JP2018002861A - Hydrocarbon resin and elastomer composition for tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrocarbon resin providing an elastomer composition for tire which is excellent in workability and has excellent balance between rolling resistance and wet grip performance.SOLUTION: A hydrocarbon resin contains an aliphatic monomer unit and an aromatic monomer unit, where a content in the aromatic monomer unit of a monomer unit having such a structure two or more cyclic structures in the aromatic monomer unit are bonded to each other is 50 mass% or more, the number average molecular weight (Mn) is in a range of 400-3,000, the weight average molecular weight (Mw) is in a range of 700-6,000, the Z average molecular weight (Mz) is in a range of 1,500-20,000, a ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight is in a range of 1.0-4.0, a ratio (Mz/Mw) of the Z average molecular weight to the weight average molecular weight is in a range of 1.0-4.0, and a softening point is in a range of 80-150°C.SELECTED DRAWING: None

Description

  The present invention relates to a hydrocarbon resin that provides a tire elastomer composition having excellent workability and excellent balance between rolling resistance and wet grip performance.

  In recent years, automobile tires are strongly required to have low fuel consumption due to environmental problems and resource problems, while, for example, improvement in wet grip properties is required from the viewpoint of safety. The cross-linked product of the elastomer composition in which silica is added to the elastomer as a filler has a lower rolling resistance when a tire is configured than the cross-linked product of the elastomer composition in which carbon black is mixed. Therefore, a tire excellent in fuel efficiency can be obtained by constituting a tire using a crosslinked product of an elastomer composition blended with silica.

  However, even when silica is blended with a conventional elastomer, the affinity between the elastomer and silica is insufficient, and these are easily separated, resulting in poor processability of the elastomer composition before crosslinking. The elastomer cross-linked product obtained by cross-linking this has a problem that the rolling resistance is insufficient when a tire is constituted.

  Further, in Patent Document 1, for the purpose of improving the rolling resistance and wet grip property of a tire, a specific amount of a softening agent having a specific structure and a specific amount of a hydrocarbon resin having a specific structure are mixed with an elastomer. It is disclosed.

JP 2010-241965 A

  In the softener and hydrocarbon resin having a specific structure described in Patent Document 1, when a tire is manufactured from an elastomer cross-linked product obtained by adding these, it certainly improves both wet grip properties and rolling resistance characteristics. However, there is a problem that it is still insufficient.

  The present invention has been made in view of the above problems, and mainly provides a hydrocarbon resin that provides a tire elastomer composition having excellent workability and excellent balance between rolling resistance and wet grip performance. Objective.

  As a result of diligent investigations on hydrocarbon resins that give a tire elastomer composition that has excellent workability and excellent balance between rolling resistance and wet grip performance, a structure in which two or more cyclic structures are combined A hydrocarbon resin containing a monomer unit having a predetermined ratio and having a predetermined characteristic such as a number average molecular weight within a predetermined range is improved in workability and rolling resistance with respect to the tire elastomer composition. And the present invention has been completed by finding that it is involved in a well-balanced improvement of both the wet grip performance and the wet grip performance.

  Thus, according to the present invention, a hydrocarbon resin containing an aliphatic monomer unit and an aromatic monomer unit, wherein a structure in which two or more cyclic structures of the aromatic monomer units are bonded is provided. The content of the monomer unit in the aromatic monomer unit is 50% by mass or more, the number average molecular weight (Mn) is in the range of 400 to 3000, and the weight average molecular weight (Mw) is 700 to It is in the range of 6000, the Z average molecular weight (Mz) is in the range of 1500 to 20000, and the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) is in the range of 1.0 to 4.0. The ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw) is in the range of 1.0 to 4.0, and the softening point temperature is in the range of 80 ° C. to 150 ° C. A resin is provided.

  The hydrocarbon resin is 1,3-pentadiene monomer unit 10% by mass to 60% by mass, C 4-6 alicyclic monoolefin monomer unit 1% by mass to 30% by mass, C 4 -C 8 acyclic monoolefin monomer unit 1% by mass to 50% by mass, alicyclic diolefin monomer unit 0% by mass to 10% by mass, and the above aromatic monomer unit 0.1% by mass to It is preferable to contain 50 mass%.

  The monomer having a structure in which two or more cyclic structures are bonded is at least one selected from the group consisting of naphthalene compounds, fluorene compounds, biphenyl compounds, anthracene compounds, phenanthrene compounds, indene compounds, and benzothiophene compounds. It is preferable.

  Moreover, according to this invention, the elastomer composition for tires characterized by including at least 1 type of elastomer, at least 1 type of filler, and the above-mentioned hydrocarbon resin is provided.

  The filler is preferably silica.

  INDUSTRIAL APPLICABILITY The present invention has an effect of providing a hydrocarbon resin that provides a tire elastomer composition excellent in workability and having an excellent balance between rolling resistance and wet grip performance.

The present invention relates to a hydrocarbon resin and a tire elastomer composition using the same.
Hereinafter, the hydrocarbon resin and the tire elastomer composition of the present invention will be described in detail.

A. Hydrocarbon resin The hydrocarbon resin of the present invention is a hydrocarbon resin containing an aliphatic monomer unit and an aromatic monomer unit, and two or more cyclic structures are bonded to each other among the aromatic monomer units. The content of the monomer unit having the above structure in the aromatic monomer unit is 50% by mass or more, the number average molecular weight (Mn) is in the range of 400 to 3000, and the weight average molecular weight (Mw). Is in the range of 700 to 6000, the Z average molecular weight (Mz) is in the range of 1500 to 20000, and the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) is in the range of 1.0 to 4.0. The ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw) is in the range of 1.0 to 4.0, and the softening point temperature is in the range of 80 ° C to 150 ° C. To do.

According to the present invention, the hydrocarbon resin contains an aliphatic monomer unit and an aromatic monomer unit, and the monomer unit has a structure in which two or more cyclic structures are bonded among the aromatic monomer units. Body unit at a predetermined ratio, and a predetermined number average molecular weight, weight average molecular weight, Z average molecular weight, ratio of weight average molecular weight to number average molecular weight, ratio of Z average molecular weight to weight average molecular weight, softening point temperature, etc. By having the characteristics, it is possible to obtain an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance.
Here, by using the hydrocarbon resin, it is not clear why the elastomer composition for a tire excellent in workability and excellent in the balance of rolling resistance and wet grip performance can be obtained. It is guessed as follows.
That is, by using a hydrocarbon resin containing a predetermined proportion of monomer units having a structure in which two or more cyclic structures are combined as an aromatic monomer unit, and having the predetermined characteristics In the hydrocarbon resin of the present invention, the weight average molecular weight (Mw) and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight (Mn) are appropriately low, and the softening point temperature is appropriately high. Can do.
For this reason, when the hydrocarbon resin of the present invention is mixed with an elastomer or the like to form an elastomer composition, it becomes excellent in compatibility with the elastomer, and for example, uniform mixing with the elastomer becomes easy. Therefore, the obtained elastomer composition has excellent processability, and the obtained elastomer composition has a low loss coefficient tan δ at 60 ° C. and a loss coefficient tan δ at 0 ° C. of the crosslinked product. Can be reasonably high.
As a result, when a tire is manufactured using such an elastomer composition, it is possible to form a tire having an excellent balance between rolling resistance and wet grip performance.
From the above, by using the above hydrocarbon resin, it is possible to obtain an elastomer composition for tires which is excellent in workability and excellent in balance between rolling resistance and wet grip performance.

The hydrocarbon resin of the present invention contains an aliphatic monomer unit and an aromatic monomer unit.
Hereinafter, the aliphatic monomer unit and the aromatic monomer unit constituting the hydrocarbon resin of the present invention will be described in detail.

1. Aromatic monomer unit The aromatic monomer unit in the present invention includes a monomer unit having a structure in which two or more cyclic structures are bonded.

(1) Monomer unit having a structure in which two or more cyclic structures are bonded As a monomer constituting a monomer unit having a structure in which two or more cyclic structures are bonded, normally, One having at least one group carbon-carbon unsaturated bond and a structure in which two or more cyclic structures are bonded is suitably used. Here, as a structure in which two or more cyclic structures are bonded, any structure that includes one or more aromatic rings among the two or more cyclic structures may be used. It may contain a ring and a non-aromatic ring structure.

  The aliphatic carbon-carbon unsaturated bond is not particularly limited as long as it has radical polymerizability, and a vinyl group can be preferably used.

The aliphatic carbon-carbon unsaturated bond may be included as a part of the cyclic structure like a vinylene group included in a five-membered ring of indene, or a vinyl group included in 1-vinylnaphthalene. In this way, it may be bonded to the ring structure.
In the present invention, it is particularly preferable that the aliphatic carbon-carbon unsaturated bond is included as a part of the cyclic structure. This is because the polymerizability, the molecular weight, and the controllability of the softening point are excellent.
In addition, when an aliphatic carbon-carbon unsaturated bond is contained as a part of the cyclic structure, the cyclic structure is a non-aromatic ring structure.

In the case where the aliphatic carbon-carbon unsaturated bond is included as a part of the cyclic structure, the number of carbons of the cyclic structure including the aliphatic carbon-carbon unsaturated bond as a part thereof has desired characteristics. What is necessary is just to be able to form the hydrocarbon resin which it has, for example, it can be in the range of 4 to 8, but it is especially preferable to be in the range of 4 to 6.
When the monomer having a structure in which two or more cyclic structures are bonded is indene, the aliphatic carbon-carbon unsaturated bond is included as a part of the indene five-membered ring as described above, and The cyclic structure containing a group carbon-carbon unsaturated bond as a part thereof has 5 carbon atoms.

When the aliphatic carbon-carbon unsaturated bond is bonded to a cyclic structure, the aliphatic carbon-carbon unsaturated bond is bonded to the cyclic structure like a vinyl group contained in 1-vinylnaphthalene. May be bonded directly to each other, or may be bonded to the above cyclic structure via a spacer, such as an allyl group contained in allylnaphthalene.
Examples of the spacer include a hydrocarbon group bonded to a vinyl group such as a 2-propenyl group (allyl group) and 1-butenyl group, a carbonyl group bonded to a vinyl group such as an acryloyl group and a methacryloyl group. it can.
The number of carbon atoms of the spacer is not particularly limited as long as it can form a hydrocarbon resin having desired characteristics, and can be within a range of 1 to 3, for example.

The number of the aliphatic carbon-carbon unsaturated bond contained in the monomer having a structure in which two or more cyclic structures are bonded is usually one or more, for example, in the range of 1 to 2. Although it is possible, one is preferred.
In addition, the number of the above-mentioned aliphatic carbon-carbon unsaturated bonds is about each monomer when two or more types of monomers are included as a monomer having a structure in which two or more cyclic structures are bonded. It refers to the number of aliphatic carbon-carbon unsaturated bonds included.

  In addition, a structure in which two or more cyclic structures are bonded includes a structure in which a cyclic structure forms a condensed ring group such as a naphthalene structure, a fluorene structure, an anthracene structure, a phenanthrene structure, a benzothiophene structure, an indene, or the like, a biphenyl structure , Such as a terphenyl structure that forms a group in which cyclic structures are directly connected by a single bond, or a structure in which the cyclic structures include both a condensed ring group and a group in which the cyclic structures are directly connected by a single bond be able to.

Examples of the structure in which two or more cyclic structures are bonded include only an aromatic ring include, for example, a naphthalene structure, a biphenyl structure, an anthracene structure, a phenanthrene structure, a benzothiophene structure, and the like. Examples of such a ring structure include a fluorene structure and an indene structure.
In the present invention, it is particularly preferable that the structure in which the two or more cyclic structures are bonded includes an aromatic ring and a non-aromatic ring structure. The hydrocarbon resin of the present invention is excellent in processability, rolling resistance and wetness because the structure in which the two or more cyclic structures are combined includes an aromatic ring and a non-aromatic ring structure as the cyclic structure. This is because an elastomer composition for tires having an excellent balance of grip performance can be provided.

  The cyclic structure includes oxygen, nitrogen, sulfur, such as a benzothiophene structure, in addition to a ring structure formed only by carbon, such as a naphthalene structure, a fluorene structure, a biphenyl structure, an anthracene structure, a phenanthrene structure, and the like. It may have a heterocyclic ring containing atoms other than carbon such as.

  Moreover, the said cyclic structure may have a substituent. Examples of substituents include halogen atoms (F, Cl, Br, I), hydroxyl groups, carboxyl groups, cyano groups, amino groups, nitro groups, sulfo groups, carbamoyl groups, sulfamoyl groups, ureido groups, alkyl groups, alkenyls. Group, alkynyl group, aliphatic acyl group, aliphatic acyloxy group, alkoxy group, alkoxycarbonyl group, alkoxycarbonylamino group, alkylthio group, alkylsulfonyl group, aliphatic amide group, aliphatic sulfonamido group, aliphatic substituted amino group As typical examples, an aliphatic substituted carbamoyl group, an aliphatic substituted sulfamoyl group, an aliphatic substituted ureido group, and the like can be given.

The number of the cyclic structures included in the structure in which the two or more cyclic structures are combined may be two or more, and may be within the range of 2 to 6, but within the range of 2-3. Is preferred.
Specific examples of the monomer having a structure in which two cyclic structures are bonded include 1-vinylnaphthalene, 4-vinylbiphenyl, and indene.
Specific examples of the monomer having a structure in which three cyclic structures are bonded include 2,7-divinylfluorene and 9-vinylanthracene.

  In the present invention, the monomer having a structure in which two or more cyclic structures are bonded is preferably a naphthalene compound, a fluorene compound, a biphenyl compound, an anthracene compound, a phenanthrene compound, an indene compound and a benzothiophene compound. However, an indene compound is preferable, and indene is particularly preferable. When the monomer having a structure in which two or more cyclic structures are bonded is the above-mentioned compound, the hydrocarbon resin of the present invention has excellent workability and excellent balance between rolling resistance and wet grip performance. This is because the tire elastomer composition can be provided.

  Examples of the naphthalene compound include those having a naphthalene structure and one or more aliphatic carbon-carbon unsaturated bonds in the molecular structure, such as 1-vinylnaphthalene, 2-vinylnaphthalene, allylnaphthalene, butenyl. Naphthalene etc. can be mentioned.

  Examples of the fluorene compound include those having a fluorene structure and one or more aliphatic carbon-carbon unsaturated bonds in the molecular structure, such as 2,7-divinylfluorene, 2-vinylfluorene, allylfluorene, Examples include butenyl fluorene.

  Examples of the biphenyl compound include those having a biphenyl structure and one or more aliphatic carbon-carbon unsaturated bonds in the molecular structure. For example, 4-vinylbiphenyl, 4-vinyl-p-terphenyl, etc. Can be mentioned.

  Examples of the anthracene compound include an anthracene structure and one having at least one aliphatic carbon-carbon unsaturated bond in the molecular structure thereof. For example, 9-vinylanthracene, 2-vinylanthracene, 9,10-divinyl Anthracene, allyl anthracene, butenyl anthracene, etc. can be mentioned.

  Examples of the phenanthrene compound include those having a phenanthrene structure and one or more aliphatic carbon-carbon unsaturated bonds in the molecular structure, such as 9-vinylphenanthrene and 3-vinylphenanthrene. .

  The indene compound may be any compound having an indene structure in its molecular structure. For example, indene, methylindene, ethylindene, propylindene, butylindene, t-butylindene, sec-butylindene, n-pentyl. Examples include alkyl-substituted indenes such as indene, 2-methyl-butylindene, 3-methyl-butylindene, n-hexylindene, 2-methyl-pentylindene, 3-methyl-pentylindene, 4-methyl-pentylindene, etc. Can do.

  Examples of the benzothiophene compound include those having a benzothiophene structure and one or more aliphatic carbon-carbon unsaturated bonds in the molecular structure. For example, 5-vinylbenzothiophene, 2-vinyldibenzothiophene, etc. Can be mentioned.

The monomer having a structure in which two or more cyclic structures are bonded may include only one type of monomer, or may include a mixture of two or more types of monomers. Good.
For example, the monomer having a structure in which two or more cyclic structures are bonded may be a mixture of 9-vinylanthracene which is an anthracene compound and 9-vinylphenanthrene which is a phenanthrene compound.

  The content of the monomer unit having a structure in which two or more cyclic structures are bonded to each other in the aromatic monomer unit may be 50% by mass or more, and is in the range of 55% by mass to 99.9% by mass. In particular, it is preferably in the range of 58% by mass to 99.85% by mass, and particularly preferably in the range of 60% by mass to 99.8% by mass. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.

(2) Aromatic monomer unit The aromatic monomer unit includes a monomer unit having a structure in which two or more cyclic structures are bonded, but has a structure in which two or more cyclic structures are bonded. In addition to the monomer unit, a monomer unit containing only one cyclic structure, that is, a monomer unit containing only one aromatic ring as the cyclic structure may be included.
Examples of the monomer constituting the monomer unit containing only one cyclic structure include styrene, α-methylstyrene, vinyltoluene and the like.

  As the content of the aromatic monomer unit in the hydrocarbon resin, the hydrocarbon resin can provide an elastomer composition for tires that is excellent in workability and has a good balance of rolling resistance and wet grip performance. What is necessary is just to be able to do, for example, it can be in the range of 0.1 mass%-50 mass%, it is preferable that it is in the range of 5 mass%-45 mass%, and especially 8 mass%-43 It is preferably in the range of mass%, and particularly preferably in the range of 10 mass% to 40 mass%. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.

2. Aliphatic monomer unit As the aliphatic monomer unit in the present invention, an elastomer composition for a tire which exhibits the above-mentioned predetermined characteristics, is excellent in workability, and has an excellent balance of rolling resistance and wet grip performance is provided. Any hydrocarbon resin that can form a hydrocarbon resin can be used.
Such an aliphatic monomer unit may be any unit that does not contain an aromatic ring, such as a 1,3-pentadiene monomer unit, an alicyclic monoolefin monomer having 4 to 6 carbon atoms. A unit, a C4-C8 acyclic monoolefin monomer unit, an alicyclic diolefin monomer unit, etc. can be included preferably.
For example, as an aliphatic monomer unit, 1,3-pentadiene monomer unit 10% by mass to 60% by mass, C 4-6 alicyclic monoolefin monomer unit 1% by mass to 30% by mass, It may contain 1 to 50 mass% of an acyclic monoolefin monomer unit having 4 to 8 carbon atoms and 0 to 10 mass% of an alicyclic diolefin monomer unit.

The hydrocarbon content of 1,3-pentadiene monomer units in the hydrocarbon resin can provide a tire elastomer composition having excellent workability and excellent balance of rolling resistance and wet grip performance. What is necessary is just what can obtain resin, For example, it can be in the range of 10 mass%-60 mass%, It is preferable that it is in the range of 15 mass%-55 mass%, Especially, 20 mass% It is preferable to be in the range of 50% by mass to 50% by mass, and it is particularly preferable to be in the range of 25% to 48% by mass. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.
The cis / trans isomer ratio in 1,3-pentadiene is not particularly limited and may be any ratio.

The alicyclic monoolefin having 4 to 6 carbon atoms is a hydrocarbon compound having 4 to 6 carbon atoms having one aliphatic carbon-carbon unsaturated bond and a non-aromatic ring structure in its molecular structure. is there. Specific examples of the alicyclic monoolefin having 4 to 6 carbon atoms include cyclobutene, cyclopentene, cyclohexene, methylcyclobutene, and methylcyclopentene.
As the content of the alicyclic monoolefin monomer unit having 4 to 6 carbon atoms in the hydrocarbon resin, an elastomer composition for a tire having excellent workability and excellent balance between rolling resistance and wet grip performance is used. What is necessary is just what can obtain the hydrocarbon resin which can be given, for example, it can be in the range of 1 mass%-30 mass%, and it is in the range of 3 mass%-28 mass%. In particular, it is preferably in the range of 5% by mass to 26% by mass, and particularly preferably in the range of 7% by mass to 25% by mass. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.
In addition, in a C4-C6 alicyclic monoolefin, the ratio of each compound applicable to this may be arbitrary ratios, Although it does not specifically limit, It is preferable that cyclopentene is contained at least, and C4-C6 The proportion of cyclopentene in the alicyclic monoolefin is more preferably 50% by mass or more.

An acyclic monoolefin having 4 to 8 carbon atoms is a chain hydrocarbon compound having one aliphatic carbon-carbon unsaturated bond in its molecular structure and 4 to 8 carbon atoms having no ring structure It is. Specific examples of the acyclic monoolefin having 4 to 8 carbon atoms include butenes such as 1-butene, 2-butene and isobutylene (2-methylpropene); 1-pentene, 2-pentene and 2-methyl-1 -Pentenes such as butene, 3-methyl-1-butene, 2-methyl-2-butene; hexenes such as 1-hexene, 2-hexene, 2-methyl-1-pentene; 1-heptene, 2-heptene Heptenes such as 2-methyl-1-hexene; 1-octene, 2-octene, 2-methyl-1-heptene, diisobutylene (2,4,4-trimethyl-1-pentene and 2,4,4- And octenes such as trimethyl-1-pentene).
As the content of the acyclic monoolefin monomer unit having 4 to 8 carbon atoms in the hydrocarbon resin, a tire elastomer composition having excellent workability and excellent balance of rolling resistance and wet grip performance is used. What is necessary is just what can obtain the hydrocarbon resin which can be given, for example, it can be in the range of 1 mass%-50 mass%, and it is in the range of 5 mass%-45 mass%. In particular, it is preferably within a range of 10% by mass to 42% by mass, and particularly preferably within a range of 15% by mass to 40% by mass. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.
In the acyclic monoolefin having 4 to 8 carbon atoms, the ratio of each of the corresponding compounds (including isomers) may be any ratio and is not particularly limited, but at least 2-methyl-2-butene, Preferably, at least one selected from the group consisting of isobutylene and diisobutylene is included, and the total amount of 2-methyl-2-butene, isobutylene and diisobutylene occupies in the alicyclic monoolefin having 4 to 6 carbon atoms. The ratio is more preferably 50% by mass or more.

The hydrocarbon resin may contain an alicyclic diolefin in its raw material.
An alicyclic diolefin is a hydrocarbon compound having two or more aliphatic carbon-carbon unsaturated bonds and a non-aromatic ring structure in its molecular structure. Specific examples of the alicyclic diolefin include multimers of cyclopentadiene such as cyclopentadiene and dicyclopentadiene, and multimers of methylcyclopentadiene and methylcyclopentadiene.
The content of the alicyclic diolefin monomer unit in the hydrocarbon resin is a hydrocarbon that can provide an elastomer composition for tires that is excellent in workability and has a good balance of rolling resistance and wet grip performance. What is necessary is just what can obtain resin, For example, it can be in the range of 0 mass%-10 mass%, It is preferable that it is in the range of 0 mass%-7 mass%, Especially 0 mass It is preferable to be in the range of 5% to 5% by weight, and it is particularly preferable to be in the range of 0% to 3% by weight. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.

The aliphatic monomer unit is a 1,3-pentadiene monomer unit, an alicyclic monoolefin monomer unit having 4 to 6 carbon atoms, or an acyclic monoolefin monomer unit having 4 to 8 carbon atoms. In addition to the alicyclic diolefin monomer unit, within a range where a hydrocarbon resin that gives an elastomer composition for a tire excellent in workability and excellent in balance of rolling resistance and wet grip performance can be obtained, Other monomer units may be included.
The other monomer used to constitute such other monomer unit may be a compound having addition polymerizability other than the above-described monomers and capable of addition copolymerization with 1,3-pentadiene or the like. There is no particular limitation. Examples of the other monomers include carbon numbers other than 1,3-pentadiene such as 1,3-butadiene, 1,2-butadiene, isoprene, 1,3-hexadiene, and 1,4-pentadiene. Unsaturated hydrocarbons such as cycloheptene, and other non-cyclic monoolefins having 4 to 8 carbon atoms such as ethylene, propylene, and nonene.
However, the content of the other monomer units in the hydrocarbon resin in the hydrocarbon resin is not particularly limited as long as the hydrocarbon resin having the predetermined characteristics can be obtained. Usually, it is in the range of 0% by mass to 30% by mass, preferably in the range of 0% by mass to 25% by mass, and more preferably in the range of 0% by mass to 20% by mass. This is because the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in processability and excellent in balance between rolling resistance and wet grip performance.

  As the content of the aliphatic monomer unit in the hydrocarbon resin, the hydrocarbon resin can provide an elastomer composition for tires that is excellent in workability and has a good balance of rolling resistance and wet grip performance. What is necessary is just to be able to do, for example, it can be in the range of 50 mass%-99.9 mass%, and it is preferable that it exists in the range of 60 mass%-90 mass%. When the content is within the above-described range, the hydrocarbon resin of the present invention can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance. It is.

3. Hydrocarbon Resin The number average molecular weight (Mn) of the hydrocarbon resin is not particularly limited as long as it is in the range of 400 to 3000, but is particularly preferably in the range of 450 to 2500. More preferably, it is in the range of 500-2000. This is because, when the number average molecular weight (Mn) is within the above range, the hydrocarbon resin can be excellent in compatibility with the elastomer. As a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the cross-linked product of the elastomer composition and can be excellent in rolling resistance.

The weight average molecular weight (Mw) of the hydrocarbon resin is not particularly limited as long as it is in the range of 700 to 6000, but is preferably in the range of 900 to 5000, particularly 1000 to 4000. It is more preferable to be within the range. This is because when the weight average molecular weight (Mw) is within the above range, the hydrocarbon resin can be excellent in compatibility with the elastomer. As a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the cross-linked product of the elastomer composition and can be excellent in rolling resistance.
In addition, when the weight average molecular weight (Mw) is within the above-described range, the hydrocarbon resin can easily increase the loss coefficient tan δ at 0 ° C. and can have excellent rolling resistance. Because.

  The Z-average molecular weight (Mz) of the hydrocarbon resin is not particularly limited as long as it is in the range of 1500 to 20000, but is particularly preferably in the range of 1800 to 15000, particularly 2000 to 10,000. It is more preferable to be within the range. This is because when the Z average molecular weight (Mz) is within the above-described range, the hydrocarbon resin can be excellent in compatibility with the elastomer. As a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the cross-linked product of the elastomer composition and can be excellent in rolling resistance.

In the present invention, the number average molecular weight (Mn), the weight average molecular weight (Mw), and the Z average molecular weight (Mz) of the hydrocarbon resin are determined as polystyrene converted values by high performance liquid chromatography.
More specifically, the number average molecular weight, the weight average molecular weight and the Z average molecular weight are measured by using “HLC-8320GPC” manufactured by Tosoh Corporation as a measuring device, and three “TSKgel SuperMultipore HZ” manufactured by Tosoh Corporation are connected. And measured with a tetrahydrofuran as a solvent at 40 ° C. and a flow rate of 1.0 mL / min.

  The ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight of the hydrocarbon resin is not particularly limited as long as it is within the range of 1.0 to 4.0, but 1.1 to It is preferably in the range of 3.5, more preferably in the range of 1.2 to 3.0. This is because when the ratio is within the above-described range, the hydrocarbon resin can be excellent in compatibility with the elastomer. Further, as a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the crosslinked product of the elastomer composition and can be excellent in wet grip performance.

  The ratio of the Z-average molecular weight to the weight-average molecular weight (Mz / Mw) of the hydrocarbon resin is not particularly limited as long as it is within the range of 1.0 to 4.0. It is preferably in the range of 3.5, more preferably in the range of 1.2 to 3.0. This is because when the ratio is within the above-described range, the hydrocarbon resin can be excellent in compatibility with the elastomer. Further, as a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the crosslinked product of the elastomer composition and can be excellent in wet grip performance.

The softening point of the hydrocarbon resin is not particularly limited as long as it is within the range of 80 ° C to 150 ° C, but is preferably within the range of 85 ° C to 145 ° C, particularly 90 ° C to More preferably, it is within the range of 140 ° C. This is because when the softening point is within the above-described range, the hydrocarbon resin can be excellent in compatibility with the elastomer. As a result, the hydrocarbon resin can easily reduce the loss coefficient tan δ at 60 ° C. of the cross-linked product of the elastomer composition and can be excellent in rolling resistance.
Further, since the softening point is within the above-described range, the hydrocarbon resin can easily increase the loss coefficient tan δ at 0 ° C. and can have excellent wet grip performance. .
In addition, the softening point in this invention is a value measured according to JISK6863 about a hydrocarbon resin, for example.

The hydrocarbon resin of the present invention can be used, for example, as a hydrocarbon resin used by mixing with an elastomer in an elastomer composition for various uses.
In the present invention, as described above, the hydrocarbon resin can provide an elastomer composition for tires that is excellent in workability and excellent in balance between rolling resistance and wet grip performance.
Therefore, the said hydrocarbon resin can be used suitably as a hydrocarbon resin used by mixing with an elastomer in the elastomer composition for tires, taking advantage of the characteristic, for example.

4). Process for Producing Hydrocarbon Resin The process for producing the hydrocarbon resin of the present invention may be any process that can obtain a hydrocarbon resin containing an aliphatic monomer unit and an aromatic monomer unit. A preferred method includes addition polymerization of a polymerizable component (monomer mixture A) having a monomer capable of constituting an aromatic monomer unit and an aromatic monomer unit.
For example, a hydrocarbon resin can be obtained by addition polymerization using a Friedel Crafts type cationic polymerization catalyst. The method suitably used for producing the hydrocarbon resin includes the following aluminum halide (A), halogenated hydrocarbon (B1) in which a halogen atom is bonded to a tertiary carbon atom, and a carbon-carbon bond. In combination with a halogenated hydrocarbon (B) selected from the group consisting of a halogenated hydrocarbon (B2) in which a halogen atom is bonded to a carbon atom adjacent to the saturated bond, a polymerization catalyst is obtained, and the above aliphatic monomer and The method which has the superposition | polymerization process of superposing | polymerizing the monomer mixture A containing an aromatic monomer can be mentioned.
Moreover, the addition amount of each monomer contained in the monomer mixture A can be the same as the content of each monomer unit in the hydrocarbon resin.
Therefore, as an aliphatic monomer unit, 1,3-pentadiene monomer unit 10% by mass to 60% by mass, C4-6 alicyclic monoolefin monomer unit 1% by mass to 30% by mass, It contains 1 to 50% by mass of acyclic monoolefin monomer units having 4 to 8 carbon atoms and 0 to 10% by mass of alicyclic diolefin monomer units. More specifically, in the case of producing a hydrocarbon resin containing 1% by mass to 50% by mass, the above production method is more preferably 10% to 60% by mass of 1,3-pentadiene monomer and 4 to 6 carbon atoms. 1% to 30% by weight of alicyclic monoolefin monomer, 1% to 50% by weight of acyclic monoolefin monomer having 4 to 8 carbon atoms, 0% by weight of alicyclic diolefin monomer unit -10% by mass, and inclusion of a monomer having a structure in which two or more cyclic structures are bonded There can be assumed to have a polymerization step of polymerizing the monomer mixture A comprising an aromatic monomer 0.1 wt% to 50 wt% of the above is at least 50 wt% in aromatic monomer mer.

Specific examples of the aluminum halide (A) include aluminum chloride (AlCl ₃ ) and aluminum bromide (AlBr ₃ ). Of these, aluminum chloride is preferably used from the viewpoint of versatility.
The amount of the aluminum halide (A) used is not particularly limited, but is preferably in the range of 0.05 to 10 parts by mass, more preferably 100 parts by mass of the polymerizable component (monomer mixture A). It is in the range of 0.1 to 5 parts by mass.

By using the halogenated hydrocarbon (B) in combination with the aluminum halide (A), the activity of the polymerization catalyst becomes extremely good.
Specific examples of the halogenated hydrocarbon (B1) in which a halogen atom is bonded to a tertiary carbon atom include t-butyl chloride, t-butyl bromide, 2-chloro-2-methylbutane, and triphenylmethyl chloride. . Among these, t-butyl chloride is particularly preferably used in that it has an excellent balance between activity and ease of handling.
Examples of the unsaturated bond in the halogenated hydrocarbon (B2) in which a halogen atom is bonded to a carbon atom adjacent to the carbon-carbon unsaturated bond include a carbon-carbon double bond and a carbon-carbon triple bond, and an aromatic ring. It also includes a carbon-carbon conjugated double bond in the above. Specific examples of such compounds include benzyl chloride, benzyl bromide, (1-chloroethyl) benzene, allyl chloride, 3-chloro-1-propyne, 3-chloro-1-butene, 3-chloro-1-butyne, Examples include cinnamon chloride. Among these, benzyl chloride is preferably used because it is excellent in balance between activity and ease of handling. In addition, halogenated hydrocarbon (B) may be used by 1 type, or may be used in combination of 2 or more types.
The use amount of the halogenated hydrocarbon (B) is preferably in the range of 0.05 to 50, more preferably in the range of 0.1 to 10, as a molar ratio to the aluminum halide (A).

  In performing the polymerization reaction, the order of adding each component of the monomer mixture and the polymerization catalyst to the polymerization reactor is not particularly limited, and may be added in any order, but the polymerization reaction is well controlled, From the viewpoint of more accurately controlling the weight average molecular weight and the like, after adding the monomer mixture and a part of the components of the polymerization catalyst to the polymerization reactor and starting the polymerization reaction, the remainder of the polymerization catalyst is polymerized It is preferable to add to the vessel.

  In the production of the hydrocarbon resin, when the alicyclic monoolefin monomer unit is included as the aliphatic monomer unit, first, the aluminum halide (A) and the alicyclic monoolefin may be mixed. preferable. This is because by subjecting the aluminum halide (A) and the alicyclic monoolefin to contact treatment, gel formation can be prevented and a hydrocarbon resin in which the weight average molecular weight and the like are controlled with high accuracy can be obtained.

  The amount of the alicyclic monoolefin mixed with the aluminum halide (A) is preferably at least 5 times (mass ratio) the amount of the aluminum halide (A). If the amount of the alicyclic monoolefin is too small, the effect of preventing gel formation may be insufficient. The mass ratio of the alicyclic monoolefin to the aluminum halide (A) is preferably 5: 1 to 120: 1, more preferably 10: 1 to 100: 1, and even more preferably 15: 1 to 80: 1. . If the alicyclic monoolefin is used in an excessive amount from this ratio, the catalytic activity is lowered and the polymerization may not proceed sufficiently.

  When mixing the aluminum halide (A) and the alicyclic monoolefin, the charging order is not particularly limited, and the aluminum halide (A) may be charged into the alicyclic monoolefin, and conversely, An alicyclic monoolefin may be introduced into the aluminum halide (A). Since mixing usually involves exotherm, an appropriate diluent can also be used. As the diluent, a solvent described later can be used.

When the aliphatic monomer unit includes a 1,3-pentadiene monomer unit, an acyclic monoolefin monomer unit, etc. in addition to the alicyclic monoolefin monomer unit, as described above. After preparing the mixture M of the aluminum halide (A) and the alicyclic monoolefin, it is preferable to mix the mixture M with the mixture a containing at least 1,3-pentadiene and the acyclic monoolefin. The mixture a may contain an alicyclic diolefin.
The preparation method of the mixture a is not particularly limited, and each of the pure compounds may be mixed to obtain the target mixture a. For example, a mixture containing the target monomer derived from a fraction of a naphtha decomposition product May be used to obtain the desired mixture a. For example, in order to blend 1,3-pentadiene or the like into the mixture a, a C5 fraction after extracting isoprene and cyclopentadiene (including its multimer) can be suitably used.
It is preferable to further mix the halogenated hydrocarbon (B) together with the mixture a and the mixture M. There are no particular restrictions on the order of these three parties.

  From the viewpoint of better controlling the polymerization reaction, it is preferable to carry out the polymerization reaction by adding a solvent to the polymerization reaction system. The type of the solvent is not particularly limited as long as it does not inhibit the polymerization reaction, but saturated aliphatic hydrocarbons or aromatic hydrocarbons are preferable. Examples of the saturated aliphatic hydrocarbon used as the solvent include n-pentane, n-hexane, 2-methylpentane, 3-methylpentane, n-heptane, 2-methylhexane, 3-methylhexane, and 3-ethylpentane. , 2,2-dimethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, 3,3-dimethylpentane, 2,2,3-trimethylbutane, 2,2,4-trimethylpentane, etc. 5-10 chain saturated aliphatic hydrocarbons; cyclic saturated aliphatic hydrocarbons having 5 to 10 carbon atoms such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane. Examples of the aromatic hydrocarbon used as the solvent include aromatic hydrocarbons having 6 to 10 carbon atoms such as benzene, toluene and xylene. A solvent may be used individually by 1 type and may be used as a 2 or more types of mixed solvent. Although the usage-amount of a solvent is not specifically limited, It is preferable that it exists in the range of 10 mass parts-1,000 mass parts with respect to 100 mass parts of polymeric components (monomer mixture A), and 50 mass parts- More preferably, it is in the range of 500 parts by weight. For example, a mixture of an addition polymerizable component and a non-addition polymerizable component such as a mixture of cyclopentane and cyclopentene derived from the C5 fraction is added to the polymerization reaction system, and the addition polymerizable component is a single amount. It can be used as a component of the body mixture, and the non-addition polymerizable component can be used as a solvent.

  The polymerization temperature for carrying out the polymerization reaction is not particularly limited, but is preferably in the range of −20 ° C. to 100 ° C., and preferably in the range of 0 ° C. to 75 ° C. If the polymerization temperature is too low, the polymerization activity may be reduced and productivity may be inferior. If the polymerization temperature is too high, the controllability such as the weight average molecular weight of the resulting hydrocarbon resin may be inferior. The pressure for performing the polymerization reaction may be atmospheric pressure or increased pressure. The polymerization reaction time can be appropriately selected, but is usually selected in the range of 10 minutes to 12 hours, preferably 30 minutes to 6 hours.

  The polymerization reaction can be stopped by adding a polymerization terminator such as methanol, an aqueous sodium hydroxide solution, or an aqueous ammonia solution to the polymerization reaction system when a desired polymerization conversion rate is obtained.

The method for producing the hydrocarbon resin includes at least the polymerization step, but may include other steps as necessary.
Examples of the other steps include, for example, a catalyst residue that is generated when a polymerization terminator is added in the polymerization step after the polymerization step to inactivate the polymerization catalyst, and the catalyst residue insoluble in the solvent is removed by filtration or the like. After the polymerization reaction is stopped by the removal step and the polymerization step, the unreacted monomer and solvent are removed, and the low molecular weight oligomer component is removed by steam distillation or the like, followed by cooling to obtain a solid unmodified resin. It can have a recovery process.

B. Next, the tire elastomer composition of the present invention will be described.
The tire elastomer composition of the present invention includes at least one elastomer, at least one filler, and the above-described hydrocarbon resin.

  According to the present invention, by using the above-described hydrocarbon resin, it is possible to manufacture a tire having excellent workability and excellent balance between rolling resistance and wet grip performance.

The tire elastomer composition of the present invention has an elastomer, a filler, and a hydrocarbon resin.
Hereafter, each component of the elastomer composition for tires of this invention is demonstrated in detail.

1. Hydrocarbon Resin The content of the hydrocarbon resin is not particularly limited as long as it can provide an elastomer composition for tires that is excellent in workability and has a good balance between rolling resistance and wet grip performance.
The content is, for example, a ratio with respect to 100 parts by mass of the elastomer, and can be within a range of 0.1 parts by mass to 50 parts by mass, and particularly preferably within a range of 1 part by mass to 30 parts by mass. In particular, it is preferably in the range of 1.5 to 20 parts by mass. This is because when the content is within the above-described range, the tire elastomer composition has excellent workability and excellent balance between rolling resistance and wet grip performance.

  The hydrocarbon resin can be the same as that described in the section “A. Hydrocarbon resin”, and the description thereof is omitted here.

2. Elastomer As the elastomer, known elastomers used for tire elastomer compositions can be used.
Examples of such an elastomer include natural rubber, polyisoprene rubber, emulsion polymerization styrene-butadiene copolymer rubber, solution polymerization styrene-butadiene copolymer rubber, and polybutadiene rubber (high cis-BR and low cis BR may be used. Also, it may be a polybutadiene rubber containing crystal fibers made of 1,2-polybutadiene polymer), styrene-isoprene copolymer rubber, butadiene-isoprene copolymer rubber, styrene-isoprene-butadiene copolymer rubber, acrylonitrile- Examples thereof include butadiene copolymer rubber and acrylonitrile-styrene-butadiene copolymer rubber.
In addition, the said elastomer should just contain at least 1 type, may contain only 1 type, and may mix and use 2 or more types.

3. Filler As said filler, what is generally used for the elastomer composition for tires can be used, for example, carbon black, clay, diatomaceous earth, silica, talc, barium sulfate, calcium carbonate, magnesium carbonate, metal oxide. , Mica, graphite, aluminum hydroxide, various metal powders, wood powder, glass powder, ceramic powder, etc., inorganic hollow fillers such as glass balloons, silica balloons, polystyrene, polyvinylidene fluoride, polyvinylidene fluoride copolymers, etc. The organic hollow filler which consists of etc. can be mentioned.
Among these fillers, for example, silica, carbon black and the like described in JP-A-2016-30795 can be used.
In the present invention, the filler is preferably silica. This is because when the filler is silica, the tire elastomer composition has excellent wet grip properties.
Moreover, the filler should just contain at least 1 type, may contain only 1 type, and may mix and use 2 or more types.

As content of the said filler, what is excellent in workability and can obtain the elastomer composition for tires which was excellent in the balance of rolling resistance and wet grip performance should just be obtained.
The content is, for example, a ratio with respect to 100 parts by mass of the elastomer and can be within a range of 30 parts by mass to 250 parts by mass, and particularly preferably within a range of 30 parts by mass to 200 parts by mass. , Preferably in the range of 40 parts by weight to 150 parts by weight, and particularly preferably in the range of 50 parts by weight to 130 parts by weight. This is because when the content is within the above-described range, the tire elastomer composition has excellent processability and wet grip properties.

4). Tire Elastomer Composition The tire elastomer composition of the present invention has an elastomer, a filler, and a hydrocarbon resin, but may contain other components as necessary.
Examples of the other components include compounding agents such as a silane coupling agent, a crosslinking agent, a crosslinking accelerator, a crosslinking activator, an anti-aging agent, an activator, a process oil, a plasticizer, a lubricant, and a tackifier. Necessary amount can be blended.
Such other components and their contents can be the same as those described in, for example, JP-A-2006-30795.

  The manufacturing method of the tire elastomer composition of the present invention may be obtained by kneading each component according to a conventional method, for example, after kneading the component and the elastomer excluding a thermally unstable component such as a crosslinking agent and a crosslinking accelerator, The kneaded product can be mixed with a thermally unstable component such as a crosslinking agent or a crosslinking accelerator to obtain a desired composition. The kneading temperature of the component excluding the thermally unstable component and the elastomer is preferably in the range of 80 ° C to 200 ° C, more preferably in the range of 120 ° C to 180 ° C, and the kneading time is preferably 30 ° C. Seconds to 30 minutes. The kneaded product and the thermally unstable component are usually mixed after cooling to 100 ° C. or lower, preferably 80 ° C. or lower.

  As a crosslinking method using the tire elastomer composition of the present invention as the tire elastomer crosslinked product, a known crosslinking method can be used. For example, a molding machine corresponding to a desired shape, for example, an extruder or an injection molding machine. Examples of the method include forming by a compressor, a roll, and the like, performing a crosslinking reaction by heating, and fixing the shape as a crosslinked product. In this case, it is possible to perform crosslinking after molding in advance or at the same time as molding. The molding temperature is usually in the range of 10 ° C to 200 ° C, preferably in the range of 25 ° C to 120 ° C. The crosslinking temperature is usually in the range of 100 ° C. to 200 ° C., preferably in the range of 130 ° C. to 190 ° C., and the crosslinking time is usually in the range of 1 minute to 24 hours, preferably 2 minutes to 12 hours. In the range of 3 minutes to 6 hours.

  In addition, depending on the shape and size of the elastomer crosslinked product for tires, even if the surface is crosslinked, the interior may not be sufficiently crosslinked. May be.

  As a heating method, a general method used for crosslinking of the elastomer composition such as press heating, steam heating, oven heating, hot air heating, or the like may be appropriately selected.

  Since the tire elastomer composition of the present invention can provide a tire having a good balance between rolling resistance and wet grip performance, it is excellent in low heat buildup and wet grip properties. The elastomer composition of the present invention is preferably used as a material for each part of a tire, such as a cap tread, a base tread, a carcass, a sidewall, and a bead part of the tire, taking advantage of such characteristics. In various tires such as all-season tires, high-performance tires, and studless tires, it can be suitably used for tire parts such as treads, carcass, sidewalls, and bead parts. It can be particularly suitably used as a tread for a fuel-efficient tire.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. In addition, the part and% in each example are a mass reference | standard unless there is particular notice.

  Various measurements were performed according to the following methods.

[Number average molecular weight, weight average molecular weight, Z average molecular weight and molecular weight distribution]
The hydrocarbon resin used as a sample is subjected to gel permeation chromatography analysis to determine the number average molecular weight (Mn), weight average molecular weight (Mw) and Z average molecular weight (Mz) in terms of standard polystyrene, and the molecular weight distribution is Mw / Mn ratio and Mz / Mw ratio. In addition, gel permeation chromatography analysis uses "HLC-8320GPC" manufactured by Tosoh Corporation as a measuring device, and a column using three connected "TSKgel SuperMultipore HZ" manufactured by Tosoh Corporation, with tetrahydrofuran as a solvent. , 40 ° C. and a flow rate of 1.0 mL / min.

[Softening point (℃)]
The hydrocarbon resin as a sample was measured according to JIS K 6863.

[Mooney viscosity (ML1 + 4)]
About the elastomer composition used as a sample, it measured on condition of the following according to JISK6300-1: 2001.
Test temperature: 100 ° C
・ Type of rotor: L type ・ Testing machine: Shimadzu Mooney Viscometer SMV-300J manufactured by Shimadzu Corporation

[Tensile strength (MPa) and elongation (%)]
About the test piece of the elastomer crosslinked material used as a sample, tensile strength (tensile stress (MPa)) and elongation (elongation (%)) were measured in accordance with JIS K 6251: 2010 under the following conditions.
-Test piece preparation method: After sheet preparation by press vulcanization, punching process-Test piece shape: Dumbbell shape No. 3-Specimen sampling direction: Parallel to line arrangement-Number of test pieces: 3
・ Measurement temperature: 23 ℃
・ Test speed: 500 mm / min
・ Testing machine: TENSOMETER 10k manufactured by ALPHA TECHNOLOGIES
・ Test machine capacity: Load cell type 1kN

[Loss tangent tan δ]
The loss tangent tan δ at 0 ° C. and 60 ° C. was measured under the following measurement conditions for the test piece of the crosslinked elastomer product as a sample under the following measurement conditions under the conditions of dynamic strain 0.5% and 10 Hz. . About this characteristic, it showed with the index | exponent which makes a reference | standard sample (after-mentioned comparative example 1) 100.
The higher the loss tangent tan δ at 0 ° C., the better the wet grip performance, and the lower the loss tangent tan δ at 60 ° C., the better the rolling resistance.
Measurement item: Dynamic storage elastic modulus E '
: Dynamic loss modulus E ''
: Loss tangent tan δ
-Sample preparation method: punching from sheet-Specimen shape: length 50 mm x width 2 mm x thickness 2 mm
・ Number of specimens: 1
・ Distance between clamps: 20mm

[Example 1]
A polymerization reactor was charged with a mixture of 56.1 parts of cyclopentane and 15.5 parts of cyclopentene. The temperature was raised to 70 ° C., and then 0.75 part of aluminum chloride was added (mixture M ₁ ).
Subsequently, 16.7 parts of 1,3-pentadiene, 18.4 parts of isobutylene, 0.1 part of diisobutylene, 0.1 part of dicyclopentadiene, 0.2 part of C4-C6 unsaturated hydrocarbon, C4-C6 saturated carbonization Mixture a ₁ consisting of 7.2 parts of hydrogen and 19.0 parts of aromatic monoolefin is continuously added to the polymerization reactor containing said mixture M ₁ while maintaining the temperature (70 ° C.) for 60 minutes. Polymerization was carried out. Thereafter, an aqueous sodium hydroxide solution was added to the polymerization reactor to stop the polymerization reaction. Table 1 summarizes the types and amounts of the components in the polymerization reactor during the polymerization reaction. After removing the precipitate generated by the termination of polymerization by filtration, the obtained polymer solution was charged into a distillation kettle and heated in a nitrogen atmosphere to remove the polymerization solvent and unreacted monomers. Next, the oligomer component having a low molecular weight was distilled off at 240 ° C. or higher while blowing saturated water vapor.
As the aromatic monoolefins contained in the mixture _{a 1,} 0.95 parts of styrene (aromatic in Zokutan mer 5.0 wt%) and 1-vinylnaphthalene 18.05 parts (in aromatic monomer mer 95 0.0 mass%) was used.

[Examples 2-3 and Comparative Examples 1-3]
A hydrocarbon resin was obtained in the same manner as in Example 1 except that the types and amounts of the components added to the polymerization reactor were changed as shown in Table 1 below.
In Examples 2-3 and Comparative Examples 2-3, styrene is used as an aromatic monomer other than the monomer having a structure in which two or more cyclic structures are bonded, as in Example 1. is there.
Moreover, in the comparative example 1, an aromatic monomer is not included.

[Production and Evaluation of Elastomer Composition and Crosslinked Elastomer]
In a Banbury mixer, 100 parts of solution-polymerized styrene-butadiene rubber (S-SBR) is masticated for 30 seconds, and then 53.0 parts of silica (trade name “Zeosil 1115MP” manufactured by Rhodia), silane coupling agent: screw 7.0 parts of [3- (triethoxysilyl) propyl] tetrasulfide (Degussa, trade name “Si69”) and 10 parts of the hydrocarbon resin obtained in Example 1 were added, and after kneading for 90 seconds, silica was added. (Rhodia Co., Ltd., trade name “Zeosil 1115MP”) 37.0 parts, zinc oxide 3.0 parts, stearic acid 2.0 parts and anti-aging agent: N-phenyl-N ′-(1,3-dimethylbutyl)- Add 2.0 parts of p-phenylenediamine (trade name “NOCRACK 6C”, manufactured by Ouchi Shinsei Co., Ltd.), knead for 90 seconds, and then process oil (Shin Nippon) 30 parts of petroleum products, trade name “Aromax T-DAE” were introduced.
Thereafter, the mixture was kneaded at 90 ° C. as a starting temperature, kneaded at 145 ° C. to 155 ° C. for 60 seconds or more (primary kneading), and then the kneaded product was discharged from the mixer.

  The obtained kneaded product was cooled to room temperature and then kneaded again (secondary kneading) at 90 ° C. for 2 minutes in a Banbury mixer, and then the kneaded product was discharged from the mixer. The temperature of the kneaded product at the end of kneading was 145 ° C.

  Next, with two rolls at 50 ° C., the obtained kneaded product was mixed with 2.0 parts of sulfur and a vulcanization accelerator: N-cyclohexyl-2-benzothiazolylsulfenamide (CBS trade name “NOXELLA CZ-G”). 1.9 parts of Ouchi Shinsei Chemical Industry Co., Ltd.) and 1.9 parts of diphenylguanidine (DPG product name “Noxeller D”, Ouchi Shinsei Chemical Co., Ltd.) are added and kneaded (mixed with vulcanizing agent) After kneading, the sheet-like elastomer composition was taken out.

  This elastomer composition was press-crosslinked for 40 minutes at a press pressure of about 8 MPa and a press temperature of 160 ° C., and then aged overnight in a thermostatic chamber at 23 ° C., and then a test piece of 150 mm × 150 mm × 2 mm thick elastomer cross-linked product Was made.

About the obtained elastomer composition and elastomer crosslinked product produced using the hydrocarbon resin of Example 1, the Mooney viscosity of the elastomer composition, the tensile strength (MPa) of the elastomer crosslinked product, the elongation (%), and the loss tangent Tan δ was measured. The results are shown in Table 1.
For the obtained hydrocarbon resins of Examples 2 to 3 and Comparative Examples 1 to 3, respectively, an elastomer composition and a crosslinked elastomer were prepared in the same manner, and the Mooney viscosity of the elastomer composition and the tension of the crosslinked elastomer were obtained. Strength (MPa), elongation (%) and loss tangent tan δ were measured. The results are shown in Table 1.
The kneading conditions for primary kneading, secondary kneading and vulcanizing agent kneading were as shown below.

(Kneading conditions for primary and secondary kneading)
・ Testing machine: Laboratory Plast Mill, Banbury mixer B-600 manufactured by Toyo Seiki Seisakusho Co., Ltd.
-Filling ratio: 70-75 vol%
・ Rotor speed: 50rpm
・ Test start set temperature: 90 ℃

(Kneading conditions for vulcanizing agent)
・ Testing machine: Ikeda Machine Industries Co., Ltd. electric heating type high temperature roll machine ・ Roll size: 6φ × 16
-Front roll speed: 24rpm
-Front / rear roll rotation ratio: 1: 1.22
・ Roll temperature: 50 ℃ ± 5 ℃
・ Number of turn-over: Twice left and right ・ Rounding width: Roll interval approx. 0.8mm
・ Number of rounding: 5 times

From Table 1, it was confirmed that the loss tangent tan δ at 0 ° C. was high and the loss tangent tan δ at 60 ° C. was low in the examples. From this result, it was confirmed that both the rolling resistance and the wet grip performance were excellent.
That is, from Table 1, those excellent in both rolling resistance and wet grip performance include monomer units having a structure in which two or more cyclic structures are combined in a predetermined ratio, and have a predetermined number average molecular weight and weight. Average molecular weight, Z average molecular weight, ratio of weight average molecular weight to number average molecular weight, ratio of Z average molecular weight to weight average molecular weight, softening point temperature, etc., in particular, for example, weight average molecular weight (Mw) and weight average molecular weight It was confirmed that the ratio (Mw / Mn) to the number average molecular weight (Mn) was moderately low and the softening point temperature was moderately high.

Claims (5)

A hydrocarbon resin comprising an aliphatic monomer unit and an aromatic monomer unit,
A content of the monomer unit having a structure in which two or more cyclic structures are bonded in the aromatic monomer unit in the aromatic monomer unit is 50% by mass or more,
The number average molecular weight (Mn) is in the range of 400-3000,
The weight average molecular weight (Mw) is in the range of 700-6000,
Z average molecular weight (Mz) is in the range of 1500-20000,
The ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) is in the range of 1.0 to 4.0,
The ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw) is in the range of 1.0 to 4.0,
A hydrocarbon resin having a softening point temperature in the range of 80 ° C to 150 ° C. 1,3-pentadiene monomer unit 10 mass% to 60 mass%,
1 to 30% by mass of an alicyclic monoolefin monomer unit having 4 to 6 carbon atoms,
1 to 50 mass% of acyclic monoolefin monomer unit having 4 to 8 carbon atoms,
The hydrocarbon resin according to claim 1, comprising 0% by mass to 10% by mass of an alicyclic diolefin monomer unit and 0.1% by mass to 50% by mass of the aromatic monomer unit. .   The monomer having a structure in which two or more cyclic structures are bonded is at least one selected from the group consisting of naphthalene compounds, fluorene compounds, biphenyl compounds, anthracene compounds, phenanthrene compounds, indene compounds, and benzothiophene compounds. The hydrocarbon resin according to claim 1 or 2, wherein   A tire elastomer composition comprising at least one elastomer, at least one filler, and the hydrocarbon resin according to any one of claims 1 to 3.   The tire elastomer composition according to claim 4, wherein the filler is silica.