Rubber mixtures containing at least one processing aid of formula (i)

Abstract

The invention relates to rubber mixtures containing at least one rubber, at least one hydroxyl-group-containing oxidic filler, at least one strengthening additive from the group of sulfurous organic silanes, at least one cross-linker from the group of sulfur and sulfur donors, and at least one processing aid of formula (I), to the production and use thereof, and to the vulcanized materials obtained therefrom by way of the vulcanization process, in particular in the form of tires, parts of tires or technical rubber products.

Description

[0001] Rubber mixtures containing at least one processing aid of the formula (I)

[0002] The invention relates to rubber mixtures containing at least one rubber, at least one hydroxyl-containing oxidic filler, at least one reinforcing additive from the series of sulfur-containing organic silanes, at least one crosslinker from the series of sulfur and sulfur donors and at least one processing aid of the formula (I), their preparation and use, and the vulcanizates obtainable thereby by the vulcanization process, in particular in the form of tires, parts of tires or technical rubber articles.

[0003] A major challenge in the development of tire rubber compounds is improving the trade-off between rolling resistance, wet braking, and abrasion. To optimize application-relevant properties of vulcanizates, such as tires derived from rubber compounds, such as the aforementioned trade-off, ever-increasing amounts of silica and reinforcing additives are being added to the rubber compounds. However, this results in a significant increase in the viscosity of the vulcanizates, necessitating the use of efficient processing aids.

[0004] In WO2010136345A1, functionalized rubbers were used together with a trimethylolpropane (TMP) fatty acid mixture in rubber compounds to improve rolling resistance and wet skid resistance. However, TMP has since been classified as reprotoxic Category 2. Therefore, there is a great need to find less toxicologically harmful substitutes for TMP that exhibit comparable performance to that of the trimethylolpropane fatty acid mixture in WO200136345A1 in rubber compounds.

[0005] The present invention is therefore based on the object of providing rubber mixtures that are less toxicologically harmful compared to rubber mixtures of WO2010136345A1, in which the application-relevant properties, preferably wet braking, rolling resistance, and abrasion resistance, more preferably Mooney viscosity, are equally good, preferably better, than those of the corresponding TMP-containing rubber mixtures or vulcanizates. Even more preferably, other application-related properties such as breaking strength and elongation at break are equally good, preferably better, than those of the corresponding TMP-containing rubber mixtures or vulcanizates.

[0006] Surprisingly, it has now been found that when at least one processing aid of the formula (I) is used in rubber mixtures containing at least one rubber, at least one hydroxyl-containing oxidic filler, at least one reinforcing additive from the series of sulfur-containing organic silanes, and at least one crosslinker from the series of sulfur and sulfur donors, rubber mixtures can be obtained which achieve this objective compared to the TMP-containing equivalents. The present invention accordingly relates to rubber mixtures containing

[0007] - at least one rubber,

[0008] - at least one hydroxyl-containing oxidic filler,

[0009] - at least one reinforcing additive from the series of sulphur-containing organic silanes, and

[0010] - at least one crosslinker from the series sulfur and sulfur donor, further comprising at least one processing aid of the formula (I):

[0011] R 1 R 2 NZNR 3 R 4 Formula (I) where R 1 , R 2 , R 3 and R 4 each independently selected from

[0012] (CH2)XCH(OH)(CH2)WH Formula (A) and

[0013] (CH2) y CH3Formula (B) with x = 0-8, y = 0-8, w= 0-6, where Z is a linear or branched, substituted or unsubstituted Ci-C 22 Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, and wherein at least two of the radicals R 1 , R 2 , R 3 and R 4are independently selected from formula (A), and wherein the at least one processing aid of the formula (I) is preferably present in the rubber mixture in an amount of 0.1 - 30 phr, particularly preferably 0.5 - 25 phr, very particularly preferably 1 - 20 phr, most preferably 3 - 15 phr.

[0014] The loss factor tan delta at 60 °C, preferably at a measurement frequency of 10 Hz, is used as an indicator for rolling resistance. The tan delta at 0 °C or 23 °C, preferably at a measurement frequency of 10 Hz, is used as an indicator for wet braking, and the DIN abrasion is considered an indicator for abrasion resistance.

[0015] rubber

[0016] The rubber mixtures according to the invention contain at least one rubber.

[0017] This can be, for example, natural rubber (NR) and / or synthetic rubber.

[0018] Preferred polar and non-polar synthetic rubbers are

[0019] ACM - Polyacrylate Rubber

[0020] AEM - Ethylene acrylate rubber

[0021] BR - Polybutadien

[0022] ABR - Butadiene / acrylic acid C1-C4-alkyl ester copolymer

[0023] CR - Polychloroprene IR - Polyisoprene

[0024] SBR - styrene / butadiene copolymers with styrene contents of 1 - 60, preferably 20-50 wt.%

[0025] IIR - Isobutylene / isoprene copolymers

[0026] NBR - butadiene / acrylonitrile copolymers with acrylonitrile contents of 5-60, preferably 10-50 wt.%

[0027] HNBR - partially hydrogenated or fully hydrogenated NBR rubber

[0028] EPM - ethylene / propylene copolymers

[0029] EPDM - ethylene / propylene / diene copolymers

[0030] EVM - ethylene / vinyl acetate copolymers

[0031] SIBR - Styrene-Isoprene-Butadiene Rubber

[0032] ENR - Epoxidized natural rubber

[0033] SNBR - Acrylonitrile-styrene / butadiene rubber

[0034] HNBR - Hydrogenated acrylonitrile / butadiene rubber

[0035] XNBR - Carboxylated acrylonitrile / butadiene rubber

[0036] HXNBR - Hydrogenated carboxylated acrylonitrile / butadiene rubber

[0037] Particularly preferred polar and non-polar synthetic rubbers are BR, SBR, SIBR, IR and ENR.

[0038] The at least one synthetic rubber may be unfunctionalized or functionalized.

[0039] The rubber mixtures according to the invention can contain at least one functionalized synthetic rubber. The above statements for the unfunctionalized synthetic rubbers apply, with the difference that in the case of functionalized synthetic rubbers, these are functionalized.

[0040] In the context of the present invention, functionalized synthetic rubber is understood to mean a synthetic rubber which is substituted on the main chain and / or on the end groups by one or more functional groups, preferably selected from carboxyl groups, mercaptan groups, alkoxysilane groups, siloxane groups, hydroxyl groups, ethoxy groups, epoxy groups, amino groups, phthalocyanine groups, silane sulfide groups and metal atom-containing groups, particularly preferably selected from mercaptan groups, alkoxysilane groups and hydroxyl groups, very particularly preferably selected from mercaptan groups and alkoxysilane groups.

[0041] Unfunctionalized synthetic rubbers within the scope of the present invention do not contain the aforementioned substitutions by functional groups.

[0042] The rubber mixtures according to the invention preferably contain at least one functionalized synthetic rubber, particularly preferably selected from the group consisting of polar and non-polar functionalized synthetic rubbers. The at least one functionalized synthetic rubber is preferably selected from the group consisting of functionalized SBR, functionalized BR, and functionalized IR rubber, particularly preferably from functionalized SBR and functionalized BR rubber.

[0043] The rubber mixtures according to the invention preferably contain at least one functionalized SBR rubber and / or one functionalized BR rubber, particularly preferably at least one functionalized SBR and at least one functionalized BR rubber.

[0044] In a preferred embodiment, the at least one rubber is selected from the group consisting of natural rubber and synthetic rubbers, preferably at least one functionalized synthetic rubber, particularly preferably at least one functionalized synthetic rubber selected from the group consisting of functionalized SBR, functionalized BR and functionalized IR rubber, very particularly preferably from functionalized SBR and functionalized BR rubber.

[0045] Preferably, the at least one functionalized SBR rubber is substituted on the main chain and / or at the end groups by one or more functional groups, in particular selected from mercaptan groups, alkoxysilane groups, and hydroxyl groups, particularly preferably by several functional groups that are mercaptan groups and alkoxysilane groups. Preferably, the at least one functionalized SBR rubber is SPRINTAN® SLR 3402 from Trinseo.

[0046] The functionalized SBR rubber can be solution-polymerized styrene-butadiene rubber (SSBR) or emulsion-polymerized styrene-butadiene rubber (ESBR), whereby a mixture of at least one functionalized SSBR and at least one functionalized ESBR can also be used.

[0047] The molecular weight (Mw) of the styrene-butadiene copolymers can vary over a wide range. Styrene-butadiene copolymers with an Mw of 250,000 to 600,000 g / mol are preferred, and those with an Mw of 350,000 to 500,000 g / mol are particularly preferred.

[0048] Preferably, the at least one functionalized BR rubber is substituted on the main chain and / or at the end groups by one or more functional groups selected from mercaptan groups, alkoxysilane groups, and hydroxyl groups, particularly preferably by alkoxysilane groups. Preferably, the at least one functionalized BR rubber is NIPOL® BR 1261 from Zeon.

[0049] The molecular weight of the butadiene polymers can vary over a wide range. Butadiene polymers with a Mw of 250,000 to 5,000,000 g / mol are preferred. Polybutadiene with a cis content greater than or equal to 90 wt. % is referred to as high-cis type, and polybutadiene with a cis content less than 90 wt. % is referred to as low-cis type. A low-cis polybutadiene is, for example, Li-BR (lithium-catalyzed butadiene rubber) with a cis content of 20 to 50 wt. %. Within the scope of the present invention, a high-cis type of functionalized BR rubber is preferred.

[0050] The rubber mixtures according to the invention preferably contain 0 to 100 phr of at least one functionalized synthetic rubber, particularly preferably 50 to 100 phr, very particularly preferably 70-100 phr.

[0051] The rubber mixtures according to the invention preferably contain at least one functionalized SBR and at least one functionalized BR rubber in a weight ratio SBR:BR of 100:0 to 0:100, particularly preferably of 90:10 to 10:90, very particularly preferably of 90:10 to 30:70, very particularly preferably of 80:20 to 50:50.

[0052] The rubber mixtures according to the invention preferably contain 0 to 100 phr of at least one unfunctionalized synthetic rubber and / or at least one natural rubber, particularly preferably 0 to 50 phr, very particularly preferably 0 to 30 phr.

[0053] Fillers

[0054] The at least one hydroxyl-containing oxidic filler is preferably selected from the group consisting of silicic acids, synthetic silicates and natural silicates.

[0055] The content of hydroxyl-containing oxidic fillers in the rubber mixtures according to the invention is preferably 0.1 to 250 phr, particularly preferably 20 to 200 phr, very particularly preferably 25 to 180 phr and most preferably 30 to 160 phr.

[0056] Oxidic fillers containing hydroxyl groups are preferably those from the series of

[0057] - Silicas, in particular with a specific surface area (BET) of 5 to 1000, preferably 20 to 400 m 2 / g, preferably with primary particle sizes of 100 to 400 nm, the silicas optionally also being present as mixed oxides with other metal oxides, such as Al, Mg, Ca, Ba, Zr, Ti oxides,

[0058] - synthetic silicates, such as aluminum silicate, alkaline earth silicates such as magnesium silicate or calcium silicate, with specific surface areas (BET) of 20 to 400 m 2 / g, preferably with primary particle sizes of 10 to 400 nm and

[0059] - natural silicates, such as kaolin and other naturally occurring silicas, as well as mixtures thereof.

[0060] The above-mentioned BET surface areas are determined according to DIN ISO 9277. The primary particle size specifications are based on measurements using a particle analysis device using scattered light. The particle size calculation is based on the Mie theory, which describes the interaction between light and matter (DIN / ISO 13320).

[0061] The silicas are preferably obtainable by precipitation of solutions of silicates or flame hydrolysis of silicon halides.

[0062] The rubber mixtures according to the invention preferably contain at least one hydroxyl-containing oxidic filler from the series of silicas, in particular with a specific surface area (BET) in the range from 5 to 1000, preferably 20 to 400 m 2 / g in an amount of 0.1 to 250 phr, preferably 20 to 200 phr, particularly preferably 25 to 180 phr, most preferably 30 to 160 phr.

[0063] The rubber mixtures according to the invention may contain at least one carbon black as filler.

[0064] In a preferred embodiment, the rubber mixtures according to the invention contain at least one carbon black as filler.

[0065] The rubber mixtures according to the invention preferably contain at least one carbon black in an amount of 0.1 to 120 phr, particularly preferably 0.1 to 100 phr, very particularly preferably 1 to 70 phr, most preferably 2 to 40 phr.

[0066] Preferred carbon blacks are those obtainable by the lamp black, furnace black or gas black process and which have a specific surface area (BET) in the range of 20 to 200 m 2 / g, such as SAF, ISAF, IISAF, HAF, FEF, or GPF carbon blacks. The rubber mixtures according to the invention preferably contain at least one carbon black with a specific surface area (BET) in the range of 20 to 200 m 2 / g .

[0067] The rubber mixtures according to the invention particularly preferably contain as fillers at least one of the above-mentioned silicas and at least one of the above-mentioned carbon blacks.

[0068] The rubber mixtures according to the invention very particularly preferably contain as fillers 25 to 180 phr, preferably 30 to 160 phr, of at least one of the abovementioned silicas and 1.0 to 70 phr, preferably 2.0 to 40 phr, of at least one of the abovementioned carbon blacks.

[0069] The total amount of carbon black and silica-based fillers in the rubber mixture according to the invention is preferably 26 to 250 phr, particularly preferably 32 to 200 phr.

[0070] Crosslinkers and vulcanization accelerators

[0071] The rubber mixtures according to the invention contain at least one crosslinker selected from the group consisting of sulfur and sulfur donors. They may also contain at least one vulcanization accelerator.

[0072] The rubber mixtures according to the invention contain at least one crosslinker from the series sulfur and sulfur donors.

[0073] Sulfur can be used in elemental, soluble, or insoluble form. The rubber mixtures according to the invention particularly preferably contain at least one sulfur donor and / or sulfur, most preferably sulfur.

[0074] Examples of sulfur donors include dimorpholyl disulfide (DTDM), 2-morpholinodithiobenzothiazole (MBSS), caprolactam disulfide, dipentamethylene thiuram tetrasulfide (DPTT), tetramethylthiuram disulfide (TMTD) and tetrabenzyl thiuram disulfide (TBzTD).

[0075] The rubber mixtures according to the invention generally contain 0.1 to 20 phr, preferably 0.5 to 10 phr, particularly preferably from 1.0 to 8 phr and most preferably 1 to 4 phr of at least one crosslinker from the group consisting of sulfur and sulfur donors.

[0076] Zinc oxide may be present in the rubber mixtures according to the invention.

[0077] Preferred rubber mixtures according to the invention contain zinc oxide with a BET surface area of ​​2 to 100 m 2 / g, preferably 2 to 70 m 2 / g. BET surface areas of zinc oxide can be measured according to DIN ISO 9277.

[0078] In general, zinc oxide is present in the rubber mixtures according to the invention in an amount of 0 to 20 phr, preferably 0.1 to 10 phr, particularly preferably 1 to 5 phr.

[0079] Vulcanization accelerator

[0080] The rubber mixtures according to the invention may contain at least one vulcanization accelerator.

[0081] The rubber mixtures according to the invention preferably contain at least one vulcanization accelerator.

[0082] The amount of at least one vulcanization accelerator in the mixture according to the invention is 0 to 20 phr, preferably 0.1 to 10 phr and particularly preferably 0.2 to 5 phr.

[0083] The at least one vulcanization accelerator is particularly preferably selected from the group of mercapto-benzothiazoles, thiocarbamates, dithiocarbamates, thiurams, thiazoles, sulfenamides, thiazole-sulfenamides, xanthates, bi- or polycyclic amines, thiophosphates, dithiophosphates, caprolactams, thiourea derivatives, guanidines, cyclic disulfanes and amines, in particular zinc diamine diisocyanate, hexamethylenetetramine, 1,3-bis(citraconimidomethyl)benzene, and very particularly preferably from the group of sulfenamides, very particularly preferably N-cyclohexylbenzothiazole-sulfenamide (CAS No.: 95-33-0).

[0084] The rubber mixtures according to the invention preferably contain at least one vulcanization accelerator which contains N-cyclohexylbenzothiazole sulfenamide.

[0085] In the mixture according to the invention, guanidine-containing compounds may be contained as the at least one vulcanization accelerator or may not be contained at all.

[0086] Guanidine-containing compounds are, for example, diphenylguanidine (DPG), di-ortho-tolyl-guanidine (DOTG), 1-(ortho-tolyl)biguanide, substituted diphenylguanidines and other organic guanidine derivatives in which the guanidine function is substituted with one or more Ci-Cs alkyl groups, Cz-Cs alkenyl groups, Ce-Cs aryl groups, C7-C10 aralkyl groups and / or Ci-Cs heteroalkyl groups.

[0087] For the purposes of the present invention, the term "substituted diphenylguanidines" preferably refers to diphenylguanidines in which at least one phenyl ring is substituted, preferably both phenyl rings are substituted. A wide variety of substituents are possible.Preferably, a substituent of a phenyl ring is selected from the group consisting of C1-C20-alkyl, which is substituted or unsubstituted, C2-C20-alkenyl, which is substituted or unsubstituted and contains one or more double bonds, C2-C20-alkynyl, which is substituted or unsubstituted and contains one or more triple bonds, C5-C20-aryl, which is substituted or unsubstituted, heteroaryl, which is substituted or unsubstituted, is five to twenty-membered and contains one or more heteroatoms, C5-Cu-cycloalkyl, which is substituted or unsubstituted, heterocycloalkyl, which is substituted or unsubstituted, is three to eight-membered and contains one or more heteroatoms, and heteroatoms.

[0088] In a preferred embodiment, the mixture according to the invention contains at least one guanidine-containing compound in the at least one vulcanization accelerator, particularly preferably DPG.

[0089] Most preferably, the at least one vulcanization accelerator in the rubber mixture according to the invention contains N-cyclohexylbenzothiazole sulfenamide and DPG; most preferably, the at least one vulcanization accelerator consists of N-cyclohexylbenzothiazole sulfenamide and DPG.

[0090] The total amount of crosslinker and vulcanization accelerator in the rubber mixtures is preferably 0.5 to 30 phr, particularly preferably 1.1 to 18 phr, most preferably 1.2 to 9 phr. Processing aids

[0091] The rubber mixtures according to the invention contain at least one processing aid of the formula (I):

[0092] R 1 R 2 NZNR 3 R 4 Formula (I) where R 1 , R 2 , R 3 and R 4 each independently selected from

[0093] (CH2)XCH(OH)(CH2)WH Formula (A) and

[0094] (CH2) yCH3Formula (B) with x = 0-8, y = 0-8, w= 0-6, where Z is a linear or branched, substituted or unsubstituted Ci-C 22 Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, and wherein at least two of the radicals R 1 , R 2 , R 3 and R 4 are independently selected from formula (A), and wherein the at least one processing aid of the formula (I) is preferably present in the rubber mixture in an amount of 0.1 - 30 phr, particularly preferably 0.5 - 25 phr, very particularly preferably 1 - 20 phr, most preferably 3 - 15 phr.

[0095] In formula (I) x = 0-8, preferably x = 0-3, particularly preferably x = 0-2, most preferably x = 1, and y = 0-8, preferably y = 0-3, particularly preferably y = 0-2, most preferably y = 0, and w = 0-6, preferably w = 0-3, particularly preferably w = 0-1, most preferably w = 1.

[0096] In formula (I), Z is a linear or branched, substituted or unsubstituted Ci-C 22 Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, particularly preferably linear or branched, substituted or unsubstituted C2-Ce alkylene chain, very particularly preferably linear or branched, substituted or unsubstituted C3 alkylene chain.

[0097] In a preferred embodiment, Z is a linear, substituted or unsubstituted Ci-C 22Alkylene chain, preferably linear, substituted or unsubstituted C1-C10 alkylene chain, particularly preferably linear, substituted or unsubstituted C2-C8 alkylene chain, very particularly preferably linear, substituted or unsubstituted C3 alkylene chain.

[0098] In a particularly preferred embodiment, Z = (CH2) Z with z = 1-22, preferably z = 1-10, particularly preferably z = 2-6, very particularly preferably z = 3. Preference is given to rubber mixtures according to the invention comprising the at least one processing aid of the formula (I) with Z = (CHa)z with z = 1-10, x = 0-3, y = 0-3, w = 0-3, particularly preferably with z = 2-6, x = 0-2, y = 0-2, w = 0-1, most preferably with z = 3, x = 1, y = 0, w = 1.

[0099] In an alternative embodiment, Z is a branched, substituted, or unsubstituted C1-C22 alkylene chain, preferably a branched, substituted, or unsubstituted C1-C10 alkylene chain, wherein the branches can also form a cyclic ring, preferably C1-C10 cycloalkylene. In this alternative embodiment, Z is preferably selected from 2,2,4-trimethylhexamethylene, 2,4,4-trimethylhexamethylene, and a compound of formula (C):

[0100] Formula (C) comprises four stereoisomers, all of which are encompassed by the compound of formula (C). When Z is selected from the compound of formula (C), a selection of one or more stereoisomers from formula (C) is possible.

[0101] Preferred are R 1 and R 2 in which at least one processing aid of the formula (I) is independently selected from formula (A). R are particularly preferably 1 and R 2equal and selected from formula (A).

[0102] Preferred are R 3 and R 4 in which at least one processing aid of the formula (I) is independently selected from formula (B). R are particularly preferably 3 and R 4 equal and selected from formula (B).

[0103] In a particularly preferred embodiment, Z = (CHa)z with z = 2-6, most preferably z =3, and R 1 and R 2 are the same and selected from formula (A) with x = 0-2, most preferably x=1 , and with w = 0-1 , most preferably w = 1 , and R 3 and R 4 are equal and selected from formula (B) with y = 0- 2, most preferably y = 0.

[0104] In a most preferred embodiment, the at least one processing aid of the formula (I) is / V, / V-dimethyl- / V', / V -bis(2-hydroxypropyl)-1,3-diamine. In a further preferred embodiment, at least three of the radicals R 1 , R 2 , R3 and R 4 independently selected from formula (A). These at least three radicals are particularly preferably identical, with x = 0-2, most preferably x = 1, and with w = 0-1, most preferably w = 1.

[0105] In addition to the at least one processing aid of the formula (I), rubber mixtures according to the invention may also contain one or more further processing aids which are different from the at least one processing aid of the formula (I).

[0106] Preferably, the at least one processing aid of the formula (I) represents at least 20% by weight, particularly preferably at least 40% by weight, very particularly preferably at least 70% by weight, most preferably at least 80% by weight of the processing aids which may be present in the rubber mixture according to the invention, wherein the % by weight is based on the total amount of the processing aids.

[0107] These further processing aids can be, for example, alcohols, amides, acids, esters, surfactants, and / or amides. A preferred further processing aid in the rubber mixture according to the invention is selected from the group consisting of alcohols, acids, and esters, preferably from the group consisting of acids, particularly preferably selected from palmitic acid and stearic acid, most preferably stearic acid.

[0108] In the context of this invention, processing aids preferably serve to improve the processability of the rubber mixture, particularly preferably to improve the transport of the rubber mixture through the mixer.

[0109] Preferably, the processing aids in the context of the present invention are different from the other ingredients of the rubber mixture according to the invention, such as the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the series of sulfur-containing organic silanes, the at least one crosslinker from the series of sulfur and sulfur donors, the optional at least one vulcanization accelerator and the optional one or more rubber aids.

[0110] The at least one processing aid of the formula (I) is preferably present in the rubber mixtures according to the invention in an amount of 0.1 - 30 phr, particularly preferably 0.5 - 25 phr, very particularly preferably 1 - 20 phr, most preferably 3 - 15 phr.

[0111] The rubber mixtures according to the invention contain at least one reinforcing additive from the series of sulfur-containing organic silanes. Preferred sulfur-containing organic silanes are bifunctional sulfur-containing organic silanes that have at least one alkoxy, cycloalkoxy, or phenoxy group on the silicon atom and, as another functionality, a group selected from -SCN, -SH, or -Sx-, where x = 2 to 8.

[0112] Particularly preferred are sulfur-containing silanes containing alkoxysilyl groups and very particularly preferred are sulfur-containing organic silanes containing trialkoxysilyl groups.

[0113] Most preferably, the rubber mixtures according to the invention contain one or more sulfur-containing silanes from the series bis-(triethoxysilylpropyl)-tetrasulfane, bis-(triethoxysilylpropyl)-disulfane and 3-(triethoxysilyl)-1-propanethiol.

[0114] Liquid sulfur-containing silanes can be coated on a carrier (dry liquid) for improved metering and / or dispersibility. The content of sulfur-containing silanes in these "dry liquids" is preferably between 30 and 70 parts by weight, particularly preferably between 40 and 60 parts by weight, per 100 parts by weight of dry liquid.

[0115] The rubber mixtures according to the invention generally contain 0.1 to 20 phr, preferably 0.5 to 15 phr and particularly preferably 1.0 to 10 phr of at least one reinforcing additive from the series of sulfur-containing organic silanes.

[0116] Rubber additives

[0117] The rubber mixtures according to the invention may further contain one or more rubber auxiliaries. Examples of suitable rubber auxiliaries include anti-aging agents, coupling agents, heat stabilizers, light stabilizers, flame retardants, processing aids, impact modifiers, plasticizers, tackifiers, blowing agents, dyes, pigments, waxes, extenders, organic acids, retarders, and anti-reversion agents.

[0118] The rubber mixtures according to the invention may contain one or more anti-aging agents. Suitable anti-aging agents are amine-based agents such as diaryl-p-phenylenediamines (DTPD), octylated diphenylamine (ODPA), phenyl-α-naphthylamine (PAN), and phenyl-β-naphthylamine (PBN), preferably those based on phenylenediamine, e.g. B. N,N'-dicyclohexyl-p-phenylenediamine (CCPD), N-isopropyl-N'-phenyl-p-phenylenediamine, N 1 ,3-dimethylbutyl-N'-phenyl-p-phenylenediamine (6PPD), N-1 ,4-dimethylpentyl-N'-phenyl-p phenylenediamine (7PPD), N,N'-bis-(1 ,4-dimethylpentyl)-p-phenylenediamine (77PD) and phosphites such as tris-(nonylphenyl)phosphite, polymerized 2,2,4-trimethyl-1 ,2-dihydroquinoline (TMQ), methyl-2-mercapto-benzimidazole (MMBI) and zinc methylmercaptobenzimidazole (ZMMBI) and mixtures thereof.Particularly preferably, the at least one anti-aging agent is selected from the group consisting of N,N'-dicyclohexyl-p-phenylenediamine (CCPD) and N,1,3-dimethyl-ibutyl-N'-phenyl-p-phenylenediamine (6PPD). Processing aids are intended to act between the rubber particles and counteract frictional forces during mixing, plasticizing, and molding. As processing aids, the rubber mixtures according to the invention can contain all lubricants customary for processing plastics, for example hydrocarbons, such as oils, e.g.aromatic process oil, paraffins and PE waxes, fatty alcohols with 6 to 20 C atoms, ketones, carboxylic acids such as fatty acids and montanic acids, oxidized PE wax, aromatically modified cycloaliphatic hydrocarbon resins, metal salts of carboxylic acids, carboxylic acid amides and carboxylic acid esters, for example with the alcohols ethanol, fatty alcohols, glycerol, ethanediol, pentaerythritol and long-chain carboxylic acids as acid component.

[0119] To reduce flammability and smoke development during combustion, the rubber mixtures according to the invention can contain flame retardants. Examples of flame retardants used include antimony trioxide, phosphoric acid esters, chlorinated paraffin, aluminum hydroxide, boron compounds, zinc compounds (except ZnO), molybdenum trioxide, ferrocene, calcium carbonate, or magnesium carbonate.

[0120] Before crosslinking, other plastics can also be added to the rubber mixtures according to the invention, which act, for example, as polymeric processing aids or impact strength improvers. These plastics are preferably selected from the group consisting of homo- and copolymers based on ethylene, propylene, butadiene, styrene, methylstyrene, coumarene, indene, vinyl acetate, vinyl chloride, glycidyl acrylate, glycidyl methacrylate, acrylates and methacrylates with alcohol components of branched or unbranched C1 to C10 alcohols, with polyacrylates with identical or different alcohol radicals from the group of C4 to C8 alcohols, in particular butanol, hexanol, octanol and 2-ethylhexanol, polymethyl methacrylate, methyl methacrylate-butyl acrylate copolymers, methyl methacrylate-butyl methacrylate copolymers, ethylene-vinyl acetate copolymers, chlorinated polyethylene, ethylene-propylene copolymers, ethylene-propylene-diene copolymers being particularly preferred.

[0121] Known adhesives based on resorcinol, formaldehyde, and silica, the so-called RFS direct adhesion systems, are used. These direct adhesion systems can be used in any amount of the rubber mixture according to the invention at any time during mixing into the rubber mixtures according to the invention.

[0122] In addition, the rubber mixtures according to the invention may contain at least one vulcanization retarder.

[0123] Examples of suitable vulcanization retarders include sulfenamide retarders based on acidic compounds such as phthalic acid, phthalic anhydride, benzoic acid, or salicylic acid, and α-nitroso compounds based on diphenylamine or trimethyldihydroquinoline. Preferably, the at least one vulcanization retarder is selected from the group consisting of sulfenamide retarders, most preferably selected from N-cyclohexylthiophthalimide and N-phenyl-N-(trichloromethylsulfenyl)benzenesulfonamide, most preferably N-cyclohexylthiophthalimide.

[0124] Typical amounts for at least one vulcanization retarder are 0.01 - 10 phr.

[0125] The rubber auxiliaries contained in the mixture according to the invention are preferably different from the other ingredients of the rubber mixture according to the invention, such as the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the series of sulfur-containing organic silanes, the at least one crosslinker from the series of sulfur and sulfur donors, the optional at least one vulcanization accelerator, the at least one processing aid of the formula (I) and the optional further processing aids.

[0126] The rubber auxiliaries can be added to the rubber mixtures according to the invention in the amounts customary for these auxiliaries, which also depend on the intended use of the vulcanizates produced therefrom. Typical amounts are, for example, 0.1 to 30 phr.

[0127] However, if a rubber auxiliary overlaps with one of the other ingredients of the rubber mixtures according to the invention, for example the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the series of sulfur-containing organic silanes, the at least one crosslinker from the series of sulfur and sulfur donors, the optional at least one vulcanization accelerator, the at least one processing auxiliary of the formula (I) and / or and the optional further processing auxiliary agents, this rubber auxiliary is preferably only contained in the rubber mixture according to the invention as a supplement to the general and preferred quantities specified for this other ingredient.

[0128] Particularly preferred rubber mixtures according to the invention are those containing

[0129] - 50 to 100 phr of at least one functionalized synthetic rubber, preferably 70 - 100 phr, preferably of a functionalized BR rubber and / or functionalized SBR rubber,

[0130] - 0 to 50 phr of at least one natural rubber and / or unfunctionalized synthetic rubber, preferably 0 to 30 phr,

[0131] - 20 to 200 phr of at least one hydroxyl-containing oxidic filler,

[0132] - 0.5 to 15 phr of at least one reinforcing additive from the group of sulfur-containing organic silanes, preferably bifunctional sulfur-containing organic silanes which have at least one alkoxy, cycloalkoxy, or phenoxy group on the silicon atom and as other functionality a group selected from -SCN, -SH or -Sx- with x = 2 to 8, particularly preferably alkoxysilyl group-containing sulfur-containing silanes and very particularly preferably trialkoxysilyl group-containing sulfur-containing organic silanes,

[0133] - 0.1 to 120 phr of at least one carbon black, preferably 0.1 to 100 phr,

[0134] - 0.5 to 10 phr of at least one crosslinker from the series sulphur donor and sulphur,

[0135] - 0.1 to 10 phr zinc oxide,

[0136] - 0.1 to 10 phr of at least one vulcanization accelerator,

[0137] - 0.1 to 30 phr of at least one processing aid of the formula (I), preferably 0.5 - 25 phr, particularly preferably 1 - 20 phr, very particularly preferably 3 - 15 phr.

[0138] The above-mentioned further preferred ranges of the individual components also apply to these preferred mixtures.

[0139] Process for producing rubber mixtures

[0140] A further subject of the present invention is a process for producing the rubber mixtures according to the invention, characterized in that the respective components are mixed in a mixing process.

[0141] Preferably, at least one rubber is mixed together in the presence of at least one hydroxyl-containing oxidic filler, at least one reinforcing additive from the group of sulfur-containing organic silanes, optionally at least one vulcanization accelerator, and at least one processing aid of the formula (I) and optionally further rubber auxiliaries and optionally further processing aids in the stated general and preferred amounts at a temperature in the range from 50 to 180°C, particularly preferably 60 to 170°C.

[0142] The rubber mixtures according to the invention are produced in the usual way in known mixing units, such as rollers, internal mixers, downstream mixing roll mills and mixing extruders at shear rates of 1 to 1000 see -1 .

[0143] The rubber mixtures according to the invention are preferably produced in a three-stage mixing process.

[0144] Preferably, in a first mixing stage, rubber, the fillers and optionally further rubber auxiliaries mentioned above, preferably anti-aging agents, and optionally the at least one vulcanization accelerator, preferably the guanidine-containing vulcanization accelerator, and the at least one processing aid of the formula (I) and optionally further processing aids are incorporated into the rubber in an internal mixer (kneader).

[0145] Preferably, the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the group of sulfur-containing organic silanes, optionally the at least one vulcanization accelerator, preferably the guanidine-containing vulcanization accelerator, and the at least one processing aid of the formula (I) and optionally further rubber aids are mixed in the first mixing stage in the process for producing the rubber mixtures according to the invention.

[0146] Mixing temperatures in the internal mixer can reach values ​​of up to 180°C. The temperature in the first mixing stage is preferably 130 to 180°C, particularly preferably 140 to 170°C.

[0147] The second step is preferably the so-called post-tweezing, preferably at 130-180°C, particularly preferably at 160°C. Post-tweezing can be carried out, for example, in an internal mixer.

[0148] Preferably, in a third mixing stage, at least one crosslinker from the group consisting of sulfur and sulfur donor, as well as optionally at least one further vulcanization accelerator and optionally further rubber auxiliaries, are added to the rubber mixture obtained from the second mixing stage. The temperature in the third mixing stage is preferably 50-130°C, particularly preferably 60-120°C.

[0149] The processing aid of formula (I) can be added at any time during mixing, preferably in the first mixing stage at a temperature in the range from 130°C to 180°C, preferably at a temperature of 140 to 170°C.

[0150] In a particularly preferred embodiment of the process for producing the rubber mixtures according to the invention, firstly the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the group of sulfur-containing organic silanes, optionally the at least one vulcanization accelerator, preferably the guanidine-containing vulcanization accelerator, and the at least one processing aid of the formula (I) and optionally further rubber aids and optionally further processing aids are mixed, preferably at 130 to 180°C, and then the at least one crosslinker from the series sulfur and sulfur donor and optionally the at least one further vulcanization accelerator and optionally further rubber aids are added to the resulting rubber mixture, preferably at 50 - 130°C.

[0151] Process for producing rubber vulcanizates

[0152] The present invention further relates to a process for producing rubber vulcanizates, characterized in that the rubber mixture according to the invention is heated at temperatures of 120 to 200°C, preferably at 140 to 180°C. The process for producing the rubber vulcanizates according to the invention can be carried out over a wide pressure range, preferably at a pressure in the range of 10 to 200 bar.

[0153] The present invention further relates to rubber vulcanizates which are obtainable by vulcanization of the rubber mixtures according to the invention.

[0154] molded body

[0155] The rubber vulcanizates according to the invention are suitable for the production of all types of molded articles, such as tire components, technical rubber articles such as damping elements, roller coverings, conveyor belt coverings, belts, spinning cops, seals, golf ball cores, shoe soles. They are particularly suitable for the production of tires and tire parts, such as tire treads, subtreads, carcasses, tire sidewalls, reinforced sidewalls for runflat tires, and apex compounds. Tire treads also include treads for summer, winter, and all-season tires, as well as treads for passenger car, truck, and light truck tires.

[0156] Preferred molded articles are tires and tire parts containing a rubber vulcanizate according to the invention.

[0157] use

[0158] The present invention further relates to the use of at least one processing aid of the formula (I)

[0159] R 1 R2 NZNR 3 R 4 Formula (I) where R 1 , R 2 , R 3 and R 4 each independently selected from

[0160] (CH2)XCH(OH)(CH2)WH Formula (A) and

[0161] (CH2) y CH3Formula (B) with x = 0-8, y = 0-8, w= 0-6, where Z is a linear or branched, substituted or unsubstituted Ci-C 22 Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, and wherein at least two of the radicals R 1 , R 2 , R 3 and R 4 are independently selected from formula (A), in an amount of 0.1 to 30 phr, preferably 0.5 - 25 phr, particularly preferably 1 - 20 phr, most preferably 3 - 15 phr, preferably with Z = (CHa)z with z = 2-6, particularly preferably z = 3, and R 1 and R 2are the same and selected from formula (A) with x = 0-2, preferably x=1 , and with w = 0-1 , preferably w = 1 , and R 3 and R 4 are identical and selected from formula (B) with y = 0-2, preferably y = 0, in sulfur-crosslinkable rubber compounds, the vulcanizates obtainable therefrom and the moldings obtainable therefrom, for treating, preferably improving, the conflicting objectives of rolling resistance, wet braking and abrasion.

[0162] Most preferred is the use of the at least one processing aid of the formula (I), which is / V, / V-dimethyl- / V', / V -bis(2-hydroxypropyl)-1,3-diamine, in an amount of 0.1 to 30 phr, preferably 0.5 - 25 phr, particularly preferably 1 - 20 phr, very particularly preferably 3 - 15 phr, in sulfur-crosslinkable rubber mixtures, the vulcanizates obtainable therefrom and the moldings obtainable therefrom, for treating, preferably for improving, the conflicting objectives of rolling resistance, wet braking and abrasion.

[0163] The descriptions and preferred ranges given for the components contained and optionally contained in the rubber mixture according to the invention apply analogously to, among other things, the disclosed processes and uses as well as the vulcanizates and moldings.

[0164] The descriptions and preferred areas given also apply to, among others, the rubber mixtures, vulcanizates, moldings, processes and uses according to the invention, regardless of whether they were disclosed for the aforementioned in the plural (e.g. rubber mixtures) or in the singular (e.g. rubber mixture).

[0165] The invention will be explained with reference to the following examples, but is not limited thereto.

[0166] Implementation examples

[0167] Table 1 : List of ingredients, abbreviations and manufacturers

[0168] Processing aid A: Mixture of 70 wt.% stearic acid, 25 wt.% TMP, 5 wt.% polyethylene glycol, based on the total weight of the processing aid A. Production of the rubber vulcanizates

[0169] The rubber mixtures of the non-inventive reference mixtures (Examples 1 and 2) and the inventive rubber mixture (Example 3) were prepared according to the recipes given in Table 2. Example 2 was prepared based on WO2010136345A1. All rubber mixtures of the examples contain stearic acid, whereas the rubber mixture of Example 1 contains no further processing aid, the rubber mixture of Example 2 contains a larger amount of stearic acid compared to Examples 1 and 3, as well as TMP, and the inventive rubber mixture of Example 3 further contains the processing aid of the formula (I), here A / ,A / -dimethyl-A / ',A / -bis(2-hydroxypropyl)-1,3-diamine.

[0170] The rubber compounds were produced in the following steps:

[0171] 1. Mixing stage:

[0172] ■ NIPOL® BR1261 and SPRINTAN® SLR 3402 are placed in an internal mixer and mixed for approximately 30 seconds.

[0173] ■ Add half of ULTRASIL® 7000GR and mix Sl® 75 for about 60 seconds.

[0174] ■ Add half of ULTRASIL® 7000GR, CORAX®N 234, as well as stearic acid, Vulkanox® 4020, Vulkanox® HS, Antilux® 654, Vivatec 500, Escorez 5600 or RHENOGRAN® DPG-80, processing aid A / ,A / -dimethyl-A / ',A / -bis(2-hydroxypropyl)-1,3-diamine, mix for approximately 60 seconds, then sweep. Mix until a temperature of 160 °C is reached, then mix for 4 minutes at 160 °C.

[0175] After the first mixing stage, the mixed material is taken up by a downstream rolling mill and formed into a sheet, strip, or pellet. It is then stored at room temperature for 24 hours. Processing temperatures are 70°C.

[0176] 2nd mixing stage:

[0177] Afterwards, mixing took place in an internal mixer until a temperature of 160°C was reached (the so-called post-tweezing).

[0178] After completion of the second mixing stage, the mixed piece is taken up by a downstream rolling mill and formed into a plate, strip or pellets and stored for 24 hours at room temperature.

[0179] 3. Mixing stage:

[0180] The addition of sulfur, zinc oxide and the vulcanization accelerator Rhenogran® CBS-80 took place in the internal mixer for 2 minutes at 100 °C.

[0181] After completion of the third mixing stage, the mixed piece is formed into a sheet, strip, or pellet using a rolling mill and stored at room temperature for 24 hours. Processing temperatures are 70°C. The inventive rubber mixture of Example 3 shows no specks on the surface, indicating good mixing of the additives used.

[0182] Table 2: Components of the rubber mixtures according to the invention Quantities in phr (parts by weight per 100 parts of rubber)

[0183] Technical inspection

[0184] The vulcanizates produced at 160°C from the rubber compounds of Examples 1-3 were subjected to the technical tests specified below. The results are shown in Table 3.

[0185] The following test procedures were used for the tests on test specimens:

[0186] Mooney viscosity measurement The determination was carried out using a shear disk viscometer in accordance with ASTM D 1646. Viscosity can be determined directly from the force that rubbers and rubber compounds exert during processing. In the Mooney shear disk viscometer, a corrugated disk is enclosed at the top and bottom with sample substance and rotated in a heatable chamber at approximately two revolutions per minute. The force required for this is measured as torque and corresponds to the respective viscosity. The sample is usually preheated to 100°C for one minute; the measurement lasts a further 4 minutes, during which the temperature is kept constant. The viscosity is specified together with the respective test conditions, for example ML (1 + 4) 100°C (Mooney viscosity, rotor size L, preheating time and test time in minutes, test temperature).

[0187] Rheometer (vulcameter) used and vulcanization / curing time

[0188] The vulcanization process on the MDR (moving die rheometer) and its analytical data were measured on a Monsanto rheometer MDR 2000 according to ASTM D5289-95.

[0189] The curing time (t95) is determined as the time required for 95% of the rubber to cure. The temperature chosen was 160°C.

[0190] Determination of elongation at break, breaking strength, modulus 300

[0191] These measurements were carried out according to DIN 53504 (tensile test, bar S2, 5-fold measurement).

[0192] Determination of Shore A hardness

[0193] Measurement of Shore hardness (Shore A) according to DIN 53505 at 23 °C (triple measurement).

[0194] Rebound resilience

[0195] Measurement of rebound resilience at 23 °C and 60 °C (triple measurement) according to DIN 53512.

[0196] Determination of DIN abrasion

[0197] The simplest method for determining abrasive wear is the so-called DIN abrasion according to DIN ISO 4649. The test specimen made of the elastomer to be tested is subjected to a constant contact force and at a constant speed (40 min 1 ) is guided over a defined friction distance (40 m) over a test emery sheet mounted on a rotating cylinder. The material loss is then measured in mm 3 certainly.

[0198] Determination of the loss factor

[0199] The loss factor tan ö was determined at 0°C, 23 °C and 60°C and a measuring frequency of 10 Hz according to dynamic damping DIN 53513.

[0200] Determination of tear resistance

[0201] Tear resistance was determined according to DIN ISO 34-1:2015 (Graves, Determination of tear resistance - Part 1: Strip, angle, and arc-shaped test specimens). Table 3: Results of the technical tests

[0202] Conclusion

[0203] Example 2 (not according to the invention) shows that by adding the processing aid A, which contains TMP and larger amounts of stearic acid, the processing can be improved compared to the rubber mixture of Example 1 (not according to the invention), which contains less stearic acid.

[0204] By adding the processing aid of formula (I) to inventive example 3, the conflicting objectives of abrasion, rolling resistance, and wet braking could surprisingly be improved compared to example 2. The improvement in this conflicting objectives is evident in inventive example 3 by the increased tan delta values ​​at 0°C and 23°C and the lower value at 60°C compared to example 2, which contains the TMP-containing processing aid A. At the same time, the abrasion resistance of the inventive vulcanizate of example 3 increases, which can be seen from the reduced DIN abrasion value.

[0205] In the rubber mixture 3 according to the invention, the Mooney viscosity could be significantly reduced by adding the processing aid of the formula (I), A / ,A / -dimethyl-A / ', N -bis(2-hydroxypropyl)-1,3-diamine, compared to the reference mixture of Example 1. In addition, the vulcanization time (t95) was improved.

Claims

1 . Rubber mixture containing - at least one rubber, - at least one hydroxyl-containing oxidic filler, - at least one reinforcing additive from the series of sulphur-containing organic silanes, - at least one crosslinker from the series sulfur and sulfur donor, and further comprising at least one processing aid of the formula (I): R 1 R 2 NZNR 3 R 4 Formula (I) where R 1 , R 2 , R 3 and R 4 each independently selected from (CH 2 )XCH(OH)(CH 2 )WH Formula (A) and (CH 2 ) y CH 3 Formula (B) with x = 0-8, y = 0-8, w= 0-6, where Z is a linear or branched, substituted or unsubstituted Ci-C 22Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, and wherein at least two of the radicals R 1 , R 2 , R 3 and R 4 are independently selected from formula (A), and wherein the at least one processing aid of formula (I) is preferably present in the rubber mixture in an amount of 0.1 - 30 phr, particularly preferably 0.5 - 25 phr, very particularly preferably 1 - 20 phr, most preferably 3 - 15 phr.

2. Rubber mixture according to claim 1, characterized in that the at least one rubber is selected from the group consisting of natural rubber and synthetic rubbers, preferably at least one functionalized synthetic rubber, particularly preferably at least one functionalized synthetic rubber selected from the group consisting of functionalized SBR, functionalized BR and functionalized IR rubber, very particularly preferably from functionalized SBR and functionalized BR rubber.

3. Rubber mixture according to one of claims 1 or 2, characterized in that the at least one hydroxyl-containing oxidic filler is selected from the group consisting of silicas, synthetic silicates and natural silicates, and in an amount of 0.1 to 250 phr, preferably 20 to 200 phr, particularly preferably 25 up to 180 phr, most preferably 30 - 160 phr is contained in the rubber mixture.

4. Rubber mixture according to one of claims 1-3, characterized in that Z is a linear, substituted or unsubstituted C1-C22 alkylene chain, preferably linear, substituted or unsubstituted C1-C10 alkylene chain, particularly preferably linear, substituted or unsubstituted C2-C6 alkylene chain, very particularly preferably linear, substituted or unsubstituted C3 alkylene chain 5. Rubber mixture according to one of claims 1-4, characterized in that R 1 and R 2 are independently selected from formula (A), preferably that R 1 and R 2 are equal and are selected from formula (A).

6. Rubber mixture according to one of claims 1-5, characterized in that R 3 and R 4 are independently selected from formula (B), preferably that R 3 and R4 are equal and are selected from formula (B).

7. Rubber mixture according to one of claims 1-6, characterized in that Z = (CH2)Z with z = 2-6, preferably z = 3, and R 1 and R 2 are the same and are selected from formula (A) with x = 0-2, preferably x=1, and with w = 0-1, preferably w = 1, and R 3 and R 4 are equal and are selected from formula (B) with y = 0-2, preferably y = 0.

8. Rubber mixture according to one of claims 1-7, characterized in that the at least one processing aid of the formula (I) represents at least 20% by weight, preferably at least 40% by weight, particularly preferably at least 70% by weight, very particularly preferably at least 80% by weight of the processing aids which can be present in the rubber mixture according to the invention, wherein the % by weight is based on the total amount of the processing aids.

9. Rubber mixture according to one of claims 1-8, characterized in that it contains at least one vulcanization accelerator, preferably in an amount of 0.1 to 10 phr, particularly preferably 0.2 to 5 phr.

10. Rubber mixture according to one of claims 1-9, characterized in that the rubber mixture - 50 to 100 phr of at least one functionalized synthetic rubber, preferably 70 - 100 phr, preferably of a functionalized BR rubber and / or functionalized SBR rubber, - 0 to 50 phr of at least one natural rubber and / or unfunctionalized synthetic rubber, preferably 0 to 30 phr, - 20 to 200 phr of at least one hydroxyl-containing oxidic filler, - 0.5 to 15 phr of at least one reinforcing additive from the group of sulfur-containing organic silanes, preferably bifunctional sulfur-containing organic silanes, which have at least one alkoxy, cycloalkoxy or phenoxy group on the silicon atom and as other functionality a group selected from -SCN, -SH or -Sx- with x = 2 to 8, particularly preferably sulfur-containing silanes containing alkoxysilyl groups and very particularly preferably sulfur-containing organic silanes containing trialkoxysilyl groups, - 0.1 to 120 phr of at least one carbon black, preferably 0.1 to 100 phr, - 0.5 to 10 phr of at least one crosslinker from the series sulphur donor and sulphur, - 0.1 to 10 phr zinc oxide, - 0.1 to 10 phr of at least one vulcanization accelerator, preferably selected from the group of mercapto-benzothiazoles, thiocarbamates, dithiocarbamates, thiurams, thiazoles, sulfenamides, thiazolesulfenamides, xanthates, bi- or polycyclic amines, thiophosphates, dithiophosphates, caprolactams, thiourea derivatives, guanidines, cyclic disulfanes and amines, in particular zinc diamine diisocyanate, hexamethylenetetramine, 1,3-bis(citraconimidomethyl)benzene, and particularly preferably from the group of sulfenamides, very particularly preferably N-cyclohexylbenzothiazolesulfenamide (CAS No.: 95-33-0), and - 0.1 to 30 phr of at least one processing aid of the formula (I), preferably 0.5 - 25 phr, particularly preferably 1 - 20 phr, very particularly preferably 3 - 15 phr. 1 1. A process for producing the rubber mixtures according to the invention according to any one of claims 1-10, characterized in that the respective components are mixed in a mixing process.

12. Process according to claim 11, characterized in that in the process for producing the rubber mixture - firstly, the at least one rubber, the at least one hydroxyl-containing oxidic filler, the at least one reinforcing additive from the group of sulfur-containing organic silanes, optionally the at least one vulcanization accelerator, preferably the guanidine-containing vulcanization accelerator, and the at least one processing aid of the formula (I) and optionally further rubber auxiliaries and optionally further processing aids are mixed, preferably at 130 to 180°C, and - subsequently, at least one crosslinker from the series sulfur and sulfur donor and optionally at least one further vulcanization accelerator and optionally further rubber auxiliaries are added to the resulting rubber mixture, preferably at 50 - 130°C.

13. Vulcanizates obtainable by vulcanization of rubber mixtures according to one of claims 1 to 10.

14. Shaped articles, preferably technical rubber articles and tires, containing one or more rubber vulcanizates according to claim 13.

15. Use of at least one processing aid of the formula (I) R 1 R 2 NZNR 3 R 4 Formula (I) where R 1 , R 2 , R 3 and R 4 each independently selected from (CH 2 )XCH(OH)(CH 2 )WH Formula (A) and (CH 2 ) y CH 3Formula (B) with x = 0-8, y = 0-8, w= 0-6, where Z is a linear or branched, substituted or unsubstituted Ci-C 22 Alkylene chain, wherein the branches can also form a cyclic ring, preferably Ce-cycloalkylene, preferably linear or branched, substituted or unsubstituted C1-C10 alkylene chain, and wherein at least two of the radicals R 1 , R 2 , R 3 and R 4 are independently selected from formula (A), in an amount of 0.1 to 30 phr, preferably 0.5 - 25 phr, particularly preferably 1 - 20 phr, very particularly preferably 3 - 15 phr, preferably with Z = (CH 2 ) Z with z = 2-6, particularly preferably z =3, and R 1 and R 2 are the same and are selected from formula (A) with x = 0-2, preferably x=1, and with w = 0-1, preferably w = 1, and R 3 and R 4are the same and are selected from formula (B) with y = 0-2, preferably y = 0, most preferably use of the at least one processing aid of the formula (I), which is A / ,A / -dimethyl-A / ',A / '-bis(2-hydroxypropyl)-1,3-diamine, in sulfur-crosslinkable rubber mixtures, the vulcanizates obtainable therefrom and the moldings obtainable therefrom, for treating, preferably improving, the conflict of objectives rolling resistance, wet braking and abrasion.

Images