Sole member for footware

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a footwear bottom material containing a hydrogenated diene-based copolymer as a polymer component, which is particularly excellent in wear resistance and also has good appearance, flexibility, solvent resistance and mechanical properties.

【0002】

[Conventional technology]

The block copolymer of the aromatic vinyl compound and the conjugated diene can be molded as a thermoplastic elastomer by the same processing technique as that of a general thermoplastic resin. At that time, the footwear bottom material has advantages such as having an appropriate rubber elasticity without particularly requiring a compounding of a cross-linking agent and a heat-cross-linking step which are usually required in the processing of general-purpose rubber. It is manufactured by injection molding.

【0003】

However, the footwear bottom material thus molded has a drawback that the flow mark of the block copolymer at the time of molding is poor, so that flow marks are generated on the surface of the footwear bottom material and the appearance is deteriorated. In order to improve the appearance of footwear bottom material, 1,2-polybutadiene is blended with a block copolymer of an aromatic vinyl compound and a conjugated diene. When this method is used, the poor appearance of the footwear bottom material is remarkably improved, but there is a problem that the wear resistance, which is an important performance as the footwear bottom material, is lowered. Further, polyamide resins and thermoplastic polyurethane resins are used as footwear bottom materials because they have excellent wear resistance, but these resins are expensive and have a problem of deterioration of physical properties due to hydrolysis.

【0004】

[Problems to be Solved by the Invention]

An object of the present invention is to provide a footwear bottom material having excellent wear resistance and good appearance, flexibility, solvent resistance, and mechanical properties.

【0005】

[Means for Solving the Invention]

According to the present invention, the following footwear bottom material is provided to achieve the above object of the present invention. That is, the footwear bottom material of the present invention has the following configuration. 1. The double bond of the conjugated diene portion of the conjugated diene polymer is saturated by 80% or more. A footwear bottom material characterized by containing a hydrogenated diene-based polymer as a polymer component. 2. The conjugated diene-based polymer is (A) a polybutadiene block having a vinyl bond content of 30% or less, and (B) (i) a polymer block of a conjugated diene having a vinyl bond content of more than 30%, or (ii) vinyl. That the aromatic compound component content is less than 50% by weight, and the vinyl bond content of the conjugated diene component portion exceeds 30%, at least containing a random copolymer block of the conjugated diene and the vinyl aromatic compound. The footwear bottom material according to 1 above. 3. The footwear bottom material according to 1 or 2 above, which further contains a polyolefin resin in an amount of 99% by weight or less based on the total amount of the hydrogenated diene polymer.

【0006】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the footwear bottom material of the present invention will be described in more detail. [1] Hydrogenated diene-based copolymer The hydrogenated diene-based copolymer contained in the footwear bottom material of the present invention as a polymer component is saturated with a double bond of 80% or more, preferably 90% or more of the conjugated diene portion of the conjugated diene-based polymer. It is something that is. Examples of the conjugated diene-based polymer include the following. (1) A homopolymer of conjugated diene. (2) Random copolymer of conjugated diene and aromatic vinyl compound. (3) A block copolymer containing a polymer block of an aromatic vinyl compound and a polymer block of a conjugated diene. (4) A block copolymer containing a polymer block of an aromatic vinyl compound and a random copolymer block of a conjugated diene / aromatic vinyl compound. (5) A block copolymer containing a polymer block of a conjugated diene and a copolymer block of a conjugated diene / aromatic vinyl compound. (6) A block copolymer containing a polymer block of conjugated diene and a tapered block composed of an aromatic vinyl compound component and a conjugated diene component in which the aromatic vinyl compound component gradually increases. (7) A block copolymer containing a random copolymer block of a conjugated diene / aromatic vinyl compound and a tapered block composed of an aromatic vinyl compound component and a conjugated diene component in which the aromatic vinyl compound component gradually increases. (8) A block copolymer containing a polybutadiene block having a vinyl bond content of 30% or less and a polymer block of conjugated diene having a vinyl bond content of more than 30%. (9) A polybutadiene block having a vinyl bond content of 30% or less, and a random copolymer block of a conjugated diene having a vinyl bond content of more than 30% in the conjugated diene component portion and a vinyl aromatic compound (50 vinyl aromatic compound components). Block copolymer containing less than% by weight). (10) Polybutadiene block having a vinyl bond of 30% by weight or less, a polymer block of conjugated diene having a vinyl bond content of more than 30%, and a vinyl aromatic compound polymer block having a vinyl aromatic compound component content of more than 50% by weight. A block copolymer containing and. (11) A polybutadiene block having a vinyl bond of 30% or less, and a random copolymer block of a conjugated diene having a vinyl bond content of more than 30% in the conjugated diene component portion and a vinyl aromatic compound (50 weight by weight of the vinyl aromatic compound component). A block copolymer containing (containing less than%) and a vinyl aromatic compound polymer block (containing a vinyl aromatic compound component in an amount of more than 50% by weight).

【0007】

Among them, the preferred conjugated diene-based polymer is the block copolymer of (8) to (11) above. That is, (A) a polybutadiene block having a vinyl bond content of 30% or less, preferably 25% or less (hereinafter, also referred to as "block (A)"), and (B) (i) a vinyl bond content of more than 30%. The conjugated diene polymer block is preferably 35% or more, or (ii) the vinyl aromatic compound component content is less than 50% by weight, preferably 1 to 40% by weight, and the vinyl bond content of the conjugated diene component portion is 30%. Contains at least a random copolymer block of a conjugated diene of 35% or more and a vinyl aromatic compound (hereinafter, the blocks of (i) and (ii) are collectively referred to as "block (B)"). It is a block copolymer that is used. A particularly preferable conjugated diene-based copolymer is a vinyl aromatic compound polymer containing 50% by weight or more, preferably 70% by weight or more of a vinyl aromatic compound in addition to the above blocks (A) and block (B). It is a block copolymer containing a block (C) (hereinafter, also referred to as "block (C)"). This corresponds to the block copolymers (10) and (11) above.

【0008】

The conjugated diene of the conjugated diene polymer is 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3. -Hexadiene, 4,5-diethyl-1,3-octadene, 3-butyl-1,3-octadiene, chloroprene and the like can be mentioned. 1,3-butadiene, isoprene, and 1,3-pentadiene are preferable, and 1,3-butadiene and isoprene are particularly preferable, from the viewpoint of obtaining a hydrogenated diene-based polymer that can be used industrially and has excellent physical characteristics. .. Examples of aromatic vinyl compounds include styrene, α-methylstyrene, p-methylstyrene, t-butylstyrene, divinylbenzene, N, N-dimethyl-p-aminoethylstyrene, and N, N-diethyl-p-aminoethyl. Examples include styrene and vinylpyridine. Of these, styrene and α-methylstyrene are preferable.

【0009】

The conjugated diene-based polymer may be a polymer in which the polymer molecular chain is extended or branched via a coupling residue by the use of a coupling agent. Examples of the coupling agent used in this case include diethyl adipate, divinylbenzene, methyldichlorosilane, silicon tetrachloride, butyltrichlorosilicon, tetrachlorotin, butyltrichlorotin, dimethylchlorosilicon, tetrachlorogermanium, 1,2-. Examples thereof include dibromoethane, 1,4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidized flaxseed oil, tolylene diisocyanate, and 1,2,4-benzenetriisocyanate.

【0010】

The hydrogenated diene-based polymer contained in the footwear bottom material of the present invention is saturated with a double bond of 80% or more, preferably 90% or more of the conjugated diene portion of the conjugated diene-based polymer. If it is less than 80%, weather resistance, heat resistance, etc. will decrease, which is not preferable.

【0011】

As the hydrogenated diene copolymer, a modified hydrogenated diene copolymer having at least one functional group selected from an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group and an epoxy group is used. You may. Further, a blend of the unmodified hydrogenated diene-based copolymer and the modified hydrogenated diene-based copolymer at an arbitrary ratio can also be used as the hydrogenated diene-based copolymer.

【0012】

Further, as the hydrogenated diene-based polymer, one obtained by hydrogenating a blend of two or more kinds of pre-hydrogenated conjugated diene-based polymers or a blend of two or more kinds of hydrogenated diene-based polymers can be used. it can.

【0013】

The weight average molecular weight of the hydrogenated diene polymer is preferably 10,000 to 700,000, more preferably 50,000 to 600,000 as a polystyrene-equivalent value measured by the GPC method. When the weight average molecular weight is less than 10,000, the hydrogenated diene polymer is easily blocked when pelletized, and the mechanical strength of the footwear bottom material is lowered when the following polyolefin resin is used in combination. On the other hand, if it exceeds 700,000, the fluidity, processability, etc. are inferior, which is not preferable.

【0014】

Hydrogenated diene-based polymers are, for example, JP-A-3-72512, page 4, upper right column, lines 13 to 6, page 6, lower left line 1, JP-A-5-27135, page 3, left column, lines 42 to 7. Page Right column 19 lines, Japanese Patent Application Laid-Open No. 5-271377 Page 3 Left column 36 lines-7 pages Right column 31 lines, Japanese Patent Application Laid-Open No. 3-128957 Page 4 Upper right column 8th line 6th page Lower left column It can be manufactured by the method described in the 7th line, JP-A-2-1333406, page 4, lower left column, line 13 to page 5, lower left column, line 10.

【0015】

The hydrogenated diene polymer is preferably contained in the footwear bottom material in an amount of 10 to 90% by weight, more preferably 15 to 85% by weight.

【0016】

[2] Polyolefin-based resin The polyolefin-based resin that can be used in combination with the hydrogenated diene-based polymer as the polymer component of the footwear bottom material of the present invention is one or more monoolefins of one or more of the high-pressure method, medium-pressure method, and low-pressure method. It is a crystalline resin produced by the polymerization method according to the above method, and is preferably polyethylene, polypropylene, or polybutene-1. These preferred polyolefin resins may be homopolymers or copolymers with the following comonomer.

【0017】

Preferred comonomer for producing the above-mentioned preferable polyolefin-based resin includes, for example, ethylene (excluding the case where the main polymer is polyethylene), propylene (excluding the case where the main polymer is polypropylene), butene-1 (excluding the case where the main polymer is polypropylene). Linear α-olefins such as pentene-1, hexene-1, hepten-1, octene-1 (unless the main polymer is polybutene-1), 4-methylpentene-1, 2-methylpropene- Branched α-olefins such as 1,3-methylpentene-1,5-methylhexene-1,4-methylhexene-1, 4,4-dimethylpentene-1; acrylic acids that can be polymerized with these α-olefins. , Monocarboxylic acids such as methacrylic acid, ethanecrylic acid, crotonic acid, dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid and their monoesters, acrylic acids such as methyl methacrylate, methyl acrylate and ethyl acrylate or methacrylic acid. Vinyl esters of esters, vinyl acetate and saturated carboxylic acids such as vinyl propionate; aromatic vinyl compounds such as styrene, α-styrene, p-methylstyrene; maleic anhydride, itaconic anhydride, citraconic anhydride, aconitic anhydride Acid anhydrides such as; α, β-unsaturated nitriles such as acrylonitrile and methacrylonitrile; diene monomers such as 1,4-hexadiene, dicyclopentadiene, etilidennorbornene; and acrylamide, methacrylicamide, maleimide; and the like.

【0018】

These copolymerizable comonomer may be used alone or in combination of two or more. The amount of these copolymerization components is preferably 30% by weight or less, more preferably 20% by weight or less. The mode of the copolymer when these are copolymerized is not particularly limited, and may be, for example, a random type, a block type, a graft type, or a mixed type thereof.

【0019】

Preferred copolymers used as the polyolefin-based resin include propylene-ethylene copolymer, propylene-butene-1 copolymer, butene-1-ethylene copolymer, propylene-ethylene-butene-1 copolymer, and the like. Ethylene-butene-1 copolymer, ethylene-hexene-1 copolymer, ethylene-octene-1 copolymer, ethylene-vinyl acetate copolymer, ethylene-ethylacrylate copolymer, ethylene-ethyl methacrylate copolymer , Ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-n butyl acrylate copolymer. These polyolefin resins can be used alone or in combination of two or more.

【0020】

Further, the olefin-based polymer is at least one functional group selected from functional groups such as an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group and an epoxy group in the olefin-based polymer described above. It may be a modified polyolefin polymer having a group introduced therein.

【0021】

The polyolefin-based resin is used so as to occupy 0 to 99% by weight, preferably 10 to 90% by weight, and more preferably 15 to 85% by weight of the total amount of the polyolefin-based resin and the hydrogenated diene-based polymer. If the polyolefin-based resin is blended in an amount of more than 99% by weight, the flexibility is reduced.

【0022】

If necessary, the polymer component constituting the footwear bottom material of the present invention can be crosslinked by a conventionally known method, such as sulfur cross-linking, peroxide cross-linking, metal ion cross-linking, silane cross-linking, and resin cross-linking. Further, the footwear bottom material obtained by molding by injection molding or the like can be subjected to post-crosslinking such as electron beam cross-linking and water cross-linking, if necessary.

【0023】

The footwear bottom material of the present invention can be molded by a molding method such as injection molding or press molding, and injection molding is particularly preferable. In this case, the hydrogenated diene polymer and the polyolefin resin can be kneaded in advance with an extruder or the like to form a composition, which can be molded by an injection molding machine, or a predetermined amount of the hydrogenated diene polymer. , Polyolefin-based resin can be weighed and mixed directly by injection molding machine. When the composition is kneaded in advance before injection molding, for example, a known kneader such as various extruders, a Banbury mixer, a kneader, and a roll, and a kneader combining them are used to obtain a melt-kneaded composition. be able to. Further, each component may be mixed all at once, or any component may be premixed in advance and then the remaining components may be mixed.

【0024】

Further, the footwear bottom material of the present invention can also be obtained by foam injection molding, foam press molding, or the like. In this case, the hydrogenated diene polymer, the polyolefin resin, and the foaming agent can be kneaded in advance with an extruder or the like to form a composition, which can be foam-molded with an injection molding machine. It is also possible to use an injection molding machine to foam-mold a polymer or polyolefin resin that has been kneaded in advance with an extruder or the like to form a composition, and then weighed and mixed a predetermined amount of foaming agent. It is also possible to directly foam-mold a fixed amount of a hydrogenated diene polymer, a polyolefin resin, and a foaming agent by measuring and mixing them with an injection molding machine.

【0025】

The foot material of the present invention contains various additives such as an antiaging agent, a heat stabilizer, a weather resistant agent, a metal deactivator, an ultraviolet absorber, a light stabilizer, and a stabilizer such as a copper damage inhibitor, if necessary. , Antibacterial / antifungal agent, dispersant, softener, plasticizer, crystal nucleating agent, flame retardant, tackifier, foaming aid, colorant such as titanium oxide and carbon black, metal powder such as ferrite, glass fiber , Inorganic fibers such as metal fibers, organic fibers such as carbon fibers and aramid fibers, composite fibers, inorganic whiskers such as potassium titanate whiskers, glass beads, glass balloons, glass flakes, asbestos, mica, calcium carbonate, talc, silica, Fillers such as calcium silicate, hydrotalcite, kaolin, diatomaceous soil, graphite, pebbles, evo powder, cotton flocs, cork powder, barium sulfate, fluororesin, polymer beads, or mixtures thereof, polyolefin wax, cellulose powder, It can be used by blending a filler such as rubber powder, a low molecular weight polymer, or the like. Further, a rubbery polymer, a hydrogenated diene-based polymer having a hydrogenation ratio of less than 80% of the conjugated diene portion, a thermoplastic resin and the like can be appropriately blended to the extent that the effects of the present invention are not impaired. In particular, EPM, EPDM, oil-expanded EPDM, EVA, ethylene-based copolymers obtained by metallocene-based polymerization catalysts, and functional groups such as acid anhydride groups, carboxyl groups, hydroxyl groups, amino groups, isocyanate groups, and epoxy groups. May be blended with a modified product or the like which has been modified by introducing.

【0026】

[Example]

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. The parts and% in Examples and Comparative Examples are based on weight unless otherwise specified. In addition, various measurements in Examples and Comparative Examples were based on the following methods. (1) Content of bound vinyl aromatic compound 679 cm^-1Based on the absorption of the phenyl group of, it was measured by infrared analysis. (2) Vinyl bond content of conjugated diene component It was calculated by the Morero method using infrared analysis. (3) Hydrogenation rate of conjugated diene component Using carbon tetrachloride as a solvent, 90MHz,¹Calculated from 1 H-NMR spectrum. (4) Weight average molecular weight of hydrogenated diene polymer The weight average molecular weight (hereinafter, also referred to as "molecular weight") was determined in terms of polystyrene using gel permeation chromatography (GPC).

【0027】

(5) Molded appearance The appearance of injection molding was visually evaluated according to the following criteria. : The appearance is good. X: It has pearl luster and flow marks, and the appearance is poor, such as a rough surface. (6) DIN wear The measurement was performed according to DIN53516. The measurement conditions are a particle size of 60, a drum rotation of 40 rpm, a load of 10 N, and a moving distance of 40 m. (7) Hardness JIS A hardness was measured according to JIS K 6301. (8) Tensile strength Measured in accordance with JIS K 6301. (9) Solvent resistance The appearance of the molded product after being immersed in n-heptane at 23 ° C for 24 hours was visually judged according to the following criteria. : No change was observed. Δ: Slightly swollen. ×: Swelled.

【0028】

The various components used in the formulations shown in Examples and Comparative Examples are as follows. (Hydrogenated Diene Polymer) A hydrogenated diene polymer having the structure shown in Table 1 below.

【0029】

[table 1]

<img file="JP2001197902A_D0001.tif" />*: Vinyl bond content of butadiene component BD: Butadiene ST: Styrene [0030]

(Polyolefin resin) P-1; Low-density polyethylene manufactured by Japan Polychem Corporation, trade name: LJ900N, MFR: 45g / 10 minutes (190 ° C, 2.16kg load) P-2; Ethylene-octene-1 copolymer manufactured by Dow Chemical, trade name: ENGAGE8402, MFR = 30g / 10 minutes (190 ° C, 2.16kg load) P-3; Propylene-ethylene random copolymer manufactured by Japan Polyolefins Co., Ltd., trade name: MD772H, MFR: 30g / 10 minutes (230 ° C, 2.16kg load) [0031]

(Rubber polymer) Oil exhibition EPDM; Made by Nippon Synthetic Rubber Co., Ltd., ethylene / propylene / ethylidene norbornene copolymer rubber, trade name: EP504EC, Mooney viscosity (ML1 + 4,100 ° C) 87 [0032]

Examples 1 to 14, Comparative Examples 1 to 3 Hydrogenated diene-based polymers and polyolefin-based resins were melt-kneaded with a uniaxial extruder according to the compounding formulations shown in Tables 2 to 5 to obtain a uniform mixture, which was then subjected to injection molding for evaluation. The results of the physical property evaluation are shown in Tables 2-5. From the results of Examples 1 to 14 shown in Tables 2 to 4, the composition of the present invention has a molded appearance, wear resistance, tensile strength, and flexibility (hardness) as compared with Comparative Examples 1 and 2 shown in Table 5. ), It can be seen that it has an excellent balance of solvent resistance and is suitable as a footwear bottom material. In addition, Examples 12 and 13 shown in Table 4 are cases where two kinds of hydrogenated diene polymers are used, and Example 14 is a combination of a hydrogenated diene polymer and an oil-extended EPDM which is a rubbery polymer. However, all of them have an excellent balance of wear resistance, flexibility, molding processability, solvent resistance, and mechanical properties.

【0033】

On the other hand, Comparative Example 1 is an example in which polyethylene is used as a polymer component and has high hardness and is inferior in flexibility, and Comparative Example 2 is an example in which polyethylene and EPDM are used as polymer components. It is inferior in solvent resistance, and all of them have poor physical balance and are not suitable as footwear bottom materials.

【0034】

[Table 2]

<img file="JP2001197902A_D0002.tif" />【0035】

[Table 3]

<img file="JP2001197902A_D0003.tif" />【0036】

[Table 4]

<img file="JP2001197902A_D0004.tif" />【0037】

[Table 5]

<img file="JP2001197902A_D0005.tif" />【0038】

[Effect of the invention]

The footwear sole material of the present invention has good appearance, abrasion resistance, flexibility, solvent resistance, and mechanical properties, and is therefore preferably used for bottom materials such as top lifts and sports shoes.