DE102023204801A1 - Compound as an anti-aging agent in rubber compounds and vehicle tires - Google Patents

Abstract

die im vorliegenden Text weiter definiert ist, eine Kautschukmischung enthaltend diese Verbindung, einen Fahrzeugreifen, der die Kautschukmischung in wenigstens einem Bauteil aufweist, ein Verfahren zur Herstellung dieser Verbindung sowie die Verwendung der Verbindung als Alterungsschutzmittel und/oder Antioxidationsmittel.The invention relates to a compound of formula (I)

which is further defined in the present text, a rubber mixture containing this compound, a vehicle tire which has the rubber mixture in at least one component, a process for producing this compound and the use of the compound as an ageing inhibitor and/or antioxidant.

Description

die im vorliegenden Text weiter definiert ist, eine Kautschukmischung enthaltend diese Verbindung, einen Fahrzeugreifen, der die Kautschukmischung in wenigstens einem Bauteil aufweist, ein Verfahren zur Herstellung dieser Verbindung sowie die Verwendung der Verbindung als Alterungsschutz mittel und/oder Antioxidationsmittel.The invention relates to a compound of formula (I)

which is further defined in the present text, a rubber mixture containing this compound, a vehicle tire which has the rubber mixture in at least one component, a process for producing this compound and the use of the compound as an ageing inhibitor and/or antioxidant.

It is known that polymeric compounds, particularly rubbers, are used in vehicle tires and rubber articles that are not vehicle tires (preferably technical rubber articles). Natural rubber (NR), synthetic polymers (e.g. IR, BR, SSBR, ESBR, etc.) but also natural and synthetic oils, fats, lubricants and fuels are subject to oxidation reactions when stored for long periods and often in the target application, which often takes place at higher temperatures. These oxidation reactions have a detrimental effect on the originally desired properties. Depending on the type of polymeric or long-chain compound, these are shortened (up to the point of liquefaction of the article) or there is subsequent, undesirable hardening of the material or article.

Anti-aging agents therefore make a significant contribution to improving the longevity of vehicle tires or rubber articles and corresponding compositions.

Typical anti-aging agents are aromatic amines, such as 6PPD (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine), IPPD (N-isopropyl-N'-phenyl-p-phenylenediamine) or SPPD (N-(1-phenylethyl)-N'-phenyl-p-phenylenediamine). These compounds and anti-aging agents in general can react with oxygen, ozone and/or radicals, preferably alkyl, alkoxy and alkylperoxy radicals, and capture them, thus protecting the polymeric or long-chain compounds from particularly undesirable oxidation and radical reactions. Anti-aging agents that react with or capture ozone are often specifically called "ozone protection agents" or "antiozonants".

The disadvantage of the above-mentioned compounds, however, is the suspicion that they could be carcinogenic and/or harmful to the environment.

Another problem associated with anti-aging agents is undesirable blooming. This is where molecules of the anti-aging agent diffuse to the surface of the tire or rubber article due to their poor solubility in the surrounding polymer matrix and often form a film there that is usually different in color from the rest of the article. In the case of vehicle tires, this typically manifests itself in a brown coloring of the otherwise black sidewall. In addition to the aesthetic disadvantages, this also has disadvantages in terms of the anti-aging effect. Typically, bloomed compounds are removed or removed from the vehicle tire through this process. This reduces the total amount of anti-aging agent and causes further molecules of the anti-aging agent to diffuse towards the surface, so that the protective effect is further reduced.

Anti-aging agents in rubber compositions are well known. For example, US 5,140,055 A Imidazole and benzimidazole derivatives in rubber compounds.

The invention is based on the object of providing novel compounds which can be used in particular as anti-aging agents in vehicle tires and/or other rubber articles which are not vehicle tires. preferably technical rubber articles, with a lower risk potential and sufficient solubility in the respective matrix, for example and in particular in the polymer. This should ensure continued optimal protection against oxygen, radicals and/or (preferably and) ozone while reducing the harmfulness to health and keep the tendency to blooming as low as possible or even prevent it altogether.

At the same time, the compound is intended to achieve an anti-aging effect that is at least equivalent or even improved compared to known aromatic amines, such as 6PPD.

wobei

• - R¹ ausgewählt ist aus der Gruppe bestehend aus
  • - xi) aromatischen Resten, und
  • - xii) aliphatischen C₃- bis C₁₂-Resten,
• - R² und R³ gleich oder verschieden sind und unabhängig voneinander ausgewählt sind aus der Gruppe bestehend aus aliphatischen C₁- bis C₁₂-Resten, aromatischen Resten, Halogen-Resten, Cyano-Resten, Ester-Resten, Keton-Resten, Ether-Resten und Thioether-Resten,
• - m 0 oder 1 oder 2 oder 3 ist,
• - n 0 oder 1 oder 2 oder 3 oder 4 ist, und
• - X ein Ring ist, der aromatisch oder aliphatisch ist.

The object is achieved by the compound according to the invention according to formula (I):

where

• - R ¹ is selected from the group consisting of
  • - xi) aromatic residues, and
  • - xii) aliphatic C ₃ to C ₁₂ residues,
• - R ² and R ³ are the same or different and are independently selected from the group consisting of aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals,
• - m is 0 or 1 or 2 or 3,
• - n is 0 or 1 or 2 or 3 or 4, and
• - X is a ring which is aromatic or aliphatic.

The compound of formula (I) according to the invention is a benzimidazole derivative and has a lower risk potential than known anti-aging agents based on aniline and its degradation products. In vehicle tires and rubber articles that are not vehicle tires (preferably technical rubber articles), this is a decisive advantage, since the rubber ingredients are often released by abrasion or other degradation processes.

The compound of formula (I) according to the invention even has a significantly improved anti-aging effect compared to the known and customary anti-aging agent 6PPD (see examples below), especially in rubber mixtures or vehicle tires.

Preferably, the compound of formula (I) according to the invention is an antiozonant, particularly preferably additionally an antiozonant, i.e. in addition to the ability to react with oxygen and/or radicals (preferably as mentioned above).

The compound of formula (I) according to the invention is preferably suitable as a replacement for 6PPD, the degradation products of which have been proven to be particularly toxic to silver salmon and thus probably also to other aquatic organisms.

The indices m and n describe the number of the corresponding groups R ² and R ³ . If m or n is equal to 0 (zero), the radicals R ² or R ³ are not present and are instead replaced by a hydrogen atom. This is preferably the case independently of one another. Since X is a ring that typically comprises at least several carbon atoms, R ³ is to be regarded as a substituent on this ring and is not present at all (n is zero, instead hydrogen), singly (n is 1) or multiple times (n is 2 to 4) (as is also the case with R ² in the benzimidazole basic structure). Preferably, R ² and R ³ are optional in the compounds according to the invention.

It is also clear to the person skilled in the art that the representation of the linkages of (R ² ) _m and NHR ¹ to the 4 possible carbons in the 6-membered ring of the benzimidazole basic structure and (R ³ ) _n to all possible carbon atoms in the ring X means. These groups are each arranged at any position in the ring assigned to them, except of course not two or more at the same time. In the context of the present invention, the residue NHR ¹ is synonymous with N(H)R ¹ . It means that it is a secondary amine.

In the context of the present invention, the term “C ₃ to C ₁₂ residues” means a residue comprising 3 to 12 carbon atoms.

In the context of the present invention, the basic principle is that the invention should not be tied to a specific mechanism of action or a specific explanation.

The compound of formula (I) according to the invention has sufficient to very good solubility in rubber mixtures, in particular for vehicle tires and rubber articles that are not vehicle tires (in particular technical rubber articles). The solubility is preferably further optimized by suitable selection of the radicals R ² and/or R ^3. This minimizes or even largely prevents unwanted blooming of this compound, which in turn is advantageous for the anti-aging effect. The less anti-aging agent blooms, the less of it is lost intentionally or unintentionally via the surface and the less anti-aging agent diffuses in again. This also has considerable advantages for the environment.

The invention encompasses all preferred embodiments, which are reflected, among other things, in the patent claims. In particular, the invention also encompasses and is deemed to disclose embodiments that result from the combination of different features (also with different gradations in the preference of these features), so that a combination of a first feature designated as "preferred" with a second feature designated as "particularly preferred", for example, is also encompassed and disclosed by the invention.

Furthermore, all statements regarding the features of the compounds according to the invention also apply to the process according to the invention for producing the compounds, the rubber mixture according to the invention containing the compounds and the use according to the invention.

The compound according to the invention:

wobei R¹, R², R³, m, n und X wie vorstehend, vorzugsweise wie im Text als bevorzugt beschrieben, definiert sind.A compound according to the invention is preferred which has the structure according to formula (II):

where R ¹ , R ² , R ³ , m, n and X are as defined above, preferably as described as preferred in the text.

The group X is a ring or a ring structure that is integrated into the overall structure. X is monovalent if n is zero, since in this case the substituent R ³ is hydrogen. X is at least bivalent if n is 1 or greater. In this case, R ³ is bonded to the ring X at least once.

The group X is aromatic (ie its carbon atoms are completely or exclusively aromatic) or aliphatic (ie completely or exclusively aliphatic carbon atoms). In any case, it is necessarily a ring structure.

Preferred is a compound of the formula (I) according to the invention, preferably as described above and/or below as preferred, wherein X comprises 6 carbon atoms, preferably a phenyl radical or a cyclohexyl radical.

What is said in the present text with regard to the compound according to formula (I) particularly preferably also applies mutatis mutandis to the compound according to formula (II) and vice versa. A compound of formula (II) solves the problem underlying the invention particularly well and shows sufficient to good solubility in rubber mixtures, in particular for vehicle tires.

wobei R¹, R², R³, m und n wie vorstehend, vorzugsweise wie im Text als bevorzugt beschrieben, definiert sind.Particularly preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein it has a structure according to formula (la) or (Ib)

where R ¹ , R ² , R ³ , m and n are as defined above, preferably as described as preferred in the text.

In the compound according to formula (la), X is aromatic (i.e., fully aromatic), whereas in the compound according to formula (Ib), X is aliphatic (i.e., fully aliphatic).

wobei R¹, R², R³, m und n wie vorstehend, vorzugsweise wie im Text als bevorzugt beschrieben, definiert sind.Further preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein it has a structure according to formula (IIa) or (IIb)

where R ¹ , R ² , R ³ , m and n are as defined above, preferably as described as preferred in the text.

In the context of the present invention, it is fundamentally the case that n is independent of one another. This means, for example, that n in formula (Ia) or (IIa) is independent of n in formula (Ib) or (IIb). This applies equally to m and to all embodiments of the compound according to the invention.

In the context of the present invention, it also applies in principle that R ² is independent of one another. This means, for example, that R ² in formula (Ia) or (IIa) is independent of R ² in formula (Ib) or (IIb). This applies equally to R ³ and to all embodiments of the compound according to the invention. In addition, R ² and R ³ are basically independent of one another.

In the compound according to the invention, preferably as described above and/or below as preferred, the radicals R ² and R ³ are the same or different and independently selected from the group consisting of aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aliphatic C ₁ to C ₁₂ radicals in R ² and R ³ independently of one another comprise linear partial radicals, branched partial radicals and/or cyclic partial radicals; are preferably linear, branched or cyclic.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aliphatic C ₁ to C ₁₂ radicals in R ² and R ³ are independently saturated or unsaturated, preferably saturated.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aliphatic radicals in R ² and R ³ are aliphatic C ₁ to C ₁₀ radicals, preferably aliphatic C ₁ to C ₈ radicals, more preferably aliphatic C ₁ to C ₆ radicals, particularly preferably aliphatic C ₁ to C ₄ radicals, very particularly preferably aliphatic C ₁ to C ₂ radicals, preferably methyl and/or ethyl.

In some cases, a compound of the invention is preferred, preferably as described above and/or below as preferred, wherein the aliphatic C ₁ to C ₁₂ radicals in R ² and R ³ independently comprise one or more than one halogen substituent, preferably selected from the group consisting of fluorine, chlorine and bromine.

Preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein the aromatic radicals in R ² and R ³ independently of one another comprise 5 to 20 carbon atoms, preferably 6 to 15 carbon atoms, more preferably 6 to 12 carbon atoms, particularly preferably 6 to 10 carbon atoms, most preferably 6 to 8 carbon atoms.

Preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein the aromatic radicals in R ² and R ³ independently of one another comprise one or more than one halogen substituent, preferably selected from the group consisting of fluorine, chlorine and bromine.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the halogen radicals in R ² and R ³ are independently selected from the group consisting of fluorine, chlorine and bromine.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the ester residues, ketone residues, ether residues and thioether residues in R ² and R ³ independently comprise 1 to 20 carbon atoms, preferably 1 to 16 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 9 carbon atoms, more particularly preferably 1 to 7 carbon atoms, most preferably 1 to 5 carbon atoms. In some cases it is preferred that the above upper limits of carbon atoms are combined with at least 2 carbon atoms as a lower limit.

A compound according to the invention is preferred, preferably as described above and/or below as preferred, wherein R ² and R ³ independently of one another comprise a maximum of 12 carbon atoms, preferably 10 carbon atoms, particularly preferably 6 carbon atoms, very particularly preferably 4 carbon atoms. This means, for example, that R ³ comprises a maximum of 10 carbon atoms, while R ² comprises a maximum of 6 carbon atoms.

The above-mentioned radicals R ² and R ³ are particularly preferably already attached by selecting suitable starting compounds.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, where n and m are different or identical.

The number and type of substituents R ² and R ³ , when selected appropriately, have a decisive influence on the solubility of the compound according to the invention within the rubber mixture according to the invention and the vehicle tire according to the invention.

Preference is given to a compound according to the invention in which in formula (Ia) and/or (IIa), m is zero and n is 1, and preferably R ³ is an aliphatic C ₁ to C ₁₂ radical. What has been said above about R ³ and its particularly preferred embodiment preferably applies accordingly. In many cases, such a preferred compound has improved solubility in the rubber mixture according to the invention and thus solves the underlying problem particularly well. In particular, undesirable blooming is further reduced or completely prevented.

A compound according to the invention is preferred in which m and n are zero in formula (Ib) and/or (IIb). The cyclohexyl group (for X) already present in this compound also ensures improved solubility in the rubber mixture according to the invention. In this case, additional substituents in the form of R ³ can preferably be dispensed with.

wobei

• - R¹ ein aliphatischer C₃- bis C₁₂-Rest ist, vorzugsweise ein C₄ bis C₈ Alkyl,
• - R² und R³ gleich oder verschieden sind und unabhängig voneinander ausgewählt sind aus der Gruppe bestehend aus

For the purposes of the present invention, a compound according to the invention is particularly preferred, wherein it has the structure according to formula (IIa-I):

where

• - R ¹ is an aliphatic C ₃ to C ₁₂ radical, preferably a C ₄ to C ₈ alkyl,
• - R ² and R ³ are the same or different and are independently selected from the group consisting of

Hydrogen, aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals; preferably hydrogen and aliphatic C ₁ to C ₁₂ radicals.

What has been said above (and also below) regarding the compound according to the invention and its preferred embodiments preferably also applies mutatis mutandis to the preferred compound of the formula (IIa-I).

• - xi) aromatischen Resten, und
• - xii) aliphatischen C₃- bis C₁₂-Resten.

In the compound according to the invention, the radical R ¹ is selected from the group consisting of

• - xi) aromatic residues, and
• - xii) aliphatic C ₃ to C ₁₂ residues.

In some cases, preference is given to a compound according to the invention, preferably as described above and/or below as preferred, where the aromatic radicals in xi) comprise a substituent selected from the group consisting of alkyl radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals; particularly preferably alkyl radicals, ester radicals, ketone radicals, ether radicals and thioether radicals. In other cases and particularly preferred, the aromatic radicals in xi) do not carry any of the abovementioned substituents, preferably are not substituted at all. The substituent is preferably in the meta or para position.

It is particularly preferred that the substituent is not in the ortho position. This is particularly advantageous for the longevity of the anti-aging agent.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aromatic radicals in xi) comprise 5 to 20 carbon atoms, preferably 6 to 15 carbon atoms, more preferably 6 to 10 carbon atoms, most preferably 6 to 8 carbon atoms.

Particularly preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein the aromatic radicals in xi) comprise phenyl radicals (ie -C ₆ H ₅ ), alpha-methylbenzyl (ie - CH ₂ (CH ₃ )-C ₆ H ₅ ), and/or benzyl radicals (ie -CH ₂ -C ₆ H ₅ ), particularly preferably phenyl radicals.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aliphatic C ₃ to C ₁₂ radicals in xii) comprise linear partial radicals, branched partial radicals and/or cyclic partial radicals; are preferably linear, branched or cyclic, most preferably branched.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein the aliphatic C ₃ to C ₁₂ radicals in xii) are saturated or unsaturated, preferably saturated.

Particularly preferred is a compound according to the invention, preferably as described above and/or below as preferred, wherein in xii) the aliphatic radicals are aliphatic C ₃ to C ₁₀ radicals, preferably aliphatic C ₄ to C ₈ radicals, more preferably aliphatic C ₅ to C ₇ radicals.

Preference is given to a compound according to the invention, preferably as described above and/or below as preferred, wherein R ¹ comprises a tertiary carbon atom with which it is bonded to the nitrogen atom (N). The nitrogen atom (N) is preferably a secondary nitrogen atom.

In the context of the present invention, the term "tertiary carbon atom" is understood to mean a carbon atom that has only one attached hydrogen atom. This results in a particularly good protective effect compared to secondary and quaternary carbon atoms, preferably in rubber mixtures (particularly preferred for vehicle tires and/or other rubber articles that are not vehicle tires (particularly technical rubber articles)). In particular, optimized reactivity is achieved in connection with the mechanisms relevant to ageing protection, while undesirable side reactions are avoided.

Particularly preferred is a compound according to the invention in which R ¹ is a branched or cyclic alkyl radical, preferably comprising 3 to 12 carbon atoms, preferably comprising 3 to 8 carbon atoms, particularly preferably comprising 4 to 7 carbon atoms. These are particularly preferably saturated. Cyclic alkyl radicals preferably comprise at least 5 carbon atoms, preferably at least 6. This minimum number is preferably combined with the aforementioned upper limits of carbon atoms.

Very particularly preferred is a compound according to the invention, preferably as described above and/or below as preferred, where R ¹ is 1,3-dimethylbutyl, phenyl, benzyl or cyclohexyl, preferably 1,3-dimethylbutyl. This achieves a particularly good protective effect in rubber mixtures, particularly preferably for vehicle tires and rubber articles which are not vehicle tires (preferably technical rubber articles).

A compound according to the invention is particularly preferred which has the structure according to formula (III):

The compound according to formula (III) has sufficient solubility in polymers, preferably in rubber mixtures, particularly preferably in rubber mixtures for vehicle tires and rubber articles that are not vehicle tires (preferably technical rubber articles). Furthermore, the compound according to formula (III) can be prepared comparatively easily and in an energy- and cost-saving manner and shows a dramatically improved protective effect compared to 6PPD (see examples below). The compound according to formula (III) according to the invention is also referred to as N-(1,3-dimethylbutylamino)-2-phenyl-1H-benzo[d]imidazol-6-amine according to IPUAC.

Rubber mixture comprising a compound according to formula (1):

The present invention also relates to a rubber mixture containing the compound according to the invention as described above (preferably as described above and/or below as preferred), preferably comprising one or more than one diene rubber. The rubber mixture comprises one or more than one compound according to the invention, wherein preferably at least one rubber is a diene rubber.

What has been said above regarding the compound according to the invention, in particular as described above as preferred, preferably also applies mutatis mutandis to the rubber mixture according to the invention.

The rubber mixture according to the invention therefore contains at least one rubber. The rubber mixture according to the invention is in principle any rubber mixture in which the compounds according to the invention act as anti-aging agents and/or antiozonants with lower toxicity. The rubber mixture according to the invention comprises one or more than one rubber.

Particularly preferred is a rubber mixture according to the invention, preferably as described above and/or below as preferred, comprising one or more than one compound according to the invention, preferably as described above as preferred, particularly preferably selected from the group consisting of compounds according to formula (I), (Ia), (Ib), (II), (Ila), (IIb), (IIa-I) and (III), particularly preferably comprising compounds according to formula (IIa-I) and/or (III).

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising one or more than one compound according to the invention (preferably as described above as preferred), these being the only benzimidazole compounds compounds in the rubber mixture, particularly preferably the compound of formula (IIa-I) or (III) are the only benzimidazole compounds in the rubber mixture.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising a total amount of the compound according to the invention of 0.1 to 10 phr, preferably of 0.3 to 8 phr, more preferably of 0.6 to 6 phr, particularly preferably of 0.8 to 4.5 phr, most preferably of 1 to 3 phr.

The term phr (parts per hundred parts of rubber by weight) used in the context of the present invention is the quantity specification for mixture recipes commonly used in the rubber industry. The dosage of the parts by weight is based on 100 parts by weight of the total mass of all high molecular weight (M _w greater than 20,000 g/mol) rubbers present in the mixture.

The rubber mixture according to the invention, preferably as described above and/or below as preferred, preferably comprises one or more than one diene rubber. Diene rubbers are typically rubbers that are formed by polymerization or copolymerization of dienes and/or cycloalkenes and thus have C=C double bonds either in the main chain or in the side groups.

Preference is given to a rubber mixture according to the invention, preferably as described above and/or below as preferred, wherein the diene rubber is selected from the group consisting of natural polyisoprene (NR), synthetic polyisoprene (IR), epoxidized polyisoprene (ENR), butadiene rubber (BR), butadiene-isoprene rubber, solution-polymerized styrene-butadiene rubber (SSBR), emulsion-polymerized styrene-butadiene rubber (ESBR), styrene-isoprene rubber, liquid rubbers with a molecular weight M _w of greater than 20,000 g/mol, butyl rubber (IIR), halobutyl rubber (XIIR), polynorbornene, isoprene-isobutylene copolymer, ethylene-propylene-diene rubber, nitrile rubber, Chloroprene rubber, acrylate rubber, fluororubber, silicone rubber, polysulfide rubber, epichlorohydrin rubber, styrene-isoprene-butadiene terpolymer, hydrogenated acrylonitrile-butadiene rubber and hydrogenated styrene-butadiene rubber.

In the context of the present invention, the term "natural rubber" and "natural rubber", both terms having an identical scope of meaning, means naturally occurring rubber obtained from Hevea rubber trees and/or "non-Hevea" sources. Preferred non-Hevea sources are guayule shrubs and dandelions. A particularly preferred dandelion is TKS (Taraxacum kok-saghyz; Russian dandelion).

Particularly preferred is a rubber mixture according to the invention, preferably as described above and/or below as preferred, wherein the diene rubber is selected from the group consisting of natural polyisoprene (NR), synthetic polyisoprene (IR), butadiene rubber (BR), solution-polymerized styrene-butadiene rubber (SSBR), emulsion-polymerized styrene-butadiene rubber (ESBR), butyl rubber (IIR) and halobutyl rubber (XIIR).

Very particularly preferred is a rubber mixture according to the invention, preferably as described above and/or below as preferred, wherein the diene rubber is selected from the group consisting of natural polyisoprene (NR), synthetic polyisoprene (IR), butadiene rubber (BR), solution-polymerized styrene-butadiene rubber (SSBR) and emulsion-polymerized styrene-butadiene rubber (ESBR).

Nitrile rubber, hydrogenated acrylonitrile butadiene rubber, chloroprene rubber, butyl rubber (IIR), halobutyl rubber (XIIR) and/or ethylene-propylene-diene rubber are preferably used in the manufacture of rubber articles that are not vehicle tires (but are otherwise typically considered technical rubber articles), preferably for belts, straps, hoses, bands and/or shoe soles. The mixture compositions known to the person skilled in the art for these rubbers - special with regard to fillers, plasticizers, vulcanization systems and additives - are preferred.

Polyisoprene preferably comprises cis-1,4-polyisoprene and/or 3,4-polyisoprene. This preferably applies regardless of whether it is natural or synthetic polyisoprene. Preference is given to cis-1,4-polyisoprene, with a particularly preferred cis-1,4 content of greater than 90% by weight. Such a polyisoprene is preferably prepared by stereospecific polymerization in solution using Ziegler-Natta catalysts or using finely divided lithium alkylene. Furthermore, natural rubber (NR) is also such a cis-1,4 polyisoprene. Natural rubber (NR) comprising cis-1,4 polyisoprene is therefore particularly preferred, preferably with a cis-1,4 content of greater than or equal to 99% by weight.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising one or more than one natural polyisoprene (NR) and one or more than one synthetic polyisoprene (IR). Thus, a mixture of polyisoprene is preferably present.

In some cases, a rubber mixture according to the invention is particularly preferred, preferably as described above and/or below as preferred, comprising one or more than one natural polyisoprene (NR), preferably in a total amount of 56 to 130 phr, particularly preferably 80 to 120 phr, very particularly preferably 90 to 110 phr, more preferably 95 to 100 phr. Such a rubber mixture exhibits in particular optimized tear properties and abrasion properties while at the same time having good processability and reversion stability. Another preferred total amount is in the range of 56 to 100 phr, preferably 80 to 100 phr, more preferably 90 to 100 phr.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising one or more than one natural polyisoprene (NR), the total amount of which is significantly less than 100 phr. In these cases, the rubber mixture additionally comprises one or more than one rubber other than natural polyisoprene, preferably another diene rubber, particularly preferably selected from the group consisting of synthetic polyisoprene (IR), butadiene rubber (BR), solution-polymerized styrene-butadiene rubber (SSBR) and emulsion-polymerized styrene-butadiene rubber (ESBR). Particularly preferred in these cases is a rubber mixture according to the invention comprising one or more than one natural polyisoprene (NR) in a total amount of 5 to 55 phr, preferably from 5 to 35 phr, more preferably from 5 to 25 phr, most preferably from 5 to 20 phr. Such a rubber compound shows in particular good processability and reversion stability as well as optimized tear properties and optimal rolling resistance behavior.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising at least one butadiene rubber (BR, polybutadiene). A butadiene rubber comprising a high-cis and/or a low-cis type is preferred, with polybutadiene with a cis content greater than or equal to 90% by weight being referred to as a high-cis type and polybutadiene with a cis content less than 90% by weight being referred to as a low-cis type. A particularly preferred low-cis type comprises Li-BR (lithium-catalyzed butadiene rubber), preferably with a cis content of 20 to 50% by weight. A high-cis type is particularly preferred, since this achieves particularly good properties, in particular a low hysteresis of the rubber mixture.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, wherein the butadiene rubber is end-group functionalized by means of one or more than one functional group and/or functionalized along the polymer chains. Preferably, the one or more than one functional group is independently selected from the group consisting of hydroxy groups, ethoxy groups, epoxy groups, siloxane groups, amino groups, aminosiloxane groups, carboxy groups, phthalocyanine groups and silane sulfide groups. However, the selection of the functional group is preferably not limited to the above groups. In some cases, the functional group preferably comprises one or more metals.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising the one or more butadiene rubbers in a total amount of 10 to 80 phr, preferably 12 to 50 phr, particularly preferably 15 to 40 phr. This achieves particularly good tear and abrasion properties of the rubber mixture according to the invention and optimum braking behavior.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising at least one styrene-butadiene rubber (styrene-butadiene copolymer). Preference is given to a styrene-butadiene rubber comprising one or more than one solution-polymerized styrene-butadiene rubber (SSBR) and/or one or more than one emulsion-polymerized styrene-butadiene rubber (ESBR). In the context of the present invention, the terms “styrene-butadiene rubber” and “styrene-butadiene copolymer” are used synonymously. In some In some cases, a rubber mixture according to the invention is preferred, wherein the styrene-butadiene rubber is end-group functionalized by means of one or more than one functional group and/or functionalized along the polymer chains. What has been said above about butadiene rubber applies accordingly to preferred functional groups.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising the at least one styrene-butadiene rubber (SSBR) in a total amount of 10 to 80 phr, preferably 30 to 75 phr, particularly preferably 50 to 70 phr. A rubber mixture according to the invention is particularly preferred, comprising one or more than one solution-polymerized styrene-butadiene rubber (SSBR), which is also present in a total amount of 10 to 80 phr, preferably 30 to 75 phr, particularly preferably 50 to 70 phr. This achieves particularly good rolling resistance properties of the rubber mixture according to the invention. The solution-polymerized styrene-butadiene rubber (SSBR) is particularly preferably used in combination with one or more than one other rubber. This typically results in an improved and more balanced property profile.

In addition to one or more than one compound according to the invention and at least one rubber, the rubber mixture according to the invention preferably additionally comprises ingredients, preferably at least one filler.

Preferably, a rubber mixture according to the invention, preferably as described above and/or below as preferred, additionally comprises one or more than one filler, preferably in a total amount of 30 to 500 phr, preferably 50 to 400 phr, more preferably 80 to 300 phr. A particularly preferred filler is a reinforcing filler, particularly preferably selected from the group consisting of carbon blacks and silicon dioxides.

In principle, all types of carbon black known to the person skilled in the art can be used as carbon black. The carbon black is preferably selected from the group consisting of industrial carbon black and pyrolysis carbon black, with industrial carbon black being preferred.

Preferably, the carbon black has an iodine number according to ASTM D 1510 (also referred to as iodine adsorption number) in a range from 30 to 250 g/kg, preferably from 35 to 215 g/kg, particularly preferably from 40 to 180 g/kg, and most preferably from 45 to 140 g/kg, and/or a DBP number according to ASTM D 2414 in a range from 30 to 200 ml/100 g, preferably from 70 to 170 ml/100 g, particularly preferably from 90 to 140 ml/100 g. The DBP number according to ASTM D 2414 determines the specific absorption volume of a carbon black or a light filler by means of dibutyl phthalate. The use of such a carbon black in the rubber mixture according to the invention, in particular for vehicle tires, usually ensures the best possible compromise between abrasion resistance and heat build-up, which in turn influences the ecologically relevant rolling resistance. A carbon black with an iodine number in the range from 80 to 110 g/kg and a DBP number in the range from 100 to 130 ml/100 g is particularly preferred. A carbon black of the N339 type is very particularly preferred.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, wherein the carbon black is present in the rubber mixture in a total amount in the range from 0.1 to 60 phr, preferably from 3 to 40 phr, particularly preferably from 4 to 30 phr, most preferably from 5 to 15 phr. In these amounts, the carbon black is typically present as a supplementary filler in combination with a main filler, preferably one or more silicon dioxide, particularly preferably silica.

In other cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, wherein the carbon black is present in the rubber mixture in a total amount in the range from 30 to 300 phr, preferably from 35 to 200 phr, particularly preferably from 40 to 100 phr. In these amounts, carbon black is contained in particular as the sole or as the main filler (more than 50% by weight based on the total amount of filler; preferably in combination with comparatively small amounts of silica).

Preferably, the silicon dioxide is amorphous silicon dioxide and/or fumed silicon dioxide. A particularly preferred amorphous silicon dioxide comprises precipitated silica, also referred to as precipitated silicon dioxide. In the context of the present invention, the terms "silica" and "silica" have the same meaning and are therefore synonymous.

Particularly preferred is amorphous silicon dioxide, preferably precipitated silica, with a nitrogen surface area (BET surface area) (according to DIN ISO 9277 and DIN 66132) in the range from 35 to 400 m ² /g, preferably from 50 to 350 m ² /g, particularly preferably from 85 to 320 m ² /g, very particularly preferably from 120 to 235 m ² /g, and/or (preferably and) with a CTAB surface area (according to ASTM D 3765) in the range from 30 to 400 m ² /g, preferably from 50 to 330 m ² /g, particularly preferably from 80 to 300 m ² /g, very particularly preferably from 115 to 200 m ² /g. Such silicon dioxide leads, for example, to... In rubber mixtures for tire treads, for example, this leads to particularly good physical properties of the vulcanizates. In addition, this can result in advantages in mixture processing due to a reduction in mixing time while maintaining the same product properties, which leads to improved productivity. Particularly preferred is a silica of the type Ultrasil® VN3 (trade name) from Evonik, as well as highly dispersible silicas (so-called HD silicas). Preferred highly dispersible silicas include Zeosil® 1165 MP from Solvay.

In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising at least one silica, preferably in a total amount in the range from 30 to 500 phr, more preferably from 50 to 400 phr, particularly preferably from 80 to 300 phr. In these amounts, silica is contained in particular as the sole or as the main filler (more than 50% by weight based on the total amount of filler; preferably in combination with comparatively small amounts of carbon black).

In some cases, a rubber mixture according to the invention is particularly preferred, preferably as described above and/or below as preferred, comprising at least one silica, preferably in a total amount in the range from 5 to 100 phr, more preferably from 7 to 80 phr, particularly preferably from 10 to 60 phr. In these amounts, silica is typically contained as a supplementary filler in combination with a main filler, preferably a carbon black.

Particularly preferred is a rubber mixture according to the invention, preferably as described above and/or below as preferred, comprising at least one silica and at least one carbon black, wherein the total amount of silica is in the range from 50 to 300 phr, preferably from 80 to 200 phr, and the total amount of carbon black is in the range from 5 to 60 phr, preferably from 7 to 40 phr.

The rubber mixture according to the invention preferably comprises, preferably as described above and/or below as preferred, additional fillers, i.e. which are not or do not comprise carbon blacks, silicon dioxides or silicas. These additional fillers preferably also comprise reinforcing fillers and/or non-reinforcing fillers.

Preferred non-reinforcing fillers include aluminosilicates, kaolin, chalk, starch, magnesium oxide, titanium dioxide, rubber gels and/or fibers. Preferred fibers include aramid fibers, glass fibers, carbon fibers and/or cellulose fibers.

Preferred reinforcing fillers include carbon nanotubes, graphite, graphene and/or so-called “carbon-silica dual-phase fillers”. The carbon nanotubes preferably comprise unmodified carbon nanotubes and/or carbon nanotubes modified with functional groups, with preferred functional groups being selected from the group consisting of hydroxyl, carboxy and carbonyl groups.

In the context of the present invention, zinc oxide is not one of the fillers within the meaning of the present invention.

A rubber mixture according to the invention is preferably as described above and/or below as preferred, comprising one or more than one further additive. These are typically conventional additives in the typical amounts which are preferably added in at least one basic mixing stage during the production of the rubber mixture.

1. a) Alterungsschutzmittel, die aus dem Stand der Technik bekannt sind und die keine erfindungsgemäße Verbindung der Formel (I), bzw. sonstige erfindungsgemäße Verbindungen sind; vorzugsweise umfassend para-Phenylendiamine und/oder Dihydrochinoline; besonders bevorzugt ausgewählt aus der Gruppe bestehend aus N-Phenyl-N'-(1,3-dimethylbutyl)-p-phenylendiamin (6PPD), N,N'-Diphenyl-p-phenylendiamin (DPPD), N-(1-phenylethyl)-N'-phenyl-p-phenylendiamin (SPPD), N,N'-Ditolyl-p-phenylendiamin (DTPD), N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylendiamin (7PPD), N-Isopropyl-N'-phenyl-p-phenylendiamin (IPPD), und 2,2,4-Trimethyl-1,2-dihydrochinolin (TMQ);
2. b) einen Aktivator; vorzugsweise umfassend Zinkverbindungen (inklusive Zinkkomplexe) und/oder Fettsäuren; besonders bevorzugt umfassend Zinkoxid, Stearinsäure und/oder Zinkethylhexanoat;
3. c) Agenzien für die Anbindung von Füllstoffen (insbesondere für Ruß und Kieselsäure); vorzugsweise umfassend S-(3-Aminopropyl)-Thioschwefelsäure, deren Metallsalze (besonders für die Anbindung an Ruß) und/oder Silan-Kupplungsagenzien (besonders für die Anbindung an Siliciumdioxid, insbesondere an Kieselsäure);
4. d) Ozonschutzwachse;
5. e) Harze; vorzugsweise Klebharze;
6. f) Mastikationshilfsmittel; vorzugsweise umfassend 2,2'-Dibenzamidodiphenyldisulfid (DBD);
7. g) Prozesshilfsmittel; vorzugsweise umfassend Fettsäureester und/oder Metallseifen, wobei bevorzugte Metallseifen Zinkseifen und/oder Calciumseifen umfassen; und/oder
8. h) Weichmacher; vorzugsweise umfassend Öle (vorzugsweise umfassend aromatische, naphthenische und/oder paraffinische Mineralöle), Harze und/oder Flüssig-Polymere; besonders bevorzugt umfassend MES (mild extraction solvate), DAE (Destillated Aromatic Extracts), RAE (Residual Aromatic Extract), TDAE (treated distillate aromatic extract), Rubber-to-Liquid-Öle (RTL), Biomass-to-Liquid-Öle (BTL) (vorzugsweise mit einem Gehalt an polycyclischen Aromaten von weniger als 3 Gew.-% gemäß Methode IP 346), Triglyceride (vorzugsweise Rapsöl), ein Faktis, Kohlenwasserstoffharze, und/oder Flüssig-Polymere mit einem mittleren Molekulargewicht (Bestimmung per GPC = gel permeation chromatography, in Anlehnung an BS ISO 11344:2004) zwischen 500 und 20000 g/mol. Bei der Verwendung von Mineralöl ist dieses bevorzugt ausgewählt aus der Gruppe bestehend aus DAE (Destillated Aromatic Extracts), RAE (Residual Aromatic Extract), TDAE (Treated Destillated Aromatic Extracts), MES (Mild Extracted Solvents) und naphthenischen Ölen.

Preferably, the one or more further additives comprise:

1. a) Anti-aging agents which are known from the prior art and which are not a compound of the formula (I) according to the invention or other compounds according to the invention; preferably comprising para-phenylenediamines and/or dihydroquinolines; particularly preferably selected from the group consisting of N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD), N,N'-diphenyl-p-phenylenediamine (DPPD), N-(1-phenylethyl)-N'-phenyl-p-phenylenediamine (SPPD), N,N'-ditolyl-p-phenylene diamine (DTPD), N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylenediamine (7PPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ);
2. b) an activator; preferably comprising zinc compounds (including zinc complexes) and/or fatty acids; particularly preferably comprising zinc oxide, stearic acid and/or zinc ethylhexanoate;
3. c) agents for the binding of fillers (in particular for carbon black and silica); preferably comprising S-(3-aminopropyl)-thiosulphuric acid, its metal salts (in particular for the binding to carbon black) and/or silane coupling agents (in particular for the binding to silicon dioxide, in particular to silica);
4. (d) antiozone waxes;
5. e) resins, preferably adhesive resins;
6. f) mastication aids; preferably comprising 2,2'-dibenzamidodiphenyl disulfide (DBD);
7. g) processing aids; preferably comprising fatty acid esters and/or metal soaps, preferred metal soaps comprising zinc soaps and/or calcium soaps; and/or
8. h) plasticizers; preferably comprising oils (preferably comprising aromatic, naphthenic and/or paraffinic mineral oils), resins and/or liquid polymers; particularly preferably comprising MES (mild extraction solvate), DAE (distilled aromatic extracts), RAE (residual aromatic extract), TDAE (treated distillate aromatic extract), rubber-to-liquid oils (RTL), biomass-to-liquid oils (BTL) (preferably with a polycyclic aromatics content of less than 3% by weight according to method IP 346), triglycerides (preferably rapeseed oil), a factice, hydrocarbon resins, and/or liquid polymers with an average molecular weight (determined by GPC = gel permeation chromatography, based on BS ISO 11344:2004) between 500 and 20,000 g/mol. When using mineral oil, it is preferably selected from the group consisting of DAE (Distillated Aromatic Extracts), RAE (Residual Aromatic Extract), TDAE (Treated Distillated Aromatic Extracts), MES (Mild Extracted Solvents) and naphthenic oils.

Particularly preferred in most cases is a rubber mixture according to the invention, preferably as described above and/or below as preferred, which is essentially free from, preferably not comprising, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD), N,N'-diphenyl-p-phenylenediamine (DPPD), N-(1-phenylethyl)-N'-phenyl-p-phenylenediamine (SPPD), N,N'-ditolyl-p-phenylenediamine (DTPD), N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylenediamine (7PPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and optionally additionally from 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ); more preferably essentially free from, preferably not comprising, para-phenylenediamines and optionally additionally from dihydroquinolines; most preferably, it is essentially free from, preferably not comprising, an aging inhibitor which is not a compound according to the invention (i.e., aging inhibitors known from the prior art and customary). It is therefore particularly preferred that the rubber mixture according to the invention contains one or more than one compound according to the invention as the only aging inhibitor, preferably as described above as preferred. In the context of the present invention, "essentially free from" means an upper limit of 0.1 phr, preferably a total amount in the range from 0 phr to 0.1 phr, particularly preferably from 0.0001 phr to 0.1 phr. The amount is particularly preferably zero (0), i.e., "not comprising". With these very preferably small amounts, including zero (0) phr, it is possible to achieve a comparable protective effect with significantly lower toxicity. The compound according to the invention replaces the para-phenylenediamines mentioned which are known from the prior art and typically used. In some other cases, a rubber mixture according to the invention is preferred in which at least some of the anti-aging agent which is not a compound according to the invention (particularly para-phenylenediamines) is replaced by one or more than one compound according to the invention, preferably 50% by weight or more. In this way, the advantage according to the invention is at least partially achieved, even if not yet to the optimum extent.

As defined above, the additional absence of dihydroquinolines, preferably 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ), is optional, i.e. desired in some cases, not desired in others. In some cases, a rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising (regardless of whether para-phenylenediamines are present or not) one or more than one dihydroquinoline, preferably 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ). Preferably, the dihydroquinoline, preferably the 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ), is present in a total amount in the range of 0.1 to 3 phr in the rubber mixture according to the invention, preferably from 0.5 to 1.5 phr.

Antiozone waxes (see d) above) are considered separately and are preferably contained in the rubber mixture according to the invention, regardless of whether ageing inhibitors according to a) are contained or not.

The silane coupling agents (see c) above) are preferably all types known to the person skilled in the art. Preferably, the rubber mixture according to the invention comprises one or more than one silane coupling agent, preferably as described above and/or below as preferred. In some cases, the rubber mixture according to the invention preferably comprises a mixture of different silanes.

Silane coupling agents react with the surface silanol groups of silicon dioxide (especially silica) or other polar groups, either during mixing of the rubber or rubber compound (in situ) or before adding it to the rubber during pretreatment (premodification).

Preferred silane coupling agents include bifunctional organosilanes which have at least one alkoxy, cycloalkoxy or phenoxy group as a leaving group on the silicon atom and have as additional functionality a group which (optionally after cleavage) can enter into a chemical reaction with the double bonds of the polymer. Preferred groups include -SCN, -SH, -NH ₂ and/or -S _x - (where x = 2 to 8). Silanes with an -SH group are typically also referred to as mercaptosilanes. Preferred mercaptosilanes include blocked mercaptosilanes, preferably according to WO 99/09036 A1 .

Particularly preferred silane coupling agents include 3-mercaptopropyltriethoxysilane, 3-thiocyanatopropyltrimethoxysilane, 3,3'-bis(triethoxysilylpropyl)polysulfides having 2 to 8 sulfur atoms (particularly preferably 3,3'-bis(triethoxysilylpropyl)tetrasulfide (TESPT) and/or its disulfide (TESPD)) and/or mixtures of the sulfides, each preferably having a different number of sulfur atoms. In some cases, TESPT is preferred, particularly preferably as a mixture with industrial carbon black (trade name X50S® from Evonik).

Preferred silane coupling agents include, additionally or alternatively, those according to WO 2008/083241 A1 , WO 2008/083242 A1 , WO 2008/083243 A1 and/or WO 2008/083244 A1 . Further preferred silane coupling agents, additionally or alternatively, include silanes (preferably 3-octanoylthio-1-propyltriethoxysilane) sold under the name NXT in various variants by Momentive, USA, and/or silanes sold under the name VP Si 363® by Evonik Industries.

Preference is given to a rubber mixture according to the invention, preferably as described above and/or below as preferred, wherein the one or more further additives are included in a total amount in the range from 3 to 150 phr, preferably from 4 to 100 phr, more preferably from 5 to 80 phr.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising one or more than one activator (see b) above); preferably a zinc compound, particularly preferably zinc oxide. There is preferably no restriction with regard to the types of zinc oxide. Granules and/or powder are preferred. The zinc oxide preferably has a BET surface area of up to 100 m ² /g, preferably in a range from 1 to 100 m ² /g. In some cases, a zinc oxide is preferred, the BET surface area being less than 10 m ² /g. In other cases, a zinc oxide is preferred, the BET surface area being in the range from 10 to 100 m ² /g; so-called “nano-zinc oxides” are particularly preferred.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, wherein it is vulcanized or partially vulcanized, preferably vulcanized. This means that it is preferably used in vulcanized or at least partially vulcanized form, particularly preferably in a vehicle tire or in rubber articles that are not vehicle tires (preferably technical rubber articles). In the context of the present invention, the terms "vulcanized" and "crosslinked" are used synonymously. The rubber mixture according to the invention is therefore preferably a crosslinked rubber mixture. However, it is of course clear to the person skilled in the art that the rubber mixture is typically not vulcanized until the relevant processing.

The vulcanization or vulcanization of the rubber mixture according to the invention is preferably carried out in the presence of sulfur and/or sulfur donors, preferably with the assistance of vulcanization accelerators, whereby preferably some vulcanization accelerators are also sulfur donors.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising sulfur and/or one or more than one sulfur donor. There are no particular restrictions with regard to the sulfur donors, so that in principle all sulfur donors known to the person skilled in the art can be considered, as long as they provide sulfur in an appropriate form under the existing conditions.

Preferably, a rubber mixture according to the invention comprises (alternatively or in addition to a sulfur donor) one or more than one vulcanization accelerator.

Preferred vulcanization accelerators include thiazole accelerators, mercapto accelerators, sulfenamide accelerators, thiocarbamate accelerators, thiuram accelerators, thiophosphate accelerators, thiourea accelerators, xanthate accelerators and/or guanidine accelerators. Particularly preferred is one or more than one sulfenamide accelerator and/or one or more than one guanidine accelerator, most particularly one or more than one accelerator selected from the group consisting of N-cyclohexyl-2-benzothiazolesufenamide (CBS), N,N-dicyclohexylbenzothiazole-2-sulfenamide (DCBS), benzothiazyl-2-sulfenemorpholide (MBS), N-tert-butyl-2-benzothiazylsulfenamide (TBBS) and diphenylguanidine (DPG).

A rubber mixture according to the invention, preferably as described above and/or below as preferred, preferably comprises one or more than one vulcanization retarder. The presence of a vulcanization retarder contributes, for example, to a better balanced vulcanization process.

The rubber mixture according to the invention is preferably produced or provided, particularly preferably produced. This is preferably done according to processes customary in the rubber industry, in which a base mixture with all components except (i.e. minus) the vulcanization system is first provided in one or more mixing stages, the vulcanization system comprising the sulfur and the vulcanization-influencing compounds, i.e. preferably the total amount of sulfur, sulfur donor, vulcanization accelerator and vulcanization retarder. By adding the vulcanization system in a final mixing stage, a finished mixture is produced, which is preferably further processed by extrusion and/or calendering and brought into the desired shape. The shape achieved in this way preferably determines the subsequent use, such as in a vehicle tire.

A rubber mixture according to the invention is preferably used in a vulcanizate.

Further preferred is a rubber mixture according to the invention for use in a vehicle tire, preferably in an outer or inner component of a vehicle tire, preferably an outer component.

A rubber mixture according to the invention is preferred, preferably as described above and/or below as preferred, comprising one or more than one strength carrier, preferably comprising fibers, fabrics and/or cords.

Vehicle tires comprising the rubber mixture according to the invention:

The present invention also relates to a vehicle tire, preferably a pneumatic vehicle tire, which has the rubber mixture according to the invention as described above, preferably as described above as preferred, in at least one component, preferably in at least one outer component, wherein the outer component is preferably a tread, a sidewall and/or a horn profile.

What has been said above regarding the compound according to the invention and the rubber mixture according to the invention, each including preferred embodiments, preferably also applies mutatis mutandis to the vehicle tire according to the invention.

The vehicle tire according to the invention is preferably vulcanized, ie not a vehicle tire blank. The vulcanized vehicle tire preferably has a vulcanizate of at least one rubber mixture according to the invention in at least one component. It is known to the person skilled in the art that most compounds, such as the rubbers contained, are present in a chemically modified form either after mixing or only after vulcanization, or can be present at all.

The vehicle tire according to the invention, preferably as described above and/or below as preferred, preferably comprises a pneumatic vehicle tire and/or a solid rubber tire.

Preferably, the vehicle tire according to the invention, preferably as described above and/or below as preferred, is selected from the group consisting of industrial and construction vehicle tires, truck, car and two-wheel tires.

Particularly preferred is a vehicle tire according to the invention, preferably as described above and/or below as preferred, which has the rubber mixture according to the invention in two, three or more than three components.

Use of the compound according to the invention and rubber mixture according to the invention:

The present invention relates very generally to a use of the compound according to the invention, preferably as described above as preferred, as an age inhibitor and/or (preferably and) antioxidant in a rubber mixture, preferably in a rubber mixture according to the invention (preferably as described above as preferred).

• - Fahrzeugreifen, besonders bevorzugt Fahrzeugluftreifen;
• - Gummiartikeln, die keine Fahrzeugreifen sind, besonders bevorzugt ausgewählt aus der Gruppe bestehend aus Luftfedern, Bälgen, Bändern, Gurten, Riemen, Schläuchen, Profilen, Dichtungen, Membranen, taktilen Sensoren für medizinische Anwendungen, taktilen Sensoren für Roboteranwendungen, Schuhsohlen und Teilen einer Schuhsohle;
• - Ölen und/oder Fetten; und/oder
• - Kraft- und/oder Schmierstoffen.

The present invention also relates to a use of the compound according to the invention, preferably as described above and/or below as preferred, as an anti-aging agent and/or antioxidant (preferably as an anti-aging agent), preferably in

• - vehicle tires, particularly preferably pneumatic vehicle tires;
• - rubber articles which are not vehicle tires, particularly preferably selected from the group consisting of air springs, bellows, bands, belts, straps, hoses, profiles, seals, membranes, tactile sensors for medical applications, tactile sensors for robot applications, shoe soles and parts of a shoe sole;
• - oils and/or fats; and/or
• - fuels and/or lubricants.

What has been said above regarding the compound according to the invention (including preferred embodiments) and the rubber mixture according to the invention (including preferred embodiments) preferably also applies mutatis mutandis to the use according to the invention as an anti-aging agent and/or antioxidant.

Preferred belts include conveyor belts.

In some cases, the use of the compound according to the invention as an ageing inhibitor and/or antioxidant in oils, fats, fuels and/or lubricants is preferred, particularly preferably in connection with use for engines.

• - Fahrzeugreifens, vorzugsweise eines Fahrzeugluftreifens; und/oder
• - Gummiartikels, der kein Fahrzeugreifen ist, besonders bevorzugt ausgewählt aus der Gruppe bestehend aus Luftfedern, Bälgen, Bändern, Gurten, Riemen, Schläuchen, Profilen, Dichtungen, Membranen, taktilen Sensoren für medizinische Anwendungen, taktilen Sensoren für Roboteranwendungen, Schuhsohlen und Teilen einer Schuhsohle.

The present invention also relates to a use of the rubber mixture according to the invention, preferably as described above and/or below as preferred, for producing a

• - vehicle tyre, preferably a pneumatic vehicle tyre; and/or
• - rubber article which is not a vehicle tire, particularly preferably selected from the group consisting of air springs, bellows, bands, belts, straps, hoses, profiles, seals, membranes, tactile sensors for medical applications, tactile sensors for robot applications, shoe soles and parts of a shoe sole.

The above statements regarding the compound according to the invention (including preferred embodiments) and the rubber mixture according to the invention (including preferred embodiments) apply preferably mutatis mutandis also for the use according to the invention for the production as described above. What is said below preferably also applies mutatis mutandis to the vehicle tire according to the invention.

The use for producing all tire components (including outer and/or inner components) is preferred, preferably for producing an outer component, particularly preferably for producing a horn profile, tread and/or a sidewall. The use for producing a cap of a tread having a cap/base construction is particularly preferred. Different shaping during extrusion or calendering preferably determines the type of component. Preferred inner components include a squeegee, an inner layer, a core profile, a belt, a shoulder, a belt profile, a carcass, a bead reinforcement, a bead profile and/or a bandage. Rubber mixtures for inner components are typically also referred to as body mixtures. The different components with their respective shapes and in the unvulcanized state typically serve to build a green tire. The as yet unvulcanized green tire is then preferably vulcanized.

The use according to the invention also relates to the production of rubber articles which are not vehicle tires. These rubber articles preferably have a structure made up of several layers, particularly preferably one or more than one layer comprises at least one reinforcement.

Preferred belts include rubber belts and/or conveyor belts.

Process for preparing the compound according to the invention:

• i) Herstellen oder Bereitstellen einer Verbindung gemäß Formel (B1):
  
  
• ii) Umsetzung der Verbindung gemäß Formel (B1) mit
  • - Wasserstoff und einem Keton oder Aldehyd, bevorzugt einem Keton, zu der Verbindung gemäß Formel (I):
    
  wobei
  • - R¹ ausgewählt ist aus der Gruppe bestehend aus
    • - xi) aromatischen Resten, und
    • - xii) aliphatischen C₃- bis C₁₂-Resten,
  • - R² und R³ gleich oder verschieden sind und unabhängig voneinander ausgewählt sind aus der Gruppe bestehend aus aliphatischen C₁- bis C₁₂-Resten, aromatischen Resten, Halogen-Resten, Cyano-Resten, Ester-Resten, Keton-Resten, Ether-Resten und Thioether-Resten,
  • - m 0 oder 1 oder 2 oder 3 ist,
  • - n 0 oder 1 oder 2 oder 3 oder 4 ist,
  • - X ein Ring ist, der aromatisch oder aliphatisch ist und
  • - Z ausgewählt ist aus der Gruppe bestehend aus Halogenen, Sulfonaten, Sulfonat-basierten Abgangsgruppen, Amino und Nitro, vorzugsweise aus Amino und Nitro.

The present invention also relates to a process for preparing a compound according to the invention, preferably a compound according to formula (I), comprising the process steps:

• (i) preparing or providing a compound according to formula (B1):
  
  
• ii) reacting the compound according to formula (B1) with
  • - hydrogen and a ketone or aldehyde, preferably a ketone, to give the compound according to formula (I):
    
  where
  • - R ¹ is selected from the group consisting of
    • - xi) aromatic residues, and
    • - xii) aliphatic C ₃ to C ₁₂ residues,
  • - R ² and R ³ are the same or different and are independently selected from the group consisting of aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals,
  • - m is 0 or 1 or 2 or 3,
  • - n is 0 or 1 or 2 or 3 or 4,
  • - X is a ring which is aromatic or aliphatic and
  • - Z is selected from the group consisting of halogens, sulfonates, sulfonate-based leaving groups, amino and nitro, preferably amino and nitro.

What has been said above about the compound according to the invention (preferably and in particular about compounds according to the invention which are defined above as preferred) preferably also applies mutatis mutandis to the process for preparation according to the invention. This means that for R ¹ , R ² , R ³ X, m and n all of the above statements made in connection with the description of the compound according to the invention apply, including preferred embodiments and with regard to the possibilities of any gradation in the preference and combination of these features.

Preferably, in Z the halogens comprise chlorine, bromine or iodine, preferably chlorine. Particularly preferably it does not comprise fluorine.

Preferably, in Z, the sulfonate-based leaving groups comprise triflate, nonaflate, mesylate or tosylate.

Z is very preferably nitro or amine. This means that very preferred starting compounds are corresponding amino or nitro benzimidazoles, where X is particularly preferably a phenyl ring or a cyclohexyl ring. The above statements regarding compounds of the formula (Ia), (Ib), (IIa) and (IIb) according to the invention apply accordingly with particular preference.

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein the reaction in step ii) with hydrogen is carried out by means of a catalyst, preferably by means of a hydrogenation catalyst. This means that such a catalyst is preferably used or employed in step ii). In some cases, a "hydrogenation catalyst" is also referred to as a "hydrogenation catalyst", wherein in the context of the present invention both terms have the same scope of meaning.

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein in step ii) the catalyst, preferably the hydrogenation catalyst, comprises a metal, preferably one or more than one metal selected from the group consisting of nickel, copper, iron, chromium, aluminum, palladium and platinum. Particularly preferably, the catalyst, preferably the hydrogenation catalyst, comprises a noble metal, particularly preferably palladium (Pd) and/or platinum (Pt). In other words, a noble metal catalyst is particularly preferred.

The metal, preferably the noble metal, is preferably used on carbon (C). Particularly preferred catalysts include palladium on carbon (Pd/C), platinum on carbon (Pt/C), Raney nickel and/or copper chromite, with particular preference being given to palladium on carbon (Pd/C) and/or platinum on carbon (Pt/C). It has been shown that Pt/C catalysts have the advantage of being able to convert mixtures of amino and nitrobenzimidazole equally, so that a more complete conversion is achieved. In contrast, a Pd/C catalyst is particularly suitable for converting an aminobenzimidazole, but less so for a corresponding nitrobenzimidazole.

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein the reaction in step ii) with hydrogen is carried out for a period of 1 to 30 hours, preferably 3 to 22 hours, particularly preferably 5 to 16 hours, especially preferably 8 to 13 hours.

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein the reaction with hydrogen in step ii) takes place in a pressure reactor, preferably in an autoclave.

• - mittels eines Katalysators erfolgt; und/oder (vorzugsweise und)
• - bei einer Temperatur von 40 bis 190°C erfolgt, bevorzugt von 55 bis 170°C, besonders bevorzugt von 70 bis 150°C, insbesondere bevorzugt von 85 bis 130°C; und/oder (vorzugsweise und)
• - bei einem Druck von 20 bis 70 bar erfolgt, bevorzugt von 28 bis 57 bar, besonders bevorzugt von 35 bis 45 bar.

Particularly preferred is a process according to the invention, wherein the reaction in step ii)

• - by means of a catalyst; and/or (preferably and)
• - at a temperature of 40 to 190°C, preferably from 55 to 170°C, particularly preferably from 70 to 150°C, especially preferably from 85 to 130°C; and/or (preferably and)
• - at a pressure of 20 to 70 bar, preferably 28 to 57 bar, particularly preferably 35 to 45 bar.

In the process according to the invention, the ketone in step ii) is the ketone derivative of the later radical R ¹ ; an aldehyde is accordingly the aldehyde derivative. A ketone is particularly preferred, most preferably methyl isobutyl ketone (MIBK).

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein a solvent is used in step ii), wherein preferably the solvent is identical to the ketone or aldehyde or is different from the ketone or aldehyde (preferably identical).

If the ketone or aldehyde is identical to the solvent, the solvent is also a reaction partner. This is preferably the case if the aldehyde or ketone is present in liquid form under reaction conditions. If the ketone or aldehyde is not present in liquid form under reaction conditions, the solvent is preferably inert, i.e. it is not itself a reaction partner. Preferred inert solvents include toluene, a dioxane (preferably 1,4-dioxane), 2-methyltetrahydrofuran (2-MTHF) and/or xylene. This is preferably the case if the aldehyde or ketone is present in solid form under reaction conditions. In the latter case, the ketone or aldehyde is preferably used as a reactant only in stoichiometrically required amounts (in some cases preferably in a slight excess).

Particularly preferred is a process according to the invention, preferably as described above and/or below as preferred, wherein the ketone or the aldehyde, particularly preferably the ketone, is present in liquid form in step ii), particularly preferably as solvent and reaction partner. This means that an additional compound such as toluene or xylene can be dispensed with.

Preference is given to a process according to the invention, preferably as described above and/or below as preferred, wherein after step ii) one or more than one purification takes place, preferably filtration, chromatography, recrystallization and/or washing with a solvent. A preferred solvent, which is preferably different from the solvent used in step ii), comprises an alcohol and/or 2-MTHF, preferably methanol and/or ethanol, particularly preferably ethanol. Preference is given to chromatography comprising silica gel. Preference is given to recrystallization from hydrocarbons, preferably from C5 to C20 aliphatic compounds, particularly preferably from cyclohexane and/or cycloheptane.

The invention is explained in more detail below by means of embodiments.

Synthesis of a compound according to formula (I):

1. 1. Stufe (Synthese von 2-Phenyl-1 H-benzo[d]imidazol-6-amin):
   • 2-Phenyl-1 H-benzo[d]imidazol-6-amin wurde gemäß C. Diaz, J. Comput. Aided Mol Des., 2015, 29, 143-154 dargestellt. Es wurde ein Gemisch enthaltend das Amin (80%) und die korrespondierende Nitroverbindung (20%) erhalten.
2. 2. Stufe (N-(1,3-Dimethylbutylamino)-2-phenyl-1 H-benzo[d]imidazol-6-amin):

The compound according to formula (III), as an exemplary embodiment of a compound according to formula (I), was prepared in several steps in the following concrete manner:

1. 1st step (synthesis of 2-phenyl-1 H-benzo[d]imidazol-6-amine):
   • 2-Phenyl-1 H-benzo[d]imidazol-6-amine was prepared according to C. Diaz, J. Comput. Aided Mol Des., 2015, 29, 143-154 A mixture containing the amine (80%) and the corresponding nitro compound (20%) was obtained.
2. 2nd stage (N-(1,3-dimethylbutylamino)-2-phenyl-1H-benzo[d]imidazole-6-amine):

The mixture obtained in the first stage was reacted in the second stage using a platinum on carbon (Pt/C) catalyst according to the following scheme.

0.80 g (3.82 mmol, 0.8 eq) of 2-phenyl-1H-benzo[d]imidazol-6-amine, 0.20 g (0.84 mmol, 0.2 eq) of 6-nitro-2-phenyl-1H-benzo[d]imidazole, 0.40 g of platinum on carbon (5%; 0.4 g on 4.67 mmol of substrate) and 20.0 mL of methyl isobutyl ketone (MIbK) were weighed into a stainless steel autoclave equipped with a Teflon liner. 40 bar of hydrogen were then applied and the reaction mixture was stirred at 120°C for 10 hours. After the reaction had ended, the excess hydrogen was drained off. A suspension was obtained as the reaction product, which was filtered through Celite and then washed with ethanol. The resulting filtrate was concentrated to dryness and then further dried in vacuo. The resulting dried product was purified by column chromatography (dichloromethane/methanol; 100:0 => 95:5). A reddish-brown solid was obtained as the purified product; yield 0.31 g (23% of theory).

¹ H-NMR (500 MHz, DMSO-d6) δ = 12.28 (s, 1H), 8.06 (d, J = 7.8 Hz, 2H), 7.49 (t, J = 7.6 Hz, 2H), 7.40 (t, J = 7.5 Hz, 1H), 7.35 - 7.30 (m, 1H), 6.56 (d, J = 10.4 Hz, 2H), 4.36 (t, 1H), 3.45 (dt, J = 6.8, 4.1 Hz, 1H), 1.78 (dh, J = 13.5, 6.8 Hz, 1H), 1.50 (dt , J = 13.8, 7.0 Hz, 1H), 1.23 (dt, J = 13.7, 6.9 Hz, 1H), 1.13 (d, J = 6.2 Hz, 3H), 0.95 (d, J = 6.6 Hz, 3H), 0.89 (d, J = 6.6 Hz, 3H).

¹³ C-NMR (126 MHz, DMSO-d6) δ = 148.5, 145.7, 137.0, 136.2, 131.3, 129.2, 129.1, 126.0, 119.6, 111.5, 92.0, 46.5, 46.4, 25.1, 23.3, 23.0, 21.1, 19.0.

Mass spectrometry result: ESI-MS [M+H] ⁺ = 294

measurement of the oxidation induction time (OIT)

The compound according to formula (III) was investigated for its potential protective effect as an anti-aging agent or antioxidant by measuring the oxidation induction time under laboratory conditions.

For this purpose, the compound according to formula (III) and comparatively 6PPD were each mixed with a polymer (liquid synthetic polyisoprene (IR),

LIR-50, Kuraray, weight average molecular weight distribution M _w = 54,000 g/mol, glass transition temperature T _g = -63°C) was heated at 180°C until oxidation began. The time required for this is the above-mentioned "oxidation induction time" in the sense of the present invention.

• Starttemperatur 35°C, zunächst Aufheizen auf 170°C mit einer Heizrate von 20 K/min (Kelvin pro Minute), dann weiteres Aufheizen auf 180°C mit einer Heizrate von 1 K/min; Spülgas: Stickstoff (N₂) mit einem Volumenstrom von 50 mL/min).

Preheat to 180°C:

• Starting temperature 35°C, first heating to 170°C with a heating rate of 20 K/min (Kelvin per minute), then further heating to 180°C with a heating rate of 1 K/min; purge gas: nitrogen (N ₂ ) with a volume flow of 50 mL/min).

The sample was kept isothermally under N ₂ atmosphere at 180°C for 5 minutes and then switched to O ₂ atmosphere (with a flow rate of 50 mL/min).

The oxidation was observed using DSC (differential scanning calorimetry). The time in minutes until oxidation occurred was measured. The results are summarized in Table 1 in comparison with the known anti-aging agent 6PPD. Table 1, oxidation induction time in [min] Connection time [min] 6PPD 116 formula (III) 232

Table 1 shows that the compound according to formula (III) achieves a significantly improved protective effect compared to 6PPD at the temperature of 180°C, which is considered to be particularly demanding, since it takes surprisingly longer until oxidation is detectable. The improvement observed here experimentally is about 100%.

The compounds of formula (I) in general and formula (III) in particular are based on a benzimidazole basic structure, in particular a 2-phenylbenzimidazole basic structure. In comparison, 6PPD is based on a diphenylamine basic structure. Benzimidazole or phenylbenzimidazole is significantly less harmful to the environment and health.

Thus, the compound according to formula (III) according to the invention, as a representative of the compound according to formula (I), is not only more environmentally and health-friendly than 6PPD or other representatives of this known class of compounds. In addition, the compound or class of compounds according to the invention achieves an outstandingly better protective effect.

The compound according to the invention according to formula (III) as a representative of the compound according to the invention according to formula (I) has sufficient solubility in rubber mixtures.

In a complementary experiment, the solubility was further improved by having the phenyl ring bear an alkyl substituent or by having the phenyl ring fully hydrogenated (data not shown).

For the (here particularly preferred) application in a rubber mixture for vehicle tires, the compound according to the invention according to formula (I), represented by a compound according to formula (III), is added, for example, instead of the anti-aging agents known in the prior art, such as 6PPD, 7PPD or IPPD, etc., in a manner known to the person skilled in the art in one of the mixing stages in the preparation of the rubber mixture.

For this purpose, the compound according to formula (III) is mixed in, for example, in various amounts (see Table 2). The resulting examples according to the invention are marked with E1 and E2.

For comparison, rubber mixtures containing 6PPD instead of the compound according to formula (III) as an anti-aging agent with otherwise identical composition are used, whereby an equal molar exchange was carried out between V1 and E1 and between V2 and E2. The amounts in Table 2 are given in the unit phr. The reference (Ref.) is without anti-aging agent.

For all mixtures, the sum of the amounts of anti-aging agent (6PPD or compound according to formula (III)) and plasticizer oil MES is 10 phr. Table 2, exemplary rubber mixtures [phr] ingredient V1 E1 V2 E2 Ref. NR 100 100 100 100 100 Ruß N 339 50 50 50 50 50 MES 8.0 7.7 5.0 4.2 10 6PPD 2.0 - 5.0 - - compound formula (III) - 2.3 - 5.8 - ZnO 3 3 3 3 3 stearic acid 2 2 2 2 2 TBBS 1.2 1.2 1.2 1.2 1.2 sulfur 1.2 1.2 1.2 1.2 1.2

The examples of rubber mixtures according to the invention also show an anti-aging effect that is at least equivalent or even improved compared to typical rubber mixtures known in particular from the prior art (data not shown). The reference, on the other hand, shows an overall insufficient anti-aging effect.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• US 5,140,055 A [0007]
• WO 99/09036 A1 [0108]
• WO 2008/083241 A1 [0110]
• WO 2008/083242 A1 [0110]
• WO 2008/083243 A1 [0110]
• WO 2008/083244 A1 [0110]

Cited non-patent literature

• C. Diaz, J. Comput. Aided Mol Des., 2015, 29, 143-154 [0156]

Claims (15)

Compound according to formula (I):

where - R ¹ is selected from the group consisting of - xi) aromatic radicals, and - xii) aliphatic C ₃ to C ₁₂ radicals, - R ² and R ³ are the same or different and are independently selected from the group consisting of aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals, - m is 0 or 1 or 2 or 3, - n is 0 or 1 or 2 or 3 or 4, and - X is a ring which is aromatic or aliphatic. connection to claim 1 , where X comprises 6 carbon atoms, preferably a phenyl radical or a cyclohexyl radical. connection to claim 1 or 2 , having a structure according to formula (la) or (Ib)

where R ¹ , R ² , R ³ , m and n as in claim 1 are defined. Connection to one of the Claims 1 until 3 , having a structure according to formula (IIa) or (IIb)

where R ¹ , R ² , R ³ , m and n as in claim 1 are defined. Connection to one of the Claims 1 until 4 , where n and m are different or identical. connection to claim 4 or 5 , where in formula (Ia) and/or (IIa) m is zero and n is 1, and preferably R ³ is an aliphatic C ₁ to C ₁₂ radical. connection to claim 4 or 5 , where in formula (Ib) and/or (IIb) m and n are zero. Connection to one of the Claims 1 until 7 , where R ¹ is 1,3-dimethylbutyl, phenyl, benzyl or cyclohexyl, preferably 1,3-dimethylbutyl. Connection to one of the Claims 1 until 8 , having the structure according to formula (III):

Rubber mixture containing the compound according to one of the Claims 1 until 9 , preferably comprising one or more than one diene rubber. Vehicle tyre, preferably a pneumatic vehicle tyre, which contains the rubber mixture according to claim 10 in at least one component, preferably in at least one outer component, wherein the outer component is preferably a tread, a sidewall and/or a horn profile. Using the connection according to one of the Claims 1 until 9 as an ageing inhibitor and/or antioxidant, preferably in - vehicle tires, particularly preferably pneumatic vehicle tires; - rubber articles which are not vehicle tires, particularly preferably selected from the group consisting of air springs, bellows, bands, belts, straps, hoses, profiles, seals, membranes, tactile sensors for medical applications, tactile sensors for robot applications, shoe soles and parts of a shoe sole; - oils and/or greases; and/or - fuels and/or lubricants. Use of the rubber compound according to claim 10 for producing a - vehicle tire, preferably a pneumatic vehicle tire; and/or - rubber article which is not a vehicle tire, particularly preferably selected from the group consisting of air springs, bellows, bands, belts, straps, hoses, profiles, seals, membranes, tactile sensors for medical applications, tactile sensors for robot applications, shoe soles and parts of a shoe sole. A process for preparing a compound according to formula (I), comprising the process steps: i) preparing or providing a compound according to formula (B1):

ii) reacting the compound according to formula (B1) with - hydrogen and a ketone or aldehyde, preferably a ketone, to give the compound according to formula (I):

where - R ¹ is selected from the group consisting of - xi) aromatic radicals, and - xii) aliphatic C ₃ to C ₁₂ radicals, - R ² and R ³ are the same or different and are independently selected from the group consisting of aliphatic C ₁ to C ₁₂ radicals, aromatic radicals, halogen radicals, cyano radicals, ester radicals, ketone radicals, ether radicals and thioether radicals, - m is 0 or 1 or 2 or 3, - n is 0 or 1 or 2 or 3 or 4, - X is a ring which is aromatic or aliphatic and - Z is selected from the group consisting of halogens, sulfonates, sulfonate-based leaving groups, amino and nitro, preferably amino and nitro. procedure according to claim 14 , wherein the reaction in step ii) - is carried out by means of a catalyst; and/or - at a temperature of 40 to 190°C, preferably from 55 to 170°C, particularly preferably from 70 to 150°C, especially preferably from 85 to 130°C; and/or - at a pressure of 20 to 70 bar, preferably from 28 to 57 bar, particularly preferably from 35 to 45 bar.