Rubber composition containing additives and use thereof

Abstract

The present invention relates to a rubber composition comprising a rubber and at least one rubber additive, the at least one rubber additive comprising a fatty acid ester, the fatty acid ester comprising at least one C8 to C 22 The present invention relates to a rubber composition, characterized in that it is produced from a fatty acid and at least one compound selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide. The present invention further relates to the use of the rubber additive in the rubber composition and to a tire, at least one component of which is at least partially made from the rubber composition according to the invention, as well as to a process for its manufacture.

Description

[Technical field]

[0001] FIELD OF THEINVENTION The present invention relates to a rubber composition comprising a rubber and at least one rubber additive based on a fatty acid ester. The present invention further relates to the use of the rubber additive in the rubber composition and to a tire, at least one component of which is at least partially made from the rubber composition according to the invention, as well as to a process for its manufacture. [Background technology]

[0002] 2. Background of the Invention In recent years, the development of tread compounds for all-season and winter tires is driven by the improvement of the properties of tire grip (traction) and tire wear (stiffness) at low temperatures. To achieve this, the respective rubber composition contains, for example, long-chain-length rubbers. This results in poor processability of the rubber compound (high viscosity, lack of green strength). In the rubber industry, numerous processing aids exist, but when they are used, at least one other property is impaired, for example low stiffness (= high tire wear, poor handling) or high rolling resistance. For this reason, (cold) plasticizers are typically added to rubber formulations.

[0003] This compromise between processability and the performance criteria of tire grip / tire wear at low temperatures and tire rolling resistance is currently no longer acceptable in the development of tire compounds, because safety aspects (short braking distances at low temperatures) and particulate arguments (tire wear, microplastics) are arguments regarding effective marketing and therefore have a decisive impact on tire sales.

[0004] US 2017 / 0051134 A1 relates to a tire rubber composition having improved dispersion of silica in the rubber and tires produced therefrom. The composition includes a rubber compound and a glycerol fatty acid monoester and silica.

[0005] US 2019 / 0233622 A1 discloses ethoxylated glycerol esterified with fatty acids for use in rubber compositions for tires with improved processability and wear resistance (see claim 1, paragraphs

[0001] to

[0003] ). Tire wear is clearly determined by the glass transition temperature of the rubber (tan δ max peak, DMA). US 2019 / 0233622 A1 does not describe an improvement in the rolling resistance of the tires produced. The rolling resistance is affected by substances that change the tan δ at 60°C. Wear and rolling resistance are independent variables, and a person skilled in the art would not necessarily take an improvement in one of them to mean an improvement in the other.

[0006] The object of the present invention is to develop new additives for winter and all-season tires which improve the processing properties of the rubber compositions used for the manufacture of these tires, while at the same time the other performance properties of the tire, in particular the properties relating to rolling resistance and grip on snow and in dry conditions, as well as tire wear, are not impaired or are at least partially improved.

[0007] A further object of the present invention is to improve the extrusion characteristics and surface and edge condition of extrudates (Garvey die) made from the rubber composition. Summary of the Invention [Means for solving the problem]

[0008] Summary of the Invention The object is to provide a rubber composition comprising a rubber and at least one rubber additive, the at least one rubber additive comprising a fatty acid ester, the fatty acid ester being at least one C8-C 22 This is achieved according to the present invention by a rubber composition, which is produced from a fatty acid and at least one compound selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide.

[0009] A further aspect of the present invention is the use of at least one C8-C olefin copolymer as a rubber additive in a rubber composition to improve the Mooney viscosity and / or extrusion properties of the rubber composition, and / or to improve at least one of the wear, wet grip and / or rolling resistance of a tire made from the rubber composition. 22 The present invention relates to the use of fatty acid esters of fatty acids and at least one compound selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide.

[0010] A further aspect of the present invention relates to a process for producing a tire, characterised in that one or more components of the tire are made from the rubber composition defined herein, and that the rubber composition is cured.

[0011] A further aspect of the present invention relates to a tire, preferably an all-season tire or a winter tire, at least one component of which is at least partially made from the rubber composition defined herein, said component being in particular the tread.

[0012] Preferred embodiments are the subject matter of the dependent claims.Embodiments of the invention may comprise and in particular consist of the elements described below. [Brief description of the drawings]

[0013] [Figure 1] Figures 1a-d show different extrudates (after 24 h and 1 week at 60 1 / min and 15 1 / min), which were produced from rubber compositions A and B described in Example 3 (Figure 1a: after 24 h at 15 1 / min; Figure 1b: after 24 h at 60 1 / min; Figure 1c: after 1 week at 15 1 / min; Figure 1d: after 1 week at 60 1 / min). [Diagram 2]Figure 2a-b shows different extrudates after 24 h (at 60 1 / min and 15 1 / min), which were produced from rubber compositions C and D described in Example 4 (Figure 2a: after 24 h at 15 1 / min; Figure 2b: after 24 h at 60 1 / min). [Diagram 3] Figure 3a-d shows different extrudates (after 24 h and 1 week at 60 1 / min and 15 1 / min), which were produced from rubber compositions E and F described in Example 5 (Figure 3a: after 24 h at 15 1 / min; Figure 3b: after 24 h at 60 1 / min; Figure 3c: after 1 week at 15 1 / min; Figure 3d: after 1 week at 60 1 / min). [Figure 4] Figure 4a-b shows different extrudates (at 15 1 / min and 60 1 / min), which were produced from rubber compositions G-J described in Example 6 (Figure 4a: after 24 h at 15 1 / min; Figure 4b: after 24 h at 60 1 / min). [Diagram 5] FIG. 5 shows the progression of material pressure for rubber compositions GJ from Example 6 at different shear rates. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Detailed Description of the Invention The present inventors have surprisingly found that at least one C8-C 22 It has been found that fatty acid esters formed from fatty acids (fatty acid component, defined in more detail below) and at least one compound selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide (polyol component, defined in more detail below) have beneficial properties in rubber compositions.

[0015] The constituents of the rubber composition according to the invention are described in more detail below. All statements also apply to the tire according to the invention, at least one component of which consists at least in part of the rubber composition according to the invention, to its manufacture and to the use according to the invention of the fatty acid esters defined herein.

[0016] The specifications phr (parts by weight per hundred parts of rubber) used in this document are quantity specifications for compound formulations that are common in the rubber industry. The percentages of parts by weight of individual substances in this document are based on 100 parts by weight of the total mass of all the polymeric and resulting solid rubbers present in the compound.

[0017] Polyol Component The fatty acid ester according to the present invention is produced from at least one compound (polyol component) selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide, and the compound is a C8-C 22 Esterified with fatty acids.

[0018] In certain embodiments, the polyol component has 2 to 8 hydroxyl groups, such as 2 to 6 hydroxyl groups. The polyol component preferably has between 2 and 4 hydroxyl groups. In particularly preferred embodiments, the polyol component used to produce the fatty acid ester has 2 or 3 hydroxyl groups.

[0019] In a preferred embodiment, the polyol component has no aromatic groups.

[0020] In a preferred embodiment, the polyol component according to the present invention consists solely of carbon, hydrogen and oxygen.

[0021] In some embodiments, the fatty acid ester is a C-C 22The fatty acid esters are produced from at least one polyether, such as polyethylene glycol (PEG), polypropylene glycol (PPG) and / or copolymers of ethylene oxide and propylene oxide. The copolymers of ethylene oxide and propylene oxide can be statistical or block copolymers. It is known to those skilled in the art that polyethers with high molar masses are polymolecular, i.e. consist of a distribution of macromolecules with different molar masses. According to the present invention, polyethylene glycol, polypropylene glycol and / or copolymers of ethylene oxide and propylene oxide with average molecular weights in the range of about 200 to 1500 g / mol can be used to produce the fatty acid esters, for example 200 to 800 g / mol, such as about 400 g / mol.

[0022] In one embodiment, the fatty acid ester according to the present invention is a C8-C 22 They are made from polyethylene glycol (PEG), polypropylene glycol (PPG) and / or copolymers of ethylene oxide and propylene oxide esterified with fatty acids.

[0023] In some embodiments, the fatty acid esters according to the present invention are produced from polyethylene glycol or polypropylene glycol.

[0024] In one embodiment, the fatty acid ester is formed from at least one polyethylene glycol or polypropylene glycol having a molecular weight of 200 to 800 g / mol, in particular 400 g / mol to 600 g / mol.

[0025] In one embodiment, the fatty acid ester is formed from at least one polyethylene glycol having a molecular weight of 200 (PEG 200) to 800 g / mol (PEG 800), for example 400 to 600 g / mol, in particular 400 g / mol (PEG 400).

[0026] In a further embodiment, the fatty acid ester is produced from at least one polypropylene glycol having a molecular weight of 200 to 800 g / mol, for example 400 to 600 g / mol, in particular 600 g / mol.

[0027] In one embodiment, the fatty acid ester is produced from at least one statistical copolymer of ethylene oxide and propylene oxide having a molecular weight of 200 to 800 g / mol, for example 400 to 600 g / mol, in particular 400 g / mol. In a preferred embodiment, the statistical copolymer of ethylene oxide and propylene oxide has an ethylene oxide group content of 10 to 30 wt.-%.

[0028] In a further embodiment, the fatty acid ester is produced from at least one block copolymer of ethylene oxide and propylene oxide having a molecular weight of 50 to 4500 g / mol, for example 200 to 3000 and in particular 500 to 2500 g / mol. According to a preferred embodiment, the ethylene oxide / propylene oxide block copolymer has an ethylene oxide group content of 10 to 80 wt.-%, for example 10 to 55 wt.-%. The block copolymer may be constructed with polyoxyethylene groups located in the middle and at both ends of the polypropylene glycol molecule.

[0029] The ethylene oxide / propylene oxide block copolymers used according to the present invention are compounds that are conventional in the trade. They can be produced by reacting polypropylene glycol with ethylene oxide. Examples of ethylene oxide / propylene oxide block copolymers are Pluronic PE polymers from BASF SE, such as Pluronic PE 3100, Pluronic PE 3500, Pluronic PE 4300, Pluronic PE 6100, Pluronic PE 6120, Pluronic PE 6200, Pluronic PE 6400, Pluronic PE 6800, Pluronic PE 8100, Pluronic PE 9200, Pluronic PE 9400, Pluronic PE 10100, Pluronic PE 10300, Pluronic PE 10400 and Pluronic PE 10500. In a further embodiment, the fatty acid ester is produced from at least one C2-C4 alkoxylate of a polyol. Polyol means a substance having at least two free hydroxyl groups. The hydrocarbon portion of the polyol is a group containing carbon and hydrogen, in which at least two carbon atoms are bonded to one hydroxyl group. It may be linear or branched, in particular linear, and may be interrupted by heteroatoms, if desired.

[0030] C2-C4 alkoxylates of polyols are polyols reacted with C2-C4 alkylene oxides, where several reactions can occur one after the other on the hydroxyl groups of the polyol. Examples of C2-C4 alkylene oxides are ethylene oxide, propylene oxide and 1-butene oxide. The reaction of polyols with C2-C4 alkylene oxides is carried out using established processes.

[0031] Mixed C2-C4 alkoxylates may also be used, where a polyol is reacted with a mixture of C2-C4 alkylene oxides (such as a mixture of ethylene oxide with propylene oxide and / or 1-butylene oxide).

[0032] In a preferred embodiment, the fatty acid ester is formed from at least one polyol alkoxylate having up to 10, such as 5 to 10, for example 7, alkylene oxide units.

[0033] The C2-C4 alkoxylates of polyols may have an average molecular weight in the range of about 200 to 1500 g / mol, for example about 200 to 800 g / mol, in particular 300 to 500 g / mol.

[0034] In certain embodiments, the C2-C4 alkoxylate of the polyol has 2 to 8 hydroxyl groups, for example 2 to 6 hydroxyl groups. In a preferred embodiment, the C2-C4 alkoxylate of the polyol used to produce the fatty acid ester has between 2 and 4 hydroxyl groups, for example 2 or 3 hydroxyl groups.

[0035] In a preferred embodiment, the fatty acid ester is formed from at least one polyol ethoxylate having up to 10, such as 5 to 10, for example 7, ethylene oxide units (EO units).

[0036] In a further preferred embodiment, the fatty acid ester is produced from at least one polyol propoxylate having up to 10, such as 5 to 10, for example 7 propylene oxide units (PO units).

[0037] The polyol ethoxylate or polyol propoxylate preferably has between 2 and 4 hydroxyl groups.

[0038] C2-C4 alkoxylated polyols are C2-C 15 It can be a polyol. This means that the polyol has 2 to 15 carbon atoms. 10 The polyol and in particular the C2-C6 polyol is preferably an alkoxylated C2-C 15The polyol used as the polyol component preferably has 2 to 8 hydroxyl groups, for example 2 to 8 and in particular 2 to 4 hydroxyl groups, for example 2 or 3 hydroxyl groups.

[0039] Examples of polyols which may be reacted with the C2-C4 alkylene oxides are ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-propanediol, glycerol, pentaerythritol, dipentaerythritol, tripentaerythritol, trimethylolethane, trimethylolpropane and mixtures thereof. The polyol of the C2-C4 alkoxylate is preferably selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, glycerol and mixtures thereof, and in particular is glycerol.

[0040] Sugar alcohols, such as sorbitol, maltitol, mannitol, xylitol and mixtures thereof, are also C 2~ It can be used as a polyol that can be reacted with C4 alkylene oxide, which has the additional advantage that the fatty acid esters so produced can be produced more sustainably.

[0041] In a preferred embodiment, the polyol component of the fatty acid ester is a material from the group consisting of polyethylene glycol, polypropylene glycol, ethoxylated glycerol, ethoxylated trimethylolpropane, ethoxylated pentaerythritol, ethoxylated sorbitol and / or mixtures thereof.

[0042] In a particularly preferred embodiment, the fatty acid ester is a C-C 22It is produced from fatty acids and ethoxylated glycerol, in particular having up to 10, such as 5 to 10, for example 7, ethylene oxide units. Such glycerol according to the invention is commercially available, for example as Aduxol-Gly-07 from Schaerer & Schlaepfer.

[0043] In some embodiments, only one polyol component (but which contains a high molecular weight alcohol with a molecular weight distribution, such as PEG 400) is used to generate the fatty acid esters.

[0044] In further embodiments, at least two different polyol components are used to produce the fatty acid esters. Thus, for example, a mixture of PEG, PPG and / or PEG-PPG copolymers can be used to produce the fatty acid esters.

[0045] Fatty acid component The fatty acid component according to the present invention is a C8 to C 22 Based on fatty acids. This means that the fatty acids have 8 to 22 carbon atoms. It should be noted that fatty acids usually mean aliphatic saturated and unsaturated carboxylic acids with almost exclusively unbranched carbon chains (see for example Roempp Chemie Lexikon, 9th edition 1990, volume 2, p. 1343). According to the present invention, "fatty acids" also means acids with a degree of unsaturation. Branching or heteroatoms may also be present as long as they do not significantly impair the aliphatic character of the acid.

[0046] The fatty acid component according to the invention therefore comprises at least one saturated or unsaturated, branched or unbranched (= linear) C8-C 22 Based on fatty acids.

[0047] In an embodiment of the invention, the fatty acid component according to the invention consists of a mixture of different fatty acids. The fatty acid component comprises at least two, such as at least three, four or five different C8-C 22 It may contain fatty acids.

[0048] Typical examples of fatty acids which may be used as the fatty acid component in the present invention are octanoic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, palmitoleic acid, heptadecanoic acid, stearic acid, oleic acid, elaidic acid, vaccenic acid, petroselinic acid, linoleic acid, linolenic acid, ricinoleic acid, 12-hydroxystearic acid, arachidic acid, gadoleic acid, gondoic acid, behenic acid, cetoleic acid and erucic acid.

[0049] In a preferred embodiment, the fatty acid moiety according to the present invention consists of carbon, hydrogen and hydrogen only.

[0050] The fatty acid component according to the invention comprises at least one saturated or unsaturated, branched or unbranched (= linear) C 10 ~C 22 It may contain fatty acids.

[0051] The fatty acid component according to the invention preferably comprises at least one C 12 ~C 22 Fatty acids, especially mono- or polyunsaturated, branched or unbranched (= linear) C 16 ~C 20 Contains fatty acids or mixtures thereof.

[0052] In a preferred embodiment, the fatty acid component according to the invention comprises at least one monounsaturated or diunsaturated C 16 ~C 20 Contains fatty acids. Diunsaturated fatty acids are fatty acids whose carbon chains contain two double bonds.

[0053] In a particularly preferred embodiment, the fatty acid component according to the invention comprises at least one monounsaturated C 16 ~C 20 Fatty acids and at least one diunsaturated C 16 ~C 20 Contains fatty acids.

[0054] In a further particularly preferred embodiment, the fatty acid component according to the invention comprises at least one monounsaturated C 16 ~C 20 Fatty acids, at least one diunsaturated C 16 ~C 20 Fatty acids and at least one triunsaturated C 16 ~C 20 Contains fatty acids.

[0055] In a preferred embodiment, the fatty acid component according to the invention comprises at least one C 18 Fatty acids, especially C 18:1 Fatty acids, such as oleic acid, and / or C 18:2 Contains fatty acids. C 18:1 The fatty acid is a fatty acid having 18 carbon atoms, the carbon chain of which has one double bond. 18:2 The fatty acid is a fatty acid having 18 carbon atoms, the carbon chain of which has two double bonds.

[0056] In a preferred embodiment, the fatty acid component according to the invention comprises at least one C 18:1 Fatty acids and at least one C 18:2 Contains fatty acids.

[0057] In a further preferred embodiment, the fatty acid component according to the invention comprises at least one C 18:1 Fatty acids, at least one C 18:2 Fatty acids and at least one C 18:3 Contains fatty acids.

[0058] It is known to those skilled in the art that commercial products used to produce fatty acid esters usually contain a mixture of fatty acids.Furthermore, fatty acids may also be present as industrial fractions, and may accumulate during high-pressure cracking or saponification of natural oils and fats, such as palm oil, palm kernel oil, coconut oil, olive oil, soybean oil, sunflower oil, rapeseed oil or animal fats.

[0059] In one embodiment, the fatty acid component according to the invention is at least 50 wt.-%, such as at least 75 wt.-%, in particular at least 90 wt.-% C-C22 It is produced from a mixture of fatty acids, including fatty acids.

[0060] In one embodiment, the fatty acid component according to the invention has at least 50 wt.-%, such as at least 75 wt.-%, in particular at least 90 wt.-% C 12 ~C 20 It is produced from a mixture of fatty acids, including fatty acids.

[0061] In one embodiment, the fatty acid component according to the invention has at least 50 wt.-%, such as at least 75 wt.-%, in particular at least 90 wt.-% C 16 ~C 20 The mixture of fatty acids is preferably produced from a mixture of fatty acids containing 50 to 100 wt.-%, for example 75 to 100 wt.-%, in particular 90 to 100 wt.-% C 16 ~C 20 Contains fatty acids.

[0062] In one embodiment, the fatty acid component according to the invention is at least 50 wt.-%, such as at least 65 wt.-%, in particular at least 75 wt.-% saturated or mono- or polyunsaturated C 18 It is produced from a mixture of fatty acids, including fatty acids.

[0063] In one embodiment, the fatty acid component according to the invention is 50 to 95 wt.-%, for example 65 to 90 wt.-%, in particular 70 to 85 wt.-% saturated or mono- or polyunsaturated C 18 It is produced from a mixture of fatty acids, including fatty acids.

[0064] The mixture of fatty acids used for production preferably contains at least 1 wt.-% saturated C 18 Fatty acids, 10 wt.-% C 18:1 Fatty acids and / or at least 5 wt.-% C 18:2 Contains fatty acids.

[0065] In one embodiment, the mixture of fatty acids contains at least 50 wt.-% C, such as at least 65 wt.-%, in particular at least 70 wt.-% C 18:1 Contains fatty acids, especially oleic acid.

[0066] In one embodiment, the mixture of fatty acids comprises 50 to 90 wt.-%, for example 65 to 85 wt.-%, in particular 70 to 80 wt.-% C 18:1 Contains fatty acids, especially oleic acid.

[0067] In one embodiment, the mixture of fatty acids comprises 0.1 to 30 wt.-% of C, such as 1 to 15 wt.-%, in particular 5 to 12 wt.-% of C 18:2 Contains fatty acids, especially linoleic acid.

[0068] In a preferred embodiment, the mixture of fatty acids contains 65 to 85 wt.-% C 18:1 Fatty acids and 1–15 wt.-% C 18:2 Contains fatty acids.

[0069] In a further embodiment, the mixture of fatty acids comprises at least 5 wt.-% C, such as at least 10 wt.-%, in particular at least 15 wt.-% C 18:1 Contains fatty acids, especially oleic acid.

[0070] The mixture of fatty acids may contain 5 to 50 wt.-%, for example 10 to 40 wt.-%, in particular 15 to 35 wt.-% C 18:1 It may contain fatty acids, particularly oleic acid.

[0071] The mixture of fatty acids may contain 10 to 90 wt.-%, for example 25 to 75 wt.-%, in particular 40 to 65 wt.-% C 18:2 It may contain fatty acids, especially linoleic acid.

[0072] In a preferred embodiment, the mixture of fatty acids contains 10 to 40 wt.-% C 18:1 Fatty acids and 25-75 wt.-% C 18:2 Fatty acids, e.g., 15-35 wt.-% C18:1 Fatty acids and 40-65 wt.-% C 18:2 Contains fatty acids.

[0073] The mixture of fatty acids may contain 0.1 to 30 wt.-%, for example 1 to 20 wt.-%, in particular 2 to 15 wt.-% C 18:3 It may further comprise a fatty acid.

[0074] In a particularly preferred embodiment, the mixture of fatty acids contains 10 to 40 wt.-% C 18:1 Fatty acids, 25-75 wt.-% C 18:2 Fatty acids and 1–20 wt.-% C 18:3 In particular, the mixture of fatty acids contains 15-35 wt.-% C 18:1 Fatty acids and 40-65 wt.-% C 18:2 Fatty acids and 2–15 wt.-% C 18:3 Contains fatty acids.

[0075] The acid number of the fatty acids used or of the fatty acid mixtures used is preferably from 100 to 300 mg KOH / g, in particular from 150 to 250 mg KOH / g. The acid number is determined according to DIN EN ISO 2114.

[0076] The saponification number of the fatty acid or fatty acid mixture used is preferably 100-300 mg KOH / g, in particular 150-250 mg KOH / g. The saponification number indicates the amount of potassium hydroxide in mg required to saponify 1 g of the sample to be tested. The determination of the saponification number is carried out using DIN EN ISO 3681.

[0077] The iodine value of the fatty acid used or of the fatty acid mixture used is preferably between 10 and 200 g iodine / 100 g, in particular between 50 and 150 g iodine / 100 g. The iodine value indicates the degree of unsaturation of the sample. The determination of the iodine value is carried out using DIN EN ISO 3961 2018-1.

[0078] Fatty acid esters The esterification of the polyol with the fatty acid can be carried out by known methods. Here, as the acid catalyst, for example, hypophosphorous acid, methanesulfonic acid, butanesulfonic acid, p-toluenesulfonic acid, naphthalenesulfonic acid, alkylbenzenesulfonic acid, sulfosuccinic acid and / or mixtures thereof can be used. It is further recommended that the esterification is carried out at high temperatures, for example, at 140 to 250°C, preferably 180 to 240°C. In a preferred embodiment, the fatty acid ester is produced by heating in hypophosphorous acid.

[0079] As noted above, the fatty acid esters may be produced from mixtures of different fatty acids and / or polyols.

[0080] In certain embodiments, the fatty acid esters according to the present invention consist only of carbon, hydrogen and oxygen.

[0081] In one embodiment, the fatty acid ester according to the present invention comprises a C2-C4 alkoxylate of at least one C2-C6 polyol and at least one C 12 ~C 22 Fatty acids, preferably with at least one unsaturated C 16 ~C 20 It is produced from fatty acids.

[0082] The fatty acid esters are preferably partial esters (i.e. not all of the -OH groups of the polyol from which the ester is formed are esterified) and in particular at least 40 wt.-%, for example at least 70 wt.-%, based on the total weight of the partial and full esters, of C8-C 22 It is a fatty acid monoester of a fatty acid or a mixture thereof.

[0083] In certain embodiments, the fatty acid esters according to the present invention consist essentially of fatty acid monoesters.

[0084] In one embodiment, the fatty acid ester according to the present invention comprises a C2-C4 alkoxylate of a C2-C6 polyol and at least one C16 ~C 20 Fatty acids, preferably unsaturated C 16 ~C 20 It is a fatty acid monoester with a fatty acid.

[0085] In a further embodiment, the fatty acid ester according to the invention comprises a polyethylene glycol and at least one C 12 ~C 22 Fatty acids, preferably with at least one unsaturated C 16 ~C 20 It is a fatty acid monoester with a fatty acid.

[0086] In a further embodiment, the fatty acid ester according to the invention comprises polypropylene glycol and at least one C 12 ~C 22 Fatty acids, preferably with at least one unsaturated C 16 ~C 20 It is a fatty acid monoester with a fatty acid.

[0087] In a further embodiment, the fatty acid ester according to the invention comprises a copolymer of ethylene oxide and propylene oxide and at least one C 12 ~C 22 Fatty acids, preferably with at least one unsaturated C 16 ~C 20 It is a fatty acid monoester with a fatty acid. The copolymers of ethylene oxide and propylene oxide can be statistical or block copolymers.

[0088] In one embodiment, the fatty acid ester according to the present invention is a mixture of fatty acid monoesters of polyethylene glycol or polypropylene glycol, wherein the mixture of fatty acids used for the production contains at least 50 wt.-% C 16 ~C 20 Fatty acids, preferably at least 50 wt.-% saturated or (poly)unsaturated C 18The mixture of fatty acids used for the preparation contains 50 to 95 wt.-%, for example 65 to 90 wt.-%, in particular 70 to 85 wt.-% saturated or (poly)unsaturated C 18 The mixture may contain fatty acids. The mixture preferably contains at least 10 wt.-% C 18:1 Fatty acids and / or at least 5 wt.-% C 18:2 Contains fatty acids.

[0089] In a preferred embodiment, the fatty acid ester according to the invention is a mixture of fatty acid monoesters of polyethylene glycol or polypropylene glycol, wherein the mixture of fatty acids used for the production contains 65 to 85 wt.-% C 18:1 Fatty acids and / or 1-15 wt.-% C 18:2 Contains fatty acids.

[0090] In a further preferred embodiment, the fatty acid ester according to the invention is a mixture of fatty acid monoesters of polyethylene glycol or polypropylene glycol, wherein the mixture of fatty acids used for the production contains 10 to 40 wt.-% C 18:1 Fatty acids and / or 25-75 wt.-% C 18:2 Fatty acids and / or 1-20 wt.-% C 18:3 In particular, the mixture of fatty acids contains 15-35 wt.-% C 18:1 Fatty acids and 40-65 wt.-% C 18:2 Fatty acids and 2–15 wt.-% C 18:3 Contains fatty acids.

[0091] In one embodiment, the fatty acid ester according to the present invention is a polyol ethoxylate or polyol propoxylate and a C8-C 22 Fatty acid ester mixture, preferably C 12 ~C 22 It is an ester with a mixture of fatty acid esters.

[0092] In one embodiment, the fatty acid ester according to the invention is an ester of ethoxylated glycerol or trimethylolpropane (which has up to 10, e.g., 5 to 10, ethylene oxide units) with a fatty acid ester mixture, wherein the mixture of fatty acids used for production contains at least 50 wt.-% C 16 ~C 20 Fatty acids, preferably 50-95 wt.-% saturated or unsaturated C 18 Contains fatty acids.

[0093] In a preferred embodiment, the fatty acid ester according to the invention is an ester of ethoxylated glycerol or ethoxylated trimethylolpropane (which has up to 10, for example 5 to 10, ethylene oxide units) with a fatty acid ester mixture, in which the mixture of fatty acids used for the production has a C content of 65 to 85 wt.-%. 18:1 Fatty acids and / or 1-15 wt.-% C 18:2 Contains fatty acids.

[0094] In a further preferred embodiment, the fatty acid ester according to the invention is an ester of ethoxylated glycerol or ethoxylated trimethylolpropane (which has up to 10, for example 5 to 10, ethylene oxide units) with a fatty acid ester mixture, in which the mixture of fatty acids used for the production contains 10 to 40 wt.-% C 18:1 Fatty acids and / or 25-75 wt.-% C 18:2 Fatty acids and / or 1-20 wt.-% C 18:3 Contains fatty acids.

[0095] In a preferred embodiment, the fatty acid ester according to the invention is a monoester of ethoxylated glycerol or ethoxylated trimethylolpropane (which has 5 to 10 ethylene oxide units) with a fatty acid ester mixture, where the mixture of fatty acids used for the production preferably contains at least 50 wt.-% saturated or unsaturated C 18 Fatty acids, especially those with 65-85 wt.-% C 18:1Fatty acids and / or 1-15 wt.-% C 18:2 Contains fatty acids.

[0096] In a further preferred embodiment, the fatty acid ester according to the invention is a monoester of ethoxylated glycerol or ethoxylated trimethylolpropane (which has up to 10, for example 5 to 10, ethylene oxide units) with a fatty acid ester mixture, in which the mixture of fatty acids used for the production contains 10 to 40 wt.-% C 18:1 Fatty acids and / or 25-75 wt.-% C 18:2 Fatty acids and / or 1-20 wt.-% C 18:3 Contains fatty acids.

[0097] In some embodiments, the fatty acid ester has an acid number (AV) of 0 to 10 mg KOH / g, for example 2 to 8 mg KOH / g. The measurement of the acid number can be carried out using DIN EN ISO 2114.

[0098] In some embodiments, the fatty acid ester has a hydroxyl value (HV) of 5-200 mg KOH / g, such as 100-190 mg KOH / g and 120-180 mg KOH / g. The hydroxyl value is the amount of milligrams (mg) of potassium hydroxide (KOH) that corresponds to the acetylated hydroxyl groups in one gram of test product under the specified test conditions. The measurement of the hydroxyl value can be determined using DIN EN ISO 4629-1:2016-12.

[0099] In some embodiments, the fatty acid ester has a pour point of 5 to -50°C, such as 0 to -40°C and -10 to -30°C. The pour point is the lowest temperature at which the oil still flows when cooled under specified conditions. Measurement of the pour point can be performed using DIN ISO 3016.

[0100] In some embodiments, the fatty acid ester has a dynamic viscosity of 50-1000 mPa·s, for example 70-700 mPa·s and 100-400 mPa·s. Dynamic viscosity is defined as the quotient of shear stress and velocity gradient. Measurement of dynamic viscosity can be carried out using DIN ISO 3219. For this purpose, a viscometer (e.g. Roto Visko 1 viscometer from Haake) or a rheometer (e.g. Modular Compact 302 from Anton Paar) can be used.

[0101] Rubber Additives The rubber composition according to the present invention comprises at least one rubber additive comprising a fatty acid ester.

[0102] In one embodiment, the rubber additive may consist of a fatty acid ester or comprise at least 50 wt.-%, preferably at least 70 wt.-%, in particular at least 90 wt.-% fatty acid ester.

[0103] In addition to the fatty acid ester, the rubber additive may also have further components. In a preferred embodiment, the rubber additive comprises a fatty acid ester and / or a fatty acid soap, in particular a fatty acid zinc soap and / or a fatty acid potassium soap.

[0104] The rubber additive of the present invention may be present in a blend, preferably comprising one or more solid carrier substances and one or more fatty acid esters, and optionally further components. Inorganic fillers (e.g. silica) or waxy substances (e.g. polyethylene wax) may preferably be used as carrier substances.

[0105] In a preferred variant, silica is used as the support material. Examples of commercially available silicas that can be used in the blends of the invention are Sipernat 22 and Sipernat 50 from Evonik.

[0106] In the blend, for example amides, amino alcohols and soaps can be used as further components. Some fatty acid esters according to the invention can also be present in the blend.

[0107] The weight ratio of carrier material to fatty acid ester in the blend is, for example, 10 / 90 to 90 / 10, more preferably 20 / 80 to 80 / 20 and especially preferably about 30 / 70 or 33 / 67.

[0108] The use of a blend makes the fatty acid ester easier to handle, especially if it is a liquid at room temperature.

[0109] Rubber The rubber composition according to the present invention comprises at least one rubber.

[0110] In a preferred embodiment, the rubber is a rubber that can be crosslinked by sulfur crosslinking.According to the invention, rubbers are used that are particularly suitable for the manufacture of tread compounds that can be used in the manufacture of tires.

[0111] The preferred rubbers are diene rubbers. Rubbers formed by polymerization or copolymerization of dienes and / or cycloalkenes and therefore having C=C double bonds either in the main chain or in side groups are called diene rubbers. The preferred diene rubbers are butadiene rubber, polyisoprene and styrene-butadiene rubber.

[0112] In a preferred embodiment, the rubber composition comprises at least one of styrene-butadiene rubber, natural rubber, polyisoprene and / or butadiene rubber and optionally functionalized forms thereof.

[0113] In a preferred embodiment, the rubber composition comprises at least one styrene-butadiene rubber (styrene-butadiene copolymer). It can be both a solution-polymerized styrene-butadiene rubber (SSBR) and an emulsion-polymerized styrene-butadiene rubber (ESBR), where a mixture of at least one SSBR and at least one ESBR can also be used. The terms "styrene-butadiene rubber" and "styrene-butadiene copolymer" are used synonymously in the context of the present invention. The styrene-butadiene copolymer used can be end-group modified with modifications and functionalizations and / or functionalized along the polymer chain. The modifications can be with hydroxy groups and / or ethoxy groups and / or epoxy groups and / or siloxane groups and / or amino groups and / or aminosiloxanes and / or carboxy groups and / or phthalocyanine groups and / or silane sulfide groups. However, further modifications known to those skilled in the art, also called functionalizations, are also considered. Metal atoms can also be constituents of such functionalizations.

[0114] Butadiene rubber (=BR, polybutadiene) can be of all types known to those skilled in the art. These include, inter alia, the so-called high cis and low cis types, where polybutadienes with a cis content of 90 wt.-% or more are called high cis types and polybutadienes with a cis content of less than 90 wt.-% are called low cis types. Low cis polybutadienes are for example Li-BR (lithium catalyzed butadiene rubber) with a cis content of 20 to 50 wt.-%.

[0115] The polybutadienes used can be end-group modified and / or functionalized along the polymer chain. In this respect, reference can be made to the possibilities disclosed above in connection with the modification and functionalization of styrene-butadiene rubber, optionally adapted to the requirements of BR as a rubber material.

[0116] According to a preferred embodiment, the rubber composition comprises at least one styrene-butadiene rubber, preferably in an amount of 40 to 100 phr, particularly preferably 70 to 90 phr.

[0117] Additionally, oil extended rubbers may also be added to the rubber compositions according to the invention. It is also common to "calibrate" the oil content with respect to the amount of oil extended rubber used, which may result in formulations having "rubber" amounts in excess of 100 phr, such as up to 200 phr, for example ranging from 40 or 70 to 140 or 150 phr. However, since the oil content is usually known, the oil extended rubber may be added such that the sum of the solid rubber components (see definition above) results in a total of 100 parts by weight of rubber being present.

[0118] In one embodiment, the rubber additive is used to reduce the amount of oil in the oil-extended rubber, in which case less oil is used in the rubber composition according to the invention than in a rubber composition containing an oil-extended rubber that does not contain the rubber additive.

[0119] According to a preferred embodiment, the rubber composition comprises at least one styrene-butadiene rubber functionalized (backbone functionalized) at the polymer chain end and / or along the polymer chain with at least one of the above-named groups, the functional groups being particularly preferably groups capable of bonding to silica, such as in particular hydroxy groups and / or ethoxy groups and / or epoxy groups and / or siloxane groups and / or aminosiloxane and / or carboxy groups and / or silane sulfide groups.

[0120] According to a preferred embodiment, the rubber composition comprises 5 to 95 phr, preferably 10 to 30 phr, of at least one butadiene rubber.

[0121] The rubber composition according to the invention may also comprise natural and / or synthetic polyisoprene. Here, both cis-1,4-polyisoprene and 3,4-polyisoprene may be used. The rubber composition preferably comprises cis-1,4-polyisoprene with a cis-1,4 content of more than 90 wt.-%. Natural rubber is a rubber with a high cis-1,4 content. The polyisoprene used may also be end-group modified and / or functionalized along the polymer chain. In this regard, reference may be made to the possibilities disclosed above in connection with the modification and functionalization of styrene-butadiene rubber, optionally adapted to the requirements of polyisoprene as a rubber material.

[0122] The named rubbers may also be included in the rubber composition in combination with one another.

[0123] In a preferred embodiment, the rubber composition comprises at least one styrene-butadiene rubber and at least one butadiene rubber, in particular 5 to 95 phr of butadiene rubber and 5 to 80 phr of styrene-butadiene rubber.

[0124] In a further preferred embodiment, the rubber composition comprises at least one styrene-butadiene rubber, at least one butadiene rubber and at least one natural rubber, in particular 5 to 80 phr of butadiene rubber, 5 to 80 phr of styrene-butadiene rubber and 5 to 60 phr of natural rubber.

[0125] In a preferred embodiment, the rubber composition comprises at least one liquid polymer (viscous liquid at room temperature), such as LIR (liquid polyisoprene), LBR (liquid polybutadiene) and L-SBR (liquid styrene-butadiene).

[0126] For example, Kurapren LIR30 and Kurapren LIR50 from Kuraray Co., Ltd. may be used as liquid polyisoprenes. For example, LBR-302, LBR-307, LBR-305, LBR-352 or LBR-361 from Kuraray Co., Ltd. may be used as liquid polybutadienes. L-SBR-820 or L-SBR-841 from Kuraray Co., Ltd. may be used as liquid styrene-butadiene.

[0127] The rubber composition according to the present invention may further comprise additional rubbers in relatively small amounts, for example, from 0.1 to 50 phr.

[0128] Further Additives The rubber composition of the present invention may contain further additives and components, in particular one or more fillers, one or more catalysts or activators for sulfur crosslinking and, if desired, further additives.

[0129] In a preferred embodiment, the rubber composition of the present invention contains further additives and components suitable for making tread compounds for tires.

[0130] The rubber composition preferably contains at least one filler. The rubber composition may contain 5 to 300 phr, preferably 30 to 300 phr, particularly 50 to 200 phr of at least one filler, which means the total amount of all fillers contained therein.

[0131] According to a preferred embodiment of the invention, the total filler content is between 30 and 150 phr, particularly preferably between 60 and 140 phr, again particularly preferably between 80 and 130 phr, again particularly preferably between 100 and 130 phr and again very particularly preferably between 110 and 130 phr.

[0132] These may be all fillers known to those skilled in the art, for example carbon black, carbon nanotubes, silica, aluminosilicates, phyllosilicates such as kaolin, calcium carbonate (chalk), starch, calcium carbonate, barium sulfate, magnesium oxide, aluminum oxide, titanium dioxide, or rubber gels.

[0133] The rubber composition preferably contains at least one silica as a filler. The silica may be any silica known to those skilled in the art to be suitable as a filler for rubber compositions. However, the preferred range is from 35 to 350 m. 2 / g, preferably 35 to 260 m 2 / g, particularly preferably 100 to 260 m 2 / g and very particularly preferably 115 to 235 m 2 / g nitrogen surface area (BET surface area) (according to DIN ISO 9277) and 30-400 m 2 / g, preferably 30 to 250 m 2 / g, particularly preferably 80 to 250 m 2 / g and very particularly preferably 80 to 230 m 2 It is particularly preferred when finely distributed precipitated silica is used, having a CTAB surface area (according to ASTM D 3765) of 100000 / g.

[0134] As silicas, for example, both silicas of the type Ultrasil® 7000 GR (trade name) from Evonik, as well as Ultrasil® VN3 (trade name) from Evonik, and also highly disperse silicas, so-called HD silicas (for example Zeosil® 1165 MP from Solvay) can therefore be used.

[0135] Silane coupling agents can be used in rubber compositions to improve processability and to bond silica and other polar fillers that may be present to the rubber. Here, one or more different silane coupling agents can be used in combination with each other. The rubber composition can therefore contain a mixture of different silanes. The silane coupling agent reacts with silanol groups or other polar groups on the surface of the silica during the mixing of the rubber or rubber composition (in situ) or before adding the filler to the rubber in the sense of pretreatment (premodification). All silane coupling agents known to those skilled in the art for use in rubber compositions can be used here as silane coupling agents. Such coupling agents known in the art are difunctional organosilanes, which have at least one alkoxy, cycloalkoxy or phenoxy group as a leaving group on the silicon atom and, as the other functionality, a group that can undergo a chemical reaction with the double bond of the polymer, if necessary after decomposition.

[0136] It is further advantageous if the rubber composition according to the invention comprises at least one plasticizer, where the total amount of plasticizer is preferably between 5 and 150 phr. Plasticizers used in the context of the present invention include all plasticizers known to those skilled in the art, such as aromatic, naphthenic or paraffinic mineral oil plasticizers, for example MES (light extractive solvates) or RAE (residual aromatic extracts) or TDAE (treated distillate aromatic extracts), or rubber-to-liquid (RTL) oils or biomass-to-liquid (BTL) oils, or oil rubbers, or plasticizer resins or natural oils (sunflower oil, rapeseed oil), preferably having a polyaromatic content of less than 3 wt.-% according to the IP 346 method. The rubber composition may comprise between 5 and 40 phr, preferably between 10 and 30 phr, of plasticizer.

[0137] In some embodiments, rubber additives are used to reduce the amount of plasticizer in the rubber composition or to replace plasticizer. In this case, less plasticizer is used in the rubber composition according to the present invention than in the rubber composition without rubber additives. This can be advantageous in certain cases, for example for environmental protection or economic reasons.

[0138] The rubber composition preferably further comprises substances required for crosslinking, such as zinc oxide, accelerators and / or sulfur.

[0139] It is particularly advantageous if the rubber composition according to the invention comprises zinc oxide or a zinc-containing compound for the activation of sulfur vulcanization. The vulcanization of the rubber composition can be carried out with a vulcanization accelerator in the presence of sulfur and / or sulfur donors, where some vulcanization accelerators can simultaneously act as sulfur donors, and the sulfur and / or sulfur donors and vulcanization accelerators are used in amounts known in the art. The sulfur and / or sulfur donors and one or more accelerators are added to the rubber composition in the final mixing step in the designated amounts. The accelerators are selected from the group consisting of thiazole accelerators and / or mercapto accelerators and / or sulfenamide accelerators and / or thiocarbamate accelerators and / or thiuram accelerators and / or thiophosphate accelerators and / or thiourea accelerators and / or xanthate accelerators and / or guanidine accelerators. Preference is given to using at least one sulfenamide accelerator selected from the group consisting of N-cyclohexyl-2-benzothiazole sulfenamide (CBS) and / or N,N-dicyclohexylbenzothiazole-2-sulfenamide (DCBS) and / or benzothiazyl-2-sulfenamide morpholide (MBS) and / or 2,2'-dibenzothiazyl disulfide (MBTS) and / or N-tert-butyl-2-benzothiazyl sulfenamide (TBBS).

[0140] Several accelerators may also be used. Sulfenamide accelerators, particularly preferably CBS, are preferably used in combination with the guanidine accelerator DPG (1,3-diphenylguanidine). The amount of DPG is 0-5 phr, preferably 0.1-3 phr, particularly preferably 0.5-2.5 phr, very particularly preferably 1-2.5 phr.

[0141] In addition, the rubber composition may contain conventional additives in conventional parts by weight, which may be selected from the list consisting of antioxidants, activators, waxes, resins, chewing aids and processing aids, and mixtures thereof.

[0142] Examples of the antioxidant that can be used include 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) and 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ). The rubber composition according to the present invention preferably contains 0.1 to 3 phr of the antioxidant.

[0143] As the activator, for example, zinc oxide and a fatty acid (e.g., stearic acid) or a zinc complex (e.g., zinc ethylhexanoate) can be used. The rubber composition according to the present invention preferably contains 0.5 to 10 phr, preferably 2 to 5 phr, of the activator.

[0144] The rubber composition according to the present invention preferably contains 0.1 to 3 phr of wax.

[0145] As resins, in particular, plasticizer resins such as C5 petroleum resins, C9 petroleum resins, terpene resins, coumarone-indene resins or hydrocarbon resins consisting of α-methylstyrene and styrene (AMS resins) can be used. The rubber composition according to the invention preferably contains 5 to 150 phr of resin, preferably 15 to 50 phr.

[0146] As the chewing aid, for example, 2,2'-dibenzamidodiphenyl disulfide (DBD) can be used. The rubber composition according to the present invention preferably contains 0.1 to 3 phr of the chewing aid.

[0147] For example, fatty acid salts such as zinc soap can be used as processing aids. The rubber composition according to the present invention preferably contains 0.5 to 10 phr, preferably 2 to 5 phr, of the processing aid.

[0148] In particular, the rubber composition a) 0.1 to 3 phr of an antioxidant; b) 0.5 to 10 phr, preferably 2 to 5 phr, of an activator; c) 0.1-3 phr of wax; d) 5 to 100 phr, preferably 15 to 50 phr, of resin; e) 0.1 to 3 phr of a chewing aid, and f) 0.5 to 10 phr, preferably 2 to 5 phr, of processing aids Includes.

[0149] The proportion of the further additives in the total amount is between 3 and 150 phr, preferably between 3 and 100 phr and particularly preferably between 5 and 80 phr.

[0150] composition The rubber composition preferably contains between 0.1 and 40 phr of fatty acid ester, for example 1-40, 2-40, 3-40, 4-40 or 5-40.

[0151] In a preferred embodiment, the rubber composition comprises from 1 to 30 phr of fatty acid ester, for example from 2 to 30, 3 to 30, 4 to 30, and especially from 5 to 30 phr.

[0152] For this reason, the fatty acid esters according to the invention can on the one hand be added (in addition to other plasticizers) to existing rubber compositions in so-called "on-top" applications. In such cases, use concentrations of 0.5 to 5 phr are preferred. The fatty acid esters according to the invention can also be used to completely or at least partially replace other plasticizers. In such cases, much higher use concentrations, in particular 5 to 40 phr or 5 to 30 phr, are advantageous.

[0153] In a preferred embodiment, after vulcanization the composition has at least 5%, preferably 10%, in particular 15% lower rolling resistance, tan δ at 60°C, and / or 5%, preferably 10%, in particular 15% higher wet grip, tan δ at 0°C.

[0154] Furthermore, the composition preferably has improved processability during extrusion, in particular at least a 5%, preferably 10%, in particular 15% lower Mooney viscosity and / or a correspondingly lower material pressure.

[0155] Furthermore, the composition preferably has improved stiffness, in particular at least 5%, preferably 10%, in particular 15% higher tear strength and / or elongation at break and / or tensile strength at 100% modulus and / or tensile strength at 300% modulus.

[0156] The above mentioned improvements (low rolling resistance, high wet grip, improved processability, increased stiffness) can be determined by comparison with an identical composition which contains, instead of the additive according to the invention, the same amount of a rubber additive known from the prior art. For the test, two otherwise identical rubber compositions are prepared and their properties are then compared with each other.

[0157] Moreover, the above improvements (low rolling resistance, high wet grip, improved processability, increased stiffness) can be determined by comparison with an otherwise identical composition containing the same amount of a rubber additive known from the prior art instead of the additive according to the invention. For example, a commercially available material such as Tudalen 4192 can be used as the known plasticizer. For the test, two otherwise identical rubber compositions are produced and then their properties are compared with each other.

[0158] The above improvements can also be determined by comparison with an otherwise identical composition that does not contain the rubber additive according to the invention. In this case, for testing, two identical rubber compositions are prepared, one of which additionally contains the rubber additive according to the invention. The properties of the two rubber compositions are then compared with each other.

[0159] The rubber composition is preferably suitable for the manufacture of tread compounds for tires. The rubber composition according to the invention is also suitable for treads consisting of different tread compounds arranged next to each other and / or one above the other (multicomponent treads).

[0160] manufacturing The rubber additives defined above are usually prepared by simply mixing the components. This is done until the desired homogeneous mixture is achieved. Suitable mixing equipment is known to those skilled in the art.

[0161] The preparation of the rubber composition according to the invention is carried out in a conventional manner, whereby a basic mixture containing all the components except the vulcanization system (sulphur and substances influencing the vulcanization) is first prepared in one or more mixing steps, and the finished mixture is subsequently prepared by adding the vulcanization system.

[0162] The composition can then be further processed, for example by an extrusion process, and brought into a corresponding form, for example in the form of a tread blank.

[0163] Typical processes for producing rubber compositions and vulcanizates thereof are described in the "Handbook of Rubber Technology", W. Hofmann, Hanser Verlag 1994. It is known to those skilled in the art that, if necessary depending on the mixture, in particular the filler content, further mixing steps are carried out after the first basic mixing step in order to achieve a better reduction in viscosity and a better homogenization.

[0164] tire The present invention also relates to a tire, at least one component of which is at least partially made from the rubber composition according to the invention. The tire is preferably an all-season tire or a winter tire.

[0165] In the context of the present invention, tyres refers to pneumatic vehicle tyres and solid rubber tyres, including tyres for industrial and construction site vehicles, HGVs, passenger cars and motorcycles.

[0166] According to a preferred embodiment of the invention, the tire comprises at least in its tread a rubber composition according to the invention.

[0167] The present invention further relates to a process for producing a tire, one or more components of which are produced from a rubber composition according to the invention, and the rubber composition is cured.

[0168] The use of the rubber composition according to the invention can significantly improve the processes for manufacturing tires and treads.

[0169] use The present invention further relates to a rubber additive in a rubber composition for improving the Mooney viscosity and / or extrusion properties of the rubber composition, and / or for improving at least one of the wear, wet grip and / or rolling resistance of a tire made from the rubber composition. 22 The present invention relates to the use of fatty acid esters of fatty acids with compounds selected from C2-C4 alkoxylates of polyols, polyethylene glycols, polypropylene glycols and / or copolymers of ethylene oxide and propylene oxide.

[0170] In a preferred embodiment of the use according to the invention, at least one of the named properties is improved compared to a composition that contains the same amount of a known rubber additive instead of the rubber additive according to the invention.Substances known in the art to be used as rubber additives can be used as known rubber additives.For the test, two otherwise identical rubber compositions are prepared and then their properties are compared with each other.

[0171] In a preferred embodiment, at least one of the named properties is improved by at least 5%, preferably at least 10%, compared to a rubber composition containing the same amount of a known rubber additive instead of the rubber additive according to the invention.

[0172] In a preferred embodiment, at least one of the named properties is improved by at least 5%, preferably at least 10%, compared to an otherwise identical rubber composition, i.e., to which the rubber additive according to the present invention has been further added. In this case, for the test, two identical rubber compositions are prepared and to one of them the rubber additive according to the invention is additionally added. The properties of the two rubber compositions are then compared with each other.

[0173] In a preferred embodiment, at least one of the named properties is improved by at least 5%, preferably at least 10%, compared to a rubber composition that contains the same amount of a known plasticizer instead of the rubber additive according to the invention and is otherwise identical. Commercially available materials, such as Tudalen 4192, can be used as the known plasticizer.

[0174] In a preferred embodiment, the extrusion properties of the rubber composition are improved compared to a rubber composition which contains the same amount of a known plasticizer instead of the rubber additive according to the invention or which does not contain a plasticizer and is otherwise identical. By extrusion properties is meant properties such as extrusion speed, die swell, extrusion rate, material pressure, material temperature and / or surface / edge condition of the extrudate.

[0175] In a preferred embodiment, the surface and / or edge condition of the extrudate is improved, where the surface is rated using a grading system of A to E, with A representing the best grade, and the edges are rated using a grading system of 1 to 10, with 10 representing the best grade (in both cases according to ASTM D 2230).

[0176] The rubber additive according to the invention may be used in particular in rubber compositions for treads.

[0177] In a preferred embodiment, in the use according to the invention, a) one or more solid support materials, and b) one or more fatty acid esters, and c) Optionally further components such as amides, amino alcohols and / or soaps A blend including the following is used.

[0178] Inorganic fillers (e.g. silica) or waxy substances (e.g. polyethylene wax) may preferably be used as the support material. In a preferred embodiment, silica is used as the support material.

[0179] The weight ratio of carrier material to fatty acid ester in the blend is, for example, 10 / 90 to 90 / 10, more preferably 20 / 80 to 80 / 20 and especially preferably about 30 / 70 or 33 / 67.

[0180] Working Example The present invention will be described in more detail below with reference to comparative examples and examples, but the present invention is not limited to these examples.

[0181] Example 1 - Preparation of a rubber additive according to the invention a) Rubber Additive A 1217.8 g ethoxylated glycerol (Aduxol GLY-07 from Schaerer + Schlaepfer), 835.7 g fatty acids and 2.0 g hypophosphorous acid were fed. 18:1 , 8% C 18:2 , 6% C 16:1 , 4.5% C 16 , 4% C 14+14:1 , C≦4% 14 , C≦3% 18 , C≦2.5% 18:3 and C ≤ 1% 12The oleic acid mixture was used as fatty acid. The oleic acid mixture had an acid value of 201.0 mg KOH / g, a saponification value of 202.0 mg KOH / g and an iodine value of 100.0 g iodine / 100 g. The iodine value was determined according to DIN EN ISO 3961 2018-11 and the saponification value was determined according to DIN EN ISO 3681.

[0182] The mixture was slowly heated to 230° C. and a vacuum was applied. The progress of the reaction was monitored by measuring the acid number. The fatty acid ester formed had an acid number of 4.6 mg KOH / g. From the hydroxyl number measurement it was possible to deduce that mainly monoesters were obtained.

[0183] b) Rubber Additive B 592.2 g of polyethylene glycol 400, 408.7 g of fatty acid, and 1.0 g of hypophosphorous acid were fed. 18 , 20-29% C 18:1 , 47-58% C 18:2 , 4~10% C 18:3 , 9-12% C 16 , 0~1% C 16:1 and 0-1% C 12+14 Distilled soybean oil fatty acids containing 1,2-dichlorophenyl ether were used as fatty acids. The soybean oil fatty acids used had an acid value of 194-204 mg KOH / g, a saponification value of 195-206 mg KOH / g, and an iodine value of 125-139 g iodine / 100 g.

[0184] The mixture was slowly heated to 230°C and a vacuum was applied. The progress of the reaction was monitored by measuring the acid number. The fatty acid ester produced had an acid number of 1.9 mg KOH / g. The dynamic viscosity of the fatty acid ester produced at 20°C was 95.1 mmHg. 2 / sec, and the dynamic viscosity at 20°C was 94.8 mPa·s.

[0185] c) Rubber Additive C 352.8 g of polypropylene glycol 600, 161.8 g of soybean oil fatty acid (see rubber additive B) and 0.5 g of hypophosphorous acid were fed.

[0186] The mixture was slowly heated to 230°C and a vacuum was applied. The progress of the reaction was monitored by measuring the acid number. The fatty acid ester produced had an acid number of 1.7 mg KOH / g. The dynamic viscosity of the fatty acid ester produced at 20°C was 107.1 mmHg. 2 / sec.

[0187] Example 2 - Preparation of a rubber composition according to the invention The mixture is produced under normal conditions in one or more mixing steps, which is then further processed, for example by an extrusion process, and brought into the corresponding form.

[0188] The different components of the individual mixtures are shown in the table provided below.

[0189] [Table 1]

[0190] In all mixing examples contained in the tables, the amounts (parts by weight) given are based on 100 parts by weight of total rubber (phr).

[0191] Test specimens were prepared from all the mixtures and the following test methods were used to determine the material properties typical for the rubber industry: Mooney viscosity (MS 1+4, 100 °C), after each mixing step and after ageing, in each case according to DIN EN ISO 289-1, Extrusion characteristics (extrusion speed, die swell, extrusion rate, material pressure, material temperature) Surface evaluation (Garvey die: surface A-E, A being the best grade, edge 1-10, 10 being the best grade), in each case according to ASTM D 2230; The material pressure at different shear rates was measured using a Goettfert high pressure capillary Rheograph 25 (measurement temperature 100 °C, nozzle shape: circular, length 10 mm, diameter 1 mm). Rebound resilience at RT, measured according to ASTM D-8059 Shore A hardness at room temperature (RT), measured according to DIN EN ISO 868 Tear strength, elongation at break and tensile strength measured according to DIN 53 504, parameters for stiffness and for tire wear, Stress values ​​at 100 and 300% elongation (100% modulus, 300% modulus) at room temperature, according to DIN 53 504, Loss factor -tan δ at 20°C, 0°C and 60°C, according to DIN 53 545, Dynamic Mechanical Analysis, where the vulcanized material is clamped and dynamically loaded; As described in Encyclopedia of Polymer Blends, Volume 2: Processing, edited by Avraam I. Isayev and Sanjay Palsule, grip on snow can be correlated with tan δ at -20°C (the higher the tan δ at -20°C, the better the snow grip). Wet grip can be correlated with tan δ at 0°C (the higher the tan δ at 0°C, the better the wet grip). o Rolling resistance can be correlated with tan δ at 60°C (the smaller the tan δ at 60°C, the lower the rolling resistance). Rebound according to DIN 53512.

[0192] Example 3 - Comparison with processing oil In this example, the properties of the rubber composition containing additive A (composition B) prepared in Example 1 are compared with the properties of an otherwise identical rubber composition (composition A) containing only TDAE oil. The comparison shows the improved processing properties of rubber composition B according to the invention as well as improved tire handling and comparable tire grip properties. Furthermore, the rubber composition according to the invention has a particularly low rolling resistance, tan δ at 60° C.

[0193] The corresponding information and data are shown in Table 2 below.

[0194] [Table 2]

[0195] Images of different extrudates of compositions A and B (after 24 h and 1 week at 60 1 / min and 15 1 / min) are shown in Figure 1a-d, where Figure 1a shows the extrudate of compositions A and B after 24 h at 15 1 / min, Figure 1b shows the extrudate of compositions A and B after 24 h at 60 1 / min, Figure 1c shows the extrudate of compositions A and B after 1 week at 15 1 / min, and Figure 1d shows the extrudate of compositions A and B after 1 week at 60 1 / min.

[0196] As explained, the extrudates of rubber composition B according to the invention have in all cases much fewer edges and have an improved surface structure. Furthermore, rubber composition B according to the invention has good processability (low Mooney viscosity) and improved rolling resistance (low tan δ at 60° C.).

[0197] Example 4 - Comparison with a composition according to the invention without rubber additives This example compares the properties of a rubber composition having Additive A from Example 1 (Composition D) with the properties of an otherwise identical rubber composition without the additive (Composition C).

[0198] [Table 3]

[0199] Images of different extrudates of compositions C and D after 24 h at 60 1 / min and 15 1 / min are shown in Figures 2a and b, where Figure 2a shows the extrudate at 15 1 / min and Figure 2b shows the extrudate at 60 1 / min.

[0200] As explained, the extrudates of rubber composition D according to the invention have an improved surface structure in both cases. Furthermore, rubber composition D according to the invention has better processability (lower Mooney viscosity), improved tire handling (higher stiffness), better wear properties (improved ultimate tear properties and lower DIN abrasion values) and improved wet grip (higher tan δ at 0° C.) with comparable rolling resistance (tan δ at 60° C.).

[0201] Example 5 - Comparison with glycerol monooleate In this example, the properties of a rubber composition containing Additive A prepared in Example 1 (Composition E) were compared with the properties of an identical rubber composition containing glycerol monooleate instead (Composition F).

[0202] The comparison shows the improved processing properties of the rubber composition E according to the invention as well as improved tire handling and comparable to improved tire grip properties. Furthermore, the rubber composition according to the invention has a particularly low rolling resistance, tan δ at 60° C.

[0203] The corresponding information and data are shown in Table 4 below.

[0204] [Table 4]

[0205] Images of different extrudates of compositions E and F (after 24 h and 1 week at 60 1 / min and 15 1 / min) are shown in Figure 3a-d, where Figure 3a shows the extrudate of compositions E and F after 24 h at 15 1 / min, Figure 3b shows the extrudate of compositions E and F after 24 h at 60 1 / min, Figure 3c shows the extrudate of compositions E and F after 1 week at 15 1 / min, and Figure 3d shows the extrudate of compositions E and F after 1 week at 60 1 / min.

[0206] As can be seen from Figures 3a-d, the extrudates of rubber composition B according to the invention have in all cases much fewer edges and have an improved surface structure. Furthermore, rubber composition E according to the invention has improved tire handling (high stiffness), improved snow grip (high tan δ at -20°C), improved wet grip (high tan δ at 0°C) as well as improved rolling resistance (low tan δ at 60°C).

[0207] Example 6 - Comparison of properties of rubber additives A to C In this example, the properties of the rubber compositions containing additives A to C produced in Example 1 (compositions H to J) were compared with the properties of an identical rubber composition (composition G) except that it contained more TDAE processing oil instead.

[0208] The comparison (see data in Table 5) shows improved processing properties. Depending on the additives used, processing can be improved in a targeted manner at different process steps (e.g. during mixing or extrusion). Furthermore, through the selection of additives, further material properties can also be optimized in a target-directed manner.

[0209] [Table 5]

[0210] In general, compositions HJ according to the invention have improved extrusion properties (lower material pressure, improved extrudate) and lower mix viscosities.

[0211] Additive C (Composition J) has improved processability (low Mooney MS value and material pressure) as well as good final tear properties (tear strength, elongation at break and tear propagation strength) as indicators of good C&C (cutting and machining) properties and high tan δ values ​​at 0°C and 20°C as indicators of good tire grip in wet and dry conditions.

[0212] Additive B (composition I) shows a further clear improvement in processability, especially evident through lower material pressure at high shear rates, and at the same time has improved tear propagation strength without adversely affecting the conflicting goals of wet braking (equivalent tan δ at 0°C) - rolling resistance (equivalent tan δ at 60°C).

Claims

1. A rubber composition comprising rubber and at least one rubber additive, wherein the at least one rubber additive comprises a fatty acid ester, and the fatty acid ester comprises at least one C 8 ~C 22 C fatty acids and polyols 2 ~C 4 A rubber composition characterized by being produced from an alkoxylate, polyethylene glycol, polypropylene glycol, and / or at least one compound selected from copolymers of ethylene oxide and propylene oxide.

2. The fatty acid has at least one saturated or unsaturated C 12 -C 22 fatty acid, preferably at least one C 16 -C 20 fatty acid or a mixture thereof, particularly at least one C 18:1 fatty acid and / or C 18:2 The rubber composition according to claim 1, characterized by containing a fatty acid.

3. The rubber composition according to claim 1, characterized in that the fatty acid ester is produced from at least one polyethylene glycol, polypropylene glycol, and / or a statistical copolymer or block copolymer of ethylene oxide and propylene oxide, wherein the statistical copolymer or block copolymer of polyethylene glycol, polypropylene glycol, and / or ethylene oxide and propylene oxide preferably has a molecular weight of 200 to 800 g / mol.

4. The rubber composition according to claim 1, characterized in that the fatty acid ester is produced from at least one polyol ethoxylate having up to 10 such as 5 to 10 ethylene oxide units (EO units), for example 7 units, and / or at least one polyol propoxylate having up to 10 such as 5 to 10 propylene oxide units (PO units), for example 7 units, wherein the polyol ethoxylate or polyol propoxylate preferably has between 2 and 4 hydroxyl groups.

5. The rubber composition according to claim 4, characterized in that the polyol ethoxylate is ethoxylated glycerol having up to 10 ethylene oxide units (EO units), such as 7 units, particularly 5 to 10.

6. Fatty acid esters: • Acid value (AV) of 0–10 mg KOH / g; and / or • Hydroxyl value (HV) of 5–190 mg KOH / g; and / or • Freezing point of 5 to -50°C; and / or Dynamic viscosity of 50–1000 mPa·s The rubber composition according to claim 1, characterized by having the following:

7. The rubber composition according to claim 1, characterized by containing 0.1 to 40 phr, preferably 1 to 30 phr, and particularly 5 to 30 phr of fatty acid esters.

8. The rubber composition according to claim 1, characterized by comprising at least one styrene-butadiene rubber, polyisoprene rubber, natural rubber and / or butadiene rubber, and optionally functionalized forms thereof.

9. The rubber composition according to claim 1, characterized in that, compared to the same composition comprising the same amount of a known rubber additive instead of the rubber additive according to the present invention, it has at least 5%, preferably 10%, a Mooney viscosity and / or at least 5%, preferably 10%, a material pressure during extrusion.

10. The rubber composition according to claim 1, characterized in that, compared to the same composition containing the same amount of a known rubber additive instead of the rubber additive according to the present invention, it has at least 5%, preferably 10%, lower rolling resistance, tanδ at 60°C, and / or 5%, preferably 10%, particularly 15%, higher wet grip, tanδ at 0°C after vulcanization.

11. The rubber composition according to claim 1, characterized in that it is suitable for the manufacture of tread compounds for tires.

12. At least one C as a rubber additive in a rubber composition for improving the Mooney viscosity and / or extrusion properties of the rubber composition, and / or for improving at least one of wear, wet grip, and / or rolling resistance of a tire manufactured from the rubber composition. 8 ~C 22 C fatty acids and polyols 2 ~C 4 Use of fatty acid esters with alkoxylates, polyethylene glycol, polypropylene glycol, and / or copolymers of ethylene oxide and propylene oxide.

13. The use according to claim 12, wherein at least one of the designated properties is improved by at least 5%, preferably at least 10%, compared to the same composition containing the same amount of a known rubber additive instead of the rubber additive according to the present invention.

14. The use according to claim 12 or 13, characterized in that the fatty acid ester is as defined in claim 1 to 6, and / or the rubber composition is as defined in claim 7 to 11.

15. a) One or more solid support materials, where silica is preferably used as the support material. b) One or more fatty acid esters and c) Further ingredients as needed, such as amides, amino alcohols and / or soaps. The use according to claim 12, characterized in that a blend containing is used.

16. A process for manufacturing a tire, characterized in that one or more components of the tire are manufactured from a rubber composition described in one of claims 1 to 11, and the rubber composition is cured.

17. A tire in which at least one component is manufactured at least partially from a rubber composition according to claim 1 to 11, preferably an all-season tire or a winter tire, wherein the component is in particular a tread.

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