Filler composition

Abstract

A filler composition is proposed which comprises or consists of (a) acetylene black, (b) zinc and / or a zinc compound, and optionally (c) ash.

Description

Field of the Invention

[0001] The present invention relates to the field of industrial fillers, in particular to the tire industry, and relates to a filler composition containing acetylene black and having improved vulcanization properties, a method for obtaining such a composition, and various related applications. Background Art

[0002] In tire technology, curing refers to the process of applying pressure to a green tire in a mold to shape it and applying heat energy to promote chemical reactions between the rubber compound and other materials. The green tire is automatically transferred to the lower mold bead seat, a rubber bladder is inserted into the green tire, the mold is closed, and at the same time the rubber bladder expands. As the mold closes and locks, the pressure of the rubber bladder increases, filling the green tire with the mold and presenting the tread pattern and sidewall lettering engraved on the mold. The rubber bladder is filled with a circulating heat transfer medium, such as steam, hot water, or an inert gas. At the end of curing, the pressure is released, the mold is opened, and the tire is demolded from the mold.

[0003] Acetylene black is a useful component for vulcanizing rubber bladder compounds because it has a higher degree of graphitization and higher thermal conductivity than furnace black at similar dosages. This property accelerates the vulcanization process of the green tire, shortens the vulcanization time, increases the output per vulcanization unit, and reduces the energy consumption of the tire factory.

[0004] To obtain carbon black, acetylene is partially burned in furnace units operating in parallel. Acetylene thermally decomposes at extremely high temperatures in each furnace. Thereafter, the combustion gases and acetylene black are separated, concentrated, and transported to a bag filter system. Compared with standard furnace black in the carbon black market, acetylene black is convincing with its excellent properties of high purity and almost no impurities. These advantages stem from acetylene as a pure raw material and its thermal decomposition at extremely high temperatures.

[0005] The service life of traditional tires is from 1 to about 10 years, while the service life of bladders is much shorter. Due to the short service life of bladders and the typical bladder composition containing about 50 phr or 30 wt% of acetylene black, vulcanized bladders become an ideal source for recovering acetylene black. Related prior art

[0006] The pyrolysis of waste tires and tire carcasses has long been prior art and there are a large number of patents disclosed, such as:

[0007] EP 0287534 B1 (MARANGONI) provides a system including a pyrolysis chamber having an inlet for a tire carcass and communicating with at least one duct for supplying combustion air. The pyrolysis chamber also communicates with a steam generator and has a frustoconical fixed bottom communicating coaxially with the combustion air duct. In addition, a rotary arm member is provided and connected to the fixed bottom for discharging unburned waste materials from an outlet formed through the fixed bottom.

[0008] EP 0592057 B1 (FORMEX) discloses an apparatus and method for reprocessing shredded organic waste (such as rubber waste from worn automobile tires) by pyrolysis. The method includes: pyrolyzing the shredded waste in a pyrolysis tank into a mixture containing volatile components, liquid components and solid components, where the pyrolysis tank is a bed or a bath with a temperature range of 450 to 550 °C; collecting at least a part of the volatile components from the gas space above the pyrolysis tank and conveying the collected volatile components out of the pyrolysis tank for further utilization; and introducing gas into the gas space above the pyrolysis tank intermittently or continuously.

[0009] EP 0768345 B1 (MITUBISHI) provides a method and apparatus for producing carbon black. In this method, a gasifier is separated into a lower gasification section and an upper pyrolysis section by a distribution plate. Waste tire fragments are fed into the pyrolysis section of the gasifier and pyrolyzed to separate them into pyrolysis gas and fixed carbon. Fine fixed carbon is separated from the mixed gas discharged from the gasifier and fed into the gasification section of the gasifier to generate gasification gas. The gasification gas is fed to the pyrolysis section through the distribution plate. After separating the fine fixed carbon, a mixed gas of pyrolysis gas and gasification gas is introduced, thereby producing carbon black.

[0010] EP 1114122 B1 (SES) relates to a method for recovering a combination of carbon and hydrocarbons from waste tires or similar polymer materials by pyrolysis. The method uses a reactor in which the materials are placed in a mostly fragmented form. Thus, the materials are heated to the pyrolysis temperature by recycling previously formed and heated pyrolysis gas, which is guided through the materials, and the pyrolysis gas obtained in this way is condensed into a condensable product in a condenser connected to the reactor.

[0011] EP 1163092 B1 (METSO) claims a process and system for recovering desired constituent materials from automobile tire fragments by pyrolysis. The system includes a pyrolysis section divided into a plurality of independent heating zones.

[0012] EP 1785248 B1 (KRIVORUCHKO) relates to the heat treatment of hydrocarbon raw materials, particularly the recycling of waste tires, and the method can improve the efficiency of hydrocarbon material treatment and reduce energy costs. The method includes pyrolyzing shredded tires at a temperature of 550 to 800 °C in a reducing gas medium, accompanied by the separation of pyrolysis products.

[0013] For example, WO 2015 128278 A1 (ORION) discloses a granular acetylene black having a mass strength of at most 200 N as measured according to ASTM D1937 - 10 and an average granular size of at least 1.0 mm as measured according to ASTM D 1511 - 10, and also discloses the use of any of the said granular acetylene blacks in producing a rubber compound comprising a resin or polymer or rubber matrix and acetylene black dispersed in the matrix, as well as a method for producing such a rubber compound. Object of the invention

[0014] An object of the present invention is to provide an acetylene black composition recovered from a vulcanized capsule rubber compound, which exhibits at least similar, preferably even better, vulcanization properties, particularly in terms of thermal conductivity and vulcanization time.

[0015] Another object of the present invention is to develop a method for recovering acetylene black from a vulcanized capsule containing acetylene black, which is sustainable, particularly compared to producing acetylene black from acetylene, and the recovery method emits less carbon dioxide, and the by - products provide additional environmental benefits. Summary of the Invention

[0016] The first task of the present invention relates to a filler composition comprising or consisting of: (a) acetylene black, (b) zinc and / or zinc compounds, and optionally (c) ash.

[0017] Ash is generally the residue after the treatment of a substance in a high - temperature oxygen - containing atmosphere, or in other words, the content of inorganic non - combustible substances in a sample. For example, carbon black can be tested according to the method of ASTM D 1506 - 2015.

[0018] A feature of the present invention is that the filler composition contains zinc, which is a component present in all vulcanized capsules. Zinc can exist in the form of metallic zinc. Alternatively, zinc compounds can also be contained, and the compounds are selected from zinc oxide, zinc complexes and coordination compounds, aggregates of zinc and coke particles, and mixtures thereof. Zinc can also be contained in the ash, for example, in the form of zinc compounds. The zinc compounds can also contain a certain amount of metallic zinc, for example, as a residue in the manufacturing process.

[0019] In fact, in order to shorten the vulcanization time, acetylene black and zinc compounds, preferably ZnO, are usually used in the production of capsules. However, surprisingly, the applicant has found that, with the same amounts of acetylene black and zinc and / or zinc compounds, the filler composition according to the present invention significantly shortens the vulcanization time more than the mixtures containing carbon black and zinc components in the prior art, respectively.

[0020] Another advantage of the present invention is that, compared with similar compositions, the filler composition has improved thermal conductivity and fewer defects.

[0021] This should be understood as the inhomogeneity of the composition, which will reduce the product quality. In fact, the filler composition according to the present invention can be used without further reprocessing, and can be easily replaced with fresh acetylene black if the weight is equal to the proportion of acetylene black in the filler composition.

[0022] Compared with the production of fresh carbon black, this production process also has the characteristic of reduced carbon dioxide emissions. In addition, the gas mixture generated during the pyrolysis process can be used to generate energy, thereby driving the pyrolysis furnace. Compared with other pyrolysis processes, especially the pyrolysis of waste tires, the gas obtained by this process contains significantly more hydrogen and less methane, and thus has a higher calorific value. Filler composition

[0023] In a preferred embodiment, the filler composition consists of the following components: (a) about 60 to about 99.5% by weight, preferably about 75 to about 99.5% by weight, more preferably about 85 to about 99.5% by weight of acetylene black; (b) about 0.2 to about 10% by weight, preferably about 0.4 to about 8% by weight of said zinc and / or zinc compounds, and optionally (c) about 0.5 to about 15% by weight, preferably about 1 to about 12% by weight of ash, provided that the sum of the above contents is 100% by weight. For the sake of easy understanding, it should be emphasized that the present invention does not cover compositions with a content exceeding 100% by weight or less than 100% by weight. According to the information provided in the specification, a person skilled in the art can easily identify a composition with a total weight of 100% without further investigation.

[0024] For the purposes of the present invention, the term "ash" refers to solid pyrolysis and / or coking products different from carbon black, especially various salts. The zinc compounds may be selected from metallic zinc, zinc oxide, complexes and coordination compounds of zinc, aggregates of zinc and coke particles, and mixtures thereof.

[0025] In another preferred embodiment, the composition has the following specific surface area and filler structure: - about 25 to about 200 m2 a BET surface area of / g; and / or - an OAN of from about 80 to about 400 ml / 100 g. Wherein, the BET surface area is determined according to ASTM D 6556-2021, and the oil absorption number (OAN) is determined according to ASTM D2414-2022.

[0026] In another preferred embodiment, the filler composition consists of a ground material having a particle size not greater than 15 μm. The particle size is analyzed by laser diffraction according to ISO 13320:2020.

[0027] The present invention also relates to a filler composition obtainable or obtained by the following steps: (a) Providing a vulcanized capsule; (b) Pyrolyzing the capsule to obtain a product mixture consisting of a solid residue, oil and gas fractions; (c) Removing oil and gas phase from the solid residue; and (d) Grinding and / or granulating the solid residue. Manufacturing process

[0028] The present invention also relates to a method for manufacturing a filler composition, the method comprising the following steps or consisting of the following steps: (a) Providing a vulcanized capsule containing acetylene black; (b) Pyrolyzing the capsule to obtain a product mixture consisting of a solid residue, oil and gas fractions; (c) Removing oil and gas from the solid residue; and (d) Grinding and / or granulating the solid residue in step (c).

[0029] The thermal decomposition of organic matter under anaerobic conditions is called pyrolysis. During pyrolysis, polymer chains and crosslinking bonds break and decompose into shorter fragments. These fragments can then be reorganized according to the chemical composition and structure of the molecules. The main gases emitted are CO2, CO, H2, CH4 and various hydrocarbons. In addition to the remaining solid residue, a mixture of oil vapors is also formed. The condensable fraction appears as pyrolysis oil, while the non-condensable fraction exists as pyrolysis gas. Thus, three substances are formed: pyrolysis coke, pyrolysis oil and pyrolysis gas. The process temperature and heating rate play a decisive role in their composition and distribution.

[0030] The thermal decomposition of rubber materials usually starts at a temperature of 270 °C. During pyrolysis, the polymer chains break and decompose into shorter fragments; random fragmentation occurs upon heating. Fragments of variable average length are formed, and the length decreases with increasing temperature. At low temperatures, kerosene, olefins, and aromatics are mainly formed. In contrast, at higher temperatures, light oils and gases such as hydrogen, methane, and heavy hydrocarbons are formed. Since carbon black is used in most rubber compounds, solid residues are formed even upon complete decomposition. Higher decomposition temperatures favor the formation of pyrolysis gases while the oil yield decreases. The product distribution changes with increasing temperature and heating rate, favoring an increase in gas yield and hydrogen concentration. For detailed information on the pyrolysis process, see EP 2427533 B1 and EP 2661475 B1 (both assigned to PYRUM INNOVATIONS).

[0031] That being said, pyrolysis is preferably carried out at a temperature of about 300 to about 1000 °C, more preferably about 400 to about 650 °C. The temperature is preferably increased at a rate of 100 °C / 15 minutes until the maximum temperature is reached. Usually, pyrolysis is completed after 30 to 100 minutes, but it is recommended to continue the process at the high temperature for 100 to 250 minutes to ensure that all volatile substances have been removed. The solid residue can be separated from the pyrolysis oil, for example, by filtration, followed by washing and drying steps. The pyrolysis gas is introduced into a furnace and burned to generate energy for heating the pyrolysis furnace. Industrial applicability

[0032] Another object of the present invention relates to a rubber compound comprising or consisting of: (a) at least one synthetic and / or natural vulcanizable rubber or polymer; and (b) a filler composition as described above.

[0033] In a first preferred embodiment, the rubber compound exhibits - a thermal conductivity of about 0.15 to about 0.5, preferably about 0.15 to about 0.4, more preferably about 0.2 to about 0.375 W / (m*K) at 25 or 150 °C. - The thermal conductivity should be determined according to ASTM E 1461-2011.

[0034] In another preferred embodiment, the stock shows a surface topography (TOPO) of less than 2% of the cut specimens, more preferably from 0.2% to 1.5%, and most preferably from 0.1% to 1.4%. TOPO is a measure of filler dispersion determined by surface topography, including the Medalia correction. For the specific method, see "Filler Dispersion Analysis by Topography Measurements" by A. Wehmeier, Technical Report TR 820, Degussa GmbH, and "Entwicklung eines Verfahrens zur Charakterisierung der Füllstoffdispersion in Gummimischungen mittels einer Oberflächentopographie" by A. Wehmeier, Thesis, 1998 at the Münster University of Applied Sciences, and DE 199 17975 C2.

[0035] The present invention also relates to a method for shortening the vulcanization time during the production of rubber, tire, and / or vulcanized bladder stocks, which method comprises the following steps or consists of the following steps: (a) providing a curable rubber or a curable rubber blend or polymer; (b) adding a filler composition as defined above; (c) vulcanizing the mixture of step (b); and optionally (d) vulcanizing a bladder or other rubber article. Curable rubbers and polymers

[0036] The term "curable rubber composition" refers to a composition in which the rubber component is optionally combined with various other ingredients conventionally used in the rubber compounding field, and which can be vulcanized by a vulcanization reaction to form a vulcanized rubber. Unless otherwise specified, the terms "curable" and "vulcanizable" are used interchangeably in this specification and both refer to a chemical reaction in which polymer chains are linked to each other by a crosslinking agent or a vulcanizing agent.

[0037] The vulcanizable rubber component suitable for a vulcanizable rubber composition may comprise one or more rubbers containing olefinic unsaturated bonds, namely diene rubbers or elastomers. Unless otherwise specified, the terms "rubber" and "elastomer" are used interchangeably in this specification. The rubber component may also comprise a mixture of a rubber containing olefinic unsaturated bonds and other polymeric materials without such unsaturated bonds, such as thermoplastic or thermosetting polymers, etc. However, preferably, the rubber component comprises only one or more rubbers containing olefinic unsaturated bonds. The phrases "rubber containing olefinic unsaturated bonds" and "diene rubber" are used interchangeably and are intended to include natural rubber, synthetic rubber, or mixtures thereof.

[0038] Natural rubber can be used in its raw form or in various processed forms conventionally known in the rubber processing field. The synthetic diene rubber can be any rubber containing at least one diene monomer alone or a rubber formed by a diene monomer together with other monomers, but is not limited thereto. Exemplary diene rubber materials suitable for the practice 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 monomer rubber (EPDM), butyl rubber and halogenated butyl rubber, acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, polychloroprene, or any combination thereof. The rubber composition according to the present invention may also comprise one or more non-diene rubber materials. Exemplary non-diene rubber materials suitable for the practice 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, or any combination thereof. Suitable rubbers also include functionalized rubbers and rubbers coupled with silicon or tin. For example, the rubber can be functionalized with functional groups such as amines, alkoxys, silyls, thiols, thioesters, thioethers, thioalkyls, mercaptans, sulfides, or combinations thereof. The one or more functional groups can be primary, secondary, or tertiary functional groups and can be located at one or both ends of the chain (e.g., α, ω-functionalized), on the side chains of the polymer backbone, and / or within the polymer backbone chain. The rubber according to the present invention can also be partially crosslinked. Thus, before being used in a vulcanizable rubber composition, some of the polymer chains of the rubber material can be crosslinked with or without a coupling agent. The polymeric material can also be supplied in any form, but is usually supplied in bales or pieces.

[0039] Preferably, the rubber component comprises a mixture of natural and synthetic diene rubbers. Non-limiting specific rubber materials that can be used in the practice of the present invention are, for example, Butyl 301 and 110.

[0040] The curable rubber composition may comprise the filler composition according to the present invention in an amount of 5 to 100 phr, for example 10 to 70 phr. As used herein, the term "phr" refers to the number of parts by weight of the respective material per 100 parts by weight of rubber or elastomer.

[0041] The curable rubber composition according to the present invention may optionally further comprise at least one vulcanizing agent capable of inducing rubber curing. Possible vulcanizing agents include any vulcanizing agent known in the art, such as phenolic resins.

[0042] The curable rubber composition may also comprise one or more other fillers, such as other carbon blacks, silica, organosilicas, carbon nanotubes, carbon fibers, graphite, metal fibers, etc. Carbon blacks useful in this regard may be exemplified by ASTM grades of carbon blacks selected from series 100 to series 900 according to ASTM D1765. For curing bladders, acetylene black is strongly recommended instead of furnace black. Acetylene black can improve the heat conductivity of the rubber compound.

[0043] The curable rubber composition according to the present invention may also comprise other commonly known additives. Such additives include, for example, vulcanization aids such as primary vulcanization accelerators and secondary vulcanization accelerators, activators and prevulcanization inhibitors; processing additives such as oils; resins and plasticizers in the form of tackifying resins; softeners; fillers; waxes; peptizers; and anti-aging agents such as antioxidants and antiozonants. Examples of primary vulcanization accelerators and secondary vulcanization accelerators that can be used include, for example, guanidines, dicarbamates, dithiocarbamates, thiurams, thioureas, 2-mercaptobenzothiazoles, benzothiazole sulfonamides, aldehyde amines, amines, disulfides, thiazoles, xanthates, and sulfenamides. Specific examples may refer to, for example, N-tert-butyl-2-benzothiazolesulfenamide commercially available from Rhein Chemie Additives under the trade name Rhenogran TBBS-80, and diphenylguanidine commercially available from Rhein Chemie Additives under the trade name Rhenogran DPG-80. Suitable activators include combinations of zinc oxide and fatty acids such as stearic acid, lauric acid, palmitic acid, oleic acid, or naphthenic acid. The total amount of the primary accelerator in the composition ranges from 0.05 to 4 phr. The amount of the secondary accelerator is usually less than that of the primary accelerator, and its amount in the composition ranges from 0.05 to 3 phr.

[0044] Other rubber compounds may be resins cured in the same way as the formulations in the experimental section herein. A typical resin based on octylphenol and formaldehyde for curing butyl rubber is SP 1045 from Safic-Alcan.

[0045] The filler composition according to the present invention can advantageously be used for producing a rubber compound comprising a polymer matrix in which acetylene black is dispersed. Besides rubbers and elastomers, other organic resins and polymers can be used as the matrix. Of course, the vulcanized rubbers and elastomers are particularly suitable for manufacturing end products such as tires and vulcanized capsules.

[0046] The filler composition according to the present invention can be compounded and dispersed in the above-mentioned resin, polymer or rubber matrix using standard mixers and blenders, and can also be heated to facilitate uniform dispersion if permitted by the choice of the resin, polymer or rubber system, wherein blenders, mixers, kneaders or single-screw or twin-screw extruders known to those skilled in the art can be used. Additional uses

[0047] The filler composition according to the present invention, optionally after grinding, granulating or pelletizing, acts in a polymer or rubber, imparting conductivity and thermal conductivity thereto. Therefore, the composition can also be used as a conductive agent for batteries (such as disposable batteries, storage batteries, fuel cells or compensators). It can also be used as an antistatic agent or a conductive agent for conductive paper. The filler composition according to the present invention is particularly suitable for producing semiconductor shielding layers for wire and cable applications. In addition, it can also be advantageously used in coating applications. Therefore, another object of the present invention relates to the application of the filler composition as an additive in the production of: - batteries; - adhesives and sealants; and - conductive rubber compounds, wires and cables.

[0048] The method can include the step of plasticizing a vulcanizable polymer rubber compound, for example, by stirring, before mixing the vulcanizable rubber compound with the filler composition. For this purpose, the vulcanizable rubber compound can be placed in a suitable instrument (such as an internal mixer) and stirred for 2 minutes or less, for example, 1 minute or less, for example, 45 seconds. Subsequently, the filler composition and other optional components can be added to the plasticized vulcanizable rubber compound and mixed together as described above.

[0049] Mixing can be carried out using techniques and instruments conventionally known in the rubber processing field. Mixing can be achieved, for example, by mixers, stirrers, mills, kneaders, ultrasonic machines, dissolvers, shaking mixers, rotor-stator dispersion assemblies, high-pressure homogenizers or combinations thereof. Mixers with an intermeshing or tangential rotor structure are preferably used.

[0050] If necessary, mixing can include heating the components of the mixture to a temperature above room temperature. However, preferably, no additional heat is provided to the mixture during the mixing process except for the heat generated by the stirring process itself.

[0051] After the first mixing step, the resulting mixture can be immediately subjected to the second mixing step or can be stored between the two mixing steps. For example, the mixture can be left standing for a few minutes to several months, such as at least 60 minutes or at least 12 hours. Before the second mixing step, the mixture can be transferred to another mixing chamber and / or another location, such as to a customer.

[0052] After the first mixing step or, if present, the second mixing step, the method for preparing a vulcanizable rubber composition preferably further comprises the steps of: adding a vulcanizing agent, and, if desired, one or more activators, one or more accelerators, and other components conventionally used in the rubber compounding field as described above, to the mixture. Subsequently, the composition is preferably mechanically agitated to effect at least partial mixing of the composition, or preferably complete mixing. The mixing is generally carried out between 10 °C and 140 °C, more usually between 80 °C and 120 °C, and is carried out with constant agitation for less than 5 minutes, such as less than 3 minutes. Conditions can be selected, especially the rotor speed, such that the temperature of the mixture containing the curing agent remains below 110 °C.

[0053] In addition, the vulcanizing agent can optionally be added to an open two-roll mill instead of to an internal mixer.

[0054] The present invention will be described in more detail in the following examples. Specifically, the methods for measuring the specific acetylene black properties defined above and in the claims will be given in the experimental section below. Examples _____________________________________________________________________ Example 1 Pyrolysis of the vulcanization capsule

[0055] To obtain the raw material for pyrolysis, a vulcanization capsule model compound was prepared using the formulation in Table 1. The rubber compound was mixed using a two-step mixing process. A GK1.5E mixer from Werner and Pfleiderer was used, with a mixing chamber volume of 1.58 liters and equipped with intermeshing mixing rotors. The rotor speed was 45 rpm and the mixing chamber temperature was 60 °C. Table 1 Capsule compound Composition of the capsule compound Dosage (phr) Butyl 301 95 Baypren 110 5 Acetylene black 50 ZnO 5 Process oil P 100 5 SP 1045 9 In the rubber chemical industry, the parts per hundred rubber (phr) refers to the mass parts of each component in an elastomer compound formulation. These numbers are calculated based on 100 (mass) parts of the base polymer or base polymers (in the case of polymer blends).

[0056] Component information: ·Butyl 301 (isobutylene-isoprene rubber, IIR) and Baypren 110 (chloroprene rubber, CR), purchased from Arlanxeo Deutschland GmbH. ·Acetylene black was Y200 BDS, purchased from Orion Engineered Carbons GmbH. ·Process oil P 100, purchased from Schill and Seillacher. ·ZnO, purchased from Arnsperger Chemicals GmbH. ·SP-1045 octylphenol novolac resin-based curing resin, purchased from Safi-Alcan.

[0057] The chloroprene rubber and butyl rubber were kneaded for 1 minute, and 35 phr of filler was added. After 90 seconds, the ram was lifted and purged, and the remaining 15 phr of CB and process oil were added, and kneading continued for 90 seconds. After lifting the ram and purging again, kneading continued for 90 seconds. Thereafter, the stock was poured onto a two-roll mill, cooled, and sheeted. Ensure that the kneading temperature does not exceed 160 °C.

[0058] The stock was left standing overnight, and then the phenolic resin SP-1045 was added to the mixture on a two-roll mill. The mixing temperature was controlled below 110 °C.

[0059] Then the 2-mm-thick rubber sheet was cured at 190 °C for 30 minutes. Then the rubber sheet was shredded into small pieces about 1 to 5 mm in size ( Figure 1 ), for pyrolysis operation.

[0060] The pyrolysis experiment was carried out in laboratory equipment with a reactor volume of 1 liter and a heating power of 1 kW el . The material was placed in a pyrolysis reactor as disclosed in, for example, EP 2427533 B1 and inerted together with the equipment components. Subsequently, the material was slowly heated to the target temperature, causing the material to decompose slowly. Before the experiment started, a quantified amount of rubber particles was added to the reactor, and after connection, nitrogen from a pressurized gas cylinder was used to inert all the pipes. For this purpose, nitrogen was first added and then discharged through a ball valve. The experiment started with heating the reactor. The temperature of the insulated reactor was increased and maintained at a set value by a heating coil controlled by a temperature sensor inside the reactor. The pyrolysis gas released during pyrolysis was cooled to 5 °C in a heat exchanger. During this process, the part with a sufficiently low vapor pressure would condense out and precipitate as pyrolysis oil in a laboratory flask. The uncondensed part of the pyrolysis gas was sucked in through a fume hood and passed through a coalescing filter to remove any aerosol.

[0061] Before the test began, the material was added to the reactor for a basic test, and then the reactor was heated together with the sample material. The target temperature for pyrolysis was 650 °C and it was held for 1 hour. Figure 2 Figure 2 shows the overall process of the basic experiment, where the applied reactor temperature and the required core temperature were considered. The starting material was fed into the cold reactor, and after inerting, it was continuously heated to the target temperature of 650 °C. For this purpose, the target temperature of the pyrolysis reactor was determined. The selected reactor target temperature for this was 670 °C. After reaching the target temperature, it was maintained for 1 hour to ensure the completion of the pyrolysis reaction.

[0062] Figure 3 shows the temperature profiles of the core temperature and the outlet gas (before being cooled by the heat exchanger) as well as the variation of pressure over time. It can be seen from the figure that the core temperature and the gas temperature increase simultaneously, indicating the early start of thermal decomposition. It should be noted that when heating, the temperature of the material near the reactor wall is always higher than the core temperature. Visible white mist formation was observed when the core temperature was 33 °C and the wall temperature was 109 °C, which was partly due to the evaporation of water. Condensation of pyrolysis oil was observed when the core temperature was 61 °C and the wall temperature was 220 °C.

[0063] With further heating, the temperature of the evolved gas continued to rise until it reached a maximum of 139 °C after a total of 49 minutes, at which time the core temperature was 363 °C. Subsequently, after the material temperature reached 650 °C, the gas temperature dropped to 60 °C and remained constant until the reactor heater was turned off. The drop in the gas temperature indicates that the pyrolysis reaction is about to be completed. After the material temperature reached 650 °C, it was held for 1 hour to remove volatile substances and the oil residues adsorbed in the pyrolysis coke, ensuring complete pyrolysis. During the entire test, the reactor pressure remained almost constant. Only a slight increase from 3 mbar to 5 mbar was observed during the oil condensation process. The pressure rose to 112 mbar after 180 minutes, which was due to the introduction of the nitrogen purge system. Table 2 shows the relevant mass balance of the tests conducted. The proportion of pyrolysis gas was determined by calculation. Table 2 Mass balance of the test series

[0064] Most of the rubber compound was converted into pyrolysis gas, with an average proportion of 44.4%. The solid residue ("pyrolysis coke") accounted for the second largest share, with an average proportion of 37.1%. The formation of pyrolysis oil accounted for an average of 18.6%.

[0065] The obtained solid residue was in the form of a black porous solid, containing acetylene black, ash, zinc, and coking products ( Figure 4)。This substance has good fluidity and can be easily removed from the reactor. All the tested solid residues were combined to make a representative sample, which was then ground in an impact mill to avoid particles with a diameter greater than 15 μm.

[0066] Table 3 shows the particle size measurement results of the ground solid residues. The grinding yield was 52%. A total of 390 grams of ground solid residues were obtained. The average particle size distribution is as Figure 5 shown. Table 3 Particle size distribution of the ground solid residues. Particle size was analyzed by laser diffraction according to ISO 13320:2020. Batch <![CDATA[D x (10)]]> <![CDATA[D x (50)]]> <![CDATA[D x (90)]]> <![CDATA[D x (95)]]> <![CDATA[D x (97)]]> A 0.39 1.54 9.73 12.2 13.9 B 0.40 1.60 9.23 11.5 12.9 C 0.41 1.64 9.36 11.7 13.1 Average value 0.40 1.59 9.46 11.8 13.3

[0067] The obtained pyrolysis oil is a dark brown, low-viscosity liquid with a pungent sulfur-like odor. After standing for a long time, a second phase of a colorless transparent liquid was observed. This is most likely process water, which is usually formed during the pyrolysis of rubber.

[0068] From the composition of the pyrolysis gas, hydrogen is clearly the main component, with an average proportion of 42.6 vol%. The second most abundant component is methane, accounting for 16.7 vol%. Followed by nitrogen, accounting for 5.7 vol%. The proportions of oxygen, carbon monoxide, and carbon dioxide are all less than 2 vol%. Compared with the gas composition of the pyrolysis gas during the conversion of waste tires, the hydrogen content is significantly higher, and thus the calorific value is correspondingly higher. Analysis data of the sample material

[0069] The properties of the sample material (also known as the filler composition, recycled acetylene black, or rAB) according to the present invention are summarized in Table 4: Table 4 Properties of recycled acetylene black (rAB) Property Unit rAB1 BET surface area (ASTM D-6556-19a) <![CDATA[m 2 / g]]> 43 STSA surface area (ASTM D-6556-19a) <![CDATA[m 2 / g]]> 40 OAN (ASTM D-2414-21) ml / 100g 138 Toluene permeability [425 nm] (ASTM D1618-18) ％ 95.8 pH-value (ASTM 1512-21) 7.01 Ash content (ASTM D 1506:2015) Weight % 7.89 Carbon (DIN 51732:2014-07) Weight % 91.03 Hydrogen (DIN 51732:2014-07) Weight % 0.38 Nitrogen (DIN 51732:2014-07) Weight % 0.09 Sulfur (DIN 51732:2014-07) Weight % 0.03 Zinc (ASTM D8371-20) Weight % 5.9 Performance measurement The BET surface area was measured according to ASTM D-6556-19a standard. The STSA specific surface area was measured according to ASTM D-6556-19a standard. The OAN structure was measured according to ASTM D-2414-21 standard. The toluene transmittance [425 nm] was measured according to ASTM D1618-18 standard. The pH-value was measured according to ASTM 1512-21 standard. The ash content was measured according to ASTM D 1506:2015 standard. The carbon, hydrogen, nitrogen, and sulfur contents were measured according to DIN 51732:2014-07 standard. The zinc content was measured by inductively coupled plasma optical emission spectrometry (ICP OES). Pressure-assisted microwave digestion was carried out beforehand, for example using microwave and nitric acid. The measurement was carried out according to ASTM D8371-20 standard. Internal rubber testing of recycled acetylene black

[0070] In the following study, the internal rubber properties of rAB (recycled acetylene black, filler composition) according to the present invention were compared with the internal rubber properties of brand-new acetylene black, carbon black recovered from waste tires, and brand-new standard furnace black.

[0071] The rubber compound was prepared by a two-step mixing process. Using a HAAKE TM Rheomix kneader with a cavity volume of 0.379 liters and equipped with a tangential mixing rotor. The rotor speed was 50 rpm and the cavity temperature was 65 °C. Chloroprene rubber and butyl rubber were mixed for 1 minute, then 70 wt% of the filler and ZnO were added. After 90 seconds, the ram was lifted and swept, then the remaining 30 wt% of the filler and processing oil were added and mixing continued for 90 seconds. After lifting the ram and sweeping again, mixing continued for 90 seconds. After that, the compound was poured onto a two-roll mill to cool and sheet. Ensure that the mixing temperature does not exceed 160 °C. The compound was left standing overnight, then phenolic resin was added in an open two-roll mill. Ensure that the mixing temperature does not exceed 110 °C. The vulcanizate was vulcanized at 190 °C for 30 minutes. Example 2 Rubber properties

[0072] Six different rubbers were prepared and vulcanized. The composition of the rubbers is listed in Table 5: Table 5 Rubber compositions. The raw material concentrations are reported in phr.

[0073] Component information: · Butyl 301 (IIR rubber) and Baypren 110 (chloroprene rubber), purchased from Arlanxeo Deutschland GmbH; · N660 and N330, purchased from Orion Engineered Carbons GmbH; · rCB ReOil RB 615, purchased from Reoil Sp.z o.o.; · Y200 BDS acetylene black (pure) AB, purchased from Orion Engineered Carbons GmbH; · SP-1045 octylphenol novolac resin-based curing resin, purchased from Safi-Alcan; · Process oil P 100, purchased from Schilland Seillacher; · ZnO, purchased from Arnsperger Chemicals GmbH.

[0074] The hardness was measured according to DIN 53505:2000 - 08.

[0075] The tensile strength, elongation at break, 100% modulus, 200% modulus, 300% modulus and 500% modulus were measured according to DIN 53504:2017 - 03.

[0076] After curing of the rubber composition, the change of torque with curing time was measured using a moving die rheometer (MDR 2000E) according to ISO 6502 - 3:2018.

[0077] The tear resistance was measured according to DINISO 34 - 1:2016 - 09, Method B, using a notched angular specimen as variant (b), measuring the force required to widen a pre - formed notch.

[0078] The thermal conductivity was determined according to ASTM E 1461 - 2011.

[0079] TOPO is a measure of the filler dispersion determined by surface topography (including Medalia correction), and is carried out according to the procedures described in "Filler Dispersion Analysis by Topography Measurements" by A. Wehmeier, Technical Report TR 820, Degussa GmbH, as well as "Entwicklung eines Verfahrens zur Charakterisierung der Füllstoffdispersion in Gummimischungen mittels einer Oberflächentopographie" by A. Wehmeier, Thesis, 1998 at the Münster University of Applied Sciences and DE 199 17975C2.

[0080] Two carbon black grades N660 and N330 are the applicant's conventional furnace black, and the main difference lies in their specific surface area and structure. The product rCB (recycled carbon black) is a filler composition obtained by pyrolyzing passenger car and truck tires and is used for comparison as in the other two examples. The filler composition rAB (recycled acetylene black) is a product according to the present invention and is obtained by pyrolyzing vulcanized bladder compounds.

[0081] The product rAB contains 5.9% by weight of zinc. Taking this into account, in C4 containing brand-new acetylene black, the contents of Y200 BDS and zinc oxide are adjusted accordingly. This means that compared with C3, the ZnO concentration in the rubber compound C4 increases and the acetylene black concentration decreases, but the zinc and acetylene concentrations are similar to those in C6. The properties of the six rubbers are listed in Table 6.

[0082] The comparison between C1 (N660) and C2 (N330) shows that the thermal conductivity of the rubber compound is independent of the specific surface area. N660 has a specific STSA of 34 m 2 / g, while the STSA of N330 is more than twice that of N660, being 76 m 2 / g. However, rubber compounds with equal contents of N330 and N660 have very similar thermal conductivities (Table 6). Compared with C6 using the filler composition rAB of the present invention, C1 and C2 also exhibit lower thermal conductivities.

[0083] Compared with C3 (AB), the rubber compound C4 (with adjusted AB and ZnO) deliberately reduces the content of acetylene black and increases the content of Zn substance. The preparation of C4 aims to study the effects of lower acetylene black content and higher Zn concentration in butyl rubber. However, if added separately, reducing the acetylene black content and increasing the ZnO concentration will not result in a shorter curing time.

[0084] Surprisingly, the rubber compound C6 with a Zn component mixed in the acetylene black filler composition has the lowest curing time tc80 and thus the fastest curing kinetics. This is reflected in an extremely short tc80 time of only 14.54 minutes and a difference between tc80 and tc5 of only 13.76 minutes.

[0085] When comparing the rubber compound C5 containing fillers from the recycling process and recycled carbon black rCB with the rubber compound C6 containing rAB, we can conclude that the rubber compound containing the filler composition rAB according to the present invention performs excellently in all aspects, including dispersibility (extremely low TOPO value), curing kinetics (short tc80), mechanical properties (higher modulus at 300% elongation, higher tensile strength, higher elongation at break, and higher tear resistance), and thermal conductivity. The rubber-internal properties of the rubber compounds in Table 6 are shown in Table 5.

Claims

1. A filler composition comprising or consisting of the following components: (a) Acetylene black, (b) Zinc and / or zinc compounds, and optionally (c) Ash.

2. The composition according to claim 1, consisting of the following components: (a) About 75 to about 99.5% by weight of acetylene black, (b) About 0.2 to about 10% by weight of said zinc and / or zinc compounds, and optionally (c) About 0.5 to about 15% by weight of ash, provided that the sum of the above contents is 100% by weight.

3. The composition according to claim 1 or 2, wherein said zinc and / or zinc compounds are selected from metallic zinc, zinc oxide, complexes and coordination compounds of zinc, aggregates of zinc with coke particles, and mixtures thereof.

4. The composition according to claims 1 to 3, having - from about 25 to about 200 m 2 / g BET surface area; and / or - an OAN of about 80 to about 400 ml / 100 g and / or - a particle size of less than 15 μm.

5. A filler composition obtainable or obtained by the following steps: (a) Providing a vulcanized capsule stock; (b) Pyrolyzing said capsule stock to obtain a product mixture consisting of a solid residue, oil and gas fractions; (c) Removing the oil and gas phase from the solid residue; and (d) Grinding and / or granulating the solid residue.

6. A method for manufacturing a filler composition, comprising the following steps or consisting of the following steps: (a) Providing a vulcanized capsule stock; (b) Pyrolyzing said capsule stock to obtain a product mixture consisting of a solid residue, oil and gas fractions; (c) Removing the oil and gas phase from the solid residue; and (d) Grinding and / or granulating the solid residue of step (c).

7. The method according to claim 6, wherein said pyrolysis is carried out at a temperature of about 300 to about 1000 °C.

8. The method according to claim 6 or 7, wherein the pyrolysis is carried out for about 30 to about 350 minutes.

9. A stock, comprising or consisting of the following components: (a) At least one synthetic and / or natural vulcanizable rubber or polymer; and (b) The filler composition according to any one of claims 1 to 5.

10. The stock according to claim 9, exhibiting - at 150 °C, a thermal conductivity of about 0.15 to about 0.5 W / (m*K), and / or - a TOPO defect area of less than 2%.

11. A method for shortening the vulcanization time in the production process of rubber, tires and / or vulcanized capsule stocks, comprising the following steps or consisting of the following steps: (a) Providing a vulcanizable rubber or vulcanizable rubber blend or polymer; (b) Adding the filler composition according to any one of claims 1 to 5; (c) Vulcanizing the mixture of step (b); and optionally (d) Molding the vulcanized product to obtain a tire or a vulcanized capsule.

12. Use of the filler composition according to claim 1 or 6 as an additive in the production of organic resins, polymers, vulcanizable rubbers and / or elastomers, particularly in the production of tire and / or vulcanized capsule stocks.

13. Use of the filler composition according to claims 1 to 5 as an additive in battery production.

14. Use of the filler composition according to claims 1 to 5 as an additive in the production of adhesives and sealants.

15. Use of the filler composition according to claims 1 to 5 as an additive in the production of conductive compounds, wires and cables.

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