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PROCESS FOR THE PREPARATION OF STYRENE-BUTADIENE RUBBERS COMPRISING RECYCLED RUBBER POWDER

20250270392 ยท 2025-08-28

    Inventors

    Cpc classification

    International classification

    Abstract

    A process for preparing a styrene-butadiene rubber includes micronized recycled rubber powder and includes the following steps: preparing a suspension having micronized recycled rubber powder, water and at least one surfactant; mixing the suspension from step (a) with at least one styrene-butadiene latex to obtain a styrene-butadiene latex having micronized recycled rubber powder; and subjecting the latex from step (b) to coagulation to obtain a coagulated styrene-butadiene rubber having micronized recycled rubber powder. In step (a), the particle size of the micronized recycled rubber powder ranges from 0.05 mm to 0.8 mm; the at least one surfactant is present in an amount ranging from 0.5% by weight to 3% by weight, with respect to total weight of the micronized recycled rubber powder; and the micronized recycled rubber powder has a concentration in water ranging from 1% by weight to 50% by weight, with respect to the total weight of the water.

    Claims

    1. A process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder, said process comprising the following steps: (a) preparing a suspension comprising micronized recycled rubber powder, water and at least one surfactant; (b) mixing the suspension obtained in step (a) with at least one styrene-butadiene latex to obtain a styrene-butadiene latex comprising micronized recycled rubber powder; and (c) subjecting the latex obtained in step (b) to coagulation to obtain a coagulated styrene-butadiene rubber comprising micronized recycled rubber powder; wherein: in step (a) the particle size of said micronized recycled rubber powder is ranging from 0.05 mm to 0.8 mm; in step (a) said at least one surfactant is present in an amount ranging from 0.5% by weight to 3% by weight, with respect to the total weight of said recycled rubber powder; and in step (a) said micronized recycled rubber powder has a concentration in water ranging from 1% by weight to 50% by weight, with respect to the total weight of said water.

    2. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein in step (a) said at least a surfactant is selected from the group consisting of: non-ionic surfactants such as polyoxyethylene derivatives of fatty acids, alkyl-polyglucosides, ethanolamides, ethoxylated amides, ethoxylated amines, ethoxylated acids, polyoxyethylene alkyl-ethers, or mixtures thereof; and/or anionic surfactants such as: salts formed by carbon atom long chains terminated with a carboxylate or sulfonate group [such as sodium lauryl sulfate (SLS), sodium lauryl ethoxy sulfate (SLES)], alkyl-benzene-sulphonic acids (ABS), polysulfonated aromatic ethers, or mixtures thereof; sodium, potassium, lithium, or ammonium salts, of fatty acids, saturated or unsaturated, containing from 6 to 22 carbon atoms in the molecule such as caproic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, or mixtures thereof, or mixtures of said salts; sodium, potassium, lithium, or ammonium salts, of modified resin acids which are obtained by dimerization, disproportionation, hydrogenation, modification of resin acid mixtures containing abietic acid, neoabietic acid, palustric acid, levopimaric acid, or mixtures thereof, or mixtures of said salts; and/or cationic surfactants such as long-chain quaternary ammonium salts [such as benzalkonium chloride (BAC), cetyl-trimethylammonium bromide (CTAB), hexadecyltrimethylammonium bromide], or mixtures thereof, and/or amphoteric surfactants such as coco-amidopropyl-betaine, dodecyl-betaine, lecithin, aminocarboxylic acids, or mixtures thereof.

    3. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said step (a) is carried out at a temperature ranging from 20 C. to 90 C. for a variable time depending on the size of the mixer and sufficient to obtain a homogeneous suspension, for a time ranging from 5 minutes to 60 minutes.

    4. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein in said step (b) said at least one styrene-butadiene latex has an amount of styrene-butadiene polymer ranging from 10% by weight to 50% by weight, with respect to the total weight of said latex and an amount of linked styrene ranging from 10% by weight to 60% by weight, with respect to the total weight of said latex.

    5. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein in said step (b) the suspension obtained in step (a) is added in such an amount to have an amount of micronized recycled rubber powder ranging from 5% by weight to 95% by weight, with respect to the total weight of the styrene-butadiene rubber contained in the latex.

    6. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said step (b) is carried out at a temperature ranging from 20 C. to 90 C., for a variable time depending on the size of the mixer and sufficient to obtain a styrene-butadiene latex comprising micronized recycled rubber powder, wherein said powder is homogeneously distributed in the latex, for a period of time ranging from 1 minute to 45 minutes.

    7. A process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder includes the following steps: (a1) preparing a suspension comprising micronized recycled rubber powder, water and at least one surfactant; and (c1) mixing the suspension obtained in step (a) with at least one styrene-butadiene latex and subjecting the whole to coagulation to obtain a coagulated styrene-butadiene rubber comprising micronized recycled rubber powder; wherein: in step (a1) the particle size of said micronized recycled rubber powder is ranging from 0.05 mm to 0.8 mm; in step (a1) said at least one surfactant is present in an amount ranging from 0.5% by weight to 3% by weight, with respect to total weight of said micronized recycled rubber powder; and in step (a1) said micronized recycled rubber powder has a concentration in water ranging from 1% by weight to 50% by weight, with respect to the total weight of said water.

    8. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder, the process includes the following steps: (a1) preparing a suspension comprising micronized recycled rubber powder, water and at least one surfactant; and (c1) mixing the suspension obtained in step (a) with at least one styrene-butadiene latex and subjecting the whole to coagulation to obtain a coagulated styrene-butadiene rubber comprising micronized recycled rubber powder; wherein: in step (a1) the particle size of said micronized recycled rubber powder is ranging from 0.05 mm to 0.8 mm; in step (a1) said at least one surfactant is present in an amount ranging from 0.5% by weight to 3% by weight, with respect to total weight of said micronized recycled rubber powder; in step (a1) said micronized recycled rubber powder has a concentration in water ranging from 1% by weight to 50% by weight, with respect to the total weight of said water, wherein said step (a1) is carried out according to claim 2.

    9. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said step (c) and step (c1) are carried out in the presence of at least one coagulation agent selected from alkylamine-epichloridine copolymers.

    10. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said step (c) and step (c1) are carried out at a temperature ranging from 40 C. to 90 C., for a variable time depending on the size of the coagulation mixer, the amount of suspension obtained in step (a) or step (a1) and of the used styrene-butadiene latex, the temperature and the pH, the used stirring system, for a time ranging from 5 minutes to 120 minutes.

    11. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said step (c) and step (c1) are carried out at a pH lower than or equal to 5.

    12. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein at least one inorganic acid such as sulfuric acid, phosphoric acid is added in said step (c) and step (c1), said at least one organic acid being added in such an amount to maintain the pH lower than or equal to 5, for the entire duration of said step (c) and step (c1).

    13. The process for the preparation of a styrene-butadiene rubber comprising micronized recycled rubber powder according to claim 1, wherein said process is carried out in batch or continuously.

    14. A vulcanizable elastomeric composition comprising at least one styrene-butadiene rubber comprising micronized recycled rubber powder obtained according to claim 1, at least one filler selected from the group consisting of carbon black, silica, or mixtures thereof, and at least one vulcanizing agent.

    15. The vulcanized product obtained from the vulcanization of the elastomeric composition according to claim 14.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0092] The present disclosure will now be illustrated in greater detail through an embodiment with reference to FIGS. 1 and 2 reported below.

    [0093] FIG. 1 schematically illustrates a first embodiment of the process of the present disclosure. For this purpose, the micronized recycled rubber powder (micronized powder), water and at least one surfactant (for example, Potassium Soap 80% Gresinox 578 M) are fed to a first mixer (1) equipped with a stirring system (e.g. a 45 Pitch Blade type impeller or a 3-blade propeller A310 from Lightnin), obtaining a suspension (turbid) [step (a)]. The suspension (turbid) obtained in step (a) is fed to a second mixer (2) (called pre-mixer) equipped with a stirring system (for example, a 45 Pitch Blade type impeller, or a 3-blade propeller A310 from Lightnin), wherein the styrene-butadiene latex (SBR latex) and any other components [for example, surfactants, extender oils, antioxidants (other components)] are also fed, obtaining a styrene-butadiene latex comprising micronized recycled rubber powder [(step (b)](SBR latex+micronized powder). The obtained latex is fed to a third mixer (i.e., a coagulation mixer called coagulation tank) (3) equipped with a stirring system (for example, a 45 Pitch Blade type impeller or a 3-blade propeller A310 from Lightnin) to which an acid (for example, sulfuric acid) and a coagulation agent (for example, Floquat FL 2250) are also fed, and subjected to coagulation [step (c)], pH neutralisation (for example, with an aqueous solution of sodium carbonate), washing with water and removal of water (dewatering) obtaining a styrene-butadiene rubber comprising micronized recycled rubber powder (eSBR rubber+micronized powder).

    [0094] FIG. 2 schematically illustrates a second embodiment of the process of the present disclosure. For this purpose, the micronized recycled rubber powder (micronized powder), water and at least one surfactant (for example, Potassium Soap 80% Gresinox 578 M) are fed to a first mixer (1) equipped with a stirring system (for example, a 45 Pitch Blade type impeller or a 3-blade propeller A310 from Lightnin), obtaining a suspension (turbid) [step (a1)]. To a second mixer (2) (called pre-mixer) equipped with a stirring system (for example, a 45 Pitch Blade type impeller, or a 3-blade propeller A310 from Lightnin), the styrene-butadiene latex (SBR latex) and any other components [(for example, surfactants, extender oils, antioxidants (further components)] are fed, obtaining a styrene-butadiene latex comprising said other components (SBR+further components). The obtained latex is fed to a third mixer (i.e. a third mixer (i.e., a coagulation mixer known as a coagulation tank) (3) equipped with a stirring system (for example, a 45 Pitch Blade type impeller or a 3-blade propeller A310 from Lightnin) to which the suspension (turbid) obtained in step (a1), an acid (for example, sulfuric acid) and a coagulation agent (for example, Floquat FL 2250) are also fed, and the whole is subjected to coagulation [step (c1)], pH neutralisation (for example, with an aqueous solution of sodium carbonate), washing with water and removal of water (dewatering) obtaining a styrene-butadiene rubber comprising micronized recycled rubber powder (eSBR rubber+micronized powder).

    DETAILED DESCRIPTION OF THE DISCLOSURE

    [0095] In order to better understand the present disclosure and to put it into practice, some illustrative and non-limiting examples thereof are reported below.

    Example 1

    [0096] In a first 20-litre mixer, equipped with a stirring system consisting of a 45 Pitch Blade type impeller, 67.5 g of micronized recycled rubber powder deriving from end-of-life tyres (ELT) [rubber powder B.0/0.35 (d.sub.90<0.35 mm)-Albatros], 675 ml of water and 13.5 g of a 10% by weight aqueous solution of anionic surfactant (Potassium Soap 80% Gresinox 578 M-Parchem) are loaded: the whole was kept, under stirring, at 310 rpm, for 5 minutes, at 60 C., obtaining 765 g of a suspension (turbid).

    [0097] The suspension (turbid) was sent to a second 20-litre mixer (called pre-mixer) equipped with a stirring system consisting of a 45 Pitch Blade type impeller, wherein 3.2 litres of styrene-butadiene latex (styrene-butadiene polymer amount equal to 21% by weight and styrene amount equal to 40% by weight, with respect to the total weight of said latex), 2.7 g of antioxidant (Irganox 1520L-Basf), 252 g of aromatic oil [RAE (Residual Aromatic Extract)-Clematis RL-Eni) and 25 g of a 10% by weight aqueous solution of anionic surfactant (Potassium Soap 80% Gresinox 578 M-Parchem) were loaded: the whole was kept, under stirring, at 310 rpm, for 10 minutes, at 60 C., obtaining 4.25 litres of styrene-butadiene latex comprising micronized recycled rubber powder.

    [0098] In a third 70-litre mixer (i.e. coagulation mixer called coagulation tank) equipped with a stirring system consisting of a 45 Pitch Blade type impeller, 10 litres of deionised water were loaded and, after bringing the temperature to 70 C., sulfuric acid (Aldrich) was gradually fed until a pH value equal to 3 was reached: subsequently, 4.25 litres of styrene-butadiene latex comprising micronized recycled rubber powder obtained as reported above at a flow rate equal to about 0.7 litres/minute and 13.4 grams of coagulation agent (Floquat FL 2250-SNF) were loaded. At the end, the whole was kept, under stirring, at 100 rpm, for a further 30 minutes, at a temperature of 70 C. and at pH equal to 3: during coagulation it is necessary to add again sulfuric acid (Aldrich) in order to maintain the pH equal to 3. Subsequently, still under stirring, at 100 rpm, after having brought the temperature to 80 C., sodium carbonate (Aldrich) was added in order to bring the pH to a value equal to 6.5-7: once the desired pH was reached, the coagulated latex was filtered in order to recover the styrene-butadiene rubber crumbs comprising micronized recycled rubber powder, which were then washed under a flow of deionised water, at a temperature of about 70 C., for 10 minutes.

    [0099] After 10 minutes, the styrene-butadiene rubber crumbs comprising micronized recycled rubber powder were dried in an air oven at 100 C., for 24 hours (residual moisture: lower than 1%).

    Example 2

    [0100] Example 2 was carried out operating under the same operating conditions as Example 1 using different amounts of components: Table 1 shows the amounts of the various components for the production of styrene-butadiene rubber comprising micronized recycled rubber powder.

    TABLE-US-00001 TABLE 1 COMPONENTS AMOUNT SUSPENSION PREPARATION (TURBID) (FIRST MIXER) Water 1.35 litres Potassium Soap 80% Gresinox 578 M 27 grams (aqueous solution at 10% by weight) ELT rubber powder B.0/0.35 135 grams (d.sub.90 < 0.35 mm) SECOND MIXER (PRE-MIXER) Styrene-butadiene latex 3.2 litres RAE (Residual Aromatic Extract) - 252 grams Clematis RL Irganox 1520 L 2.7 grams Potassium Soap 80% Gresinox 578 M 25 grams (aqueous solution at 10% by weight) Suspension (Turbid) 1512 grams THIRD MIXER (COAGULATION TANK) Water 10 litres Latex from pre-mixer 4.99 litres Floquat FL 2250 13.4 g Sulfuric acid q.s.* Sodium carbonate q.s.* *as much as is sufficient.

    Example 3

    [0101] Example 3 was carried out operating under the same operating conditions as Example 1 using different amounts of components and a different aromatic oil [TDAE (Treated Distillated Aromatic Extract)-Norman 346-ORGKHIM]: Table 2 shows the amounts of the various components for the production of styrene-butadiene rubber comprising micronized recycled rubber powder.

    TABLE-US-00002 TABLE 2 COMPONENTS AMOUNT SUSPENSION PREPARATION(TURBID) (FIRST MIXER) Water 1.35 litres Potassium Soap 80% Gresinox 578 M 27 grams (aqueous solution at 10% by weight) ELT rubber powder B.0/0.35 (d.sub.90 < 0.35 135 grams mm) SECOND MIXER (PRE-MIXER) SBR latex 3.2 litres TDAE (Treated Distillated Aromatic 252 grams Extract) - Norman 346 Irganox 1520 L 2.7 grams Potassium Soap 80% Gresinox 578 M 25 grams (aqueous solution at 10% by weight) Suspension (Turbid) 1512 grams THIRD MIXER (COAGULATION TANK) Water 10 litres Latex from pre-mixer 4.99 litres Floquat FL 2250 13.4 g Sulfuric acid q.s.* Sodium carbonate q.s.* *as much as is sufficient.

    Example 4

    [0102] Example 4 was carried out operating under the same operating conditions as in Example 1 using different amounts of components, a different styrene-butadiene latex (styrene-butadiene polymer amount equal to 21% by weight and styrene amount equal to 23.5% by weight, with respect to the total weight of said latex) and without aromatic oil: Table 3 shows the amounts of the various components for the production of styrene-butadiene rubber comprising micronized recycled rubber powder.

    TABLE-US-00003 TABLE 3 COMPONENTS AMOUNT SUSPENSION PREPARATION (TURBID) (FIRST MIXER) Water 1.35 litres Potassium Soap 80% Gresinox 578 M 27 grams (aqueous solution at 10% by weight) ELT rubber powder B.0/0.35 135 grams (d.sub.90 < 0.35 mm) SECOND MIXER (PRE-MIXER) SBR latex 3.2 litres Irganox 1520 L 2.7 grams Potassium Soap 80% Gresinox 578 M 25 grams (aqueous solution at 10% by weight) Suspension (Turbid) 1512 grams THIRD MIXER (COAGULATION TANK) Water 10 litres Latex from pre-mixer 4.99 litres Floquat FL 2250 13.4 g Sulfuric acid q.s.* Sodium carbonate q.s.* *as much as is sufficient.

    Example 5

    [0103] The styrene-butadiene rubbers comprising micronized recycled rubber powder obtained in Examples 1 and 2 reported above were used to produce compounds for treads.

    [0104] The compound comprising the styrene-butadiene rubber comprising micronized recycled rubber powder obtained in Example 1 is hereinafter referred to as (A).

    [0105] The compound comprising the styrene-butadiene rubber comprising micronized recycled rubber powder obtained in Example 2 is hereinafter referred to as (B).

    [0106] The physical and mechanical properties of the above compounds were compared with those of two other compounds, defined as follows: [0107] (C) compound comprising styrene-butadiene rubber (Europrene 1739-Versalis) and micronized recycled rubber powder deriving from end-of-life tyres (ELT) [rubber powder B.0/0.35 (d.sub.90<0.35 mm)-Albatros] (10 phr) added by dry mixing; [0108] (D) compound comprising styrene-butadiene rubber (Europrene 1739-Versalis) and micronized recycled rubber powder deriving from end-of-life tyres (ELT) [rubber powder B.0/0.35 (d.sub.90<0.35 mm)-Albatros] (20 phr) added by dry mixing.

    Preparation of Compounds

    [0109] The compounds were prepared in a 1.6 litre Banbury type internal mixer: the operating conditions are reported in Table 4, the components and the amounts are given in Table 5.

    TABLE-US-00004 TABLE 4 Operating conditions Banbury Time 60 rpm; FF*: 0.70; T: 60 C. (min) Compounds (A) and (B) Compounds (C) and (D) Banbury feeding 0 Styrene-butadiene rubber + Europrene 1739 ELT (obtained from Example 1 and Example 2) 1 carbon black + oil + carbon black + ELT + other components reported oil + other components in Table 5 (excluding reported in Table 5 sulfur, TBBS and TBDT 80) (excluding sulfur, TBBS and TBDT 80) 3 carbon black carbon black 6 discharge discharge (T.sub.max 140 C.) (T.sub.max 140 C.) Acceleration 0 Discharged compound + Discharged compound + sulfur + TBBS and TBDT 80 sulfur + TBBS and TBDT 80 2 discharge discharge (T.sub.max 105 C.) (T.sub.max 105 C.) *FF: Filling Factor.

    [0110] The samples were then vulcanized at 160 C. according to ISO 6502-1: 2018 Standard.

    TABLE-US-00005 TABLE 5 Com- Com- Com- Com- pound A pound B pound C pound D COMPONENTS (phr) (phr) (phr) (phr) e-SBR + 147.5 157.5 micronized powder Europrene 1739 137.5 137.5 ELT 10 20 N 220 80 80 80 80 Aromatic oil 10 10 10 10 WB 220 2 2 2 2 6-PPD 0.8 0.8 0.8 0.8 Stearic acid 2.0 2.0 2.0 2.0 TMQ 0.6 0.6 0.6 0.6 ZnO 80 3.8 3.8 3.8 3.8 TBBS 2.0 2.0 2.0 2.0 TBTD 80 0.4 0.4 0.4 0.4 Sulfur 2.3 2.3 2.3 2.3 [0111] e-SBR+micronized powder: styrene-butadiene rubber comprising micronized recycled rubber powder obtained as reported above in Examples 1 and 2; [0112] Europrene 1739 (e-SBR): oil-extended styrene-butadiene rubber obtained in emulsion (TDAE-oil) (Versalis); [0113] ELT: rubber powder B.0/0.35 (d.sub.90<0.35 mm)-Albatros; [0114] N220: carbon black; [0115] aromatic oil: TDAE (Treated Distillated Aromatic Extract)-NORMAN 346-ORGKHIM; [0116] WB 220 (processing aid): Struktol; [0117] Stearic acid: Sigma Aldrich; [0118] TMQ (antioxidant): 2,2,4-trimethyl-1,2-dihydroquinoline, polymerised (Nord Chemie); [0119] Rhenogran ZnO 80 (activator): zinc oxide (Lanxess); [0120] TBBS (accelerator): N-tert-butyl-2-benzothiazilsulfenamide, Vulkacit NZ/EGC (Lanxess); [0121] TBTD 80 (accelerator): tetrabutylthiurame disulfide (Sigma Aldrich).

    [0122] Table 6 shows the physical-mechanical properties of the vulcanized compounds obtained and the corresponding methods of measurement.

    TABLE-US-00006 TABLE 6 Properties Unit of Standard Compounds Definition measurement Method (A) (B) (C) (D) Mooney (MU) ASTM D1646 62.2 74.5 62.8 65.9 viscosity (2018) Stress (MPa) ASTM D412C 16.8 16.5 16.4 15.9 at Break (2016) Elongation (%) ASTM D412C 501 479 475 467 at Break (2016) Hardness (shore A) ASTM D2240 60 60 59 60 (2015) Tear (N/mm) DELFT ISO34 33.4 35.2 32.5 33.3 resistance (2015) Abraded (mm.sup.3/40 m) ASTM D5963 125 123 136 139 volume (2019)
    From the data reported in Table 6, it is clear that the compounds comprising styrene-butadiene rubber comprising micronized recycled rubber powder obtained in accordance with the process of the present disclosure [Compound (A) and Compound (B)] maintain or even improve the physical-mechanical properties compared to the compounds comprising styrene-butadiene rubber and recycled rubber powder obtained by dry mixing [Compound (C) and Compound (D)]. In particular, it should be noted that Compound (A) and Compound (B) show an improvement in relation to tear resistance and abraded volume compared to Compound (C) and Compound (D), respectively.

    Example 6

    [0123] The physical-mechanical properties of compound (B) were compared with those of compound (E), comprising styrene-butadiene rubber comprising micronized recycled rubber powder SBR+20 phr ELT with a particle size ranging from 0.8 mm to 2.5 mm (Tritogran 1-P-0.8-2.5 mm-Tritogom), said rubber being obtained by operating as described in Example 1.

    [0124] The compound (E) was obtained by operating under the operating conditions reported in Example 5 (i.e. same mixing, acceleration and vulcanization cycle) and the same components and amounts reported in Table 5 for compound (B) (i.e. 157.5 phr of e-SBR+micronized recycled rubber powder+same phr of said further components).

    [0125] Table 7 shows the properties of the vulcanized compounds obtained and the relative measuring methods.

    TABLE-US-00007 TABLE 7 Properties Unit of Compounds Definition measurement Method (B) (E) Mooney viscosity (MU) ASTM D1646 74.5 65.4 (2018) Stress at Break (MPa) ASTM D412C 16.5 12.3 (2016) Elongation at Break (%) ASTM D412C 479 434 (2016) Hardness (shore A) ASTM D2240 60 58 (2015) Tear resistance (N/mm) DELFT ISO34 35.2 34.9 (2015) Abraded volume (mm.sup.3/40 m) ASTM D5963 123 128 (2019)
    From the data reported in Table 7, it is clear that the compound comprising styrene-butadiene rubber comprising micronized recycled rubber powder obtained in accordance with the process of the present disclosure [Compound (B)] has improved physical-mechanical properties compared to the compound comprising styrene-butadiene rubber and recycled rubber powder having a larger particle size [Compound (E)].