Modified polyolefin resin and method for producing same

Abstract

This modified polyolefin resin includes a product of modification of a polyolefin resin with a modifying component, wherein the modifying component comprises one or more compounds selected from the group consisting of α,β-unsaturated carboxylic acids and derivatives thereof. The modified polyolefin resin gives a Fourier-transform infrared absorption spectrum which has a peak having a peak-top wavenumber of 1,786.0 cm-1 to 1,795.0 cm-1 inclusive.

Description

Modified polyolefin resin and method for producing the same

[0001] The present invention relates to a modified polyolefin resin and a method for producing the same.

[0002] Modified polyolefin resins are known, which are obtained by modifying polyolefin resins containing olefin polymers with components containing α,β-unsaturated carboxylic acids and / or derivatives thereof. It is also known that resin compositions containing modified polyolefin resins are used as adhesives (see Patent Document 1). Furthermore, it is known that the modification of polypropylene is carried out in the presence of α-methylstyrene dimer (2,4-diphenyl-4-methyl-1-pentene: hereinafter also referred to as αMSD) (see Patent Documents 2 to 5, etc.).

[0003] International Publication No. 2019 / 188858, Japanese Patent Publication No. 2023-166173, Japanese Patent Publication No. 2023-136186, Japanese Patent Publication No. Hei 6-172459, Japanese Patent Publication No. Hei 11-236421

[0004] Modified polyolefin resins are used as components of adhesives due to their adhesive properties. For example, in cases where adhesion at high temperatures (e.g., 120°C or higher) is required, such as in adhesives used for lithium-ion battery packaging, the modified polyolefin resin used as a component of the adhesive must have excellent adhesion at high temperatures. Therefore, there is a need for a modified polyolefin resin having excellent adhesion at high temperatures; a method for producing such a modified polyolefin resin; and a primer, adhesive, paint, or ink containing such a modified polyolefin resin.

[0005] The inventors have found that when the polymer structure of α,β-unsaturated carboxylic acids and / or their derivatives grafted onto the main chain of a modified polyolefin resin is small, it exhibits excellent adhesion at high temperatures. The inventors hypothesized that a modified polyolefin resin in which α,β-unsaturated carboxylic acids and / or their derivatives are uniformly or nearly uniformly grafted onto the modified polyolefin resin chain can potentially form a crosslinked structure with high uniformity. Therefore, the inventors hypothesized that if an adhesive containing a combination of a modified polyolefin resin and a curing agent is placed between the members to be bonded, and then a curing reaction proceeds in the adhesive, a crosslinked structure will be formed between the main chains of the modified polyolefin resin at a high density, allowing the modified polyolefin resin to possess high heat resistance in addition to adhesion. Based on the above findings, the inventors conducted research and found that a certain modified polyolefin resin can solve the above problem, and thus completed the present invention. The present invention provides the following.

[0006] <1> A modified polyolefin resin comprising a modified polyolefin resin by a modifying component, wherein the modifying component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, and the Fourier transform infrared absorption spectrum of the modified polyolefin resin has a peak wavenumber of 1786.0 cm⁻¹. －１ 1795.0cm or more －１A modified polyolefin resin having the following peaks: <2> The modified polyolefin resin according to <1>, further comprising a chain transfer agent. <3> The modified polyolefin resin according to <2>, wherein the chain transfer agent has an aliphatic hydrocarbon group having 5 or more carbon atoms. <4> The modified polyolefin resin according to <2> or <3>, wherein the chain transfer agent is a thiol-based chain transfer agent. <5> The modified polyolefin resin according to any one of <2> to <4>, wherein the chain transfer agent comprises one or more selected from the group consisting of 1-dodecanethiol and 2-ethylhexyl 3-mercaptopropionate. <6> The modified polyolefin resin according to any one of <2> to <5>, wherein the content of the chain transfer agent is 1 to 5% by weight, based on 100% by weight of the polyolefin resin. <7> A resin composition comprising the modified polyolefin resin according to any one of <1> to <6>. <8> A primer comprising a modified polyolefin resin according to any one of <1> to <6> or a resin composition according to <7>. <9> An adhesive comprising a modified polyolefin resin according to any one of <1> to <6> or a resin composition according to <7>. <10> A paint comprising a modified polyolefin resin according to any one of <1> to <6> or a resin composition according to <7>. <11> An ink comprising a modified polyolefin resin according to any one of <1> to <6> or a resin composition according to <7>. <12-1> A method for producing a modified polyolefin resin, wherein the modified polyolefin resin comprises a modified product of a polyolefin resin by a modifying component, the modifying component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, and the Fourier transform infrared absorption spectrum of the modified polyolefin resin has a peak wavenumber of 1786.0 cm. －１ 1795.0cm or more －１A method for producing a modified polyolefin resin, wherein the production method comprises (a) heating a composition comprising the polyolefin resin, a chain transfer agent, and the modifying component, and step (a) is performed at a temperature of 150°C to 190°C. <12-2> A method for producing a modified polyolefin resin, wherein the modified polyolefin resin comprises a modified product of the polyolefin resin by the modifying component, the modifying component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, and the Fourier transform infrared absorption spectrum of the modified polyolefin resin has a peak wavenumber of 1786.0 cm⁻¹. －１ 1795.0cm or more －１ A method for producing a modified polyolefin resin, wherein the production method comprises (a) heating a composition comprising the polyolefin resin, a thiol-based chain transfer agent, and the modified component, wherein step (a) is performed at a temperature of 150°C to 190°C, and the content of the thiol-based chain transfer agent in the composition is 2% by weight or more relative to 100% by weight of the polyolefin resin. <13> A method for producing a modified polyolefin resin according to <12-1> or <12-2>, wherein step (a) is performed in an extruder. <14> A method for producing a modified polyolefin resin according to any one of <12-1>, <12-2>, and <13>, wherein the composition in step (a) does not contain a solvent or the content of the solvent is 0.1% by weight or less, with the weight percentage of the composition being 100% by weight.

[0007] According to the present invention, it is possible to provide a modified polyolefin resin having excellent adhesion at high temperatures; a method for producing such a modified polyolefin resin; and a primer, adhesive, paint, or ink containing such a modified polyolefin resin.

[0008] The components of the embodiments shown below can be combined as appropriate. For example, any numerical value selected from the group of numerical values ​​listed as the lower limit and any numerical value selected from the group of numerical values ​​listed as the upper limit can be combined as appropriate.

[0009] In the following description, unless otherwise specified, the description "AA to BB" means "AA or more and BB or less". Here, AA and BB each represent a numerical value, and AA < BB. The unit of AA is the same as the unit given for BB unless otherwise specified.

[0010] In the following description, unless otherwise specified, the term "(meth)acrylic acid" includes "acrylic acid", "methacrylic acid" and combinations thereof, and the term "(meth)acrylate" includes "acrylate", "methacrylate" and combinations thereof.

[0011] A structural unit having a structure formed by polymerizing a certain monomer is referred to as a "monomer unit" by adding "unit" after the name of the monomer. However, the "monomer unit" is not limited by its formation method. For example, a structural unit formed by graft polymerization of maleic anhydride onto an olefin polymer is referred to as a maleic anhydride unit. The monomer unit may be a repeating unit or may be a single non-repeating unit.

[0012] <1. Modified Polyolefin Resin> A modified polyolefin resin according to one embodiment of the present invention includes a modified product of a polyolefin resin modified by a modifying component, the modifying component includes one or more selected from the group consisting of α,β-unsaturated carboxylic acids and derivatives thereof, and in the Fourier transform infrared absorption spectrum of the modified polyolefin resin, the peak has a wavenumber at its apex of 1786.0 cm －１ or more and 1795.0 cm －１ or less.

[0013] The modified polyolefin resin has excellent adhesion at high temperatures (for example, 120°C).

[0014] <1.1. Fourier Transform Infrared Absorption Spectrum of Modified Polyolefin Resin> In the Fourier transform infrared absorption spectrum of the modified polyolefin resin, the peak has a wavenumber at its apex of 1786.0 cm －１ or more and 1795.0 cm －１ or less. A modified polyolefin resin having such a peak has excellent adhesion at high temperatures.

[0015] The reason why modified polyolefin resins with such peaks exhibit excellent adhesion at high temperatures is presumed to be as follows: The wavenumber at the peak is 1786.0 cm. －１ 1795.0cm or more －１ The peaks shown below are typically identified as the stretching vibrations of the carbonyl group of an α,β-unsaturated carboxylic acid unit or α,β-unsaturated carboxylic acid derivative unit bonded to the main chain of a modified polyolefin resin. Here, the configuration in which an α,β-unsaturated carboxylic acid unit or α,β-unsaturated carboxylic acid derivative unit is bonded alone to the main chain of a modified polyolefin resin is also called a single graft.

[0016] When α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units are further bonded to α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units already bonded to the main chain, a copolymer is obtained having poly(α,β-unsaturated carboxylic acid) blocks or poly(α,β-unsaturated carboxylic acid derivative) blocks as side chains. The peak of the stretching vibration of the carbonyl group in the poly(α,β-unsaturated carboxylic acid) block or poly(α,β-unsaturated carboxylic acid derivative) block, which is the side chain, is shifted to a lower wavenumber side than the peak of the stretching vibration of the carbonyl group in the single-graft α,β-unsaturated carboxylic acid unit or α,β-unsaturated carboxylic acid derivative unit, due to the influence of adjacent carbonyl groups. Here, the form in which a block, to which multiple α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units are bonded to the main chain of a modified polyolefin resin is also called a block graft.

[0017] The wavenumber at the peak of the peak identified as the stretching vibration of the carbonyl group is 1786.0 cm⁻¹. －１ 1795.0cm or more －１ The following means that in the modified polyolefin resin, there is a certain amount or more of single-grafted α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units.

[0018] When there are many singly-grafted α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units, it is considered that there are few poly(α,β-unsaturated carboxylic acid) blocks or poly(α,β-unsaturated carboxylic acid derivative) blocks formed by polymerizing a plurality of said monomer units grafted onto the modified polyolefin resin chain. Such a modified polyolefin resin is considered to have α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units uniformly or nearly uniformly grafted onto the main chain, and such a modified polyolefin resin can potentially form a crosslinked structure with high density. Therefore, if a crosslinked structure is formed after arranging a composition containing the modified polyolefin resin between members, it is considered that high adhesion can be exhibited even at high temperatures.

[0019] From the viewpoint of improving adhesion at high temperatures, the wave number at the peak apex is preferably 1786.0 cm －１ or higher, more preferably 1786.5 cm －１ or higher, still more preferably 1787.0 cm －１ or higher, even more preferably 1787.5 cm －１ or higher. The wave number at the peak apex is preferably 1795.0 cm －１ or lower, more preferably 1790.0 cm －１ or lower, still more preferably 1789.0 cm －１ or lower. In one embodiment, the wave number at the peak apex is preferably 1786.0 cm －１ or more and 1795.0 cm －１ or less, more preferably 1786.5 cm －１ or more and 1790.0 cm －１ or less, still more preferably 1787.0 cm －１ or more and 1789.0 cm －１ or less.

[0020] The wave number at the apex is 1786.0 cm －１ or more and 1795.0 cm －１Modified polyolefin resins having the following peaks can be produced by carrying out the modification reaction of the polyolefin resin under reaction conditions such that no further α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units are bonded to the single-grafted α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units. Examples of such reaction conditions include conditions under which the radical of the single-grafted α,β-unsaturated carboxylic acid or the radical of the α,β-unsaturated carboxylic acid derivative is transferred to another compound. Specifically, examples include carrying out the modification reaction in the presence of a chain transfer agent (thiol-based chain transfer agent); or carrying out the reaction in the presence of N-bromosuccinimide (NBS).

[0021] <Measurement Conditions for Fourier Transform Infrared Absorption Spectra> The measurement conditions for the Fourier transform infrared absorption spectrum may be as follows. First, a modified polyolefin resin is dissolved in an organic solvent to obtain a solution. For example, toluene can be used as the organic solvent. Next, the solution is applied to a KBr plate, then dried to form a thin film, and measured using an FT-IR measuring device (e.g., "FT / IR-4600", manufactured by JASCO Corporation) at 400 to 4000 cm⁻¹. －１ Observe the infrared absorption spectrum within the specified range. The number of integrations can be up to 16. The measurement resolution is 4 cm. －１ This is possible. The analysis can be performed using software included with the measuring device (e.g., "Spectro Manager," manufactured by JASCO Corporation).

[0022] <1.2. Polyolefin Resins> Polyolefin resins include olefin polymers. An olefin polymer refers to a polymer that contains structural units (olefin units) obtained by polymerizing olefins. Hereinafter, the olefin polymer contained in polyolefin resins will also be called olefin polymer (A). Here, the olefin is usually α-olefin. Examples of α-olefins include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene. Polyolefin resins may be used alone or in combination of two or more types. When two or more types are used in combination, the proportions are not particularly limited.

[0023] The olefin polymer (A) may be a polymer of a single olefin (generally an α-olefin), or may be a copolymer of two or more olefins (generally α-olefins). When the olefin polymer (A) is a copolymer, the olefin polymer may be a random copolymer or a block copolymer.

[0024] From the viewpoint of developing sufficient adhesiveness to non-polar resin substrates such as polypropylene substrates, polypropylene (homopropylene polymer), ethylene-propylene copolymer, propylene-1-butene copolymer, and ethylene-propylene-1-butene copolymer are preferable as the olefin polymer (A).

[0025] Here, the term "polypropylene" refers to a polymer whose constituent units are propylene-derived constituent units. The term "ethylene-propylene copolymer" refers to a copolymer containing ethylene-derived constituent units and propylene-derived constituent units as constituent units. The term "propylene-1-butene copolymer" refers to a copolymer containing propylene-derived constituent units and 1-butene-derived constituent units as constituent units. The term "ethylene-propylene-1-butene copolymer" refers to a copolymer containing ethylene-derived constituent units, propylene-derived constituent units and 1-butene-derived constituent units as constituent units. These polymers and copolymers may contain a small amount of other olefin-derived constituent units as constituent units, as long as the amount does not significantly impair the inherent performance of the polyolefin resin.

[0026] The olefin polymer (A) preferably contains 15 mol% or more of propylene-derived constituent units, more preferably 30 mol% or more, and even more preferably 50 mol% or more, based on 100 mol% of all constituent units. The upper limit is usually 100 mol% or less. When the olefin polymer (A) contains propylene-derived constituent units in the above range, the modified polyolefin resin can maintain adhesiveness to non-polar resin substrates such as polypropylene substrates.

[0027] When the olefin polymer (A) is an ethylene-propylene copolymer, a propylene-1-butene copolymer, or an ethylene-propylene-1-butene copolymer, of the total 100 mol% of the constituent units contained in the olefin polymer (A), the constituent units derived from ethylene and / or butene are preferably 3 to 85 mol%, more preferably 10 to 70 mol%, and the constituent units derived from propylene are preferably 15 to 97 mol%, more preferably 30 to 90 mol%.

[0028] In one embodiment, the olefin polymer (A) is preferably obtained using a metallocene catalyst as the polymerization catalyst. Known metallocene catalysts can be used. Using a metallocene catalyst narrows the molecular weight distribution of the olefin polymer (A). Furthermore, if the olefin polymer (A) is a copolymer, it exhibits excellent random copolymerization properties, a narrow compositional distribution, and a wider range of copolymerizable comonomers.

[0029] In one embodiment, the structure of the olefin polymer (A) may be an isotactic structure, an atactic structure, a syndiotactic structure, or any other structure. Among these structures, considering adhesion to the polyolefin substrate, the olefin polymer (A) having an isotactic structure, which can be adopted when a metallocene catalyst is used, is preferred.

[0030] The content of the olefin polymer (A) in the polyolefin resin is preferably 95% by weight or more, more preferably 98% by weight or more, even more preferably 99% by weight or more, and is usually 100% by weight or less, and may be 100% by weight.

[0031] The lower limit of the melting point of the polyolefin resin is preferably 30°C or higher, more preferably 60°C or higher, and the upper limit is preferably 180°C or lower, more preferably 170°C or lower, even more preferably 165°C or lower, and even more preferably 150°C or lower, 140°C or lower, 130°C or lower, or 120°C or lower. When the melting point of the polyolefin resin is 30°C or higher, when a coating film is formed using the modified polyolefin resin as an ink, paint, etc., sufficient coating film strength can be achieved. Therefore, the adhesion between the coating film of the modified polyolefin resin and the substrate can be fully exhibited. In addition, when used as an ink, blocking during printing can be suppressed. When the melting point of the polyolefin resin is 180°C or lower, when a coating film is formed using the modified polyolefin resin as an ink, paint, etc., excessive hardening of the coating film can be suppressed. Therefore, the coating film can exhibit appropriate flexibility.

[0032] The melting point of polyolefin resins and the melting point of modified polyolefin resins, as described later, can be measured using a differential scanning calorimetry (DSC) analyzer (e.g., "DISCOVERY DSC2500," manufactured by T.A. Instrument Japan Co., Ltd.). The measurement can be performed according to the following conditions: Approximately 5 mg of the sample is heated to 150°C for 5 minutes and held in a molten state. Then, the temperature is lowered at a rate of 10°C / min and held stably at -50°C for 5 minutes. After that, the temperature is further raised to 150°C at a rate of 10°C / min and the melting peak temperature is measured, and this temperature can be taken as the melting point (Tm).

[0033] The lower limit of the weight-average molecular weight (Mw) of the polyolefin resin is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 40,000 or more, and particularly preferably 50,000 or more. The upper limit is preferably 500,000 or less, more preferably 400,000 or less, even more preferably 300,000 or less, even more preferably 200,000 or less, even more preferably 170,000 or less, and particularly preferably 150,000 or less. The weight-average molecular weight (Mw) of the polyolefin resin and the modified polyolefin resin described later can be measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0034] <1.3. Modified Components> The modified components include one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives. The modified components may include only one selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, or two or more in any ratio.

[0035] Examples of α,β-unsaturated carboxylic acids include maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, aconitic acid, and (meth)acrylic acid.

[0036] Examples of derivatives of α,β-unsaturated carboxylic acids include α,β-unsaturated carboxylic acid anhydrides and α,β-unsaturated carboxylic acid esters.

[0037] Examples of α,β-unsaturated carboxylic acid anhydrides include α,β-unsaturated carboxylic acid cyclic anhydrides. Examples of α,β-unsaturated carboxylic acid cyclic anhydrides include maleic anhydride, citraconic anhydride, itaconic anhydride, and aconitic anhydride.

[0038] Examples of α,β-unsaturated carboxylic acid esters include (meth)acrylic acid esters. Examples of (meth)acrylic acid esters include alkyl (meth)acrylates. Preferred examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, 2,4,6-trimethylheptyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, and stearyl (meth)acrylate.

[0039] In one embodiment, the number of carbon atoms in the alkyl (meth)acrylate is preferably 1 to 30, more preferably 4 to 20, even more preferably 8 to 16, and particularly preferably 10 to 14. The modified component may not contain alkyl (meth)acrylate, may contain one type alone, or may contain two or more types in combination.

[0040] The modified component preferably comprises a derivative of an α,β-unsaturated carboxylic acid, more preferably an α,β-unsaturated carboxylic acid anhydride, even more preferably an α,β-unsaturated carboxylic acid cyclic anhydride, and particularly preferably maleic anhydride.

[0041] In another embodiment, the modified component preferably comprises a (meth)acrylic acid ester, and more preferably an alkyl (meth)acrylate.

[0042] In yet another embodiment, the modified component preferably comprises an α,β-unsaturated carboxylic acid anhydride (preferably maleic anhydride) and a (meth)acrylic acid ester, more preferably an α,β-unsaturated carboxylic acid cyclic anhydride and a (meth)acrylic acid ester, even more preferably maleic anhydride and a (meth)acrylic acid ester, and even more preferably maleic anhydride and an alkyl (meth)acrylate.

[0043] When the modified component contains an α,β-unsaturated carboxylic acid cyclic anhydride, the cyclic structure derived from the α,β-unsaturated carboxylic acid cyclic anhydride contained in the modified polyolefin resin may be partially hydrolyzed and ring-opened. Ring-opening by hydrolysis of the cyclic structure can result in a ring-opened structure that typically has two carboxyl groups.

[0044] The weight percentage of α,β-unsaturated carboxylic acids and their derivatives contained in the modified component is preferably 1% by weight or more, more preferably 2% by weight or more, even more preferably 3% by weight or more, preferably 20% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less, with the polyolefin resin being 100% by weight. Here, if the modified component contains two or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, the weight percentage of α,β-unsaturated carboxylic acids and their derivatives is the total weight percentage of α,β-unsaturated carboxylic acids and their derivatives.

[0045] When the modified component contains α,β-unsaturated carboxylic acid anhydrides (preferably α,β-unsaturated carboxylic acid cyclic anhydrides, more preferably maleic anhydride), the weight percentage of α,β-unsaturated carboxylic acid anhydrides is preferably 1% by weight or more, more preferably 2% by weight or more, even more preferably 3% by weight or more, preferably 20% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less, with the polyolefin resin being 100% by weight. Here, when the modified component contains two or more selected from the group consisting of α,β-unsaturated carboxylic acid anhydrides, the weight percentage of α,β-unsaturated carboxylic acid anhydrides is the total weight percentage of α,β-unsaturated carboxylic acid anhydrides.

[0046] When the modified component contains an α,β-unsaturated carboxylic acid anhydride (preferably an α,β-unsaturated carboxylic acid cyclic anhydride, more preferably maleic anhydride), with the total amount of the modified component being 100% by weight, the content of the α,β-unsaturated carboxylic acid anhydride is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 40% by weight or more, even more preferably 50% by weight or more, even more preferably 60% by weight or more, even more preferably 70% by weight or more, even more preferably 80% by weight or more, and even more preferably 90% by weight or more, and is usually 100% by weight or less, and may be 100% by weight.

[0047] When the modified component contains (meth)acrylic acid ester, the weight percentage of (meth)acrylic acid ester is preferably 1% by weight or more, more preferably 2% by weight or more, even more preferably 3% by weight or more, preferably 20% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less, with the polyolefin resin being 100% by weight.

[0048] When the modified component contains α,β-unsaturated carboxylic acid anhydride (preferably α,β-unsaturated carboxylic acid cyclic anhydride, more preferably maleic anhydride) and (meth)acrylic acid ester, the weight ratio of α,β-unsaturated carboxylic acid anhydride to (meth)acrylic acid ester in the modified component (α,β-unsaturated carboxylic acid anhydride / (meth)acrylic acid ester) is preferably 10 / 90 or more, more preferably 30 / 70 or more, even more preferably 40 / 60 or more, preferably 90 / 10 or less, more preferably 70 / 30 or less, and even more preferably 60 / 40 or less.

[0049] The weight ratio of the total weight of the modified component to the weight of the polyolefin resin is preferably 1% by weight or more, more preferably 2% by weight or more, even more preferably 3% by weight or more, preferably 20% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less, with the polyolefin resin being 100% by weight. Here, the total weight of the modified component means the weight of that one compound if the modified component consists of only one compound.

[0050] The modified polyolefin resin may be modified with any additional modifying component in addition to the aforementioned modifying component.

[0051] For example, modified polyolefin resin may be modified with chlorine. Hereafter, modification with chlorine will also be referred to as chlorination.

[0052] Chlorination can be carried out by a method that further introduces chlorine into the resin to be chlorinated. For chlorine introduction, the resin to be chlorinated may be pre-dissolved in a chlorine-based solvent such as chloroform. Chlorine is usually introduced by blowing chlorine gas into the reaction system. Chlorine gas may be blown in under ultraviolet irradiation, or in the presence or absence of a radical reaction initiator. The pressure during chlorine gas blowing is not limited and may be at atmospheric pressure or under pressurized pressure. The temperature during chlorine gas blowing is not particularly limited, but is usually 50 to 140°C. As the radical reaction initiator, known agents usable for chlorination can be used, and specific examples include organic peroxides and azonitriles, which will be described later. The amount of radical reaction initiator used in chlorination is preferably 0.001% to 1% by weight, more preferably 0.01% to 0.1% by weight, based on 100% by weight of the raw material resin. After chlorine is introduced, the chlorinated solvent in the system is usually removed by distillation under reduced pressure or replaced with an organic solvent.

[0053] The degree of chlorination of a modified polyolefin resin represents the chlorine content (amount of chlorine grafted) with the modified polyolefin resin after chlorination being 100% by weight. The degree of chlorination is preferably 17% by weight or more, more preferably 18% by weight or more, and even more preferably 19% by weight or more or 20% by weight or more. The upper limit is preferably 23% by weight or less, more preferably 22% by weight or less. The degree of chlorination can be measured according to JIS-K7229. That is, it can be measured using the "oxygen flask combustion method," in which the chlorinated resin is burned in an oxygen atmosphere, the generated gaseous chlorine is absorbed with water, and quantified by titration. The degree of chlorination can be adjusted, for example, by the type of polyolefin resin, the scale of the chlorination reaction, the reaction apparatus used for chlorination, the amount of chlorine gas blown in, and the time.

[0054] When chlorination modification is performed, the order of modification with the modification component and chlorination modification is not particularly limited. Therefore, the modified polyolefin resin may be a resin obtained by chlorinating a polyolefin resin modified with the modification component, or a resin obtained by modifying a chlorinated polyolefin resin with the modification component.

[0055] <1.4. Modified Polyolefin Resin> From the viewpoint of effectively improving the adhesion of modified polyolefin resin at high temperatures, the total graft weight (degree of modification) of the modified component in the modified polyolefin resin is preferably 50% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, and particularly preferably 10% by weight or less, with no particular limit on the lower limit, but preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 1% by weight or more, even more preferably 2% by weight or more, and particularly preferably 3% by weight or more. The total graft weight (by weight %) of the modified component can be determined, for example, by alkaline titration, Fourier transform infrared spectroscopy, or １ This can be determined by H-NMR.

[0056] When the modified component contains α,β-unsaturated carboxylic acid anhydride, from the viewpoint of effectively improving the adhesion of the modified polyolefin resin at high temperatures, the graft weight of α,β-unsaturated carboxylic acid anhydride in the modified polyolefin resin is preferably 50% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, and particularly preferably 10% by weight or less, with no lower limit being particularly limited, but preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 1% by weight or more, even more preferably 2% by weight or more, and particularly preferably 3% by weight or more. The graft weight (by weight %) of α,β-unsaturated carboxylic acid anhydride can be determined, for example, by alkaline titration, Fourier transform infrared spectroscopy, or １ This can be determined by H-NMR.

[0057] When the modified component contains α,β-unsaturated carboxylic acid esters, from the viewpoint of effectively improving the adhesion of the modified polyolefin resin at high temperatures, the graft weight of α,β-unsaturated carboxylic acid esters in the modified polyolefin resin is preferably 50% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, and particularly preferably 10% by weight or less, with no particular limit on the lower limit, but preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 1% by weight or more, even more preferably 2% by weight or more, and particularly preferably 3% by weight or more. The graft weight (by weight %) of α,β-unsaturated carboxylic acid esters can be determined, for example, by alkaline titration, Fourier transform infrared spectroscopy, or １ This can be determined by H-NMR.

[0058] The content ratio of the modified polyolefin resin by the modifying component in the modified polyolefin resin is preferably 50% by weight or more, more preferably 70% by weight or more, even more preferably 80% by weight or more, and even more preferably 90% by weight or more, and is usually 100% by weight or less, and may be 100% by weight, or 99% by weight or less, 98% by weight or less, 97% by weight or less, or 95% by weight or less. In addition to the modified polyolefin resin by the modifying component, the modified polyolefin resin may contain optional components to the extent that they do not significantly reduce the effects of the present invention.

[0059] Modified polyolefin resins may contain chain transfer agents. A chain transfer agent is a compound that can be added to a chain reaction system to promote a chain transfer reaction. The chain transfer agent may be included in the modified polyolefin as the added compound itself, or as a product containing a structure derived from the chain transfer agent. Here, a product containing a structure derived from the chain transfer agent is a compound having at least a part of the structure of the chain transfer agent, and may contain structures other than the structure of the chain transfer agent, and may be a low molecular weight compound, or a high molecular weight compound such as an oligomer or polymer. When a polyolefin resin is modified with a modifying component, the chain transfer agent is added to the reaction system and may remain in the modified polyolefin resin either in the form of the chain transfer agent itself or as a product having at least a part of the structure of the chain transfer agent.

[0060] The presence of chain transfer agents in modified polyolefin resins can be confirmed, for example, by gas chromatography analysis.

[0061] When a modified polyolefin resin contains a chain transfer agent, the content of the chain transfer agent in the modified polyolefin resin is usually 0% by weight or more, may be 0% by weight or more, preferably 1% by weight or more, more preferably 2% by weight or more, preferably 5% by weight or less, more preferably 4% by weight or less, and even more preferably 3% by weight or less, with the polyolefin resin being 100% by weight. Typically, the content of the chain transfer agent in the modified polyolefin resin, with the polyolefin resin being 100% by weight, is the same as the weight ratio of the chain transfer agent used in the production of the modified polyolefin resin to the polyolefin resin. By adding a chain transfer agent to the modification reaction system in an amount such that the chain transfer agent is contained in the modified polyolefin resin within the above range, a modified polyolefin resin with effectively improved adhesion at high temperatures can be obtained.

[0062] The modified polyolefin resin may contain a single chain transfer agent or a combination of two or more chain transfer agents.

[0063] The chain transfer agent preferably has an aliphatic hydrocarbon group having 5 or more carbon atoms. The aliphatic hydrocarbon group having 5 or more carbon atoms has low polarity and high affinity with low-polarity olefin polymers. Therefore, the chain transfer agent can be well mixed with polyolefin resins. The chain transfer agent having an aliphatic hydrocarbon group having 5 or more carbon atoms may be a thiol-based chain transfer agent as described later.

[0064] Aliphatic hydrocarbon groups having 5 or more carbon atoms may be linear or branched. Aliphatic hydrocarbon groups having 5 or more carbon atoms may be monovalent or divalent or more (for example, divalent), and are preferably monovalent. The upper limit of the number of carbon atoms in an aliphatic hydrocarbon group having 5 or more carbon atoms may be, for example, 20 or less, or for example, 18 or less.

[0065] Examples of aliphatic hydrocarbon groups having five or more carbon atoms include pentyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, tridecyl group, hexadecyl group, and octadecyl group.

[0066] Examples of chain transfer agents include thiol-based chain transfer agents, which are preferred from the viewpoint of effectively improving the adhesion of modified polyolefin resins at high temperatures. A thiol-based chain transfer agent is a chain transfer agent having a thiol group in its molecule. Thiol-based chain transfer agents may be monofunctional or polyfunctional.

[0067] Examples of thiol chain transfer agents include β-mercaptopropionic acid, β-mercaptopropionic acid esters (e.g., 2-ethylhexyl-3-mercaptopropionate, methoxybutyl-β-mercaptopropionate, pentaerythritol tetra(3-mercaptopropionate): also known as 2,2-bis[[(3-mercaptopropionyl)oxy]methyl]trimethylenebis[3-mercaptopropionate]), 1,4-bis(3-mercaptobutyryloxy)butane, tris(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptobutyrate), trimethylolpropane tris(3-mercap Examples include mercapto group-substituted carboxylic acid esters such as tobutylate; aliphatic alkylthiols such as 1-butanethiol, 1-octanthiol, and 1-dodecanethiol; cyclic alkylthiols such as cyclohexyl mercaptan; aromatic thiols such as thiophenol; polyfunctional thiols such as 2,2-bis[[(3-mercaptopropionyl)oxy]methyl]trimethylenebis[3-mercaptopropionate]; and secondary thiols such as 1,4-bis(3-mercaptobutyryloxy)butane and 1,3,5-tris(2-(3-sulfanylbutanoyloxy)ethyl)-1,3,5-triazinan-2,4,6-trione.

[0068] The chain transfer agent that may be included in the modified polyolefin resin is preferably one or more selected from the group consisting of aliphatic alkylthiols and mercapto group-substituted carboxylic acid esters, and more preferably one or more selected from the group consisting of 1-dodecanethiol and 2-ethylhexyl 3-mercaptopropionate.

[0069] Other examples of optional components that may be included in modified polyolefin resins include polymerization initiators.

[0070] Modified polyolefin resins may contain solvents, but the weight percentage of solvents in the modified polyolefin resin is preferably 10% by weight or less, more preferably 15% by weight or less, and even more preferably 5% by weight or less, with the modified polyolefin resin being 100% by weight. It is usually 0% by weight or more, and may contain no solvent (i.e., 0% by weight) or more than 0% by weight. Such modified polyolefin resins with a low solvent content can be produced, for example, by heating and kneading the polyolefin resin and modified components in a reaction apparatus such as an extruder.

[0071] From the viewpoint of effectively improving the adhesion of modified polyolefin resins at high temperatures, the lower limit of the weight-average molecular weight (Mw) of the modified polyolefin resin is preferably 10,000 or more, more preferably 30,000 or more, and even more preferably 50,000 or more, and the upper limit is preferably 200,000 or less, more preferably 180,000 or less, and even more preferably 150,000 or less.

[0072] From the viewpoint of effectively improving the adhesion of the modified polyolefin resin at high temperatures, the lower limit of the melting point of the modified polyolefin resin is preferably 50°C or higher, more preferably 60°C or higher, and even more preferably 65°C or higher, and the upper limit is preferably 80°C or lower, more preferably 75°C or lower, and even more preferably less than 75°C.

[0073] <1.5. Method for Producing Modified Polyolefin Resin> The above-mentioned modified polyolefin resin can be produced by any method. The modified polyolefin resin can be produced by either the solution method or the melting method. The solution method is a method in which the modification reaction of the polyolefin resin by the modification component is carried out in the form of a solution of the polyolefin resin in a solvent. The melting method is a method in which the modification reaction of the polyolefin resin by the modification component is carried out in the form of a melted polyolefin resin in the absence of a solvent or in the presence of a small amount of solvent. From the viewpoint of effectively obtaining the advantages of the present invention, it is preferable that the modified polyolefin resin is produced by the melting method.

[0074] Modified polyolefin resins can preferably be produced by a method comprising the following steps (a): (a) Heating a composition comprising the polyolefin resin, a chain transfer agent, and the modified component. The modified component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives.

[0075] Here, the heating in step (a) is usually carried out at a temperature of 150°C to 190°C.

[0076] The heating in step (a) is preferably 150°C or higher, more preferably 155°C or higher, even more preferably 160°C or higher, even more preferably above 160°C, and even more preferably 170°C or higher, from the viewpoint of facilitating the mixing of the composition and promoting the decomposition of the initiator, and preferably 190°C or lower, more preferably 185°C or lower, even more preferably 180°C or lower, and even more preferably below 180°C, from the viewpoint of reducing the decomposition of the modified polyolefin resin.

[0077] The composition heated in step (a) comprises the polyolefin resin, the chain transfer agent, and the modified component. Hereinafter, the composition heated in step (a) will also be referred to as composition (C1). Composition (C1) preferably contains no solvent or contains only a small amount of solvent. The weight percentage of the solvent in composition (C1) is preferably 1% by weight or less, more preferably 0.5% by weight or less, and even more preferably 0.1% by weight or less, with the weight percentage of composition (C1) being 100% by weight, and is usually 0% by weight or greater than 0% by weight, may be 0% by weight, or 0.05% by weight or more.

[0078] The chain transfer agent contained in composition (C1) may be the same as the chain transfer agent that may be optionally included in the modified polyolefin resin. By including the chain transfer agent in composition (C1), the number of α,β-unsaturated carboxylic acid units or α,β-unsaturated carboxylic acid derivative units that are individually bonded to the main chain of the modified polyolefin resin can be increased, thereby enabling a uniform or nearly uniform graft of the modified component. As a result, the modified polyolefin resin can exhibit high adhesion at high temperatures.

[0079] Examples and preferred examples of chain transfer agents included in composition (C1) include examples and preferred examples of chain transfer agents that may be included in the modified polyolefin resin. In one embodiment, composition (C1) preferably includes a thiol-based chain transfer agent as the chain transfer agent.

[0080] From the viewpoint of obtaining a modified polyolefin resin with effectively improved adhesion at high temperatures, the weight percentage of the chain transfer agent contained in composition (C1) is usually greater than 0% by weight, preferably 1% or more by weight, more preferably 2% or more by weight, preferably 5% or less by weight, more preferably 4% or less by weight, and even more preferably 3% or less by weight, with the weight of the polyolefin resin contained in composition (C1) being 100% by weight. In one embodiment, composition (C1) preferably contains the polyolefin resin, a thiol-based chain transfer agent, and a modified component, and the content of the thiol-based chain transfer agent in composition (C1) is preferably 2% or more by weight, preferably 5% or less by weight, more preferably 4% or less by weight, and even more preferably 3% or less by weight, with respect to 100% by weight of the polyolefin resin. In one embodiment, the content of the thiol-based chain transfer agent in composition (C1) is preferably 2 to 5% by weight, more preferably 3 to 5% by weight.

[0081] Examples and preferred examples of polyolefin resins and examples and preferred examples of modified components included in composition (C1) are those described in the section on modified polyolefin resins.

[0082] The total weight percentage of the polyolefin resin, chain transfer agent, and modifying component in composition (C1) is preferably 70% by weight or more, more preferably 80% by weight or more, and even more preferably 90% by weight or more, with an upper limit of usually 100% by weight or less, which may be 100% by weight or 99% by weight or less. In addition to the polyolefin resin, chain transfer agent, and modifying component, composition (C1) may contain optional components. An example of an optional component is a radical reaction initiator. Composition (C1) preferably contains a radical reaction initiator, and it is preferable that the modification of the polyolefin resin by the modifying component is carried out in the presence of the radical reaction initiator.

[0083] Examples of radical reaction initiators include thermal polymerization initiators that generate free radicals when heated, and examples of thermal polymerization initiators include organic peroxides and azonitriles.

[0084] Examples of organic peroxides include di-tert-butyl peroxide, dicumyl peroxide, tert-butylcumyl peroxide, dibenzoyl peroxide, benzoyl m-tolyl peroxide, di(m-tolyl)benzoyl, dilauryl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, cumene hydroperoxide, tert-butyl hydroperoxide, and 1,1-bis(tert-butylperoxy)- Examples include 3,5,5-trimethylcyclohexane, 1,1-bis(tert-butylperoxy)-cyclohexane, cyclohexanone peroxide, tert-butylperoxybenzoate, tert-butylperoxyisobutyrate, tert-butylperoxy-3,5,5-trimethylhexanoate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyisopropyl carbonate, and cumylperoxyoctoate.

[0085] Examples of azonitriles include 2,2-azobis(2-methylbutyronitrile), 2,2-azobisisobutyronitrile, 2,2-azobis(2,4-dimethylvaleronitrile), and 2,2-azobis(4-methoxy-2,4-dimethylvaleronitrile).

[0086] If composition (C1) contains a radical reaction initiator, the amount of the radical reaction initiator is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 1.0% by weight or more, preferably 10% by weight or less, more preferably 5% by weight or less, even more preferably 3% by weight or less, preferably 0.01% to 10% by weight, and even more preferably 0.1% to 5% by weight, based on 100% by weight of the raw material polyolefin resin.

[0087] The heating in step (a) may be carried out in a device such as a Banbury mixer, kneader, or extruder, and from the viewpoint of efficiently and continuously producing modified polyolefin resin, it is preferable to carry it out in an extruder. Examples of extruders include single-screw extruders and twin-screw extruders.

[0088] When the heating in step (a) is performed inside the extruder, the heating temperature can be adjusted by adjusting the temperature of the barrels provided in the extruder. If the extruder has multiple barrels, the temperature of all of the multiple barrels may be adjusted to the heating temperature range, or the temperature of some of the barrels may be adjusted to the heating temperature range.

[0089] The introduction of the modified components into the extruder may be done all at once or in stages.

[0090] The method for producing a modified polyolefin resin may include any additional steps in addition to step (a) described above. An example of an optional step is the step of chlorinating the resin. The material to be chlorinated may be a modified polyolefin resin or a regular polyolefin resin.

[0091] <1.6. Forms of Modified Polyolefin Resins, Modified Polyolefin Resin Compositions> Modified polyolefin resins can be used in various forms. For example, they can be used in various applications as modified polyolefin resin compositions, which are in the form of solutions (e.g., resin solutions, aqueous dispersions) or solids (e.g., pellets) containing the modified polyolefin resin.

[0092] The modified polyolefin resin composition may optionally contain additives such as solvents, curing agents, adhesive components, basic substances, emulsifiers, crosslinking agents, diluents, light stabilizers, UV absorbers, pigments, dyes, and inorganic fillers.

[0093] The modified polyolefin resin composition may be a resin solution containing an organic solvent. Examples of organic solvents include aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as methyl ethyl ketone and methyl butyl ketone; alicyclic hydrocarbon solvents such as cyclohexane, methylcyclohexane, and ethylcyclohexane; and aliphatic hydrocarbon solvents such as nonane and decane. The resin solution may contain one organic solvent alone or two or more in any combination of proportions. From the viewpoint of reducing the burden on the environment, organic solvents other than aromatic solvents are preferred, and mixed solvents of alicyclic hydrocarbon solvents and ester solvents or ketone solvents are more preferred.

[0094] The weight percentage of the organic solvent in the resin solution is preferably 10% by weight or more, more preferably 30% by weight or more, preferably 95% by weight or less, and more preferably 90% by weight or less, with the modified polyolefin resin being 100% by weight.

[0095] The modified polyolefin resin composition may be an aqueous dispersion. The aqueous dispersion may contain a hydrophilic solvent. The hydrophilic solvent is preferably a solvent that is miscible with water in any proportion.

[0096] Examples of hydrophilic solvents include water; glycol-based solvents such as ethylene glycol; alcohol-based solvents such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and 2-ethylhexanol; and glycol monoether-based solvents such as ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monoisopropyl ether, and propylene glycol monobutyl ether. Solvents may be used individually or in combination of two or more types.

[0097] The weight percentage of the hydrophilic solvent in the aqueous dispersion is not particularly limited. For example, the weight percentage of the hydrophilic solvent is preferably such that the solid content concentration of the modified polyolefin resin is 10 to 50% by weight, and more preferably 20 to 40% by weight.

[0098] When a hydrophilic solvent is used as the solvent, the resin composition preferably contains an emulsifier. Examples of emulsifiers include surfactants such as nonionic surfactants, anionic surfactants, and cationic surfactants. Among these, nonionic surfactants are preferred.

[0099] Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene derivatives, polyoxyethylene fatty acid esters, polyoxyethylene polyhydric alcohol fatty acid esters, polyoxyethylene polyoxypropylene polyols, sorbitan fatty acid esters, polyoxyethylene hydrogenated castor oil, polyoxyalkylene polycyclic phenyl ethers, polyoxyethylene alkylamines, alkyl alkanolamides, and polyalkylene glycol (meth)acrylates. Preferably, these are polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and polyoxyethylene alkylamines.

[0100] Examples of anionic surfactants include alkyl sulfates, polyoxyethylene alkyl ether sulfates, alkylbenzene sulfons, α-olefin sulfons, methyl tauryl salts, sulfosuccinates, ether sulfons, ether carboxylates, fatty acid salts, and naphthalene sulfonic acid formalin condensates. Preferably, polyoxyethylene alkyl ether sulfates and sulfosuccinates are used.

[0101] Examples of cationic surfactants include alkylamine salts and quaternary ammonium salts.

[0102] Examples of amphoteric surfactants include alkyl betaines and alkylamine oxides.

[0103] Emulsifiers may be used individually or in combination of two or more types.

[0104] The aqueous dispersion containing the modified polyolefin resin may further contain a neutralizing agent. This can further improve the dispersibility of the resin in hydrophilic solvents. Examples of neutralizing agents include ammonia, methylamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, isobutylamine, hexylamine, octylamine, ethanolamine, propanolamine, diethanolamine, N-methyldiethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dibutylethanolamine, 2-dimethylamino-2-methyl-1-propanol, 2-amino-2-methyl-1-propanol, 2-aminoethanol, 2-dimethylaminoethanol, 2-diethylaminoethanol, 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, n-butylamine, 2-methoxyethylamine, 3-methoxypropylamine, 2,2-dimethoxyethylamine, morpholine, N-methylmorpholine, N-ethylmorpholine, piperazines, pyrrole, pyridine, sodium hydroxide, potassium hydroxide, magnesium hydroxide, and other metal hydroxides. In particular, morpholine, N,N-dimethylethanolamine, N,N-diethylethanolamine, and 2-amino-2-methyl-1-propanol are preferred from the viewpoint of ease of emulsification and dispersion.

[0105] The neutralizing agent may be used alone or in any combination of two or more agents in any ratio.

[0106] The modified polyolefin resin composition may contain a curing agent. Examples of curing agents include polyisocyanate compounds (e.g., hexamethylene diisocyanate (HDI) isocyanurate), epoxy compounds, polyamine compounds, polyol compounds, or crosslinking agents in which their functional groups are blocked by protecting groups. When a curing agent is used, a catalyst such as an organotin compound or a tertiary amine compound may be used in combination, depending on the purpose. The curing agent may be used alone or in combination of multiple types.

[0107] When the modified polyolefin resin composition contains a curing agent, the weight ratio of the curing agent is preferably 0.1 parts by weight or more, more preferably 0.2 parts by weight or more, even more preferably 0.25 parts by weight or more, even more preferably 1 part by weight or more, and even more preferably 10 parts by weight or more, with respect to 100 parts by weight of the modified polyolefin resin contained in the modified polyolefin resin composition.

[0108] Modified polyolefin resins can function as adhesive components. Modified polyolefin resin compositions may use known adhesive components such as polyester adhesives, polyurethane adhesives, and acrylic adhesives, as long as they do not hinder the desired effect. In one embodiment, the weight percentage of modified polyolefin resin when the total amount of adhesive components in the modified polyolefin resin composition is 100% by weight is preferably 80% by weight or more, more preferably 90% by weight or more, even more preferably 95% by weight or more, even more preferably 98% by weight or more, usually 100% by weight or less, and may be 100% by weight.

[0109] <1.7. Uses of Modified Polyolefin Resin> The modified polyolefin resin of this embodiment has excellent adhesion at high temperatures and can therefore be suitably used as a primer, adhesive (for example, an adhesive in laminate films such as aluminum laminate films), paint, or ink raw material. Accordingly, a modified polyolefin resin composition containing the modified polyolefin resin and any components included depending on the application can be used as a primer, adhesive, paint, or ink.

[0110] The present invention will be described in detail below using examples, but the present invention is not limited to these examples. Unless otherwise specified, the unit "parts" used below means "parts by weight," and the unit "%" means "weight percent." Unless otherwise specified, the temperature conditions in the following description are at room temperature (25°C), and the pressure conditions are at normal pressure (760 mmHg) unless otherwise specified.

[0111] <Measurement and Evaluation Methods> (Weight-Average Molecular Weight Mw) The weight-average molecular weight Mw of the modified polyolefin resin and polyolefin resin (polymer) used in the examples and comparative examples was measured by GPC using tetrahydrofuran as the eluent and polystyrene as the standard substance. In particular, the GPC conditions for the modified polyolefin resin were as follows. Measuring instrument: HLC-8420GPC (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran column: TSK-gel SuperH-6000, SuperH-5000, SuperH-4000, SuperH-3000, SuperH-2000, SuperHRC (manufactured by Tosoh Corporation) Standard substance: Polystyrene EasiCal PS-1 (manufactured by Agilent Technologies, Inc.) Detector: Differential refractometer (manufactured by Tosoh Corporation) Temperature: 40°C Injection volume: 20 μL Flow rate: 0.6 mL / min

[0112] (Melting Point (°C)) The melting point of the modified polyolefin resin was measured by the following method. Using a differential scanning calorimetry (DSC) analyzer (e.g., "DISCOVERY DSC2500", manufactured by T.A. Instruments Japan Co., Ltd.), approximately 5 mg of the sample was heated to 150°C for 5 minutes and held in a molten state. The temperature was then lowered at a rate of 10°C / min and held stably at -50°C for 5 minutes. After that, the temperature was further raised to 150°C at a rate of 10°C / min and the peak melting temperature was measured, and this temperature was defined as the melting point (Tm).

[0113] (Graft weight of maleic anhydride (wt%)) The graft weight of maleic anhydride in modified polyolefin resin was measured by alkaline titration. Specifically, it was measured as follows: Approximately 0.5 g of accurately weighed modified polyolefin resin and approximately 100 g of toluene were placed in a flask equipped with a condenser and thermometer, and dissolved by stirring while heating to an internal temperature of 80°C. After the resin was dissolved, 15 ml of methanol was added and held for 5 minutes, then 5 to 6 drops of indicator (1% phenolphthalein-methanol solution) were added, and the mixture was titrated with 0.1 mol / L potassium hydroxide-methanol solution. From the amount of titration required for neutralization, the graft weight (wt%) of maleic anhydride in the modified polyolefin resin was calculated using the following formula. K (weight %) = {B × f × 0.1 × F / (S × 1000)} × 100 Here, K represents the graft weight (weight %) of maleic anhydride with 100% weight of modified polyolefin resin, B represents the titration volume (ml) of potassium hydroxide-methanol solution, f represents the factor of 0.1 mol / L potassium hydroxide-methanol solution, F is the formula weight of maleic anhydride (98.06), and S represents the weight (g) of modified polyolefin resin.

[0114] (Fourier transform infrared absorption (FT-IR) measurement of modified polyolefin resin: Carbonyl C=O stretching vibration peak wavenumber (cm) －１ FT-IR measurements of modified polyolefin resin were performed as follows: First, the modified polyolefin resin was dissolved in an organic solvent to obtain a solution. Next, the solution was applied to a KBr plate, then dried to form a thin film, and measured using an FT-IR measuring device (e.g., "FT / IR-4600", manufactured by JASCO Corporation) at 400-4000 cm². －１ Infrared absorption spectra were observed in the range. Analysis was performed using the accompanying software (e.g., "Spectro Manager," manufactured by JASCO Corporation). The wavenumber range of 1750–1800 cm⁻¹ is identified as carbonyl stretching vibration. －１ The wavenumber WN at the peak of the peak appearing in the range was obtained.

[0115] (Heat-resistant adhesion evaluation 1: Laminator adhesive strength) 10 g of a modified polyolefin resin solution (solids content: 15%, solvent composition: methylcyclohexane / MEK = 80 / 20 (w / w)) was mixed with HDI isocyanurate (solids content 100%, NCO content 20%) as a curing agent in the amount shown in Table 1 to obtain an adhesive containing modified polyolefin resin. The obtained adhesive was applied to aluminum foil using a #16 to #20 Meyer bar to form a coating film on the aluminum foil. The coating film was then dried in a constant-temperature dryer set to 100°C. An unoriented polypropylene (CPP) sheet was prepared, and the unoriented polypropylene (CPP) sheet and the aluminum foil were layered and bonded together so that the dried coating film was placed in between. Then, heat-pressure bonding was performed using a laminator under the conditions of 100°C, 0.3 MPa, and peripheral speed of 1 m / min. Next, the material was aged for more than three days in a constant-temperature dryer set to 60°C. Then, the laminate was cut into 15 mm wide pieces to prepare test specimens, and the peel strength (laminate) was measured under conditions of a peel angle of 180°, a peel speed of 100 mm / min, and a 120°C atmosphere.

[0116] (Heat-resistant adhesion evaluation 2: Heat sealer adhesive strength) A resin composition for use as an adhesive containing modified polyolefin resin was obtained by mixing 10 g of a solution of modified polyolefin resin (solids content: 15%, solvent composition: methylcyclohexane / methyl ethyl ketone (MEK) = 80 / 20 (w / w)) with HDI isocyanurate (solids content 100%, NCO content 20%) as a curing agent in the amounts listed in Table 1. The amount of curing agent added was 17.3 parts by weight per 100 parts by weight of modified polyolefin resin in Examples 1 to 4 and Comparative Examples 1 to 2 and 5, and 34 parts by weight per 100 parts by weight of modified polyolefin resin in Comparative Examples 3 and 4. The obtained adhesive was applied to aluminum foil using a #16 to #20 Meyer bar to form a coating film on the aluminum foil with a film thickness of 5 μm after drying. The coating film was then dried in a constant temperature dryer set to 100°C. An unoriented polypropylene (CPP) sheet was prepared, and the CPP sheet and aluminum foil were layered and laminated so that the dried coating film was placed in between. Then, the sheets were bonded at a temperature of 200°C and a pressure of 3 kgf / cm². ２ The bonded parts were heat-sealed using a heat sealer under the condition of a time of 1 second. Subsequently, they were aged for more than 3 days in a constant temperature drying oven heated to 60°C. Then, the bonded parts were cut to a width of 15 mm to prepare test pieces, and the peel strength (heat seal) was measured under the conditions of a peel angle of 180°, a peel speed of 100 mm / min, and an atmosphere of 120°C.

[0117] <Example 1> 100 parts of a propylene-butene copolymer (Tm = 77°C, propylene component: 70 mol%, butene component: 30 mol%, Mw: 290,000) as a polyolefin resin containing an olefin polymer, 4 parts of maleic anhydride, which is a modifying component and an α,β-unsaturated carboxylic acid cyclic anhydride, 2 parts of 2-ethylhexyl 3-mercaptopropionate as a chain transfer agent, and 1.5 parts of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane as a radical reaction initiator were kneaded in a twin-screw extruder set to a reaction temperature of 170°C and the reaction was carried out. After the reaction, the kneaded mixture was cooled to room temperature to obtain a modified polyolefin resin. The obtained modified polyolefin resin was analyzed by the method described above to determine the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm). －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0118] <Examples 2-4> The chain transfer agent and the amount added were the compounds and amounts listed in Table 1, respectively. Otherwise, the procedure was the same as in Example 1 to obtain a modified polyolefin resin. For the obtained modified polyolefin resin, the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm) were determined by the method described above. －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0119] <Comparative Example 1> No chain transfer agent was added. Otherwise, the procedure was the same as in Example 1 to obtain a modified polyolefin resin. For the obtained modified polyolefin resin, the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm) were determined by the method described above. －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0120] <Comparative Example 2> 100 parts of a propylene-butene copolymer (Tm = 88°C) as a polyolefin resin containing an olefin polymer, 4 parts of maleic anhydride, which is a modifying component and an α,β-unsaturated carboxylic acid cyclic anhydride, 3 parts of lauryl methacrylate, which is a modifying component and an (meth)acrylic acid ester, and 1.5 parts of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane as a radical reaction initiator were kneaded in a twin-screw extruder set to a reaction temperature of 170°C and the reaction was carried out. After the reaction, the kneaded mixture was cooled to room temperature to obtain a modified polyolefin resin. The obtained modified polyolefin resin was then analyzed by the method described above to determine the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm). －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0121] <Comparative Example 3> 100 parts of a propylene-butene copolymer (Tm = 77°C, propylene component: 70 mol%, butene component: 30 mol%, Mw: 290,000) as a polyolefin resin containing an olefin polymer, 5.5 parts of maleic anhydride, which is a modifying component and an α,β-unsaturated carboxylic acid cyclic anhydride, 0.38 parts of α-methylstyrene dimer as a chain transfer agent, and 1.5 parts of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane as a radical reaction initiator were kneaded in a twin-screw extruder set to a reaction temperature of 170°C to carry out the reaction. After the reaction, the kneaded mixture was cooled to room temperature to obtain a modified polyolefin resin. The obtained modified polyolefin resin was analyzed by the above method to determine the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm). －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0122] <Comparative Example 4> The chain transfer agent and the amount of its addition were the compounds and amounts listed in Table 1, and the reaction temperature was 200°C. Otherwise, the procedure was the same as in Comparative Example 3 to obtain a modified polyolefin resin. The obtained modified polyolefin resin was analyzed by the method described above to determine the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm). －１The heat resistance and adhesion properties were evaluated by measuring the following:

[0123] <Comparative Example 5> 100 parts of propylene-butene copolymer (Tm = 77°C) as a polyolefin resin containing an olefin polymer, 20 parts of maleic anhydride, which is a modifying component and an α,β-unsaturated carboxylic acid cyclic anhydride, and 82.5 parts of xylene were charged into a flask. After raising the internal temperature to 140°C, 6.0 parts of di-t-butyl peroxide, as a radical reaction initiator, was diluted with 44 parts of xylene and added gradually over 2 hours, and the reaction was maintained at a 50% concentration for 4 hours. Then, the reaction solution was added dropwise into a methyl ethyl ketone solution to precipitate the polymer. The obtained precipitate was washed by stirring in methyl ethyl ketone, and then vacuum dried at 140°C for 2 hours or more to obtain an acid-modified polypropylene resin. For the obtained modified polyolefin resin, the weight of maleic anhydride graft (degree of maleization, wt%), weight-average molecular weight Mw, melting point Tm (°C), and wavenumber WN (cm) were determined by the method described above. －１ The heat resistance and adhesion properties were evaluated by measuring the following:

[0124] <Results> The results, along with the raw material formulations, are shown in Table 1. The abbreviations in Table 1 have the following meanings: Degree of maleization: Weight (wt%) of maleic anhydride graft in the modified polyolefin resin Mw: Weight-average molecular weight of the modified polyolefin resin Tm: Melting point (°C) of the modified polyolefin resin WN: Wavenumber 1750–1800 cm, identified as the carbonyl stretching vibration measured for the modified polyolefin resin －１ The wavenumber (cm) at the peak of the peak appearing in the range －１ ) EHMP: 2-ethylhexyl 3-mercaptopropionate DT: 1-dodecanethiol αMSD: α-methylstyrene dimer (also known as: 2,4-diphenyl-4-methyl-1-pentene) Laminate: Heat resistance and adhesion evaluation 1 Heat seal: Heat resistance and adhesion evaluation 2 *1: Evaluation not performed Also, the amount of curing agent added represents the amount of curing agent added per 10 g of the modified polyolefin resin solution.

[0125]

[0126] WN is 1786cm. 0 －１1795.0cm or more －１ The modified polyolefin resin according to the following examples exhibits excellent peel strength. The modified polyolefin resin according to the examples in which the kneaded composition contains 2-ethylhexyl 3-mercaptopropionate or 1-dodecanethiol as a thiol-based chain transfer agent exhibits excellent peel strength. In particular, Examples 1 and 2, which use 2-ethylhexyl 3-mercaptopropionate as the chain transfer agent, show remarkably excellent peel strength (heat seal). On the other hand, the WN is 1786 cm.0 －１ The modified polyolefin resins according to Comparative Examples 1 to 5, which are less than the given values, exhibit inferior peel strength compared to the examples. The modified polyolefin resins according to Comparative Examples 1 and 2, in which the kneaded composition does not contain a chain transfer agent, exhibit inferior peel strength compared to the examples.

Claims

A modified polyolefin resin, It contains a modified polyolefin resin with a modified component, The modified component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives. The Fourier transform infrared absorption spectrum of the modified polyolefin resin has a peak wavenumber of 1786.0 cm⁻¹. －１ 1795.0cm or more －１ A modified polyolefin resin having the following peak: 　 The modified polyolefin resin according to claim 1, further comprising a chain transfer agent. 　 The modified polyolefin resin according to claim 2, wherein the chain transfer agent has an aliphatic hydrocarbon group having 5 or more carbon atoms. 　 The modified polyolefin resin according to claim 2, wherein the chain transfer agent is a thiol-based chain transfer agent. 　 The modified polyolefin resin according to claim 2, wherein the chain transfer agent comprises one or more selected from the group consisting of 1-dodecanethiol and 2-ethylhexyl 3-mercaptopropionate. 　 The modified polyolefin resin according to claim 2, wherein the content of the chain transfer agent is 1 to 5% by weight, based on 100% by weight of the polyolefin resin. 　 A resin composition comprising the modified polyolefin resin described in claim 1. 　 A primer comprising a modified polyolefin resin according to any one of claims 1 to 6 or a resin composition according to claim 7. 　 An adhesive comprising a modified polyolefin resin according to any one of claims 1 to 6 or a resin composition according to claim 7. 　 A paint comprising a modified polyolefin resin according to any one of claims 1 to 6 or a resin composition according to claim 7. 　 An ink comprising a modified polyolefin resin according to any one of claims 1 to 6 or a resin composition according to claim 7. 　 A method for producing a modified polyolefin resin, The modified polyolefin resin includes a modified polyolefin resin due to a modifying component, The modified component comprises one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives. The Fourier transform infrared absorption spectrum of the modified polyolefin resin has a peak wavenumber of 1786.0 cm⁻¹. －１ 1795.0cm or more －１ It has the following peaks: The aforementioned manufacturing method (a) Heating the composition comprising the polyolefin resin, the thiol chain transfer agent, and the modified component. Includes, The above step (a) is performed at a temperature of 150°C to 190°C. The content of the thiol-based chain transfer agent in the composition is 2% by weight or more relative to 100% by weight of the polyolefin resin. A method for producing modified polyolefin resin. 　 A method for producing a modified polyolefin resin according to claim 12, wherein step (a) is performed in an extruder. 　 The method for producing a modified polyolefin resin according to claim 12, wherein the composition in step (a) does not contain a solvent or the solvent content is 0.1% by weight or less, with the weight percentage of the composition being 100% by weight.

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