DE-102024210765-A1 - Vehicle tires, vulcanizate and sulfur-crosslinkable rubber compound with protection against aging phenomena

Abstract

The invention relates to a rubber compound containing at least the following components, as well as its vulcanizate and its use in vehicle tires: a) 10 to 20 phr of polyisoprene selected from natural and synthetic polyisoprene, b) 80 to 90 phr of at least one diene rubber selected from butadiene rubber and styrene-butadiene rubber, wherein 60 to 70 phr of the diene rubber is partially hydrogenated, wherein the degree of hydrogenation, i.e., the proportion of the original double bonds of the partially hydrogenated diene rubber that have been fully hydrogenated, is 50 to 90%.

Inventors

• Armand Gabriel Becheanu-Böke
• Christoph Vatterott
• Catarina Sà
• Arne Visscher
• Kathrin Wehming-Bomkamp

Assignees

• CONTINENTAL REIFEN DEUTSCHLAND GMBH

Dates

Publication Date

20260513

Application Date

20241108

Claims (12)

1. A rubber compound containing at least the following components: a) 10 to 20 phr of polyisoprene selected from natural and synthetic polyisoprene, b) 80 to 90 phr of at least one diene rubber selected from butadiene rubber and styrene-butadiene rubber, preferably solution-polymerized SBR, where 60 to 70 phr of the diene rubber is partially hydrogenated, where the degree of hydrogenation, i.e., the proportion of the original double bonds of the partially hydrogenated diene rubber that have been fully hydrogenated, is 50 to 90%.
2. rubber compound according to Claim 1 , wherein the proportion of the diene rubbers butadiene rubber and styrene-butadiene rubber in the rubber mixture is preferably 85 phr.
3. Rubber compound according to one of the Claims 1 or 2 , wherein the proportion of SBR in the rubber mixture is above 60 phr, preferably 65 phr.
4. Rubber compound according to one of the Claims 1 until 3 , wherein the rubber mixture contains SBR, wherein the SBR contained is partially hydrogenated.
5. rubber compound according to Claim 4 , where only the diene rubber SBR is partially hydrogenated.
6. Rubber compound according to one of the Claims 1 until 5 , wherein the degree of hydrogenation is 70% to 80%, preferably between 75% and 80%.
7. Rubber compound according to one of the Claims 1 until 6 , wherein the rubber mixture comprises at least 100 phr, preferably at least 110 phr, more preferably at least 120 phr fillers.
8. Rubber compound according to one of the Claims 1 until 7 , wherein the rubber mixture comprises a maximum of 3 phr, preferably not more than 2.5 phr, particularly preferably not more than 2.2 phr of anti-aging agents.
9. Rubber compound according to one of the Claims 1 until 8 , whereby the rubber compound continues to include at least plasticizers, sulfur, vulcanizing chemicals and optionally other additives.
10. Vulcanizate obtained by sulfur vulcanization of a rubber mixture according to one of the Claims 1 until 9 .
11. Use of the vulcanizate according to Claim 10 in a vehicle tire.
12. Vehicle tire, which is a new tire, a hot retreaded tire or a cold retreaded tire, which is a pneumatic tire, a solid rubber tire or a non-pneumatic tire with spoke construction, wherein the tire contains in at least one component the vulcanizate according to Claim 10 contains.

Description

The invention relates to a vehicle tire. Furthermore, the invention relates to a vulcanizate, in particular for use in vehicle tires or components of the vehicle tire, and to a rubber composition or a sulfur-curable rubber mixture from which the vulcanizate can be formed. The rubber composition largely determines the properties of a vehicle tire. Therefore, these rubber compounds are subject to high demands. In particular, the aging behavior plays a crucial role. Aging here refers specifically, but not exclusively, to the changes in the rubber material due to interactions with oxygen and especially ozone in the atmosphere. Aging leads, in particular, to an increasing porosity or stiffening of the rubber material. In the current state of the art, there are basically two ways to protect a rubber compound from aging: the use of aging inhibitors in the rubber compound (see, for example, K. Berghus et al.: Handbook for the Rubber Industry, 2nd edition, Chapter 4) or the coating of the surface of the formed vulcanizate, for example with a polymer with saturated carbon chains, such as from the EP 0 228 982 A2 known. Both of the above-mentioned options have disadvantages. For example, the antioxidants used in current technology are inherently toxic. The necessary addition of antioxidants for antioxidant protection leads to significant environmental pollution. Therefore, legal limits regarding the use of known antioxidants such as 6PPD (N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine) or DTPD (N,N'-Di-(p-tolyl)-p-phenylenediamine, N,N'-(p-Phenylene)-ditoluidine) or other phenylenediamines (PD) are already under discussion. Applying additional coatings, in turn, involves difficulties and increased effort and costs in the processing and manufacturing of the tires. Furthermore, the protective effect of coatings is limited once abrasion occurs. It is therefore at least one object of the present invention to reduce the dosage of anti-aging agents, while maintaining the properties of the tires in their new and used condition, in particular their resistance to aging. With the rubber compound, the vulcanizate and the vehicle tire according to the invention, the properties of the tire can be maintained and the proportion of toxic aging agents can be reduced. The invention encompasses all advantageous embodiments, which are reflected, inter alia, in the claims. In particular, the invention also encompasses embodiments resulting from the combination of different features, for example, components of the rubber compound or elements of the tire, with varying degrees of preference given to these features, such that a combination of a first feature designated as "preferred" or described within the framework of an advantageous embodiment with a further feature designated, for example, as "particularly preferred," is also encompassed by the invention. The following section describes in more detail the components of the rubber compound according to the invention and the properties of the vulcanizate and tire produced therefrom. All information relating to the components of the rubber compound according to the invention, regardless of the grade, when these features are preferred, also applies accordingly to the vulcanizate according to the invention, the vehicle tire according to the invention, and uses according to the invention. The unit phr (parts per hundred parts of rubber by weight) used in this document is the standard unit of measurement for compound formulations in the rubber industry. The dosage of the parts by weight of the individual substances is based on 100 parts by weight of the total mass of all rubbers present in the mixture with a molecular weight Mw according to GPC greater than 20,000 g/mol. The specified value ranges always include the limit values. According to the invention, the rubber mixture contains at least polyisoprene (isoprene rubber, IR/NR) and at least one diene rubber selected from one or more of a butadiene rubber (synonyms: BR, BR rubber, polybutadiene) and styrene-butadiene rubber (SBR). According to the invention, the isoprene rubber can preferably be natural polyisoprene (NR) or may also contain synthetic polyisoprene (IR) or both. The proportion of polyisoprene in the rubber mixture is a maximum of 30 phr and preferably a minimum of 5 phr, more preferably between 10 and 20 phr, more preferably between 12 phr and 18 phr, and particularly preferably 15 phr. Diene rubbers are 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. According to the invention, the proportion of diene rubbers BR and/or SBR in the rubber mixture is at least 70 phr and at most 95 phr. Preferably, the proportion of diene rubbers BR and/or SBR in the rubber mixture is at least 80 phr and at most 90 phr, more preferably between 82 phr and 88 phr, particularly preferably 85 phr. Preferably, the rubber mixture