Rubber compositions and articles thereof

Abstract

To provide elastomer compositions for tires that can provide good rolling resistance as well as good tensile strength, while at the same time maintaining desired stiffness of the material.SOLUTION: In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, the disclosure, in one aspect, relates to uncured compositions that include a partially saturated elastomer and a pre-silanized silica. In some aspects, the uncured compositions include about 40 phr to about 200 phr of the pre-silanized silica and at least one partially saturated elastomer including repeat units, where greater than 15% to about 30% of all repeat units of the partially saturated elastomer include a double bond. Also disclosed are vulcanized rubber compositions including the uncured compositions that have been vulcanized and articles including tires and / or components of tires comprising the vulcanized rubber compositions.SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002]

[0001] Due to the demand for improving tire performance, new materials having desired properties such as good rigidity and rolling resistance have been developed and evaluated. In a tire elastomer composition, improving the rolling resistance usually involves the cost of reducing the rigidity of the composition. It is difficult to improve properties such as rolling resistance and tensile strength while maintaining the balance of the trade-off. There is a need for a tire elastomer composition that provides good rolling resistance and good tensile strength while maintaining the desired rigidity of the material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Means for Solving the Problems

[0005]

[0002] In accordance with the objectives of the present disclosure, which are embodied and broadly described herein, the present disclosure, in one aspect, relates to an uncured composition comprising a partially saturated elastomer and a presilanized silica. In some aspects, the uncured composition comprises from about 40 phr to about 200 phr of presilanized silica and at least one partially saturated elastomer comprising repeating units, wherein more than 15% and up to about 30% of all the repeating units of the partially saturated elastomer contain double bonds. Also disclosed are a vulcanized rubber composition comprising the uncured composition after vulcanization, and an article comprising a tire and / or a tire component made from or comprising the vulcanized rubber composition.

[0006]

[0003] Other systems, methods, features and advantages of the present disclosure will be apparent to or will become apparent to those 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, are within the scope of the present disclosure, and are intended to be protected by the accompanying claims. In addition, all optional and preferred features and modifications of the described embodiments are usable in all aspects of the present disclosure taught herein. Further, the individual features of the dependent claims, as well as all optional and preferred features and modifications of the described embodiments, are combinable with each other and interchangeable.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]

[0004] Many modifications and other embodiments of the disclosure herein will come to mind to those of skill in the art to which the disclosed compositions and methods pertain, having the benefit of the teachings presented in the foregoing description and the related drawings. Accordingly, it is to be understood that the disclosure is not to be limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Those of ordinary skill in the art will recognize many variations and adaptations of the aspects described herein. These variations and adaptations are intended to be included within the teachings of the disclosure and are intended to be encompassed by the claims of this specification.

[0008]

[0005] Although certain terms are used in this specification, they are used only in a general and descriptive sense and are not intended to be limiting.

[0009]

[0006] As will be apparent to those skilled in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has separate components and features that can be readily separated from or combined with any of the features of some other embodiments without departing from the scope or spirit of the present disclosure.

[0010]

[0007] Any of the described methods may be performed in the order of the recited events or any other logically possible order. That is, unless explicitly stated otherwise, it is never intended that the methods or aspects described herein be construed as requiring that their steps be performed in a particular order. Thus, where a method claim does not specifically recite in the claims or description that the steps are limited to a particular order, no inference of order is ever intended in any respect. This is the same for any possible implicit basis for interpretation, including matters of logic regarding the arrangement of steps or the flow of operations, the plain meaning derived from grammatical construction or punctuation, or the number or type of aspects described in the specification.

[0011]

[0008] All publications referred to herein are incorporated herein by reference for the purpose of disclosing and describing the methods and / or materials related to which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing in this specification should be construed as an admission that the present invention is not entitled to antedate such publications by virtue of prior invention. Further, the publication dates provided herein may be different from the actual publication dates, which may require independent verification.

[0012] Aspects of the present disclosure may be described and claimed in terms of specific statutory classes, such as system statutory classes, but this is for convenience only, and those skilled in the art will understand that each aspect of the present disclosure may be described and claimed in any statutory class.

[0013] Also, it should be understood that the terms used herein are for the purpose of describing only particular aspects 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. Further, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that coincides with the meaning in the context of the present specification and the relevant art, and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0014] Before describing various aspects of the present disclosure, the following definitions are provided and should be used unless otherwise indicated. Additional terms may be defined elsewhere in the present disclosure.

[0015] Definitions As used herein, "comprising" is to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more features, integers, steps or components, or groups thereof. Further, the terms "by", "comprising", "comprises", "comprised of", "including", "includes", "included", "involving", "involves", "involved" and "such as" are each used in their open-ended non-limiting sense and may be used interchangeably. Further, the term "comprising" is intended to include examples and aspects subsumed by the terms "consisting essentially of" and "consisting of". Similarly, the term "consisting essentially of" is intended to include examples subsumed by the term "consisting of".

[0016] 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", "a pre-silanized silica", or "a vulcanizing agent" includes mixtures or combinations of two or more such elastomers, pre-silanized silicas, or vulcanizing agents, among others, but is not limited thereto.

[0017]

[0014] It should be noted that ratios, concentrations, amounts, and other numerical data can be expressed in range form in this specification. It is further understood that each endpoint of a range is significant in relation to, and independent of, the other endpoints. Also, there are a number of values disclosed in this specification, and each value is understood to be disclosed in this specification as "about" a particular value in addition to the value itself. For example, if the value "10" is disclosed, "about 10" is also disclosed. A range may be expressed in this specification as "about" one particular value to and / or "about" another particular value. Similarly, when a value is expressed as an approximation, it is understood that the use of the antecedent "about" forms additional embodiments for the particular value. For example, if the value "about 10" is disclosed, "10" is also disclosed.

[0018]

[0015] When a range is expressed, additional embodiments include from and / or to one particular value. For example, if the recited range includes one or both of the limiting values, ranges excluding one or both of the included limiting values are also included in the disclosure. For example, the phrase "x to y" includes the range from "x" to "y" and the range greater than "x" and less than "y". A range may also be expressed as an upper limit, for example, "about x, y, z, or less", and should be interpreted to include the particular ranges of "about x", "about y", and "about z", as well as the 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 particular ranges of "about x", "about y", and "about z", as well as the ranges of "greater than x", "greater than y", and "greater than z". Further, the phrase "about 'x' to 'y'" includes "about 'x' to about 'y'" when "x" and "y" are numerical values.

[0019]

[0016] Such a range format is used for convenience and brevity and should be understood to be interpreted flexibly so as to include not only the explicitly recited numerical values as the limits of the range, but also all individual numerical values or sub-ranges subsumed within that range as if each numerical value and sub-range were explicitly recited. By way of illustration, a numerical range of "about 0.1% to 5%" includes not only the explicitly recited values of about 0.1% to about 5%, but also the individual values within the indicated range (e.g., about 1%, about 2%, about 3%, and about 4%), as well as sub-ranges (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%, and other possible sub-ranges).

[0020]

[0017] As used herein, the terms "about," "approximately," "just or about," and "substantially" mean that the quantity or value in question can be the exact value, or a value that provides the equivalent result or effect as recited in the claims or taught herein. That is, quantities, sizes, formulations, parameters, and other quantities and characteristics are not exact and need not be exact, but can be approximations, and / or greater or less, as desired, reflecting tolerances, conversion factors, rounding, measurement errors, etc., and other factors known to those of ordinary skill in the art so as to provide the equivalent result or effect. In some situations, it may not be possible to reasonably determine a value that provides an equivalent result or effect. In such cases, as used herein, "about" and "just or about" generally mean a variation of ±10% of the indicated nominal value, unless otherwise indicated or inferred. Generally, a quantity, size, formulation, parameter, or other quantity or characteristic is "about," "approximately," or "just or about," whether or not so explicitly recited. When "about," "approximately," or "just or about" is used before a quantitative value, the parameter is understood to include the particular quantitative value itself, unless otherwise specified.

[0021] As used herein, the terms "optional" or "optionally" mean that the event or circumstance described thereafter may or may not occur, and the description is meant to include examples where the event or circumstance occurs and examples where it does not.

[0022]

[0019] As used herein, the term "phr" refers to the parts by weight of each material per 100 parts by weight of rubber or elastomer. Generally, using this convention, an elastomer composition is composed of 100 parts by weight of rubber / elastomer. The claimed composition may contain rubbers / elastomers other than those explicitly recited in the claims, provided that the phr values of the claimed rubber and elastomer are within the claimed phr ranges and the total amount of all rubbers / elastomers in the composition is 100 parts of rubber.

[0023]

[0020] The terms "rubber" and "elastomer" may be used interchangeably herein unless otherwise indicated.

[0024]

[0021] As used herein, the "glass transition temperature" or "T g " of an elastomer or rubber represents the glass transition temperature of the respective elastomer or rubber in the uncured state, or in the case of an elastomer composition, in some embodiments, T g can be measured in the cured state.

[0025]

[0022] As used herein, the term "uncured composition" refers to a composition that is not vulcanized and contains 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.

[0026] As used herein, the term "vulcanized rubber composition" refers to a rubber composition obtained by curing or vulcanizing the uncured compositions described herein, often using sulfur compounds and / or other curing additives, in the presence of heat. The vulcanized or cured rubber has not undergone cold flow and is less sensitive to temperature changes compared to the uncured rubber. In another aspect, the rubber composition can be cured in a mold to form finished products including, but not limited to, tires.

[0027] As used herein, the term "repeating unit" as referred to the partially saturated elastomers described herein is derived from the monomers used to produce the partially saturated elastomers. For example, polybutadiene has the repeating units provided below. [Chemical formula] In certain embodiments, when the partially saturated elastomer is a polymerization product of two different monomers (e.g., A and B), the repeating unit can be represented by -A-B-.

[0028] Unless otherwise specified, the pressures referred to herein are based on atmospheric pressure (i.e., 1 atmosphere).

[0029] Rubber composition It has been discovered that the combination of a partially saturated elastomer having an increased number of double bonds and a pre-silanized silica unexpectedly improves stiffness and hysteresis. Further, the use of the partially saturated elastomers described herein also improves tensile strength.

[0030]

[0027] The uncured compositions such as the uncured rubber composition described in this specification include a partially saturated elastomer and a pre-silanized silica. In some embodiments, the uncured composition includes from about 40 phr to about 200 phr of pre-silanized silica and at least one partially saturated elastomer containing repeating units, with more than 15% and up to about 30% of all the repeating units of the partially saturated elastomer containing double bonds. Also disclosed herein are vulcanized rubber compositions including the vulcanized uncured composition, and articles including tires and / or tire components made from or including the vulcanized rubber composition. The vulcanized or cured composition has good rolling resistance and tensile strength with little or no reduction in stiffness compared to a cured composition that does not include pre-silanized silica.

[0031]

[0028] In some embodiments, the partially saturated elastomer includes repeating units in which more than 15% and up to about 30% of all the repeating units contain double bonds. In other embodiments, the amount of repeating units containing double bonds may be about 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%, and any value may be the lower and upper endpoints of a range (e.g., 16% - 25%). When counting double bonds, double bonds in aromatic structures or groups such as those present in styrene repeating units are not included in the count. However, styrene units are still counted as repeating units to determine the total number of repeating units in the elastomer.

[0032]

[0029] In one aspect, the partially saturated elastomer can include repeating units formed by residues of one or more monomers selected from ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof. In a further aspect, the partially saturated elastomer is a hydrogenated styrene-butadiene rubber, and in some aspects is 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%, and any value may be the lower and upper endpoints of a range (e.g., 20 wt% to 40 wt%). The butadiene content is 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%, and any value may be the lower and upper endpoints of a range (e.g., 75 wt% to 90 wt%). In some aspects, if more than 15% and up to about 30% of the total repeating units of the SSBR contain double bonds, the SSBR may be referred to as a partially hydrogenated SSBR (HSBR).

[0033]

[0030] In other aspects, the HSBR may be characterized in that about 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30% of the total repeating units contain double bonds, and any value may be the lower and upper endpoints of a range (e.g., 18% to 23%). The HSBR also has a weight average molecular weight (M wIt may be characterized by having w / M n where M n is the number average molecular weight), and any value may be the lower and upper endpoints of a range (e.g., 1.4 to 1.8). The molecular weight parameters may be determined by gel permeation chromatography in accordance with ASTM 5296-11 using polystyrene calibration standards, or equivalents. 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, and any value may be the lower and upper endpoints of a range (e.g., -60 °C to -40 °C).

[0034]

[0031] In some embodiments, the partially saturated elastomer, such as HSBR, can be obtained by hydrogenating an elastomer. The method for hydrogenating the elastomer may be carried out by any method known in the art. In one embodiment, hydrogenation is carried out by blowing aqueous hydrogen into the 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 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 solubilized salts such as nickel and cobalt with organic aluminum. The degree of hydrogenation in the resulting elastomer can be controlled by varying factors such as the amount of hydrogen added, the pressure of hydrogen, 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, and any value may be the lower and upper endpoints 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 the partially saturated elastomer are described in US Patent Application Publication No. 2023 / 0138073A1 and European Patent Application Publication No. 4261234A1, which are incorporated herein by reference.

[0035]

[0032] In other embodiments, the compositions described herein can include from about 40 phr to about 200 phr of pre-silanized silica. In other embodiments, the composition can include from about 80 phr to about 130 phr of pre-silanized silica, or from about 40 phr, 60 phr, 80 phr, 100 phr, 130 phr, 160 phr, 190 phr, or 200 phr, and any value may be the lower and upper endpoints of the range (e.g., 100 phr to 160 phr). In some embodiments, the pre-silanized silica is from about 70 g / m 2 to about 200 g / m 2 or from about 70 g / m2 、 100 g / m 2 、 130 g / m 2 、 160 g / m 2 、 or 200 g / m 2 and has a BET surface area, where any value may be an endpoint at the lower and upper ends of a range (e.g., 130 g / m 2 ~ 200 g / m 2 ). In some embodiments, the pre-silanized silica is from about 120 g / m 2 to about 220 g / m 2 , or about 120 g / m 2 , 140 g / m 2 , 160 g / m 2 , 180 g / m 2 , 200 g / m 2 , or 220 g / m 2 and has a CTAB absorption surface area, where any value may be an endpoint at the lower and upper ends of a range (e.g., 140 g / m 2 ~ 200 g / m 2 ).

[0036]

[0033] In one embodiment, the pre-silanized silica may include silica having an alkylsilane, alkoxysilane, organoalkoxysilyl polysulfide, or organomercaptoalkoxysilane bonded to the silica. In other embodiments, the pre-silanized silica includes silica having a sulfur-containing silane bonded to the silica. In one embodiment, the sulfur-containing silane may include an alkoxyorganomercaptosilane or bis(3-triethoxysilylpropyl) polysulfide having an average of about 2 to 5 connecting sulfur atoms in the polysulfide crosslink. Examples of pre-silanized silica suitable for use in the compositions described herein include Ciptane® 255 LD and Ciptane® LP (PPG Industries); silica pretreated with mercaptosilane; Coupsil® 8113 (Degussa); Coupsil® 6508; and Agilon® 400, 454, and 458 silica from PPG Industries, but are not limited thereto.

[0037]

[0034] In some embodiments, the pre-silanized silica is treated with a silica dispersion aid. Such silica dispersion aids may include glycols, such as fatty acids, diethylene glycol, polyethylene glycol, fatty acid esters of hydrogenated or non-hydrogenated C5 or C6 sugars, and polyoxyethylene derivatives of fatty acid esters of hydrogenated or non-hydrogenated C5 or C6 sugars. Exemplary fatty acids may include stearic acid, palmitic acid, and oleic acid. Exemplary fatty acid esters of hydrogenated and non-hydrogenated C5 and C6 sugars (e.g., sorbose, mannose, and arabinose) may include sorbitan oleate (e.g., sorbitan monooleate, dioleate, trioleate, and sesquioleate), as well as sorbitan esters of lauric acid, palmitic acid, and stearic acid fatty acids, but are not limited thereto. Exemplary polyoxyethylene derivatives of fatty acid esters of hydrogenated and non-hydrogenated C5 and C6 sugars may include polysorbate and polyoxyethylene sorbitan esters, but are not limited thereto, and these are similar to the above-described fatty acid esters of hydrogenated and non-hydrogenated sugars, except that ethylene oxide groups are disposed at each of the hydroxyl groups. The silica dispersion aid may be present in an amount in the range of about 0.1 wt% to about 25 wt% based on the weight of the silica.

[0038]

[0035] In other embodiments, the pre-silanized silica is pre-hydrophobized by treating the silica in its aqueous colloidal form with both an organomercaptosilane and an alkylsilane in a weight ratio of 10 / 90 to 90 / 10 (organomercaptosilane to alkylsilane). In some embodiments, the alkylsilane has the general formula (I): X n -Si-R 1 4-n (I) (wherein R is an alkyl radical having 1 to 18 carbon atoms or 1 to 8 carbon atoms (e.g., methyl, ethyl, butyl, etc.), n is 1 to 3, and X is a radical selected from halogen and alkoxy radicals). In some embodiments, X is chlorine or bromine. In other embodiments, X is an alkoxy radical such as (R 2 O)-(wherein R 2 is an alkyl radical having 1 to 3 carbon atoms). In some embodiments, the organomercaptosilane has the general formula (II): (X) n (R 3 O) 3-n -Si-R 4 -SH (II) (wherein X is a radical selected from halogen and alkyl radicals having 1 to 16 carbon atoms, R 3 is an alkyl radical having 1 to 16 carbon atoms or 1 to 4 carbon atoms, R 4 is an alkylene radical having 1 to 16 carbon atoms or 1 to 4 carbon atoms (e.g., -(CH2) m -(where m is 1 to 16)), and n is 0 to 3). In some embodiments, X is chlorine or bromine. In other embodiments, X is an alkyl radical selected from methyl, ethyl, n-propyl, and n-butyl radicals. In other embodiments, R 4 is a propylene radical. In some embodiments, n is 0).

[0039] [

[0036] ]Typical alkylsilanes of formula (I) are trichloromethylsilane, dichlorodimethylsilane, chlorotrimethylsilane, trimethoxymethylsilane, dimethoxydimethylsilane, methoxymethylsilane, trimethoxypropylsilane, trimethoxyoctylsilane, trimethoxyhexadecylsilane, dimethoxydipropylsilane, triethoxymethylsilane, triethoxypropylsilane, triethoxyoctylsilane and diethoxydimethylsilane. Typical organomercaptosilanes of formula (II) are, for example, triethoxymercaptopropylsilane, trimethoxymercaptopropylsilane, methyldimethoxymercaptopropylsilane, methyldiethoxymercaptopropylsilane, dimethylmethoxymercaptopropylsilane, triethoxymercaptoethylsilane and tripropoxymercaptopropylsilane.

[0040] [

[0037] ]The uncured rubber composition may further comprise from about 0.4 phr to about 15.0 phr of a vulcanizing agent, or 0.4 phr, 3.0 phr, 6.0 phr, 9.0 phr, 12.0 phr, or 15.0 phr, and any value may be the lower and upper end points 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. Further, the uncured rubber composition may further comprise a vulcanization accelerator. The vulcanization accelerator can be preferably used to control the time and / or temperature required for vulcanization and to improve the properties of the vulcanized composition, but it is not necessarily used. The amount of the vulcanization accelerator in the composition may be from about 0.3 phr to about 4.0 phr, or 0.3 phr, 1.0 phr, 2.0 phr, 3.0 phr, or 4.0 phr, and any value may be the lower and upper end points of a range (e.g., 1.0 phr to 2.0 phr).

[0041]

[0038] In some embodiments, the vulcanization accelerator includes a dithiocarbamate accelerator, a thiuram accelerator, a diphenylguanidine accelerator, a benzothiazole sulfenamide accelerator, or a combination thereof. Potential vulcanization accelerator compounds may include derivatives. For example, a benzothiazole sulfenamide accelerator includes benzothiazole sulfenamide and may also include derivatives of benzothiazole sulfenamide. In other embodiments, the vulcanization accelerator includes amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamates, and xanthates. In another embodiment, the vulcanization accelerator includes a combination of a primary accelerator and a secondary accelerator, and the secondary accelerator is used in a smaller amount, for example, 0.05 phr to 3.00 phr. In some embodiments, the secondary accelerator is selected from guanidine, dithiocarbamate, or thiuram. Further, a delayed-action accelerator that is not affected by normal processing temperatures but provides good curing at normal vulcanization temperatures can be used.

[0042]

[0039] 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 commonly used for the extension of elastomers. The process oil may also be included in the elastomer composition by directly adding the oil during the compounding of the rubber. 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, but are not limited to, various oils known in the art such as 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 can include those having a polycyclic aromatic content of less than 3 wt% as determined by the IP346 method. The procedure for the IP346 method 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 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 oil can be obtained alone or in the form of an extended elastomer together with the elastomer. 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.

[0043]

[0040] This specification describes a vulcanized rubber composition obtained by vulcanizing any of the uncured rubber compositions described herein. In some embodiments, the vulcanized rubber composition has improved tensile strength as compared to a cured composition that does not contain pre-silanized silica. In a further embodiment, the tensile strength of the vulcanized composition disclosed herein is about 5% to about 20% greater (determined by ASTM D412), or has a tensile strength about 5%, 10%, 15%, 20%, 25% or 30% greater than that of a cured composition that does not contain pre-silanized silica, and any value may be an endpoint of the lower and upper bounds of a range (e.g., 10% to 15%).

[0044]

[0041] In other embodiments, the vulcanized rubber composition shows little or no reduction in stiffness as compared to a cured composition that does not contain pre-silanized silica, and may show an increase in stiffness in some embodiments. In a further embodiment, the vulcanized composition disclosed herein has a storage modulus G’ within about 10%, about 15%, or about 5% of that of a cured composition that does not contain pre-silanized silica when measured at 1% strain, 100 °C and a frequency of 1 Hz, based on ASTM D5289. The vulcanized composition may also have a tangent delta that is about 10% to about 40% lower, or about 10%, 15%, 20%, 25%, 30%, 35% or 40% lower than that of a cured composition that does not contain pre-silanized silica, and any value may be an endpoint of the lower and upper bounds of a range (e.g., 10% to 35%) based on DIN 53513, and the tangent delta is measured at 6% strain, 30 °C and a frequency of 7.8 Hz.

[0045] Preparation and Application of Rubber Compositions

[0042] The compositions disclosed herein may be compounded by methods generally known in the art of rubber compounding, such as mixing a partially saturated elastomer and a pre-silanized silica with a sulfur donor; curing 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 various commonly used additive materials such as mastication accelerators. Zinc oxide may be included in an amount 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 generally used in conventional amounts. In some embodiments, the tackifying resin is included in an amount of about 0.5 phr to 10 phr or about 1 phr to 5 phr. In some embodiments, the processing additives are included in an amount of about 1 phr to 50 phr. In some embodiments, the antioxidant is included in an amount of about 1 phr to 5 phr. Representative antioxidants include, but are not limited to, diphenyl-p-phenylenediamine, as disclosed, for example, in The Vanderbilt Rubber Handbook (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'-dixylene-p-phenylenediamine (DTPD). In some embodiments, the fatty acid is included in an amount of about 0.5 phr to 3 phr. Examples of fatty acids used include stearic acid. In some embodiments, the wax is included in an amount of about 1 phr to 5 phr. Microcrystalline wax may be used. In some embodiments, the mastication accelerator is included in an amount of about 0.1 phr to 1 phr. Typical mastication accelerators include, for example, pentachlorothiophenol and dibenzamidodiphenyldisulfide.

[0046] [

[0043] ]The compositions disclosed herein can be mixed by methods known in the art of rubber mixing technology. For example, the components may be mixed in typically at least two stages, i.e., a non-productive stage followed by a productive mixing stage. In some embodiments, the mixing of the uncured composition includes only a single non-productive stage. The final curing agent, including the vulcanizing agent, is typically mixed in the final stage, conventionally called the "productive" mixing stage, at a temperature lower than the mixing temperature of the non-productive mixing stage that typically precedes the mixing, or at the temperature reached. In one embodiment, the elastomeric composition may be subjected to a thermomechanical mixing step. The thermomechanical mixing step generally includes mechanical work in a mixer or extruder for a time suitable to provide a rubber temperature in the range of, for example, 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 about 1 to 20 minutes.

[0047] [

[0044] ]The present disclosure also provides an article incorporating any of the vulcanized rubber compositions disclosed herein. In some embodiments, the article includes a tire, such as a pneumatic tire, or a component of a tire. The tire may be a racing tire, a passenger tire, an aircraft tire, an agricultural, geotechnical, off-road, truck tire, etc. In one embodiment, the tire is a passenger or truck tire. The tire may also be radial or bias. The components of the tire may be a tread, a base, a sidewall, an apex, a chafer, a sidewall insert, a wire coat, an inner liner, or any combination thereof. In another embodiment, the components of the tire incorporating the composition are a tread, a base, a sidewall, or any combination thereof. The vulcanization of the disclosed tires is generally carried out at conventional temperatures in the range of about 100 °C to about 200 °C, or about 110 °C to about 180 °C. Such tires are known and may be constructed, shaped, molded, and cured by various methods readily apparent to those skilled in such art.

[0048]

[0045] Although aspects of the present disclosure have been generally described above, in the following examples, some additional aspects of the present disclosure will be described. The aspects of the present disclosure are described in connection with the following examples and corresponding documents and figures, but there is no intention to limit the aspects of the present disclosure to this description. In contrast, the intention is to cover all alternatives, modifications, and equivalents that are included within the spirit and scope of the present disclosure.

[0049] Aspect

[0046] The present disclosure can be described according to the following numbered aspects, which should not be confused with the claims.

[0050]

[0047] Aspect 1. At least one partially saturated elastomer containing repeating units, wherein more than 15% and up to about 30% of all the repeating units of the partially saturated elastomer contain double bonds, at least one partially saturated elastomer, and About 40 phr to about 200 phr of pre-silanized silica An uncured composition comprising.

[0051]

[0048] Aspect 2. The composition according to Aspect 1, wherein about 16% to about 25% of all the repeating units of the partially saturated elastomer contain double bonds.

[0052]

[0049] Aspect 3. The composition according to Aspect 1 or 2, wherein the partially saturated elastomer comprises repeating units formed by residues of one or more monomers selected from ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof.

[0053]

[0050] Aspect 4. The composition according to Aspect 1 or 2, wherein the partially saturated elastomer is a partially hydrogenated styrene-butadiene rubber.

[0054]

[0051] Aspect 5. The composition according to Aspect 4, wherein the partially hydrogenated styrene-butadiene rubber has about 16% to about 25% of repeating units containing double bonds.

[0055]

[0052] Aspect 6. The composition according to Aspect 4 or 5, wherein the partially hydrogenated styrene-butadiene rubber has a styrene content of about 5 wt% to about 40 wt% of the partially hydrogenated styrene-butadiene rubber and a butadiene content of about 60 wt% to about 95 wt% of the partially hydrogenated styrene-butadiene rubber.

[0056]

[0053] Aspect 7. The composition according to any one of Aspects 4 to 6, wherein the partially hydrogenated styrene-butadiene rubber has a glass transition temperature of about -70 °C to about -20 °C.

[0057]

[0054] Aspect 8. The composition according to any one of Aspects 4 to 7, wherein the hydrogenated styrene-butadiene rubber has a weight average molecular weight of about 100 kg / mol to about 4000 kg / mol.

[0058]

[0055] Aspect 9. The composition according to any one of Aspects 4 to 7, wherein the partially hydrogenated styrene-butadiene rubber has an average molecular weight of about 100 kg / mol to about 1500 kg / mol.

[0059]

[0056] Aspect 10. The composition according to any one of Aspects 1 to 9, comprising about 80 phr to about 130 phr of pre-silanized silica.

[0060]

[0057] Aspect 11. The composition according to any one of Aspects 1 to 10, wherein the pre-silanized silica has a BET surface area of about 70 g / m 2 ~ about 200 g / m 2

[0061]

[0058] Aspect 12. The composition according to any one of Aspects 1 to 11, wherein the pre-silanized silica has a CTAB adsorption surface area of about 120 g / m 2 ~ about 220 g / m 2

[0062] Aspect 13. The composition according to any one of Aspects 1 to 12, wherein the pre-silanized silica comprises silica having an alkylsilane, alkoxysilane, organoalkoxysilyl polysulfide, or organomercaptoalkoxysilane bonded to the silica.

[0063] Aspect 14. The composition according to any one of Aspects 1 to 12, wherein the pre-silanized silica comprises silica having a sulfur-containing silane bonded to the silica.

[0064] Aspect 15. The composition according to Aspect 14, wherein the sulfur-containing silane comprises bis(3-triethoxysilylpropyl) polysulfide containing an average of about 2 to 5 connecting sulfur atoms during its polysulfide crosslinking, or an alkoxyorganomercaptosilane.

[0065] Aspect 16. The composition according to any one of Aspects 1 to 15, further comprising a vulcanizing agent in an amount of 0.4 phr to 15.0 phr.

[0066] Aspect 17. The composition according to Aspect 16, wherein the vulcanizing agent comprises elemental sulfur, a sulfur-containing silane, or a combination thereof.

[0067] Aspect 18. The composition according to any one of Aspects 1 to 17, further comprising a vulcanization accelerator in an amount of 0.3 phr to 4.0 phr.

[0068] Aspect 19. The composition according to Aspect 18, wherein the vulcanization accelerator comprises a dithiocarbamate accelerator, a thiuram accelerator, a diphenylguanidine accelerator, a benzothiazole sulfenamide accelerator, or a combination thereof.

[0069] Aspect 20. A vulcanized rubber composition comprising the uncured composition according to any one of Aspects 1 to 19.

[0070] Aspect 21. The composition according to aspect 20, which has a tensile strength that is about 5% to about 20% greater than that of a cured composition without the pre-silanized silica when determined by ASTM D412.

[0071] Aspect 22. The composition according to aspect 20 or 21, wherein the storage modulus G' at 1% strain, 100 °C, and a frequency of 1 Hz, based on ASTM D5289, is within 10% of that of a cured composition without the pre-silanized silica.

[0072] Aspect 23. The composition according to any one of aspects 20 to 22, wherein the tangent delta at 6% strain, 30 °C, and a frequency of 7.8 Hz, based on DIN 53513, is about 10% to about 40% lower than that of a cured composition without the pre-silanized silica.

[0073] Aspect 24. An article comprising the vulcanized rubber composition according to any one of aspects 20 to 23.

[0074] Aspect 25. The article according to aspect 24, wherein the article comprises a tire or a tire component.

[0075] Aspect 26. The article according to aspect 25, wherein the tire component comprises a tread, a base, a sidewall, an apex, a chafer, a sidewall insert, a wire coat, an inner liner, or any combination thereof.

[0076] Aspect 27. The article according to aspect 25, wherein the tire component comprises a tread, a base, a sidewall, or any combination thereof.

Examples

[0077]

[0074] The following examples are set forth to provide those skilled in the art with a complete disclosure and description of how the compounds, compositions, articles, devices, and / or methods claimed in this specification are made and evaluated. These examples are intended purely as illustrative of the disclosure and are not intended to limit what the inventors regard as the 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 in °C or ambient temperature, and pressure is at or near atmospheric pressure.

[0078] [Example 1] Rubber composition

[0075] Table 1 shows two elastomer compositions containing a solution-polymerized styrene-butadiene rubber (SSBR)-based matrix. Most of the components of the two compositions are the same. The most notable difference is that SSBR2 contains pre-silanized silica, while SSBR1 contains an equivalent amount of conventional silica, i.e., non-pre-silanized silica.

[0079]

[0076] Table 2 shows the rheological properties of the SSBR1 and SSBR2 compositions. There is no change in tensile strength between the two compositions. The tangent delta value is reduced by about 14% in the composition containing pre-silanized silica and is improved compared to the composition containing conventional silica. Since tangent delta can be regarded as a hysteresis index, this reduction also indicates that the rolling resistance is reduced in the tire containing the vulcanized SSBR2 composition compared to the tire containing the vulcanized SSBR1 composition. Unfortunately, the stiffness of the SSBR2 composition is much lower than that of the SSBR1 composition, and G’ is reduced by about 34% in SSBR2 compared to SSBR1. The use of pre-silanized silica in the elastomer composition improves silica dispersion, thus introducing this trade-off (improvement in hysteresis in exchange for low strain stiffness). The reduction in hysteresis is a positive result of the introduction of pre-silanized silica, but the significant decrease in stiffness may be a problem for many performance-oriented tire applications.

[0080]

Table 1

[0081]

Table 2

[0082]

[0077] Table 3 shows two elastomer compositions containing a partially hydrogenated SSBR (HSBR) - based matrix (about 77% hydrogenated). Most of the components of the two compositions are the same. The most significant difference is that HSBR2 contains pre - silanized silica, while HSBR1 contains an equivalent amount of conventional silica, i.e., non - pre - silanized silica.

[0083]

[0078] Table 4 shows the rheological properties of the HSBR1 and HSBR2 compositions. Similar to SSBR1 and 2, the tangent delta value decreases in the composition containing pre - silanized silica compared to the composition containing conventional silica. However, in the HSBR compositions, when using pre - silanized silica, the decrease in tangent delta is more significant (about 29%). Also, the rigidity of HSBR2, which is a pre - silanized silica composition, has a G’ decrease of less than 10% compared to the change in rigidity from SSBR1 to SSBR2 and is very close to the rigidity of HSBR1. Surprisingly, the HSBR2 composition also shows an increase in tensile strength compared to HSBR1. It is difficult to achieve the improvement in tensile strength while also improving the hysteresis properties. HSBR2 has good rigidity, good rolling resistance index, and good tensile strength.

[0084]

Table 3

[0085]

Table 4

[0086]

[0079] It should be emphasized that the above-described embodiments of the present disclosure are merely possible implementation examples described for the purpose of clearly understanding the principles of the present disclosure. Many modifications and variations can 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 within the scope of the present disclosure herein and be protected by the following claims.

Claims

1. At least one partially saturated elastomer comprising repeating units, wherein more than 15% and up to about 30% of all the repeating units of the partially saturated elastomer contain double bonds, at least one partially saturated elastomer, and About 40 phr to about 200 phr of pre-silanized silica An uncured composition comprising.

2. The composition according to claim 1, wherein about 16% to about 25% of all the repeating units of the partially saturated elastomer contain double bonds.

3. The composition according to claim 1, wherein the partially saturated elastomer comprises repeating units formed from residues of one or more monomers selected from ethylene, propylene, butadiene, isoprene, styrene, and any combination thereof.

4. The composition according to claim 1, wherein the partially saturated elastomer is a partially hydrogenated styrene-butadiene rubber.

5. The composition according to claim 4, wherein the partially hydrogenated styrene-butadiene rubber has about 15% to about 25% of repeating units containing double bonds.

6. The composition according to claim 4, wherein the partially hydrogenated styrene-butadiene rubber has a styrene content of about 5 wt% to about 40 wt% of the partially hydrogenated styrene-butadiene rubber and a butadiene content of about 60 wt% to about 95 wt% of the partially hydrogenated styrene-butadiene rubber.

7. The composition according to claim 4, wherein the partially hydrogenated styrene-butadiene rubber has a glass transition temperature of about -70°C to about -20°C.

8. The composition according to claim 4, wherein the partially hydrogenated styrene-butadiene rubber has a weight average molecular weight of about 100 kg / mol to about 1500 kg / mol.

9. The composition according to claim 1, comprising about 80 phr to about 130 phr of pre-silanized silica.

10. The preliminary silanized silica has a BET surface area of about 70 g / m ２ to about 200 g / m ２ The composition according to claim 1.

11. The composition according to claim 1, wherein the preliminary silanized silica has a CTAB adsorption surface area of about 120 g / m ２ to about 220 g / m ２ .

12. The composition according to claim 1, wherein the pre-silanized silica comprises silica having an alkylsilane, alkoxysilane, organoalkoxysilyl polysulfide, or organomercaptoalkoxysilane bonded thereto.

13. The composition according to claim 1, wherein the pre-silanized silica comprises silica having a sulfur-containing silane bonded thereto.

14. The composition according to claim 13, wherein the sulfur-containing silane comprises bis(3-triethoxysilylpropyl) polysulfide containing an average of about 2 to 5 connecting sulfur atoms during polysulfide crosslinking, or an alkoxyorganomercaptosilane.

15. The composition according to claim 1, further comprising a vulcanizing agent in an amount of 0.4 phr to 15.0 phr.

16. The composition according to claim 1, further comprising an accelerator in an amount of 0.3 phr to 4.0 phr.

17. A vulcanized rubber composition comprising the uncured composition according to claim 1.

18. An article comprising the vulcanized rubber composition according to claim 17.

19. The article according to claim 18, wherein the article comprises a tire or a tire component.

20. The article according to claim 19, wherein the tire component comprises a tread, a base, a sidewall, or any combination thereof.

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