10 seconds, the resulting strand was cut from the die outlet and the pellets were collected.

[0088] In order to remove unreacted isocyanate compounds from the recovered pellets, they were purified by ultrasonic solvent extraction according to the description of JP 2016-173328 A. Specifically, the recovered pellets were formed into a film with a thickness of 0.1 mm or less, cut into approximately 1 cm square pieces with scissors, and placed in a flask together with a chloroform / acetone mixed solvent as the extraction solvent, and fixed in an ultrasonic extractor set at approximately 60 ° C. In this state, ultrasonic extraction was performed for 75 minutes, and the film was filtered off with filter paper to obtain a polyolefin modified product.

[0089] The absorbance results for the Examples and Comparative Examples are shown in Table 1. 1 The H NMR spectrum is shown in Figure 1. As shown in Figure 1, R 4 The hydrogen atom signals of R were observed in the range of 4.1 to 4.8 ppm. 5 and R 6 The signal of the hydrogen atom was observed in the range of 2.3 to 3.0 ppm, and based on this, the presence of the isoxazoline skeleton was confirmed. 7 and Comparative Example 8 and Similarly, for the polyolefin modified product of 9, 1 The presence of the isoxazoline skeleton was confirmed by 1 H-NMR spectroscopy.

[0090] [Table 1]

[0091] <Consideration> As shown in Table 1, it can be seen that by subjecting a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more to an addition reaction with a compound represented by general formula [I], it is possible to introduce an isocyanate group into the polyolefin in a short process under industrially advantageous conditions. Comparative Example Comparison of Example 8 and Example 4 Comparative Example 9, Examples 1 and 4, in which melt-kneading was carried out in the presence of an isomerization accelerator, are preferred because they have high absorbance of the isocyanate group and a high rate of introduction of the isocyanate group into the polyolefin.

[0092] The polyolefin modified product of Comparative Example 1, which used a polyolefin with a carbon-carbon double bond terminal ratio of less than 20%, had low absorbance of the isocyanate group, and the isocyanate group could not be sufficiently introduced into the polyolefin, even though it was melt-kneaded in the presence of an isomerization accelerator. [Industrial Applicability]

[0093] The production method of the present invention allows for the production of a polyolefin modified product having an isocyanate group introduced therein in a short number of steps under industrially advantageous conditions. Furthermore, the resulting polyolefin modified product can be used as a crosslinking agent or modifier, and is suitable for use in metal, woodwork, automotive repair paints, etc. Thus, the production method of the present invention has extremely great industrial value.

Claims

1. A method for producing a modified polyolefin, comprising adding a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more with a compound represented by the following general formula [I]: the modified polyolefin has at least one isoxazoline skeleton and at least one isocyanate group, The method comprises, in any order, a step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and a step of converting at least one nitrile oxide group of the compound to an isocyanate group in the presence of an isomerization accelerator; The production method, wherein the isomerization accelerator is at least one of a fatty acid-based compound, a fatty acid amide-based compound, and a fatty acid metal salt-based compound. 【Chemistry 1】 In the general formula [I], s is an integer from 2 to 4, R １ and R ２ are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms, X's each independently represent a divalent hydrocarbon group, -O-, -S-, or -N(R ３ ) - and R ３ is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, A is an s-valent organic group.

2. A method for producing a modified polyolefin, comprising adding a polyolefin having a carbon-carbon double bond terminal ratio of 20% or more with a compound represented by the following general formula [I]: The polyolefin modified product is represented by the following general formula [II]: The method comprises, in any order, a step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and a step of converting at least one nitrile oxide group of the compound to an isocyanate group in the presence of an isomerization accelerator; The production method, wherein the isomerization accelerator is at least one of a fatty acid-based compound, a fatty acid amide-based compound, and a fatty acid metal salt-based compound. 【Chemistry 2】 【Transformation 3】 In the general formulas [I] and [II], s is an integer from 2 to 4, n is an integer from 1 to 3, s>n, R １ and R ２ are each independently a hydrocarbon group having 4 to 10 carbon atoms or a halogenated hydrocarbon group having 4 to 10 carbon atoms, X's each independently represent a divalent hydrocarbon group, -O-, -S-, or -N(R ３ ) - and R ３ is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, A is an s-valent organic group; R ４ , R ５ and R ６ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R ７ is the backbone of the polyolefin.

3. A method for producing a polyolefin modified body described in claim 1 or 2, wherein the fatty acid compound is stearic acid or lauric acid, the fatty acid amide compound is stearic acid amide or oleic acid amide, and the fatty acid metal salt compound is calcium stearate, calcium laurate, or zinc octylate.

4. The method for producing a modified polyolefin according to claim 1 or 2, wherein the polyolefin and the compound are subjected to an addition reaction in the substantial absence of a solvent.

5. 3. The method for producing a modified polyolefin according to claim 1 or 2, wherein the step of subjecting a double bond of the polyolefin to an addition reaction with at least one nitrile oxide group of the compound, and the step of converting at least one nitrile oxide group of the compound to an isocyanate group are carried out in a single operation of melt-kneading a mixture of the polyolefin and the compound at 80 to 300°C.

6. The method for producing a modified polyolefin according to claim 1 or 2, wherein the carbon-carbon double bond of the polyolefin is a vinyl group or a vinylidene group.

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