JP2003277548A - Thermoplastic elastomer composition and molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic olefinic elastomer which develops excellent slidability and abrasion resistance, and to provide a molding made from the same. <P>SOLUTION: The thermoplastic elastomer composition is one comprising (A) an olefin resin, (B) at least one rubber selected from an olefin rubber (B1) and a styrene rubber (B2), and (C) a polymer prepared by grafting segments comprising a vinyl polymer onto a thermoplastic elastomer, wherein the content of component A is 60-5 wt.% based on the total amount of components A and B, the content of component B is 40-95 wt.% based the total amount of components A and B, and the content of component C is 0.1-10 pts.wt. per 100 pts.wt. total of components A and B. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic elastomer composition. More specifically, the present invention relates to a thermoplastic elastomer composition having excellent slidability and abrasion resistance, and a molded product made of the composition.

[0002]

2. Description of the Related Art Thermoplastic elastomers such as polyolefin thermoplastic elastomers can be processed by an ordinary thermoplastic resin molding machine, can be recycled, and are flexible, so that they can be used in console boxes and instrument panel skins. It has come to be used for various parts such as automobile interior parts such as and car exterior parts such as wind moldings. When these parts are used, the parts are rubbed with each other and the hands and parts are rubbed with each other. Therefore, the parts are required to have slidability and abrasion resistance. Due to the appearance, the required level of slidability and wear resistance is increasing. As a countermeasure, for example, a thermoplastic elastomer composition in which a fluororesin or a fatty acid amide is mixed with a thermoplastic elastomer has been proposed.

[0003]

However, the slidability and abrasion resistance of the above-mentioned thermoplastic elastomer composition have not been sufficiently satisfactory. Under such circumstances,
The problem to be solved by the present invention is to provide a thermoplastic elastomer composition having excellent slidability and abrasion resistance, and a molded article made of the composition.

[0004]

That is, the first aspect of the present invention relates to a thermoplastic elastomer composition containing the following components (A) to (C). (A): Olefin resin (B): At least one rubber selected from olefin rubber (B1) and styrene rubber (B2) (C): A segment composed of a vinyl polymer is grafted to a thermoplastic elastomer The polymer according to the second aspect of the present invention relates to a molded article including the thermoplastic elastomer composition.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The olefin resin (A) used in the present invention is ethylene, propylene, 1-butene,
1 to 2 carbon atoms such as 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene
A polymer containing repeating units derived from one or more of 0 olefins according to JIS K-71
The maximum temperature of the melting peak measured according to 21 is 80 ° C.
The above is a polymer having a flexural modulus of 50 MPa or more measured according to JIS K-7203.

Examples of the olefin resin (A) include ethylene homopolymer, propylene homopolymer, 1-
Butene homopolymer, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, propylene-1-butene copolymer, propylene- 1-hexene copolymer, propylene-1-octene copolymer, ethylene-propylene-1-butene copolymer, ethylene-propylene-1-hexene copolymer, ethylene-propylene-
Examples thereof include 1-octene copolymers, which may be used alone or in combination of two or more. Moreover, these can be manufactured by a well-known method.

Among the olefin resins (A), a propylene polymer containing a repeating unit derived from propylene is preferable from the viewpoint of increasing the heat resistance of the molded product. Examples of the propylene-based polymer include propylene homopolymer, propylene-ethylene random copolymer, propylene-ethylene block copolymer and the like. When a propylene homopolymer is used, a propylene homopolymer having high crystallinity is preferable in order to obtain a molded product having high rigidity. On the other hand, when a propylene-ethylene random copolymer is used, a propylene-ethylene random copolymer having a low ethylene unit content and high crystallinity is preferable for obtaining a molded product having high rigidity, and a molded product having low rigidity. In order to obtain the above, a propylene-ethylene random copolymer having a large ethylene unit content and low crystallinity is preferable. The propylene-ethylene block copolymer is composed of a first segment and a second segment, the first segment is a propylene homopolymer part, the second segment is a propylene-ethylene random copolymer part block copolymer There is a propylene-ethylene random copolymer having a different ethylene content as the first segment or the second segment. Further, the content of the propylene-ethylene random copolymer part as the second segment is 30.
A reactor olefin-based thermoplastic elastomer (R-TPO) having a content of not less than wt% may be used.

The melt flow rate (MFR) of the olefin resin (A) is preferably 0.1 to 0.1 from the viewpoint of enhancing the strength of the molded product and further enhancing the appearance of the molded product.
150 g / 10 minutes, more preferably 1-100 g
/ 10 minutes. Here, the melt flow rate (MFR) of the olefin resin (b) is JIS K-7210.
According to (1999), temperature 230 ° C, load 21.18
Measured in N.

The component (B) used in the present invention is at least one rubber selected from olefin rubber (B1) and styrene rubber (B2).

The olefin rubber (B1) is ethylene,
Repeats derived from one or more olefins having 2 to 10 carbon atoms such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. A polymer containing units, containing no repeating units derived from vinyl aromatic compounds and having a Shore A of 99 or less as measured according to ASTM D2240. The olefin rubber (B1) may contain a repeating unit derived from a monomer other than an olefin, for example, a repeating unit derived from a conjugated diene, a non-conjugated diene or a triene. . As a conjugated diene,
1,3-Butadiene, 2-methyl-1,3-butadiene (isoprene), 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like are mentioned, and as the non-conjugated diene, 1,4 Chain non-conjugated dienes such as -hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, 7-methyl-1,6-octadiene; cyclohexadiene, di Cyclopentadiene, methyltetrahydroindene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene. Cyclic non-conjugated dienes such as
-Diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-
Propenyl-2,2-norbornadiene, 1,3,7-
Octatriene, 1,4,9-decatriene and the like can be mentioned. These are used alone or in combination of two or more.

Examples of the olefin rubber (B1) include ethylene-propylene copolymer and ethylene-1-.
Butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-propylene-1-butene copolymer, ethylene-propylene-1-hexene copolymer, ethylene-propylene-1 -Octene copolymer, ethylene-propylene-5-ethylidene-2
-Norbornene copolymer and propylene-1-butene copolymer are mentioned, and these are used alone or in combination of two or more. Moreover, these can be manufactured by a well-known method.

Among the olefin rubbers (B1), ethylene rubbers containing repeating units derived from ethylene are preferable from the viewpoint of enhancing the strength of the molded product, and ethylene-α-olefin copolymers and ethylene-α are preferred. An olefin-non-conjugated diene copolymer is more preferable, and an ethylene-α-olefin polymer is still more preferable. Where α-
As the olefin, propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene are preferable, and propylene is more preferable, from the viewpoint of easy availability. As the non-conjugated diene, 5-ethylidene-2-norbornene and dicyclopentadiene are preferable from the viewpoint of easy availability.

The content of the repeating unit derived from the α-olefin of the ethylene rubber is preferably 10 to 50% by weight from the viewpoint of enhancing the flexibility of the molded product,
It is more preferably 20 to 40% by weight.

The content of the repeating unit derived from the non-conjugated diene in the ethylene-α-olefin-non-conjugated diene copolymer is usually 5 to 40 in terms of iodine value.

As the olefin rubber (B1), an oil-extended olefin rubber to which a mineral oil softener is added may be used. When the oil-extended olefin rubber is used, the content of the extending oil is usually 20 per 100 parts by weight of the olefin rubber.
~ 150 parts by weight. As the mineral oil-based softening agent, it is possible to use an extension oil that is usually used for adjusting an oil-extended rubber. Minutes (average molecular weight of 300 to 1500, pour point of 0 ° C. or lower) can be used. Of these, paraffinic mineral oils are preferred.

The Mooney viscosity (ML _{1 + 4} 100 ° C.) at 100 ° C. of the olefin rubber (B1) is preferably 5 to 150 from the viewpoint of enhancing the strength of the molded product and further enhancing the appearance of the molded product. , More preferably 20 to 10
It is 0. Here, the olefin rubber (B1) 100 ° C
Mooney viscosity (ML _{1 + 4} 100 ℃) of ASTMD-
Measured at 100 ° C according to 927-57T. When an oil-extended olefin rubber is used as the olefin rubber (B1), the Mooney viscosity of the oil-extended olefin rubber is the Mooney viscosity of the olefin rubber.

Styrene rubber (B2) is an olefin,
A copolymer of a vinyl aromatic compound and at least one monomer selected from dienes and trienes, wherein AST
A polymer having a Shore A of 99 or less measured according to MD2240. As the olefin, ethylene,
Examples thereof include olefins having 2 to 10 carbon atoms such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. As the diene, 1,3-butadiene,
2-methyl-1,3-butadiene (isoprene), 1,
Conjugated dienes such as 3-pentadiene and 2,3-dimethyl-1,3-butadiene; 1,4-hexadiene, 1,6
-Octadiene, 2-methyl-1,5-hexadiene,
6-methyl-1,5-heptadiene, 7-methyl-1,
Chain-like non-conjugated dienes such as 6-octadiene; cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinylnorbornene, 5-ethylidene-
2-norbornene, 5-methylene-2-norbornene,
Examples thereof include cyclic non-conjugated dienes such as 5-isopropylidene-2-norbornene and 6-chloromethyl-5-isopropenyl-2-norbornene. Examples of the triene include 2,3-diisopropylidene-5-norbornene and 2-ethylidene-3-isopropylidene-5-
Examples thereof include norbornene, 2-propenyl-2,2-norbornadiene, 1,3,7-octatriene, and 1,4,9-decatriene. Examples of the vinyl aromatic compound include styrene, p-methylstyrene, α-methylstyrene and the like, and among these, styrene is preferable from the viewpoint of easy availability. Further, the styrene rubber (B2) may be subjected to hydrogenation treatment.

Among the styrene rubbers (B2), from the viewpoint of increasing the strength of the molded product, at least one polymer block derived from a vinyl aromatic compound is contained and at least a polymer block derived from a diene is contained. A block polymer having one block and / or a hydrogenated product of the polymer is preferable. As the diene, a conjugated diene is preferable, and 1,3-butadiene and isoprene are more preferable, from the viewpoint of easy availability.

The content of the repeating unit derived from the vinyl aromatic compound of the styrene rubber (B2) is preferably 10 to 50% by weight from the viewpoint of flexibility and strength of the molded product.
And more preferably 20 to 40% by weight.

As the styrene rubber (B2), an oil-extended styrene rubber to which a mineral oil softener is added may be used. When the oil-extended styrene-based rubber is used, the content of the extending oil is usually 20 to 40 per 100 parts by weight of the styrene-based rubber.
0 parts by weight. As the mineral oil-based softening agent, it is possible to use an extension oil usually used for adjusting an oil-extended rubber, and for example, a high boiling point distillation oil of petroleum such as paraffin-based mineral oil, naphthene-based mineral oil, and aromatic-based mineral oil. Min (average molecular weight 30
0-1500, and the pour point is 0 ° C. or lower). Of these, paraffinic mineral oils are preferred.

The component (C) is a polymer obtained by grafting a segment composed of a vinyl polymer to a thermoplastic elastomer. The thermoplastic elastomer exhibits the properties of rubber-like elastomer at normal temperature, and melts and flows out like resin at high temperature. The thermoplastic elastomer is a blend type that mixes a soft component and a hard component, a block type that has a soft segment and a hard segment in the molecule, and a block molecule that has a soft segment molecule and a hard segment molecule and a soft segment and a hard segment molecule during polymerization. There is a polymerization type in which
Examples of the thermoplastic elastomer include olefin-based thermoplastic elastomer, styrene-based thermoplastic elastomer, polyester-based thermoplastic elastomer, urethane-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, and the like. A plastic elastomer and a styrene-based thermoplastic elastomer are preferable. Examples of the olefin-based thermoplastic elastomer include a blend type of an olefin-based resin and an olefin-based rubber, a block type such as an ethylene-hydrogenated butadiene-ethylene copolymer, and a polymerization type such as a reactor TPO. Examples thereof include blend types of olefin rubber and styrene rubber, and block types such as styrene-hydrogenated butadiene-styrene copolymer.

The vinyl polymer forming the segment composed of the vinyl polymer of the component (C) is a polymer obtained by polymerizing one kind or two or more kinds of vinyl monomers. The vinyl-based monomer is a non-olefin-based monomer and includes methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, and acrylic acid n.
-Butyl, isobutyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, glycidyl acrylate, aminoethyl acrylate, aminopropyl acrylate, propylaminoethyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, Dimethylaminopropyl acrylate, hydroxyethyl acrylate, 2-hydroxypropyl acrylate,
3-hydroxypropyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, glycidyl methacrylate, aminoethyl methacrylate, aminopropyl methacrylate, propyl methacrylate Aminoethyl, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate,
Unsaturated carboxylic acid esters such as dimethylaminopropyl methacrylate, hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, dimethyl fumarate, dibutyl fumarate, dilauryl itaconate, and glycidyl itaconate; acrylics Acid, methacrylic acid, fumaric acid, maleic anhydride, itaconic acid, itaconic anhydride, bicyclo (2,
Unsaturated carboxylic acids such as 2,1) -5-heptene-2,3-dicarboxylic acid; acrylamides such as acrylamide, methacrylamide, N, N-dimethylacrylamide; vinylamines such as vinylpyrrolidone and vinylimidazole; acrylonitrile; Vinyl cyanides such as methacrylonitrile; vinyl esters such as vinyl acetate, vinyl propionate, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl stearate, vinyl trifluoroacetate; styrene, nucleus-substituted styrene, α
Examples thereof include vinyl aromatic compounds such as substituted styrenes (α-methylstyrene, α-ethylstyrene, etc.).

As the component (C), acrylic acid-methyl acrylate copolymer, acrylic acid-ethyl acrylate copolymer, acrylic acid-propyl acrylate copolymer, acrylic acid-n-butyl acrylate copolymer Coalescence, methyl acrylate homopolymer, ethyl acrylate homopolymer, methacrylic acid-methyl methacrylate copolymer, methacrylic acid-ethyl methacrylate copolymer, methacrylic acid-propyl methacrylate copolymer, methacrylic acid-methacrylic acid Acid n-butyl copolymer, methyl methacrylate homopolymer,
Examples thereof include ethyl methacrylate homopolymers.

The content of the vinyl polymer segment in the component (C) is usually 1 to 99% by weight, preferably 5 to 95% by weight. From the viewpoints of slidability and abrasion resistance, it is preferable that the content is high, but if the content is too high, the strength of the molded product may decrease.

As the component (C), those produced by a known production method, for example, the production method described in JP-A-6-256440 may be used, or a commercially available product, for example, manufactured by NOF Corporation. Nofalloy (trade name) may be used.

The content of the component (A) and the component (B) in the thermoplastic elastomer composition is preferably 100% by weight based on the total amount of the component (A) and the component (B). The content is 60 to 5% by weight, the content of the component (B) is 40 to 95% by weight, and more preferably the content of the component (A) is 40 to 10% by weight. ) Content is 60 to 90% by weight. Ingredient (A)
If the content of is too large (the amount of the component (B) is too small), the flexibility of the molded article may decrease, and if the content of the component (A) is too small (the amount of the component (B) is too large), The heat resistance of the molded product may decrease.

The content of the component (C) in the thermoplastic elastomer composition is 1 total amount of the component (A) and the component (B).
The amount is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 00 parts by weight. From the viewpoints of slidability and abrasion resistance, it is preferable that the content of the component (C) is large, but if the content of the component (C) is too large, the strength of the molded product may decrease.

The thermoplastic elastomer composition of the present invention comprises
From the viewpoint of further improving the slidability and wear resistance, it is preferable to add a lubricant. Examples of the lubricant include fatty acid lubricants such as fatty acids and fatty acid amides; silicone lubricants such as silicone oil and silicone rubber.

The thermoplastic elastomer composition of the present invention comprises
Inorganic fillers (talc, calcium carbonate, calcined kaolin, etc.), organic fillers (fiber, wood flour,
Cellulose powder, etc.), antioxidants (phenolic, sulfur, phosphorus, lactone, vitamin, etc.),
Weather resistance stabilizer, UV absorber (benzotriazole-based, tridiamine-based, anilide-based, benzophenone-based, etc.),
You may mix | blend additives, such as a heat stabilizer, a light stabilizer (hindered amine type, a benzoate type), an antistatic agent, a nucleating agent, and a pigment.

As the method for preparing the thermoplastic elastomer composition of the present invention, known methods are used, and the components (A) to
The component (C) and, if necessary, the additives may be dry blended or may be melt-kneaded by heating. As the kneading device, a continuous kneader and / or a batch kneader can be used. As the continuous kneader, a single-screw extrusion kneader,
Examples thereof include a twin-screw kneading extruder, and among these, a twin-screw kneading extruder is preferable. Examples of the batch type kneader include a kneader and a Banbury mixer. Among them, the Banbury mixer is preferable.

The thermoplastic elastomer composition of the present invention comprises
Various molding methods such as injection molding, extrusion molding, hollow molding, vacuum molding, and calendar molding are used to mold various molded products, and among these, it is suitable for injection molding.

The molded article made of the thermoplastic elastomer composition of the present invention can be used for parts such as automobiles, trains, ships, home electric appliances and buildings; stationery; medical instruments. In particular, it is suitable for automobile interior parts such as armrests, console boxes, shift lever knobs, slide covers, brake covers, airbag covers, door covers, instrument panel covers, and assist grips.

[0033]

EXAMPLES Next, the present invention will be explained by examples. [1] Evaluation method A flat plate having a thickness of 2 mm and a size of 150 mm × 90 mm was molded using an injection molding machine at a cylinder temperature of 220 ° C. and a mold temperature of 50 ° C., and then evaluated. (1) Sliding property Using a slipping tester manufactured by HEIDON, a load of 500 g was applied and the dynamic frictional force with Kanakin 3 was measured. The dynamic friction coefficient was calculated from the measured dynamic friction force and the load to evaluate the slidability. The smaller the dynamic friction coefficient, the better the slidability. (2) Abrasion resistance A load of 500 g was applied using a vibration abrasion tester, and the surface of the test piece was rubbed 5000 times with Kanakin No. 3. The gloss of the surface of the test piece after the abrasion test was measured, and the abrasion resistance was evaluated according to the following criteria. In addition, gloss is JIS K-7105 (19
81), a digital variable angle gloss meter (model UGV-5D manufactured by Suga Test Instruments Co., Ltd.) under the conditions of an incident angle and a light receiving angle of 60 degrees.
(P type) was used for the measurement. ◯: The gloss exceeds 20%. X: The gloss is 20% or less.

[2] Raw material (A) olefin resin Noblen AZ161C1 manufactured by Sumitomo Chemical Co., Ltd.
(Polypropylene) (B) Olefin rubber Sumitomo Chemical Co., Ltd. Esplen SPO N0391
(Ethylene-butene copolymer) (C) Graft polymer NOFALLOY KA532 manufactured by NOF CORPORATION

Example 1 The olefin resin and olefin rubber having the blending amounts shown in Table 1 were charged into a twin-screw extrusion kneader and the rotation speed was 253 rpm.
Cylinder temperature 180 ℃ -200 ℃, feed amount 50k
After kneading and granulating at g / h, the kneaded product and the graft thermoplastic elastomer are put into a single-screw kneading extruder, and the rotation speed is 57.
Kneading and granulation were performed at rpm and a cylinder temperature of 200 ° C to 220 ° C. Table 1 shows the evaluation results of the obtained thermoplastic elastomer composition.

Comparative Example 1 The olefin resin and the olefin rubber having the blending amounts shown in Table 1 were charged into a twin-screw extrusion kneader, and the rotation speed was 253 rpm.
Cylinder temperature 180 ℃ -200 ℃, feed amount 50k
Kneading and granulation were performed at g / h. Table 1 shows the evaluation results of the obtained thermoplastic elastomer composition.

[0037]

[Table 1]

[0038]

As described above, according to the present invention, it is possible to provide a thermoplastic elastomer composition having excellent slidability and abrasion resistance. Further, the thermoplastic elastomer composition of the present invention can be excellent in strength, flexibility and heat resistance.
Therefore, the thermoplastic elastomer composition of the present invention can be used for parts such as automobiles, trains, ships, home electric appliances and buildings; stationery; medical instruments.

Continued front page    F-term (reference) 4F071 AA10 AA14 AA15X AA20                       AA21X AA22 AA77 AF22                       AF26 AF27 AF45 AH03 AH07                       AH10 AH12 AH19 BA01 BB05                       BC07                 4J002 AE054 BB03W BB03X BB04W                       BB05X BB12W BB12X BB14W                       BB14X BB15W BB15X BB17W                       BB17X BB19W BN033 BN063                       BN173 BN213 BP01X BP02W                       FD010 FD170 GB00 GC00                       GL00 GN00 GQ00

Claims (5)

[Claims] 1. A thermoplastic elastomer composition containing the following components (A) to (C). (A): Olefin resin (B): At least one rubber selected from olefin rubber (B1) and styrene rubber (B2) (C): A segment composed of a vinyl polymer is grafted to a thermoplastic elastomer Polymer 2. The total amount of component (A) and component (B) is 100.
The content of the component (A) is 60 to 5% by weight, the content of the component (B) is 40 to 95% by weight, and the content of the component (B) is 40 to 95% by weight.
To 100 parts by weight of the total amount of the components (A) and (B),
The thermoplastic elastomer composition according to claim 1, wherein the content of the component (C) is 0.1 to 10 parts by weight. 3. A molded article comprising the thermoplastic elastomer composition according to claim 1. 4. An automobile interior part made of the thermoplastic elastomer composition according to claim 1. 5. A shift lever knob, armrest or assist grip made of the thermoplastic elastomer composition according to claim 1.