Adhesive composition for noise reduction tire as well as preparation method and application of adhesive composition

Abstract

The invention discloses an adhesive composition for a noise reduction tire as well as a preparation method and application of the adhesive composition. The adhesive composition for noise-reducing tires according to the present invention comprises a silanized polyolefin. The adhesive composition containing silanized polyolefin can connect a noise reduction foam strip and an inner liner on the inner side of a tire, so that the bonding flexibility and the bonding strength are enhanced.

Description

Technical Field

[0001] The invention belongs to the field of tires, and relates to an adhesive composition for noise reduction tires, a preparation method and an application thereof, and more specifically to an adhesive composition for bonding noise reduction foam strips on the inner surface of a tire, a preparation method and an application thereof. Background Art

[0002] When a car is running, the enclosed gas in the tire resonates in the air chamber and generates noise, which is called tire noise. The method to reduce tire noise is mainly to reduce the sound of gas vibration in the tire. The current technical means mainly focus on changing the composition of the inner surface of the tire, usually by setting noise reduction foam on the inner surface, such as adhering noise reduction foam strips on the inner surface.

[0003] The inner lining of a pneumatic tubeless tire is an airtight layer, which is usually a rubber layer containing halogenated butyl rubber. During the manufacturing process of a pneumatic tubeless tire, a release agent is usually applied to the surface of the airtight layer to facilitate separation from the vulcanization bladder. The presence of the release agent causes many adhesives to lose their bonding strength, resulting in the noise reduction foam strips being easily detached after adhesion. At the same time, the bonding layer between the noise reduction foam strips and the airtight layer must also withstand harsh driving conditions, such as high temperature and high humidity. Therefore, selecting a suitable adhesive to bond the noise reduction foam strips and the tire airtight layer is a difficult point in the manufacturing of noise reduction tires.

[0004] Patent document CN201580022802.5 discloses a method for preparing a noise-reducing foam strip tire. The adhesive layer used to bond the noise-reducing foam strip and the tire inner lining contains silanized polyether. The adhesive using moisture-curable silanized polyether has better bonding effect than silicone resin. However, the bonding strength of silanized polyether to the inner lining layer with halogenated butyl rubber as the main material is still insufficient. Summary of the invention

[0005] In order to improve the deficiencies of the prior art, the present invention provides an adhesive composition for noise reduction tires, a preparation method and an application thereof. The adhesive includes silanized polyolefin. The adhesive based on silanized polyolefin can firmly bond the noise reduction foam strip to the tire inner liner, and the bonding effect is better than that of the adhesive based on alkylated polyether.

[0006] An adhesive composition for a noise reduction tire, characterized in that the composition comprises silanized polyolefin.

[0007] According to an embodiment of the present invention, the silylated polyolefin is selected from at least one of silylated polyisobutylene copolymers, silylated amorphous α-olefin copolymers, silylated polypropylene, silylated ethylene-propylene polymers, and silylated polydiene, and the grafting rate of silane groups in the silylated polyolefin is 0.1 to 20 mol%.

[0008] According to an embodiment of the present invention, the adhesive composition further comprises an olefin polymer, and the olefin polymer comprises polyisobutylene and / or an amorphous α-olefin copolymer.

[0009] According to an embodiment of the present invention, the silylated polyolefin is selected from at least one of a polyolefin and a silane of the general formula RR'SiY2, wherein in the general formula RR'SiY2 of the silane, R is selected from a monovalent ethylenically unsaturated hydrocarbon or a hydrocarbyl group that can react with a free radical point generated on the main chain of the polyolefin; when R is selected from a hydrocarbyl group, it is not hydrolyzable;

[0010] R' is selected from an alkyl group, an aryl group or a Y group, and Y is selected from a hydrolyzable organic group.

[0011] According to an embodiment of the present invention, the number average molecular weight of the silylated polyolefin is 2,000-1,000,000.

[0012] According to an embodiment of the present invention, the adhesive composition further comprises an auxiliary agent, and the auxiliary agent is selected from at least one of a filler, a plasticizer, a pigment, a tackifier, a dehydrating agent, a catalyst, a thixotropic agent, an antioxidant, and a UV stabilizer.

[0013] A tire comprising an inner liner facing an inner cavity of the tire, an adhesive layer disposed on the inner liner and a noise reduction foam strip adhered to the inner liner of the tire through the adhesive layer, wherein the adhesive layer comprises the adhesive composition according to any one of claims 1 to 6.

[0014] According to an embodiment of the present invention, the foam of the noise reduction foam strip is polyurethane foam, polyethylene foam, PVC foam, preferably polyurethane foam.

[0015] According to an embodiment of the present invention, the polyurethane foam density is 10 to 35 kg / m 3 .

[0016] A method for providing a noise reduction foam strip on a tire comprises the following steps:

[0017] S1. The adhesive composition is applied to the surface of the liner and / or the radially outer surface of the foam strip;

[0018] S2. The foam strip is set close to the surface of the liner; and

[0019] The adhesive composition is crosslinked to form an adhesive layer.

[0020] Beneficial Effects

[0021] The adhesive composition of the present invention includes silylated polyolefin, which is moisture-curable, that is, in actual use, the silylated polyolefin undergoes cross-linking after the silane groups in the silylated polyolefin react with water, thereby increasing the adhesion of the sealant. Specifically, cross-linking occurs in the presence of ambient moisture, and the cross-linking produces two types of bonding: the first is the bonding between the polyurethane foam and the adhesive, and the open cells of the polyurethane foam strengthen this bonding; the second is the bonding between the adhesive and the liner, and the silylated olefin polymer and the tire inner liner layer mainly composed of halogenated butyl rubber have similar molecular main structures, and the bonding ability of the two is stronger. Therefore, the silylated polyolefin adhesive composition of the present invention can connect the noise reduction foam strip and the inner airtight layer of the tire, thereby enhancing the bonding flexibility and bonding strength. DETAILED DESCRIPTION

[0022] [Adhesive composition for noise reduction tire]

[0023] As mentioned above, the present invention provides an adhesive composition for a noise reduction tire, the composition comprising a silylated polyolefin.

[0024] According to an embodiment of the present invention, the adhesive composition is used to bond a noise reduction foam strip and a tire inner liner in a tire.

[0025] According to an embodiment of the present invention, the silylated polyolefin is at least one selected from silylated isobutylene polymer, silylated amorphous α-olefin polymer, silylated polypropylene, silylated ethylene-propylene polymer, and silylated polydiene.

[0026] According to an embodiment of the present invention, the silylated isobutylene polymer includes at least one of silylated polyisobutylene and silylated isobutylene copolymer. Exemplarily, the silylated isobutylene copolymer is selected from at least one of butyl rubber, isobutylene and (p-alkyl) styrene copolymer.

[0027] Preferably, in the copolymer of isobutylene and (p-alkyl)styrene, the molar content of (p-alkyl)styrene is less than or equal to 20 mol%, preferably the molar content of (p-alkyl)styrene is 0.1-20 mol%, for example, 0.5 mol%, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 15 mol%.

[0028] According to an embodiment of the present invention, the silylated polyolefin is a silylated polyisobutylene, a silylated isobutylene and p-toluene copolymer or a silylated amorphous α-olefin polymer.

[0029] According to an embodiment of the present invention, in the silylated amorphous α-olefin polymer, the amorphous α-olefin polymer refers to an amorphous homopolymer and / or copolymer of monomers such as ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3-ethyl-1-pentene, 1-octene, 1-decene, 1-undecene, etc. Exemplarily, the amorphous α-olefin polymer is selected from at least one of random polypropylene, propylene / ethylene amorphous copolymer, propylene / 1-butene amorphous copolymer, and ethylene / propylene / 1-butene terpolymer. Also exemplarily, the amorphous α-olefin polymer is selected as an ethylene / propylene / 1-butene terpolymer (APAO), preferably an APAO obtained by catalytic copolymerization of 10-15wt% ethylene, 55-60wt% propylene and 25-30wt% 1-butene mixed monomers, such as VESTOPLAST508 (Evonik).

[0030] According to an embodiment of the present invention, the grafting rate of silane groups in the silylated polyolefin is 0.1 to 20 mol%, preferably, the grafting rate of silane groups in the silylated polyolefin is 2 to 10 mol%, and the grafting rate is, for example, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, or 15 mol%.

[0031] According to an embodiment of the present invention, the grafting rate refers to the number of moles of silane groups per 100 moles of polyolefin molecules.

[0032] According to an embodiment of the present invention, the silylated polyolefin is moisture curable, that is, in actual use, specifically when used as an adhesive, the silane groups in the silylated polyolefin react with water to crosslink the silylated polyolefin, thereby increasing the adhesion of the sealant.

[0033] According to an embodiment of the present invention, the silylated polyolefin is selected from at least one of a polyolefin and a silane of the general formula RR'SiY2, wherein in the general formula RR'SiY2 of the silane, R is selected from a monovalent ethylenically unsaturated hydrocarbon or a hydrocarbyl group that can react with a free radical point generated on the main chain of the polyolefin; when R is selected from a hydrocarbyl group, it is not hydrolyzable;

[0034] R' is selected from an alkyl group, an aryl group or a Y group, and Y is selected from a hydrolyzable organic group;

[0035] R is selected from vinyl, allyl, butenyl, 4-pentenyl, 5-hexenyl, cyclohexenyl or cyclopentadienyl; for example, R is selected from vinyl.

[0036] According to an embodiment of the present invention, Y is selected from at least one or two or more of an alkoxy group, an acyloxy group, an oximo group, and a substituted amino group.

[0037] According to an embodiment of the present invention, the alkoxy group is selected from C1-C4 alkoxy groups, and preferably, the C1-C4 alkoxy group is selected from at least one or two or more of methoxy, ethoxy or butoxy groups.

[0038] According to an embodiment of the present invention, the acyloxy group is selected from formyloxy, acetoxy or propionyloxy.

[0039] According to an embodiment of the present invention, the oximo group is selected from -ON=C(CH3)2, -ON=C(CH3)(C2H5) and -ON=C(C6H5)2.

[0040] According to an embodiment of the present invention, the substituted amino group is selected from an alkylamino group or an arylamino group, for example, -NHCH3, -NHC2H5, or -NHC6H5.

[0041] According to an embodiment of the present invention, the R' is selected from methyl, ethyl, propyl, butyl, phenyl, alkylphenyl or Y. Further, the R' is selected from methyl or alkoxy.

[0042] According to a preferred embodiment of the present invention, the silane is, for example, at least one selected from vinyltriethoxysilane, vinyltrimethoxysilane or methylvinyldimethoxysilane.

[0043] According to an embodiment of the present invention, the number average molecular weight of the silylated polyolefin is 2000-1000000, preferably the number average molecular weight of the silylated polyolefin is 10000-500000, more preferably, the number average molecular weight of the silylated polyolefin is 10000-50000, for example, 10000, 100000, 200000, 300000, 400000, 500000, 600000, 700000, 800000, 900000.

[0044] According to an embodiment of the present invention, the adhesive composition further comprises an olefin polymer, wherein the olefin polymer comprises polyisobutylene and / or an amorphous α-olefin polymer. Studies have shown that the introduction of the olefin polymer can provide a certain initial viscosity for the adhesive composition, making it easier to apply glue.

[0045] According to an embodiment of the present invention, the amorphous α-olefin polymer refers to an amorphous homopolymer and / or copolymer of monomers such as ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3-ethyl-1-pentene, 1-octene, 1-decene, and 1-undecene.

[0046] According to an embodiment of the present invention, the amorphous α-olefin polymer includes at least one of random polypropylene, propylene / ethylene amorphous copolymer, propylene / 1-butene amorphous copolymer, and ethylene / propylene / 1-butene terpolymer.

[0047] Exemplarily, the amorphous α-olefin polymer is preferably an ethylene / propylene / 1-butene terpolymer (APAO), such as APAO obtained by catalytic copolymerization of 10-15 wt% ethylene, 55-60 wt% propylene and 25-30 wt% 1-butene mixed monomers, such as VESTOPLAST508 (Evonik).

[0048] According to an embodiment of the present invention, the adhesive composition further comprises an auxiliary agent, and the auxiliary agent is selected from at least one of a filler, a plasticizer, a pigment, an adhesion promoter, a dehydrating agent, a catalyst, a thixotropic agent, an antioxidant, and a UV stabilizer.

[0049] According to an embodiment of the present invention, the adhesive composition comprises, by mass, 100 parts of silylated polyolefin, 0 to 100 parts of olefin polymer, and optionally 0 to 100 parts of auxiliary agent, wherein the auxiliary agent has the above-mentioned definition.

[0050] According to an embodiment of the present invention, the adhesive composition includes 100 parts of silylated polyolefin and 10 to 90 parts of olefin polymer in parts by mass, and preferably the adhesive composition includes 20 to 80 parts of olefin polymer.

[0051] As an example, the adhesive composition includes 100 parts by mass of silylated isobutylene / p-methylstyrene copolymer and 80 parts by mass of polyisobutylene, and optionally includes or excludes 0-100 parts of an auxiliary agent, wherein the auxiliary agent has the above-mentioned definition.

[0052] According to an embodiment of the present invention, the silylated olefin polymer can be moisture-cured and cross-linked in the presence of ambient moisture, and the cross-linking produces two high-quality bonds: the first is the bond between the polyurethane foam and the adhesive, and the open cells of the polyurethane foam strengthen this bond; the second is the bond between the adhesive and the liner. The silylated olefin polymer and the tire inner liner with halogenated butyl rubber as the main body have similar molecular main structures, and the two have stronger bonding ability.

[0053] [Method for preparing adhesive composition for noise reduction tire]

[0054] As mentioned above, the present invention provides a method for preparing an adhesive composition for noise reduction tires, comprising the following steps: mixing, by weight, 100 parts of silylated polyolefin, 0 to 100 parts of olefin polymer, and optionally 0 to 100 parts of an auxiliary agent.

[0055] According to an embodiment of the present invention, the mixing is performed at a temperature of 100-200°C, preferably the mixing temperature is 120-180°C, for example, 140°C, 150°C, 160°C, 170°C.

[0056] According to an embodiment of the present invention, the mixing time is 0.1-4.0 h.

[0057] According to an embodiment of the present invention, the mixing is performed under stirring conditions.

[0058] [tire]

[0059] As described above, the present invention provides a tire comprising an inner liner facing the inner cavity of the tire, an adhesive layer disposed on the inner liner and a noise reduction foam strip adhered to the inner liner of the tire through the adhesive layer, wherein the adhesive layer comprises the adhesive composition described above.

[0060] According to an embodiment of the present invention, the foam of the noise reduction foam strip is selected from polyethylene foam, PVC foam, polyurethane foam, preferably polyurethane foam.

[0061] According to an embodiment of the present invention, the polyurethane foam density is 10 to 35 kg / m 3 The polyurethane foam density is preferably 10 to 20 kg / m 3 .

[0062] According to an embodiment of the present invention, the polyurethane foam can be basically manufactured by reacting a polyisocyanate compound with a polyhydroxy compound. In order to achieve the noise reduction effect without increasing the weight of the tire, the lower the density of the polyurethane foam material, the better.

[0063] According to an embodiment of the present invention, the foam strip is a circumferentially continuous strip.

[0064] [How to set noise reduction foam strips on tires]

[0065] As mentioned above, the present invention provides a method for setting a noise reduction foam strip on a tire, comprising the following steps:

[0066] S1. Applying a silanized polyolefin-based adhesive composition to the surface of the liner and / or the radially outer surface of the foam strip;

[0067] S2. The foam strip is set close to the surface of the liner; and

[0068] The adhesive composition is crosslinked to form an adhesive layer.

[0069] According to an embodiment of the present invention, the tire inner liner surface is optionally cleaned and dried before applying the adhesive composition, for example, by using a hot water high pressure water jet at about 65° C. and a pressure of less than 9.0 MPa.

[0070] The composition of the present invention and its preparation method and application will be described in further detail below in conjunction with specific examples. It should be understood that the following examples are only for exemplary description and explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies realized based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0071] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0072] Preparation Example 1

[0073] In the following examples and comparative examples, the preparation method of silylated isobutylene / p-methylstyrene copolymer is as follows:

[0074] A yellow polymer was prepared by the method of Example 1 in the patent document with reference application number CN00804495.3, namely a silylated isobutylene / p-methylstyrene copolymer. In the silylated isobutylene / p-methylstyrene copolymer, the molar content of trimethoxysilyl groups per mole of the silylated isobutylene / p-methylstyrene copolymer was 2.9 mol%, Mn=16100, and Mw / Mn=2.27.

[0075] Example 1

[0076] Adhesive composition:

[0077] 100 parts of silylated isobutylene / p-methylstyrene copolymer (Preparation Example 1)

[0078] 80 parts of polyisobutylene (BASF B10, Mn=15938, Mw=51000);

[0079] The components were added into a stainless steel container with mechanical stirring and stirred at 140°C for 1 h to obtain a uniformly mixed adhesive solution. The adhesive solution was coated on a tire strip with a width of 25 mm and a length of 200 mm. The coating surface was on the side of the tire strip containing the airtight layer. The thickness was 3 mm. A foam strip of similar size (Metzonor 023 sponge from Metzeler, Germany, with a density of 0.023 g / cm2) was covered on the adhesive layer. 3 ), cover and compact with a 5kg iron block, remove the weight after 4 hours, and let it stand naturally to obtain a test sample.

[0080] In the preparation of the composition, the mixing temperature is selected according to the softening point of the main components, as long as the glue can be obtained by mixing evenly. Those skilled in the art can select it according to the softening temperature and time of the components, and no specific limitation is made in the following examples.

[0081] Sample processing and testing:

[0082] Refer to GB / T 2790-1995 Adhesive 180° Peel Strength Test Method to determine peel strength:

[0083] 1) Aging of the test specimens at ambient temperature (23° C. and 50% relative humidity RH): The test specimens were placed at ambient temperature for 12 days and the peel strength was tested.

[0084] 2) Wet aging of test samples: The test samples were first placed at 23° C. and 50% RH for 6 days, and then at 70° C. and 100% RH for 6 days, and the peel strength was measured.

[0085] 3) The aged samples at ambient temperature and wet aged samples are subjected to fatigue tests and then tested for peel strength.

[0086] The fatigue test was conducted using a torsion fatigue tester. Test parameters: angle change from +6° to -6°; stress frequency: 20 Hz; - ambient temperature: 60°C; 100% relative humidity; number of cycles: 5×106 (approximately three days of testing).

[0087] The test results are shown in Table 1.

[0088] The following experiments were carried out in the same manner as in Example 1 except that the composition of the adhesive composition was different.

[0089] Example 2

[0090] Adhesive composition:

[0091] 100 parts of silylated isobutylene / p-methylstyrene copolymer (Preparation Example 1);

[0092] 80 parts of amorphous α-olefin copolymer (Evonik VESTOPLAST 508).

[0093] Example 3

[0094] Adhesive composition:

[0095] 100 parts of silylated amorphous α-olefin copolymer (VESTOPLAST 206 manufactured by Evonik).

[0096] 80 parts of amorphous α-olefin copolymer (Evonik VESTOPLAST 508).

[0097] Example 4

[0098] Adhesive composition:

[0099] 100 parts of silylated amorphous α-olefin copolymer (VESTOPLAST 206 manufactured by Evonik).

[0100] Polyisobutylene (BASF B10) 80 parts.

[0101] Example 5

[0102] The adhesive is a single component: 100 parts of silylated isobutylene / p-methylstyrene copolymer (Preparation Example 1).

[0103] Example 6

[0104] The adhesive is a single component: 100 parts of silanized amorphous α-olefin copolymer (Evonik VESTOPLAST 206).

[0105] Comparative Example 1

[0106] Adhesive components:

[0107] 100 parts of silanized polyether (S303H from Kaneka Chemical Co., Ltd.).

[0108] 80 parts of amorphous α-olefin copolymer (Evonik VESTOPLAST 508).

[0109] Comparative Example 2

[0110] One-component adhesive:

[0111] 100 parts of silanized polyether (S303H from Kaneka Chemical Co., Ltd.).

[0112] Table 1. Test results

[0113]

[0114] As shown in Table 1, the adhesive containing the moisture-curable silylated olefin polymer has a strong bonding ability to the noise reduction foam strip and the tire.

[0115] The above examples are used to illustrate the specific implementation of the present invention. However, the protection scope of the present invention is not limited to the above exemplary implementation. Any modification, equivalent substitution, improvement, etc. made by those skilled in the art within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. An adhesive composition for a noise reduction tire, characterized in that: The composition includes a silylated polyolefin.

2. The adhesive composition for noise reduction tire according to claim 1, characterized in that: The silylated polyolefin is selected from at least one of silylated polyisobutylene copolymers, silylated amorphous α-olefin copolymers, silylated polypropylene, silylated ethylene-propylene polymers, and silylated polydiene, and the grafting rate of silane groups in the silylated polyolefin is 0.1 to 20 mol%.

3. The adhesive composition for noise reduction tire according to claim 1 or 2, characterized in that: The adhesive composition further includes an olefin polymer including polyisobutylene and / or an amorphous α-olefin copolymer.

4. The adhesive composition for noise reduction tire according to any one of claims 1 to 3, characterized in that: The silylated polyolefin is selected from at least one of polyolefin and a silane of the general formula RR'SiY2, wherein R in the general formula RR'SiY2 of the silane is selected from a monovalent olefinic unsaturated hydrocarbon or a hydrocarbyl group that can react with a free radical point generated on the main chain of the polyolefin; when R is selected from a hydrocarbyl group, it is not hydrolyzable; R' is selected from an alkyl group, an aryl group or a Y group, and Y is selected from a hydrolyzable organic group.

5. The adhesive composition for noise reduction tire according to any one of claims 1 to 4, characterized in that: The number average molecular weight of the silylated polyolefin is 2,000-1,000,000.

6. The adhesive composition for noise reduction tire according to any one of claims 1 to 5, characterized in that: The adhesive composition further comprises an auxiliary agent, and the auxiliary agent is selected from at least one of a filler, a plasticizer, a pigment, a tackifier, a dehydrating agent, a catalyst, a thixotropic agent, an antioxidant, and an ultraviolet stabilizer.

7. A tire, characterized in that: The tire comprises an inner liner facing an inner cavity of the tire, an adhesive layer disposed on the inner liner, and a noise reduction foam strip adhered to the inner liner of the tire through the adhesive layer, wherein the adhesive layer comprises the adhesive composition according to any one of claims 1 to 6.

8. The tire according to claim 7, characterized in that: The foam of the noise reduction foam strip is polyurethane foam, polyethylene foam, PVC foam, preferably polyurethane foam.

9. The tire according to claim 8, characterized in that The polyurethane foam density is 10 to 35 kg / m 3 .

10. A method for providing a noise reducing foam strip on a tire, comprising the following steps: S1. Applying the adhesive composition according to any one of claims 1 to 6 to the surface of the liner and / or the radially outer surface of the foam strip; S2. The foam strip is set close to the surface of the liner; and The adhesive composition is crosslinked to form an adhesive layer.

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