JP7052285B2 - Thermoplastic Elastomer Compositions for Tire Inner Liners, Laminates, Tire Inner Liners and Pneumatic Tires - Google Patents

Description

The present invention relates to a thermoplastic elastomer composition for a tire inner liner, a laminate containing a film of the thermoplastic elastomer composition, a tire inner liner made of the laminate, and a pneumatic tire including the tire inner liner.

When a film made of a thermoplastic elastomer composition is used as a tire inner liner, a technique of laminating the film with a rubber layer has been proposed from the viewpoint of film protection or member handleability (Patent Documents 1 and Patent Documents). 2).
However, in the case of a sandwich structure in which both sides of the film are sandwiched between rubber layers, there is a problem that foaming is likely to occur in the film at the end of vulcanization due to volatile components such as water vapor generated during vulcanization.
On the other hand, in order to suppress such a vulcanization failure, a technique for adjusting the vulcanization temperature has also been proposed (Patent Document 3).

Japanese Unexamined Patent Publication No. 2012-6499 Japanese Unexamined Patent Publication No. 2013-129167 Japanese Unexamined Patent Publication No. 2009-214330

INDUSTRIAL APPLICABILITY The present invention can produce a tire inner liner that does not cause vulcanization failure such as film foaming during vulcanization even when the rubber layer is laminated and the film surface is covered with the rubber layer. An elastomer composition is provided.

The present inventor has made a thermoplastic elastomer composition for a tire inner liner in which rubber particles are dispersed in a thermoplastic resin in the range of 140 ° C. to 250 ° C. by differential scanning calorific value measurement (DSC measurement) of the thermoplastic elastomer composition. By setting the relationship between the peak area A of the crystal melting peak of the thermoplastic resin below 200 ° C. and the peak area B of 200 ° C. or higher as B / A ≧ 3.5, a composition with improved heat resistance can be obtained. We have found that film foaming during vulcanization can be suppressed, and completed the present invention.

The first invention of the present invention is a thermoplastic elastomer composition in which rubber particles are dispersed in a thermoplastic resin, and the crystal melting peak of the thermoplastic resin in the range of 140 to 250 ° C. by differential scanning calorimetry is less than 200 ° C. The peak area A and the peak area B at 200 ° C. or higher are given by the equation (1).
B / A ≧ 3.5 ・ ・ ・ (1)
A thermoplastic elastomer composition for a tire inner liner that satisfies the above conditions.
The second invention is a laminate for a tire inner liner, which comprises a film of the thermoplastic elastomer composition of the first invention and layers of a rubber composition laminated on both sides of the film.
The third invention is a tire inner liner made of the laminate of the second invention.
The fourth invention is a pneumatic tire including the tire inner liner of the third invention.

The present invention includes the following embodiments.
[1] A thermoplastic elastomer composition in which rubber particles are dispersed in a thermoplastic resin, and the peak area A of the crystal melting peak of the thermoplastic resin in the range of 140 to 250 ° C. by differential scanning calorimetry is less than 200 ° C. And the peak area B of 200 ° C or higher is given by the equation (1).
B / A ≧ 3.5 ・ ・ ・ (1)
A thermoplastic elastomer composition for tire inner liners that meets the requirements.
[2] The thermoplastic resin is nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon 69, nylon 610, nylon 612, nylon 6/66, nylon 6/66/12, nylon 6/66 /. The thermoplastic elastomer composition for a tire inner liner according to [1], which is at least one selected from the group consisting of 610, nylon MXD6, nylon 6T, nylon 6 / 6T, nylon 9T and ethylene vinyl alcohol copolymer.
[3] The rubber particles contain at least one selected from the group consisting of brominated isobutylene-p-methylstyrene copolymers and maleic anhydride-modified ethylene-α-olefin copolymers [1] or [2]. ] The thermoplastic elastomer composition for the tire inner liner according to.
[4] A laminate for a tire inner liner comprising a film of the thermoplastic elastomer composition according to any one of [1] to [3] and a layer of a rubber composition laminated on both sides of the film.
[5] The laminate according to [4], wherein the film has a thickness of 10 to 200 μm.
[6] A tire inner liner made of the laminate according to [4] or [5].
[7] A pneumatic tire including the tire inner liner according to [6].

The tire inner liner produced by using the thermoplastic elastomer composition of the present invention does not have film foaming during tire vulcanization.

The first invention relates to a thermoplastic elastomer composition for a tire inner liner. The thermoplastic elastomer composition of the first invention is used for producing a tire inner liner.
The thermoplastic elastomer composition of the first invention is a product in which rubber particles are dispersed in a thermoplastic resin. In other words, the thermoplastic elastomer composition of the first invention comprises a matrix made of a thermoplastic resin and a dispersed phase made of rubber particles. The thermoplastic elastomer composition of the first invention has a so-called sea-island structure, in which the thermoplastic resin forms the sea and the rubber particles form the islands.

The thermoplastic elastomer composition of the first invention has a peak area A of less than 200 ° C. and a peak of 200 ° C. or higher of the crystal melting peak of the thermoplastic resin in the range of 140 to 250 ° C. by differential scanning calorimetry (DSC measurement). Area B is equation (1)
B / A ≧ 3.5 ・ ・ ・ (1)
It is necessary to meet.
The ratio B / A of the peak area A of the crystal melting peak of the thermoplastic resin in the range of 140 to 250 ° C. below 200 ° C. and the peak area B of 200 ° C. or higher by differential scanning calorimetry (DSC measurement) is simply referred to as " Also called "area ratio B / A".
The B / A is preferably 3.5 to 15.0, more preferably 4.0 to 12.0. If the B / A is too small, the heat resistance of the thermoplastic elastomer composition will decrease, so there is a concern that foaming will occur during tire vulcanization. If the B / A is too large, the amount of highly rigid refractory resin will increase. Therefore, there is a concern that the fatigue durability of the thermoplastic elastomer composition may decrease.

The thermoplastic resin is not limited as long as it satisfies the above formula (1), but is preferably nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon 69, nylon 610, nylon 612, and the like. At least one selected from the group consisting of nylon 6/66, nylon 6/66/12, nylon 6/66/610, nylon MXD6, nylon 6T, nylon 6 / 6T, nylon 9T and ethylene vinyl alcohol copolymer. ..

Examples of the rubber constituting the rubber particles include a diene-based rubber, a hydrogenated product thereof and an epoxidized product, an olefin-based rubber, a halogen-containing rubber, a silicone rubber, a sulfur-containing rubber, and a fluororubber.
As the diene rubber and its hydrogenated material and epoxidized product, natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), styrene-butadiene-styrene block copolymer (SBS) ), Styrene-Isoprene-Styrene block copolymer (SIS), acrylic nitrile butadiene rubber (NBR), hydride NBR, hydride SBR, hydride SBS (SEBS), hydride SIS (SEPS), epoxidized natural rubber ( ENR), epoxidized styrene-butadiene rubber, epoxidized styrene-butadiene-styrene block copolymer (ESBS) and the like.
Examples of the olefin rubber include ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), maleic anhydride-modified ethylene-α-olefin copolymer, ethylene-glycidyl methacrylate copolymer, and maleic anhydride-modified ethylene-ethyl acrylate. Examples thereof include copolymers (modified EEA), butyl rubber (IIR), isobutylene and aromatic vinyl or diene monomer copolymers, acrylic rubber (ACM), styrene-isobutylene-styrene block copolymers (SIBS), ionomers and the like. ..
Examples of the halogen-containing rubber include halogenated butyl rubber such as brominated butyl rubber (Br-IIR) and chlorinated butyl rubber (Cl-IIR), and halogenated isomonoolefin-p-alkylstyrene copolymer (for example, brominated isobutylene-p-). Methylstyrene copolymer (BIMS)), halogenated isobutylene-isoprene copolymer rubber, chloroprene rubber (CR), hydrin rubber (CHR), chlorosulfonated polyethylene (CSM), chlorinated polyethylene (CM), maleic acid-modified chlorinated Examples thereof include polyethylene (M-CM).
Examples of the silicone rubber include methyl vinyl silicone rubber, dimethyl silicone rubber, and methyl phenyl vinyl silicone rubber. Examples of the sulfur-containing rubber include polysulfide rubber and the like. Examples of the fluorine rubber include vinylidene fluoride-based rubber, fluorine-containing vinyl ether-based rubber, tetrafluoroethylene-propylene-based rubber, fluorine-containing silicone-based rubber, and fluorine-containing phosphazen-based rubber.
Among them, brominated isobutylene-p-methylstyrene copolymer and maleic anhydride-modified ethylene-α-olefin copolymer are preferable from the viewpoint of air barrier property and the mixing property with the thermoplastic resin of the matrix.

The halogenated isomonoolefin-p-alkylstyrene copolymer can be produced by halogenating a copolymer of isomonoolefin and p-alkylstyrene, and can be produced by halogenating isomonoolefin and p-alkylstyrene. The mixing ratio, polymerization rate, average molecular weight, polymerization form (block copolymer, random copolymer, etc.), viscosity, halogen atom, etc. are not particularly limited, and depend on the physical properties required for the thermoplastic elastomer composition and the like. It can be selected arbitrarily. Examples of the isomonoolefin constituting the halogenated isomonoolefin-p-alkylstyrene copolymer include isobutylene, isopentene, and isohexene, but isobutylene is preferable. Examples of the p-alkyl styrene constituting the halogenated isomonoolefin-p-alkyl styrene copolymer include p-methyl styrene, p-ethyl styrene, p-propyl styrene, p-butyl styrene and the like, but p-butyl styrene is preferable. It is methylstyrene. Examples of the halogen constituting the halogenated isomonoolefin-p-alkylstyrene copolymer include fluorine, chlorine, bromine and iodine, but bromine is preferable. A particularly preferred halogenated isomonoolefin-p-alkylstyrene copolymer is a brominated isobutylene-p-methylstyrene copolymer.
The brominated isobutylene-p-methylstyrene copolymer has the formula (1).

It is a bromine of an isobutylene-p-methylstyrene copolymer having a repeating unit represented by the formula (2).

It has a repeating unit represented by. The brominated isobutylene-p-methylstyrene copolymer is available from ExxonMobil Chemical Company under the trade name EXXPRO®.

Examples of the maleic anhydride-modified ethylene-α-olefin copolymer include maleic anhydride-modified ethylene-butene copolymer, maleic anhydride-modified ethylene-propylene copolymer, maleic anhydride-modified ethylene-hexene copolymer, and maleylene anhydride. Examples thereof include acid-modified ethylene-octene copolymers and maleic anhydride-modified ethylene-4-methylpentene copolymers. The maleic anhydride-modified ethylene-butene copolymer can be obtained from, for example, Mitsui Chemicals, Inc. under the trade name of Toughmer (registered trademark) MH7010. The maleic anhydride-modified ethylene-propylene copolymer can be obtained from, for example, Mitsui Chemicals, Inc. under the trade name of Toughmer (registered trademark) MP6010. The maleic anhydride-modified ethylene-octene copolymer can be obtained from ExxonMobil Chemical Company under the trade name Exxelor® VA1840.

The rubber particles may contain various additives in addition to the rubber, if necessary. Examples of the additive include a vulcanization or cross-linking agent, a vulcanization or cross-linking accelerator, an antiaging agent, a reinforcing agent (filler) such as carbon black or silica, a plasticizer, and various oils.

The shape and size of the rubber particles are not limited as long as the effect of the present invention is obtained, but the shape of the rubber particles is preferably a sphere or an ellipsoid, and the volume sphere equivalent diameter of the rubber particles is preferably 0.1 to 10 μm. Yes, more preferably 0.1 to 5 μm, still more preferably 0.2 to 2 μm. If the diameter equivalent to the volume sphere is too small, the viscosity of the thermoplastic elastomer composition may increase and the workability may decrease, and if the diameter equivalent to the volume sphere is too large, the fatigue durability of the thermoplastic elastomer composition may decrease. There is.

The thermoplastic elastomer composition of the first invention can be produced by melt-kneading a thermoplastic resin, rubber, and various additives as needed. Preferably, the rubber is processed into pellets in advance with a rubber pelletizer, and the obtained rubber pellets, the thermoplastic resin, the cross-linking agent, and other additives as necessary are put into a twin-screw kneading extruder or the like. The rubber is dispersed in the thermoplastic resin by melt-kneading, and the rubber is dynamically crosslinked to produce a thermoplastic elastomer composition.

The second invention relates to a laminated body for a tire inner liner. The laminate of the second invention is used as a tire inner liner. The laminate of the second invention comprises a film of the thermoplastic elastomer composition of the first invention and a layer of a rubber composition laminated on both sides of the film.

The thickness of the film of the thermoplastic elastomer composition is not particularly limited, but is preferably 10 to 200 μm, more preferably 15 to 150 μm, and even more preferably 20 to 100 μm. If the thickness is too thin, the amount of air permeation increases and there is a concern that the desired barrier property cannot be secured. If the thickness is too thick, the rigidity of the film increases, and when used as a tire inner liner, from the inner surface of the tire. There is a concern that it will come off.

The film of the thermoplastic elastomer composition is not particularly limited, but can be produced by inflation molding, T-die extrusion molding, or the like.

As the rubber composition used for producing the laminate, the rubber composition used for the carcass layer, the belt layer and the like of the tire can be used. The rubber composition is a mixture of a rubber component and various additives as needed. The composition of the rubber composition is not limited as long as it does not interfere with the effects of the present invention.

Examples of the rubber component contained in the rubber composition include diene-based rubbers, hydrogenated products thereof and epoxidized products, olefin-based rubbers, halogen-containing rubbers, silicone rubbers, sulfur-containing rubbers, fluororubbers and the like.
As the diene rubber and its hydrogenated material and epoxidized product, natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), styrene-butadiene-styrene block copolymer (SBS) ), Styrene-Isoprene-Styrene block copolymer (SIS), acrylic nitrile butadiene rubber (NBR), hydride NBR, hydride SBR, hydride SBS (SEBS), hydride SIS (SEPS), epoxidized natural rubber ( ENR), epoxidized styrene-butadiene rubber, epoxidized styrene-butadiene-styrene block copolymer (ESBS) and the like.
Examples of the olefin rubber include ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), maleic anhydride-modified ethylene-α-olefin copolymer, ethylene-glycidyl methacrylate copolymer, and maleic anhydride-modified ethylene-ethyl acrylate. Examples thereof include copolymers (modified EEA), butyl rubber (IIR), isobutylene and aromatic vinyl or diene monomer copolymers, acrylic rubber (ACM), styrene-isobutylene-styrene block copolymers (SIBS), ionomers and the like. ..
Examples of the halogen-containing rubber include halogenated butyl rubber such as brominated butyl rubber (Br-IIR) and chlorinated butyl rubber (Cl-IIR), halogenated isobutylene-isoprene copolymer rubber, chloroprene rubber (CR), hydrin rubber (CHR), and chloro. Examples thereof include sulfonated polyethylene (CSM), chlorinated polyethylene (CM), maleic acid-modified chlorinated polyethylene (M-CM) and the like.
Examples of the silicone rubber include methyl vinyl silicone rubber, dimethyl silicone rubber, and methyl phenyl vinyl silicone rubber. Examples of the sulfur-containing rubber include polysulfide rubber and the like.
Examples of the fluorine rubber include vinylidene fluoride-based rubber, fluorine-containing vinyl ether-based rubber, tetrafluoroethylene-propylene-based rubber, fluorine-containing silicone-based rubber, and fluorine-containing phosphazen-based rubber.
Among them, diene rubber, olefin rubber, and halogen-containing rubber are preferable, and more preferably, natural rubber, epoxidized natural rubber, styrene butadiene rubber, and epoxidized styrene butadiene rubber are preferable from the viewpoint of co-crosslinkability with the adjacent rubber material. , Butadiene rubber, isoprene rubber, butyl rubber, halogenated butyl rubber, mixtures thereof, more preferably a combination of natural rubber and styrene butadiene rubber, a combination of natural rubber and butadiene rubber, a combination of natural rubber and butyl rubber, with natural rubber. For example, a combination of halogenated butyl rubber.

Additives to be added to the rubber composition include reinforcing agents (fillers) such as carbon black and silica, vulcanization or cross-linking agents, vulcanization or cross-linking accelerators, plasticizers, various oils, antiaging agents and the like. Can be done. The blending amount of the various additives can be a general blending amount conventionally used for tires as long as it does not contradict the object of the present invention.

The laminate of the second invention can be produced by laminating the rubber composition on the film of the thermoplastic elastomer composition of the first invention. More specifically, but not limited to, it can be manufactured as follows. First, the thermoplastic elastomer composition of the first invention is molded into a film by a molding device such as an inflation molding device or a T-die extruder to prepare a film of the thermoplastic elastomer composition. Next, by performing the step of laminating the rubber composition on both sides of the film while rolling it with a calendar or the like, the layers of the rubber composition are laminated on both sides of the film of the thermoplastic elastomer composition. Manufacture the laminated laminate. Alternatively, the rubber composition is rolled with a calendar or the like and formed into a sheet, and the obtained rubber composition sheet is used as a layer of the rubber composition, and if necessary, an adhesive is used to form a thermoplastic elastomer composition. The laminate may be manufactured by laminating on both sides of the film.

The thickness of the layer of the rubber composition is not particularly limited, but is preferably 0.1 to 2 mm, more preferably 0.1 to 1 mm, still more preferably 0.2 to 0.5 mm. be. If the thickness is too thin, there is a concern that the rubber composition layer on the surface may be damaged during molding or when the product is used. If the thickness is too thick, the rigidity of the rubber composition layer increases, and the thermoplastic elastomer composition There is a concern that it will come off from the surface of the film.

The third invention relates to a tire inner liner. The tire inner liner of the third invention is made of the laminate of the second invention.

The fourth invention relates to a pneumatic tire. The pneumatic tire of the fourth invention includes the tire inner liner of the third invention of the present invention.
Pneumatic tires can be manufactured by conventional methods. For example, the thermoplastic resin composition of the first invention is extruded into a film having a predetermined width and thickness, which is attached to a cylinder on a tire forming drum as an inner liner, and is composed of unvulcanized rubber on the cylinder. Members used in normal tire manufacturing such as carcass layer, belt layer, tread layer, etc. are sequentially laminated and extracted from the drum to make a green tire, and then this green tire is heated and vulcanized according to a conventional method to make a pneumatic tire. Can be manufactured.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples.

[raw materials]
The raw materials used in the following examples and comparative examples are as follows.

The following was used as the thermoplastic resin.
UBE Nylon (trademark) 5023B: Nylon 6/66 copolymer manufactured by UBE Kosan Co., Ltd. UBE Nylon (trademark) 1013B: Nylon 6 manufactured by Ube Kosan Co., Ltd.
UBE Nylon (Trademark) 1011FB: Nylon 6 manufactured by Ube Kosan Co., Ltd.
UBE Nylon (trademark) 7024B: Nylon 6/12 copolymer EVOH manufactured by Ube Kosan Co., Ltd .: "Soanol" (registered trademark) E3808 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.

The following rubber was used.
Brominated isobutylene-p-methylstyrene copolymer (Br-IPMS): "EXXPRO" (registered trademark) MDX89-4 manufactured by ExxonMobil Chemical Company.
Acid-modified ethylene-α-olefin copolymer: Maleic anhydride-modified ethylene-butene copolymer "Toughmer" (registered trademark) manufactured by Mitsui Chemicals Co., Ltd. MH7010

The following were used as cross-linking agents.
Zinc Oxide: Zinc Oxide No. 3 made by Shodo Chemical Industry Co., Ltd. Stearic acid: Beaded stearic acid made by NOF CORPORATION

The following were used as anti-aging agents.
6PPD: Flexsys N- (1,3-dimethylbutyl) -N'-phenyl-1,4-phenylenediamine "SANTOFLEX" (registered trademark) 6PPD

The following were used as processing aids.
Processing aid: Higher fatty acid ester "Stractol" (registered trademark) manufactured by S & S Japan Co., Ltd. WB222

[Preparation of thermoplastic elastomer composition]
Of the raw materials shown in Table 1, Br-IPMS was previously processed into pellets with a rubber pelletizer (manufactured by Moriyama Seisakusho Co., Ltd.). The obtained rubber pellets, thermoplastic resin, acid-modified ethylene-α-olefin copolymer, cross-linking agent and anti-aging agent are mixed in the blending ratio shown in Table 1 by a twin-screw kneading extruder (manufactured by Japan Steel Works, Ltd.). And kneaded at 250 ° C. for 3 minutes. The kneaded product was continuously extruded into a strand shape from an extruder, cooled with water, and then cut with a cutter to obtain pellet-shaped premixture a, premixture b, and premixture c.
Further, as an additional resin to the preliminary compound a, the amount of nylon 6 (“UBE Nylon” (trademark) 1013B manufactured by Ube Kosan Co., Ltd.) or nylon compound (“ZYTEL” manufactured by DuPont Co., Ltd. (registered trademark)) is shown in the amount shown in Table 2. ST811HS NC010) was added to prepare thermoplastic elastomer compositions a1 to a5. As an additional resin, nylon 6 (“UBE Nylon” (trademark) 1013B manufactured by Ube Kosan Co., Ltd.) as an additional resin was added to the premixed compound c to prepare a thermoplastic elastomer composition c. The premixed compound a to which no additional resin was added was designated as the thermoplastic elastomer composition a0. The premixed compound b was used as it was as the thermoplastic elastomer composition b without adding an additional resin.

[Film molding of thermoplastic elastomer composition]
The thermoplastic elastomer compositions a0 to a5, b and c are extruded at 240 ° C. using a T die sheet molding apparatus (manufactured by Tommy Kikai Kogyo Co., Ltd.), pulled onto a metal cooling roll, picked up by a pinch roll, and a film. A thermoplastic elastomer composition film was prepared by cutting off both ends and winding it with a winder. The thickness of each of the obtained films was 70 μm, and the film width was 350 mm.

[Calculation of area ratio B / A by differential scanning calorimetry]
The prepared thermoplastic elastomer composition film was measured twice using a differential scanning calorimeter (manufactured by METTLER TOLEDO) in a temperature range of -120 ° C to 250 ° C and a temperature rise rate of 10 ° C / min. bottom. The peak area A of the crystal melting peak of the thermoplastic resin from 140 ° C. to 250 ° C. below 200 ° C. and the peak area B of 200 ° C. or higher in the second measurement data (second run) are calculated by a computer and the area is calculated. The ratio B / A was calculated. The results are shown in Table 2.

[Preparation of rubber composition]
Of the raw materials shown in Table 3, each raw material excluding sulfur and the vulcanization accelerator was mixed for 5 minutes using a B-type Banbury mixer (1.8 L) manufactured by Kobe Steel, Ltd., and then sulfur and the vulcanization accelerator were added to this mixture. Was kneaded with an 8-inch test kneading roll machine for 4 minutes to obtain a rubber composition.

[Preparation of laminated body]
The molded film and the prepared rubber composition were laminated using a calendar to prepare a laminated body. The laminated body was a laminated body having a sandwich structure in which the upper and lower parts of the film were sandwiched between rubber compositions, the thickness of each rubber composition layer was 0.3 mm, and the total width of the laminated body was 420 mm.

[Manufacturing of pneumatic tires]
The produced laminated body was placed on a molded drum, and then tire members such as carcass were laminated by a conventional method to produce a green tire. This green tire was vulcanized by a normal vulcanization molding method to produce a 195 / 65R15 size pneumatic tire having each specification.

[Evaluation of inner liner vulcanization resistance in tire vulcanization]
The inner surface of the tire after vulcanization during the manufacture of the pneumatic tire was observed, and the presence or absence of inner liner foaming due to vulcanization was evaluated. The results are shown in Table 2.
In Comparative Examples 1 to 3 in which the area ratio B / A in DSC was lower than 3.5, remarkable foaming was observed in the inner liner, whereas in Examples 1 to 3 in which the area ratio B / A was 3.5 or more. It can be seen that in No. 4, there is no foaming and the product has good vulcanization resistance.

The thermoplastic elastomer composition of the present invention can be suitably used for producing a pneumatic tire.

Claims (7)

A thermoplastic elastomer composition in which rubber particles are dispersed in a thermoplastic resin, and has a peak area A of less than 200 ° C. and a peak area A of less than 200 ° C. of the crystal melting peak of the thermoplastic resin in the range of 140 to 250 ° C. by differential scanning calorimetry. The above peak area B is the equation (1).
3.5 ≤ B / A ≤ 15.0 ... (1)
The filling,
The thermoplastic resin comprises nylon 6 and nylon 6/66 copolymer.
The rubber particles contain a brominated isobutylene-p-methylstyrene copolymer and a maleic anhydride-modified ethylene-α-olefin copolymer .
A thermoplastic elastomer composition for a tire inner liner having a thermoplastic resin / rubber particle mixing amount ratio of 0.62 to 1.08. The thermoplastic elastomer composition for a tire inner liner according to claim 1, further comprising the thermoplastic resin, a nylon 6/12 copolymer and / or an ethylene vinyl alcohol copolymer. The thermoplastic elastomer composition for a tire inner liner according to claim 1 or 2, wherein 3.5 ≦ B / A ≦ 11.6. A laminate for a tire inner liner comprising a film of the thermoplastic elastomer composition according to any one of claims 1 to 3 and a layer of a rubber composition laminated on both sides of the film. The laminate according to claim 4, wherein the film has a thickness of 10 to 200 μm. A tire inner liner made of the laminate according to claim 4 or 5. A pneumatic tire comprising the tire inner liner according to claim 6.