WO2023095891A1

WO2023095891A1 - Resin composition and molded article containing same

Info

Publication number: WO2023095891A1
Application number: PCT/JP2022/043618
Authority: WO
Inventors: 雅也隣; 大介堂山
Original assignee: Ｕｂｅ株式会社
Priority date: 2021-11-26
Filing date: 2022-11-25
Publication date: 2023-06-01

Abstract

The present invention pertains to a resin composition that is obtained by blending an elastomer (A) that has a soft segment including a polyether, and a modified polyethylene (B). The modified polyethylene (B) is obtained by modifying a polyethylene having a density of 0.910-0.925 g/cm³ ³ and/or a weight average molecular weight (Mw) of 1,000,000 or more. The resin composition contains 50.00-90.00 mass% of the elastomer (A) when the total of the elastomer (A) and the modified polyethylene (B) is defined as 100 mass%. According to the present invention, it is possible to provide a resin composition that has superior mechanical properties and tensile permanent strain.

Description

Resin composition and molded article containing the same

The present invention relates to resin compositions, particularly polyamide resin compositions, and molded articles containing the same.

Elastomers having a polyether structure as a soft segment have been proposed as resin compositions to replace rubber used in packings, vibration-isolating rubbers, rubber hoses, etc. Among them, resin compositions containing polyester elastomers and polyamide elastomers have been proposed. there is No. 5,200,000 describes a composition comprising a polyamide, a polyamide elastomer that is a copolymer comprising polyamide blocks and polyether blocks, and a single polyolefin functionalized with maleic anhydride units or epoxy units, and exhibits low flexural modulus. It is disclosed to show the rate. In Patent Document 2, a composition containing predetermined amounts of a semicrystalline polyamide, an amorphous polyamide, a compatibilizer for the polyamide, and a polyamide elastomer that is a flexible polyamide has a high breaking elongation and a low bending It is disclosed to exhibit elastic modulus and high impact resistance.

JP-A-2002-275371 Japanese Patent Publication No. 2016-535164

However, in compositions containing polyamide elastomers (elastomers having polyether structures as soft segments) as disclosed in Patent Documents 1 and 2, there is room for further improvement in terms of tensile set and mechanical properties. Something was discovered. That is, according to the findings of the inventors, in a composition containing a polyamide elastomer (elastomer having a polyether structure as a soft segment), among the indicators of mechanical properties, tensile yield stress, tensile modulus, bending strength and When excellent in all bending elastic moduli, there were cases where the impact resistance was inferior. In addition, in a composition containing a polyamide elastomer (elastomer having a polyether structure as a soft segment), when all of the tensile yield stress, tensile modulus, flexural strength and flexural modulus are excellent, the tensile permanent set may be inferior. there were. Moreover, in a composition containing a polyamide elastomer (an elastomer having a polyether structure as a soft segment), even when the composition is excellent in impact resistance, the tensile set may be poor. Thus, it was found that there is room for further improvement in achieving both excellent mechanical properties and excellent tensile set.

Accordingly, an object of the present invention is to provide a resin composition that is excellent in tensile set and mechanical properties.

The present invention relates to the following. The present invention particularly relates to a resin composition, a molded article, and a production method, wherein the elastomer (A) is an elastomer having a polyether structure as a soft segment in the following aspects [1] to [10].
[1] A resin composition obtained by blending an elastomer (A) having a polyether structure as a soft segment and a modified polyethylene (B), wherein the modified polyethylene (B) has a density of 0.910 g/cm ³ or more and 0.925 g/cm ³ or less and/or polyethylene having a weight average molecular weight (Mw) of 1 million or more, unsaturated carboxylic acid or its derivative, hydroxyl group-containing ethylenically unsaturated compound, amino group-containing ethylenic It is modified with an unsaturated compound or a vinyl group-containing organosilicon compound, and when the total of the elastomer (A) and the modified polyethylene (B) is 100% by mass, the elastomer (A) is 50.00% A resin composition containing ~90.00% by mass.
[2] The resin composition of [1], wherein the elastomer (A) contains at least one selected from the group consisting of polyether polyamide elastomers and polyether polyester elastomers.
[3] The resin composition of [1] or [2], wherein the elastomer (A) has a hard segment to soft segment mass ratio of 95/5 to 30/70.
[4] The resin composition according to any one of [1] to [3], containing 5.00 to 50.00% by mass of the modified polyethylene (B) in the resin composition.
[5] The resin composition according to any one of [1] to [4], further comprising 0.01 to 5.00% by mass of a cross-linking agent.
[6] The resin composition of any one of [1] to [5], wherein the resin composition further contains 0% by mass or more and less than 10.00% by mass of a polyamide resin (excluding the elastomer (A)). thing.
[7] An ISO TYPE A 2 mm thick test piece prepared according to ISO 294-1 is subjected to 20% strain and 30 minutes with a tensile tester based on JIS K 6273 in an environment of 23 ° C. and 50% relative humidity. The resin composition of [1] to [6], which has a tensile set of 29.5% or less when subjected to a tensile set test.
[8] The resin composition of any one of [1] to [7], which has a bending elastic modulus of 100 MPa or more, measured according to ISO 527, using an ISO TYPE A-shaped 4 mm thick test piece prepared according to ISO 294-1. thing.
[9] A molded article comprising the resin composition according to any one of [1] to [8].
[10] A method for producing a molded product, which comprises injection molding the resin composition according to any one of [1] to [9] at a cylinder temperature of 200 to 250°C and a mold temperature of 30 to 50°C.

According to the present invention, it is possible to provide a resin composition that is excellent in tensile set and mechanical properties.

As used herein, the content of each component in the composition refers to the total amount of the multiple substances present in the composition when there are multiple substances corresponding to each component in the composition, unless otherwise specified. means.
In this specification, "-" indicating a numerical range means that the numerical values described before and after it are included as lower and upper limits. For example, "50.00 to 90.00% by mass" means "50.00% by mass or more and 90.00% by mass or less".
In addition, when the term “mixed” is used in this specification, a product obtained by mixing includes a product simply containing each component and a product in which at least a part of them has reacted.

[Resin composition]
The resin composition of the present invention comprises an elastomer (A) having a soft segment containing a polyether and a modified polyethylene (B), wherein the modified polyethylene (B) comprises a modified low-density polyethylene and a modified ultra-high molecular weight It is at least one selected from the group consisting of polyethylene, and contains 50.00 to 90.00% by mass of the elastomer (A) in the resin composition.

[Elastomer (A)]
The elastomer (A) has, in its structure, a soft segment exhibiting rubber elasticity and a hard segment acting as a pseudo cross-linking point, and the soft segment includes a polyether structure.

As hard segments contained in the elastomer (A), polyamide units, polyester units, polypropylene units, urethane bonds, etc. can be used. The elastomer (A) preferably has polyamide units or polyester units as hard segments. That is, the elastomer (A) preferably contains at least one selected from the group consisting of polyamide elastomers and polyester elastomers. Elastomer (A) is particularly preferably a polyamide elastomer.

[Polyamide elastomer]
Polyamide elastomers include polyamide elastomers having polyamide units as hard segments and polyether units as soft segments. Polyamide elastomers are selected from the group consisting of polyether polyester amide elastomers in which hard segments and soft segments are linked by ester bonds, and polyether amide elastomers in which hard segments and soft segments are linked by amide bonds, from the viewpoint of the balance of mechanical properties. At least one selected is preferred.

The hard segment can be derived from a polyamide having carboxyl groups at both end groups, and polyamide-forming units and at least one dicarboxylic acid selected from the group consisting of aliphatic dicarboxylic acids, alicyclic dicarboxylic acids and aromatic dicarboxylic acids. A segment containing an acid.

The polyamide-forming units in the hard segment are units formed from lactams, aminocarboxylic acids, and/or diamines and dicarboxylic acids (nylon salts). Examples of the aforementioned components include units obtained by reacting one or more selected from the group consisting of lactams, aminocarboxylic acids, diamines and dicarboxylic acids (nylon salts).

Lactams include aliphatic lactams having 4 to 20 carbon atoms such as 2-pyrrolidinone, ε-caprolactam, ω-heptalactam, ω-undecalactam and ω-dodecanelactam.
Aminocarboxylic acids include 6-aminohexanoic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminononanoic acid, 10-aminodecanoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and the like. 5 to 20 aliphatic ω-aminocarboxylic acids and the like.
Diamines include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, ,4-trimethylhexane-1,6-diamine, 2,4,4-trimethylhexane-1,6-diamine, 3-methylpentane-1,5-diamine and other aliphatic diamines having 2 to 20 carbon atoms, etc. and diamine compounds.
Among these, it is selected from the group consisting of ω-undecalactam, ω-dodecanelactam, 11-aminoundecanoic acid and 12-aminododecanoic acid from the viewpoint of dimensional stability due to low water absorption, chemical resistance, and mechanical properties. At least one is preferred.

Hard segment dicarboxylic acids can be used as molecular weight modifiers. Dicarboxylic acids include linear aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and dodecanedioic acid; triglycerides; Aliphatic dicarboxylic acids such as dimerized aliphatic dicarboxylic acids having 14 to 48 carbon atoms (dimer acids) and hydrogenated products thereof (hydrogenated dimer acids) obtained by dimerizing unsaturated fatty acids obtained by fractional distillation of; terephthalic acid , isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, dibenzoic acid C8-22 aromatics such as acids, 4,4'-oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid and 4,4'-biphenyldicarboxylic acid group dicarboxylic acids; alicyclic dicarboxylic acids having 5 to 22 carbon atoms such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; and dicarboxylic acid compounds. A polyamide having carboxyl groups at both ends can be obtained by ring-opening polymerization or polycondensation of the above polyamide-forming units in the presence of a dicarboxylic acid in a conventional manner.
Among these, adipic acid, oxalic acid, dodecanedioic acid, sebacic acid and dimer acid are preferred. As the dimer acid and the hydrogenated dimer acid, trade names such as "PRIPOL 1004", "PRIPOL 1006", "PRIPOL 1009" and "PRIPOL 1013" manufactured by Croda can be used.

The number average molecular weight of the hard segment is preferably 300 to 15,000, more preferably 300 to 6,000 from the viewpoint of flexibility and moldability.

Soft segments include polyether. The soft segment is preferably polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, ABA-type triblock polyether represented by the following formula (1), or the like. These can be used alone or in combination of two or more. Also, polyether diamine or the like obtained by reacting the end of polyether with ammonia or the like can be used. The soft segment preferably has a number average molecular weight of 200 to 6,000, more preferably 650 to 2,000.

(Wherein, x is 1 to 20, y is 4 to 50, and z is 1 to 20.)

Each of x and z is independently an integer of preferably 1 to 18, more preferably an integer of 1 to 16, more preferably an integer of 1 to 14, and particularly preferably an integer of 1 to 12. Also, y is preferably an integer of 5 to 45, more preferably an integer of 6 to 40, even more preferably an integer of 7 to 35, and particularly preferably an integer of 8 to 30.

[Polyester elastomer]
The polyester elastomer having polyester units as hard segments preferably contains an aromatic polyester as a constituent unit of the hard segments. Examples of aromatic polyesters introduced into the hard segment of elastomer (A) include polymethylene terephthalate, polyethylene terephthalate, polybutylene terephthalate and polybutylene naphthalate.

The aromatic polyester used to form polyester units as hard segments can be formed, for example, from an aromatic dicarboxylic acid and an aliphatic diol. Aromatic dicarboxylic acids may be derivatives capable of forming esters by reaction with alcohols, such as acid anhydrides and acid halides.

Dicarboxylic acids from which polyester units as hard segments are formed include isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, derivatives thereof, and the like.

Diols used to form polyester units as hard segments include aliphatic diols such as ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol; Alicyclic diols such as methanol and tricyclodecanedimethylol; xylylene glycol, bis(p-hydroxy)diphenyl, bis(p-hydroxyphenyl)propane, 2,2-bis[4-(2-hydroxyethoxy)phenyl ] propane, bis[4-(2-hydroxy)phenyl]sulfone, 1,1-bis[4-(2-hydroxyethoxy)phenyl]cyclohexane, 4,4′-dihydroxy-p-terphenyl, 4,4′ -dihydroxy-p-quarterphenyl and other aromatic diols. These diols preferably have a molecular weight of 300 or less because they are advantageous in forming hard segments.

As a combination of the hard segment and the soft segment, each combination of the hard segment and the soft segment mentioned above can be mentioned. Among these, a combination of ring-opening polycondensate of lauryllactam/polyethylene glycol, a combination of ring-opening polycondensate of lauryllactam/polypropylene glycol, a combination of ring-opening polycondensate of lauryllactam/polytetramethylene ether glycol, and lauryllactam A ring-opening polycondensate/ABA-type triblock polyether combination, a combination of polybutylene terephthalate/polyethylene glycol, a combination of polybutylene terephthalate/polypropylene glycol, and a combination of polybutylene terephthalate/polybutylene glycol are preferred, and a combination of lauryl lactam is preferred. A ring polycondensate/ABA-type triblock polyether combination is particularly preferred.

The ratio (mass ratio) between the hard segment and the soft segment is preferably hard segment/soft segment=95/5 to 30/70. Within this range, it is easy to ensure sufficient flexibility. The hard segment/soft segment (mass ratio) is more preferably 90/10 to 35/65, particularly preferably 80/20 to 40/60. The hard segment/soft segment (mass ratio) may be 95/5 to 70/30, or 70/30 to 30/70. Here, when a plurality of elastomers (A) are present, the hard segment/soft segment (mass ratio) is an average value according to the mass of each component.

Commercially available elastomers such as those described above include Daiamide (registered trademark) manufactured by Daicel-Evonik, Pebax (registered trademark) manufactured by ARKEMA, Grilamid (registered trademark) manufactured by Em Chemie Japan, Hyper Alloy Actimer (registered trademark), manufactured by DSM: Novamit (registered trademark), manufactured by UBE Ube Industries: UBESTA (registered trademark) XPA series, manufactured by Toray DuPont: Hytrel (registered trademark), and the like.

Among them, "UBESTA (registered trademark) XPA 9040X1, 9040F1, 9048X1, 9048F1, 9055X1, 9055F1, 9063X1, 9063F1, 9068X1, 9068F1" (manufactured by UBE), "Pebax (Registered Trademarks 2533, 3533, 4033, 5533, 6333, 7033 and 7233 (manufactured by ARKEMA) are preferred.

Multiple types of elastomers (A) may be used in combination.

[Modified polyethylene (B)]
Modified polyethylene (B) is at least one selected from the group consisting of modified low-density polyethylene and modified ultra-high molecular weight polyethylene. Modified low density polyethylene is low density polyethylene that has been modified with a compound containing modifying groups. Modified ultra-high molecular weight polyethylene is ultra-high molecular weight polyethylene modified with a compound containing a modifying group. The molecular weight of the modified low-density polyethylene is not particularly limited, and the density of the modified ultra-high molecular weight polyethylene is not particularly limited.

The polyethylene (unmodified polyethylene) in the modified polyethylene (B) is a low-density polyethylene having a density of 0.910 g/cm ³ or more and 0.925 g/cm ³ or less, and an ultra-high-density polyethylene having a weight average molecular weight (Mw) of 1 million or more. Molecular weight polyethylene (UHMWPE). Here, ultra high molecular weight polyethylene (UHMWPE) is linear or branched polyethylene, and the weight average molecular weight (Mw) of ultra high molecular weight polyethylene (UHMWPE) is measured by gel permeation chromatography (GPC). can be done. Specific measurement conditions include the following method. About 8 mg of a sample of ultra-high molecular weight polyethylene (UHMWPE) is dissolved in 8 ml of 1,2,4-trichlorobenzene at 160° C. for 90 minutes to obtain a sample solution. 200 μl of the sample solution obtained are then injected into a high temperature GPC equipped with an infrared detector at a column zone of 145° C. and a detector zone of 160° C. at a flow rate of 0.5 ml/min. Here, the low density polyethylene may be linear low density polyethylene (LLDPE) or branched low density polyethylene (LDPE). The polyethylene (unmodified polyethylene) in the modified polyethylene (B) is at least one selected from the group consisting of branched low-density polyethylene (LDPE) and ultra-high molecular weight polyethylene (UHMWPE) from the viewpoint of reducing tensile set. is preferred. The unmodified polyethylene may be a homopolymer of ethylene, but if it is mainly composed of ethylene, it may contain a small amount of other monomers, such as 5 mol% or less of α-olefin monomers, or 1 mol% or less of non-modified polyethylene. It may be a copolymer containing an olefin monomer.

Examples of modifying groups in compounds containing modifying groups include acid modifying groups such as carboxyl groups and sulfonic acid groups; and carboxyl metal salts, acid anhydride groups, amino groups, hydroxyl groups, silanol groups, alkoxy groups, hydroxyl groups, and epoxy groups. , an isocyanate group, a mercapto group, an oxazoline group, and other modifying groups other than acid modifying groups. The compound containing a modifying group is preferably an unsaturated carboxylic acid or derivative thereof, a hydroxyl group-containing ethylenically unsaturated compound, an amino group-containing ethylenically unsaturated compound, a vinyl group-containing organosilicon compound, or the like. Examples of unsaturated carboxylic acids or derivatives thereof include unsaturated compounds having one or more carboxyl groups, esters of compounds having carboxyl groups and alkyl alcohols, and unsaturated compounds having one or more anhydrous carboxyl groups. Examples of unsaturated groups include vinyl groups, vinylene groups, and unsaturated cyclic hydrocarbon groups. The compound containing a modifying group is preferably a compound containing an acid modifying group, particularly preferably an unsaturated carboxylic acid or a derivative thereof, from the viewpoint of reactivity with functional groups present at the ends of the elastomer.

Specific examples of unsaturated carboxylic acids include acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, mesaconic acid, citraconic acid, crotonic acid, isocrotonic acid, endocis-bicyclo[2,2,1]hept- Unsaturated dicarboxylic acids such as 5-ene-2,3-dicarboxylic acid are included. Examples of unsaturated carboxylic acid derivatives include acid halides, amides, imides, anhydrides and esters of the unsaturated carboxylic acids. Malenyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, Dimethyl maleate, glycidyl maleate and the like are preferred. From the viewpoint of reactivity, the unsaturated carboxylic acid or derivative thereof is more preferably at least one selected from the group consisting of maleic anhydride and acrylic acid, and particularly preferably maleic anhydride.

Modification of unmodified polyethylene with a compound containing a modifying group can be performed during or after synthesis of unmodified polyethylene. Here, the amount of the compound containing the modifying group to be used can be appropriately set according to the desired modification amount of the polyethylene.

Commercially available modified polyethylene (B) includes F3000 (trade name) manufactured by Ube Maruzen Polyethylene Co., Ltd., Admer (registered trademark) NF528T manufactured by Mitsui Chemicals, Inc., Lubmer (registered trademark) LY1040 manufactured by Mitsui Chemicals, Inc., and Admer (registered trademark) NB550, Modic (registered trademark) M545 manufactured by Mitsubishi Chemical Corporation, Adtex (registered trademark) L6100M manufactured by Japan Polyethylene Co., Ltd., Admer (registered trademark) NB508 manufactured by Mitsui Chemicals, Admer manufactured by Mitsui Chemicals, Inc. (registered trademark) HE810, Admer (registered trademark) NF567 manufactured by Mitsui Chemicals, Inc., and the like.

When the modified polyethylene (B) is a modified low density polyethylene, it is preferably a branched modified low density polyethylene (LDPE).

The modified polyethylene (B) may be a single component or a combination of two or more components. Here, in addition to the modified polyethylene (B), the above-mentioned unmodified polyethylene can also be added. When unmodified polyethylene is used, its amount is preferably 20.00 mass % or less of the total composition. The amount of unmodified polyethylene is preferably 50.00 mass % or less based on the total amount of modified polyethylene (B).

[Additive (C)]
The resin composition may contain an additive (C) as long as the effects of the present invention are not impaired. Additives (C) include, for example, weathering agents, cross-linking agents, further polyamide resins (excluding elastomer (A)), antioxidants, heat stabilizers, heat-resistant agents, thickeners, molecular weight (viscosity) Regulators, UV absorbers, light stabilizers, antistatic agents, lubricants, antiblocking agents, antifogging agents, crystal nucleating agents, release agents, plasticizers, foaming agents, colorants (pigments, dyes, etc.), etc. be done. In the production of the elastomer (A) and the modified polyethylene (B), a component corresponding to the additive (C) (for example, an antioxidant) may be used. In this case, the component corresponding to the additive (C) shall be contained as the (C) component in the resin composition.

Examples of cross-linking agents include cross-linking agents having at least one group selected from the group consisting of carbodiimide groups, carboxyl groups, acid anhydride groups, isocyanate groups, epoxy groups, alkoxysilane groups and allyl groups. The cross-linking agent is preferably a cross-linking agent having a carbodiimide group, and particularly preferably a cross-linking agent having a carbodiimide group having a cyclic structure, from the viewpoint of the need to efficiently form a cross-linked structure. Further, the cross-linking agent having a carbodiimide group having a cyclic structure does not liberate an isocyanate group when reacting with at least one selected from the group consisting of the elastomer (A) and the modified polyethylene (B) from the viewpoint of working environment conservation. is particularly preferred from

Examples of antioxidants include organic antioxidants and inorganic antioxidants.
Examples of organic antioxidants include phenol antioxidants, phosphorus antioxidants, sulfur antioxidants, and the like. From the viewpoint of improving the antioxidant performance of the molded article, the organic antioxidant is preferably at least one selected from the group consisting of phenol antioxidants, phosphorus antioxidants and sulfur antioxidants. , a phenolic antioxidant and a phosphorus antioxidant.
Specific examples of phenolic antioxidants include N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide (Irganox (registered trademark) 1098; BASF Japan Ltd. manufactured by), pentaerythrityl-tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate] (Irganox (registered trademark) 1010; manufactured by BASF Japan Ltd.), ethylene bis (oxyethylene ) bis [3-(5-tert-butyl-4-hydroxy-m-tolyl) propionate] (Irganox (registered trademark) 245; manufactured by BASF Japan Ltd.), 3,9-bis [2-[3-(3 -tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (Sumilyzer® GA -80; manufactured by Sumitomo Chemical Co., Ltd.), and at least one selected from the group consisting of these is preferable.The phenolic antioxidants may be used singly or in combination of two or more.
Specific examples of phosphorus antioxidants include tris(2,4-di-t-butylphenyl) phosphite (Irgafos (registered trademark) 168; manufactured by BASF Japan Ltd.), bis(2,6-di-t -Butyl-4-methylphenyl)pentaerythritol diphosphite (ADEKA STAB (registered trademark) PEP-36; manufactured by ADEKA Corporation), tetrakis(2,4-di-tert-butylphenoxy)-4,4-bi A reaction product of bifinyl, which is mainly composed of finyldiphosphine, phosphorus trichloride and 2,4-di-tert-butylphenol (Hostanox (registered trademark) P-EPQ (registered trademark) P; manufactured by Clariant Japan Co., Ltd.). At least one selected from the group consisting of these is preferable. Phosphorus-based antioxidants may be used singly or in combination of two or more.
Examples of sulfur-based antioxidants include thioether-based antioxidants, specifically, distearyl-3,3-thiodipropionate (Irganox (registered trademark) PS802; manufactured by BASF Japan Ltd.), pentaeris Lityl tetrakis (3-laurylthiopropionate) (Sumilizer (registered trademark) TP-D; manufactured by Sumitomo Chemical Co., Ltd.), didodecyl (3,3'-thiodipropionate) (Irganox (registered trademark) PS800; BASF Japan Co., Ltd.), and at least one selected from the group consisting of these is preferable. Sulfur-based antioxidants may be used singly or in combination of two or more.
The content of the organic antioxidant is preferably 0.01 to 5.0% by mass, more preferably 0.01 to 2.0% by mass, in 100% by mass of the polyamide resin composition. , 0.02 to 1.5% by weight.
Examples of inorganic antioxidants include metal halide antioxidants. The metal halide antioxidant is a component that mainly imparts long-term heat resistance. A metal halide antioxidant is a compound of a halogen and a metal. Halogen includes fluorine, chlorine, bromine, iodine and the like. Examples of metals include Group 1 elements (alkali metals), Group 2 elements (alkaline earth metals), Group 3 to Group 12 elements (eg, transition metals), and the like. The metal in the metal halide is preferably a group 1 element (alkali metal) or a group 11 element (copper group) metal.
When the metal is a Group 1 element (alkali metal), the metal halide includes potassium iodide, potassium bromide, potassium chloride, sodium iodide, sodium chloride, and the like. In addition, when the metal is a group 11 element (copper group), the metal halide includes cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodide, Cupric iodide etc. are mentioned. The metal halide antioxidant is more preferably a mixture of cuprous iodide and potassium halide, or a mixture of cuprous bromide and potassium halide. A mixture or a mixture of cuprous bromide and potassium bromide is particularly preferred. A mixture of cuprous iodide and potassium iodide, or a mixture of cuprous bromide and potassium bromide, compared to the compounding amount (mass%) of cuprous iodide or cuprous bromide, potassium iodide Alternatively, it is preferable that the content of potassium bromide (% by mass) is large.
Furthermore, it is more effective to use nitrogen-containing compounds such as melamine, benguanamine, dimethylol urea and cyanuric acid in combination.
The inorganic antioxidants may be used singly or in combination of two or more.
The content of the inorganic antioxidant is preferably 0.01 to 5.0% by mass, more preferably 0.01 to 2.0% by mass, in 100% by mass of the polyamide resin composition. , 0.05 to 1.0% by weight.

Weather stabilizers (light stabilizers) include benzotriazole compounds, benzophenone compounds, triazine compounds, benzoate compounds, hindered amine compounds, phenyl salicylate compounds, cyanoacrylate compounds, malonic acid ester compounds, and oxalic acid anilide. system compounds and the like. The weathering agents may be used singly or in combination of two or more. Among them, hindered amine compounds are highly effective in scavenging radicals and suppressing photo-oxidation of resins, and can be used in combination with other weather resistance agents to enhance the effect of resins in suppressing ultraviolet absorption.

Further polyamide resins (excluding elastomer (A)) are not particularly limited, and include polyamide resins having the polyamide-forming units described above for elastomer (A). Specific examples of further polyamide resins (excluding elastomer (A)) include aliphatic polyamides (e.g., PA5, PA6, PA11, PA12, PA46, PA56, PA510, PA66, PA610, PA612, PA1010, PA1012, etc.) ), aromatic polyamides (e.g. PA4T, PA6T, PA9T, PA10T, PA6I, PAMXD6) and copolymers of two or more monomers forming said polyamides (e.g. PA6/66, PA6/69, PA6/610, PA6 /611, PA6/612, PA6/11, PA6/12, PA6/66/6I, PA6/66/12, PA6/66/610, PA6/69, PA6/66/612) and the like. Here, "PA" means "polyamide".

Additives (C) other than those described above can be appropriately selected from components usually added to resin compositions.
From the viewpoint of better mechanical properties, the resin composition preferably further contains a cross-linking agent. Further, when the resin composition contains an elastomer (A) having a mass ratio between the hard segment and the soft segment of 95/5 to 70/30, a cross-linking agent is added as the additive (C) from the viewpoint of permanent tensile set. It is preferable to use
Additives (C) may each be one component or a combination of two or more components.

〔Content〕
The content of each component with respect to the total mass of the resin composition is as follows.

The content of the elastomer (A) is 50.00-90.00% by mass. The content of the elastomer (A) is preferably 60.00 to 90.00% by mass from the viewpoint of mechanical properties and moldability.

The content of the modified polyethylene (B) is more than 0% by mass and 50.00% by mass or less, and from the viewpoint of tensile set, mechanical properties, and moldability, it is 5.00 to 50.00% by mass. Preferably, it is particularly preferably 10.00 to 50.00% by mass. When the resin composition further contains an additive (C), the total amount of (A) to (C) in the resin composition can be 100% by mass. Therefore, when the content of the modified polyethylene (B) is more than 0% by mass and less than 50.00% by mass, the resin composition further contains the additive (C) more than 0% by mass and less than 50.00% by mass. can be used. For example, when the content of modified polyethylene (B) is 5.00% by mass or more, the resin composition may further contain 5.00% by mass or more of additive (C). Moreover, the upper limit of the content of the modified polyethylene (B) can be a value obtained by subtracting the total content of the elastomer (A) and the additive (C) from 100.00% by mass.

The content of additive (C) is preferably 0 to 45.00% by mass. In addition, among the additives (C), the content of the further polyamide resin (excluding the elastomer (A)) is 0 mass from the viewpoint of not affecting the mechanical properties, molding processability and the effects of the present invention. % or more and less than 10.00 mass %, more preferably 0 mass % or more and less than 5.00 mass %, and particularly preferably 0 mass % or more and less than 3.00 mass %. Among the additives (C), the content of the weathering agent is preferably 0.01 to 5.00% by mass, more preferably 0.01 to 3.00, from the viewpoint of durability such as light resistance of the molded product. % by weight is particularly preferred. Among the additives (C), the content of the cross-linking agent is preferably 0.01 to 5.00% by mass, more preferably 0.01 to 4.00% by mass, from the viewpoint of tensile set and moldability. is particularly preferred. Among the additives (C), the content of the antioxidant is preferably 0.01 to 5.00% by mass from the viewpoint of appearance immediately after molding, deterioration over time, and maintenance of physical properties after heat deterioration. 0.01 to 3.00 mass % is particularly preferred. In the production of the elastomer (A) and the modified polyethylene (B), when a component corresponding to the additive (C) is used, the content of the component corresponding to the additive (C) is It is defined as the content of the component (C) with respect to the mass.

[Characteristics of resin composition]
For the resin composition, an ISO TYPE A-shaped 2 mm thick test piece prepared according to ISO 294-1 is subjected to 20% strain in a tensile tester according to JIS K 6273 in an environment of 23 ° C. and 50% relative humidity. And the tensile permanent strain when a 30-minute tensile permanent strain test is performed is preferably 30.0% or less, more preferably 29.5% or less, and further preferably 29.0% or less. preferable. From the viewpoint of better tensile permanent strain, the tensile permanent strain is preferably 5.0 to 30.0%, more preferably 5.0 to 29.5%, and 5.0 to 29.0. % is particularly preferred.

The above resin composition preferably has a tensile modulus of 100 MPa or more, measured according to ISO 527 on a 4 mm thick test piece of ISO TYPE A shape prepared according to ISO 294-1. From the viewpoint of mechanical properties, the tensile modulus is more preferably 100 to 800 MPa, particularly preferably 100 to 600 MPa.

When the resin composition has a tensile yield stress, it preferably has a tensile yield stress of 9 MPa or more when subjected to a tensile test under an atmosphere of 23°C based on ISO-527-1 and 2. Although some resins do not have a yield point and a tensile yield stress cannot be defined, it is also preferred that such resins have no tensile yield stress, as such resins are considered to be strain resistant.

The above resin composition can be designed to have appropriate fluidity according to the molding method. When the resin composition does not contain a cross-linking agent, it preferably has fluidity such that the flow length under the following conditions is 70 mm or more. Flow length measurement conditions are as follows. An injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., product name: PS40E, screw diameter : 26 mm), 20 pieces are injection molded under the following molding conditions: cylinder temperature 230°C, mold temperature 40°C, injection pressure 100 MPa, injection speed 38 mm/sec, injection time 4 seconds, cooling time 15 seconds. Using the final 10 molded products out of 20 molded products, the distance from the gate to the end of the flow is measured, and the average value is defined as the flow length.

[Method for producing resin composition]
The method for producing the resin composition is not particularly limited as long as it is a method capable of kneading each component. .

[Use of resin composition]
The above resin composition is not particularly limited, and can be used for producing molded articles using known methods. Molded articles containing the resin composition can also be used for automobile parts, electric parts, electronic parts, power tools, general industrial parts (packings, vibration-isolating rubbers, rubber hoses, etc.), machine parts, sporting goods, and the like.

[Method for producing molded article containing resin composition]
The method for producing a molded article containing the resin composition is not particularly limited, and a known method for producing a molded article containing a resin, such as injection molding, extrusion molding, blow molding, co-extrusion molding or multi-injection molding. is mentioned. The method for producing a molded article containing a resin composition is preferably injection molding from the viewpoint of efficiency in obtaining molded articles. It is particularly preferable that the method for producing a molded article using injection molding includes a step of injection molding the resin composition at a cylinder temperature of 200 to 250°C and a mold temperature of 30 to 50°C. The conditions of the method for manufacturing a molded article other than those described above can be appropriately set.

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples. The components used in Examples and Comparative Examples and methods for measuring physical properties of molded articles are shown below.

[Ingredients used]
1. Elastomer (A)
(Production of polyetheramide elastomer (PAE-1))
20.0 kg of 12-aminododecanoic acid (manufactured by UBE Corporation), adipic acid (Asahi Kasei Corporation 3.73 kg, ELASTAMINE (registered trademark) RT-1000 (manufactured by Huntsman, USA, number average molecular weight of about 1,000, XYX type triblock polyether diamine compound, formula (1), where x is about 3, y is About 9, z is about 2) 26.3 kg, 0.08 kg sodium hypophosphite, and 0.15 kg Irganox® 245 (BASF hindered phenolic antioxidant) were added. After the inside of the container was replaced with nitrogen, heating was started. After the temperature in the tank reached 230° C., the mixture was further heated and stirred for 5 hours, and the polymerization reaction was carried out while distilling off the reaction water out of the system. After completion of the reaction, a colorless and transparent polymer was extruded into water from the polymer outlet in the form of strands, and cut by a pelletizer to obtain 40 kg of PAE-1. The hard segment/soft segment (mass ratio) of PAE-1 is 47/53.

(Production of polyetheramide elastomer (PAE-2))
11.2 kg of 12-aminododecanoic acid (manufactured by UBE Corporation) and adipic acid (Asahi Kasei Co., Ltd.) are added to a 70 L pressure vessel equipped with a stirrer, thermometer, pressure gauge, nitrogen gas inlet, pressure regulator and polymer outlet company) 1.09 kg, ELASTAMINE (registered trademark) RT-1000 (manufactured by Huntsman in the United States, number average molecular weight of about 1,000, XYX type triblock polyether diamine compound, in formula (1), x is about 3, y of about 9 and z of about 2), 0.01 kg of sodium hypophosphite, and 0.06 kg of Irganox® 245 (a hindered phenolic antioxidant manufactured by BASF) were added. After the inside of the container was replaced with nitrogen, heating was started. After the temperature in the tank reached 230° C., the mixture was further heated and stirred for 5 hours, and the polymerization reaction was carried out while distilling off the reaction water out of the system. After completion of the reaction, a colorless and transparent polymer was extruded into water from the polymer outlet in the form of strands, and cut by a pelletizer to obtain 16 kg of PAE-2. The hard segment/soft segment (mass ratio) of PAE-2 is 62/38.

(Production of polyetheramide elastomer (PAE-3))
In a 70 L pressure vessel equipped with a stirrer, thermometer, pressure gauge, nitrogen gas inlet, pressure regulator and polymer outlet, 69.7 kg of 12-aminododecanoic acid (manufactured by UBE Corporation), adipic acid (Asahi Kasei Co., Ltd. company) 3.69 kg, ELASTAMINE (registered trademark) RT-1000 (manufactured by Huntsman, USA, number average molecular weight of about 1,000, XYX type triblock polyether diamine compound, in formula (1), x is about 3, y of about 9 and z of about 2), 0.11 kg of sodium hypophosphite, and 0.23 kg of Irganox® 245 (a hindered phenolic antioxidant manufactured by BASF) were added. After the inside of the container was replaced with nitrogen, heating was started. After the temperature in the tank reached 230° C., the mixture was further heated and stirred for 5 hours, and the polymerization reaction was carried out while distilling off the reaction water out of the system. After completion of the reaction, a colorless and transparent polymer was extruded into water from the polymer outlet in the form of strands, and cut by a pelletizer to obtain 90 kg of PAE-3. The hard segment/soft segment (mass ratio) of PAE-3 is 74/26.

(Production of polyetheramide elastomer (PAE-4))
44.0 kg of 12-aminododecanoic acid (manufactured by UBE Corporation), adipic acid (Asahi Kasei Co., Ltd., company) 0.75 kg, ELASTAMINE (registered trademark) RT-1000 (manufactured by Huntsman in the United States, number average molecular weight of about 1,000, XYX type triblock polyether diamine compound, in formula (1), x is about 3, y of about 9 and z of about 2), 0.10 kg of sodium hypophosphite, and 0.15 kg of Irganox® 245 (a hindered phenolic antioxidant manufactured by BASF) were added. After the inside of the container was replaced with nitrogen, heating was started. After the temperature in the tank reached 230° C., the mixture was further heated and stirred for 5 hours, and the polymerization reaction was carried out while distilling off the reaction water out of the system. After completion of the reaction, a colorless and transparent polymer was extruded into water from the polymer outlet in the form of strands, and cut by a pelletizer to obtain 40 kg of PAE-4. The hard segment/soft segment (mass ratio) of PAE-4 is 90/10.

In addition, a polyether polyester amide elastomer (Pebax (registered trademark) 6333, manufactured by ARKEMA) was used as the polyamide elastomer, and Hytrel 4047N (manufactured by Toray DuPont) was used as the polyether polyester elastomer.

2. Modified polyethylene (B)
Maleic anhydride-modified low-density polyethylene (F3000 (trade name), manufactured by Ube Maruzen Polyethylene Co., Ltd.) F3000 is a modified polyethylene obtained by modifying branched low-density polyethylene (LDPE) with maleic anhydride.
Maleic anhydride-modified ultra-high molecular weight polyethylene (manufactured by Mitsui Chemicals, Inc., Lubmer (registered trademark) LY1040 (intrinsic viscosity [η] measured in a decalinic acid solvent at 135 ° C.: 25 dl / g))
Maleic anhydride-modified linear low-density polyethylene (manufactured by Mitsui Chemicals, Admer NF567 (trade name))
In some examples, LLDPE (Evolue (registered trademark) SP0540 manufactured by Prime Polymer Co., Ltd.) was mixed and used as unmodified polyethylene.

3. Additive (C)
Weathering agent (BASF, Tinuvin 312)
Cross-linking agent (cyclic carbodiimide, manufactured by Teijin Limited, Carbosista (registered trademark) TCC-NP)
Antioxidant (hindered phenolic antioxidant, manufactured by BASF, Irganox (registered trademark) 245)

(Examples 1 to 18, Comparative Examples 1 to 6)
Elastomer (A), modified polyethylene (B), and additive (C) are melt-kneaded at 200 to 260° C. using a twin-screw kneader at the mass ratio (parts by mass) shown in Table 1, and Examples 1 to 18 are prepared. , to obtain resin compositions of Comparative Examples 1 to 6. Next, the obtained pellets of the resin compositions of Examples 1 to 18 and Comparative Examples 1 to 6 were injection molded at a cylinder temperature of 290 ° C. and a mold temperature of 80 ° C. to produce various test pieces and evaluate various physical properties. bottom. In Table 1, Elastomer (A) is the content of PAE-1 and the like excluding the antioxidant used in its production. Moreover, in Table 1, the antioxidant and its content in the additive (C) are the antioxidant used in the production of the elastomer (A) and its content.

[Tensile set]
A molded body (ISO TYPE A-shaped 2 mm-thick test piece) was obtained by injection molding. Tensile permanent strain was measured on the resulting molded body in accordance with JIS K 6273 using a tensile tester (strain 20%×30 min) under an environment of 23° C. and 50% relative humidity. In addition, when the tensile permanent strain was 30.0% or less, it was judged to be "excellent in tensile permanent strain".

[Mechanical properties]
(1) Tensile yield stress and tensile modulus Using the pellets, a type A test piece (thickness: 4 mm) was prepared based on ISO294-1, and a tensile test was performed under an atmosphere of 23°C based on ISO527-1 and 2. carried out. In the table below, those having no tensile yield stress are indicated as "-".
(2) Bending strength and bending elastic modulus Using the pellets, a type B type test piece (thickness: 4 mm) was prepared based on ISO294-1, and subjected to a bending test under an atmosphere of 23°C based on ISO178.
(3) Charpy Impact Strength Using the pellets, a type B type test piece (thickness: 4 mm) was prepared according to ISO294-1, and V-notched according to ISO 179/1eA in post-processing. A Charpy impact test was performed at a hammer capacity of 1 J under an atmosphere of 23°C.
(4) Fluidity The fluidity was evaluated by measuring the flow length of test pieces molded under the following molding conditions for each resin composition. An injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., product name: PS40E, screw diameter : φ 26 mm), 20 pieces were injection molded under the following molding conditions: cylinder temperature 230°C, mold temperature 40°C, injection pressure 100 MPa, injection speed 38 mm/sec, injection time 4 seconds, cooling time 15 seconds. Using the final 10 molded products out of 20 molded products, the distance from the gate to the end of the flow was measured, and the average value was taken as the flow length. It should be noted that, depending on the composition in which the cross-linking agent is blended, fluidity may not be necessary, and the item of fluidity of such a resin composition is indicated by "-".

In addition, the tensile yield stress is 9 MPa or more or has no tensile yield stress, the tensile elastic modulus is 100 MPa or more, the bending strength is 7 MPa or more, the bending elastic modulus is 100 MPa or more, and the Charpy impact strength was 40 KJ/m ² or more, it was judged to be "excellent in mechanical properties". A case satisfying all of the above five items was judged to be "excellent in mechanical properties", and a case satisfying three or more of the above five items was judged to be "slightly excellent in mechanical properties".

As is clear from the results in Tables 1-3, the resin compositions of Examples 1-18 were excellent in tensile set and mechanical properties. Further, it was found that by adding a cross-linking agent, a resin composition having better tensile set while maintaining mechanical properties can be obtained (Examples 5 and 11). On the other hand, since the resin compositions of Comparative Examples 1 to 6 did not contain the modified polyethylene (B), they were inferior in at least one of tensile set and mechanical properties.

Claims

A resin composition obtained by blending an elastomer (A) having a polyether structure as a soft segment and a modified polyethylene (B),
The modified polyethylene (B) has a density of 0.910 g/cm 3 or more and 0.925 g/cm 3 or less and/or a polyethylene having a weight average molecular weight (Mw) of 1 million or more. Modified with a derivative, a hydroxyl group-containing ethylenically unsaturated compound, an amino group-containing ethylenically unsaturated compound, or a vinyl group-containing organosilicon compound,
A resin composition containing 50.00 to 90.00% by mass of the elastomer (A) when the total of the elastomer (A) and the modified polyethylene (B) is 100% by mass.
The resin composition according to claim 1, wherein the elastomer (A) contains at least one selected from the group consisting of polyether polyamide elastomers and polyether polyester elastomers.
The resin composition according to claim 1, wherein the elastomer (A) has a hard segment to soft segment mass ratio of 95/5 to 30/70.
The resin composition according to claim 1, which contains 5.00 to 50.00% by mass of the modified polyethylene (B) in the resin composition.
The resin composition according to claim 1, further containing 0.01 to 5.00% by mass of a cross-linking agent in the resin composition.
The resin composition according to claim 1, further comprising 0% by mass or more and less than 10.00% by mass of a polyamide resin (excluding the elastomer (A)) in the resin composition.
An ISO TYPE A 2 mm thick test piece prepared according to ISO 294-1 was subjected to 20% strain and 30 minutes of tensile permanent stress under a 23°C, 50% relative humidity environment using a tensile tester based on JIS K 6273. 2. The resin composition according to claim 1, which has a permanent tensile strain of 29.5% or less when subjected to a strain test.
The resin composition according to claim 1, wherein an ISO TYPE A 4 mm thick test piece prepared according to ISO294-1 has a bending elastic modulus of 100 MPa or more measured according to ISO527.
A molded article containing the resin composition according to any one of claims 1 to 8.
A method for producing a molded product, comprising a step of injection molding the resin composition according to any one of claims 1 to 8 at a cylinder temperature of 200 to 250°C and a mold temperature of 30 to 50°C.