Method for preparing silica-natural rubber master batch

Abstract

In one aspect, the present disclosure relates to a method for preparing a masterbatch comprising natural rubber or other rubber and silica. In one aspect, silica is subjected to a chemical treatment or other treatment to reduce the ability of silica particles to form hydrogen bonds. On the other hand, silica is then mixed with water and subjected to ultrasonic vibration to produce an emulsive silica solution. In yet another aspect, the milky silica solution is then mixed with a natural rubber latex or other rubber latex to achieve efficient dispersion of silica in the rubber matrix. The silica solution and the rubber matrix are dehydrated and / or dried to obtain a masterbatch material that can be immediately used to prepare a cured rubber article or can be stored for future use without degradation or separation. Also disclosed are master batch materials and rubber articles prepared using the master batch materials, such as, for example, tires.

Description

Technical Field

[0001] This invention relates to a method for preparing a masterbatch material comprising surface-modified silica and rubber latex, the masterbatch material prepared by the method, an uncured rubber composition, a cured rubber composition, and articles thereof. Background Technology

[0002] The compounding of natural rubber with silica presents numerous challenges, including but not limited to batch-to-batch variability, high compound viscosity, and changes in masterbatch properties during storage. Desiredly, a method for dispersing silica in natural rubber (NR) or other rubber matrices would ensure batch-to-batch homogeneity, improve viscosity during mixing compatible with existing machinery, and allow for masterbatch storage without altering its properties. This disclosure addresses these and other needs. Summary of the Invention

[0003] According to one or more of the purposes of this disclosure, as embodied and broadly described herein, this disclosure relates in one aspect to a method for preparing a masterbatch comprising natural rubber or other rubber and silica. On one hand, the silica is chemically or otherwise treated to reduce the ability of the silica particles to form hydrogen bonds. On the other hand, the silica is then mixed with water and subjected to ultrasonic vibration to generate an emulsion silica solution. In another aspect, this emulsion silica solution can then be mixed with natural rubber latex or other rubber latex to achieve effective dispersion of silica in a rubber matrix. The silica solution and the rubber matrix are dehydrated and / or dried to obtain a masterbatch material that can be immediately used to prepare cured rubber articles or stored for future use without degradation or separation. The masterbatch material and rubber articles made using the masterbatch material, such as tires, are also disclosed.

[0004] Other systems, methods, features, and advantages of this disclosure will be apparent to those skilled in the art after examining the following figures and detailed descriptions. All such additional systems, methods, features, and advantages are intended to be included within this specification, within the scope of this disclosure, and protected by the appended claims. Furthermore, all optional and preferred features and modifications of the described embodiments are applicable to all aspects of the disclosure taught herein. Moreover, the various features of the dependent claims, as well as all optional and preferred features and modifications of the described embodiments, are combinable and interchangeable with each other.

[0005] The present invention discloses the following solutions: Option 1. A method for preparing a masterbatch material comprising surface-modified silica and rubber latex, the method comprising: (a) The surface-modified silica is mixed with water, and the surface-modified silica and water are subjected to ultrasonic treatment to prepare a silica solution; (b) Blending the silica solution with the rubber latex to obtain a second solution; and (c) Remove water from the second solution to obtain masterbatch material; The surface-modified silica contains fewer surface-exposed hydrogen-bonded groups than other identical unmodified silica.

[0006] Option 2. The method according to Option 1, wherein the surface-modified silica includes surface modification containing one or more silanes.

[0007] Option 3. The method according to Option 2, wherein the one or more silanes comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyl octane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyoxyethylene polyurethane, (3-mercaptopropyl)-triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide, triethoxyallylsilane, or any combination thereof.

[0008] Option 4. The method according to Option 1, wherein the surface-modified silica comprises a surface modification containing a surfactant, a hydrophobic polymer film, a silane-containing coupling agent and an ethoxylated alcohol ether, or any combination thereof.

[0009] Option 5. A masterbatch material prepared by the method described in Option 1.

[0010] Option 6. The masterbatch material according to Option 5, wherein the rubber latex comprises natural rubber latex, emulsion styrene-butadiene rubber (eSBR), or any combination thereof.

[0011] Scheme 7. An uncured rubber composition comprising the masterbatch material described in Scheme 5.

[0012] Option 8. A cured rubber composition comprising the uncured rubber composition of Option 7, followed by a curing step.

[0013] Option 9. An article comprising the cured rubber composition described in Option 8.

[0014] Option 10. The article of claim 9, wherein the article comprises a tire.

[0015] Option 11. The method according to Option 4, wherein the silane-containing coupling agent comprises 3-mercaptopropyltriethoxysilane, S-[3-(triethoxysilyl)propyl]octyl sulfate, bis(trialkoxysilylalkyl)polysulfide, bis(alkoxyaryloxysilylalkyl)polysulfide, bis(triaryloxysilylalkyl)polysulfide, or any combination thereof.

[0016] Option 12. The method according to Option 4, wherein the hydrophobic polymer film comprises plasma-polymerized 1,7-octadiene.

[0017] Option 13. The method according to Option 4, wherein the surfactant comprises stearic acid.

[0018] Option 14. The method according to Option 1, wherein the ultrasonic treatment is performed at room temperature for about 5 minutes to about 30 minutes.

[0019] Option 15. The method according to Option 1, wherein step (b) comprises mechanical mixing, high-shear mixing, or any combination thereof, and wherein step (b) is performed for about 10 minutes to about 60 minutes.

[0020] Option 16. The method according to Option 1, wherein the silica solution comprises about 10 parts by weight to about 30 parts by weight of surface-modified silica and about 150 parts by weight of water.

[0021] Option 17. The method according to Option 1, wherein step (c) includes dewatering using sieving, pressing, rolling, extrusion or any combination thereof.

[0022] Option 18. The method according to Option 1, wherein the masterbatch material does not separate during storage for at least 24 hours.

[0023] Option 19. The masterbatch material according to Option 6, wherein the natural rubber latex comprises silver guar gum rubber latex, dandelion (Taraxacum kok-saghyz) (TKS) rubber latex, Russian dandelion rubber latex, or any combination thereof.

[0024] Option 20. The masterbatch material according to Option 5, wherein the masterbatch material comprises silica particles of about 10 phr to about 130 phr. Attached Figure Description

[0025] Many aspects of this disclosure can be better understood by referring to the following accompanying drawings. The components in the drawings are not necessarily drawn to scale, but rather the emphasis is on clearly illustrating the principles of this disclosure. Furthermore, in the drawings, the same reference numerals indicate corresponding parts throughout multiple views.

[0026] Figure 1 This is a flowchart of the disclosed method.

[0027] Additional advantages of the invention will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and obtained by means of the elements and combinations particularly pointed out in the appended claims. It should be understood that the foregoing summary and the following detailed description are merely exemplary and illustrative, and do not limit the invention as claimed. Detailed Implementation

[0028] Many modifications and other embodiments of the disclosed compositions and methods will arise to those skilled in the art from the teachings presented in the foregoing description and related drawings. Therefore, it should be understood that this disclosure is not 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 skilled in the art will recognize many variations and modifications to the aspects described herein. These variations and modifications are intended to be included in the teachings of this disclosure and are covered by the claims herein.

[0029] Although specific terms are used in this document, they are used only in a general and descriptive sense, and not for restrictive purposes.

[0030] As will be apparent to those skilled in the art upon reading this disclosure, each individual embodiment described and illustrated herein has discrete components and features that can be readily separated from or combined with features of any of the other plurality of embodiments without departing from the scope or spirit of this disclosure.

[0031] Any enumerated method may be performed in the order of the enumerated events or in any other logically possible order. That is, unless otherwise expressly stated, it is never intended to interpret any method or aspect described herein as requiring its steps to be performed in a particular order. Therefore, unless a method claim in the claim or specification specifically states that the steps will be limited to a particular order, no inference is made in any respect of the order. This applies to any possible non-explicit basis of interpretation, including the logical content of the arrangement of steps or procedures, the simple meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

[0032] All publications mentioned herein are incorporated herein by reference to disclose and describe methods and / or materials relating to the cited publications. The publications discussed herein provide only their disclosure prior to the filing date of this application. This document should not be construed as an admission that the invention is not authorized prior to these publications by virtue of prior invention. Furthermore, the publication dates provided herein may differ from the actual publication dates, which may require independent verification.

[0033] While aspects of this disclosure may be described and claimed under specific statutory categories such as the systems statutory category, this is merely for convenience, and those skilled in the art will understand that each aspect of this disclosure may be described and claimed under any statutory category.

[0034] It should also be understood that the terminology used herein is for descriptive purposes only and is 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 pertain. It will be further understood that terms as defined in common dictionaries should be interpreted as having the same meaning as they have in the context of the specification and the relevant field, and should not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0035] Before describing various aspects of this disclosure, the following definitions are provided and should be used unless otherwise specified. Additional terms may be defined elsewhere in this disclosure.

[0036] definition As used herein, “comprising” should be interpreted as specifying the presence of the mentioned feature, integer, step, or component, but does not preclude the presence or addition of one or more features, integers, steps, or components, or groups thereof. Furthermore, each of the terms “through,” “comprising,” “comprises,” “comprised of,” “including,” “includes,” “included,” “involving,” “involves,” “involved,” and “such as” is used in its open, non-limiting sense and is interchangeable. Additionally, the term “comprising” is intended to include instances and aspects covered by the terms “substantially constitutes” and “consistent with.” Similarly, the term “substantially constitutes” is intended to include instances covered by the term “consistent with.”

[0037] As used in the specification and appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Thus, for example, references to “filler,” “curing accelerator,” or “alcohol ether” include, but are not limited to, mixtures or combinations of two or more such fillers, curing accelerators, or alcohol ethers.

[0038] It should be noted that ratios, concentrations, amounts, and other numerical data may be expressed in ranges herein. It will be further understood that each endpoint of a range is meaningful both relative to and independent of another endpoint. It should also be understood that many values ​​are disclosed herein, and each value is also disclosed herein as “about” that particular value, in addition to being the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. In this document, a range may be expressed as from “about” one particular value and / or to “about” another particular value. Similarly, when a value is expressed as an approximation using the antecedent “about”, it will be understood that the particular value forms another aspect. For example, if the value “about 10” is disclosed, then “10” is also disclosed.

[0039] When indicating a range, on the other hand, it includes a range from one specific value and / or to another specific value. For example, where the range includes one or two limits, the range excluding any one or both of those included limits is also included in this disclosure; for example, the phrase "x to y" includes the range from "x" to "y" as well as the range greater than "x" and less than "y". A range can also be expressed as an upper limit, such as "about x, y, z or less", and should be interpreted as including the specific 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 greater" should be interpreted as including the specific 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". Furthermore, the phrase "about "x" to "y" (where "x" and "y" are numerical values) includes "about "x" to about "y".

[0040] It should be understood that this range form is used for convenience and brevity, and therefore should be interpreted flexibly to include not only the values ​​explicitly listed as the boundaries of the range, but also all individual values ​​or subranges contained within that range, as if each value and subrange were explicitly listed. For example, the range of values ​​“about 0.1% to 5%” should be interpreted to include not only the explicitly stated values ​​of about 0.1% to about 5%, but also individual values ​​(e.g., about 1%, about 2%, about 3%, and about 4%) and subranges within the indicated range (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 subranges).

[0041] As used herein, the terms “about,” “approximately,” “in or about,” and “substantially” mean that the quantity or value in question can be an exact value or value that provides an equivalent result or effect as described in the claims or taught herein. That is, it should be understood that quantities, dimensions, formulations, parameters, and other quantities and characteristics are not and need not be exact, but can be approximate and / or larger or smaller as needed, reflecting tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art, resulting in an equivalent result or effect. In some cases, it is not reasonable to determine a value that provides an equivalent result or effect. In such cases, it is generally understood that, as used herein, “about” and “in or about” mean a variation of ±10% of the indicated nominal value, unless otherwise indicated or inferred. Generally, quantities, dimensions, formulations, parameters, or other quantities or characteristics are “about,” “approximately,” or “in or about,” whether or not explicitly stated so. It should be understood that, unless otherwise specifically stated, when “about,” “approximately,” or “in or about” is used before a quantity value, the parameter also includes the specific quantity value itself.

[0042] As used herein, the terms “optional” or “optionally” mean that the event or situation described below may or may not occur, and the description includes both the possibility that the event or situation occurs and the possibility that it does not occur.

[0043] As used herein, the term "phr" and by convention refers to the weight parts of the corresponding material in 100 parts by weight of rubber or elastomer. Typically, using this convention, a rubber or elastomer composition comprises 100 parts by weight of rubber / elastomer. The claimed composition may contain other rubber / elastomers besides those expressly mentioned in the claims, provided that the phr value of the claimed rubber elastomer falls within the claimed phr range and the total amount of all rubber / elastomers in the composition results in a total of 100 parts of rubber. For example, the composition may further contain 1 to 10 phr, optionally 1 to 5 phr, of one or more additional diene-based rubbers, such as SBR, SSBR, ESBR, PBD / BR, NR, and / or synthetic polyisoprene. In other instances, the composition may contain less than 5 phr, preferably less than 3 phr, of additional diene-based rubber, or substantially no such additional diene-based rubber. Unless otherwise stated, the terms "rubber" and "elastomer" may be used interchangeably herein.

[0044] As used herein, the term "uncured rubber composition" refers to a composition comprising at least one natural or synthetic rubber component and optionally one or more fillers, processing aids, or other compounds, which has not been vulcanized. Uncured rubber is sensitive to temperature changes and tends to undergo "cold flow" (slow movement or deformation under stress) over time. In some respects, uncured rubber compositions are masterbatches.

[0045] As used herein, the term "cured rubber composition" refers to a rubber composition obtained by taking an uncured rubber composition and curing or vulcanizing it, typically using sulfur compounds and / or other curing additives and done in the presence of heat. Vulcanized or cured rubber does not undergo a cold flow and is less sensitive to temperature changes compared to uncured rubber. On the other hand, rubber compositions can be cured in molds to form finished articles, including but not limited to tires.

[0046] As used herein, "surface-modified silica" refers to silica products obtained by chemically or physically modifying untreated silica to alter its properties (such as hydrogen bonding). On the one hand, untreated silica may have a large number of exposed hydroxyl groups and / or other chemical groups that can participate in hydrogen bonding, which can affect the dispersibility of silica in water and may lead to agglomeration or precipitation of silica in aqueous solutions, suspensions, and / or slurries. On the other hand, and not bound by theory, the surface of modified silica can allow silica to be stably dispersed in water, which in turn can facilitate the mixing of silica aqueous solutions with natural rubber latex or other rubber latexes, while reducing viscosity and making it easier to mix.

[0047] Unless otherwise stated, the temperatures mentioned in this article are based on atmospheric pressure (i.e., one atmosphere).

[0048] Method for manufacturing masterbatch materials On the one hand, this article discloses a method for manufacturing a masterbatch material comprising surface-modified silica and rubber latex, the method comprising at least the following steps: (a) Surface-modified silica is mixed with water and the surface-modified silica and water are subjected to ultrasonic treatment to prepare a silica solution; (b) Blending a silica solution with a rubber latex to obtain a second solution; and (c) Remove water from the second solution to obtain masterbatch material.

[0049] On the one hand, the ultrasonic treatment is performed at room temperature. On the other hand, the ultrasonic treatment is performed for approximately 5 to approximately 30 minutes, or approximately 5 to approximately 25 minutes, or approximately 10 to approximately 20 minutes, or approximately 5, 10, 15, 20, 25 or approximately 30 minutes.

[0050] On the other hand, step (b) includes mechanical mixing, high-shear mixing, other mixing methods, or any combination thereof. On the other hand, step (b) is carried out for about 10 minutes to about 60 minutes, or about 10 minutes to about 45 minutes, about 15 minutes to about 30 minutes, or about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or about 60 minutes.

[0051] On one hand, the silica solution contains about 10 parts by weight to about 30 parts by weight of surface-modified silica, or about 10 parts by weight to about 25 parts by weight, or about 15 parts by weight to about 20 parts by weight, or about 10, 15, 20, 25 or about 30 parts by weight of surface-modified silica. On the other hand, the silica solution contains about 15 parts by weight of water.

[0052] On the other hand, step (c) can be carried out using screening, pressing, rolling, extrusion or any combination thereof, or any other dewatering method known in the art.

[0053] The masterbatch material prepared by the disclosed method and the uncured rubber composition containing the masterbatch are also disclosed. Figure 1 An exemplary method for preparing this masterbatch material is shown. Furthermore, this document discloses a cured rubber composition comprising an uncured rubber composition after a curing step. The individual components of this rubber composition will be described in more detail below.

[0054] Masterbatch material On the one hand, the disclosed masterbatch materials include natural rubber latex, emulsion styrene-butadiene rubber (eSBR), or any combination thereof. On the other hand, when the masterbatch material contains natural rubber latex, the natural rubber latex may be selected from silver guar gum rubber latex, dandelion (Taraxacum kok-saghyz) (TKS) rubber latex, Russian dandelion rubber latex, or any combination thereof.

[0055] On the other hand, emulsion polymerization of styrene / butadiene (eSBR) can be used, wherein the styrene content of eSBR is from about 5% to about 50%, or from about 8% to about 28% of bound styrene. eSBR, in this context, refers to styrene and 1,3-butadiene copolymerized as an aqueous emulsion.

[0056] On the one hand, when used herein, references are made to the glass transition temperature or Tglass transition temperature of the elastomer or elastomer composition. g T represents the glass transition temperature of the corresponding elastomer or elastomer composition in its uncured state, or, in some respects, for the elastomer composition, T g It can be measured in the cured state. On the one hand, T gThe midpoint of the peak can be properly determined using a differential scanning calorimeter (DSC) with a test standard (such as ASTM D7426 or an equivalent standard).

[0057] On the other hand, the masterbatch material can be used immediately after preparation or stored for later use. In either of these respects, the masterbatch material will not separate after being stored for at least 1 hour, at least 6 hours, at least 12 hours, or at least 24 hours after preparation.

[0058] Surface-modified silica and its preparation On the one hand, this paper envisions many examples of surface-modified silica, and these examples should be considered as disclosed. On the other hand, surface-modified silica contains fewer surface-exposed hydrogen-bonded groups (such as hydroxyl groups) than other identical but untreated silica. On the other hand, surface-modified silica can be chemically modified, or it can be physically modified (e.g., through non-covalent interactions), or both.

[0059] In some respects, surface-modified silica includes surface modification incorporating one or more silanes. On the other hand, the one or more silanes may be selected from triethoxy(octyl)silane, 1,8-bis(triethoxysilyl)octane, (3-glycidyloxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyoxyethylene polyurethane, (3-mercaptopropyl)triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide, triethoxyallylsilane, or any combination thereof.

[0060] On the other hand, surface-modified silica includes surface modification incorporating surfactants, hydrophobic polymer films, silane-containing coupling agents, and ethoxylated alcohol ethers, or any combination thereof. On one hand, the hydrophobic polymer film may be 1,7-octadiene or contain 1,7-octadiene. On the other hand, the surfactant may be stearic acid.

[0061] On the one hand, untreated silica is used to prepare the surface-modified silica described herein. On the other hand, untreated silica can be a pre-washed wet filter cake of precipitated silica with hydroxyl groups on it. Alternatively, precipitated silica can be derived from rice husk ash or bagasse (sugarcane ash), etc., and does not require drying after washing and filtration with acid-treated sodium silicate.

[0062] On the one hand, untreated silica can have particle sizes of less than 10 micrometers (μm), or less than 5 μm, or less than 0.1 μm, as determined by ASTM C721-20, "Standard Test Methods for Estimating Average Particle Size of Alumina and Silica Powders by Air Permeability." (Primary silica particles used in rubber are typically in the range of 10 to 100 nanometers, or 0.01 to 0.1 micrometers), as measured by differential centrifugal sedimentation (DCS).

[0063] Exemplary untreated precipitated silica can be obtained from PPG Industries as Hi-Sil™, for example, under the names 210, 243, 315, EZ 160G-D, EZ 150G, 190G, 200G-D, HDP-320G, and 255CG-D; as Zeosil™ from Solvay, under the names 115GR, 125GR, 165GR, 175GR, 185GR, 195GR, 1085GR, 1165MP, 1115MP, HRS1200MP, Premium MP, Premium 200MP, and 195HR; as Ultrasil™ from Evonik, under the names VN2, VN3, VN3GR, 5000GR, 7000GR, and 9000GR; as Zeopol™, under the names 8755LS and 8745; and as Newsil™ from WuxiQuechen Silicon Chemical. Co., Ltd., named 115GR and 2000MP; obtained as Tokusil™ 315 from Maruo Calcium Co., Ltd.; and rice husk ash derived silica from Yihai Food and Oil Industry, China. Any precipitated silica can be used in this method. In other embodiments, untreated precipitated silica is prepared as a wet filter material shortly before use.

[0064] In some respects, organosilanes or silane-containing coupling agents are used to prepare the surface-modified silica described herein. On the other hand, the silane-containing coupling agent may be selected from 3-mercaptopropyltriethoxysilane, S-[3-(triethoxysilyl)propyl]octanethioate, bis(trialkoxysilyl)alkyl polysulfides, bis(alkoxyaryloxysilyl)alkyl polysulfides, bis(triaryloxysilyl)alkyl polysulfides, or any combination thereof.

[0065] One exemplified coupling agent comprises one or more alkoxy groups, such as a methoxy group or an ethoxy group (or more), which are directly bonded to silicon atoms. In such coupling agents, the alkoxy groups are hydrolyzed in the presence of moisture typically present on a silica surface to form a corresponding silanol, which reacts on or condenses in the presence of the silica surface to bond silicon atoms to the silica surface. Thus, one or more organic groups attached to the silicon atoms can chemically react with the polymer matrix during vulcanization. Therefore, the polymer matrix can be chemically bonded to silica particles by means of the coupling agent, for example, during polymer curing or vulcanization.

[0066] On one hand, the amount of silane coupling agent used to form surface-modified silica can be at least 0.01 parts by weight per 100 parts by weight of filler (“phr”, referring to untreated silica). In some embodiments, the amount of silica coupling agent can be at least 1 phr, or at least 2 phr, or at least 5 phr, or at least 8 phr, or at least 10 phr, or at most 50 phr, or at most 15 phr (2 to 15 phr) of untreated precipitated silica. On the other hand, the weight ratio of coupling agent to alcohol ether can be at least 0.8:1, or at least 1:1, or at least 1.2:1, or at most 3:1 (0.8:1 to 10:1). On the other hand, since the coupling agent and alcohol ether remain on the silica when the mixture is spray-dried, their respective amounts and phr can be readily determined from the amount of coupling agent and alcohol ether added to the slurry and the dry weight of the surface-modified silica product.

[0067] In another embodiment, the masterbatch material described herein comprises at least 10 phr, or at least 20 phr, or at least 50 phr, or at most 130 phr, or at most 120 phr, or at most 110 phr, or at most 100 phr. In other words, the pretreated silica may comprise at least 2% by weight, or at least 5% by weight, or at least 10% by weight, or at least 20% by weight, or at most 60% by weight, or at most 40% by weight of the total formulated rubber composition.

[0068] Additional components On the one hand, in addition to carbon black and surface-modified silica, or otherwise, the rubber composition described herein may contain reinforcing fillers of up to 10 phr. On the other hand, the processing aids used to form the rubber composition may include at least one of resin, wax, and liquid plasticizer. On the one hand, the curing package may include at least one of sulfur-based vulcanizing agents and curing accelerators, curing activators, and curing inhibitors. On the other hand, the curing package may include peroxide-based vulcanizing agents. On the other hand, the rubber composition may further include at least one of antioxidants, anti-degradation agents, and anti-ozone agents. In some aspects, the rubber composition may be used to form tires and / or tire treads.

[0069] On the one hand, the rubber composition comprises 100 phr vulcanizable elastomer; at least 5 phr pretreated silica; optionally, one or more other reinforcing fillers, one or more processing aids, and a sulfur-containing curing package.

[0070] In some aspects, the rubber composition may contain up to 100 phr of processing oil. In one embodiment, the amount of processing oil ranges from about 1 phr to about 40 phr. In an alternative embodiment, the rubber composition does not contain processing oil. On the other hand, the processing oil may be included in the rubber composition as an extender oil typically used for elastomer extension, or the oil may be added directly during rubber compounding. In some aspects, the processing oil used may include extender oils present in the elastomer and processing oils added during compounding. On the other hand, suitable processing oils include a variety of oils known in the art, including aromatic oils, paraffinic oils, naphthenic oils, and low-PCA oils such as MES, TDAE, and heavy naphthenic oils, as well as vegetable oils such as sunflower oil, soybean oil, and safflower oil.

[0071] On the one hand, the rubber composition may contain low-PCA oil. Suitable low-PCA oils include, but are not limited to, mild extraction solvates (MES), treated distillate aromatic extracts (TDAE), and heavy naphthenic oils as known in the art. Typically, suitable low-PCA oils include those with a glass transition temperature T0. g Those in the range of approximately -20°C to approximately -80°C. MES oil T g Typically, it ranges from approximately -57°C to approximately -63°C. TDAE oil's T... g Typically, the temperature range is from approximately -44°C to approximately -50°C. The T... g Typically, it ranges from approximately -42°C to approximately -48°C. TDAE oil's T... g The appropriate measurement method is DSC according to ASTM E1356 or equivalent standards.

[0072] On the one hand, suitable low-PCA oils include those with a polycyclic aromatic hydrocarbon content of less than 3% by weight as determined by the IP 346 method. The procedure for the IP 346 method can be found in the British Petroleum Institute's Standard Methods for Analysis and Testing of Petroleum and Related Products and British Standards 2000 Part 62 (2003).

[0073] 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. These oils can be obtained alone or as extended elastomers in combination with elastomers. Suitable vegetable oils include, for example, soybean oil, sunflower oil, and rapeseed oil, which exist in the form of esters containing a certain degree of unsaturation.

[0074] On the one hand, the disclosed rubber composition may contain about 50 phr to about 150 phr of silica (i.e., untreated silica, excluding surface-modified silica as described herein). In some aspects, precipitated silica is preferred, such as silica obtained, for example, by acidification of soluble silicates (e.g., sodium silicate). On the other hand, such conventional silica may be characterized, for example, by having a BET surface area (e.g., measured using nitrogen gas) preferably about 40 m² / g to about 600 m² / g, or about 50 m² / g to about 300 m² / g. On the other hand, conventional silica may also typically be characterized by having a dibutyl phthalate (DBP) absorbance value of about 100 to about 400, or about 150 to about 300.

[0075] Conventional silica is expected to have an average final particle size, for example, in the range of 0.01 micrometers to 0.05 micrometers as determined by electron microscopy, although in some cases silica particles may have larger or smaller diameters.

[0076] Various commercially available silicas may be used, such as (for illustrative purposes only and not as a limitation) silicas commercially available under the trademark Hi-Sil from PPG Industries, under names such as 210, 243, 315, etc.; silicas available from Rhodia, under names such as Z1165MP and Z165GR; and silicas available from Degussa AG, under names such as VN2 and VN3, etc.

[0077] On the one hand, the rubber composition may optionally contain carbon black of about 1 phr to about 70 phr. Commonly used carbon blacks can be used as conventional fillers. Representative examples of such carbon blacks include N110, N121, N134, N220, N231, N234, N242, N293, N299, N315, N326, N330, N332, N339, N343, N347, N351, N358, N375, N539, N550, N582, N630, N642, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990, and N991. These carbon blacks have an iodine absorption range of approximately 9 g / kg to approximately 145 g / kg, and a DBP value range of approximately 34 cm⁻¹. 3 / 100 g to approximately 150 cm 3 / 100g.

[0078] Other fillers may be used in the rubber composition, including but not limited to particulate fillers, such as ultra-high molecular weight polyethylene (UHMWPE), particulate polymer gel and plasticized starch composite filler.

[0079] Preparation and application of rubber compositions It will be readily understood by those skilled in the art that the disclosed rubber compositions can be compounded by methods commonly known in the field of rubber compounding, such as mixing various sulfur-vulcanizable component rubbers with various commonly used additive materials, such as, for example, sulfur donors, curing aids (e.g., activators and retarders), fillers, pigments, fatty acids, zinc oxide, waxes, antioxidants and anti-ozone agents, and solvents. As those skilled in the art know, the above-mentioned additives are selected according to the intended use of the sulfur-vulcanizable and sulfur-vulcanizable materials (rubbers) and are generally used in conventional amounts.

[0080] Representative examples of sulfur donors include elemental sulfur (free sulfur), amine disulfides, polymeric polysulfides, and sulfur olefin adducts. In one embodiment, the sulfur-sulfurizing agent is elemental sulfur. The sulfur-sulfurizing agent can be used in amounts ranging from about 0.5 phr to about 8 phr, or from about 1.5 phr to about 6 phr. Typical amounts of antioxidants can be from about 1 phr to about 5 phr. Representative antioxidants may be, for example, diphenyl-p-phenylenediamine. Typical amounts of anti-ozone agents are from about 1 phr to about 5 phr. If fatty acids are used, typical amounts are from about 0.5 phr to about 3 phr. On one hand, available fatty acids include, but are not limited to, stearic acid. Typical amounts of zinc oxide are from about 2 phr to about 5 phr. Typical amounts of waxes are from about 1 phr to about 5 phr. Microcrystalline waxes are typically used. Typical amounts of colloidal solvents are from about 0.1 phr to 1 phr. Typical colloidal solvents may be, for example, pentachlorothiophenol and dibenzoylamino diphenyl disulfide.

[0081] In some respects, accelerators can be used to control the time and / or temperature required for vulcanization and to improve the properties of the vulcanized rubber. In one embodiment, a single accelerator system, i.e., a primary accelerator, can be used. The primary accelerator can be used in a total amount ranging from about 0.5 phr to about 4 phr, or from about 0.8 phr to about 1.5 phr. In another embodiment, a combination of a primary accelerator and a secondary accelerator can be used, wherein the secondary accelerator is used in a smaller amount, such as from about 0.05 phr to about 3 phr, to activate and improve the properties of the vulcanized rubber. These combinations of accelerators can be expected to produce a synergistic effect on the final properties and are better than those rubbers prepared using either accelerator alone. On the other hand, delayed-action accelerators can be used; these accelerators are not affected by normal processing temperatures but produce satisfactory curing at ordinary vulcanization temperatures.

[0082] In some aspects, vulcanization delay agents may also be used. Suitable types of accelerators that can be used in this invention are amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfonamides, dithiocarbamates, and xanthate compounds. In one embodiment, the primary accelerator is a sulfonamide. If a secondary accelerator is used, it may be a guanidine, a dithiocarbamate (ester), or a thiuram compound.

[0083] The mixing of rubber compositions can be accomplished by methods known to those skilled in the art of rubber compounding. For example, the components are typically mixed in at least two stages: at least one non-productive mixing stage followed by a productive mixing stage. Vulcanizing agents, including final vulcanizing agents, are typically mixed in a final stage, conventionally referred to as the "productive" mixing stage, where mixing is typically carried out at a temperature lower than the mixing temperature of the preceding non-productive mixing stages or at the final temperature. The terms "non-productive" and "productive" mixing stages are well known to those skilled in the art of rubber compounding.

[0084] In some respects, rubber compositions can undergo a thermomechanical mixing step. A thermomechanical mixing step typically involves mechanical work for a suitable period in a mixer or extruder to produce a rubber temperature of about 140°C to about 190°C. The suitable duration of the thermomechanical work depends on the operating conditions and the volume and type of the components. For example, the thermomechanical work can be from about 1 minute to about 20 minutes.

[0085] On the other hand, the rubber composition can be incorporated into various rubber components of the tire. For example, the rubber component can be the tread (including the crown and base), sidewall, triangular strip, bead wrap, sidewall insert, steel wire coating, or airtight layer. In one embodiment, the component is the tread. The pneumatic tire of the present invention can be a racing tire, passenger tire, aircraft tire, agricultural tire, bulldozer tire, off-road tire, truck tire, etc. In one embodiment, the tire is a passenger tire or a truck tire. The tire can also be radially or twill-patterned.

[0086] The vulcanization of the disclosed pneumatic tires is typically carried out at conventional temperatures of about 100°C to about 200°C or about 110°C to about 180°C. Such tires can be manufactured, shaped, molded, and cured by a variety of known and obvious methods to those skilled in the art.

[0087] Having now described various aspects of this disclosure, the following embodiments generally illustrate some additional aspects of this disclosure. While various aspects of this disclosure will be described in conjunction with the following embodiments and corresponding text and drawings, this is not to imply that the aspects of this disclosure will be limited to these descriptions. Rather, it is intended to cover all alternatives, modifications, and equivalents included within the spirit and scope of this disclosure. Example

[0088] The following examples are provided to provide those skilled in the art with a complete disclosure and description of how to prepare and evaluate the compounds, compositions, articles, apparatus, and / or methods claimed herein. The following examples are intended to be illustrative of this disclosure only and are not intended to limit the scope of the disclosure as the inventors believe it to be. Efforts have been made to ensure accuracy regarding figures (e.g., quantities, temperatures, etc.), but some errors and deviations should be accounted for. Unless otherwise stated, parts are parts by weight, temperatures are in °C or at ambient temperature, and pressures are at or near atmospheric pressure.

[0089] Example 1: Method for manufacturing masterbatch material In the control experiment, 20 g of chemically treated silica was added to 150 g of deionized water. The mixture was shaken at room temperature for 1 hour. The turbid liquid was allowed to stand for 5 minutes, and precipitation was observed.

[0090] In another experiment, 20 g of chemically treated silica was added to 150 g of deionized water. The mixture was subjected to ultrasonic vibration at room temperature for 10 minutes. An emulsion solution was formed, which was stable and did not separate for at least one day.

[0091] Example 2: Rubber Composition and its Preparation The stable, ultrasonically treated emulsion solution from Example 1 was thoroughly mixed with natural rubber latex using mechanical mixing, high-shear mixing, or other methods. The composition was then fed to a stripping unit to remove water and / or dry, thereby obtaining a masterbatch. A summary diagram of the method is shown below. Figure 1 As shown. After approximately 10 minutes of mechanical mixing, the natural rubber / silica masterbatch material self-solidifies.

[0092] Example 3: Preparation of cured rubber and / or rubber products The rubber composition was prepared by mixing in a Banbury mixer. The initial mixing stage included a masterbatch as disclosed herein. In conventional (control) mixing, natural rubber and silica, along with other rubber compound components (excluding sulfur-based rubber curing agents), were mixed in at least one step (often referred to as a “non-productive” mixing stage) to reach high temperatures under high-shear rubber mixing conditions, followed by a final “productive” mixing step or stage in which sulfur-based curing packets, such as sulfur and sulfur curing accelerators, were added and mixed with them at lower mixing temperatures to avoid unnecessary pre-curing of the rubber mixture during the mixing stage.

[0093] It should be emphasized that the above embodiments of this disclosure are merely possible examples of implementation methods described for the purpose of clearly understanding the principles of this disclosure. Many changes and modifications can be made to the above embodiments without substantially departing from the spirit and principles of this disclosure. All such modifications and changes are intended to be included within the scope of this disclosure and protected by the appended claims.

Claims

1. A method for preparing a masterbatch material comprising a surface-modified silica and a rubber latex, the method comprising: (a) admixing the surface-modified silica with water and subjecting the surface-modified silica and water to ultrasonication to produce a silica solution; (b) admixing the silica solution with the rubber latex to obtain a second solution; and (c) removing water from the second solution to obtain a masterbatch material; wherein the surface-modified silica comprises fewer surface-exposed hydrogen bonding groups than an otherwise identical unmodified silica.

2. The method of claim 1, wherein the surface-modified silica comprises a surface modification comprising one or more silanes.

3. The method of claim 2, wherein the one or more silanes comprises triethoxy(octyl)silane, 1,8-bistrimethoxy silyloctane, (3-glycidyloxypropyl)methyldiethoxysilane, (3- aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole, (3- triethoxysilyl)propyl succinic anhydride, N-(triethoxysilylpropyl)-O-polyoxyethylene polyurethane, (3-mercaptopropyl)-triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)-propyl]disulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide, triethoxyallyl silane, or any combination thereof.

4. The method of claim 1, wherein the surface-modified silica comprises a surface modification comprising a surfactant, a hydrophobic polymeric film, a silane-containing coupling agent, and an ethoxylated alcohol ether, or any combination thereof.

5. A masterbatch material prepared by the method of claim 1.

6. The masterbatch material of claim 5, wherein the rubber latex comprises a natural rubber latex, an emulsion styrene butadiene rubber (eSBR), or any combination thereof.

7. An uncured rubber composition comprising the masterbatch material of claim 5.

8. A cured rubber composition comprising the uncured rubber composition of claim 7, followed by a curing step.

9. An article comprising the cured rubber composition of claim 8.

10. The article of claim 9, wherein the article comprises a tire.

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