Solid carbon black materials and their preparation, and compositions and articles containing same

Abstract

The present disclosure provides a solid carbon black material comprising an oxidized carbon black having a pH greater than 7, a composition comprising such a solid carbon black material and a polymer component, and articles made therefrom. The present disclosure also relates to a method for producing the solid carbon black material. The solid carbon black material is particularly useful for obtaining rubber compounds with low hysteresis, for example, for the production of energy-saving tires with enhanced cure rates compared to the use of conventional oxidized carbon black.

Description

[Technical Field]

[0001] This disclosure relates to solid carbon black materials, including carbon black oxide, more specifically basic carbon black oxide, related polymer compositions, particularly vulcanizable rubber compositions, and articles manufactured therefrom, as well as methods for preparing each. Solid carbon black materials are particularly useful for obtaining rubber products, such as those for tire applications, with improved curing speed and reduced hysteresis compared to the use of conventional carbon black oxide. [Background technology]

[0002] Polymer compositions, such as rubber compositions, are widely used to manufacture numerous industrial products, including transmissions and conveyor belts, tires, and footwear. Carbon black is included in many polymer compositions, for example, to modify their color, mechanical, electrical, and / or processing properties. Carbon black is commonly added to rubber compositions used to manufacture tires or their components to impart electrical dissipation to the insulating matrix. At the same time, carbon black additives affect mechanical and elastic properties such as stiffness, wear resistance, and hysteresis, which greatly influence the performance of the resulting tire, for example, in terms of its rolling resistance and durability. Here, carbon black tends to form a network structure in the matrix through strong filler-filler interactions, which are the main source of heat accumulation in the rubber components. Due to regulatory requirements and increasing environmental burdens, there is a growing demand for energy-saving tires with low rolling resistance. At the same time, other performance parameters such as grip, traction, and durability must not be negatively affected. This often represents conflicting requirements.

[0003] One option for reducing the energy lost in the form of heat during deformation of rubber materials, which is reflected by lower values ​​of hysteresis, is to reduce the filler-filler interaction by increasing the interaction between the carbon black filler and the rubber matrix. Hysteresis can also be reduced by decreasing the amount of carbon black loaded and / or increasing the particle size of the carbon black. However, this may simultaneously degrade electrical dissipation and / or mechanical properties such as abrasion resistance, fracture resistance or chipping resistance.

[0004] Alternatively, developments are underway to chemically modify rubber materials and / or carbon black fillers to enhance the filler-rubber interaction.

[0005] For example, U.S. Patent No. 5,248,722 describes an elastomer composition with reduced rolling resistance in tire tread applications by utilizing a terminally functionalized polymer in combination with acid-functionalized oxidized carbon black. However, terminally functionalized polymers are not readily available and require specialized processes to be prepared by reacting a polymer prepared by polymerization of at least one diene monomer and optionally one or more vinyl-substituted aromatic monomers with a tin or nitrogen-containing compound.

[0006] According to International Publication No. 2011 / 028337, using surface-treated carbon black in combination with a functionalized SBR polymer functionalized with oxygen-containing groups such as carboxylic acids or hydroxyl groups along the chain enhances carbon black-elastomer interactions, resulting in reduced hysteresis and benefits in wet traction compared to the use of conventional carbon black-containing compounds. Surface treatment of carbon black can include oxidation of carbon black followed by treatment with a base such as an amine. Surface-treated carbon black remains acidic, exhibiting a pH < 7.

[0007] The use of acid-functionalized carbon black significantly inhibits and slows down curing compared to non-oxidized carbon black while improving certain physicochemical properties of the polymer composition, thus requiring a substantially longer curing time to achieve appropriate mechanical properties or using a relatively large amount of a curing accelerator to achieve a reasonable curing time and appropriate mechanical properties, either of which increases costs. Moreover, many curing accelerators have environmental and / or toxicity concerns. For example, N,N-diphenylguanidine (DPG), commonly used as a curing accelerator in curable rubber compositions, is currently classified as potentially toxic to reproduction according to the European REACH regulation. Therefore, it is necessary to minimize or avoid the use of such substances.

[0008] Therefore, it is desirable to provide a carbon black-based additive that improves the relevant properties of a polymer composition, such as a rubber composition exhibiting improved hysteresis for the manufacture of tires having low rolling resistance, without adversely affecting the curing properties of the polymer composition or requiring the need for expensive and potentially harmful auxiliary substances. The carbon black-based additive should further be provided in a form convenient for processing and handling.

[0009] Therefore, an object of the present invention is to provide a carbon black-based material that can impart the above-described properties to a polymer composition, such as a rubber compound, while reducing or avoiding the drawbacks of the prior art. The provision of the carbon black-based material should be achievable in an efficient and economical manner using readily available elements and processing techniques. The present invention particularly aims to provide a vulcanizable rubber composition that provides improved hysteresis suitable for the manufacture of tires without the reduction in curing properties or the need for potentially harmful curing accelerators seen in conventional oxidized carbon black additives. SUMMARY OF THE INVENTION

[0010] And now, surprisingly, it has been found that the above object can be achieved by a solid carbon black material comprising carbon black oxide having a pH of more than 7 as specified in the appended independent claim 1. Specific or preferred variants of the solid carbon black material of the present invention are described in the dependent claims.

[0011] The solid carbon black material of the present invention can be obtained by a method comprising the following: (i) providing carbon black oxide, (ii) treating the carbon black oxide with a base, preferably an aqueous alkali metal hydroxide solution, (iii) optionally, wet-beading the carbon black oxide.

[0012] The present invention also relates to a composition comprising a polymer component and the solid carbon black material according to the present invention, and an article prepared from such a composition. The composition can in particular be a vulcanizable rubber composition.

[0013] The solid carbon black material according to the present invention can be obtained from commercially available components in a low-cost and efficient manner using common processing techniques. Unlike liquid systems such as dispersions, for example, it is convenient to process and handle without potentially disturbing or diluting the carrier medium. The solid carbon black material according to the present invention imparts favorable physical properties to polymer compositions, and in particular has been found to result in significantly reduced hysteresis in rubber compositions, making it interesting particularly for the manufacture of energy-saving tires without affecting the curing properties. In fact, it has been found that a curable polymer composition containing the solid carbon black material according to the present invention can cure as rapidly as the corresponding composition containing non-carbon black oxide without the need for an additional curing accelerator. Thus, the solid carbon black material makes it possible to minimize or avoid the use of potentially harmful curing accelerators such as DPG.

[0014] These and any other features and advantages of the present invention will be described in more detail in the following description. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 shows the curing process by plotting the measured torque against time, comparing the corresponding rubber compositions having non-oxidized carbon black (Example 1) and conventional acidic oxidized carbon black (Example 2) with a rubber composition containing the solid carbon black material according to the present invention (Example 3) (each having different concentrations of curing accelerators). [Modes for carrying out the invention]

[0016] As used herein, the term "contains" is understood to be open-ended and not to exclude the presence of additional unspecified or unenumerated elements, materials, components, or method steps. The terms "include," "contain," and similar terms are understood to be synonymous with "contains." As used herein, the term "consists of" is understood to exclude the presence of any unspecified elements, components, or method steps.

[0017] As used herein, the singular forms of “a,” “an,” and “the” encompass multiple referents unless the context clearly indicates otherwise.

[0018] Unless otherwise noted, the numerical parameters and ranges described in the following specification and the attached claims are approximate. While the broad ranges and parameters of the present invention are approximate, the numerical values ​​shown in the specific examples are reported as accurately as possible. However, any numerical values ​​will inevitably contain errors arising from the standard deviation in their respective measurements.

[0019] Furthermore, it should be understood that any numerical range listed herein is intended to encompass all subranges belonging to it. For example, the range "1 to 10" is intended to encompass all subranges between the listed minimum value of 1 and the listed maximum value of 10, and any subranges encompassing them, i.e., all subranges starting with a minimum value of 1 or greater and ending with a maximum value of 10 or less, for example, all subranges between 1 to 6.3, 5.5 to 10, or 2.7 to 6.1.

[0020] As described above, the present invention relates to a solid carbon black material containing oxidized carbon black having a pH greater than 7.

[0021] As used herein, “carbon black material” refers to a material based on one or more types of carbon black. Therefore, a carbon black material typically contains at least 50% by weight, for example, at least 70% by weight, at least 80% by weight, typically at least 90% by weight, at least 95% by weight, at least 98% by weight, at least 99% by weight, at least 99.5% by weight, or at least 99.9% by weight of one or more types of carbon black, based on the total solids weight of the material. Thus, a carbon black material can consist substantially of carbon black. The phrase “substantially of” as used herein means that even if the material contains substances other than those listed, they generally exist only as impurities that are not intentionally added and do not significantly affect the properties of the material. For example, the amount of such unlisted substances other than carbon black in the material may be 0.1% by weight or less. A carbon black material may, for example, consist of carbon black, i.e., 100% by weight of one or more types of carbon black.

[0022] As used herein, “carbon black” means a material containing, based on its total weight, substantially more than, for example, 80% by weight, 90% by weight, or 95% by weight of carbon produced by controlled partial pyrolysis of one or more hydrocarbon precursors. Various industrial methods for producing carbon black are known, such as furnace processes, gas black processes, acetylene black processes, thermal black processes, or lamp black processes. The production of carbon black is well known in the art itself and is outlined, for example, in J.-B. Donnett et al., “Carbon Black: Science and Technology,” 2nd edition, so it will not be described in further detail here. The carbon black material used in the implementation of the present invention may include a single type of carbon black or a mixture of two or more different carbon black grades.

[0023] As described above, the solid carbon black material according to the present invention includes oxidized carbon black. The term "oxidized carbon black," as used herein, refers to carbon black that has been subjected to oxidation and therefore contains oxygen-containing functional groups. Thus, unlike non-oxidized carbon black, oxidized carbon black generally has a significant oxygen content and contains oxygen-containing functional groups, but are not limited to quinone groups, carboxyl groups, phenolic groups, lactol groups, lactone groups, anhydride groups, and ketone groups.

[0024] Carbon oxide can be produced by various methods known in the art, such as those disclosed in U.S. Patent No. 6,120,594 and U.S. Patent No. 6,471,933. Suitable methods include, for example, the oxidation of carbon black materials using peroxides such as hydrogen peroxide, persulfates such as sodium persulfate and potassium persulfate, hypohalites such as sodium hypochlorite, ozone or oxygen gas, transition metal-containing oxidizing agents such as permanganates, osmium tetroxide, chromium oxide, cerium ammonium nitrate, or oxidizing acids such as nitric acid and perchloric acid, as well as mixtures or combinations thereof. Conventional carbon oxide has acidic functionality and typically exhibits a pH in the range of 2 to 6.

[0025] The carbon black oxide used in the solid carbon black material of the present invention, conversely, has basic rather than acidic functionality. In other words, the carbon black oxide according to the present invention has a pH greater than 7. For example, the carbon black oxide according to the present invention can have a pH of 7.1 or higher, for example, 7.2 or higher, 7.5 or higher, 7.8 or higher, 8.0 or higher, 8.5 or higher, 9.0 or higher, 9.5 or higher, or 10.0 or higher. For example, the carbon black oxide according to the present invention can have a pH of 12.0 or lower, for example, 11.5 or lower, 11.0 or lower, 10.5 or lower, 10.0 or lower, 9.5 or lower, 9.0 or lower, or 8.5 or lower. This carbon black oxide can have a pH in a range between any of the above lower and upper limits. For example, the carbon black oxide according to the present invention can have a pH in the range of 7.1 to 12.0, for example, in the range of 7.2 to 10.5, in the range of 7.5 to 9.5, or in the range of 8.0 to 9.0. The pH of carbon oxide black is measured according to ASTM D1512-15b Test Method B - Sonic Slurry.

[0026] The degree of oxidation of the carbon oxide black used in the implementation of the present invention can vary. For example, the carbon oxide black may have an oxygen content of 0.5% by weight or more, for example, 1.0% by weight or more, 2.0% by weight or more, 3.0% by weight or more, 4.0% by weight or more, 5.0% by weight or more, 7.5% by weight or more, or 10.0% by weight or more, based on the total weight of the carbon oxide black. Typically, the oxygen content of the carbon oxide black does not exceed 20% by weight based on the total weight of the carbon oxide black material. For example, the carbon oxide black may have an oxygen content of 20% by weight or less, for example, 15% by weight or less, 10% by weight or less, 8.0% by weight or less, 7.0% by weight or less, 6.0% by weight or less, 5.0% by weight or less, or 4.0% by weight or less, based on the total weight of the carbon oxide black. The carbon oxide black according to the present invention may have an oxygen content in a range between any of the above lower and upper limits. For example, carbon oxide black can have an oxygen content ranging from 0.5% to 20.0% by weight, 1.0% to 15.0% by weight, 2.0% to 10.0% by weight, or 2.0% to 5.0% by weight, based on the total weight of the carbon oxide black material. The oxygen content can be measured by elemental analysis, as described in detail in the examples.

[0027] The carbon black oxide according to the present invention can be further characterized by the content of volatile substances. Each of the volatile components described in this specification is measured by thermogravimetric measurement at a temperature of 950 °C, as described in detail in the examples. For example, the carbon black oxide can have a volatile content of 1.0 wt% or more, such as 1.5 wt% or more, 2.0 wt% or more, 2.5 wt% or more, 3.0 wt% or more, 3.5 wt% or more, 4.0 wt% or more, 5.0 wt% or more, 7.5 wt% or more, or 10.0 wt% or more, based on the total weight of the carbon black oxide. For example, the carbon black oxide can have a volatile content of 20.0 wt% or less, such as 15.0 wt% or less, 10.0 wt% or less, 8.0 wt% or less, 7.0 wt% or less, 6.0 wt% or less, or 5.0 wt% or less, based on the total weight of the carbon black oxide. The carbon black oxide according to the present invention can have a volatile content within the range between any of the above lower limit values and upper limit values. For example, the carbon black oxide can have a volatile content in the range of 1.0 wt% to 20 wt%, 1.0 wt% to 15.0 wt%, 2.0 wt% to 10.0 wt%, or 3.0 wt% to 5.0 wt%, based on the total weight of the carbon black oxide material.

[0028] The carbon black oxide used in the present invention can be further characterized by the BET surface area, the statistical thickness surface area (STSA), the oil absorption amount (OAN), the oil absorption amount of the compressed sample (COAN), or the iodine adsorption amount (more specifically described below), or any combination thereof.

[0029] The carbon black oxide according to the present invention, for example, has a BET surface area of 50 m 2 / g or more, such as 60 m 2 / g or more, 70 m 2 / g or more, 75 m 2 / g or more, 80 m 2 / g or more, 85 m 2 / g or more, 90 m 2 / g or more, or 95 m 2 / g or more. The carbon black oxide, for example, has a BET surface area of 500 m 2Less than / g, for example, 400m 2 / g or less, 300m 2 / g or less, 250m 2 / g or less, 200m 2 / g or less, 150m 2 / g or less, 130m 2 / g or less, 120m 2 / g or less, 110m 2 / g or less, or 100m 2 It can have a BET surface area of ​​less than or equal to / g. The carbon oxide black according to the present invention can have a BET surface area within the range between either the lower limit or the upper limit of the above. For example, the BET surface area of ​​the carbon oxide black according to the present invention is 50 to 500 m². 2 / g, for example, 70-300m 2 / g, typically 75-250mg 2 / g, for example, 80-200m 2 / g, or 90-150m 2 It can be in the range of / g. The BET surface area can be measured according to ASTM D6556-17.

[0030] The carbon oxide black used in this invention is 30m 2 / g or more, for example, 40m 2 / g or more, 50m 2 / g or more, 60m 2 / g or more, 70m 2 / g or more, 75m 2 / g or more, 80m 2 / g or more, or 85m 2 It can have a statistical thickness surface area (STSA) of 500 m² or more. Carbon oxide black can, for example, have a surface area of ​​500 m². 2 Less than / g, for example, 400m 2 / g or less, 300m 2 / g or less, 250m 2 / g or less, 200m 2 / g or less, 150m 2 / g or less, 130m 2 / g or less, 120m 2 / g or less, 110m 2 / g or less, or 100m 2It can have an STSA of 30-500 m / g or less. The carbon oxide black according to the present invention can have an STSA in a range between either the lower limit or the upper limit of the above. For example, the carbon oxide black of the present invention may have an STSA of 30-500 m / g. 2 / g, for example, 50-400m 2 / g, 60-300m 2 / g, 70-200m 2 / g, 80-150m 2 / g, or 85-120m 2 It can have an STSA in the range of / g. Statistical Thickness Surface Area (STSA) can be measured according to ASTM D6556-17.

[0031] The carbon oxide black used in the present invention may have an oil absorption rate (OAN) measured according to ASTM D2414-18 of 50 mL / 100 g or more, for example, 60 mL / 100 g or more, 70 mL / 100 g or more, 80 mL / 100 g or more, 90 mL / 100 g or more, or 100 mL / 100 g or more. For example, carbon oxide black may have an oil absorption rate (OAN) measured according to ASTM D2414-18 of 150 mL / 100 g or less, for example, 140 mL / 100 g or less, 130 mL / 100 g or less, 120 mL / 100 g or less, or 110 mL / 100 g or less. The carbon oxide black according to the present invention may have an oil absorption rate (OAN) measured according to ASTM D2414-18 within a range between any of the above lower and upper limits. For example, the carbon oxide black of the present invention may have an oil absorption rate (OAN) measured according to ASTM D2414-18 in the range of 50-150 mL / 100 g, for example, 60-140 mL / 100 g, 70-130 mL / 100 g, 80-120 mL / 100 g, or 90-110 mL / 100 g.

[0032] The carbon oxide black according to the present invention may further have a compressible oil absorption capacity (COAN) of 50 mL / 100 g or more, for example, 60 mL / 100 g or more, 70 mL / 100 g or more, 80 mL / 100 g or more, 90 mL / 100 g or more, or 95 mL / 100 g or more. The carbon oxide black according to the present invention may have a compressible oil absorption capacity (COAN) of 150 mL / 100 g or less, for example, 140 mL / 100 g or less, 130 mL / 100 g or less, 120 mL / 100 g or less, 110 mL / 100 g or less, or 100 mL / 100 g or less. The carbon oxide black according to the present invention may have a compressible oil absorption capacity (COAN) in a range between any of the above lower and upper limits. For example, the carbon oxide black of the present invention can have a Compression Oil Absorption Annuity (COAN) in the range of 50-150 mL / 100g, for example, 60-140 mL / 100g, 70-130 mL / 100g, 80-120 mL / 100g, or 90-100 mL / 100g. The COAN can be measured according to ASTM D3493-18.

[0033] The carbon oxide black according to the present invention may further have an iodine adsorption amount measured according to ASTM D1510-19 of 20 mg / g or more, for example, 30 mg / g or more, 40 mg / g or more, 50 mg / g or more, 55 mg / g or more, or 60 mg / g or more. The carbon oxide black according to the present invention may have an iodine adsorption amount measured according to ASTM D1510-19 of 300 mg / g or less, for example, 250 mg / g or less, 200 mg / g or less, 150 mg / g or less, 120 mg / g or less, 100 mg / g or less, 90 mg / g or less, 80 mg / g or less, or 70 mg / g or less. The carbon oxide black according to the present invention may have an iodine adsorption amount measured according to ASTM D1510-19 within a range between any of the above lower and upper limits. For example, the carbon black oxide of the present invention may have an iodine adsorption capacity measured according to ASTM D1510-19 in the range of 20 to 300 mg / g, for example, 30 to 200 mg / g, 40 to 120 mg / g, or 50 to 80 mg / g.

[0034] The carbon oxide black produced by the method of the present invention can be obtained by treating initial carbon oxide black with a base.

[0035] Initial carbon black oxide can be produced by any of the methods known in the art for preparing carbon black oxide, such as those described above. Precursor carbon black can be oxidized using an oxidizing agent, such as peroxides like hydrogen peroxide, persulfates like sodium persulfate and potassium persulfate, hypohalites like sodium hypochlorite, ozone or oxygen gas, transition metal-containing oxidizing agents such as permanganates, osmium tetroxide, chromium oxide, cerium ammonium nitrate, or oxidizing acids like nitric acid and perchloric acid, as well as mixtures or combinations thereof. For example, carbon black oxide may be ozone-oxidized carbon black. The precursor carbon black subjected to oxidation may be any type of carbon black, such as furnace black, lamp black, gas black, or a combination thereof. Such carbon blacks are commercially available from various manufacturers, such as Orion Engineered Carbons. Therefore, carbon black oxide may include, but is not limited to, furnace black oxide, lamp black oxide, gas black oxide, or a combination thereof. Preferably, carbon black oxide includes furnace black oxide.

[0036] The initial carbon oxide black provided in this manner is generally acidic and typically exhibits a pH in the range of 2 to 6. For example, the initial carbon oxide black to be treated with a base may contain 20 μmol or more of carboxylic acid groups per gram of carbon black, e.g., 50 μmol or more, 100 μmol or more, 150 μmol or more, 200 μmol or more, or 300 μmol or more of carboxylic acid groups. For example, the initial carbon oxide black to be treated with a base may contain 500 μmol or less of carboxylic acid groups per gram of carbon black, e.g., 400 μmol or less, 350 μmol or less, 300 μmol or less, 250 μmol or less, or 200 μmol or less of carboxylic acid groups. The initial carbon oxide black to be treated with a base may contain carboxylic acid groups in a range between any of the above lower and upper limits. For example, the carbon oxide black of the present invention may contain 50 to 500 μmol of carboxylic acid groups per gram of carbon black, or 100 to 300 μmol of carboxylic acid groups. The amount of carboxylic acid groups can be measured with high accuracy by the titration method described in J. Ackermann and A. Kruger, "Highly sensitive and reproducible quantification of oxygenated surface group on carbon nanomaterials," Carbon 163 (2020), 56-62.

[0037] Next, the acid-functionalized carbon black oxide is treated with a base to form the carbon black oxide according to the present invention having a pH greater than 7. In principle, any known type of base can be used for this treatment. Suitable bases include, but are not limited to, metal oxides, metal hydroxides, metal carbonates, and other basic metal salts, ammonia, and amines, which are typically used as aqueous solutions. Bases that can be preferably used according to the present invention include, for example, aqueous solutions of alkali metal hydroxides or alkaline earth metal hydroxides, such as sodium hydroxide, potassium hydroxide, or calcium hydroxide. A single base or a mixture of two or more different bases can be used. The base is typically used in an equimolar amount or a moderate excess amount relative to the acidic groups in the carbon black oxide. For example, the amount of base used may be such that the base-to-acidic group ratio in the initial carbon black oxide to be treated is 0.8:1 or higher, for example, 0.9:1 or higher, 1:1 or higher, 1.1:1 or higher, 1.2:1 or higher, or 1.5:1 or higher. The amount of base used may be such that the base-to-acid group equivalent ratio in the initial carbon black oxide to be treated is 2:1 or less, for example, 1.8:1 or less, or 1.5:1 or less, or 1.3:1 or less, or 1.2:1 or less, or 1.1:1 or less. This equivalent ratio may be within the range of any one of the lower and upper limits mentioned above. For example, the base-to-acid group equivalent ratio in the initial carbon black oxide to be treated may be in the range of 0.8:1 to 2:1, for example, 0.9:1 to 1.5:1, or 0.9:1 to 1.2:1, or 1:1 to 1.1:1. Treatment with a base may include thoroughly mixing the base with the carbon black oxide. Mixing can typically be done using a standard mixing apparatus over a period of up to 10 minutes. However, other forms of treatment, such as spraying the base onto the carbon black oxide, can also be used.

[0038] Treatment with a base can convert at least some of the acidic functional groups of the initial carbon black oxide into their neutralized forms. Therefore, the carbon black oxide according to the present invention can contain salt groups. For example, the carbon black oxide according to the present invention can contain carboxylate groups such as alkali metal carboxylates or ammonium carboxylates. For example, the carbon black oxide according to the present invention can contain carboxylate groups in amounts of 20 μmol or more, 50 μmol or more, 100 μmol or more, 150 μmol or more, 200 μmol or more, or 300 μmol or more per gram of carbon black. For example, the carbon black oxide according to the present invention can contain carboxylate groups in amounts of 500 μmol or less, for example, 400 μmol or less, 350 μmol or less, 300 μmol or less, 250 μmol or less, or 200 μmol or less per gram of carbon black. The carbon black oxide according to the present invention can contain carboxylate groups in amounts between any of the above lower and upper limits. For example, the carbon black oxide of the present invention may contain 50 to 500 μmol of carboxylate groups per gram of carbon black, or 100 to 300 μmol of carboxylate groups. The amount of carboxylate groups can be determined as the difference between the amount of carboxylic acid groups measured before base treatment and the amount of carboxylic acid groups measured after base treatment.

[0039] The acidic functional groups of initial carbon oxide black may be almost or completely neutralized by base treatment. For example, the acidic functional groups may be neutralized to a degree of at least 80%, e.g., at least 90%, at least 95%, at least 99%, at least 99.5%, at least 99.9%, or 100%. Carbon oxide black with a pH greater than 7 may contain, for example, less than 20 μmol / g, less than 10 μmol / g, or less than 5 μmol / g of carboxylic acid groups, or may be substantially free of carboxylic acid groups. "Substantially free of carboxylic acid groups" means that the amount of carboxylic acid groups is not measurable or does not have a measurable effect on the properties of the carbon oxide black.

[0040] The carbon oxide black according to the present invention can be further characterized by its aggregate particle size distribution (ASD). The aggregate particle size distribution can be measured by light scattering using a Brookhaven BI-DCP disk centrifuge, as described in U.S. Patent Application Publication No. 2019 / 0062522A1. The carbon oxide black according to the present invention has a mode diameter D, which is the most frequent diameter in the ASD, such as at least 10 nm, for example, at least 20 nm, at least 30 nm, at least 40 nm, at least 50 nm, at least 60 nm, or at least 70 nm. modeIt can have (also called "modes"). For example, it can have modes of 500 nm or less, e.g., 300 nm or less, 250 nm or less, 200 nm or less, 150 nm or less, or 100 nm or less. The carbon oxide black according to the present invention can have modes in a range between any of the above lower and upper limits. For example, it can have modes in the range of 10 nm to 500 nm, 30 nm to 200 nm, or 50 nm to 100 nm. The width of the particle size distribution can be expressed by its full width at half maximum (FWHM), also called ΔD50. According to DIN ISO 15825, ΔD50 represents the width of the distribution measured at the half-maximum point of the mode. The aggregate particle size distribution of the carbon oxide black according to the present invention can have a ΔD50 of, for example, at least 10 nm, e.g., at least 20 nm, at least 30 nm, at least 40 nm, at least 50 nm, or at least 60 nm. For example, it can have a ΔD50 of 300 nm or less, for example, 250 nm or less, 200 nm or less, 150 nm or less, 100 nm or less, or 80 nm or less. The carbon black oxide according to the present invention can have a ΔD50 in a range between any of the above lower and upper limits. For example, it can have a ΔD50 in the range of 10 nm to 300 nm, for example, 30 nm to 150 nm, or 50 nm to 80 nm. The aggregate particle size distribution of the carbon black oxide according to the present invention largely corresponds to one of the selected precursor carbon blacks that is the source of preparation of the carbon black oxide, and can be adjusted accordingly as desired or as needed.

[0041] The carbon black material containing carbon black oxide according to the present invention is in solid form. For example, the solid carbon black material may be in powder form. Alternatively, the solid carbon black material may be in the form of beads or pellets. Thus, as will be understood by those skilled in the art, the solid carbon black material is distinguished from carbon black materials that are provided in other (non-solid) forms, such as liquid dispersions. Beads or pellets can be formed by wet or dry pelletizing the respective powdered starting materials. In such cases, forming the solid carbon black material generally further involves pelletizing the carbon black oxide, which can be done simultaneously with or after the base treatment described above. According to the present invention, wet pelletizing can preferably be used, where the base can be used as a wet bead medium, and the wet bead medium may optionally contain an organic binder and / or one or more pelletizing agents as auxiliary components. Pelleting of powdered carbon black oxide can be carried out using common pelletizing equipment such as a stirring granulation system, such as a ring-layer mixer granulator, in a one-step wet pelletizing process similar to EP2913368A1, for example. The resulting pellets can be further dried after the pelletizing step, for example, in a rotary drum dryer. Drying can be carried out at temperatures in the range of 100°C to 250°C, for example, 110°C to 180°C or 120°C to 160°C. The drying time can be appropriately selected to achieve a desired degree of dryness, for example, a residual moisture content of less than 1%. The characteristics of the pellets can be controlled by adjusting the parameters of the pelletizing process. For example, if the weight ratio of wet bead medium to powder is constant, an increased rotational speed of the granulator generally results in smaller pellets, while an increase in the weight ratio of wet bead medium to powder is advantageous for the formation of larger pellets. The as-prepared pelletized carbon black material according to the present invention can be characterized by a pellet size distribution that can be measured according to ASTM D1511-10. In particular, the proportion of undesirable fine powder may be low in the pelletized carbon black material according to the present invention.Therefore, it may contain pellets having a size of less than 0.125 mm, which may be less than 1% by weight, less than 0.5% by weight, or less than 0.3% by weight, based on the total weight of the pelletized carbon black material. The proportion of pellets having a size of less than 0.5 mm may be 15% by weight or less, e.g., 10% by weight or less, 5% by weight or less, or 2% by weight or less, based on the total weight of the pelletized carbon black material. The amount of pellets having an intermediate size range of 1.0 mm to 2.0 mm, which is considered desirable in terms of processing characteristics, may be 30% by weight or more, e.g., 40% by weight or more, or 50% by weight or more, based on the total weight of the pelletized carbon black material. The prepared pelletized carbon black material can be further size-separated using standard methods such as sieving classification, if necessary, to obtain material with appropriate pellet sizes.

[0042] The solid carbon black material may contain carbon black oxide having a pH greater than 7 in any amount. Based on the total weight of the solid carbon black material, the solid carbon black material may contain carbon black oxide having a pH greater than 7 in amounts such as at least 10% by weight, at least 30% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, or at least 99% by weight. The solid carbon black material may contain carbon black oxide having a pH greater than 7 in amounts of 100% by weight or less, for example, 99.5% by weight or less, 99.0% by weight or less, 95% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, or 50% by weight or less. The solid carbon black material may contain carbon black oxide having a pH greater than 7 in amounts between any of the above lower and upper limits, for example, in the range of 10 to 100% by weight or 50% to 99% by weight. Preferably, the solid carbon black material consists of carbon black oxide having a pH greater than 7.

[0043] The solid carbon black material may optionally contain one or more other carbon blacks in addition to the oxidized carbon black having a pH greater than 7 as described above. Such any other carbon blacks are not particularly limited and may include any conventional non-oxidized or oxidized carbon black, such as conventional acid-functionalized oxidized carbon black and / or ASTM-grade carbon blacks selected from the N100-N900 series of classifications according to ASTM D1765. When such other carbon blacks are used, the solid carbon black material contains them in an amount typically less than 50% by weight, for example, 30% by weight or less, 20% by weight or less, 10% by weight or less, 5% by weight or less, 1% by weight or less, or 0.5% by weight or less, based on the total weight of the solid carbon black material. Preferably, the solid carbon black material does not contain any carbon black other than oxidized carbon black having a pH greater than 7.

[0044] The solid carbon black material may optionally contain components other than carbon black. Therefore, the solid carbon black material may contain one or more auxiliary substances or processing aids that are conventionally used in the art in which it is formulated, such as flow additives, rheological modifiers, pelletizers, or fillers. Such optional auxiliary substances, if used, are used in amounts commonly used in the art to achieve their respective intended functionalities. Typically, the solid carbon black material according to the present invention may contain optional components other than carbon black in a total amount of 20% by weight or less, for example, 10% by weight or less, 5% by weight or less, 1% by weight or less, or 0.5% by weight or less, based on the total weight of the solid carbon black material. Preferably, the solid carbon black material does not contain such optional components other than carbon black.

[0045] As described above, the present invention also relates to compositions comprising the solid carbon black material and polymer components of the present invention. In other words, the present invention also relates to the use of solid carbon black material in polymer compositions.

[0046] The term “composition,” as used herein, refers to a material composed of multiple constituent chemical species or components. The term “polymer composition” refers to a composition containing at least one polymer component. Thus, a “polymer composition” may include a single type of polymer material or two or more different types of polymer materials as polymer components. A “polymer material” is understood to be a material consisting essentially of polymers. The term “polymer” is used herein in its general sense in the art and refers to a macromolecule, i.e., a compound having a relatively high molecular weight (e.g., 500 da or more), whose structure actually or conceptually includes multiple repeating units (also called “mers”) derived from chemical species with relatively low molecular weights.

[0047] The compositions according to the present invention may, in particular, be curable compositions, such as vulcanizable rubber compositions. The term “vulcanizable rubber composition” refers to a composition of rubber components which can be cured by vulcanization in the presence of a vulcanized product and which optionally contains various further components conventionally used in the art of rubber compounding. The terms “curable” and “vulcanizable” are used interchangeably throughout this specification unless otherwise specified and refer to a chemical reaction which links polymer chains together with a crosslinking agent or vulcanizing agent. The curing reaction can be induced by any means known in the art, such as light, moisture, heat and / or the addition of a crosslinking agent.

[0048] However, the polymer materials that can be used as polymer components in the compositions according to the present invention are not limited and may include any type of organic or inorganic polymer material. Polymer materials that can be used according to the present invention include thermoplastic polymers, duroplastics or thermosetting polymers, and mixtures or combinations thereof. For example, polymer materials that can be used in the compositions of the present invention include polyethers such as epoxy, acrylic, urethane, polyester, polycarbonate, polysulfone, polyimide, and polyethersulfone, and polyolefins such as low-density, medium-density and high-density polyethylene, ethylene-propylene copolymers (which may be randomly arranged or block-arranged), polypropylene-maleic anhydride, polystyrene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, ethylene vinyl acetate, ethylene-acrylic acid copolymer, vinyl chloride-polypropylene copolymer, polyisobutylene, polybutadiene, and crosslinked polyethylene (chemical, thermal, UV or E-beam (EB) crosslinked), and polyphenylene sulfide, polyetheretherketone, polyetherimide, polyarylsulfone and polypropylene oxide-modified polyethersulfone, or mixtures or combinations thereof.

[0049] Elastomers and rubber materials are particularly useful as polymer materials for carrying out the present invention. Therefore, the polymer components of the compositions according to the present invention may include one or more rubbers or elastomers. Rubbers and elastomers that can be used according to the present invention include those containing olefinic unsaturated rubbers, i.e., diene rubbers or elastomers, as well as non-diene rubber materials or elastomers. The terms “rubber,” “rubber material,” and “elastomer” may be used interchangeably throughout this specification unless otherwise specified. The term “diene rubber” is intended to include both natural rubber and synthetic rubber, or mixtures thereof. Natural rubber can be used in its raw form and in various processed forms conventionally known in the art of rubber processing. Synthetic diene rubber may be any rubber containing at least one diene monomer that constitutes rubber, either alone or together with other monomers. Examples of suitable diene-based rubber materials in the implementation of the present invention include, but are not limited to, natural rubber, emulsion-styrene-butadiene rubber, solution-styrene-butadiene rubber, polybutadiene, polyisoprene, ethylene-propylene-diene rubber (EPDM), butyl rubber and halogenated butyl rubber, acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, polychloroprene, or any combination thereof. Examples of suitable non-diene-based rubber materials in the implementation of the present invention include, but are not limited to, ethylene-propylene rubber (EPM), chlorinated polyethylene, chlorosulfonated polyethylene, acrylate rubber, ethylene vinyl acetate rubber, ethylene-acrylic rubber, epichlorohydrin rubber, silicone rubber, fluorosilicone rubber, fluorocarbon rubber, and any combination thereof. Suitable rubbers also include functionalized rubbers and rubbers bonded to silicon or tin. For example, rubber can be functionalized with functional groups such as amines, alkoxys, silyls, thiols, thioesters, thioethers, sulfanyls, mercaptos, sulfides, or combinations thereof.One or more functional groups may be primary, secondary, or tertiary, and may be located at one or both chain ends (e.g., α, ω functionalization), may be suspended from the polymer backbone, and / or provided within the polymer backbone. The rubber according to the present invention may also be partially crosslinked. Therefore, before use in the compositions of the present invention, a portion of the polymer chain of the rubber material may be crosslinked with or without a coupling agent. The polymer component may include a single rubber or elastomer, or a mixture or combination of one or more rubbers or elastomers, optionally combined with one or more other polymer materials such as those described above. Examples of specific rubber materials that can be used in carrying out the present invention include SMR10 rubber, commercially available from Weber & Shear; Vamac® Ultra HT, commercially available from DuPont; Noxtite RE461®, commercially available from Unimatec; Europrene® 1500 and Europrene SOL R C2525, commercially available from Versalis; or Keltan® 4455 rubber, commercially available from Alantheo.

[0050] The polymer component typically represents the main component of the composition according to the present invention. It may constitute, for example, 30% by weight or more based on the total solids weight of the composition. For example, the polymer component may constitute 40% by weight or more, for example 50% by weight or more, or 60% by weight or more, of the composition based on the total solids weight of the composition. For example, the polymer component may constitute 99% by weight or less, for example 95% by weight or less, 90% by weight or less, 85% by weight or less, 80% by weight or less, 75% by weight or less, or 70% by weight or less, of the composition based on the total solids weight of the composition. The composition according to the present invention may contain the polymer component in an amount between any of the above lower and upper limits. For example, the polymer component may be included in an amount ranging from 30% by weight to 90% by weight, for example 50% by weight to 80% by weight, based on the total solids weight of the composition.

[0051] The composition further contains, in addition to the polymer components, the solid carbon black material according to the present invention as a more characteristic component. For example, the composition of the present invention may contain the solid carbon black material in an amount of 1 phr or more, e.g., 2 phr or more, 5 phr or more, 10 phr or more, 20 phr or more, 30 phr or more, 40 phr or more, 50 phr or more, or 60 phr or more. For example, the composition of the present invention may contain the solid carbon black material in an amount of 150 phr or less, e.g., 100 phr or less, 90 phr or less, 80 phr or less, or 70 phr or less. The composition of the present invention may contain the solid carbon black material in an amount between any of the above lower and upper limits. For example, the solid carbon black material may be included in the composition in an amount ranging from 1 to 100 phr, e.g., 10 to 100 phr, or 30 to 80 phr. As used herein, the term "phr" refers to parts by weight of each listed material (here, the solid carbon black material) per 100 parts by weight of the polymer component.

[0052] The compositions according to the present invention may optionally contain one or more additional fillers in addition to the solid carbon black material of the present invention. Such optional filler materials include, but are not limited to, conventional carbon black materials, carbon nanotubes, carbon fibers, graphite and metal fibers, as well as metal compounds such as silica, organosilica, titanium dioxide, calcium carbonate, clay, calcium silicate, zinc sulfide, hydrated alumina and calcined magnesia. When used, such fillers are typically used in amounts up to 30 phr, for example, 0.1 to 20 phr or 1 to 10 phr.

[0053] The compositions according to the present invention may also contain at least one vulcanizing agent. Possible vulcanizing agents include any vulcanizing agent known in the art, such as sulfur and sulfur donors. Suitable sulfur donors for carrying out the present invention include, for example, dithioalkanes, dicaprolactam sulfides, polysulfide polymers, sulfur olefin adducts, thiram, and sulfonamides having at least two sulfur atoms in the sulfur crosslinks. Preferably, elemental sulfur can be used. The vulcanizing agent may typically be used in the compositions according to the present invention in an amount ranging from 0.5 to 10 phr, for example, from 1 to 5 phr.

[0054] The compositions according to the present invention may further contain one or more other additives commonly used in the field of pharmaceuticals. Such additives include, for example, curing aids such as primary and secondary vulcanization accelerators, activators and pre-vulcanization inhibitors, as well as treatment additives such as oils, waxes, resins, plasticizers, softeners or theology modifiers, pigments, decoagulants, coupling agents, surfactants, biocides and anti-degradation agents (such as heat or light stabilizers, antioxidants and anti-ozone agents). Those skilled in the art will select any such additives and their respective amounts according to the desired properties and / or applications of the polymer composition. Useful primary and secondary vulcanization accelerators include, for example, guanidine, dicarbamates, dithiocarbamates, thiuram, thioureas, 2-mercaptobenzothiazole, benzothiazole sulfonamides, aldehyde amines, amines, disulfides, thiazoles, xanthetes, and sulfenamides. A specific example is N-tert-butyl-2-benzothiadylsulfenamide, which is commercially available from Rhenogran Additives under the trade name Rhenogran TBBS-80. One advantage of the present invention is that the vulcanizable polymer compositions according to the present invention can be cured within a reasonable time using or without relatively small amounts of vulcanization accelerators. Therefore, if vulcanization accelerators are used, they can be used in amounts of less than 3 phr, less than 2 phr, or even less than 1 phr, for example, in the range of 0.05 to 3 phr or 0.5 to 2 phr. This makes it possible to avoid or minimize the use of accelerators such as DPG under environmental and / or toxic concerns. Compositions according to the present invention may substantially not contain guanidine-type accelerators such as DPG, o-tolylbiguanidine (OTBG), or 1,3-di-o-tolylguanidine (DOTG). "Substantially guanidine-type accelerator-free" means, as used herein, that guanidine-type accelerators are not intentionally used. Therefore, if present, they are present in the composition according to the present invention as low amounts of impurities that do not significantly affect the properties of the composition, such as an amount of less than 0.1% by weight based on the total solids weight of the composition.The compositions according to the present invention may, for example, be completely guanidine-type accelerator-free, that is, they may not contain guanidine-type accelerators. Suitable vulcanization activators that can be used in the compositions according to the present invention include, for example, combinations of zinc oxide with fatty acids such as stearic acid, lauric acid, palmitic acid, oleic acid, or naphthenic acid. When used, such activators are typically used in amounts of 1 to 10 phr, for example, 2 to 5 phr.

[0055] The compositions according to the present invention may optionally further contain water and / or one or more organic solvents. For example, water and / or organic solvents can serve as dissolving or dispersion media for polymer components and solid carbon black materials. The compositions according to the present invention may be liquid compositions, such as aqueous dispersions or organic dispersions. The compositions according to the present invention may be ink formulations or coating or printing compositions, for example.

[0056] The compositions of the present invention are typically provided as bulk materials. The materials can be processed by common plastic or elastomer processing techniques. Compositions according to the present invention can be obtained, for example, by combining the solid carbon black material and optional components (if used) of the present invention with a polymer component and mixing them to disperse the solid carbon black material and optional components (if used) in the polymer component. Dispersion can be achieved by any means known in the art, such as by mixing, stirring, grinding, kneading, ultrasonic, dissolving, shaker mixer, rotor stirring dispersion assembly, or high-pressure homogenizer, or a combination thereof. For example, a laboratory mixer having a meshing rotor shape can be used. Dispersion can be carried out, for example, until the carbon black material is homogeneously dispersed in the polymer component and the dispersion index is 95% or higher, preferably 97% or higher, or 99% or higher, according to ASTM D2663-88 Test Method B.

[0057] The composition according to the present invention can be prepared, for example, by a multi-step process. First, the solid carbon black material and any non-curing additives, if used, can be added simultaneously or sequentially to the polymer component. The polymer component, solid carbon black material, and additives, if used, can then be mixed, if used, at a temperature typically in the range of 40°C to 160°C for a total mixing time of less than 10 minutes, for example, in the range of 2 to 8 minutes. Subsequently, the resulting mixture can be blended with one or more curing additives at a temperature below 115°C for less than 5 minutes, typically less than 3 minutes, preferably about 2.5 minutes.

[0058] The method may include further steps such as extruding the product or cooling it to room temperature and storing it for further processing. The method may further include a curing step, which can be carried out by subjecting the composition to thermosetting conditions, for example, a temperature of 120-200°C for 5 minutes to 3 hours. Curing can be carried out, for example, in a curing press at a temperature of 140-180°C for 5-60 minutes at a pressure of 100-150 bar.

[0059] As can be understood, the compositions according to the present invention can be used in a variety of technical applications requiring polymer-based materials having carbon black fillers to impart antistatic or conductive properties, color, mechanical reinforcement, and / or low hysteresis properties. Accordingly, the present invention also relates to articles manufactured from or containing the above-mentioned antistatic or conductive polymer compositions. Non-limiting examples of such articles include, for example, tires, tire components (such as tire treads), cable sheaths, tubes, drive belts, conveyor belts, roll covers, shoe soles, sealing members, profiles, damping elements, coatings, or colored or printed articles. Due to the exceptional combination of suitable mechanical properties achievable by rapid curing without requiring large amounts of accelerators and improved hysteresis properties, the vulcanizable rubber compositions according to the present invention are particularly interesting for the manufacture of energy-saving tires or tire components having reduced rolling resistance and heat accumulation. Examples of such tires include, but are not limited to, truck tires, passenger car tires, off-road tires, aircraft tires, agricultural tires, and earth mover tires.

[0060] The present invention will be further illustrated by the following embodiments. It should be understood that these embodiments are included for illustrative purposes only and should not be construed as limiting the invention. In particular, the scope of protection sought should not be limited by the specific embodiments disclosed below, but rather by the entire scope of the appended claims, which encompass any equivalent thereof. [Examples]

[0061] All parts and proportions referred to herein are by weight unless otherwise indicated.

[0062] Carbon black material As references, Printex® 60 and non-oxidizing furnace black (hereinafter referred to as carbon black A), commercially available from Orion Engineered Carbons, were used.

[0063] Furthermore, conventional acid-oxidized carbon black (hereinafter referred to as carbon black B), which has a surface area and structure similar to the reference black, was obtained by oxidizing Printex® 60 carbon black, which is commercially available from Orion Engineered Carbons.

[0064] Approximately 5 kg of carbon black A or B powder was wet-beaded. For this purpose, the powder was introduced into a stationary batch mixer (a so-called "Papenmeier" type GRP625 / 1.0, manufactured by Geppert Ruehrtechnik). Deionized water was then slowly added under stirring (300 rpm) until the carbon black began to granulate, typically in a weight ratio of approximately 1:1, followed by increasing the stirring speed to 600-800 rpm. The resulting mixture was then homogenized at 28 rpm for 10 minutes on a roller block with a plastic drum measuring 600 mm in length and 350 mm in diameter. The bead material was then dried in an oven at 120°C until the residual moisture content was less than 1%. The particle size distribution of the resulting pellets was measured as shown below.

[0065] The carbon black material according to the present invention (hereinafter referred to as carbon black C) was further prepared by treating carbon black B with an aqueous sodium hydroxide solution. For this purpose, approximately 5 kg of carbon black B powder was wet-beaded according to the above procedure, but using a 0.4 M aqueous sodium hydroxide solution instead of deionized water.

[0066] Table 1 summarizes the properties of the different types of bead-shaped carbon black used.

[0067] [Table 1]

[0068] Methods applied for characterizing carbon black The BET surface area was measured by nitrogen adsorption according to ASTM D6556-17.

[0069] Statistical thickness surface area (STSA) was measured according to ASTM D6556-17.

[0070] Iodine adsorption amount (IAN) was measured according to ASTM D1510-19.

[0071] Oil absorption capacity (OAN) was measured according to ASTM D2414-18.

[0072] The oil absorption capacity (COAN) of the compressed sample was measured according to ASTM D3493-18.

[0073] pH was measured using a WTW inoLab Multi9420IDS according to D1512-15b, Test Method B - Sonic Slurry.

[0074] The coloring strength was measured according to ASTM D3265-17.

[0075] Blackness level M Y It was measured according to DIN 55979-1989.

[0076] The volatile content at 950°C was measured using a thermogravimetric analyzer (TGA-701) manufactured by Fa.LECO Instrumente, following the procedure below. The weighing pan was dried at 650°C for 30 minutes. The carbon black material was stored in a desiccator with a desiccant before measurement. The baked-out weighing pan was loaded into the instrument, its weight was measured, and 0.5g to 10g of carbon black material was filled into it. The oven of the TGA instrument, with the sample-filled pan loaded, was then gradually heated to 105°C under automatic software control, drying the sample until a certain mass was achieved. Subsequently, the pan was closed with a lid, the oven was purged with nitrogen (99.9 vol% grade), and heated to 950°C. The oven temperature was maintained at 950°C for 7 minutes. The volatile content at 950°C was calculated using the following formula.

[0077]

number

[0078] The number of carboxylic acid groups per unit mass was measured according to the following procedure: Carbon black was dried overnight in a compartment dryer set to a temperature of 125°C. The hot carbon black material was removed from the dryer and cooled in a desiccator containing a desiccant. In three completely cleaned and dried Erlenmeyer flasks, each was measured m CB 1.5 ± 0.1 g of carbon black material was weighed, and 25 mL of 0.05 mol sodium bicarbonate aqueous solution (Titrisol grade diluted with bi-distilled water) was added to each. The air in the flask was replaced with nitrogen gas, the flask was sealed with a plug, and then secured by taping with Parafilm. The flask was placed in a shaker at 100 rpm overnight. The resulting suspension was then pressure filtered using nitrogen gas at a pressure of 5 bar. 10 mL of each filtrate was transferred to a beaker. 20 mL of 0.025 Molar sulfuric acid (Titrisol grade diluted with bi-distilled water) was added to each beaker, and the carbonates were removed by boiling briefly. Subsequently, the samples were titrated to pH 6.5 using 0.05 Molar sodium hydroxide solution (Titrisol grade diluted with bi-distilled water) and returned to the original sample. The required amount of sodium hydroxide solution V NaOH The amount was measured in mL with an accuracy of 3 decimal places. Two blanks were measured and the required amount of sodium hydroxide solution was averaged (V blank). , (Average). Using the following chemical formula, the concentration of carboxyl groups in μmol / g was calculated for all three samples, and the obtained values ​​were averaged.

[0079]

number

[0080] The oxygen content was measured by quantitative elemental analysis using an automated elemental analyzer (vario EL cube elemental analyzer, Elementar Analysensysteme) in accordance with DIN 51732-2014-07. 4 mg ± 1 mg of the dry carbon black to be analyzed was weighed into tin capsules on a scale with an accuracy of 1 μg. The filled capsules were then sealed in a capsule press under a helium atmosphere. Next, the prepared samples were introduced into a calibrated vario EL cube elemental analyzer, and their oxygen content was analyzed.

[0081] The pellet particle size distribution was measured according to ASTM D1511-10.

[0082] The aggregate particle size distribution was measured by light scattering using a Brookhaven BI-DCP disk centrifuge, in accordance with ISO 15825:2015-06.

[0083] Preparation of vulcanizable rubber compositions in Examples 1-3 The vulcanizable rubber compositions shown in Table 2 were prepared using different bead-shaped carbon blacks A to C according to the following procedure.

[0084] The preparation was carried out using a multi-stage mixing procedure. Each mixing step was performed in an internal mixer having a meshing rotor shape (GK1.5E).

[0085] First, the rubber component was added to the mixing chamber of an internal mixer operated at 45 rpm and a chamber temperature of 40°C, and plasticized for 30 seconds. Then, half the amounts of TDAE, ZnO, stearic acid, and each of the carbon black components were added and mixed for 75 seconds. The ram was lifted and washed, and then the remaining carbon black component was added and mixed for a further 135 seconds. During this step, care was taken to ensure that the maximum temperature did not exceed 160°C. The filling rate of the internal mixer was 0.68.

[0086] After storage for at least 12 hours, in the second mixing step, the mixture was stirred for 150 seconds in an internal mixer at 48 rpm and a chamber temperature of 60°C. During this step, care was taken to ensure that the maximum temperature did not exceed 155°C.

[0087] Next, sulfur and TBBS-80 were added to the mixture and stirred in an internal mixer at 33 rpm and a chamber temperature of 40°C for 2 minutes. During this step, care was taken to ensure that the maximum temperature did not exceed 110°C. The resulting mixture was then cooled to obtain the respective vulcanizable rubber compositions.

[0088] [Table 2]

[0089] Curing of the vulcanizable rubber compositions of Examples 1-3 The vulcanizable rubber compositions of Examples 1-3 were cured at 150°C for 20 minutes during curing press. The applied pressure was 120-150 bar.

[0090] The properties of the cured rubber composition obtained in this manner were tested as follows.

[0091] Mooney viscosity (ML(1+4)100℃) was measured according to ISO289-1:2015.

[0092] Hardness was measured according to DIN 53 505.

[0093] The bonded rubber was measured according to the following procedure. Approximately 0.2 g of the rubber sample was cut into small pieces, weighed using an analytical balance, and placed in a wire basket (320 mesh, stainless steel, 22 mm diameter, 40 mm height) filled with glass wool, ensuring that the sample did not come into contact with the wire basket. The sample-containing basket was placed in a 100 mL flask with a screw cap, and 50-60 mL of toluene (analytical grade) was added to obtain a minimum packing level of 20 mm above the bottom of the flask. The flask was left at a temperature of 23 ± 2 °C for 7 days, swirling it every morning and evening. The toluene was replaced after 1-3 days. After 7 days, the basket containing the bonded rubber gel was removed from the flask and allowed to release the solvent overnight in a fume hood. Subsequently, the sample was dried overnight in a box-type dryer until the mass became constant. After cooling to room temperature in a desiccator, the sample was weighed (m(dried gel)). The weight percentage of the bonded rubber relative to the mass of the original sample was calculated using the following formula.

[0094]

number

[0095] It was assumed that the mass of the carbon black filler in the gel was the same as the mass of the carbon black filler in the original sample (m(filler, original sample)).

[0096] Tensile strength, elongation at break, and modulus of elasticity at 100%, 200%, 300%, and 500% were measured according to DIN 53 504.

[0097] Tear resistance was measured using notched, angled specimens according to DIN ISO34-1:2016-09, Method B, Deformation (b), and the force required to enlarge the pre-formed notch was measured.

[0098] The results obtained are summarized in Table 3.

[0099] [Table 3]

[0100] The results in Table 3 show that by using oxidized carbon black in the rubber composition, it is possible to obtain rubber articles with significantly improved hysteresis properties, as demonstrated by the increase in bound rubber, compared to the corresponding unoxidized reference carbon black (see Examples 2 and 3 compared to Example 1). However, the use of conventional acid-functionalized oxidized carbon black significantly degrades the mechanical properties of the cured rubber composition, as demonstrated by the significant decrease in elastic modulus and tensile strength in Example 2 compared to Example 1. The use of oxidized carbon black according to the present invention (Example 3) significantly improves these mechanical properties compared to conventional acid-functionalized oxidized carbon black without adversely affecting the bound rubber.

[0101] Therefore, the cured rubber composition incorporating the oxidized carbon black according to the present invention (Example 3) exhibits mechanical properties that more closely reflect those achieved with the corresponding unoxidized reference carbon black (Example 1), while showing significantly improved hysteresis properties, as suggested by the increase in binding rubber. Furthermore, the cured rubber composition containing the oxidized carbon black of the present invention (Example 3) exhibits superior tear resistance compared to Comparative Examples 1 and 2.

[0102] Preparation of vulcanizable rubber compositions with modified accelerator content (Examples 4-6) Furthermore, vulcanizable rubber compositions with the formulations shown in Table 4 were prepared using bead-shaped carbon blacks A to C, and the amount of N,N-diphenylguanidine (DPG) vulcanization accelerator was systematically varied.

[0103] Examples 1-3 were prepared as described above, except that TDAE was not used and a DPG accelerator (if any) was added to the rubber mixture along with sulfur and TBBS-80 components, respectively. Each of Examples 4-6 involved the preparation of a series of four curable rubber compositions with different amounts of DPG accelerator, which varied from 0 phr (variable a) to 0.5 phr (variable b), 1.0 phr (variable c), and 2.0 phr (variable d), as shown in Table 4.

[0104] [Table 4]

[0105] Curing of vulcanizable rubber composition The vulcanizable rubber compositions according to Examples 4-6(a)-(d) were each cured in a curing press at 160°C for 60 minutes. The applied pressure was 120-150 bar.

[0106] Following the curing of the rubber composition, the change in torque with respect to curing time was measured using a moving direometer (MDR2000E) in accordance with ISO 6502-3:2018. The measurement data are plotted in Figure 1 to show the different curing characteristics of the rubber composition.

[0107] In the torque vs. time plot, the time to reach the maximum torque is "time to harden," t 100 This is considered to be the case. The time t reported as an indicator of hardening in Table 5 below 95 These correspond to the rising torque gradient in the torque-time plot, respectively, and the corresponding t 100 This corresponds to the time it takes to reach 95% of the torque value achieved.

[0108] Each time t 95 The rubber compositions cured during the following timeframes (rounded up to the next integer in minutes, see Table 5 below) were tested for their properties as follows:

[0109] Mooney viscosity, hardness, modulus of elasticity, elongation at break, and tear resistance were measured for Examples 1 to 3 as described above.

[0110] Furthermore, the loss coefficient tanδ and complex modulus E* were measured in accordance with DIN53 513, in strain control mode (1 ± 0.5 mm), for cylindrical specimens (10 mm in height and 10 mm in diameter), at 60°C and a frequency of 16 Hz.

[0111] Ball rebound was further measured according to the test method based on ASTM3574, and DIN ISO8307 was performed as follows: A cylindrical test specimen with a diameter of 35 mm and a height of 19 mm was heated to 60 ± 0.2 °C. The circular regions of the test specimen were ensured to be smooth and parallel to each other. A steel ball with a diameter of 19 mm was dropped from a height of 500 mm through a drop tube into one of the circular regions of the test specimen. The height corresponds to the distance between the lowest point of the steel ball and the point of impact on the test specimen. The time interval between the first and second impacts of the steel ball on the test specimen was measured by a light barrier located near the point of impact on the test specimen. The time resolution of the light barrier was 10⁻¹⁰ -4 The value was s. The time interval measured in 5 experiments per test sample was averaged and applied to calculate the rebound height. Then, the rebound height was used again to calculate the ball rebound corresponding to the percentage ratio of rebound height to drop height.

[0112] The results obtained are summarized in Table 5.

[0113] [Table 5]

[0114] Figure 1 and Table 5 t 95 This demonstrates that the rubber compositions containing oxidized carbon black according to the present invention (Examples 6a-d) vulcanize significantly faster than conventional rubber compositions containing oxidized carbon black containing the same amount of DPG accelerator (Examples 6a-d). The rubber compositions containing oxidized carbon black according to the present invention (Examples 6a-d) actually achieve a curing rate equivalent (e.g., t) to the corresponding rubber compositions containing unoxidized reference carbon black (Examples 4a-d). 95Therefore, using the carbon black oxide according to the present invention allows vulcanization within a commercially reasonable time with relatively small amounts of DPG accelerators or even without DPG accelerators, compared to conventional carbon black oxide, thus minimizing or avoiding the use of potentially harmful and expensive accelerator substances, such as DPG. Furthermore, as shown by the data in Table 5, the carbon black oxide according to the present invention, like conventional carbon black oxide, does not have the significantly slow curing drawback associated with the use of conventional carbon black oxide, although it imparts improved hysteresis properties to the rubber composition, as evidenced by a reduced loss coefficient tanδ and increased ball rebound force compared to the corresponding unoxidized reference carbon black in Table 5. As evidenced by the data in Table 5, rubber compositions incorporating the carbon black oxide according to the present invention exhibit even more acceptable mechanical properties, and tear resistance is further improved compared to the corresponding rubber composition incorporating the reference black.

Claims

1. A solid carbon black material comprising carbon black oxide having a pH of 7.5 or more as measured according to ASTM D1512-15b test method B - Sonic slurry.

2. The solid carbon black material according to claim 1, wherein the carbon black oxide has a pH of at least 8 as measured according to ASTM D1512-15b test method B - Sonic slurry.

3. The carbon black oxide has a volatile content of more than 1.0% by weight based on the total weight of the carbon black oxide as measured by thermogravimetric analysis at 950 °C, and / or has an oxygen content of at least 0.5% by weight based on the total weight of the carbon black oxide as measured by elemental analysis. The solid carbon black material according to claim 1 or 2.

4. The solid carbon black material according to any one of claims 1 to 3, wherein the carbon black oxide is ozone oxidized carbon black and / or oxidized furnace black.

5. The solid carbon black material according to any one of claims 1 to 4, wherein the carbon black oxide contains carboxylate groups in an amount of at least 100 μmol / g.

6. The solid carbon black material according to any one of claims 1 to 5, wherein the carbon black oxide having a pH of 7.5 or more has less than 20 μmol / g of carboxylic acid groups.

7. The solid carbon black material according to any one of claims 1 to 6, wherein the solid carbon black material is in the form of powder or beads.

8. The solid carbon black material according to any one of claims 1 to 7, wherein the carbon black oxide has one or more or all of the following: (a) A statistical thickness surface area measured according to ASTM D6556-17 in the range of 30 to 500 m 2 / g; (b) A BET surface area measured according to ASTM D6556-17 in the range of 50 to 500 m² / g; 2 (c) An oil absorption amount (OAN) measured according to ASTM D2414-18 in the range of 50 to 150 mL / 100 g; (d) An oil absorption amount (COAN) of the compressed sample measured according to ASTM D3493-18 in the range of 50 to 150 mL / 100 g; (e) An iodine adsorption amount measured according to ASTM D1510-19 in the range of 20 to 300 mg / g.

9. The solid carbon black material according to any one of claims 1 to 8, wherein the solid carbon black material consists of oxidized carbon black having a pH of 7.5 or more as measured according to ASTM D1512-15b test method B - Sonix slurry.

10. A method for producing the solid carbon black material according to any one of claims 1 to 9, the production method including the following: (i) Providing oxidized carbon black, (ii) Treating the oxidized carbon black with a base, (iii) Optionally, wet beadizing the oxidized carbon black.

11. The method for producing a solid carbon black material according to claim 10, wherein the base is used in at least an equimolar amount with respect to the acidic groups in the oxidized carbon black.

12. (i) A polymer component, and (ii) The solid carbon black material according to any one of claims 1 to 9, A composition containing the same.

13. The composition according to claim 12, wherein the polymer component comprises natural rubber, emulsion - styrene - butadiene rubber, solution - styrene - butadiene rubber, polybutadiene, polyisoprene, ethylene - propylene - diene rubber EPDM, ethylene - propylene rubber EPM, halogenated butyl rubber, butyl rubber, chlorinated polyethylene, chlorosulfonated polyethylene, acrylonitrile - butadiene rubber, hydrogenated acrylonitrile - butadiene rubber, polychloroprene, acrylate rubber, ethylene - vinyl acetate rubber, ethylene - acrylic rubber, epichlorohydrin rubber, silicone rubber, fluorosilicone rubber, fluorocarbon rubber, or a mixture of any combination thereof.

14. The composition according to claim 13, further comprising one or more additives selected from vulcanizing agents, accelerators, activators, processing additives, resins, softeners, pigments, waxes, peptizers, and antioxidants.

15. The composition according to claim 13 or 14, substantially free of guanidine - type accelerators.

16. The composition according to claim 12, further comprising water and / or one or more organic solvents.

17. The composition according to claim 16, wherein the composition is a liquid composition.

18. The composition according to any one of claims 12 to 17, wherein the composition comprises a solid carbon black material in an amount of 1 to 100 parts by weight per 100 parts by weight of the polymer component.

19. An article prepared from the composition according to any one of claims 12 to 18.

20. The article according to claim 19, which is a tire, a tire component, a cable sheath, a tube, a drive belt, a conveyor belt, a roll cover, a shoe sole, a seal member, a profile, a damping element, a coating, or a colored or printed article.

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