Article formed by cross-linking silane-modified polyolefin composition

Abstract

To provide an article obtained by cross-linking a silane-modified polyolefin composition, allowing the article to achieve excellent rigidity and impact resistance.SOLUTION: The invention relates to an article formed by cross-linking a silane-modified polyolefin composition, the article having a flexural modulus of 1000 MPa or more and a Charpy impact strength of 3 kJ / m2 or more; or an article formed by cross-linking a silane-modified polyolefin composition, the silane-modified polyolefin composition including a silane-modified product of (a), a silane-modified product of (b), and (c): (a) a propylene-based polymer mainly comprising propylene monomer, (b) an ethylene-based polymer mainly comprising ethylene monomer, and (c) a nucleating agent.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an article comprising a crosslinked silane-modified polyolefin composition. [Background technology]

[0002] Engineering plastics are widely used in a wide range of fields, including automobiles, electrical and electronic equipment, machinery, building materials, food packaging, and safety protection materials. For example, safety protection equipment such as helmets requires high rigidity and impact resistance at low to high temperatures, so engineering plastics such as PC and ABS are used.

[0003] Silane-crosslinkable polyolefins are used in tap water pipes and heating pipes for hot and cold water supply, floor heating, road heating, etc., and are known to exhibit higher durability than non-crosslinked polyolefins (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-81016 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, weight reduction has been studied to reduce the workload of workers who wear protective equipment for long periods of time, and helmets for light work using polyethylene have been put to practical use. According to the study by the present inventors, it has been found that the use of the silane-crosslinkable polyolefin composition described in Patent Document 1 in helmets contributes to weight reduction, but the rigidity and impact resistance are insufficient.

[0006] An object of the present invention is to provide an article made by crosslinking a silane-modified polyolefin composition, which has excellent rigidity and impact resistance. [Means for solving the problem]

[0007] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by an article made from a crosslinked silane-modified polyolefin composition, which article satisfies specific flexural modulus and Charpy impact strength. The present inventors have also found that the above-mentioned problems can be solved by an article obtained by crosslinking a silane-modified polyolefin composition containing a silane-modified propylene-based polymer and an ethylene-based polymer, each of which has been silane-modified, and a crystal nucleating agent.

[0008] That is, the present invention provides the following.

[0009] Aspect 1 of the present invention is An article obtained by crosslinking a silane-modified polyolefin composition, which has a flexural modulus of 1000 MPa or more and a Charpy impact strength of 3 kJ / m, as measured under the following measurement conditions: 2 That's all about the item. (Measurement conditions) Flexural Modulus: Measurements are made in accordance with JIS K7171 (2008) using injection-molded sheet-shaped test pieces with a thickness of 4 mm, length of 80 mm, and width of 10 mm. Charpy impact strength: In accordance with JIS K7111 (2012), an injection-molded, notched sheet-shaped test piece, 4 mm thick, 80 mm long, and 10 mm wide, is immersed in an ethanol solution immersed in dry ice to adjust the liquid temperature to -12°C. After 10 minutes, the test piece is removed from the solution and measurements are carried out immediately within 10 seconds. The measurement capacity is 7.5 J, the impact speed is 3.8 m / s, and the impact strength is calculated using the following formula.

[0010]

number

[0011] A second aspect of the present invention relates to the article of the first aspect, The silane-modified polyolefin composition relates to an article comprising a polyolefin composition obtained by silane-modifying the polyolefin composition comprising the following (a) and (b), and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

[0012] A third aspect of the present invention relates to the article of the second aspect, The mass ratio (a) / (b) of (a) to (b) is 2-19.

[0013] A fourth aspect of the present invention is The present invention relates to an article obtained by crosslinking a silane-modified polyolefin composition, wherein the silane-modified polyolefin composition comprises the following (a) silane-modified, the following (b) silane-modified, and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

[0014] A fifth aspect of the present invention relates to the article of the fourth aspect, The mass ratio (a) / (b) of (a) to (b) is 2-19.

[0015] A sixth aspect of the present invention relates to an article according to any one of the second to fifth aspects, The density of (a) is 0.89 g / cm 3 More than 0.95g / cm 3 or less, and the density of (b) is 0.86 g / cm 3 More than 0.89g / cm 3 relating to an article that is less than

[0016] A seventh aspect of the present invention relates to the article of any one of the second to sixth aspects, The article contains 70% by mass or more and 95% by mass or less of (a) and 5% by mass or more and 30% by mass or less of (b) relative to the total content of (a) and (b) in the silane-modified polyolefin composition.

[0017] Aspect 8 of the present invention relates to the article of any one of aspects 1 to 7, Relating to articles that are any of automobile parts, electrical and electronic equipment parts, machine parts, building materials and food packaging articles.

[0018] A ninth aspect of the present invention relates to the article of any one of the first to seventh aspects, Relating to an article that is a safety device. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide an article made by crosslinking a silane-modified polyolefin composition, which has excellent rigidity and impact resistance. DETAILED DESCRIPTION OF THE INVENTION

[0020] The following describes in detail the embodiments of the present invention, but the following embodiments are merely examples (typical examples) of the present invention, and the present invention is not limited thereto. The present invention can be implemented by modifying it as desired without departing from the gist of the present invention. In this specification, when a numerical value or physical property value is enclosed before and after "~", the values ​​before and after the "~" are included.

[0021] [Goods] The article according to the first embodiment of the present invention is an article obtained by crosslinking a silane-modified polyolefin composition, and has a flexural modulus of 1000 MPa or more and a Charpy impact strength of 3 kJ / m, as measured under the following measurement conditions: 2 That's all. (Measurement conditions) Flexural Modulus: Measurements are made in accordance with JIS K7171 (2008) using injection-molded sheet-shaped test pieces with a thickness of 4 mm, length of 80 mm, and width of 10 mm. Charpy impact strength: In accordance with JIS K7111 (2012), an injection-molded, notched sheet-shaped test piece, 4 mm thick, 80 mm long, and 10 mm wide, is immersed in an ethanol solution immersed in dry ice to adjust the liquid temperature to -12°C. After 10 minutes, the test piece is removed from the solution and measurements are carried out immediately within 10 seconds. The measurement capacity is 7.5 J, the impact speed is 3.8 m / s, and the impact strength is calculated using the following formula.

[0022]

number

[0023] An article according to a second embodiment of the present invention is an article obtained by crosslinking a silane-modified polyolefin composition, and the silane-modified polyolefin composition comprises the following (a) silane-modified, the following (b) silane-modified, and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

[0024] [Silane-modified polyolefin composition] The silane-modified polyolefin composition used in the first embodiment of the present invention preferably contains a silane-modified polyolefin composition containing the following (a) and (b), and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

[0025] The silane-modified polyolefin composition used in the second embodiment of the present invention comprises the following (a) silane-modified, the following (b) silane-modified, and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

[0026] The silane-modified polyolefin composition used in the embodiment of the present invention can be obtained, for example, by mixing (a) to (c) and silane-modifying the mixture. However, industrially, it is preferable to prepare a polyolefin composition before alkoxysilane modification (hereinafter sometimes referred to as the "polyolefin composition according to the embodiment of the present invention") by mixing a propylene polymer before alkoxysilane modification, an ethylene polymer before alkoxysilane modification, an unsaturated silane compound and peroxide for alkoxysilane modification, and other components used as necessary, and then modify the propylene polymer and ethylene polymer contained in this polyolefin composition with alkoxysilane. Furthermore, the crystal nucleating agent (c) may be mixed after the silane modification of (a) and (b).

[0027] The silane-modified polyolefin composition used in the embodiment of the present invention can also be produced by, for example, mixing (a) an alkoxysilane-modified propylene polymer and (b) an alkoxysilane-modified ethylene polymer, each of which has been separately alkoxysilane-modified, and then mixing in a crystal nucleating agent (c). The alkoxysilane modification method in this case can be carried out in the same manner as in the following description, except that the propylene polymer (a) and the ethylene polymer (b) are used separately instead of the mixture of the propylene polymer (a) and the ethylene polymer (b).

[0028] Hereinafter, an embodiment of the present invention will be described in detail in accordance with a method for producing a silane-modified polyolefin composition and then silane-crosslinking the silane-modified polyolefin composition to produce a crosslinked polyolefin composition.

[0029] <(a) Propylene-based polymer mainly composed of propylene monomer> The propylene polymer mainly containing propylene monomers used in the embodiments of the present invention contains propylene units in an amount of more than 80 mass% and not more than 100 mass%, where the total amount of the propylene polymer is 100 mass%. Hereinafter, this propylene polymer mainly containing propylene monomers may be referred to as "propylene polymer (a)".

[0030] The propylene polymer (a) may be a propylene homopolymer or a propylene copolymer obtained by copolymerizing propylene with at least one of an α-olefin other than propylene and a monomer other than an α-olefin, although the term α-olefin as used herein is intended to include ethylene. The propylene copolymer referred to here means a copolymer containing propylene units as a main component. In other words, the propylene copolymer referred to here means a copolymer containing propylene units in the largest amount by mass among the monomers constituting the polymer. The propylene copolymer may be a propylene random copolymer or a propylene block copolymer.

[0031] The α-olefin content in the propylene polymer (a) is usually 20% by mass or less, preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, to achieve high heat resistance and rigidity. A lower α-olefin content is more preferred, and a propylene homopolymer is particularly preferred.

[0032] Examples of the α-olefin other than propylene in the propylene copolymer include, but are not limited to, ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-hexene, and 2,2,4-trimethyl-1-pentene. Among these, α-olefins having 2 to 10 carbon atoms other than propylene, i.e., α-olefins having 2 or 4 to 10 carbon atoms, are preferred, and ethylene, 1-butene, 1-hexene, and 1-octene are more preferred. The propylene copolymer may contain only one type of α-olefin unit other than propylene, or may contain any two or more types.

[0033] Examples of the monomer other than the α-olefin of the propylene copolymer include one or more vinyl bond-containing monomers such as vinyl acetate, vinyl alcohol, (meth)acrylic acid, (meth)acrylic acid alkyl ester, styrene, and styrene derivatives. Here, "(meth)acrylic" refers to either or both of "acrylic" and "methacrylic".

[0034] Specific examples of the propylene polymer (a) include propylene homopolymer, propylene-ethylene copolymer, propylene-C4-20 α-olefin copolymer, and propylene-ethylene-C4-20 α-olefin copolymer.

[0035] The density of the propylene polymer (a) is 0.89 g / cm from the viewpoint of improving rigidity. 3 It is preferable that the concentration is 0.90 g / cm or more. 3 On the other hand, from the viewpoint of improving impact resistance and compatibility with the ethylene polymer, the density of the propylene polymer (a) is usually 0.95 g / cm 3 is less than 0.93 g / cm 3It is preferable that:

[0036] In an embodiment of the present invention, the density of the propylene polymer (a) and the ethylene polymer (b) described below is measured under the following conditions. (Measurement conditions) Measurement is carried out in accordance with JIS K7112 (1999) using a 2 mm thick sheet-shaped test piece obtained by press-molding a silane-modified polyolefin.

[0037] In an embodiment of the present invention, a commercially available product can be used as the propylene polymer (a), and a product having the above-described properties can be appropriately selected from the "Novatec (registered trademark)" series and "Wintech (registered trademark)" series manufactured by Japan Polypropylene Corporation; and the "Prime Polypro (registered trademark)" series manufactured by Prime Polymer Co., Ltd. The propylene polymer (a) may be composed of only one type, or may be composed of two or more types having different monomer unit compositions, physical properties, and the like.

[0038] <(b) Ethylene-based polymers mainly composed of ethylene monomers> The ethylene polymer mainly containing ethylene monomers used in the embodiment of the present invention is an ethylene polymer containing 51% by mass or more and 100% by mass or less of ethylene units, where the total ethylene polymer is taken as 100% by mass. Hereinafter, this ethylene polymer may be referred to as "ethylene polymer (b)".

[0039] The ethylene polymer (b) may be, for example, an ethylene copolymer of ethylene units and α-olefin units other than ethylene, or an ethylene copolymer of ethylene units, α-olefin units other than ethylene, and monomer units other than α-olefin.

[0040] When the ethylene polymer (b) is an ethylene-α-olefin copolymer, the lower limit of the α-olefin unit content is not particularly limited, but is preferably 3% by mass or more, more preferably 6% by mass or more, from the viewpoint of improving impact resistance. The upper limit of the α-olefin unit content is preferably 49% by mass or less, more preferably 46% by mass or less, from the viewpoint of improving rigidity.

[0041] Examples of α-olefins other than ethylene include, but are not limited to, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-hexene, and 2,2,4-trimethyl-1-pentene. Among these, α-olefins having 3 to 10 carbon atoms are preferred, and propylene, 1-butene, 1-hexene, and 1-octene are more preferred. The ethylene polymer (b) may contain only one type of α-olefin unit, or any two or more types.

[0042] Examples of the monomer other than α-olefin include one or more vinyl bond-containing monomers such as vinyl acetate, vinyl alcohol, (meth)acrylic acid, (meth)acrylic acid alkyl esters, styrene, and styrene derivatives. Here, "(meth)acrylic" refers to either or both of "acrylic" and "methacrylic." From the viewpoint of improving rigidity, the content of these monomer units other than α-olefins in the ethylene polymer (b) is preferably 49% by mass or less, more preferably 39% by mass or less. In addition, the lower limit of the content of ethylene units in the ethylene polymer (b), including the case where monomer units other than α-olefins are contained, is preferably 51% by mass or more, more preferably 61% by mass or more, from the viewpoint of improving impact resistance.

[0043] Examples of the ethylene-based polymer (b) include ethylene copolymers such as ethylene-α-olefin copolymers having 4 to 20 carbon atoms and ethylene-butene-α-olefin copolymers having 5 to 20 carbon atoms, and specifically, ethylene-butene copolymers and ethylene-octene copolymers can be used.

[0044] The density of the ethylene polymer (b) is 0.86 g / cm from the viewpoint of improving impact resistance. 3 It is preferable that the concentration is 0.87 g / cm or more. 3 On the other hand, from the viewpoint of improving rigidity, the density of the ethylene polymer (b) is more preferably 0.89 g / cm or more. 3 Preferably, it is less than 0.88 g / cm 3 More preferably, it is:

[0045] The density of the ethylene polymer (b) used in the embodiment of the present invention is measured under the following conditions. (Measurement conditions) The measurement is carried out in accordance with JIS K7112 (1999) using a sheet-like test piece having a thickness of 2 mm obtained by press-molding the silane-modified polyolefin composition.

[0046] In one embodiment, the density of (a) is 0.89 g / cm 3 More than 0.95g / cm 3 or less, and the density of (b) is 0.86 g / cm 3 More than 0.89g / cm 3 It can be less than.

[0047] The ethylene polymer can be produced by any of various known methods, and is not particularly limited. For example, the catalyst used may be a Ziegler-Natta catalyst, a metallocene catalyst, or the like. Among these, an ethylene polymer produced using a metallocene catalyst is preferred from the viewpoints of melting point, impact resistance, molecular weight distribution, and the like.

[0048] In an embodiment of the present invention, the ethylene polymer (b) may be a commercially available product, and the appropriate product may be selected from the "Novatec (registered trademark)" series and "Kernel (registered trademark)" series manufactured by Japan Polyethylene Co., Ltd.; the "Nipolon (registered trademark)" series manufactured by Tosoh Corporation; the "Engage (registered trademark)" series and "Infuse (registered trademark)" series manufactured by The Dow Chemical Company; the "Tafmer (registered trademark)" series and "Evolue (registered trademark)" series manufactured by Mitsui Chemicals, Inc.

[0049] <(c) Nucleating Agent> The nucleating agent used in the embodiment of the present invention promotes crystallization of an article obtained by crosslinking the silane-modified polyolefin composition. The promotion of crystallization improves the rigidity of the resulting article. Hereinafter, this nucleating agent may be referred to as "nucleating agent (c)."

[0050] As the crystal nucleating agent (c), for example, an α-crystal nucleating agent, a β-crystal nucleating agent, or both of these can be used. Among these, the use of an α-crystal nucleating agent is preferred from the viewpoint of improving rigidity.

[0051] Examples of the α-crystal nucleating agent include inorganic crystal nucleating agents and organic crystal nucleating agents. Among these, the organic crystal nucleating agent is preferred from the viewpoint of improving the appearance of the article.

[0052] Examples of organic crystal nucleating agents include calcium stearate, magnesium stearate, sodium benzoate, aluminum benzoate, aluminum dibenzoate, potassium benzoate, lithium benzoate, sodium β-naphthalate, sodium cyclohexyl carboxylate, metal pimelic acid, metal rosinate, and other metal carboxylates.

[0053] Other examples of organic crystal nucleating agents include benzylidene sorbitol such as dibenzylidene sorbitol and its derivatives, phosphate metal salts such as sodium salt of 2-hydroxy-2-oxo-4,6,10,12-tetra-tert-butyl-1,3,2-dibenzo[d,g]perhydrodioxaphosphalocin, and sodium 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate. Further, examples of organic nucleating agents include polymer-type nucleating agents, such as poly-3-methylbutene-1, polyvinylcycloalkane, polyvinyltrialkylsilane, and Kevlar (registered trademark) fiber. Among these, benzylidene sorbitol and its derivatives are more preferred from the viewpoint of improving the appearance of the stretched film.

[0054] Specific examples of commercially available crystal nucleating agents (c) include dibenzylidene sorbitols such as "Gelall MD" (trade name, manufactured by New Japan Chemical Co., Ltd.) and "Gelall LM36G" (trade name, manufactured by New Japan Chemical Co., Ltd.), and Adeka STAB NA-11, NA-27, NA-902, NA-21, and NA-71 (trade name, all five of which are manufactured by ADEKA Corporation).

[0055] Furthermore, a masterbatch containing a nucleating agent (c) can also be used, and examples thereof include a masterbatch containing a mixture of magnesium stearate and silica (manufactured by Dainichiseika Color & Chemicals Co., Ltd., product name "Hi-Cycle Master") and a masterbatch containing the sodium salt of 2-hydroxy-2-oxo-4,6,10,12-tetra-tert-butyl-1,3,2-dibenzo[d,g]perhydrodioxaphosphalocin (manufactured by ADEKA Corporation, product name "ADEKA STAB M-701").

[0056] <Bulking ratio in silane-modified polyolefin composition> The silane-modified polyolefin composition used in the embodiment of the present invention preferably contains 5 to 30 mass % of the ethylene polymer (b) based on the total amount of the propylene polymer (a) and the ethylene polymer (b) used as raw materials. By containing 5% by mass or more of the ethylene polymer (b), the impact resistance of a crosslinked molded article can be improved, and from this viewpoint, a content of 10% by mass or more is more preferable. On the other hand, from the viewpoint of improving the rigidity of the molded and crosslinked article, a content of 30% by mass or less of the ethylene polymer (b) is preferable, and from this viewpoint, a content of 25% by mass or less is more preferable, and a content of 20% by mass or less is even more preferable.

[0057] In other words, the silane-modified polyolefin composition used in the embodiment of the present invention preferably contains 70% by mass or more and 95% by mass or less of (a) and 5% by mass or more and 30% by mass or less of (b) relative to the total content of (a) and (b).

[0058] The mass ratio (a) / (b) of the propylene polymer (a) to the ethylene polymer (b) is preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more. On the other hand, it is preferably 19 or less, more preferably 14 or less, and even more preferably 9 or less. When it is equal to or less than the upper limit, the impact strength is improved, and when it is equal to or more than the lower limit, the rigidity is improved, which are preferable. In one embodiment, the mass ratio (a) / (b) of (a) to (b) may be 2-19.

[0059] The content of the nucleating agent (c) relative to 100 parts by mass of the total of the propylene polymer (a) and the ethylene polymer (b) contained in the silane-modified polyolefin composition is preferably 0.001 parts by mass or more, more preferably 0.005 parts by mass or more, and even more preferably 0.01 parts by mass or more. When the content of the nucleating agent (c) is equal to or greater than the above-mentioned lower limit, crystallization of the polyolefin resin can be sufficiently promoted, improving the rigidity of the resulting article. Furthermore, the content of (c) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 2 parts by mass or less, relative to 100 parts by mass of the total of the propylene polymer (a) and the ethylene polymer (b). A content of the nucleating agent (c) equal to or less than the above-mentioned upper limit is economically advantageous and is preferable because it can suppress bleeding and powdering of the nucleating agent during crosslinking processes, etc.

[0060] The mass ratio (a) / (c) of the propylene polymer (a) to the crystal nucleating agent (c) is preferably 40 or more, more preferably 60 or more, and even more preferably 80 or more. On the other hand, it is preferably 1800 or less, more preferably 1300 or less, and even more preferably 800 or less. A mass ratio of not more than the upper limit is preferred because rigidity is improved, and a mass ratio of not less than the lower limit is preferred from the standpoint of cost.

[0061] [Condensation catalyst] The silane-modified polyolefin composition used in the embodiment of the present invention can contain the above-mentioned silane-modified polyolefin and a silanol condensation catalyst.

[0062] <Silane modification> The silane-modified polyolefin used in the embodiment of the present invention is a mixture of the above-mentioned propylene-based polymer (a) and ethylene-based polymer (b) modified with silane. In one embodiment, the silane-modified polyolefin can be obtained by graft-modifying and / or chemically crosslinking a polyolefin composition containing the above-mentioned propylene-based polymer (a) and ethylene-based polymer (b), together with the below-described unsaturated silane compound, peroxide, and other components blended as necessary.

[0063] The silane modification is preferably graft modification with a silane compound. The silane compound introduced by graft modification is not particularly limited as long as it is a silane compound having an alkoxy group, but the silane-modified site of the silane-modified polyolefin is preferably a polymerized residue of an unsaturated silane compound represented by the following formula (1): R-Si(R')3 (1) In the above formula (1), R is an ethylenically unsaturated hydrocarbon group, and R' are each independently a hydrocarbon group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and at least one of the R' is an alkoxy group having 1 to 10 carbon atoms. R serves as a bonding site during graft introduction into a polyolefin.

[0064] In the above formula (1), R is preferably an ethylenically unsaturated hydrocarbon group having 2 to 10 carbon atoms, and more preferably an ethylenically unsaturated hydrocarbon group having 2 to 6 carbon atoms. Specific examples include alkenyl groups such as vinyl, propenyl, butenyl, and cyclohexenyl.

[0065] In the above formula (1), R' is preferably a hydrocarbon group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, more preferably a hydrocarbon group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms. Furthermore, at least one of the R' is preferably an alkoxy group having 1 to 6 carbon atoms, more preferably an alkoxy group having 1 to 4 carbon atoms.

[0066] In the above formula (1), the hydrocarbon group having 1 to 10 carbon atoms represented by R' may be any of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group, but is preferably an aliphatic hydrocarbon group. Furthermore, the alkoxy group having 1 to 10 carbon atoms represented by R' may be any of linear, branched, and cyclic, but is preferably linear or branched. Specific examples of the hydrocarbon group represented by R' include alkyl groups such as methyl, ethyl, isopropyl, tert-butyl, n-butyl, isobutyl, and cyclohexyl, and aryl groups such as phenyl, but are not limited to these. Specific examples of the alkoxy group represented by R' include methoxy, ethoxy, isopropoxy, and β-methoxyethoxy.

[0067] In the above formula (1), at least one of the three R' is an alkoxy group, but it is preferable that two or more R' are alkoxy groups, and it is more preferable that all three R' are alkoxy groups.

[0068] As the unsaturated silane compound, vinyltrialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, and propenyltrimethoxysilane are particularly preferred. This is because the ethylenically unsaturated hydrocarbon group facilitates silane modification of the starting propylene polymer, and the three alkoxy groups allow the crosslinking reaction described below to occur. That is, the alkoxy groups of the alkoxysilane grafted onto the starting propylene polymer react with water in the presence of a silanol condensation catalyst to hydrolyze and generate silanol groups, and these silanol groups undergo dehydration condensation, resulting in a crosslinking reaction in which the silane-modified polyolefins bond together. The unsaturated silane compounds may be used alone or in combination of two or more.

[0069] The content of the silane compound in the silane-modified polyolefin is not particularly limited, but is preferably 0.1 to 5.0% by mass relative to the total amount of the silane-modified polyolefin from the viewpoints of viscosity during molding, handleability, heat resistance, heat distortion resistance, shape retention, etc. The content of the silane compound in the silane-modified polyolefin is more preferably 0.2% by mass or more, even more preferably 0.3% by mass or more, and is more preferably 4.0% by mass or less, even more preferably 3.0% by mass or less.

[0070] The content of the silane compound is the mass ratio of the unsaturated silane compound introduced by modification to the total amount of polyolefin before modification. The content of the silane compound can be confirmed, for example, by heating and burning a sample to incinerate it, fusing the ash with an alkali, dissolving it in pure water, and quantifying it, followed by ICP atomic emission spectrometry using a high-frequency plasma atomic emission spectrometer.

[0071] The silane-modified polyolefin composition used in the embodiment of the present invention may be grafted with a compound other than the unsaturated silane compound (hereinafter also referred to as "other graft compound"), as long as the effect of the present invention is not impaired. Examples of other graft compounds include, but are not limited to, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, and isocrotonic acid, and acid anhydrides thereof.

[0072] As described above, the silane-modified polyolefin used in the embodiment of the present invention can be produced by grafting a silane compound onto a polyolefin to silane-modify it. The silane-modification method can be carried out according to known techniques and is not particularly limited. For example, solution modification, melt modification, solid-phase modification by irradiation with an electron beam or ionizing radiation, and modification in a supercritical fluid are preferably used. Among these, melt modification, which is excellent in terms of equipment and cost competitiveness, is more preferred, and melt-kneading modification using an extruder, which is excellent in continuous productivity, is even more preferred. Examples of devices used for melt-kneading modification include single-screw extruders, twin-screw extruders, Banbury mixers, and roll mixers. Among these, single-screw extruders and twin-screw extruders, which are excellent in continuous productivity, are preferred.

[0073] Generally, grafting of a silane compound onto a polyolefin can be carried out by a graft polymerization reaction in which the carbon-hydrogen bond of the polyolefin is cleaved to generate a carbon radical, to which an unsaturated functional group is added. The carbon radical can be generated by using the above-mentioned electron beam or ionizing radiation, or by using a high temperature or a radical generator such as an organic or inorganic peroxide. From the viewpoints of cost and operability, it is preferable to use an organic peroxide.

[0074] (radical generator) The radical generator used in producing the silane-modified polyolefin is not particularly limited, but examples thereof include organic peroxides belonging to the hydroperoxide group, dialkyl peroxide group, diacyl peroxide group, peroxy ester group, and ketone peroxide group, and azo compounds.

[0075] Specifically, examples of the hydroperoxide group include cumene hydroperoxide and tertiary butyl hydroperoxide. Examples of the dialkyl peroxide group include dicumyl peroxide, ditertiary butyl peroxide, 2,5-dimethyl-2,5-ditertiary butylperoxyhexane, and 2,5-dimethyl-2,5-ditertiary butylperoxyhexyne-3. Examples of the diacyl peroxide group include lauryl peroxide and benzoyl peroxide. Examples of the peroxy ester group include tertiary peroxyacetate, tertiary butyl peroxybenzoate, and tertiary butyl peroxyisopropyl carbonate. Examples of the ketone peroxide group include cyclohexanone peroxide. Examples of the azo compound include azobisisobutyronitrile and methyl azoisobutyrate. These radical generators may be used alone or in combination of two or more.

[0076] A commonly used melt-kneading modification procedure using an extruder involves compounding and blending a polyolefin, a precursor compound of the silane compound to be grafted (e.g., an unsaturated silane compound), and, if necessary, a radical generator such as an organic peroxide, and feeding the blended mixture into a kneader or extruder, extruding the mixture while heating, melt-kneading, and cooling the molten resin emerging from a die in a water tank or the like to obtain a silane-modified polyolefin.

[0077] The blending ratio of the polyolefin and the precursor compound of the silane compound to be grafted (for example, an unsaturated silane compound) is not particularly limited and may be appropriately set depending on the desired introduction ratio of the silane compound. From the viewpoint of obtaining the desired silane modification amount and reducing the amount of unreacted material remaining, the blending ratio of the precursor compound of the silane compound is preferably 0.3 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the polyolefin.

[0078] The amount of radical generator used, which is blended as needed, can be adjusted appropriately. The amount of radical generator used is not particularly limited, but when an organic peroxide is used, the blending ratio of the organic peroxide is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, per 100 parts by mass of the precursor compound of the silane compound (e.g., an unsaturated silane compound), from the viewpoints of obtaining a desired amount of silane modification and suppressing deterioration of the resulting silane-modified polyolefin.

[0079] The conditions for the melt-extrusion modification are not particularly limited. For example, when a single-screw extruder or a twin-screw extruder is used, the extrusion is preferably carried out at a temperature of about 150 to 300°C.

[0080] (combined agent) The silane-modified polyolefin composition used in the embodiment of the present invention may contain additives commonly used in resin compositions, as long as the effects of the present invention are not impaired. Examples of such additives include heat stabilizers, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, rust inhibitors, viscosity modifiers, and pigments.

[0081] Specific examples of antioxidants include phenol-based, sulfur-based, and phosphorus-based antioxidants, but are not particularly limited to these. The amount of the antioxidant to be added is not particularly limited, but is preferably 0.01 to 2.0 parts by mass, and more preferably 0.1 to 1.0 part by mass, per 100 parts by mass of the silane-modified polyolefin composition.

[0082] Specific examples of ultraviolet absorbers include benzophenone-based absorbers such as 2-hydroxy-4-normal-octyloxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4-carboxybenzophenone, and 2-hydroxy-4-N-octoxybenzophenone; benzotriazole-based absorbers such as 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole and 2-(2-hydroxy-5-methylphenyl)benzotriazole; and salicylate-based ultraviolet absorbers such as phenyl salicylate and p-octylphenyl salicylate, but are not particularly limited to these.

[0083] The amount of the ultraviolet absorber to be added is not particularly limited, but is preferably 0.01 to 1.0 part by mass, and more preferably 0.02 to 0.5 part by mass, per 100 parts by mass of the silane-modified polyolefin composition.

[0084] As the viscosity modifier, rubber compounding oil, specifically paraffinic process oil, is preferred.

[0085] The amount of the viscosity modifier to be added is not particularly limited, but is preferably 0.5 to 5 parts by mass, and more preferably 0.8 to 3 parts by mass, per 100 parts by mass of the silane-modified polyolefin composition.

[0086] [Article obtained by crosslinking a silane-modified polyolefin composition] A silane-modified polyolefin composition is blended with a silanol condensation catalyst, and the resulting composition is molded by various molding methods such as extrusion molding, injection molding, and press molding. The resulting composition is then exposed to a water atmosphere, which promotes a crosslinking reaction between silanol groups and causes an intermolecular crosslinking reaction of the alkoxysilane-modified compounds in the silane-modified polyolefin composition, thereby producing an article in which the silane-modified polyolefin composition is crosslinked. Various conditions can be used for the method of exposing to a water atmosphere, and examples thereof include a method of leaving the material in air containing moisture, a method of blowing air containing water vapor, a method of immersing the material in a water bath, and a method of spraying warm water in a mist.

[0087] More specifically, crosslinking of the silane-modified polyolefin composition proceeds as follows: First, a hydrolyzable alkoxy group derived from a silane compound (e.g., an unsaturated silane compound) grafted onto the silane-modified polyolefin reacts with water in the presence of a silanol condensation catalyst and undergoes hydrolysis to generate a silanol group, and the silanol groups then undergo dehydration condensation with each other, thereby progressing a crosslinking reaction and bonding of the silane-modified polyolefin to each other, thereby crosslinking the silane-modified polyolefin.

[0088] The crosslinking conditions are determined by the conditions for exposure to a water-containing atmosphere and are not particularly limited, but are preferably a temperature range of 20 to 130°C and a time range of 10 minutes to 1 week, more preferably a temperature range of 20 to 130°C and a time range of 1 hour to 160 hours. When using air containing moisture, the relative humidity may be adjusted appropriately within the range of 1 to 100%.

[0089] <Silanol condensation catalyst> Examples of the silanol condensation catalyst used in the embodiment of the present invention include one or more compounds selected from the group consisting of metal organic acid salts, titanates, borates, organic amines, ammonium salts, phosphonium salts, inorganic acids, organic acids, and inorganic acid esters.

[0090] Examples of metal organic acid salts include, but are not limited to, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin diacetate, dibutyltin dioctoate, stannous acetate, stannous octoate, cobalt naphthenate, lead octoate, lead naphthenate, zinc octoate, zinc caprylate, iron 2-ethylhexanoate, iron octoate, and iron stearate. Examples of titanates include, but are not limited to, tetrabutyl titanate, tetranonyl titanate, and bis(acetylacetonitrile)diisopropyl titanate. Examples of organic amines include, but are not limited to, ethylamine, dibutylamine, hexylamine, triethanolamine, tetramethylguanidine, and pyridine. Examples of ammonium salts include, but are not limited to, ammonium carbonate and tetramethylammonium hydroxide. Examples of phosphonium salts include, but are not limited to, tetramethylphosphonium hydroxide. Examples of inorganic and organic acids include, but are not limited to, sulfonic acids such as sulfuric acid, hydrochloric acid, acetic acid, stearic acid, maleic acid, toluenesulfonic acid, and alkylnaphthylsulfonic acid. Examples of inorganic acid esters include, but are not limited to, phosphate esters.

[0091] Among these, preferred are metal organic acid salts, sulfonic acids, and phosphates, and more preferred are metal carboxylates of tin, such as dioctyltin dilaurate, alkylnaphthylsulfonic acids, and ethylhexyl phosphates.The silanol condensation catalysts may be used alone or in appropriate combination of two or more.

[0092] The content of the silanol condensation catalyst in the silane-modified polyolefin composition is not particularly limited. From the viewpoints of suppressing premature crosslinking during molding of a molded article before crosslinking, accelerating the crosslinking reaction during production of an article obtained by crosslinking the silane-modified polyolefin composition, and improving the heat resistance of the resulting three-dimensional network fiber assembly, the content of the silanol condensation catalyst is preferably 0.01 to 0.5 parts by mass, more preferably 0.03 to 0.3 parts by mass, per 100 parts by mass of the silane-modified polyolefin composition.

[0093] The silanol condensation catalyst is preferably used as a silanol condensation catalyst-containing masterbatch, which is a blend of a resin and the silanol condensation catalyst. Examples of resins that can be used in this silanol condensation catalyst-containing masterbatch include homopolypropylene, which is a polymer of propylene; copolymers of propylene with ethylene or α-olefins such as butene, hexene, and octene (excluding propylene); and ethylene copolymers. Among these, homopolypropylene and propylene-ethylene copolymers are preferred from the viewpoints of heat resistance, flexibility, and the like. The propylene-ethylene copolymer is preferably a copolymer of 60 to 98% by mass of propylene and 2 to 40% by mass of ethylene. In the silanol condensation catalyst masterbatch, only one of these polypropylenes may be used alone, or two or more may be used in combination as appropriate.

[0094] When the silanol condensation catalyst is used as a silanol condensation catalyst-containing masterbatch in which a resin and the silanol condensation catalyst are blended, the content of the silanol condensation catalyst in the masterbatch is not particularly limited, but is preferably about 0.1 to 5.0 mass%. Note that a commercially available product can be used as the silanol condensation catalyst-containing masterbatch, for example, "PZ010" manufactured by Mitsubishi Chemical Corporation.

[0095] (Other ingredients) In addition to the silane-modified polyolefin, silanol condensation catalyst, and compounding agents described above, the silane-modified polyolefin composition may contain various additives and resins other than the silane-modified polyolefin as other components within the range that does not impair the effects of the present invention. Here, the resins other than the silane-modified polyolefin include the polyolefin in the silanol condensation catalyst-containing masterbatch and resins other than the polyolefin in the silanol condensation catalyst-containing masterbatch. For example, the silane-modified polyolefin composition may contain the aforementioned compounding agents that can be compounded in the silane-modified polyolefin composition.

[0096] When the silane-modified polyolefin composition contains components other than the above-mentioned silane-modified polyolefin and silanol condensation catalyst, the content of the other components is not particularly limited. From the viewpoint of fully obtaining the effects of containing the silane-modified polyolefin and silanol condensation catalyst, the content of the other components is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, per 100 parts by mass of the silane-modified polyolefin composition.

[0097] Specific examples of other components include thermoplastic solid resins other than polyolefins, solid rubber, liquid resins, softeners, plasticizers, etc. These can also be used as tackifiers to improve adhesion or compatibility, etc. For example, rosin and its derivatives, terpene resins, petroleum resins and their derivatives, alkyd resins, alkylphenol resins, terpene phenol resins, coumarone-indene resins, synthetic terpene resins, alkylene resins, polyisobutylene, polybutadiene, polybutene, copolymers of isobutylene and butadiene, mineral oil, process oil, pine oil, anthracene oil, pine root oil, plasticizers, animal and vegetable oils, polymerized oils, etc. may be contained.

[0098] (Production method of article) In one embodiment, the article obtained by crosslinking the silane-modified polyolefin composition is obtained by a method for producing a crosslinked molded article, the method comprising the steps of obtaining a silane-modified polyolefin containing the above-mentioned propylene-based polymer (a) and ethylene-based polymer (b), obtaining a silane-modified polyolefin composition containing the silane-modified polyolefin and a silanol condensation catalyst, molding the silane-modified polyolefin composition to obtain a molded article, and crosslinking the molded article to obtain a crosslinked molded article.

[0099] [Physical properties of the item] The test pieces used to evaluate the physical properties of the articles of the present invention described below are specifically produced by the method described in the Examples section below.

[0100] The flexural modulus of the article according to the embodiment of the present invention can be measured in accordance with JIS K7171 (2008) using an injection-molded test piece having a thickness of 4 mm, a length of 80 mm and a width of 10 mm.

[0101] The flexural modulus of the article according to the embodiment of the present invention is preferably 1000 MPa or more, more preferably 1050 MPa or more, and even more preferably 1100 MPa or more. There is no particular upper limit to the flexural modulus, and a higher value is preferable. For example, the flexural modulus may be 2500 MPa or less, 2000 MPa or less, or 1800 MPa or less. A flexural modulus equal to or greater than the lower limit is preferable because it provides good rigidity.

[0102] In addition, the Charpy impact strength of the article according to the embodiment of the present invention is 3 kJ / m 2 More preferably, 5 kJ / m or more 2 On the other hand, there is no particular upper limit to the Charpy impact strength, and the higher the value, the better. 2 Below, 300kJ / m 2 Below, 100kJ / m 2 The Charpy impact strength of the steel sheet is preferably equal to or greater than the lower limit, since good impact resistance is obtained. In this specification, the Charpy impact strength is measured as follows.

[0103] Charpy impact strength: In accordance with JIS K7111 (2012), an injection-molded, notched sheet-shaped test piece, 4 mm thick, 80 mm long, and 10 mm wide, is immersed in an ethanol solution immersed in dry ice to adjust the liquid temperature to -12°C. After 10 minutes, the test piece is removed from the solution and measurements are carried out immediately within 10 seconds. The measurement capacity is 7.5 J, the impact speed is 3.8 m / s, and the impact strength is calculated using the following formula.

[0104]

number

[0105] [Application] The uses of the article according to the embodiment of the present invention are not particularly limited. For example, it can be suitably used as furniture, bedding such as bed mats and pillows; cushioning materials for vehicle seats such as those for vehicles and ships; automobile parts, electrical and electronic equipment parts, machine parts and other components; building materials; and food packaging articles. The article according to the embodiment of the present invention is particularly preferably any one of automobile parts, electrical and electronic equipment parts, machine parts, building materials, and food packaging articles. Furthermore, since the article is lightweight and has excellent rigidity and impact resistance, it can be particularly suitably used as a safety protector. That is, the article according to the embodiment of the present invention is also preferably a safety protector. [Example]

[0106] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples as long as it does not depart from the gist of the invention. Furthermore, the values ​​of various production conditions and evaluation results in the following examples are meant as preferred upper or lower limit values ​​in the embodiments of the present invention, and preferred ranges may be defined by combining the above-mentioned upper or lower limit values ​​with the values ​​in the following examples or values ​​between the examples.

[0107] [Raw materials] The raw materials used in the examples and comparative examples are shown below. <Propylene-based polymer (a)> PP-1: Novatec (registered trademark) EA9 (Japan Polypropylene Corporation, MFR: 0.5 g / 10 min, density: 0.90 g / cm 3 ) PP-2: VX200N (SunAllomer Co., Ltd., MFR: 0.5 g / 10 min, density: 0.90 g / cm 3 ) PP-3: ZELAS (registered trademark) 7025 (manufactured by Mitsubishi Chemical Corporation, MFR: 2.5 g / 10 min, density: 0.90 g / cm 3 ) <Ethylene polymer (b)> PE-1: Engage (registered trademark) 8150 (manufactured by The Dow Chemical Company, MFR: 0.5 g / 10 min, density: 0.87 g / cm 3 ) PE-2: Infuse (registered trademark) 9000 (manufactured by The Dow Chemical Company, MFR: 0.5 g / 10 min, density: 0.88 g / cm 3 ) PE-3: Infuse (registered trademark) 9010 (manufactured by The Dow Chemical Company, MFR: 0.5 g / 10 min, density: 0.88 g / cm 3 ) <Unsaturated silane compounds> S-1: KBM-1003 (Shin-Etsu Chemical Co., Ltd., vinyltrimethoxysilane) <Peroxide> POX-1: Perbutyl O (NOF Corporation, tert-butyl peroxyoctoate) POX-2: Perbutyl D (NOF Corporation, di-tert-butyl peroxide) <Nucleating Agent (c)> NA-1: ADK STAB (registered trademark) NA-27 (manufactured by ADEKA Corporation, organic crystal nucleating agent) NA-2: ADK STAB (registered trademark) NA-11 (manufactured by ADEKA Corporation, organic crystal nucleating agent) <Crosslinking catalyst masterbatch> MB-1: Linkron (registered trademark) catalyst masterbatch PZ010 (manufactured by Mitsubishi Chemical Corporation, MFR: 16 g / 10 min, density: 0.92 g / cm 3 )

[0108] [Measurement and evaluation method] (Measurement of polyolefin composition) <Melt flow rate (MFR)> According to JIS K7210 (1999), the propylene polymer and the crosslinking catalyst masterbatch were measured at 230°C and 21.2N, and the ethylene polymer was measured at 190°C and 21.2N. <density> Measurement was carried out in accordance with JIS K7112 (1999) using a sheet-like test piece having a thickness of 2 mm obtained by press-molding the polyolefin composition.

[0109] (Measurement of items) <Gel fraction> A sheet (2 mm thick) of crosslinked silane-modified polyolefin composition was subjected to Soxhlet extraction for 10 hours in boiling xylene at 144°C, and the undissolved resin was dried and then measured for mass, which was calculated as a percentage (%) of the sample mass before Soxhlet extraction. <density> Measurement was carried out in accordance with JIS K7112 (1999) using a sheet-like test piece having a thickness of 2 mm obtained by press-molding the polyolefin composition. <Flexural modulus> Measurements were made in accordance with JIS K7171 (2008) using injection-molded sheet-shaped test pieces with a thickness of 4 mm, a length of 80 mm, and a width of 10 mm. <Charpy impact strength> In accordance with JIS K7111 (2012), an injection-molded, notched sheet specimen measuring 4 mm thick, 80 mm long, and 10 mm wide was immersed in an ethanol solution containing dry ice, the temperature of which was adjusted to -12°C. After 10 minutes, the specimen was removed from the solution and measurements were carried out immediately within 10 seconds. The measurement capacity was 7.5 J, and the impact speed was 3.8 m / s. The impact strength was calculated using the following formula:

[0110]

number

[0111] <Production of silane-modified polyolefins and articles> [Example 1] As shown in Table 1, 80 parts by mass of PP-1, 10 parts by mass of PP-2, 10 parts by mass of PE-2, 2 parts by mass of S-1, 0.8 parts by mass of POX-1, and 0.2 parts by mass of NA-1 were mixed in a blender. The mixture was then fed into a single-screw extruder (IKG Corporation, PMS50) set at 200°C. The strands emerging from the nozzle were cooled and solidified in a water bath and then cut into pellets to obtain silane-modified polyolefin composition A (hereinafter referred to as "composition A"). The MFR of the resulting composition A was measured according to the measurement and evaluation method described above. The results are shown in Table 1. Five parts by mass of MB-1, a silanol condensation catalyst masterbatch, were then added to 100 parts by mass of composition A, and the mixture was dry-blended. The mixture was then fed into an injection molding machine and molded into 4 mm or 2 mm sheets at 220°C. This sheet-like molded article was left in a thermo-hygrostat at 85°C and 85% RH for 16 hours to obtain a sheet-like article A (hereinafter referred to as "article A") in which the silane-modified polyolefin composition was crosslinked. Using article A, the gel fraction, density, flexural modulus, and Charpy impact strength were measured according to the above-mentioned measurement and evaluation methods. The results are shown in Table 1.

[0112] [Examples 2 to 7, Comparative Examples 1 to 4] Silane-modified polyolefin compositions B to I and K, and polyolefin composition J (hereinafter referred to as "compositions B to I, K, J," respectively) were obtained in the same manner as in Example 1, except that the raw material blending compositions were as shown in Table 1. The MFR of the obtained compositions B to K was measured in the same manner as in Example 1. The results are shown in Table 1. Furthermore, compositions B to K were used to obtain sheet-like articles B to K (hereinafter referred to as "articles B to K," respectively) in the same manner as in Example 1. Using articles B to K, the gel fraction, density, flexural modulus, and Charpy impact strength were measured in the same manner as in Example 1. The results are shown in Table 1.

[0113] [Table 1]

[0114] <Evaluation results> As shown in Table 1, all of the articles A to G produced in Examples 1 to 7 had a flexural modulus of 1000 MPa or more and a Charpy impact strength of 5 kJ / m at low temperature (-12°C). 2 These results demonstrate a good balance between rigidity and impact resistance. Furthermore, since articles A to G had a gel fraction greater than 0, indicating crosslinking, they are expected to have improved durability, heat resistance, and chemical resistance compared to uncrosslinked articles, making them suitable as replacements for engineering plastic articles. Furthermore, because articles A to G had low density, they were able to maintain their light weight. On the other hand, it was found that the articles H to K produced in Comparative Examples 1 to 4 respectively had a poor balance between rigidity and impact resistance and were not suitable as replacements for articles made of engineering plastics. [Industrial Applicability]

[0115] The articles according to the embodiments of the present invention are lightweight and have improved rigidity and impact resistance, and therefore can be suitably used in any of automobile parts, electrical and electronic equipment parts, machine parts, building materials, and food packaging articles, as well as safety protectors.

Claims

1. An article obtained by crosslinking a silane-modified polyolefin composition, which has a flexural modulus of 1000 MPa or more and a Charpy impact strength of 3 kJ / m, as measured under the following measurement conditions: ２ That's it, goods. (Measurement conditions) Flexural modulus: Measurement is carried out in accordance with JIS K7171 (2008) using an injection-molded sheet-like test piece having a thickness of 4 mm, a length of 80 mm, and a width of 10 mm. Charpy impact strength: In accordance with JIS K7111 (2012), an injection-molded, notched sheet-shaped test piece measuring 4 mm thick, 80 mm long, and 10 mm wide was immersed in an ethanol solution containing dry ice, the temperature of which was adjusted to -12°C. After 10 minutes, the test piece was removed from the solution and measurements were carried out immediately within 10 seconds. The measurement capacity was 7.5 J, the impact speed was 3.8 m / s, and the impact strength was calculated using the following formula: [Equation 1]

2. The article according to claim 1, wherein the silane-modified polyolefin composition comprises a silane-modified polyolefin composition comprising the following (a) and (b): and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

3. The article according to claim 2, wherein the mass ratio (a) / (b) of (a) to (b) is 2 to 19.

4. An article obtained by crosslinking a silane-modified polyolefin composition, the silane-modified polyolefin composition comprising the following (a) silane-modified, the following (b) silane-modified, and the following (c): (a) Propylene-based polymers mainly composed of propylene monomers (b) Ethylene-based polymers mainly composed of ethylene monomers (c) Nucleating Agent

5. 5. The article according to claim 4, wherein the mass ratio (a) / (b) of (a) to (b) is 2 to 19.

6. The density of (a) is 0.89 g / cm ３ 0.95g / cm or more ３ or less, and the density of (b) is 0.86 g / cm ３ 0.89g / cm or more ３ 5. The article of claim 2 or 4, wherein the thickness is less than 1 / 2 mm.

7. The article according to claim 2 or 4, wherein the silane-modified polyolefin composition contains 70% by mass or more and 95% by mass or less of (a) and 5% by mass or more and 30% by mass or less of (b) relative to the total content of (a) and (b).

8. The article according to claim 1 or 4, which is any one of an automobile part, an electric / electronic device part, a machine part, a building material, and a food packaging article.

9. 10. The article of claim 1 or 4, which is a safety device.

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