Rubber composition and article thereof

Abstract

To provide an alternative compound having equal or better anti-oxidation, anti-ozonation, and migration properties through rubber.SOLUTION: The uncured composition comprises a partially saturated elastomer characterized in that no more than 15% of the total repeat unit of the partially saturated elastomer comprises double bonds, and 224 - trimethyl-l, 2-dihydroquinoline (TMDQ) or an oligomer thereof in place of some or all of a conventional antiozonant such as, for example, 6PPD.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a rubber composition and an article thereof. [Background technology]

[0002]

[0001] Rubber articles, such as vehicle tires, are degraded by atmospheric oxygen and ozone, resulting in discoloration and structural defects, such as cracks, under stress, such as during road use. Ozone can also react with some polymers in tires in ways that generate free radicals. Damage from ozone and free radicals can cause deterioration in appearance, as well as performance and safety issues. Therefore, antioxidants and antiozonants are incorporated into tire sidewalls to protect against the effects of atmospheric oxygen and ozone.

[0003] 6PPD is a compound that has antiozonant properties and is frequently incorporated into rubber articles, including vehicle tires.

[0004] [ka]

[0005] This compound migrates to the surface of vehicle tires over time, essentially forming a film that captures ozone before it can degrade the rubber. 6PPD is essentially self-replenished on the tire surface through continuous blooming. However, due to its high reactivity, 6PPD can be converted into 6PPD by-products. For example, 6PPD-quinone is an oxidation by-product of 6PPD in tires.

[0006] [ka]

[0007]

[0004] Therefore, replacement compounds having equivalent or better antioxidant, antiozonant, and migration through rubber properties are desirable. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent Application Publication No. 2023 / 0138073A1 [Patent Document 2] European Patent Application Publication No. 4261234A1 [Non-patent literature]

[0009] [Non-Patent Document 1] Standard Test Methods for Analysis and Testing of Petroleum and Related Products and British Standard 2000 Parts, 2003, 62nd edition [Non-patent document 2] The Vanderbilt Rubber Handbook, edited by Robert O. Babbit, (Norwalk, Connecticut, RTVanderbilt Company, Inc., 1978), pp. 344-346. Summary of the Invention [Means for solving the problem]

[0010] In accordance with the purposes of the disclosure as embodied and broadly described herein, the disclosure, in one embodiment, relates to an uncured composition comprising a partially saturated elastomer in which no more than 15% of the total repeating units of the partially saturated elastomer contain double bonds, and 2,2,4-trimethyl-1,2-dihydroquinoline (TMDQ) or an oligomer thereof. TMDQ or an oligomer thereof has antiozonant properties, thereby eliminating the need for conventional antiozonants, such as 6PPD. The use of TMDQ or an oligomer thereof provides good crack resistance properties. Also disclosed are vulcanized rubber compositions comprising the uncured composition after vulcanization, and articles comprising tires and / or tire components made from or including the vulcanized rubber compositions.

[0011]

[0006] Other systems, methods, features, and advantages of the present disclosure will be or become apparent to one of ordinary skill in the art upon examination of the following drawings and detailed description. All such additional systems, methods, features, and advantages are intended to be included within this specification, be within the scope of this disclosure, and be protected by the accompanying claims. In addition, all optional and preferred features and modifications of the described embodiments can be used in all embodiments of the present disclosure taught herein. Furthermore, the individual features of the dependent claims, and all optional and preferred features and modifications of the described embodiments, are combinable and interchangeable with each other.

[0012]

[0007] Further embodiments of the present disclosure will be readily understood by considering the following detailed description of various embodiments thereof in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0013] [Figure 1]

[0008] Figure 1 shows that in the prior art, the use of 6PPD and DTPD as antiozonants results in a rubber composition that is essentially free of cracks as determined by the ozone test method, where the rubber composition is comprised of a partially saturated elastomer containing repeat units, and greater than 15% of the total repeat units of the partially saturated elastomer contain double bonds. [Figure 2]

[0009] Figure 2 shows that the use of TMDQ as an antiozonant results in a rubber composition that is essentially free of cracks as determined by the ozone test method, wherein the rubber composition is comprised of a partially saturated elastomer containing repeat units, wherein not more than 15% of the total repeat units of the partially saturated elastomer contain double bonds. [Figure 3] 3A and 3B show that the use of TMDQ (3 phr and 5 phr, respectively) as an antiozonant results in a rubber composition having numerous small cracks as determined by the ozone test method, where the rubber composition is composed of a partially saturated elastomer containing repeat units, and more than 15% of the total repeat units of the partially saturated elastomer contain double bonds. DETAILED DESCRIPTION OF THE INVENTION

[0014]

[0011] Many modifications and other embodiments of the disclosed compositions and methods will come to mind to one skilled in the art to which the disclosed compositions and methods pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. It is understood, therefore, that the disclosure is not limited to the particular embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Those skilled in the art will recognize many variations and adaptations of the embodiments described herein. These variations and adaptations are within the teachings of the present disclosure and are intended to be encompassed by the scope of the claims herein.

[0015] Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0016]

[0013] As will be apparent to one skilled in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has individual components and features that can be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosure.

[0017] Any described method may be carried out in the order of events described or in any other order that is logically possible. That is, unless expressly stated otherwise, it is in no way intended that the methods or embodiments described herein be construed as requiring that its steps be performed in a particular order. Thus, unless a method claim specifically recites in the claim or description that the steps are limited to a particular order, no order is intended to be inferred in any respect. This also applies to all possible implicit bases for interpretation, including matters of logic regarding the arrangement of steps or operational flow, the plain meaning derived from grammatical construction or punctuation, or the number or type of embodiments described in the specification.

[0018]

[0015] It should also be understood that the terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosed compositions and methods belong. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of this specification and related art, and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0019] Prior to describing the various embodiments of the present disclosure, the following definitions are provided and should be used unless otherwise indicated. Additional terms may be defined elsewhere in this disclosure.

[0020] definition As used herein, "comprising" is interpreted as specifying the presence of the stated features, integers, steps, or components as referenced, but does not exclude the presence or addition of one or more features, integers, steps, or components, or groups thereof. Furthermore, each of the terms "by," "comprising," "comprises," "comprised of," "including," "includes," "included," "involving," "involves," "involved," and "such as" are used in their open, non-limiting sense and may be used interchangeably. Furthermore, the term "comprising" is intended to include examples and embodiments encompassed by the terms "consisting essentially of" and "consisting of." Similarly, the term "consisting essentially of" is intended to include examples encompassed by the term "consisting of."

[0021] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to an "elastomer," or a "vulcanizing agent" includes, but is not limited to, mixtures or combinations of two or more such elastomers or vulcanizing agents, and the like.

[0022] It should be noted that ratios, concentrations, amounts, and other numerical data may be expressed herein in a range format. It is further understood that the endpoints of each of the ranges are significant in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values ​​disclosed herein, and that each value is also disclosed herein as "about" that particular value in addition to the value itself. For example, if the value "10" is disclosed, then "about 10" is also disclosed. Ranges may be expressed herein as from "about" one particular value and / or to "about" another particular value. Similarly, when values ​​are expressed as approximations, the use of the antecedent "about" will understand that the particular value forms a further embodiment. For example, if the value "about 10" is disclosed, then "10" is also disclosed.

[0023]

[0020] When a range is expressed, a further embodiment includes from the one particular value and / or to the other particular value. For example, when the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure; for example, the phrase "from x to y" includes ranges from "x" to "y," as well as ranges greater than "x" and less than "y." Ranges may also be expressed as upper limits, e.g., "about x, y, z, or less," and should be interpreted to include the specific ranges of "about x," "about y," and "about z," as well as ranges of "less than x," "less than y," and "less than z." Similarly, the phrase "about x, y, z, or more" should be interpreted to include the specific ranges of "about x," "about y," and "about z," as well as ranges of "greater than x," "greater than y," and "greater than z." Furthermore, the phrase "about 'x' to 'y'," where "x" and "y" are numerical values, includes "about 'x' to about 'y'."

[0024] It should be understood that such range formats are used for convenience and brevity and, therefore, should be interpreted flexibly to include not only the numerical values ​​explicitly recited as the limits of the range, but also all individual numerical values ​​or subranges subsumed within that range, as if each numerical value and subrange were explicitly recited. By way of example, a numerical range of "about 0.1% to 5%" should be interpreted to include not only the explicitly recited values ​​of about 0.1% to about 5%, but also individual values ​​within the indicated range (e.g., about 1%, about 2%, about 3%, and about 4%), and subranges (e.g., about 0.5% to about 1.1%, about 5% to about 2.4%, about 0.5% to about 3.2%, and about 0.5% to about 4.4%, as well as other possible subranges).

[0025] As used herein, the terms “about,” “approximately,” “just or about,” and “substantially” mean that the quantity or value in question may be an exact value or a value that will provide an equivalent result or effect as recited in the claims or taught herein. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximated and / or larger or smaller, as desired, to reflect tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art to provide equivalent results or effects. In some circumstances, a value that will provide an equivalent result or effect may not be reasonably determined. In such cases, as used herein, “about” and “just or about” generally are understood to mean a ±10% variation of the stated nominal value, unless otherwise indicated or inferred. In general, a quantity, size, formulation, parameter, or other quantity or characteristic is “about,” “approximately,” or “just or about,” whether or not expressly stated as such. When "about," "approximately," or "just or about" is used before a quantitative value, unless specifically stated otherwise, it is understood that the parameter also includes the particular quantitative value itself.

[0026]

[0023] As used in this specification, the term "optional" or "optionally" means that the event or circumstance described thereafter may or may not occur, and that the description includes instances in which the event or circumstance occurs and instances in which it does not occur.

[0027] As used herein, the term "phr" refers to parts by weight of a respective material per 100 parts by weight of rubber or elastomer. Generally, using this convention, an elastomeric composition is composed of 100 parts by weight of rubber / elastomer. A claimed composition may contain rubbers / elastomers other than those expressly recited in the claims, provided that the phr values ​​of the claimed rubbers / elastomers comply with the claimed phr ranges and the amounts of all rubbers / elastomers in the composition total 100 parts rubber.

[0028]

[0025] The terms "rubber" and "elastomer" may be used interchangeably herein unless otherwise indicated.

[0029] As used herein, the "glass transition temperature" or "T" of an elastomer or rubber g " represents the glass transition temperature of the respective elastomer or rubber in the uncured state, or in the case of an elastomeric composition, in some embodiments, T g Tg can be measured in the cured state. Tg can be suitably determined as the peak midpoint by differential scanning calorimetry (DSC) according to ASTM D3418 or equivalent.

[0030] As used herein, the term "uncured composition" refers to an unvulcanized composition containing at least one natural or synthetic rubber component, and optionally one or more fillers, processing aids, or additional compounds. Uncured rubber is sensitive to temperature changes and tends to undergo "cold flow" (slow movement or deformation under stress) over time. In some embodiments, the uncured rubber composition is a masterbatch.

[0031] As used herein, the term "vulcanized rubber composition" refers to a rubber composition obtained by curing or vulcanizing the uncured compositions described herein, often accomplished in the presence of heat using sulfur compounds and / or other curing additives. Vulcanized or cured rubber does not undergo cold flow and is less sensitive to temperature changes compared to uncured rubber. In another embodiment, the rubber composition can be cured in a mold to form a finished article, including, but not limited to, a tire.

[0032] As used herein, the term "repeating unit" referred to in the partially saturated elastomers described herein is derived from the monomers used to produce the partially saturated elastomer. For example, polybutadiene has the repeating unit shown below, which may have a cis or trans stereochemical configuration.

[0033] [ka] In certain embodiments, when the partially saturated elastomer is the polymerization product of two different monomers (eg, A and B), the repeat unit can be represented by -AB-.

[0034] 2,2,4-trimethyl-1,2-dihydroquinoline, also referred to herein as TMDQ, has the following structure:

[0035] [ka]

[0036]

[0031] While the above structure depicts TMDQ as a monomer, oligomers composed of two or more repeating units of TMDQ (e.g., dimers, trimers, etc.) can be used as well. In one embodiment, a mixture of TMDQ oligomers and residual TMDQ monomers can be used as the antiozonants described herein. Examples of TMQDs useful herein include, but are not limited to, RUBATAN 184 manufactured by General Quimica (Spain), VULKANOX HS / LG manufactured by Lanxess (Germany), and polymerized trimethyldihydroquinoline silica manufactured by SHANDONG SUNSINE CHEMICALS (China).

[0037] Para-phenylenediamine compounds have the following general structure: [ka] where R and R' are independently hydrogen, an alkyl group, a cycloalkyl group, or an aryl group. An example of a para-phenylenediamine compound is N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD).

[0038] [ka]

[0039] Another example of a para-phenylenediamine antiozonant is DTPD, which is the reaction product of aniline and ortho-toluidine with hydroquinone. DTPD is a mixture of N,N'-o-tolyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, and N,N'-di-o-tolyl-p-phenylenediamine.

[0040] Unless otherwise specified, pressures referred to herein are based on atmospheric pressure (ie, 1 atmosphere).

[0041] rubber composition It has been discovered that the use of TMDQ or its oligomers in combination with partially saturated elastomers eliminates the need for traditional antiozonants, such as para-phenylenediamine compounds like 6PPD and DTPD. Accordingly, the rubber compositions described herein are free of para-phenylenediamine compounds. In one embodiment, TMDQ or its oligomers is the only antiozonant present in the rubber composition.

[0042] It has also been discovered that when small amounts of TMDQ or its oligomers are used in the absence of other antiozonants, rubber compositions having good physical properties are formed. In one embodiment, the rubber compositions described herein contain from about 2 phr to about 8 phr of TMDQ or its oligomers. In one embodiment, the rubber compositions described herein contain from about 2 phr, 2.5 phr, 3 phr, 3.5 phr, 4 phr, 4.5 phr, 5 phr, 5.5 phr, 6 phr, 6.5 phr, 7 phr, 7.5 phr, or 8 phr of TMDQ or its oligomers, any value being at the lower and upper ends of the range (e.g., 3 phr to 6 phr).

[0043] The degree of saturation of the partially saturated elastomer when used in combination with TMDQ or its oligomers affects the physical properties of the rubber composition.

[0044] In one embodiment, a partially saturated elastomer contains repeat units in which 15% or less of the total repeat units contain double bonds. In other embodiments, the amount of repeat units containing double bonds may be less than or equal to about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%, with any value representing the lower and upper ends of a range (e.g., 5% to 10%). When counting double bonds, double bonds in aromatic structures or groups, such as those present in styrene repeat units, are not included in the count. However, styrene units are still counted as repeat units for purposes of determining the total number of repeat units in the elastomer.

[0045] In one embodiment, the partially saturated elastomer may include repeat units formed by residues of monomers selected from one or more of ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof. In a further embodiment, the partially saturated elastomer is a hydrogenated styrene butadiene rubber, and in some embodiments, a hydrogenated solution polymerized styrene butadiene rubber (SSBR). The hydrogenated styrene butadiene rubber may have a styrene content of about 5 wt% to about 40 wt%, or about 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, or 40 wt%, any value being the lower or upper end of the range (e.g., 20 wt% to 40 wt%), and the butadiene content may be about 60 wt% to about 95 wt%, or about 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, or 95 wt%, any value being the lower or upper end of the range (e.g., 75 wt% to 90 wt%). In some embodiments, if 15% or less of the total repeat units of the SSBR contain double bonds, the SSBR may be referred to as a partially hydrogenated SSBR (HSBR).

[0046] In other embodiments, the HSBR can be characterized in that no more than about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15% of the total repeat units contain double bonds, any value being at the lower and upper ends of a range (e.g., 4% to 11%). HSBR also has a weight average molecular weight (M) of about 100 kg / mol to about 4,000 kg / mol, or 100 kg / mol, 200 kg / mol, 300 kg / mol, 400 kg / mol, 500 kg / mol, 600 kg / mol, 700 kg / mol, 800 kg / mol, 900 kg / mol, 1,000 kg / mol, 1,100 kg / mol, 1,200 kg / mol, 1,300 kg / mol, 1,400 kg / mol, 1,500 kg / mol, 2,000 kg / mol, 3,000 kg / mol, or 4,000 kg / mol. w), any value may be the lower or upper end of a range (e.g., 600 kg / mol to 900 kg / mol). In further embodiments, the HSBR may be characterized as having a polydispersity index (M) of about 1.05 to about 2.0, or 1.2, 1.4, 1.6, 1.8, or 2.0. w / M n , M n is the number average molecular weight), any value may be the lower or upper end of a range (e.g., 1.4 to 1.8). The molecular weight parameter may be determined by gel permeation chromatography according to ASTM 5296-11 using polystyrene calibration standards, or equivalent. In other embodiments, the HSBR may have a glass transition temperature of about -70°C to about -20°C, or about -70°C, -60°C, -50°C, -40°C, -30°C, or -20°C, any value may be the lower or upper end of a range (e.g., -60°C to -40°C).

[0047]

[0041] Partially saturated elastomers, in some embodiments, HSBR, can be obtained by hydrogenating an elastomer. The method for hydrogenating an elastomer may be carried out by any method known in the art. In one embodiment, hydrogenation is carried out by blowing aqueous hydrogen through an elastomer or polymer solution in the presence of a catalyst, such as a heterogeneous catalyst, a homogeneous catalyst, a catalyst using a metallocene such as a titanocene, or any combination thereof. Examples of heterogeneous catalysts include catalysts containing noble metals supported on porous inorganic materials. Examples of homogeneous catalysts include catalysts obtained by reacting solubilizing salts of nickel, cobalt, etc. with organoaluminum, etc. The degree of hydrogenation in the resulting elastomer can be controlled by varying factors such as the amount of hydrogen added, the hydrogen pressure, the reaction time, the reaction temperature, the amount of catalyst added, the viscosity of the polymer solution, or any combination thereof. In some embodiments, the hydrogenation reaction is carried out at a temperature of about 60°C to 105°C, or about 60°C, 70°C, 80°C, 90°C, 100°C, or 105°C, any value being at the lower or upper end of the range (e.g., 70°C to 100°C). In some embodiments, the hydrogenation reaction is carried out as a batch process, a continuous process, or a combination thereof. Additional details regarding the production of partially saturated elastomers are described in U.S. Patent Application Publication No. 2023 / 0138073 A1 and European Patent Application Publication No. 4261234 A1, which are incorporated herein by reference.

[0048] In one embodiment, the rubber composition comprises: 75 phr to 100 phr of partially saturated elastomers, and 0 phr to 25 phr of one or more of polybutadiene rubber, polyisoprene, hydrogenated styrene butadiene rubber, and natural rubber Includes:

[0049] In another embodiment, the partially saturated elastomer is i) less than 5% non-hydrogenated vinyl groups based on the total number of vinyl groups in the hydrogenated styrene butadiene rubber; ii) less than 20% of non-hydrogenated double bonds in the cis-1,4 and trans-1,4 butadiene repeat units, based on the total number of cis-1,4 and trans-1,4 butadiene repeat units; iii) 80% to 99% hydrogenated double bonds; and iv) a bound styrene content ranging from 5% to 40% by weight and a butadiene content ranging from 50% to 95% by weight The present invention includes a solution polymerized styrene butadiene rubber having one or more of the following:

[0050] The uncured rubber compositions described herein may contain additional ingredients typically employed in preparing rubber compositions. In one embodiment, the rubber composition may contain from about 5 phr to about 100 phr of silica. Various commercially available silicas may be used, including, but not limited to, those commercially available under the Hi-Sil trademark from PPG Industries under designations such as 210 and 243; those available from Solvay under designations such as Z1165MP, Z165GR, and Zeosil Premium 200MP; and those available from Degussa AG under designations such as VN2 and VN3. In other embodiments, blends of two or more silicas may be used, such as a blend of a relatively high surface area silica and a relatively low surface area silica.

[0051] In one embodiment, the uncured rubber composition may further comprise about 0.4 phr to about 15.0 phr of a vulcanizing agent, or about 0.4 phr, 3.0 phr, 6.0 phr, 9.0 phr, 12.0 phr, or 15.0 phr, any value being the lower or upper end of a range (e.g., 9.0 phr to 12.0 phr). In some embodiments, the vulcanizing agent comprises elemental sulfur, a sulfur-containing silane, or a combination thereof. Additionally, the uncured rubber composition may further comprise a vulcanization accelerator. Vulcanization accelerators are preferably used to control the time and / or temperature required for vulcanization and to improve the properties of the vulcanized composition, but are not necessarily used. The amount of vulcanization accelerator in the composition may be from about 0.3 phr to about 4.0 phr, or an amount of 0.3 phr, 1.0 phr, 2.0 phr, 3.0 phr, or 4.0 phr, any value being at the lower and upper ends of the range (e.g., 1.0 phr to 2.0 phr).

[0052] In some embodiments, the accelerator comprises a dithiocarbamate accelerator, a thiuram accelerator, a diphenylguanidine accelerator, a benzothiazole sulfenamide accelerator, or a combination thereof. The latent accelerator compound may include derivatives, e.g., a benzothiazole sulfenamide accelerator includes a benzothiazole sulfenamide, and may also include derivatives of benzothiazole sulfenamide. In other embodiments, the accelerator comprises an amine, a disulfide, a guanidine, a thiourea, a thiazole, a thiuram, a sulfenamide, a dithiocarbamate, and a xanthate. In another embodiment, the accelerator comprises a combination of a primary accelerator and a secondary accelerator, with the secondary accelerator being used in a smaller amount, e.g., 0.05 phr to 3.00 phr. In some embodiments, the secondary accelerator is selected from a guanidine, a dithiocarbamate, or a thiuram. Additionally, delayed action accelerators can be used that are not affected by normal processing temperatures but provide good cures at normal vulcanization temperatures.

[0053] In one embodiment, the uncured rubber composition can include additional components such as oil. In some embodiments, the oil is a process oil. The process oil may be included in the composition as an extender oil typically used to extend elastomers. The process oil may also be included in the elastomer composition by adding the oil directly during rubber compounding. The process oil used may include both the extender oil present in the elastomer and the process oil added during compounding. Suitable process oils include various oils known in the art, including, but not limited to, aromatic oils, paraffinic oils, naphthenic oils, vegetable oils, and low PCA oils, such as MES, TDAE, SRAE, and heavy naphthenic oils. Suitable low PCA oils include those having a polycyclic aromatic content of less than 3% by weight as determined by the IP346 method. The IP346 method procedure can be found in Standard Test Methods for Analysis and Testing of Petroleum and Related Products and British Standard 2000 Parts, 2003, 62nd Edition, published by the Institute of British Petroleum. Suitable TDAE oils are available as Tudalen SX500 from Klaus Dahleke KG, VivaTec 400 and VivaTec 500 from H&R Group, Enerthene 1849 from BP, and Extensoil 1996 from Repsol. The oils can be obtained alone or with elastomers in the form of extended elastomers. Suitable vegetable oils include, for example, soybean oil, sunflower oil, and canola oil, which are in the form of esters containing some degree of unsaturation.

[0054] In one embodiment, the rubber composition includes 3 phr to 20 phr of polyoctenamer. In another embodiment, the amount of polyoctenamer in the composition may be about 3 phr, 5 phr, 7 phr, 9 phr, 11 phr, 13 phr, 15 phr, 17 phr, or 20 phr, any value being at the lower and upper ends of a range (e.g., 7 phr to 17 phr).

[0055] In one embodiment, the polyoctenamer has a glass transition temperature in the range of −50° C. to −80° C., as determined in accordance with ASTM D3418, referenced below; a weight average molecular weight M in the range of 80,000 g / mol to 100,000 g / mol, as determined by gel permeation chromatography (GPC) using polystyrene calibration standards in accordance with ASTM 5296-11 or equivalent. W and a melting point in the range of 45° C. to 55° C. as measured by DSC with a second heat according to ASTM D3418 or equivalent. In another embodiment, the polyoctenamer has 65% to 85% trans double bonds of the total double bonds in the polyoctenamer.

[0056]

[0050] Described herein are vulcanized rubber compositions obtained by vulcanizing any of the uncured rubber compositions described herein. In one aspect, the vulcanized rubber compositions exhibit the same or reduced crack growth improvement when using TMDQ or its oligomers, compared to the same cured composition containing the same amount of para-phenylenediamine compound (e.g., 6PPD or DTPD). In one embodiment, the vulcanized rubber composition exhibits a 5% to 20% reduction in crack growth when using TMDQ or its oligomers, compared to the same cured composition containing the same amount of para-phenylenediamine compound, using the same test method. In another embodiment, the vulcanized rubber composition exhibits a 5%, 10%, 15%, or 20% reduction in crack growth when using TMDQ or its oligomers, compared to the same cured composition containing the same amount of para-phenylenediamine compound, using the same test method, with any value representing the lower and upper ends of a range (e.g., 10% to 20%). In one embodiment, ASTM D813 (pierced groove test or PG Flex) can be used to determine crack growth.

[0057] In another embodiment, the vulcanized rubber composition exhibits the same or a reduced crack growth improvement using the same test method when using a partially saturated elastomer in which 15% or less of the total repeating units of the partially saturated elastomer have double bonds, compared to the same cured composition containing a partially saturated elastomer in which more than 15% of the total repeating units of the partially saturated elastomer have double bonds. In one embodiment, the vulcanized rubber composition exhibits a 50% to 90% reduction in crack growth improvement using the same test method when using a partially saturated elastomer in which 15% or less of the total repeating units of the partially saturated elastomer have double bonds, compared to the same cured composition containing a partially saturated elastomer in which more than 15% of the total repeating units of the partially saturated elastomer have double bonds. In another embodiment, the vulcanized rubber composition exhibits an improvement of 50%, 60%, 70%, 80%, or 90% reduction in crack propagation when using a partially saturated elastomer in which 15% or less of the total repeating units of the partially saturated elastomer have double bonds, compared to the same cured composition containing a partially saturated elastomer in which more than 15% of the total repeating units of the partially saturated elastomer have double bonds, using the same test method.

[0058] In addition to reducing crack propagation, the use of TMDQ also reduces or prevents crack formation. As demonstrated in the examples, rubber compositions prepared using TMDQ and partially saturated elastomers in which 15% or less of the total repeating units of the partially saturated elastomer have double bonds are essentially crack-free. Similarly, the same rubber compositions prepared using 6PPD and DTPD as antiozonants are also essentially crack-free. Rubber compositions prepared with TMDQ have comparable ozone resistance compared to those prepared using conventional antiozonants such as 6PPD and DTPD. In one embodiment, ozone test methods such as DIN 53509 and DIN ISO 4131-1 can be used to evaluate crack formation.

[0059] Preparation and application of rubber compositions The compositions disclosed herein may be compounded by methods generally known in the rubber compounding art, such as by mixing the partially saturated elastomer and TMDQ or its oligomer with various commonly used additive materials, such as sulfur donors; cure aids, such as activators and retarders; processing additives, such as oils, resins (including tackifying resins) and plasticizers; fillers; pigments; fatty acids; zinc oxide; waxes; antioxidants; antiozonants; and peptizers, with various vulcanizable constituent rubbers. Zinc oxide may be included in amounts of about 1 phr to about 5 phr. Depending on the intended use of the vulcanizable and vulcanized materials (rubbers), the above additives are selected and commonly used in conventional amounts. In some embodiments, the tackifying resin is included in amounts of about 0.5 phr to 10 phr or about 1 phr to 5 phr. In some embodiments, the processing additives are included in amounts of about 1 phr to 50 phr. In some embodiments, the antioxidant is included in amounts of about 1 phr to 5 phr. Representative antioxidants include, but are not limited to, diphenyl-p-phenylenediamine, for example, those disclosed in The Vanderbilt Rubber Handbook, edited by Robert O. Babbit (Norwalk, Connecticut, R.T. Vanderbilt Company, Inc., 1978), pages 344-346. In some embodiments, the antiozonant is included in an amount of about 1 phr to 5 phr. Representative antiozonants include, but are not limited to, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD) and N,N'-o-tolyl-p-phenylenediamine (DTPD). In some embodiments, fatty acids are included in an amount of about 0.5 phr to 3 phr. Examples of useful fatty acids include stearic acid. In some embodiments, waxes are included in an amount of about 1 phr to 5 phr. Microcrystalline waxes may also be used. In some embodiments, the peptizer is present in an amount of about 0.1 phr to 1 phr. Typical peptizers include, for example, pentachlorothiophenol and dibenzamidodiphenyl disulfide.

[0060] The compositions disclosed herein can be mixed by methods known in the rubber mixing art. For example, the components may typically be mixed in at least two stages, i.e., at least one non-productive stage followed by a productive mix stage. In some embodiments, the mixing of the uncured composition includes only a single non-productive stage. The final curative, including the vulcanizing agent, may typically be mixed in a final stage, conventionally referred to as the "productive" mix stage, in which mixing is typically conducted at a temperature lower than, or at the ultimate temperature of, the preceding non-productive mix stage. In one embodiment, the elastomeric composition may be subjected to a thermomechanical mixing step. The thermomechanical mixing step generally involves mechanical work in a mixer or extruder for a suitable time to produce a rubber temperature, for example, in the range of about 140°C to 190°C. The appropriate duration of the thermomechanical work varies as a function of the operating conditions and the amount and nature of the components. For example, the thermomechanical work may be from about 1 to 20 minutes.

[0061] The present disclosure also provides articles incorporating any of the vulcanized rubber compositions disclosed herein. In some embodiments, the article comprises a tire, such as a pneumatic tire, or a tire component. The tire may be a race tire, passenger tire, aircraft tire, agricultural, earthmoving, off-road, truck tire, or the like. In one embodiment, the tire is a passenger or truck tire. The tire may also be radial or bias. The tire component may be a tread, base, apex, chafer, wire coat, innerliner, or any combination thereof. In another embodiment, the tire component comprising the composition is a tread, base, sidewall, or any combination thereof. Vulcanization of the disclosed tires is generally carried out at conventional temperatures ranging from about 100°C to about 200°C, or from about 110°C to about 180°C. Such tires may be built, shaped, molded, and cured by various methods known and readily apparent to those skilled in such art.

[0062]

[0056] Having generally described embodiments of the present disclosure above, the following examples describe some additional embodiments of the present disclosure. While embodiments of the present disclosure will be described in conjunction with the following examples and corresponding documents and figures, there is no intent to limit the embodiments of the present disclosure to this description. On the contrary, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the present disclosure.

[0063] Embodiment

[0057] The present disclosure can be described according to the following numbered embodiments, which should not be confused with the claims.

[0064] Embodiment 1. At least one partially saturated elastomer comprising repeat units, wherein no more than 15% of the total repeat units of the partially saturated elastomer contain double bonds; and 2,2,4-trimethyl-1,2-dihydroquinoline or its oligomer 1. An uncured composition comprising:

[0065]

[0059] Embodiment 2. The composition of embodiment 1, comprising from about 2 phr to about 8 phr of 2,2,4-trimethyl-1,2-dihydroquinoline or an oligomer thereof.

[0066]

[0060] Embodiment 3. The composition of embodiment 1 or 2, which does not contain a para-phenylenediamine compound.

[0067]

[0061] Embodiment 4. The composition of embodiment 1 or 2, wherein the para-phenylenediamine compound is 6PPD, DTPD, or any combination thereof.

[0068]

[0062] Embodiment 5. A composition described in any one of embodiments 1 to 4, wherein the partially saturated elastomer comprises repeating units formed by residues of monomers selected from one or more of ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof.

[0069]

[0063] Embodiment 6. A composition described in any one of embodiments 1 to 4, wherein the partially saturated elastomer is a partially hydrogenated styrene butadiene rubber.

[0070]

[0064] Embodiment 7. A composition described in any one of embodiments 1 to 6, wherein the partially saturated elastomer has a glass transition temperature of about -20°C to about -65°C.

[0071]

[0065] Embodiment 8. A composition described in any one of embodiments 1 to 7, wherein the partially saturated elastomer has a weight average molecular weight of 200,000 g / mol to 500,000 g / mol.

[0072]

[0066] Embodiment 9. A composition described in any one of embodiments 1 to 8, wherein about 4% to about 11% of all repeat units have double bonds.

[0073] Embodiment 10. 75 phr to 100 phr of a partially saturated elastomer, and 0 phr to 25 phr of one or more of polybutadiene rubber, polyisoprene, hydrogenated styrene butadiene rubber, and natural rubber 10. The composition of any one of embodiments 1-9, comprising:

[0074] Embodiment 11. The partially saturated elastomer is: i) less than 5% non-hydrogenated vinyl groups based on the total number of vinyl groups in the hydrogenated styrene butadiene rubber; ii) less than 20% of non-hydrogenated double bonds in the cis-1,4 and trans-1,4 butadiene repeat units, based on the total number of cis-1,4 and trans-1,4 butadiene repeat units; iii) 80% to 99% hydrogenated double bonds; and iv) a bound styrene content ranging from 5% to 40% by weight and a butadiene content ranging from 50% to 95% by weight 11. The composition of any one of the preceding embodiments, comprising a solution-polymerized styrene butadiene rubber having one or more of:

[0075]

[0069] Embodiment 12. The composition of any one of embodiments 1 to 11, further comprising silica in an amount of 10 phr to 100 phr.

[0076]

[0070] Embodiment 13. A composition described in any one of embodiments 1 to 12, further comprising 3 phr to 20 phr of polyoctenamer.

[0077]

[0071] Embodiment 14. The composition of any one of embodiments 1 to 13, further comprising a vulcanizing agent in an amount of 0.4 phr to 15.0 phr.

[0078]

[0072] Embodiment 15. The composition of any one of embodiments 1 to 14, further comprising a vulcanization accelerator in an amount of 0.3 phr to 4.0 phr.

[0079]

[0073] Embodiment 16. A vulcanized rubber composition comprising the uncured composition of any one of embodiments 1 to 15 that has been vulcanized.

[0080]

[0074] Embodiment 17. The composition of embodiment 16, having a PG Flex crack length at 180 minutes of about 3.0 mm to about 3.5 mm, as determined according to ASTM D813.

[0081]

[0075] Embodiment 18. The composition of embodiment 16, having a PG Flex crack length of about 4.0 mm to about 5.5 mm at 240 minutes, as determined according to ASTM D813.

[0082]

[0076] Embodiment 19. An article comprising the vulcanized rubber composition according to any one of embodiments 16 to 18.

[0083]

[0077] Embodiment 20. The article of embodiment 19, wherein the article comprises a tire or a tire component.

[0084]

[0078] Embodiment 21. The article of embodiment 20, wherein the tire components include a tread, a base, an apex, a chafer, a wire coat, an inner liner, or any combination thereof. [Example]

[0085] The following examples are set forth to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices, and / or methods claimed herein are made and evaluated. These examples are intended to be purely exemplary of the disclosure and are not intended to limit the scope of what the inventors regard as their disclosure. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless otherwise indicated, parts are parts by weight, temperature is ° C. or is ambient temperature, and pressure is at or near atmospheric.

[0086]

[0080] [Example 1] Comparison with various antiozonants

[0081] Four elastomer compositions containing a solution polymerized styrene butadiene rubber (SSBR)-based matrix are shown in Table 1. The most notable difference is that SSBR2 contains TMDQ as an antiozonant, while SSBR1 contains 6PPD and DTPD as antiozonants.

[0087]

[0082] In the case of SSBR3 and SSBR4, these compositions contain partially saturated elastomers in which more than 15% of the total repeat units of the partially saturated elastomer have double bonds, whereas SSBR2 contains partially saturated elastomers in which less than 15% of the total repeat units of the partially saturated elastomer have double bonds.

[0088] [Table 1]

[0089] Table 2 shows the crack resistance results for each rubber composition. As shown in Table 2, the use of TMDQ in SSBR2 shows an improvement in that crack growth is similar or reduced compared to the use of 6PPD and DTPD in SSBR1. Furthermore, SSBR2 shows an improvement in that crack growth is significantly reduced compared to SSBR3 and SSBR4. In fact, SSBR3 and SSBR4 completely crack in 240 minutes under the PG flex test (ASTM D813).

[0090] In addition to reducing crack propagation, the use of TMDQ reduces or prevents crack formation. Rubber composition SSBR2, prepared using TMDQ and a partially saturated elastomer containing repeating units, where 15% or less of the total repeating units of the partially saturated elastomer contain double bonds (i.e., the composition of the present invention), is essentially crack-free (Figure 2). Similarly, the same rubber composition (SSBR1; comparative example) prepared using 6PPD and DTPD as antiozonants is also essentially crack-free, as determined by DIN 53509 and DIN ISO 4131-1 (Figure 1). These results demonstrate that rubber compositions prepared using TMDQ have comparable ozone resistance to those prepared using conventional antiozonants, such as 6PPD and DTPD.

[0091] In another experiment, rubber compositions SSBR3 and SSBR4 were prepared using TMDQ in amounts of 3 phr and 5 phr, respectively, and a partially saturated elastomer containing repeating units, wherein more than 15% of the total repeating units of the partially saturated elastomer contained double bonds. SSBR3 and SSBR4 are comparative examples. SSBR3 and SSBR4 had numerous small cracks as determined by DIN 53509 and DIN ISO 4131-1 (FIGS. 3A and 3B, respectively).

[0092] Finally, the replacement of conventional antiozonants such as 6PPD and DTPD with TMDQ does not change the physical properties (dynamic and static) of both unaged and aged (90°C in air for 4 days) rubber compositions.

[0093] [Table 2]

[0094]

[0087] It should be emphasized that the above-described embodiments of the present disclosure are merely possible implementations, set forth for a clear understanding of the principles of the present disclosure. Many variations and modifications may be made to the above-described embodiments without substantially departing from the spirit and principles of the present disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.

Claims

1. at least one partially saturated elastomer comprising repeat units, wherein no more than 15% of the total repeat units of the partially saturated elastomer contain double bonds; and 2,2,4-trimethyl-1,2-dihydroquinoline or its oligomer 1. An uncured composition comprising:

2. 10. The composition of claim 1 comprising from about 2 phr to about 8 phr of 2,2,4-trimethyl-1,2-dihydroquinoline or an oligomer thereof.

3. The composition of claim 1, which is free of para-phenylenediamine compounds.

4. 4. The composition of claim 3, wherein the para-phenylenediamine compound is 6PPD, DTPD, or any combination thereof.

5. 10. The composition of claim 1, wherein the partially saturated elastomer comprises repeat units formed by residues of monomers selected from one or more of ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof.

6. The composition of claim 1 wherein the partially saturated elastomer is a partially hydrogenated styrene butadiene rubber.

7. The composition of claim 1, wherein the partially saturated elastomer has a glass transition temperature of from about -20°C to about -65°C.

8. The composition of claim 1, wherein the partially saturated elastomer has a weight average molecular weight of from 200,000 g / mol to 500,000 g / mol.

9. The composition of claim 1 , wherein from about 4% to about 11% of all repeat units have a double bond.

10. 75 phr to 100 phr of a partially saturated elastomer, and 0 phr to 25 phr of one or more of polybutadiene rubber, polyisoprene, hydrogenated styrene butadiene rubber, and natural rubber The composition of claim 1 comprising:

11. The partially saturated elastomer is i) less than 5% non-hydrogenated vinyl groups based on the total number of vinyl groups in the hydrogenated styrene butadiene rubber; ii) less than 20% non-hydrogenated double bonds in the cis-1,4 and trans-1,4 butadiene repeat units, based on the total number of cis-1,4 and trans-1,4 butadiene repeat units; iii) 80% to 99% hydrogenated double bonds; and iv) a bound styrene content ranging from 5% to 40% by weight and a butadiene content ranging from 50% to 95% by weight 10. The composition of claim 1, comprising a solution polymerized styrene butadiene rubber having one or more of:

12. The composition of claim 1 further comprising silica in an amount from 10 phr to 100 phr.

13. 10. The composition of claim 1 further comprising from 3 phr to 20 phr of a polyoctenamer.

14. The composition of claim 1 further comprising a vulcanizing agent in an amount from 0.4 phr to 15.0 phr.

15. The composition of claim 1 further comprising a vulcanization accelerator in an amount of 0.3 phr to 4.0 phr.

16. A vulcanized rubber composition comprising the uncured composition of claim 1 which has been vulcanized.

17. 17. The composition of claim 16, having a PG Flex crack length of from about 3.0 mm to about 3.5 mm at 180 minutes, as determined according to ASTM D813, or from about 4.0 mm to about 5.5 mm at 240 minutes, as determined according to ASTM D813.

18. 17. An article comprising the vulcanized rubber composition of claim 16.

19. 20. The article of claim 18, wherein the article comprises a tire or tire component.

20. 20. The article of claim 19, wherein the tire component comprises a tread, a base, an apex, a chafer, a wire coat, an innerliner, or any combination thereof.

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