JP2019131795A - High molecular weight polymer composition - Google Patents

Abstract

To provide a tire application capable of enhancing grip performance by blending a specific hydrogenated styrenic resin as a tackifier resin to a rubber component, and further a damping rubber capable of exhibiting stably damping performance excellent in a high temperature range.SOLUTION: There is provided a high molecular weight polymer composition by blending 100 pts.wt. of (A) a high molecular weight polymer component consisting of (A-1) a conjugated diene rubber and/or (A-2) a thermoplastic elastomer, and 1 to 200 pts.wt. of (B) a hydrogenated styrenic resin having weight average molecular weight (Mw) in terms of polystyrene by a GPC (gel permeation chromatograph method of 500 to 10,000.SELECTED DRAWING: None

Description

  The present invention relates to a polymer composition useful for a tire tread, a vibration damping material, and the like, and particularly improves the wet grip performance without deteriorating other performance such as rolling resistance when used for a tire tread member. In addition, the present invention relates to a polymer composition useful for a vibration damping rubber that can exhibit excellent vibration damping performance in a wide temperature range, particularly in a high temperature range.

  Recently, in order to improve the safety of a vehicle on a wet road surface, it is required to improve the wet grip performance of a tire. However, conventional natural rubber, polyisoprene rubber and polybutadiene rubber have excellent physical properties and are widely used as a rubber component of tire members. However, since they generally have a low glass transition temperature, they are mainly used as rubber components. The rubber composition as a component has a low tan δ at 0 ° C., and it is known that the wet grip performance of the tire is lowered when used as a tread member of a tire.

  Here, a tire containing a low molecular weight polystyrene resin has been proposed (Patent Document 1). However, the low molecular weight polystyrene resin here is mainly used for adhesives for hot melts, and no specific formulation and examples as a tire composition are disclosed at all.

  A tire rubber composition in which a styrene-based thermoplastic elastomer and a tackifying resin are blended with a diene rubber containing a styrene-butadiene copolymer rubber has also been proposed (Patent Document 2). This rubber composition for tires is said to be able to achieve both improvement in initial grip performance and grip performance during traveling while maintaining wear resistance. However, even when these softeners are blended, the balance between the initial grip performance and other performance is not sufficient, and further improvement is required.

Further, an air provided with a tread composed of a rubber composition containing 0.5 parts by mass or more of silica and 5 parts by mass or more of resin with respect to 100 parts by mass of a rubber component containing styrene-butadiene rubber and, if necessary, butadiene rubber. An entering tire has been proposed (Patent Document 3).
And as this resin, there exists description that various resin and its hydrogenated substance may be sufficient (paragraph "0024" of the patent document).
However, in this patent document, there is no specific description of a hydrogenated product of a styrene resin as a resin.

  On the other hand, damping rubber is used in various fields as a material for absorbing unnecessary vibration. In particular, in recent years, it is frequently used as, for example, automobile parts and building materials. In that case, it is required to exhibit stable vibration absorbing performance in a wider temperature range, particularly in a high temperature range. In order to satisfy such requirements, conventionally, a rubber composition comprising an isobutylene-isoprene copolymer and a thermoplastic elastomer composed of a polystyrene-vinylpolyisoprene block copolymer has been proposed (Patent Document 4). . However, even in this rubber composition, no rubber damping rubber that is excellent in a high temperature region and can exhibit stable vibration damping performance has been reached.

Japanese Patent No. 6189864 JP 2017-101199 A JP 2017-190364 A JP 2007-70419 A

An object of the present invention is to solve the above-described problems of the prior art and to provide a high molecular weight polymer composition for tires that can improve wet grip performance without deteriorating other performances.
In addition, the present invention provides a vibration damping rubber that is superior in the high temperature range and can exhibit stable vibration damping performance by blending a hydrogenated styrene resin with the rubber component. is there.

The present invention comprises the following claims 1-11.
<Claim 1>
(B) GPC (Gel Permeation Chromatograph) polystyrene for 100 parts by weight of the polymer component comprising (A) (A-1) conjugated diene rubber and / or (A-2) thermoplastic elastomer. A polymer composition comprising 1 to 200 parts by weight of a hydrogenated styrene resin having a converted weight average molecular weight (Mw) of 500 to 10,000.
<Claim 2>
The polymer composition according to claim 1, wherein 5 to 500 parts by weight of (C) an inorganic filler is further blended with 100 parts by weight of component (A).
<Claim 3>
The polymer composition according to claim 1 or 2, further comprising 1 to 100 parts by weight of (D) a crosslinking agent based on 100 parts by weight of component (A).
<Claim 4>
(A-1) Conjugated diene rubber is natural rubber (NR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene rubber (NBR), polyisoprene rubber (IR), isobutylene. The polymer composition according to claim 1, which is at least one selected from the group of isoprene rubber (IIR).
<Claim 5>
(A-2) Thermoplastic elastomer is hydrogenated 1,2-polybutadiene, hydrogenated styrene-butadiene copolymer, hydrogenated styrene-isoprene copolymer, ethylene-propylene elastomer, styrene-grafted ethylene-propylene elastomer, thermoplasticity The polymer composition according to any one of claims 1 to 4, which is at least one selected from the group consisting of a polyester elastomer and an ethylene ionomer resin.
<Claim 6>
(B) The polymer composition according to any one of claims 1 to 5, wherein the hydrogenated styrene resin is obtained by hydrogenating a styrene resin and changing at least a part of an aromatic ring to an alicyclic ring. object.
<Claim 7>
(C) The inorganic filler is at least one fibrous filler selected from the group consisting of glass fiber, surface chemically treated glass fiber, carbon fiber, graphite, metal fiber, and titanium oxide, or a glass balloon or fly ash balloon. And at least one hollow filler selected from the group of silica balloons, or soft calcium carbonate, heavy calcium carbonate, surface-treated calcium carbonate, talc, magnesium hydroxide, mica, clay, barium sulfate, natural silicon, synthetic The polymer composition according to any one of claims 1 to 6, which is at least one selected from the group consisting of silicon, silica and carbon black.
<Claim 8>
(D) The polymer composition according to any one of claims 1 to 7, wherein the crosslinking agent is a sulfur-based crosslinking agent and comprises a combination of sulfur and a vulcanization accelerator.
<Claim 9>
A tire using the polymer composition according to any one of claims 1 to 8 as a tread member.
<Claim 10>
A vibration damping material comprising the polymer composition according to any one of claims 1 to 8.
<Claim 11>
A rubber belt using the polymer composition according to claim 1.

According to the present invention, a specific amount of a hydrogenated styrene resin is blended with a specific rubber component and / or elastomer component, and other performances such as rolling resistance are deteriorated by using it for a tread member of a tire. Thus, it is possible to provide a high molecular weight polymer composition for tires that can improve wet grip performance.
In addition, according to the present invention, a specific amount of hydrogenated styrene resin is blended with a specific rubber component and / or elastomer component, and the vibration damping performance is excellent in a temperature range that is significantly higher than that in the past. It is possible to provide a polymer composition for a vibration damping material that exhibits the above.

  The polymer composition of the present invention is relatively low with respect to 100 parts by weight of the polymer component comprising (A) (A-1) conjugated diene rubber and / or (A-2) thermoplastic elastomer. It is a polymer composition containing 1 to 200 parts by weight of (B) a hydrogenated styrene resin having a molecular weight, and (C) an inorganic filler, (D) a crosslinking agent, etc., if necessary. May be. Hereinafter, the polymer composition of the present invention will be described in detail according to constituent requirements.

Component (A) (A-1) Conjugated diene rubber (A-1) includes, for example, natural rubber (NR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene rubber ( Examples include conjugated diene polymers such as NBR), polyisoprene rubber (IR), and isobutylene-isoprene rubber (IIR), and all those that fall within the category of conjugated diene rubber are included.
(A-1) The polystyrene-converted weight average molecular weight (Mw) of the conjugated diene rubber is usually about 200,000 to 400,000.
Here, Mw is a value measured in terms of standard polystyrene based on the measured value by gel permeation chromatograph (GPC).
In the component (A), the proportion of the (A-1) conjugated diene rubber is 100 to 0% by weight, preferably 90 to 60% by weight [where (A-1) + (A-2) = 100% by weight. ].
Here, when (A-1) conjugated diene rubber is 100% by weight in component (A), the resulting composition is suitable for tire treads and the like, and in the case of 60-90% by weight. The obtained composition is preferable for tire sidewalls, vibration-damping rubbers, vibration-proofing rubbers, soundproofing materials and the like.

(A-2) Thermoplastic elastomer (A-2) Examples of the thermoplastic elastomer include hydrogenated 1,2-polybutadiene, hydrogenated styrene-butadiene copolymer, hydrogenated styrene-isoprene copolymer, and ethylene-propylene. Examples include elastomers, styrene-grafted ethylene-propylene elastomers, thermoplastic polyester elastomers, and ethylene ionomer resins, but in addition, all those belonging to the category of thermoplastic elastomers should be interpreted broadly.

In the component (A), the proportion of the (A-2) thermoplastic elastomer is 0 to 100% by weight, preferably 10 to 40% by weight [where (A-1) + (A-2) = 100% by weight]. It is.
Here, in the component (A), when the (A-2) thermoplastic elastomer is 0% by weight, the obtained composition is suitable for a tire tread and the like, and in the case of 10 to 40% by weight, The resulting composition is preferable for tire sidewalls, vibration-damping rubber, vibration-proof rubber, sound-proofing material, and the like.

(B) Hydrogenated styrene resin By adding (B) hydrogenated styrene resin to the composition of the present invention, a conventional terpene resin, petroleum resin, rosin resin, or terpene phenol resin is added. Compared with the method, wet grip performance, dry grip performance and durability can be improved in a well-balanced manner.
That is, (B) hydrogenated styrene resin reduces the double bonds and aromatic rings derived from styrene by hydrogenation, so that the dispersibility of the resin in the diene rubber is greatly increased and adsorbs sulfur of the crosslinking agent. Without accelerating the crosslinking of the rubber, making the crosslinking position between the rubber polymers uniform, and increasing the modulus of the rubber composition after vulcanization. Furthermore, since the rubber cross-linking becomes uniform and tight, durability and blowability are also improved.

  The hydrogenated styrene resin used in the present invention is obtained by hydrogenating a styrene resin to change at least a part of an aromatic ring to an alicyclic ring. The styrene resin can be obtained by addition polymerization of a styrene monomer or addition copolymerization of a styrene monomer and another monomer. The addition polymerization reaction can be performed according to a known method. For example, the addition polymerization can be performed by a solution polymerization method using a living anion polymerization catalyst, a method using a cationic polymerization catalyst, a method using a radical polymerization initiator, or the like. Examples of the styrene monomer include styrene, α-methylstyrene, β-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, and 4-phenylstyrene.

  The molecular weight of the hydrogenated styrene resin used in the present invention is 500 to 10,000, preferably 1,000 to 7,000 in terms of polystyrene-reduced weight average molecular weight (Mw) by gel permeation chromatography (GPC). More preferably, it is 1,500 to 5,000. When the weight average molecular weight is less than 500, the durability of the resulting composition is inferior. On the other hand, when the weight average molecular weight exceeds 10,000, the effect of improving the grip property of the obtained composition may be inferior.

The (B) hydrogenated styrene resin used in the present invention is obtained by hydrogenating an aromatic ring derived from a styrene monomer in the styrene resin. The method of hydrogenation is a conventionally known method and is not particularly limited.
For example, the (B) hydrogenated styrene resin used in the present invention is obtained by (co) polymerizing a styrene monomer and then hydrogenating it to change the unsaturated bond in the molecule to a saturated bond. Preferably there is. The hydrogenation reaction is performed by blowing hydrogen in the presence of a known hydrogenation catalyst. Examples of hydrogenation catalysts include cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, transition metal compounds such as titanocene dichloride / n-butyllithium, zirconocene dichloride / sec-butyllithium, tetrabutoxytitanate / dimethylmagnesium / alkyl. Homogeneous catalyst comprising a combination of metal compounds; heterogeneous metal catalyst such as nickel, palladium, platinum; nickel / silica, nickel / diatomaceous earth, nickel / alumina, palladium / carbon, palladium / silica, palladium / diatomaceous earth And a heterogeneous solid-supported catalyst in which a metal catalyst such as palladium / alumina is supported on a carrier.
The hydrogenation rate of the aromatic ring is not particularly limited, but is 0.1 to 100%, preferably 1 to 90%. When the hydrogenation rate of the aromatic ring is less than 0.1%, characteristics due to hydrogenation are not sufficiently exhibited.
Here, the hydrogenation rate (hydrogenation rate) of the aromatic ring is a value calculated by the following formula from the peak height of the absorbance derived from the styrene compound by IR (infrared spectrophotometer).
Hydrogenation rate (%) = {(C−D) / C} × 100
C: Absorbance peak height derived from an aromatic ring before hydrogenation D: Absorbance peak height derived from an aromatic ring after hydrogenation Note that (B) hydrogenated styrenic resin may be used alone. Two or more kinds may be used in combination.

  (B) The compounding quantity of hydrogenated styrene-type resin is 1-200 weight part with respect to 100 weight part of (A) component, Preferably it is 5-40 weight part. If the amount is less than 1 part by weight, the effect of improving the wet grip property is hardly exhibited.

(C) Filler The polymer composition of the present invention is mainly composed of (A) (A-1) conjugated diene rubber and / or (A-2) plastic elastomer and (B) hydrogenated styrene resin. However, in addition to this, a filler (C) can be further blended.
In the composition of the present invention, the reinforcing (C) filler is at least one fibrous material selected from the group consisting of glass fiber, surface chemically treated glass fiber, carbon fiber, graphite, metal fiber, and titanium oxide. Filler or at least one hollow filler selected from the group consisting of glass balloon, fly ash balloon, and silica balloon, or soft calcium carbonate, heavy calcium carbonate, surface treated calcium carbonate, talc, magnesium hydroxide, mica , Clay, barium sulfate, natural silicon, synthetic silicon, silica, and at least one selected from the group of carbon black.
These reinforcing fillers may be used alone or in combination of two or more.
(C) The compounding quantity of a filler is 5-500 weight part with respect to 100 weight part of (A) component which is a matrix component, Preferably it is 20-200 weight part. If it is less than 5 parts by weight, the effect of improving the strength and durability of the rubber composition is low. On the other hand, when the amount exceeds 500 parts by weight, the workability is poor and the dispersibility of the filler is lowered, so that uniform strength and durability cannot be maintained.

(D) Crosslinking agent (D) A crosslinking agent can be further mix | blended with the composition of this invention.
As the crosslinking agent (D) used in the present invention, for example, sulfur can be used. As sulfur, powdered sulfur, precipitated sulfur, insoluble sulfur, colloidal sulfur, surface-treated sulfur and the like can be used, and tetramethylthiuram disulfide, tetraethylthiuram disulfide and the like can be used as a compound that generates sulfur by heating.

  Examples of vulcanization accelerators used in combination with sulfur and compounds that generate sulfur by heating include tetramethylthiuram disulfide (TMTD), tetramethylthiuram monosulfide (TMTM), N-oxydiethylene-2-benzothiazolyl sulfenamide (OBS), N-cyclohexyl-2-benzothiazolyl sulfenamide (CBS), dibenzothiazyl sulfide (MBTS), 2-mercaptobenzothiazol (MBT), zinc di-n-butyldiocarbite (ZnBDC) ), Zinc dimethyldithiocarbite (ZnMDC), and the like.

  The compounding amount of the sulfur-based (D) crosslinking agent is 1 to 100 parts by weight, preferably 1 to 10 parts by weight with respect to 100 parts by weight of the component (A). When the amount is less than 1 part by weight, the degree of crosslinking is insufficient, and the hardness and rigidity after crosslinking are reduced. On the other hand, when the amount exceeds 100 parts by weight, the practicality of the rubber composition as an elastic body is impaired after crosslinking. Moreover, there is a risk that sufficient scorch time cannot be secured.

In addition, as the cross-linking agent (D), an organic peroxide can also be used.
As the organic peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5 Examples include -dimethyl-2,5-di (t-butylperoxy) hexyne-3, di-t-butyl peroxide, di-t-butylperoxy-3,3,5-trimethylcyclohexane and t-dibutyl hydroperoxide. . Of these, dicumyl peroxide, di-t-butyl peroxide and di-t-butylperoxy-3,3,5-trimethylcyclohexane are preferred.
The compounding quantity of an organic peroxide is 1-15 weight part normally with respect to 100 weight part of (A) component, Preferably it is about 1-10 weight part.

When an organic peroxide is used as the vulcanizing agent, it is preferable to use a vulcanization aid together. Vulcanization aids include quinone dioximes such as sulfur and p-quinonedioxime; acrylics such as ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate; allyls such as diallyl phthalate and triallyl isocyanurate; other maleimides Divinylbenzene and the like.
The amount of the vulcanization aid is usually 0.5 to 2 mol, preferably 0.5 to 1.5 mol, more preferably about equimolar to 1 mol of the organic peroxide used. Is desirable.

  Furthermore, the composition of the present invention can be preformed and crosslinked by electron beam irradiation. In the case of this crosslinking, an electron beam having an energy of 0.1 to 10 MeV is added to the preformed composition with an absorbed dose of usually 0.5 to 35 Mrad, preferably 0.5 to 20 Mrad, more preferably 1 to 1 Mrad. What is necessary is just to irradiate so that it may become 10 Mrad.

In addition to the components (A) to (D) described above, the composition of the present invention contains compounding agents usually used in the rubber industry, such as softeners, anti-aging agents, and coupling agents. It can select suitably in the range which does not injure the objective of invention, and can mix | blend within the range of a normal compounding quantity. As these compounding agents, commercially available products can be suitably used.
The composition of the present invention is prepared by blending various compounding agents appropriately selected as necessary, such as the above components (A) to (B) and further components (C) to (D), kneading, heating, extrusion. It can manufacture by doing.

  Moreover, the tire using the composition of this invention uses the high molecular polymer composition of this invention mentioned above for a tread member. The tire of the present invention can be produced by forming a raw tire using the above-mentioned composition as a tread member and vulcanizing the raw tire according to a conventional method. In addition, since the above-mentioned composition is used for the tread member of the tire of the present invention, the tire of the present invention has sufficiently secured other performance such as rolling resistance and particularly has wet grip performance. It is good. Moreover, as gas with which the tire of the present invention is filled, an inert gas such as nitrogen, argon, helium, etc. can be used in addition to normal or air having an adjusted oxygen partial pressure.

  Moreover, in order to produce a vibration damping material using the composition of the present invention, for example, components (A) to (D) and other compounding agents are generally used such as Banbury mixers, pressure kneaders, open rolls, etc. The uncrosslinked compound thus obtained is mixed using the mixing method used for the rubber compound, and the uncrosslinked compound thus obtained is formed into a sheet shape using a calendar, a roll, an extruder, etc. It is subjected to crosslinking in a heat medium such as air.

  Furthermore, in order to prepare a rubber belt using the polymer composition of the present invention, a predetermined amount of each component constituting the polymer composition of the present invention is used as usual using a kneader such as a Banbury mixer or a roll. After mixing, as a cover rubber for the belt, it may be charged simultaneously with the belt main body or separately into a mold or the like, and vulcanized at a predetermined temperature for curing.

  The crosslinking temperature of the composition of the present invention is 120 to 200 ° C., preferably 140 to 180 ° C. in hot air for crosslinking. At this time, it is not necessary to pressurize in particular, and crosslinking can be performed under atmospheric pressure.

<Tire tread evaluation>
EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not restrict | limited at all by these Examples.
<Synthesis of styrene resin a>
The flask was charged with 500 g of toluene and 15 g of aluminum chloride catalyst, stirred under a nitrogen stream, and 500 g of styrene was added dropwise over 1 hour. Meanwhile, the temperature in the flask was kept at 20 ° C. After completion of the dropping, the catalyst was removed by washing with water, and the resulting reaction oil was distilled under reduced pressure to distill off toluene, thereby obtaining 500 g of a resin. The weight average molecular weight was 2,500 and the softening point was 101 ° C.
<Synthesis of Hydrogenated Styrenic Resins (1) to (3)>
Hydrogenated styrene resin (1)
The autoclave was charged with 500 g of the styrene resin a obtained above, 1000 g of cyclohexane, and 10 g of powdered stabilized nickel catalyst, then sealed, and the atmosphere was replaced with nitrogen gas, and then hydrogen gas was introduced. did. And it heated with stirring, and when it became 150 degreeC, the pressure of hydrogen was 50 kg / cm < ² >, and it was made to react for 8 hours, maintaining the pressure at 50 kg / cm < ² > by supplementing the absorbed hydrogen. After the reaction, the catalyst was filtered and the solvent was distilled off under reduced pressure to obtain a hydrogenated styrene resin. The softening point was 117 ° C., and the hydrogenation rate of the aromatic ring was 75%.
Hydrogenated styrene resin (2)
The hydrogenation reaction was carried out for 4 hours in the same manner as the hydrogenated styrene resin (1). The softening point was 111 ° C., and the hydrogenation rate of the aromatic ring was 50%.
Hydrogenated styrene resin (3)
The hydrogenation reaction was carried out for 3 hours in the same manner as the hydrogenated styrene resin (1). The softening point was 107 ° C. and the hydrogenation rate of the aromatic ring was 25%.

<Synthesis of styrene resin b>
500 g of toluene and 15 g of aluminum chloride catalyst were charged into the flask, stirred under a nitrogen stream, and a mixture of 350 g of styrene and 150 g of α-methylstyrene was added dropwise over 1 hour. Meanwhile, the temperature in the flask was kept at 20 ° C. After completion of the dropping, the catalyst was removed by washing with water, and the resulting reaction oil was distilled under reduced pressure to distill off toluene, thereby obtaining 500 g of a resin. The weight average molecular weight was 1,660, and the softening point was 90 ° C.

<Synthesis of Hydrogenated Styrenic Resins (4) to (6)>
Hydrogenated styrene resin (4)
500 g of the styrenic resin b obtained above, 1,000 g of cyclohexane, and 10 g of powdered stabilized nickel catalyst were charged into an autoclave, which was then sealed and the atmosphere was replaced with nitrogen gas. Was introduced. And it heated with stirring, and when it became 150 degreeC, the pressure of hydrogen was 50 kg / cm < ² >, and it was made to react for 8 hours, maintaining the pressure at 50 kg / cm < ² > by supplementing the absorbed hydrogen. After the reaction, the catalyst was filtered and the solvent was distilled off under reduced pressure to obtain a hydrogenated styrene resin. The softening point was 106 ° C., and the hydrogenation rate of the aromatic ring was 75%.
Hydrogenated styrene resin (5)
The hydrogenation reaction was carried out for 4 hours in the same manner as the hydrogenated styrene resin (4). The softening point was 99 ° C., and the hydrogenation rate of the aromatic ring was 50%.
Hydrogenated styrene resin (6)
The hydrogenation reaction was carried out for 2 hours in the same manner as the hydrogenated styrene resin (4). The softening point was 94 ° C., and the hydrogenation rate of the aromatic ring was 25%.

Examples 1-6
Various chemicals used in Examples and Comparative Examples are shown below.
E-SBR (Emulsion polymerization SBR): manufactured by JSR 1502 Bonded styrene content 23.5% Mooney viscosity ML _{1 + 4} (100 ° C.) = 52 (M)
BR: JSR T700 cis1,4 bond 95% Mooney viscosity ML _{1 + 4} (100 ° C.) = 42 (M)
Carbon black: CABOT made show black _{N-330L HAF N 2 SA 75m} 2 / g DBP102ml / 100g
Silica: ULTRAIL VN3 N ₂ SA 175m ² / g made by EVONIK
Anti-aging agent: ANTAGE 6C (6PPD) manufactured by Kawaguchi Chemical, ANTAGE RD (TMQ) manufactured by Kawaguchi Chemical
Zinc oxide: Wako Pure Chemicals reagent purity 99%
Stearic acid: Wako Pure Chemicals reagent purity 95%
Silane coupling agent: SiVon bis (3-triethoxysilylpropyl) disulfide manufactured by EVONIK Tackifying resin: Hydrogenated styrene resins (1) to (6)
Sulfur powder: Wako Pure Chemical reagent purity 98%
Vulcanization accelerator: Kawaguchi Chemical Accel CZ (CBS), Accel D (DPG)

Among the blending contents shown in Tables 1 and 2, various chemicals excluding sulfur powder and a vulcanization accelerator were kneaded with a Toyo Seiki Lab Plast Mill 4C150 Banbury mixer. Subsequently, sulfur powder and a vulcanization accelerator were added and finished kneading to obtain an unvulcanized rubber.
The obtained unvulcanized rubber composition was press vulcanized at 150 ° C. for 30 minutes to produce vulcanized rubber compositions of Examples 1 to 6, and a viscoelasticity test and a tensile test were performed.

Comparative Examples 1-3
For comparison, all the tests were performed under the same conditions as in the examples except that YS resin PX1000, YS resin SX100, or SYLVARES SA85 was used as the tackifier resin.

<Viscoelasticity test>
The prepared test piece was cut into a width of 4.5 mm, a length of 40 mm, and a thickness of 0.5 mm, using a viscoelastic device DVE-V4 manufactured by UBM Co., Ltd., based on JIS K 6394, with a frequency of 10 Hz and an average strain of 3. The loss tangent tan δ at 0 ° C. and 60 ° C. was measured in the temperature range of −75 ° C. to 180 ° C. with 0%, strain amplitude ± 0.5, and distance between chucks of 10 mm. Larger tan δ at 0 ° C. indicates better wet grip characteristics, and smaller tan δ at 60 ° C. indicates lower rolling resistance and better fuel saving characteristics.

<Tensile test>
Using a No. 3 dumbbell-shaped test piece made of a vulcanized rubber composition, a tensile test was conducted in accordance with JIS K 6251 “Vulcanized Rubber and Thermoplastic Rubber-Determination of Tensile Properties”, and the elongation at break EB (% ) Was measured. It shows that a filler is disperse | distributed and it is excellent in rubber | gum strength, and it is excellent in durability, so that EB is large.

  From Table 1 and 2, the Example which mix | blended hydrogenated styrene-type resin (1)-(6) compared with the comparative example which mix | blended conventional resin (YS resin PX1000, YS resin SX100, SYLVARES SA85), and low fuel consumption. It can be seen that the performance and wet grip properties are improved.

<Vibration-proof rubber evaluation>
EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
Examples 7-12
Various chemicals used in Examples and Comparative Examples are shown below.
IIR: JSR BUTYL065 Mooney viscosity ML _{1 + 4} (125 ° C.) = 32 (M)
SIPS: Kuraray polystyrene-vinyl polyisoprene block copolymer Hibler 5127 Styrene content 20%
Tackifying resin: hydrogenated styrene resin (1) to (6)
Zinc oxide: Wako Pure Chemicals reagent purity 99%
Stearic acid: Wako Pure Chemicals reagent purity 95%
Vulcanizing agent: Actor Q (QO) manufactured by Kawaguchi Chemical
Vulcanization accelerator: Accelerator DM (MBTS) manufactured by Kawaguchi Chemical

Among the blending contents shown in Tables 3 and 4, various chemicals excluding the vulcanizing agent and the vulcanization accelerator were kneaded with a laboratory plastic mill 4C150 Banbury mixer manufactured by Toyo Seiki. Subsequently, a vulcanizing agent and a vulcanization accelerator were added, and finish kneading was performed to obtain an unvulcanized rubber.
The obtained unvulcanized rubber composition was press vulcanized at 150 ° C. for 30 minutes to produce vulcanized rubber compositions of Examples 7 to 12, and the dynamic viscoelasticity was measured.

Comparative Examples 4-6
For comparison, all were carried out under the same conditions as in the Examples except that YS Resin PX1000, YS Resin SX100, and SYLVARES SA85 were used as tackifying resins.

<Viscoelasticity test>
The prepared test piece was cut into a width of 4.5 mm, a length of 40 mm, and a thickness of 1 mm, using a viscoelastic device DVE-V4 manufactured by UBM Co., Ltd., at a frequency of 100 Hz, an initial strain of 0.2%, and a distance between chucks of 10 mm. It measured in the temperature range of -75 degreeC-180 degreeC. The results are shown in Tables 3 and 4. The higher the loss tangent tan δ and the wider the temperature range, the better the vibration damping characteristics.

  From Tables 3 and 4, the examples in which the hydrogenated styrene resins (1) to (6) were blended were more extensive than the comparative examples in which the conventional resins (YS resin PX1000, YS resin SX100, SYLVARES SA85) were blended. It can be seen that it has vibration damping characteristics in the temperature region.

The polymer polymer composition of the present invention is a tire polymer that can improve wet grip performance without deteriorating other performance such as rolling resistance, for example, when used for a tread member of a tire. It is useful as a composition and as a polymer composition for a vibration damping material that exhibits excellent vibration damping performance in a temperature range that is significantly higher than that of the prior art.
In addition, the polymer composition of the present invention includes oil hoses, fuel hoses, gas hoses, brake hoses, and other hoses, covers of these hoses, packing, gaskets, O-rings, belts, linings, oil seals, dusts. It is suitably used for manufacturing industrial parts such as boots, aircraft and automobile parts. In addition, automotive bumpers, exterior moldings, wind seal gaskets, door seal gaskets, trunk seal gaskets, roof side rails, emblems, inner panels, console boxes, and other interior and exterior skin materials, weather strips, leather seats, aircraft / Sealing materials for ships and inner and outer skin materials, civil engineering and architectural sealing materials, inner and outer skin materials and waterproof sheet materials, sealing materials for general machinery and equipment, etc. It can be widely used for general processed products such as equipment parts, electric wires, daily goods, and sports equipment.
Furthermore, the polymer composition of the present invention can be suitably used as a molded product for tire applications such as sidewalls and carcass, in addition to treads, and a molded product made of the composition of the present invention includes: Belts, hoses, anti-vibration rubber, vibration-damping materials, sound-insulating materials, wire covering materials, various footwear, toys, cutting board and (knives) grips and other household and miscellaneous goods, car mats, bumpers, mud guards, Inapane skins and side moldings, etc. Automotive interior / exterior products, automotive interior components in which the composition of the present invention is integrated with woven fabrics and / or nonwoven fabrics, backing materials used for tiles, car mats, carpets, medical treatments such as infusion tubes and syringes It can be suitably used for other industrial products such as products.
Furthermore, by using the composition of the present invention, such as products / members in fields requiring high cushioning properties, impact resistance or vibration control properties, such as in environments where large impacts are applied or in environments where intense vibrations are involved. Molded products, seismic isolation rubber for homes, handle grips for motorcycles and bicycles, steps, grips for power tools, pneumatic rock drills for road construction, grips for consolidation lumers, golf clubs, tennis rackets, baseball bats, etc. Can be suitably used for gripping various sports equipment accompanied by hitting, and for absorbing impact generated when contacting with the road surface of a walking cane. Further, it can be suitably used for preventing excessive repulsion of game balls in a ball game machine.

Claims (11)

  (B) GPC (Gel Permeation Chromatograph) polystyrene for 100 parts by weight of the polymer component comprising (A) (A-1) conjugated diene rubber and / or (A-2) thermoplastic elastomer. A polymer composition comprising 1 to 200 parts by weight of a hydrogenated styrene resin having a converted weight average molecular weight (Mw) of 500 to 10,000.   The polymer composition according to claim 1, wherein 5 to 500 parts by weight of (C) an inorganic filler is further blended with 100 parts by weight of component (A).   The polymer composition according to claim 1 or 2, further comprising 1 to 100 parts by weight of (D) a crosslinking agent based on 100 parts by weight of component (A).   (A-1) Conjugated diene rubber is natural rubber (NR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene rubber (NBR), polyisoprene rubber (IR), isobutylene. The polymer composition according to claim 1, which is at least one selected from the group of isoprene rubber (IIR).   (A-2) Thermoplastic elastomer is hydrogenated 1,2-polybutadiene, hydrogenated styrene-butadiene copolymer, hydrogenated styrene-isoprene copolymer, ethylene-propylene elastomer, styrene-grafted ethylene-propylene elastomer, thermoplasticity The polymer composition according to any one of claims 1 to 4, which is at least one selected from the group consisting of a polyester elastomer and an ethylene ionomer resin.   (B) The polymer composition according to any one of claims 1 to 5, wherein the hydrogenated styrene resin is obtained by hydrogenating a styrene resin and changing at least a part of an aromatic ring to an alicyclic ring. object.   (C) The inorganic filler is at least one fibrous filler selected from the group consisting of glass fiber, surface chemically treated glass fiber, carbon fiber, graphite, metal fiber, and titanium oxide, or a glass balloon or fly ash balloon. And at least one hollow filler selected from the group of silica balloons, or soft calcium carbonate, heavy calcium carbonate, surface-treated calcium carbonate, talc, magnesium hydroxide, mica, clay, barium sulfate, natural silicon, synthetic The polymer composition according to any one of claims 1 to 6, which is at least one selected from the group consisting of silicon, silica and carbon black.   (D) The polymer composition according to any one of claims 1 to 7, wherein the crosslinking agent is a sulfur-based crosslinking agent and comprises a combination of sulfur and a vulcanization accelerator.   A tire using the polymer composition according to any one of claims 1 to 8 as a tread member.   A vibration damping material comprising the polymer composition according to any one of claims 1 to 8. A rubber belt comprising the polymer composition according to claim 1.