Vulcanizable rubber mixtures, vulcanized materials, and rubber products

Abstract

The present invention relates to a vulcanizable rubber mixture containing: a) an LTG diene rubber selected from the group consisting of butadiene rubber and styrene-butadiene rubber, having a glass transition temperature Tg in the range of -120°C to -30°C as measured using DSC; b) silicic acid; c) a specific polyetheramine in a total mass proportion in the range of 0.1 to 10 phr; and d) a diene rubber different from the LTG diene rubber.

Description

[Technical Field]

[0001] The present invention relates to vulcanizable rubber compounds, vulcanizates producible therefrom, and rubber articles, particularly pneumatic vehicle tires, containing the vulcanizates. [Background technology]

[0002] While the automotive industry has been shaped by numerous technological innovations, it is also one of the sectors that has faced fundamental challenges since the beginning of the 21st century. Rising customer awareness of environmental issues such as emission profiles and resource efficiency is calling for new concepts in mobility. At the same time, demands for improved vehicle functionality and requirements regarding driving safety are increasing. Meeting these challenges is not just the job of actual car manufacturers. In fact, many of these challenges are heavily influenced by the properties of vehicle tires, so optimizing tire properties is a key area of ​​innovation.

[0003] The key factors for optimizing the properties of vehicle tires and other rubber products, such as belts, drive belts, and hoses, are the vulcanizable rubber compounds used in their manufacture and the rubber stock obtained by vulcanization. Many relevant properties of pneumatic vehicle tires, such as wet grip, rolling resistance, and wear behavior, are closely related to the composition of the rubber stock, for example, of the tread. Therefore, the focus of much research effort is on optimizing the properties of the rubber compositions used, which usually imposes very high requirements. At the same time, conflicting objectives exist with regard to many properties of vehicle tires. This means that these properties cannot be optimized independently of each other, and improving one parameter may worsen another.

[0004] In recent decades, great advances have been made in the field of composition development, where a key innovation has been the at least partial replacement of, for example, carbon black-based fillers with silicon-containing compounds, in particular silicon dioxide compounds such as fumed silica and precipitated silica.

[0005] EP 2725059 A1 discloses that the combination of polyetheramines with silica results in advantageous rubber compounds with improved levels of performance, particularly with respect to wear behavior and the conflicting objectives between rolling resistance and wet grip. Furthermore, it has been found that the corresponding rubber compounds have improved processing properties. Additional information on the technical background of polyetheramines is disclosed, for example, in WO 2013 / 092526 A1, U.S. Patent Application Publication No. 2008 / 033082 A1, and WO 2016 / 030469 A1. Summary of the Invention [Problem to be solved by the invention]

[0006] Although the vulcanizable rubber compounds known from the prior art are capable of achieving generally advantageous results in many respects, it is believed that the corresponding compositions and the vulcanizates producible therefrom are often still in need of improvement with regard to application-related properties, in particular in order to meet the requirements of modern pneumatic vehicle tires for high-performance applications.

[0007] The main object of the present invention was to overcome or at least mitigate the drawbacks of the prior art and to provide an advantageous vulcanizable rubber compound having an advantageous property profile and corresponding vulcanizates producible therefrom.

[0008] In particular, it is an object of the present invention to provide vulcanizable rubber compounds that have excellent processing properties, which desirably can reduce the need for compounds that are potentially harmful to health and / or the environment, particularly guanidine-based accelerators.

[0009] It was a further object of the present invention to provide vulcanizable rubber compounds and corresponding vulcanizates producible therefrom which have excellent rolling properties, in particular advantageous rolling resistance, good braking properties and advantageous handling properties.

[0010] Furthermore, it was an object of the present invention to provide vulcanizable rubber compounds and corresponding vulcanizates producible therefrom which have excellent mechanical properties, in particular with regard to stiffness and improved wear properties.

[0011] In particular, the object of the present invention was to optimally resolve the existing objective conflict between processing properties, mechanical properties and rolling properties.

[0012] In this context, a further object of the present invention was to ensure that the vulcanizable rubber compounds and vulcanizates provided can be produced as far as possible using manufacturing processes and materials already in use today in the field of rubber processing.

[0013] A further object of the present invention was to provide corresponding rubber articles comprising the vulcanizates provided, in particular pneumatic vehicle tires, having advantageous properties.

[0014] The inventors of the present invention have now surprisingly found that the above object can be achieved when the vulcanizable rubber compound contains not only a diene rubber and silica, but also specific parts by weight of specific polyetheramines and low glass transition temperature butadiene rubber or styrene-butadiene rubber as defined in the claims. [Means for solving the problem]

[0015] The above-mentioned object is therefore achieved by the subject matter of the invention as defined in the claims. Preferred embodiments according to the invention will become apparent from the dependent claims and the following description. DETAILED DESCRIPTION OF THE INVENTION

[0016] In particularly preferred embodiments, the embodiments referred to below as preferred are combined with features of other embodiments referred to as preferred. Thus, combinations of two or more of the embodiments referred to below as particularly preferred are most highly preferred. Similarly, preferred are embodiments in which features of one embodiment referred to as somewhat preferred are combined with one or more additional features of other embodiments referred to as somewhat preferred. Preferred vulcanizate, rubber article, and use features will be apparent from the features of the preferred vulcanizable rubber compounds.

[0017] When the following text discloses, for a compound component, such as a diene rubber or polyetheramine, not only a specific amount / part of said compound component but also a preferred embodiment of the compound component, the text also specifically discloses the specific amount / part of the compound component of the preferred embodiment. Furthermore, for the corresponding specific total amount / part of the compound component, it is disclosed that at least a portion of the compound component may be of the preferred embodiment, and it is also specifically disclosed that the compound component of the preferred embodiment may be present in a specific amount / part within the specified total amount or total part range.

[0018] The present invention provides a vulcanizable rubber compound comprising: a) one or more LTG diene rubbers selected from the group consisting of butadiene rubber and styrene-butadiene rubber having a glass transition temperature Tg in the range of -120°C to -30°C as measured by DSC; b) one or more fillers selected from the group consisting of silica; c) one or more polyetheramines in a total weight range of 0.1 to 10 phr, Formula I): I)R 1 R 2 N-(R 5 ) m -XR 6 -NR 3 R 4 and wherein in formula I) R 1 , R 2 , R 3 , and R 4 are each independently hydrogen or a branched or unbranched hydrocarbon radical having 1 to 10 carbon atoms, m is 0 or 1, and R 5 and R 6 are each independently a branched or unbranched hydrocarbon chain having 1 to 10 carbon atoms; X is a group represented by formula II): II)-(CHR 7i -CHR 8i -O) x - In formula II), x is in the range of 2 to 30, and R 7i and R 8i is in each occurrence independently and independently of the other monomer units in the polyether chain, hydrogen or a hydrocarbon radical having 1 or 2 carbon atoms; d) one or more diene rubbers different from LTG diene rubber; The present invention relates to a vulcanizable rubber compound containing

[0019] The vulcanizable rubber compound itself and its typical components, as well as the conventional manufacturing process for obtaining the corresponding vulcanizable rubber compound by mixing the components in particular, are well known to those skilled in the art of rubber processing.

[0020] According to standard practice, the above-defined components of a vulcanizable rubber compound are each referred to as "one or more." As is customary in the industry, the term "one or more" refers to the chemical nature of the corresponding compound, not its molar amount. For example, a vulcanizable rubber compound may contain only SBR as the diene rubber, which means that the vulcanizable rubber compound contains multiple corresponding molecules.

[0021] When parts by weight are given in the text below, they are often given as the total parts by weight of one or more components as is customary in the industry, thereby indicating that the combined parts by weight of the correspondingly formed components meet the corresponding criteria.

[0022] The unit phr (parts by weight per 100 parts by weight of rubber) used herein is a conventional indication of the amount of compound in the rubber industry and represents the weight parts of components in a rubber compound based on the weight of high molecular weight rubber (having a weight-average molar mass Mw greater than 60,000 g / mol as measured by GPC) present in the rubber compound, with the total weight parts of the high molecular weight rubber in the rubber compound corresponding to 100 phr. The unit phf (parts by weight per 100 parts by weight of filler) is also a conventional indication of the amount in the rubber industry of compound compounds, particularly filler coupling agents, and is based on the weight of the filler present in the rubber compound. In the context of the present invention, the unit phf is based only on the silica present in the vulcanizable rubber compound, the total weight parts of which correspond to 100 phf. In other words, other fillers, such as carbon black, which may be present, are not included in the phf calculation.

[0023] The vulcanizable rubber compound according to the present invention contains at least one diene rubber. As understood by those skilled in the art, diene rubber refers to a rubber obtained by (co)polymerization of dienes and / or cycloalkenes, resulting in a C=C double bond in the main chain or in a side group. The advantage of the vulcanizable rubber compound according to the present invention is its high flexibility in the diene rubber used, so that, in principle, any diene rubber commonly used in the industry can be considered to be usable, except for the LTG diene rubber, which will be further characterized below. Therefore, those skilled in the art will understand that at least one additional type of diene rubber, other than butadiene rubber or styrene-butadiene rubber, having a glass transition temperature Tg in the range of −120°C to −30°C, as measured by DSC, is always used in combination with the LTG diene rubber. In this regard, however, the inventors prefer vulcanizable rubber compounds according to the invention, in which the one or more diene rubbers are selected from the group consisting of natural polyisoprene, synthetic polyisoprene, epoxidized polyisoprene, butadiene rubber, solution-polymerized styrene-butadiene rubber, emulsion-polymerized styrene-butadiene rubber, polynorbornene, ethylene-propylene-diene rubber, nitrile rubber, acrylate rubber, styrene-isoprene-butadiene terpolymer, butyl rubber, and halobutyl rubber, and the one or more diene rubbers are preferably 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), and the one or more diene rubbers are particularly preferably selected from the group consisting of solution-polymerized styrene-butadiene rubber and emulsion-polymerized styrene-butadiene rubber. In this regard, preference is also given to vulcanizable rubber compounds according to the invention, in which, additionally or alternatively, at least one diene rubber, preferably all of the one or more diene rubbers, are end-group-modified and / or chain-modified diene rubbers, preferably end-group-modified diene rubbers.The modification may be one or more functional groups selected from the group consisting of hydroxyl groups, ethoxy groups, epoxy groups, siloxane groups, amino groups, aminosiloxane groups, carboxyl groups, phthalocyanine groups, and silane-sulfide groups.

[0024] In particular, SBR, BR, and IR / NR have been found to be suitable diene rubbers for obtaining vulcanizable rubber compounds which can be converted by vulcanization into particularly effective vulcanizates.

[0025] Therefore, first preference is given to a vulcanizable rubber compound according to the invention which, in addition to the LTG diene rubber, comprises as diene rubber preferably parts by weight of styrene-butadiene rubber, preferably solution-polymerized styrene-butadiene rubber, in the range of 50 to 98 phr, particularly preferably in the range of 55 to 96 phr, most particularly preferably in the range of 60 to 90 phr.

[0026] Additionally or alternatively, preferred is a vulcanizable rubber compound according to the invention which comprises, in addition to the LTG diene rubber, as diene rubber, preferably 1 to 35 phr, particularly preferably 2 to 30 phr, and most particularly preferably 5 to 25 phr of butadiene rubber. The butadiene rubber used in addition to the LTG diene rubber may be, for example, a so-called high-cis-butadiene rubber or a low-cis-butadiene rubber, where high-cis-butadiene rubber refers to a polybutadiene having a cis content of 90% or more by mass.

[0027] Additionally or alternatively, preferred vulcanizable rubber compounds according to the present invention contain natural and / or synthetic polyisoprene, preferably natural polyisoprene, in a total weight ratio of 1 to 30 phr, particularly preferably 2 to 20 phr, and most particularly preferably 5 to 15 phr, as diene rubber. However, particularly for truck tire applications, weight ratios of 60 to 100 phr, preferably 60 to 80 phr, are also contemplated. The natural and / or synthetic polyisoprene may be cis-1,4-polyisoprene or 3,4-polyisoprene. However, it is preferred to use cis-1,4-polyisoprene, particularly one with a cis-1,4 content of 90% or more by mass.

[0028] It has been found to be advantageous to mix two or more diene rubbers in order to optimally adapt the physicochemical / mechanical properties of the vulcanizates that can be produced to the requirements of a particular application.Therefore, preferred vulcanizable rubber compounds according to the invention comprise two or more, preferably three or more different diene rubbers as diene rubbers, particularly preferably SBR and NR and / or BR, and most preferably SBR, NR and BR.

[0029] Additionally or alternatively, preference is given to vulcanizable rubber compounds according to the invention in which the diene rubber has a weight-average molar mass Mw, determined by GPC, in the range of 150,000 to 5,000,000 g / mol, preferably in the range of 250,000 to 2,500,000, particularly preferably in the range of 300,000 to 1,500,000. In the context of the present invention, the determination of the number-average molar mass or weight-average molar mass or centrifuge-average molar mass is carried out by gel permeation chromatography in accordance with DIN 55672-1:2016-03 (GPC with tetrahydrofuran as eluent, polystyrene standards; size exclusion chromatography).

[0030] The vulcanizable rubber compound according to the present invention comprises one or more fillers selected from the group consisting of silica. In the context of the present invention, the German original text of this application uses the German term "Kieselsaeure" (silicic acid), which is commonly used in the industry, and related compounds are sometimes called "Silika" based on the English term "silica." For those skilled in the rubber processing industry, this traditional German term refers to amorphous, i.e., non-crystalline, silicon dioxide, particularly so-called fumed silica and precipitated silica. In other words, the vulcanizable rubber compound according to the present invention is a rubber compound comprising one or more fillers selected from the group consisting of fumed silica and precipitated silica, particularly preferably precipitated silica.

[0031] Basically, one or more fillers are used in a volume of 35 to 400 m 2 / g, preferably 35 to 350 m 2 / g, particularly preferably 85 to 320 m 2 Preference is given to vulcanizable rubber compounds according to the invention having a nitrogen surface area (BET surface area) according to DIN ISO 9277:2014-01 in the range of 30 to 400 m / g, most particularly preferably in the range of 120 to 235 m / g. Additionally or alternatively, one or more fillers may be present in an amount of 30 to 400 m / g. 2 / g, preferably 330 to 330m 2 / g, particularly preferably 80 to 300m 2 / g, most particularly preferably 115 to 200m 2 Preferably, vulcanizable rubber compounds according to the present invention have a CTAB surface area according to ASTM D3765-03 in the range of 1000 / g.

[0032] With regard to the amount of filler that can be used, the inventors have found that the vulcanizable rubber compounds according to the invention advantageously show excellent results even at high filler contents. However, the inventors believe that the solutions specified in the context of the invention are most advantageous, especially at moderate filler contents. Therefore, vulcanizable rubber compounds according to the invention are preferred which contain one or more fillers in a total amount of parts by weight ranging from 5 to 250 phr, preferably from 20 to 180 phr, particularly preferably from 30 to 140 phr, and most particularly preferably from 40 to 110 phr.

[0033] In addition to the silica used according to the present invention, additional fillers may also be present, thereby making it possible to specifically adjust the properties of the vulcanizable rubber compound. Vulcanizable rubber compounds according to the present invention are preferred, comprising one or more additional fillers selected from the group consisting of carbon black, aluminum hydroxide, titanium dioxide, magnesium oxide, and phyllosilicates, with the total weight of the additional fillers preferably ranging from 0.1 to 100 phr, particularly preferably from 0.5 to 50 phr. The carbon black used preferably has an iodine adsorption capacity according to ASTM D1510 of 30 to 250 g / kg, preferably 30 to 180 g / kg, particularly preferably 40 to 130 g / kg, and a DBP value according to ASTM D2414 of 30 to 200 ml / 100 g, preferably 70 to 200 ml / 100 g, particularly preferably 90 to 200 ml / 100 g.

[0034] The vulcanizable rubber compound according to the present invention contains at least one polyetheramine having a specific structure. Polyetheramines are well known to those skilled in the art. These are polyetherpolyols in which the terminal hydroxyl groups have been converted to amino groups by an amination reaction to produce polyamines. When linear, i.e., unbranched, polyetherdiols are aminated, the polyetheramines are diamines of polyalkylene glycols. The base polyetherdiol is preferably prepared from an alkylene oxide, such as butylene oxide, ethylene oxide, or propylene oxide. Polyetheramines are commercially available, particularly from Huntsman, under the trade names Jeffamine D-230, ED-600, ED-900, or EDR-148.

[0035] The polyetheramines used according to the invention are selected from the group consisting of polyetheramines of formula I): I)R 1 R 2 N-(R 5 ) m -XR 6 -NR 3 R 4 (In the formula, R 1 , R 2 , R 3 , and R 4 are each independently hydrogen or a branched or unbranched hydrocarbon radical having 1 to 10 carbon atoms, m is 0 or 1, and R 5 and R 6 are each independently a branched or unbranched hydrocarbon chain having 1 to 10 carbon atoms; X is a member of formula II): II)-(CHR 7i -CHR 8i -O) x - In formula II), x is in the range of 2 to 30, and R 7i and R 8iis in each occurrence, independently and independently of the other monomer units in the polyether chain, hydrogen or a hydrocarbon group having 1 or 2 carbon atoms).

[0036] R 1 , R 2 , R 3 , and R 4 The organic radicals in the formula (I) define the radicals of the amino groups of the diamine and are generated from the materials used in the amination reaction. As understood by those skilled in the art, these radicals are in principle independent of each other. This is true for example for R 2 Even if R is a hydrocarbon radical 1 means that R may be hydrogen. 1 , R 2 , R 3 , and R 4 are each independently hydrogen or a branched or unbranched, preferably unbranched, hydrocarbon radical having 1 to 5 carbon atoms, preferably 2 to 5 carbon atoms. 1 and R 2 At least one of the radicals and / or R 3 and R 4 Particularly preferred are vulcanizable rubber compounds according to the invention, in which at least one of the radicals is hydrogen. 1 Radicals and R 3 Radicals and / or R 2 Radicals and R 4 Most particularly preferred are vulcanizable rubber compounds according to the invention in which the radicals are identical. 1 , R 2 , R 3 , and R 4 Particular preference is given to vulcanizable rubber compounds according to the invention in which the radical is hydrogen.

[0037] One of the amino groups may be bonded directly to the polyether chain X (m=0) or through a hydrocarbon chain (m=1). In preferred polyetheramines, which are prepared from alkylene oxides, one of the amino groups is bonded directly to the polyether chain X (m=0) and the other amino group is bonded through a hydrocarbon chain R 6 The hydrocarbon chains are linked together, and this hydrocarbon chain ultimately becomes essentially the last building block of the polyether chain. However, this last building block no longer contains an oxygen atom as a result of the amination, and is therefore no longer considered part of the polyether chain X. Therefore, R 5 and R 6 are each independently a branched or unbranched hydrocarbon chain having 1 to 5 carbon atoms, preferably 2 or 3 carbon atoms. 6 Particular preference is given to vulcanizable rubber compounds according to the invention, in which is preferably a branched or unbranched hydrocarbon chain having 2 or 3 carbon atoms, particularly preferably a branched or unbranched hydrocarbon chain having 3 carbon atoms.

[0038] The polyether chain X contains x repeating units. Vulcanizable rubber compounds according to the invention in which x is in the range of 2 to 15 are preferred.

[0039] In each unit of the polyether chain X, i.e., the different monomer units identified herein by serial number i from i=1 to i=x, R 7i and R 8i are essentially independent of each other, specifically, R in each monomer unit 7i and R 8i Not only that, but all R 7i and all R 8i R in each monomer unit i is also independent. Since alkylene oxides with relatively short chain lengths are fundamentally advantageous, 7i and R 8iis in each case independently hydrogen or a methyl group, independent of the other monomer units in the polyether chain. 7i and R 8i Particular preference is given to vulcanizable rubber compounds according to the invention in which at least one of the radicals is in each case hydrogen.

[0040] In this regard, those skilled in the art will appreciate that R 7i and R 8i It will be appreciated that the nature of the radicals will depend inter alia on the chemical nature of the compounds used to prepare the polyetheramine, in particular the alkylene oxides used, and that more complex polyetheramines will be obtained, especially when different alkylene oxides are mixed together during the preparation of the polyetheramine.

[0041] According to the inventors, the polyether chain is represented by formula IV: IV)-(CHR 7i -CH2-O)- (In the formula, R 7i is preferably the same for all first monomer units i1, and R 7i is particularly preferably a methyl group for all first monomer units i1). and / or The polyether chain has the formula V): V)-(CH2-CH2-O)- and / or The polyether chain has the formula VI): VI)-(CH2-CHR 8i -O)- (In the formula, R 8i is preferably the same for all third monomer units i3, and R 8i is particularly preferably a methyl group for all third monomer units i3). and one or more third monomer units i3 of Preference is given to vulcanizable rubber compounds according to the invention in which the polyether chains preferably consist of these monomer units.

[0042] Regarding these monomer units, the vulcanizable rubber compound according to the present invention is basically preferred in which the number of first monomer units i1 in the polyether chain x1 is in the range of 1 to 7, preferably in the range of 2 to 6, particularly preferably in the range of 2 to 5, and / or the number of second monomer units i2 in the polyether chain x2 is in the range of 1 to 15, preferably in the range of 2 to 12, particularly preferably in the range of 3 to 10, and / or the number of third monomer units i3 in the polyether chain x3 is in the range of 1 to 7, preferably in the range of 2 to 6, particularly preferably in the range of 2 to 5. In this regard, the polyether chain x 1 / 3 Particularly preferred is a vulcanizable rubber compound according to the present invention, wherein the total number of first monomer units i1 and third monomer units i3 is in the range of 2-10, preferably 3-7.

[0043] In this context, firstly, most preferred are vulcanizable rubber compounds according to the invention in which the polyether chains consist preferably to an extent of more than 50%, particularly preferably to an extent of more than 75% and particularly preferably substantially completely of first monomer units i1, the number of first monomer units i1 in the polyether chain x1 being in the range from 1 to 5, preferably in the range from 2 to 4. Corresponding polyetheramines are commercially available, for example under the trade name Jeffamine D-230, in which x1 is about 2.5.

[0044] Additionally or alternatively, vulcanizable rubber compounds according to the invention having mixed polyether chains are also particularly preferred, i.e., the polyether chains comprise two or more, preferably three or more, monomer units selected from the group consisting of the first monomer unit i1, the second monomer unit i2, and the third monomer unit i3, and the polyether chains preferably consist of these monomer units. Relevant for most applications are vulcanizable rubber compounds according to the invention in which at least some, preferably all, of the two or more monomer units are randomly distributed in the polyether chain.

[0045] For mixed polyether chains, first, polyether chain x 1 / 3 Most particularly preferred are vulcanizable rubber compounds according to the invention, in which the total number of first and third monomer units i1 and i3 in the polyether chain x2 is in the range of 2 to 5, and the number of second monomer units i2 in the polyether chain x2 is in the range of 7 to 12. Corresponding polyetheramines are commercially available, for example, under the trade name Jeffamine e ED-600, in which x2 is about 9 and x 1 / 3 is about 3.6.

[0046] For mixed polyether chains, in addition or instead, polyether chain x 1 / 3 Also most particularly preferred are vulcanizable rubber compounds according to the invention, in which the total number of first and third monomer units i1 and i3 in the polyether chain x2 is in the range of 4 to 8, and the number of second monomer units i2 in the polyether chain x2 is in the range of 10 to 15. Corresponding polyetheramines are commercially available, for example, under the trade name Jeffamine e ED-900, in which x2 is about 12.5 and x 1 / 3 is about 6.

[0047] The present inventors believe that the use of such polyetheramines, particularly the commercial products Jeffamine D-230 and ED-600, which are typical representatives thereof, is preferred for achieving the objects of the present invention.

[0048] Thus, one or more polyetheramines may be polyetheramines of formula VII): VII) H2N-(CH(CH3)-CH2-O) x1 -CH2CH(CH3)-NH2 (wherein x1 is in the range of 2 to 6, preferably in the range of 2 to 5, particularly preferably in the range of 2 to 4, and most preferably in the range of 2 to 3), polyetheramines of formula VIII): VIII) H2N-X-CH2CH(CH3)-NH2 (Wherein X is Formula IV b ) the first monomer unit i 1b : IV b )-(CH(CH3)-CH2-O)-, Formula V b ) the second monomer unit i 2b : V b )-(CH2-CH2-O)-, and Equation VI b ) the third monomer unit i 3b : VI b )-(CH2-CH(CH3)-O)- a polymer chain consisting of two or more types of monomer units selected from the group consisting of Polyether chain x 1b / 3b The first monomer unit i in 1b and the third monomer unit i 3b The total number of polyether chains x is in the range of 2 to 5. 2b The second monomer unit i in 2b The number of (ranges from 8 to 10) Particularly preferred are vulcanizable rubber compounds according to the invention selected from the group consisting of:

[0049] Also preferred are vulcanizable rubber compounds according to the invention in which, based on the preparation or preparability of the polyetheramines, one or more polyetheramines are preparable by polymerization of alkylene oxides followed by amination, the alkylene oxides being preferably selected from the group consisting of butylene oxide, ethylene oxide, propylene oxide, and mixtures of these compounds, preferably propylene oxide. Additionally or alternatively, particularly preferred are vulcanizable rubber compounds according to the invention in which one or more polyetheramines are saturated compounds.

[0050] The polyetheramines preferably used are compounds with a relatively short chain length. In particular, vulcanizable rubber compounds according to the invention are particularly preferred, in which the weight-average molar mass of one or more polyetheramines is in the range of 100 to 800 g / mol, preferably in the range of 130 to 650 g / mol, particularly preferably in the range of 190 to 400 g / mol.

[0051] To further optimize the properties of the vulcanizable rubber compounds according to the invention and the vulcanizates producible therefrom, the inventors believe that different polyetheramines can be combined, and in particular preferred polyetheramine combinations such as can be achieved by combining, for example, the commercially available products Jeffamine D-230 and ED-600. Thus, vulcanizable rubber compounds according to the invention that contain two or more different polyetheramines are preferred.

[0052] Regardless of the exact chemical nature of the polyetheramines, the inventors have been able to identify particularly advantageous parts by weight of these components, which allow the above-mentioned objectives to be particularly well achieved. Specifically, preferred vulcanizable rubber compounds according to the invention contain one or more polyetheramines in a total amount ranging from 0.2 to 8 phr, preferably from 0.4 to 6 phr.

[0053] The vulcanizable rubber compound according to the present invention additionally contains an LTG diene rubber. The term "LTG diene rubber" means "low Tg" diene rubber and is used in the context of the present invention to specifically identify and distinguish certain butadiene and styrene-butadiene rubbers having low glass transition temperatures from other diene rubbers.

[0054] LTG diene rubbers are butadiene rubbers and / or styrene-butadiene rubbers having a glass transition temperature Tg, measured by DSC, in the range of -120°C to -30°C, which is lower than that of common BR and SBR rubbers. Corresponding BR and SBR rubbers are known in principle to those skilled in the art and are commercially available. Corresponding SBR LTG rubbers are available, for example, under the trade names Sprintan SLR3402 (from Trinseo) or Nipol NS612 (from Zeon). A suitable BR LTG rubber is available, for example, under the trade name PBT030 (from Zeon). Information on the technical background is disclosed, for example, in EP 2 853 558 A1.

[0055] In the context of the present invention, the glass transition temperature Tg is measured in the customary manner by dynamic scanning calorimetry (DSC, calibrated DSC with cryogenic device, calibration according to instrument type and manufacturer's instructions, sample in an aluminium crucible with an aluminium lid, cooling at 10°C / min to a temperature below -120°C) according to DIN 53765:1994-03 or ISO 11357-2:1999-03.

[0056] In this regard, the inventors have succeeded in identifying particularly preferred LTG polybutadienes for obtaining vulcanizable rubber compounds according to the invention which have a particularly excellent property profile.

[0057] With regard to the glass transition temperature, preference is given to vulcanizable rubber compounds according to the invention, in which the glass transition temperature Tg, measured by DSC, of ​​the one or more LTG diene rubbers is in the range of −100° C. to −30° C., preferably −95° C. to −30° C., particularly preferably −95° C. to −45° C., most preferably −95° C. to −55° C., and especially preferably −85° C. to −55° C. Additionally or alternatively, preference is given to vulcanizable rubber compounds according to the invention, in which the glass transition temperature, measured by DSC, of ​​the one or more LTG diene rubbers is −40° C. or lower, preferably −50° C. or lower.

[0058] In this regard, vulcanizable rubber compounds according to the invention are particularly preferred, in which one or more LTG diene rubbers are selected from the group consisting of styrene-butadiene rubbers having a glass transition temperature Tg, measured by DSC, in the range of -120°C to -30°C. Additionally or alternatively, vulcanizable rubber compounds according to the invention are preferred, in which one or more LTG diene rubbers are selected from the group consisting of solution-polymerized styrene-butadiene rubbers, preferably anionically polymerized solution-polymerized styrene-butadiene rubbers. Vulcanizable rubber compounds according to the invention are preferred, in which at least one, preferably all, of the LTG diene rubbers are selected from the group consisting of styrene-butadiene rubbers having a mass proportion of units derived from styrene in the range of 10% to 30%, preferably in the range of 15% to 25%.

[0059] The present inventors have found that the use of certain functionalized LTG diene rubbers results in particularly effective vulcanizable rubber compounds according to the present invention. Corresponding LTG diene rubbers are disclosed, for example, in EP 2 853 558 A1. Functionalization may be mono- or polyfunctionalized and may occur along the polymer chain and / or at the chain end. Therefore, preferred vulcanizable rubber compounds according to the present invention are those in which at least one, preferably all, of the LTG diene rubbers are selected from the group consisting of butadiene rubber and styrene-butadiene rubber functionalized with phthalocyanine groups, hydroxyl groups, epoxy groups, and / or silane-sulfide groups, preferably styrene-butadiene rubber. Particularly preferred are vulcanizable rubber compounds according to the present invention are those in which at least one, preferably all, of the LTG diene rubbers are selected from the group consisting of butadiene rubber and styrene-butadiene rubber functionalized with hydroxyl groups, preferably styrene-butadiene rubber.

[0060] The weight-average molar mass Mw is advantageously within the ranges specified as preferred for other diene rubbers. Thus, preferred are vulcanizable rubber compounds according to the invention in which one or more LTG diene rubbers have a weight-average molar mass Mw, measured by GPC, in the range of 150,000 to 5,000,000 g / mol, preferably in the range of 250,000 to 2,500,000 g / mol, particularly preferably in the range of 300,000 to 1,500,000 g / mol. Particularly preferred are vulcanizable rubber compounds in which, for the BR LTG rubbers, one or more butadiene rubbers have a weight-average molar mass Mw, measured by GPC, in the range of 200,000 to 2,000,000 g / mol, preferably in the range of 250,000 to 1,000,000 g / mol, particularly preferably in the range of 300,000 to 750,000 g / mol.

[0061] According to the inventors, it is advantageous if the vulcanizable rubber compound contains a relatively large amount of LTG diene rubber, with the proportion of other diene rubbers being correspondingly low. Therefore, preferred are vulcanizable rubber compounds according to the invention which contain one or more LTG diene rubbers in a total amount by weight ranging from 50 to 100 phr, particularly preferably from 60 to 98 phr, most preferably from 70 to 95 phr.

[0062] In addition to the diene rubber, filler, polyetheramine, and LTG diene rubber, additional typical ingredients may be used in the vulcanizable rubber compound of the present invention, for example, to influence the physicochemical properties, such as processing and vulcanization properties, of the vulcanizable rubber compound or to optimize the mechanical properties of the vulcanizates producible therefrom.

[0063] In this respect, first preference is given to vulcanizable rubber compounds according to the invention which comprise one or more additional added substances, preferably selected from the group consisting of reinforcing resins, coupling agents and plasticizers, preferably comprising the additional added substances in a total amount of parts by weight ranging from 10 to 100 phr, preferably from 20 to 80 phr, particularly preferably from 30 to 60 phr.

[0064] Examples that may be mentioned are vulcanizable rubber compounds according to the invention in which the reinforcing resin is selected from the group consisting of resorcinol-formaldehyde resins, in particular resorcinol-hexamethoxymethylmelamine resins (HMM) or resorcinol-hexamethylenetetramine resins (HEXA), and modified phenolic resins. Those skilled in the art of rubber processing can easily distinguish resins from diene rubbers, and in practice, this is done primarily by their average molar mass. In this regard, examples that may be mentioned are vulcanizable rubber compounds according to the invention in which one or more additional resins have a weight-average molar mass Mw, measured by GPC, in the range of 200 to 50,000 g / mol, preferably in the range of 400 to 40,000 g / mol, particularly preferably in the range of 600 to 30,000 g / mol, and most particularly preferably in the range of 800 to 20,000 g / mol.

[0065] An example that may also be mentioned is a vulcanizable rubber compound according to the invention, in which the coupling agent is selected from the group consisting of 3-mercaptopropyltriethoxysilane, 3-thiocyanatopropyltrimethoxysilane, and 3,3'-bis(triethoxysilylpropyl) polysulfides having 2 to 8 sulfur atoms, preferably comprising the coupling agent in a total part by weight ranging from 0.2 to 30 phf, preferably from 1 to 15 phf.

[0066] Further examples that may be mentioned are vulcanizable rubber compounds according to the invention, in which the plasticizer is selected from the group consisting of mineral oils, synthetic plasticizers, fatty acids, fatty acid derivatives, plasticizer resins, factices, glycerides, terpenes, biomass-to-liquid oils (BTL oils) and rubber-to-liquid oils (RTL oils), preferably in a total weight range of 1 to 100 phr, preferably in the range of 10 to 80 phr, particularly preferably in the range of 20 to 60 phr.

[0067] Preferred are vulcanizable rubber compounds according to the invention which additionally or alternatively comprise one or more additional additives, preferably selected from the group consisting of methylene donors, antioxidants such as N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD), N,N'-diphenyl-p-phenylenediamine (DPPD), N,N'-ditolyl-p-phenylenediamine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ), activators such as zinc oxide and fatty acids, waxes, chewing aids such as 2,2'-dibenzamidodiphenyl disulfide (DBD), and processing aids. Preference is given to vulcanizable rubber compounds according to the invention which comprise additional additives in total parts by weight in the range of 0.1 to 20 phr, preferably in the range of 0.5 to 15 phr, particularly preferably in the range of 1 to 10 phr.

[0068] In terms of vulcanization behavior, preference is given to vulcanizable rubber compounds according to the invention which contain 0.5 to 8.0 phr of sulfur, preferably 0.8 to 6 phr, particularly preferably 1 to 4 phr. In this regard, preference is also given to vulcanizable rubber compounds according to the invention which additionally or instead contain additional vulcanization components, which additional vulcanization components are selected from the group consisting of crosslinkers, vulcanization retarders, and vulcanization accelerators, such as thiazole accelerators, mercapto accelerators, sulfenamide accelerators, thiocarbamate accelerators, thiuram accelerators, thiophosphate accelerators, thiourea accelerators, xanthate accelerators, or guanidine accelerators.

[0069] It is particularly preferred to omit guanidine accelerators, especially diphenylguanidine.Thus, vulcanizable rubber compounds according to the invention are preferred which contain not more than 2 phr, preferably not more than 1 phr, particularly preferably not more than 0.5 phr, and most particularly preferably essentially 0 phr of guanidine accelerators, especially diphenylguanidine.

[0070] The inventors have succeeded in identifying additional components that are used in combination with polyetheramines and LTG diene rubbers to produce particularly advantageous vulcanizable rubber compounds and vulcanizates according to the invention. This results in particularly advantageous rolling resistance and favorable braking properties, thereby resolving the conflict of objectives in this regard in a particularly advantageous manner. These advantageously used components are a specific class of resins, namely hydrocarbon resins, and the advantageous effects are particularly evident when the weight percentage of said resin is high. Therefore, particularly preferred are vulcanizable rubber compounds according to the invention that further comprise the following components: d) one or more hydrocarbon resins in a total weight part ranging from 10 to 140 phr.

[0071] Those skilled in the art will understand that hydrocarbon resins are resins containing carbon and hydrogen atoms, but may also contain small amounts of heteroatoms, particularly oxygen atoms, depending in particular on the raw materials and processes used for their production, and the mass proportion of heteroatoms in the hydrocarbon resin is preferably 5% or less, particularly preferably 1% or less, most preferably 0.5% or less, and especially preferably 0.1% or less, based on the mass of the hydrocarbon resin. Suitable hydrocarbon resins are disclosed, for example, in DE 10 2015 210 840 A1.

[0072] Preferred are vulcanizable rubber compounds according to the invention, wherein the one or more hydrocarbon resins are selected from the group consisting of aromatic and aliphatic hydrocarbon resins, preferably terpene, C5, C9, coumarone-indene and dicyclopentadiene (DCPD) resins, and aromatic resins prepared from α-methylstyrene and / or styrene, and copolymers of monomers of these resin types, particularly preferably aromatic resins prepared from α-methylstyrene and / or styrene.

[0073] Particularly preferred is a vulcanizable rubber compound according to the invention, wherein the one or more hydrocarbon resins are selected from the group consisting of aliphatic C5 resins and α-methylstyrene and / or styrene hydrocarbon resins, preferably α-methylstyrene and / or styrene hydrocarbon resins, preferably α-methylstyrene.

[0074] Preferred are vulcanizable rubber compounds according to the invention, in which the one or more hydrocarbon resins have a weight-average molar mass Mw, measured by GPC, in the range from 500 to 4000 g / mol, preferably in the range from 1000 to 3000 g / mol, particularly preferably in the range from 1500 to 2500 g / mol. Additionally or alternatively, preferred are vulcanizable rubber compounds according to the invention, in which the one or more hydrocarbon resins have an average molar mass Mz (centrifugally averaged) in the range from 500 to 10000 g / mol, particularly preferably in the range from 750 to 5000 g / mol, most particularly preferably in the range from 1000 to 4000 g / mol, and especially preferably in the range from 1250 to 3000 g / mol. Additionally or alternatively, preferred are vulcanizable rubber compounds according to the invention, wherein the one or more hydrocarbon resins have a softening point according to ASTM E28 (Ring and Ball) in the range of 10°C to 180°C, preferably in the range of 60°C to 150°C, particularly preferably in the range of 70°C to 120°C, most preferably in the range of 80°C to 99°C.

[0075] Furthermore, the inventors have succeeded in identifying particularly suitable parts by weight of the hydrocarbon resin. In particular, preferred are vulcanizable rubber compounds according to the invention, which contain one or more hydrocarbon resins in a total amount of parts by weight ranging from 20 to 120 phr, preferably from 25 to 110 phr, and particularly preferably from 30 to 100 phr. Additionally or alternatively, preferred are vulcanizable rubber compounds according to the invention, in which the mass proportion of the one or more hydrocarbon resins is 30% or more, preferably 60% or more, particularly preferably 90% or more, and most particularly preferably substantially 100%, based on the total mass of all plasticizers and resins in the vulcanizable rubber compound.

[0076] Vulcanizates and rubber articles can be produced from the vulcanizable rubber compounds according to the invention in a conventional manner. The corresponding processes for producing vulcanizates or rubber articles may, in addition to producing the vulcanizable rubber compounds according to the invention, additionally comprise, for example, the following steps: x) vulcanizing the vulcanizable rubber compound according to the invention, preferably as part of a rubber blank, particularly preferably as part of an unvulcanized vehicle tire blank, to obtain a vulcanizate, preferably as part of a rubber product, preferably as part of a pneumatic vehicle tire.

[0077] Here, the vulcanizable rubber compounds according to the invention are vulcanized by processes customary in the tire industry, for example by sulfur-based crosslinking.

[0078] The present invention therefore also relates to vulcanizates producible or produced by vulcanization of the vulcanizable rubber compound according to the invention. In this respect, preference is given to vulcanizates according to the invention that are producible by vulcanization at temperatures in the range from 130°C to 200°C, preferably in the range from 150°C to 180°C.

[0079] The present invention therefore also relates to a rubber product comprising the vulcanizate according to the invention. Examples that may be mentioned are rubber products according to the invention selected from the group consisting of shoe soles, drive belts, hoses, conveyor belts and belts. However, in virtually all cases, the rubber product according to the invention is preferred to be a vehicle tire, preferably a pneumatic vehicle tire, which preferably comprises a vulcanizate according to the invention in its tread.

[0080] Finally, the use of the vulcanizable rubber compound according to the invention and / or the vulcanizate according to the invention in the manufacture of rubber products, in particular vehicle tyres, is also disclosed.

[0081] Hereinafter, the present invention and preferred embodiments thereof will be described in more detail and illustrated with reference to experiments. [Example]

[0082] A. Manufacturing of vulcanizable rubber compounds: The vulcanizable rubber compounds were prepared in a laboratory tangential mixer using conventional processes and under conventional conditions in the rubber industry in three stages, including first preparing a base mixture containing all the ingredients except the vulcanization system (sulphur and substances influencing vulcanization) in one or more mixing stages, to which the vulcanization system was then added to obtain the final compound.

[0083] The materials used in this regard are listed in Table 1.

[0084] [Table 1]

[0085] [Table 2]

[0086] Using each vulcanizable rubber compound, the test was carried out at 160°C to 170°C under pressure. 95 -t 100 Test specimens were prepared by vulcanization after the rheological properties (measured using a moving die rheometer according to ASTM D5289-19 / ISO6502) were measured. The test specimens were then subjected to the measurement of material properties typical in the rubber industry using the test methods specified in Section B.

[0087] B. Measurement of physicochemical properties of vulcanizates: The following physicochemical properties were measured for the vulcanizable rubber compounds and vulcanizates produced therefrom using the measurement methods listed in Table 2:

[0088] [Table 3]

[0089] C. First series of tests: In the first series of tests, nine vulcanizable rubber compounds were prepared, the compositions of which are listed in Table 3.

[0090] [Table 4]

[0091] [Table 5]

[0092] The parts by weight of polyetheramine were adjusted in each case so that a constant molar amount was introduced.

[0093] The material properties measured for the relevant vulcanizates are summarized in Table 4.

[0094] [Table 6]

[0095] The results of the first series of tests according to Table 4 reveal that polyetheramines 1 and 2 exhibit a beneficial acceleration effect, which is reflected in the shortening of t10 and t90 times. This means that a beneficial acceleration effect can be advantageously achieved without the use of DPG, and that shorter vulcanization times can be advantageously achieved.

[0096] When SSBR1 is used, the use of Polyetheramine 1 in V2 and Polyetheramine 2 in V3 results in an undesirable decrease in RB70°C compared to V1. On the other hand, the use of SSBR2 in E1 and E2 and SSBR3 in E3 and E4 consistently improves these values ​​compared to the DPG-based references V4 and V5, respectively. Furthermore, it is clear that the use of Polyetheramine 1 in V2 and Polyetheramine 2 in V3 results in an undesirable increase in E' (0.15%) and E' (0.15%) - E' (8%) compared to V1, suggesting an undesirable increase in filler-filler interactions (the Payne effect). In contrast, inventive samples E1 to E4, surprisingly, the values ​​remain substantially constant or even decrease compared to V4 and V5, within the limits of measurement precision. This means that this experiment demonstrates a clear improvement in rolling resistance for the inventive samples.

[0097] Furthermore, when SSBR1 is used, the use of Polyetheramine 1 in V2 and Polyetheramine 2 in V3 leads to an undesirable decrease in M300 compared to V1, whereas the inventive samples advantageously increase this value compared to the respective reference samples, meaning that the vulcanizates are stiffer and exhibit better handling properties.

[0098] Additionally, the samples of the present invention surprisingly showed improved wear resistance, whereas the improvement was not clear in samples V1 to V3, and in some cases it is even suspected that wear resistance may have worsened.

[0099] D. Second series of tests: In a second series of tests, eight vulcanizable rubber compounds were prepared, the compositions of which are listed in Table 5.

[0100] [Table 7]

[0101] The material properties measured for the relevant vulcanizates are summarized in Table 6.

[0102] [Table 8]

[0103] The results of the second series of tests according to Table 6 show the accelerating effect of Polyetheramine 1.

[0104] Comparison of Samples V6 and E5 reveals that in the inherently advantageous inventive samples with high filler content and high plasticizer content of the plasticizer oil, replacing DPG with Polyetheramine 1 can increase E' (0.15%) - E' (8%), suggesting an undesirable increase in filler-filler interactions (the Payne effect). In contrast, the addition of a hydrocarbon resin advantageously results in a decrease, an indicator of improved rolling resistance. Consistent with this finding, the use of Polyetheramine 1 also results in improvements in the inventive samples containing hydrocarbon resin, in the form of decreased values ​​of tan d max (DKF) and tan d (55°C, temperature sweep, constant force), also indicators of improved rolling resistance.

[0105] Additionally, the samples of the present invention containing hydrocarbon resins exhibit improved braking performance as evidenced by increased tan d(0°C).

Claims

1. 1. A vulcanizable rubber compound comprising: a) one or more LTG diene rubbers selected from the group consisting of butadiene rubber and styrene-butadiene rubber having a glass transition temperature Tg in the range of −120° C. to −30° C. as measured by DSC; b) one or more fillers selected from the group consisting of silica; c) one or more polyetheramines in a total weight range of 0.1 to 10 phr, Formula I): I) R １ R ２ N-(R ５ ) ｍ -X-R ６ -NR ３ R ４ and wherein in formula I) R １ , R ２ , R ３ , and R ４ are each independently hydrogen or a branched or unbranched hydrocarbon radical having 1 to 10 carbon atoms, m is 0 or 1, and R ５ and R ６ are each independently a branched or unbranched hydrocarbon chain having 1 to 10 carbon atoms; X is a group of formula II): II) -(CHR ７ｉ -CHR ８ｉ -O) ｘ - In formula II), x is in the range of 2 to 30, and R ７ｉ and R ８ｉ is in each occurrence independently and independently of other monomer units in the polyether chain, hydrogen or a hydrocarbon radical having 1 or 2 carbon atoms; d) one or more diene rubbers different from the LTG diene rubber; 1. A vulcanizable rubber compound comprising:

2. The diene rubber contains styrene-butadiene rubber, and / or the diene rubber contains butadiene rubber, 2. The vulcanizable rubber compound according to claim 1, further comprising natural polyisoprene and / or synthetic polyisoprene as diene rubber.

3. 3. The vulcanizable rubber compound of claim 1 or 2, comprising said one or more fillers in a total parts by weight ranging from 5 to 250 phr.

4. R in each monomer unit i ７ｉ and R ８ｉ 4. The vulcanizable rubber compound of claim 1, wherein each occurrence of is independently hydrogen or a methyl group, independent of other monomer units in the polyether chain.

5. The polyether chain is represented by formula IV: IV)-(CHR ７ｉ -CH ２ -O)- and / or The polyether chain has the formula V: V)-(CH ２ -CH ２ -O)- one or more second monomer units i ２ and / or The polyether chain is represented by formula VI: VI)-(CH ２ -CHR ８ｉ -O)- one or more third monomer units i ３ The vulcanizable rubber compound according to any one of claims 1 to 4, comprising:

6. the one or more polyetheramines polyetheramines of formula VII): VII)H ２ N-(CH(CH ３ )-CH ２ -O) ｘ１ -CH ２ CH(CH ３ )-NH ２ (In the formula, x １ is in the range of 2 to 6) and polyetheramines of formula VIII): VIII)H ２ N-X-CH ２ CH(CH ３ )-NH ２ (Wherein X is Formula III ｂ ) the first monomer unit i １ｂ : III ｂ )-(CH(CH ３ )-CH ２ -O)- Formula IV ｂ ) the second monomer unit i ２ｂ : IV ｂ )-(CH ２ -CH ２ -O)-, and Formula V ｂ ) the third monomer unit i ３ｂ : V ｂ )-(CH ２ -CH(CH ３ )-O)- a polyether chain consisting of two or more types of monomer units selected from the group consisting of The polyether chain x １ｂ／３ｂ The first monomer unit i in １ｂ and a third monomer unit i ３ｂ The total number of the polyether chains x is in the range of 2 to 5, ２ｂ The second monomer unit i in ２ｂ the number of is in the range of 8 to 10) and The vulcanizable rubber compound according to any one of claims 1 to 5, selected from the group consisting of:

7. 7. The vulcanizable rubber compound according to any one of claims 1 to 6, wherein the LTG diene rubber is selected from the group consisting of butadiene rubber and styrene-butadiene rubber functionalized with phthalocyanine groups and / or hydroxyl groups and / or epoxy groups and / or silane sulfide groups.

8. d) one or more hydrocarbon resins in a total weight range of 10 to 140 phr 8. The vulcanizable rubber compound according to claim 1, further comprising:

9. A vulcanizate producible or produced by vulcanization of the vulcanizable rubber compound according to any one of claims 1 to 8.

10. A rubber product, in particular a pneumatic vehicle tire, comprising the vulcanizate of claim 9.

Images