Surface modification of silica in hydrocarbon solvent, masterbatch and rubber composition

Abstract

A method of producing a stabilized silica / hydrocarbon solution includes ultrasonically mixing silica and a silane in a hydrocarbon solvent. The solution may be dried to obtain a surface-modified silica. The solution may be mixed with a polymer cement to produce a silica-rubber (e.g., silica-SSBR) masterbatch product.

Description

Technical Field

[0001] The present invention relates to surface modification of silica in hydrocarbon solvents, masterbatches and rubber compositions. Background Art

[0002] Silica is hydrophilic and therefore does not disperse easily in hydrocarbon solvents. For example, silica is immiscible in hexane by conventional mixing methods.

[0003] It is desirable to develop new methods for producing stable solutions of silica in hydrocarbon solvents (e.g., for use in applications such as obtaining surface-modified silica and producing masterbatches), new methods for producing surface-modified silica, and new methods for producing silica-rubber (e.g., silica-SSBR) masterbatches. Summary of the invention

[0004] An ultrasonic vibration system is used to promote the silanization reaction between silica and silane in a hydrocarbon solvent. The resulting solution is stable.

[0005] The solution can be dried directly to produce surface modified silica (similar to or product). Alternatively, the solution can be mixed with a polymer cement to produce a silica / polymer masterbatch.

[0006] The technology of this process method can be used to incorporate silica into almost any type of rubbery polymer (elastomer). For example, the rubbery polymer can be natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), styrene-isoprene-butadiene rubber (SIBR) or other types of conventional polydiene rubbers.

[0007] In some embodiments, a method for producing a stable solution containing silicon dioxide in a hydrocarbon solvent is disclosed. The method includes ultrasonically mixing silicon dioxide and silane in the hydrocarbon solvent. In some embodiments, the hydrocarbon solvent is an alkane (e.g., hexane or cyclohexane). Ultrasonic mixing can be performed for a time of about 1 to about 40 minutes (e.g., about 10 to about 40 minutes) and / or at room temperature. The silane can be triethoxysilane. In some embodiments, the silane is triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)-triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)-propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide. Also disclosed is a solution made by the method.

[0008] In other embodiments, a method for producing surface-modified silica is disclosed. The method includes ultrasonically mixing silica and silane in a hydrocarbon solvent to form a solution; and drying the solution to obtain surface-modified silica. In some embodiments, the hydrocarbon solvent includes an alkane (e.g., hexane or cyclohexane). The silane may include triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)-triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)-propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide and / or bis[3-(triethoxysilyl)-propyl]tetrasulfide. Surface-modified silica prepared by the method is also disclosed.

[0009] In a further embodiment, a method for preparing a masterbatch is disclosed. The method includes ultrasonically mixing silica and silane in a hydrocarbon solvent to form a solution; mixing the solution and a polymer cement to form a mixture; and drying the mixture to form a masterbatch. The polymer cement may include a rubber selected from natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR) and styrene-isoprene-butadiene rubber (SIBR). In some embodiments, the solvent includes an alkane (e.g., hexane or cyclohexane). In some embodiments, the silane comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyl-diethoxysilane, (3-aminopropyl)-triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)-propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)triethoxysilane, S-(octanol)-mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide. The mixing can be performed for a period of about 30 to about 60 minutes. A masterbatch made by the method is also disclosed.

[0010] In some embodiments, a method for preparing a masterbatch is disclosed. The method includes ultrasonically mixing silica and silane in a hydrocarbon solvent to form a solution; mixing the solution with a polymer cement to form a mixture; and drying the mixture to form a masterbatch.

[0011] The polymer cement may include at least one rubber selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), and styrene-isoprene-butadiene rubber (SIBR). In some embodiments, the hydrocarbon solvent includes an alkane. The hydrocarbon solvent may include hexane or cyclohexane. In some embodiments, the silane includes triethoxysilane. The silane may include triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide. In some embodiments, the solution and the polymer cement are mixed for a period of about 30 to about 60 minutes. The ultrasonic mixing may be performed for a period of about 1 to about 40 minutes. In some embodiments, the ultrasonic mixing is performed at room temperature. Also disclosed is a masterbatch formed by the method.

[0012] In other embodiments, a method for preparing a masterbatch is disclosed. The method includes mixing a solution containing a surface-modified silane in a hydrocarbon solvent with a polymer cement to form a mixture; and drying the mixture to form a masterbatch. The polymer cement may include at least one rubber selected from natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR) and styrene-isoprene-butadiene rubber (SIBR). In some embodiments, the hydrocarbon solvent comprises an alkane. In some embodiments, the hydrocarbon solvent comprises hexane or cyclohexane. The surface-modified silica may be a silane-modified silica. In some embodiments, the silane comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide. The solution and the polymer cement may be mixed for a period of about 30 to about 60 minutes. In some embodiments, the ultrasonic mixing is performed for a period of about 1 to about 40 minutes. The ultrasonic mixing may be performed at room temperature. Also disclosed is a masterbatch formed by the method.

[0013] The present invention discloses the following scheme:

[0014] Scheme 1. A method for preparing a masterbatch, the method comprising:

[0015] ultrasonically mixing silica and silane in a hydrocarbon solvent to form a solution;

[0016] mixing the solution and the polymer cement to form a mixture; and

[0017] The mixture is dried to form a masterbatch.

[0018] Option 2. The method according to Option 1, wherein the polymer cement comprises a rubber selected from the group consisting of:

[0019] Natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR) and styrene-isoprene-butadiene rubber (SIBR).

[0020] Option 3. A method according to Option 1, wherein the hydrocarbon solvent comprises an alkane.

[0021] Option 4. The method according to Option 1, wherein the hydrocarbon solvent comprises hexane or cyclohexane.

[0022] Option 5. The method according to Option 1, wherein the silane comprises triethoxysilane.

[0023] Scheme 6. A method according to Scheme 1, wherein the silane comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)-triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)-propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide.

[0024] Option 7. The method according to Option 1, wherein the solution and the polymer cement are mixed for a period of about 30 to about 60 minutes.

[0025] Option 8. A method according to Option 1, wherein the ultrasonic mixing is performed for a period of about 1 to about 40 minutes.

[0026] Option 9. A method according to Option 1, wherein the ultrasonic mixing is performed at room temperature.

[0027] Scheme 10. A masterbatch formed by the method of Scheme 1.

[0028] Scheme 11. A method for preparing a masterbatch, the method comprising:

[0029] mixing a solution containing a surface-modifying silane in a hydrocarbon solvent with a polymer cement to form a mixture; and

[0030] The mixture is dried to form a masterbatch.

[0031] Embodiment 12. The method according to embodiment 11, wherein the polymer cement comprises a rubber selected from the group consisting of:

[0032] Natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR) and styrene-isoprene-butadiene rubber (SIBR).

[0033] Option 13. A method according to Option 11, wherein the hydrocarbon solvent comprises an alkane.

[0034] Option 14. A method according to Option 11, wherein the hydrocarbon solvent comprises hexane or cyclohexane.

[0035] Option 15. The method according to Option 11, wherein the surface-modified silica is silane-modified silica.

[0036] Scheme 16. A method according to Scheme 15, wherein the silane comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide.

[0037] Embodiment 17. The method according to embodiment 11, wherein the solution and the polymer cement are mixed for a period of about 30 to about 60 minutes.

[0038] Option 18. A method according to Option 11, wherein the ultrasonic mixing is performed for a period of about 1 to about 40 minutes.

[0039] Option 19. A method according to Option 11, wherein the ultrasonic mixing is carried out at room temperature.

[0040] Scheme 20. A masterbatch formed by the method described in Scheme 11.

[0041] These and other non-limiting aspects and / or objects of the present disclosure are more particularly described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The following is a brief description of the drawings which are presented for the purpose of illustrating exemplary embodiments disclosed herein and not for the purpose of limiting the same.

[0043] Figure 1 is a flow chart illustrating a method of producing a stable silica / hydrocarbon solution according to some embodiments of the present disclosure.

[0044] Figure 2 is a flow chart illustrating a method of producing surface-modified silica according to some embodiments of the present disclosure.

[0045] Figure 3 is a flow chart illustrating a method of producing a masterbatch according to some embodiments of the present disclosure.

[0046] Figure 4is a photograph of the mixture prepared in Example 1.

[0047] Figure 5 is a photograph of the mixture prepared in Example 2.

[0048] Figure 6 is a photograph of the gel-like mixture prepared in Example 3.

[0049] Figure 7 is a photograph of the solution prepared in Example 4.

[0050] Figure 8 is a photograph of the solution prepared in Example 5.

[0051] Fig. 9 is a photograph of the emulsion solution prepared in Example 6.

[0052] Fig.10 is a photograph of the phase separation product prepared in Example 7.

[0053] Fig.11 is a photograph of the stable emulsion solution prepared in Example 8.

[0054] Fig.12 is a photograph of the emulsion solution prepared in Example 9.

[0055] Fig.13 is a photograph of the emulsion solution prepared in Example 10.

[0056] Fig.14 is a photograph of the emulsion solution prepared in Example 11.

[0057] Fig.15 is a photograph of the emulsion solution prepared in Example 12.

[0058] Fig.16 is a photograph of the milky stable solution prepared in Example 13.

[0059] Fig.17 is a photograph of the product prepared in Example 16.

[0060] Fig.18 is a photograph of the product prepared in Example 17.

[0061] Fig.19 is a photograph of the product prepared in Example 18.

[0062] Fig. 20 is a photograph of the product prepared in Example 19. DETAILED DESCRIPTION

[0063] The present disclosure may be more readily understood by reference to the following detailed description and accompanying drawings of contemplated embodiments contained therein.In the following specification and in the claims that follow, reference will be made to a number of terms which shall be defined to have the following meanings.

[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as are commonly understood by those of ordinary skill in the art. In the event of a conflict, this document (including definitions) shall prevail. Methods and materials are described below, although similar or equivalent methods and materials may be used in the practice or testing of the present disclosure. All publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference in their entirety. The materials, methods, and products disclosed herein are exemplary only and are not intended to be limiting.

[0065] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0066] The term "comprising" as used in the specification and claims may include the embodiments of "consisting of" and "consisting essentially of." As used herein, the terms "comprising," "including," "having," "having," "may," "containing," and variations thereof are intended to be open transition phrases that require the presence of specified ingredients / steps and allow for the presence of other ingredients / steps. However, such descriptions should be interpreted as also describing compositions, mixtures, or methods as "consisting of" and "consisting essentially of" the listed ingredients / steps, which only allow for the presence of the specified ingredients / steps, and any impurities that may result therefrom, and exclude other ingredients / steps.

[0067] Unless otherwise indicated, the numerical values ​​in the specification should be understood to include the same value when reduced to the same number of significant figures and values ​​that differ from the specified value by less than the experimental error of ordinary measurement techniques used to determine the particular value.

[0068] All ranges disclosed herein are inclusive of the recited endpoints and are independently combinable (e.g., the range "2 to 10" includes the endpoints, 2 and 10, and all intermediate values). The endpoints of the ranges and any values ​​disclosed herein are not limited to the exact ranges or values; they are imprecise enough to include values ​​approximating these ranges and / or values.

[0069] As used herein, approximations can be used to modify any quantitative representation that may vary without causing a change in the basic function to which it relates. Therefore, values ​​modified by terms such as "approximately" and "substantially" are not limited to the specified exact values ​​in some cases. The modifier "approximately" should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. For example, the phrase "about 2 to about 4" also discloses a range of "2 to 4". The term "approximately" can refer to plus or minus 10% of the numerical value shown. For example, "about 10%" can refer to a range of 9% to 11%, and "about 1" can refer to 0.9-1.1.

[0070] For the enumeration of numerical ranges herein, each intermediate number with the same precision is explicitly considered. For example, for the range of 6-9, in addition to 6 and 9, the numbers 7 and 8 are also considered, and for the range of 6.0-7.0, the numbers 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9 and 7.0 are explicitly considered.

[0071] The present disclosure relates to methods of producing stable silica / hydrocarbon solutions, methods of producing surface-modified silica, and methods of producing masterbatches.

[0072] Figure 1 is a flow chart illustrating a method 100 of producing a stable silica / hydrocarbon solution according to some embodiments of the present disclosure.

[0073] The method 100 includes providing silica, silane, and a hydrocarbon solvent 110; and ultrasonically mixing to form a stable solution 120. The ultrasonically mixing 120 can promote a silanization reaction between the silica and the silane in the hydrocarbon solvent.

[0074] The silica may include fumed silica and / or precipitated silica.

[0075] The silica may have a BET (Brunauer-Emmett-Teller) surface area as measured using nitrogen. In some embodiments, the BET surface area may be from about 40 to about 600 square meters per gram, or from about 80 to about 300 square meters per gram. The BET method for measuring surface area may be described in, for example, Journal of the American Chemical Society, Vol. 60, and ASTM D3037.

[0076] The silica may also be characterized as having a dibutyl phthalate (DBP) absorption value of about 100 to about 400, including about 150 to about 300.

[0077] The silica may be expected to have an average ultimate particle size, for example, between 0.01 and 0.05 microns as determined by electron microscopy, although the silica particles may be smaller or may be larger in size.

[0078] Various commercially available silicas may be used, such as, by way of example only and not limitation, silicas available from PPG Industries under the Hi-Sil trademark and designations 210, 243, etc.; for example, Zeosil 1165MP TM and Zeosil 165GR TM Silica from Solvay; For example, silicas from Evonik under the names VN2 and VN3; Chemically treated (pre-hydrophobized) precipitated silicas, for example Agilon from PPG TM 400; silicas available from Rhodia, for example, under the names Z1165MP and Z165GR, and silicas available from Degussa AG, for example, under the names VN2 and VN3, and the like.

[0079] The silane may include an alkoxyorganomercaptosilane, an alkylsilane, a bis-3 (trialkoxysilylalkyl) polysulfide and / or an alkoxysilane.

[0080] The alkoxysilane may be ethoxysilane or methoxysilane.

[0081] Non-limiting examples of organomercaptosilanes include S-(octanol)mercaptopropyltriethoxysilane, 3-mercaptopropyltriethoxysilane, triethoxymercaptopropylsilane, trimethoxymercaptopropylsilane, methyldimethoxymercaptopropylsilane, methyldiethoxymercaptopropylsilane, dimethylmethoxymercaptopropylsilane, triethoxymercaptoethylsilane, and tripropoxymercaptopropylsilane.

[0082] In some embodiments, the silane is selected from S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)propyl]tetrasulfide, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-phenylenediyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyl trimethoxysilane, N-2-(aminoethyl)-3-aminopropyl methyl dimethoxysilane, N-2-(aminoethyl)-3-aminopropyl trimethoxysilane, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3-triethoxysilyl-N-(1,3 dimethyl-butylene) propylamine, N-phenyl-3-aminopropyl trimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyl trimethoxysilane hydrochloride, 3-ureapropyl trialkoxysilane, 3-isocyanate propyl triethoxysilane, tris-(trimethoxysilylpropyl) isocyanurate, 3-mercaptopropyl methyl dimethoxysilane and 3-mercaptopropyl trimethoxysilane. Mixtures of two or more silanes may also be used.

[0083] The hydrocarbon solvent may include one or more of aromatic compounds, paraffinic compounds, and / or cycloparaffinic compounds.

[0084] In some embodiments, the hydrocarbon solvent contains from 4 to 10 carbon atoms.

[0085] The weight ratio of silica to silane may be from about 6 to about 33.3.

[0086] The ratio of hydrocarbon solvent (volume) to silica (weight) may be from about 4 to about 10 ml / g.

[0087] The ratio of hydrocarbon solvent (volume) to silane (weight) may be from about 40 to about 200 ml / g.

[0088] Non-limiting examples of suitable hydrocarbon solvents include butane, pentane, isooctane, cyclohexane, n-hexane, benzene, toluene, xylene, ethylbenzene and diethylbenzene. Mixtures of two or more hydrocarbon solvents may also be used.

[0089] Non-limiting examples of ultrasonic mixers include 500- and / or 750-watt ultrasonic liquid processors (e.g., from Cole-Parmer-anAntylia Scientific). The ultrasonic probe may have a diameter of about 5 to about 50 mm, including about 10 to about 30 mm. A standard ultrasonic probe with a diameter of 12.7 mm may be suitable for ultrasonic processing of a volume of 250 ml, or a probe with a diameter of 25.4 mm may be suitable for ultrasonic processing of a volume of up to 1000 ml.

[0090] In a non-limiting example of a method for preparing a silica / silane / hexane solution, 15 to 25 grams of silica and 0.75 to 2.5 grams of silane (5 to 10 parts per hundred filler (phf), e.g., 8 phf) are added to a 300 ml glass bottle equipped with a magnetic stirrer plus a magnetic bar, followed by 100 to 150 ml of hexane or cyclohexane. The mixture is sonicated at room temperature for 10 to 40 minutes at 44% amplitude and magnetic stirring.

[0091] In a non-limiting example of a method for preparing surface-modified silica, 15 to 25 grams of silica and 0.75 to 2.5 grams of silane (5 to 10 phf) are added to a 300 ml glass bottle equipped with a magnetic stirrer plus a magnetic bar, followed by 100 to 150 ml of hexane or cyclohexane. The mixture is sonicated at room temperature for 10 to 40 minutes at 44% amplitude and magnetic stirring. The solvent is removed by rotary evaporation and then air-dried overnight in a fume hood. Surface-modified silica is obtained.

[0092] In a non-limiting example of a method for preparing a silica-SSBR masterbatch material, 15 to 25 grams of silica and 0.75 to 2.5 grams of silane (5 to 10 phf) are added to a 300 ml glass bottle equipped with a magnetic stirrer plus a magnetic bar, followed by 100 to 150 ml of hexane or cyclohexane. The mixture is sonicated at room temperature for 10 to 40 minutes at 50% amplitude and magnetic stirring.

[0093] The silica / silane / hexane solution is mixed with the SSBR polymer cement (by controlling the silica / SSBR ratio for the desired silica loading) and shaken at high speed for 30 to 60 minutes in a benchtop reciprocating shaker or mixed in a reactor with stirring (eg, 200 to 500 rpm).

[0094] The silica-SSBR-masterbatch material was obtained after direct drum drying of the above mixture, or coagulation with isopropanol and the solid product was air dried overnight or steam stripped & dried in a fume hood.

[0095] Figure 2is a flow chart illustrating a method 201 of producing surface-modified silica according to some embodiments of the present disclosure. The method 201 includes providing silica, silane, and a hydrocarbon solvent 210; ultrasonically mixing to form a stable solution 220; and drying to form surface-modified silica 240.

[0096] The providing 210 and ultrasonic mixing 220 may be Figure 1 The corresponding steps 110 and 120 in are similar or identical.

[0097] Figure 3 is a flow chart illustrating a method 302 of producing a masterbatch according to some embodiments of the present disclosure. The method 302 includes providing silica, silane, and a hydrocarbon solvent 310; ultrasonically mixing to form a stable solution 320; mixing the solution with a polymer cement 330; and drying to form surface-modified silica 340.

[0098] The providing 310 and ultrasonic mixing 320 may be Figure 1 The corresponding steps 110 and 120 in are similar or identical.

[0099] The solution may be liquid / liquid mixed 330 with a polymer cement in the same solvent to achieve dispersion of the silica in the rubber phase.

[0100] The polymer cement may contain a rubber (e.g., a diene-containing rubber). Non-limiting examples include natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), and styrene-isoprene-butadiene rubber (SIBR).

[0101] The masterbatch may be compounded into the rubber composition.

[0102] The rubber composition may optionally include one or more rubbers or elastomers containing ethylenic unsaturation in addition to the masterbatch. The additional rubber / elastomer may be the same or different from the rubber / elastomer of the masterbatch. The phrase "rubber or elastomer containing ethylenic unsaturation" or "diene-based elastomer" is intended to include natural rubber and its various original and regenerated forms, as well as various synthetic rubbers. In the specification, unless otherwise specified, the terms "rubber" and "elastomer" are used interchangeably. The terms "rubber composition", "compound rubber" and "rubber compound" are used interchangeably to refer to rubbers that have been blended or mixed with various ingredients and materials, and such terms are well known to technicians in the field of rubber mixing or rubber compounding. Representative synthetic polymers are butadiene and its homologues and derivatives, such as homopolymerization products of methylbutadiene, dimethylbutadiene and pentadiene, and copolymers, such as copolymers formed by butadiene or its homologues or derivatives and other unsaturated monomers. Other unsaturated monomers include acetylenes such as vinyl acetylene; olefins such as isobutylene, which copolymerizes with isoprene to form butyl rubber; vinyl compounds such as acrylic acid, acrylonitrile (which polymerizes with butadiene to form NBR), methacrylic acid, and styrene (the latter compound polymerizes with butadiene to form SBR), as well as vinyl esters and various unsaturated aldehydes, ketones, and ethers, such as acrolein, methyl isopropenyl ketone, and vinyl ethyl ether. Specific examples of synthetic rubbers include chloroprene rubber (polychloroprene), polybutadiene (including cis-1,4-polybutadiene), polyisoprene (including cis-1,4-polyisoprene), butyl rubber, halogenated butyl rubber such as chlorobutyl rubber or bromobutyl rubber, styrene / isoprene / butadiene rubber, copolymers of 1,3-butadiene or isoprene with monomers such as styrene, acrylonitrile and methyl methacrylate, and ethylene / propylene terpolymers, also known as ethylene / propylene / diene monomers (EPDM), particularly ethylene / propylene / dicyclopentadiene terpolymers. Additional examples of useful rubbers include alkoxy-silyl end-functionalized solution polymerized polymers (SBR, PBR, IBR and SIBR), silicon-coupled and tin-coupled star-branched polymers. Preferred rubbers or elastomers are polyisoprene (natural or synthetic), polybutadiene and SBR.

[0103] In some embodiments, the at least one additional rubber is preferably at least two diene-based rubbers. For example, a combination of two or more rubbers is preferred, such as cis-1,4-polyisoprene rubber (natural or synthetic, but natural is preferred), 3,4-polyisoprene rubber, styrene / isoprene / butadiene rubber, emulsion and solution polymerization derived styrene / butadiene rubber, cis-1,4-polybutadiene rubber, and butadiene / acrylonitrile copolymers prepared by emulsion polymerization.

[0104] In some embodiments, an emulsion polymerization derived styrene / butadiene (E-SBR) having a relatively conventional styrene content of about 20 to about 28% bound styrene may be used, or for some applications, an E-SBR having a moderate to relatively high bound styrene content, i.e., about 30 to about 45% bound styrene content.

[0105] E-SBR prepared by emulsion polymerization refers to copolymerization of styrene and 1,3-butadiene as an aqueous emulsion. This is well known to those skilled in the art. The bound styrene content may vary, for example, from about 5% to about 50%. In one aspect, the E-SBR may also contain acrylonitrile as E-SBAR to form a terpolymer rubber, the amount of bound acrylonitrile in the terpolymer being, for example, from about 2 to about 30 weight percent.

[0106] Emulsion polymerization prepared styrene / butadiene / acrylonitrile copolymer rubbers containing from about 2 to about 40 weight percent bound acrylonitrile in the copolymer are also contemplated as diene based rubbers.

[0107] Solution polymerization prepared SBR (S-SBR) generally has a bound styrene content of about 5 to about 50%, preferably about 9 to about 36%. S-SBR can be conveniently prepared, for example, by organolithium catalysis in the presence of an organic hydrocarbon solvent.

[0108] In one embodiment, cis 1,4-polybutadiene rubber (BR) may be used. Such BR may be prepared, for example, by organic solution polymerization of 1,3-butadiene. The BR may conveniently be characterized, for example, as having a cis 1,4-content of at least 90%.

[0109] Cis 1,4-polyisoprene and cis 1,4-polyisoprene natural rubber are well known to those skilled in the rubber art.

[0110] As used herein and according to conventional practice, the term "phr" means "parts by weight of the respective material per 100 parts by weight of rubber or elastomer."

[0111] The rubber composition can also include up to 70phr of processing oil. Processing oil can be included in the rubber composition as a filler oil commonly used to fill elastomers. Processing oil can also be included in the rubber composition by directly adding the oil during rubber compounding. The processing oil used can include the filler oil present in the elastomer and the process oil added during compounding. Suitable process oils include various oils known in the art, including aromatic oils, paraffinic oils, naphthenic oils, vegetable oils and low PCA oils, such as MES, TDAE, SRAE and heavy naphthenic oils. Suitable low PCA oils include those with a polycyclic aromatic hydrocarbon content of less than 3% by weight as measured by the IP346 method. The procedure of the IP346 method can be found in Standard Methods for Analysis & Testing of Petroleum and Related Products and British Standard 2000 Parts, 2003, the 62nd edition, published by the Institute of Petroleum, United Kingdom.

[0112] The rubber compound may include about 10 to about 150 phr of silica. In another embodiment, 20 to 80 phr of silica may be used. In some embodiments, all of the silica in the rubber compound comes from a masterbatch. In other embodiments, additional silica is added during the compounding process.

[0113] Common siliceous pigments that can be used in the rubber compound include conventional pyrogenic and precipitated siliceous pigments (silicon dioxide). In one embodiment, precipitated silica is used. Conventional siliceous pigments used are precipitated silicas, such as those obtained by acidification of soluble silicates, such as sodium silicate.

[0114] Such conventional silica can be characterized, for example, by having a BET (Brunauer-Emmett-Teller) surface area as measured using nitrogen. In one embodiment, the BET surface area can be from about 40 to about 600 square meters per gram. In another embodiment, the BET surface area can be from about 80 to about 300 square meters per gram. The BET method for measuring surface area is described in Journal of the American Chemical Society, Vol. 60, p. 304 (1930).

[0115] Conventional silicas may also be characterized as having a dibutyl phthalate (DBP) absorption value of about 100 to about 400, or about 150 to about 300.

[0116] Conventional silica might be expected to have an average ultimate particle size, for example, between 0.01 and 0.05 microns as determined by electron microscopy, although the silica particles might be smaller or larger in size.

[0117] Various commercially available silicas may be used, such as, by way of example only and not limitation, silicas available from PPG Industries under the Hi-Sil trademark and designations 210, 243, etc.; silicas available from Rhodia under the designations Z1165MP and Z165GR, and silicas available from Degussa AG under the designations VN2 and VN3, etc., etc.

[0118] Can use common carbon black as conventional filler with the amount of 10 to 150phr.In another embodiment, can use 20 to 80phr carbon black.Representative example of such carbon black comprises 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 iodine absorption of 9 to 145g / kg and 34 to 150cm 3 / 100g of DBP value.

[0119] Other fillers may be used in the rubber composition, including, but not limited to, particulate fillers, including ultra-high molecular weight polyethylene (UHMWPE), cross-linked particulate polymer gels, including but not limited to those disclosed in U.S. Pat. Nos. 6,242,534; 6,207,757; 6,133,364; 6,372,857; 5,395,891; or 6,127,488, and plasticized starch composite fillers, including but not limited to those disclosed in U.S. Pat. No. 5,672,639. The patents mentioned in the previous sentence are incorporated herein by reference in their entirety. Such other fillers may be used in an amount of 1 to 30 phr.

[0120] In some embodiments, the rubber composition may contain a conventional sulfur-containing organosilicon compound. In one embodiment, the sulfur-containing organosilicon compound is 3,3'-bis(trimethoxy or triethoxysilylpropyl) polysulfide. In one embodiment, the sulfur-containing organosilicon compound is 3,3'-bis(triethoxysilylpropyl) disulfide and / or 3,3'-bis(triethoxysilylpropyl) tetrasulfide.

[0121] In some embodiments, suitable sulfur-containing organosilicon compounds include compounds disclosed in U.S. Pat. No. 6,608,125. In one embodiment, the sulfur-containing organosilicon compound includes 3-(octanoylthio)-1-propyltriethoxysilane, CH3(CH2)6C(═O)—S—CH2CH2CH2Si(OCH2CH3)3, which can be used as NXT TM Purchased from Momentive Performance Materials.

[0122] In another embodiment, suitable sulfur-containing organosilicon compounds include those disclosed in US Patent Publication No. 2003 / 0130535, which is incorporated herein by reference in its entirety. In one embodiment, the sulfur-containing organosilicon compound is Si-363 from Degussa.

[0123] The amount of sulfur-containing organosilicon compound in the rubber composition varies with the content of other additives used. Generally speaking, the amount of the compound is 0.5 to 20 phr. In one embodiment, the amount is 1 to 10 phr.

[0124] It is readily understood by those skilled in the art that the rubber composition is compounded by methods known in the rubber compounding field, such as various sulfur-vulcanizable component rubbers and various commonly used additive materials, such as sulfur-donating bodies, vulcanizing aids (such as activators and delay agents) and processing additives, such as oil, resin (including tackifying resins) and plasticizers, fillers, pigments, fatty acids, zinc oxide, waxes, antioxidants and antiozonants and peptizing agents are mixed. As known to those skilled in the art, according to the intended use of sulfur-vulcanizable and sulfur-vulcanized materials (rubbers), the above-mentioned additives are selected and usually used in conventional amounts. Representative examples of sulfur-donating bodies include elemental sulfur (free sulfur), disulfide amines, polymerized polysulfides and sulfur olefin adducts. In one embodiment, the sulfur vulcanizing agent is elemental sulfur. The sulfur vulcanizing agent can be used in an amount of 0.5 to 8phr, or in the range of 1.5 to 6phr. If a tackifying resin is used, its typical amount includes, for example, 0.5phr to 10phr, usually 1phr to 5phr. If a processing aid is used, a typical amount thereof comprises about 0.5 to about 10 phr, usually about 1 to about 5 phr. A typical amount of a processing aid comprises about 1 to about 50 phr. A typical amount of an antioxidant comprises about 1 to about 5 phr. Representative antioxidants can be, for example, diphenyl-p-phenylenediamine, etc., such as those disclosed in The Vanderbilt Rubber Handbook (1978), pages 344 to 346. A typical amount of an antiozonant comprises about 1 to 5 phr. If a fatty acid (which may include stearic acid) is used, a typical amount thereof comprises about 0.5 to about 3 phr. A typical amount of zinc oxide comprises about 2 to about 5 phr. A typical amount of a wax comprises about 1 to about 5 phr. Microcrystalline wax is generally used. A typical amount of a peptizing agent comprises about 0.1 to about 1 phr. Typical peptizing agents can be, for example, pentachlorothiophenol and dibenzamidodiphenyl disulfide.

[0125] Use accelerator to control the time and / or temperature required for vulcanization and improve the properties of 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 of about 0.5 to about 4 or about 0.8 to about 1.5 phr. In another embodiment, a combination of a primary accelerator and an auxiliary accelerator can be used, and the auxiliary accelerator is used in a relatively small amount, such as about 0.05 to about 3 phr, to activate and improve the properties of the vulcanized rubber. The combination of these accelerators may be expected to produce a synergistic effect on the final properties and slightly better than the effect produced by using any accelerator alone. In addition, an after-effect accelerator that is not affected by normal processing temperature but produces satisfactory vulcanization at ordinary vulcanization temperatures can be used. Vulcanization delay agents may also be used. Available suitable types of accelerators include amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamates and xanthates. In one embodiment, the primary accelerator is a sulfenamide. If an auxiliary accelerator is used, the auxiliary accelerator can be a guanidine, dithiocarbamate or a thiuram compound.

[0126] The mixing of the rubber composition can be achieved by methods known to those skilled in the art of rubber mixing. For example, the ingredients are usually mixed in at least two stages, i.e., at least one non-productive stage and then a productive mixing stage. The final curing agent (curatives) including a sulfur vulcanizing agent is usually mixed in the last stage (which is conventionally referred to as a "productive" mixing stage, wherein the mixing is usually carried out at a temperature lower than the mixing temperature of the previous non-productive mixing stage or at a final temperature). The terms "non-productive" and "productive" mixing stages are well known to those skilled in the art of rubber mixing. The rubber composition can be subjected to a thermomechanical mixing step. The thermomechanical mixing step is usually included in a time in which mechanical processing in a mixer or extruder is suitable for producing a rubber temperature of 140°C to 190°C. The appropriate duration of the thermomechanical processing varies with the operating conditions and the volume and properties of the components. For example, the thermomechanical processing can be 1 to 20 minutes.

[0127] The rubber composition can be incorporated into various rubber components of a tire. For example, the rubber component can be a tread (including a tread cap and a tread base), a sidewall, an apex, a chafer, a sidewall insert, a wirecoat, or an innerliner. In one embodiment, the component is a tread.

[0128] The pneumatic tire can be a racing tire, a car tire, an aircraft tire, an agricultural tire, a bulldozer tire, an off-road tire, a truck tire, etc. In one embodiment, the tire is a car or truck tire. The tire can also be a radial tire or a bias tire.

[0129] The rubber composition may also be used in other products including, but not limited to, non-pneumatic tires, belts, hoses, shoes, air springs, engine mounts, and the like.

[0130] The vulcanization of the pneumatic tire can be carried out at conventional temperatures of about 100° C. to 200° C. In one embodiment, the vulcanization is carried out at a temperature of about 110° C. to 180° C. Any conventional vulcanization method can be used, such as heating in a press or mold, heating with superheated steam or hot air. Such tires can be built, shaped, molded and vulcanized by various methods known and obvious to those skilled in the art.

[0131] The following examples are provided to illustrate the apparatus and methods of the present disclosure. These examples are exemplary only and are not intended to limit the present disclosure to the materials, conditions or process parameters set forth therein.

[0132] Example

[0133] Example 1.

[0134] 20 g of silica and 2 g of S-(octanol)mercaptopropyltriethoxysilane were added to 100 g of hexane. The mixture was sonicated in a water bath for 1 hour. The resulting two-phase mixture was shown in Figure 4 in the photo.

[0135] Example 2.

[0136] 20 g of silica and 2 g of S-(octanol)mercaptopropyltriethoxysilane were added to 100 g of hexane. The mixture was stirred in a 65°C water bath for 1 hour. Figure 5 As shown in the photograph, it separated into two phases.

[0137] Example 3.

[0138] 20 g of silica was added to 100 g of hexane. The mixture was ultrasonically vibrated (Ultrasonic Liquid Processor from Sonics & Materials Inc.) for 15 minutes. A suspension was formed and gelled after 24 hours. The gel-like mixture was shown in Figure 6 in the photo.

[0139] Example 4.

[0140] 20 g of silica and 2 g of bis[3-(triethoxysilyl)propyl]tetrasulfide were added to 100 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was stable for at least one week and showed Figure 7 GC-MS has detected the silylation product of ethanol (C2H5OH).

[0141] Example 5.

[0142] 20 g of silica and 2 g of S-(octanol)mercaptopropyltriethoxysilane were added to 100 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was stable for at least one week and showed Figure 8 in the photo.

[0143] Example 6.

[0144] 20 g of silica and 2 g of n-octyltriethoxysilane were added to 100 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was stable for at least one week and showed Fig. 9 in the photo.

[0145] Example 7.

[0146] 10.8 g of silicon dioxide (SiO2) and 1 g of S-(octanol)mercaptopropyltriethoxysilane were added to 121 g of SSBR polymer cement (SBR = 16.6 g; 13.73% solids; polymer / SiO2 = 100 / 65). The mixture was ultrasonically vibrated for 15 minutes and shaken for another 30 minutes. Fig.10 As shown in the photo, the silica phase separated from the polymer cement.

[0147] Example 8.

[0148] 85 g of the silica / hexane solution from Example 5 (containing 13.9 g of SiO2) was mixed with 140 g of SSBR polymer cement (13.73% solids in hexane) (SBR / SiO2=100 / 70) and shaken at room temperature for 10 minutes. A stable emulsion solution was formed and showed Fig.11 in the photo.

[0149] Example 9.

[0150] 25 g of silica (BET surface area: 160 m 2 / g) and 2 g of n-octyltriethoxysilane were added to 120 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was shown in Fig.12 in the photo.

[0151] Example 10.

[0152] 25 g of silica (BET surface area: 160 m 2 / g) and 2 g of S-(octanol) mercaptopropyl-triethoxysilane were added to 120 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was shown in Fig.13 in the photo.

[0153] Example 11.

[0154] 25 g of silica (BET surface area: 160 m 2 / g) and 2 g of bis[3-(triethoxysilyl)-propyl]tetrasulfide were added to 120 g of hexane. The mixture was ultrasonically vibrated for 15 minutes. A milky solution was formed. The solution was shown in Fig.14 in the photo.

[0155] Example 12

[0156] 25 g of silica (BET surface area: 160 m 2 / g) and 2 g of bis[3-(triethoxysilyl)propyl]-disulfide (CAS: 56706-10-6; d = 1.025) were added to 120 g of hexane and sonicated for 15 minutes. A milky stable solution was formed and showed Fig.15 in the photo.

[0157] Example 13

[0158] 20 g of silica (BET surface area: 210 m 2 / g) and 2 g of bis[3-(triethoxysilyl)propyl]-disulfide (CAS: 56706-10-6; d = 1.025) were added to 110 g of hexane and sonicated for 15 minutes. A milky stable solution was formed and showed Fig.16 in the photo.

[0159] Examples 14 and 15

[0160] Non-functionalized SSBR and vinylsilane functional SSBR were synthesized in Examples 14 and 15, respectively. Details about these polymers are summarized in the following table:

[0161] Polymer ID Non-Fn-SSBR (Example 14) Fn-SSBR (Example 15) Glue amount 2 Gallon 2 Gallon BaseMooney 36.1 48.4 %solid 14.7 14.7 %Styrene 20.5 20.1 % Vinyl 47.7 49.3 Tg(℃) -22.6 -22.9

[0162] Example 16

[0163] 250 g of silica / S-(octanol)mercaptopropyltriethoxysilane (8 phf) / hexane solution [containing 45 g of silica (BET surface area: 160 m 2 / g)] was mixed with 440 g of non-functional SSBR polymer cement (14.7% solids in hexane) (SBR / SiO2=100 / 70) and shaken at room temperature for 30 minutes. The mixture was directly drum dried or coagulated with isopropanol and the solid product was air-dried in a fume hood overnight.

[0164] The product is labeled as non-Fn-SBR / silane / silica (100 / 8phf / 70) and is shown in Fig.17in the photo.

[0165] Embodiment 17

[0166] 250 g of silica / S-(octanol)mercaptopropyltriethoxysilane (8 phf) / hexane solution [containing 45 g of silica (BET surface area: 160 m 2 / g)] was mixed with 440 g of silane functional SSBR polymer cement (14.7% solids in hexane) (SBR / SiO2=100 / 70) and shaken at room temperature for 30 minutes. The mixture was directly drum dried or coagulated with isopropanol and the solid product was air-dried in a fume hood overnight.

[0167] The product is labeled FN-SBR / Silane / Silica (100 / 8phf / 70) and is shown in Fig.18 in the photo.

[0168] Embodiment 18

[0169] 255 g of silica / S-(octanol)mercaptopropyltriethoxysilane (10 phf) / hexane solution (containing 45 g of silica (BET surface area: 160 m 2 / g)) was mixed with 383 g of silane functional SSBR polymer cement (14.7% solids in hexane) (SBR / SiO2=100 / 80) and shaken at room temperature for 30 minutes. The mixture was directly drum dried or coagulated with isopropanol and the solid product was air-dried overnight in a fume hood.

[0170] The product is labeled FN-SBR / Silane / Silica (100 / 10phf / 80) and is shown in Fig.19 in the photo.

[0171] Example 19.

[0172] 255 g of silica / S-(octanol)mercaptopropyltriethoxysilane (10 phf) / hexane solution (containing 45 g of silica (BET surface area: 160 m 2 / g)) was mixed with 307 g of silane functional SSBR polymer cement (14.7% solids in hexane) (SBR / SiO2=100 / 100) and shaken at room temperature for 30 minutes. The mixture was directly drum dried or coagulated with isopropanol and the solid product was air-dried overnight in a fume hood.

[0173] The product is labeled FN-SBR / Silane / Silica (100 / 10phf / 100) and is shown in Fig. 20 in the photo.

[0174] This written specification uses examples to disclose the present disclosure, including the best mode, and to enable any person skilled in the art to make and use the present disclosure. Other examples that occur to those skilled in the art are intended to be within the scope of the present disclosure if they have structural elements that are not different from the same concept or if they include equivalent structural elements with insubstantial differences. It is to be recognized that variations of the above-disclosed and other features and functions, or alternatives thereto, may be combined into many other different systems or applications. Those skilled in the art may subsequently make various currently unforeseen or unexpected substitutions, modifications, changes or improvements, which are also intended to be covered by the following claims.

Claims

1. A method for preparing a masterbatch, the method comprising: ultrasonically mixing silica and silane in a hydrocarbon solvent to form a solution; mixing the solution and the polymer cement to form a mixture; and The mixture is dried to form a masterbatch.

2. The method of claim 1, wherein the polymer cement comprises a rubber selected from the group consisting of: Natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, isoprene-butadiene rubber (IBR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR) and styrene-isoprene-butadiene rubber (SIBR).

3. The method of claim 1, wherein the hydrocarbon solvent comprises an alkane.

4. The method of claim 1, wherein the hydrocarbon solvent comprises hexane or cyclohexane. The method of claim 1 , wherein the silane comprises triethoxysilane.

6. The method of claim 1, wherein the silane comprises triethoxy(octyl)silane, 1,8-bistriethoxysilyloctane, (3-glycidoxypropyl)methyldiethoxysilane, (3-aminopropyl)triethoxysilane, N-(3-triethoxysilylpropyl)4,5-dihydroimidazole, (3-triethoxysilyl)propylsuccinic anhydride, N-(triethoxysilylpropyl)-O-polyethylene oxide amine, (3-mercaptopropyl)-triethoxysilane, S-(octanol)mercaptopropyltriethoxysilane, bis[3-(triethoxysilyl)-propyl]disulfide and / or bis[3-(triethoxysilyl)propyl]tetrasulfide.

7. The method of claim 1, wherein the solution and the polymer cement are mixed for a period of about 30 to about 60 minutes.

8. The method of claim 1, wherein the ultrasonic mixing is performed for a period of about 1 to about 40 minutes.

9. The method of claim 1, wherein the ultrasonic mixing is performed at room temperature.

10. A masterbatch formed by the method of claim 1.

Images