Patent Application
20210292514
The invention relates to thioether silanes, to processes for preparation thereof and to the use thereof.
CAS 93575-00-9 discloses a compound of the formula
In addition, WO 2005059022 A1 and WO 2007039416 A1 disclose silanes of the formula
and the use thereof in rubber mixtures.
Chem. Commun. 2011, 47, 11113-11115 discloses a silane of the formula
and DE 2340886 A1 a silane of the formula
In addition, JP 2008310044 A discloses silanes of the formula
and the use thereof in microlenses.
Disadvantages of the known silanes are inadequate abrasion resistance and low dynamic stiffness in rubber mixtures.
The problem addressed by the present invention is that of providing thioether silanes that have advantages in abrasion resistance and dynamic stiffness over the silanes known from the prior art in rubber mixtures.
The invention provides a thioether silane of the formula I
(R1)x(R2)3-xSi—R3—S—C(CH2R)y(R5)3-y (I)
where R1 is the same or different and is C1-C10-alkoxy groups, preferably ethoxy, phenoxy groups, C4-C10-cycloalkoxy groups or alkyl polyether groups —O—(R6—O)rR7 where R6 is the same or different and is a branched or unbranched, saturated or unsaturated, aliphatic, aromatic or mixed aliphatic/aromatic divalent C1-C30 hydrocarbon group, r is an integer from 1 to 30 and R7 is an unsubstituted or substituted, branched or unbranched, monovalent alkyl, alkenyl, aryl or aralkyl group,
R2 is the same or different and is C6-C20-aryl groups, C1-C10-alkyl groups, C2-C20-alkenyl groups, C7-C20-aralkyl groups or halogen,
R3 is a branched or unbranched, saturated or unsaturated, aliphatic, aromatic or mixed aliphatic/aromatic divalent C1-C30 hydrocarbon group,
R4 is the same or different and is H, branched or unbranched, saturated or unsaturated, aliphatic C1-C30 hydrocarbon groups,
R5 is the same or different and is unsubstituted C6-C20-aryl groups, alkyl-substituted C6-C20-aryl groups or —C≡C—R8 groups, preferably unsubstituted C6-C20-aryl groups, more preferably phenyl groups, where R8 is H, an unsubstituted or substituted, branched or unbranched monovalent alkyl group or a C6-C20-aryl group, and x=1, 2 or 3, preferably 3, y=1 or 2, preferably 2.
Thioether silanes may be mixtures of thioether silanes of the formula I.
The inventive thioether silane of the formula I may contain oligomers, preferably dimers, that form through hydrolysis and condensation of the alkoxysilane functions of the thioether silanes of the formula I.
The inventive thioether silane of the formula I may contain isomers that form through a different regioselectivity in the preparation of the thioether silanes of the formula I.
The thioether silanes of the formula I may have been applied to a support, for example wax, polymer or carbon black. The thioether silanes of the formula I may have been applied to a silica, in which case the binding may be physical or chemical.
R3 may preferably be —CH2—, —CH2CH2—, —CH2CH2CH2—, —CH2CH2CH2CH2—, —CH(CH3)—, —CH2CH(CH3)—, —CH(CH3)CH2—, —C(CH3)2—, —CH(C2H5)—, —CH2CH2CH(CH3)—, —CH(CH3)CH2CH2—, —CH2CH(CH3)CH2—, —CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2—, —CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2— or
R1 may preferably be methoxy or ethoxy, more preferably ethoxy.
R4 may preferably be H, methyl or ethyl, more preferably H.
R5 may preferably be phenyl, naphthyl or tolyl, more preferably phenyl.
Thioether silanes of the formula I may preferably be compounds with R1 ethoxy, R4 H, and R5 phenyl or tolyl.
Thioether silane of the formula I may more preferably be compounds with R1 ethoxy, x=3, R3 CH2CH2CH2, R4 H, and R5 phenyl.
Thioether silanes of the formula I may preferably be:
(EtO)3Si—CH2—S—C(CH3)2(phenyl),
(EtO)3Si—CH2CH2—S—C(CH3)2(phenyl),
(EtO)3Si—CH2CH2CH2—S—C(CH3)2(phenyl),
(EtO)3Si—CH2—S—C(CH3)(phenyl)2,
(EtO)3Si—CH2CH2—S—C(CH3)(phenyl)2,
(EtO)3Si—CH2CH2CH2—S—C(CH3)(phenyl)2,
(EtO)3Si—CH2—S—C(CH3)2(naphthyl),
(EtO)3Si—CH2CH2—S—C(CH3)2(naphthyl),
(EtO)3Si—CH2CH2CH2—S—C(CH3)2(naphthyl),
(EtO)3Si—CH2—S—C(CH3)(naphthyl)2,
(EtO)3Si—CH2CH2—S—C(CH3)(naphthyl)2,
(EtO)3Si—CH2CH2CH2≥S≥C(CH3)(naphthyl)2,
(EtO)3Si—CH2—S—C(CH3)2(tolyl),
(EtO)3Si—CH2CH2—S—C(CH3)2(tolyl),
(EtO)3Si—CH2CH2CH2—S—C(CH3)2(tolyl),
(EtO)3Si—CH2—S—C(CH3)(tolyl)2,
(EtO)3Si—CH2CH2—S—C(CH3)(tolyl)2,
(EtO)3Si—CH2CH2CH2—S—CH3)(tolyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)2(phenyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)2(phenyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2−S—C(CH3)2(phenyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)(phenyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)(phenyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2—S—C(CH3)(phenyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)2(naphthyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)2(naphthyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2—S—C(CH3)2(naphthyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)(naphthyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)(naphthyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2—S—C(CH3)(naphthyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)2(tolyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)2(tolyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2—S—C(CH3)2(tolyl),
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2—S—C(CH3)(tolyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2—S—C(CH3)(tolyl)2,
(H27C13—(O—C2H4)5—O)(EtO)2Si—CH2CH2CH2—S—C(CH3)(tolyl)2,
(MeO)3Si—CH2—S—C(CH3)2(phenyl),
(MeO)3Si—CH2CH2—S—C(CH3)2(phenyl),
(MeO)3Si—CH2CH2CH2—S—C(CH3)2(phenyl),
(MeO)3Si—CH2—S—C(CH3)(phenyl)2,
(MeO)3Si—CH2CH2—S—C(CH3)(phenyl)2,
(MeO)3Si—CH2CH2CH2—S—C(CH3)(phenyl)2,
(MeO)3Si—CH2—S—C(CH3)2(naphthyl),
(MeO)3Si—CH2CH2—S—C(CH3)2(naphthyl),
(MeO)3Si—CH2CH2CH2—S—C(CH3)2(naphthyl),
(MeO)3Si—CH2—S—C(CH3)(naphthyl)2,
(MeO)3Si—CH2CH2—S—C(CH3)(naphthyl)2,
(MeO)3Si—CH2CH2CH2—S—C(CH3)(naphthyl)2,
(MeO)3Si—CH2—S—C(CH3)2(tolyl),
(MeO)3Si—CH2CH2—S—C(CH3)2(tolyl),
(MeO)3Si—CH2CH2CH2—S—C(CH3)2(tolyl),
(MeO)3Si—CH2—S—C(CH3)(tolyl)2,
(MeO)3Si—CH2CH2—S—C(CH3)(tolyl)2,
(MeO)3Si—CH2CH2CH2—S—C(CH3)(tolyl)2,
(EtO)3Si—CH2—S—C(CH3)2C≡CH,
(EtO)3Si—CH2CH2—S—C(CH3)2C≡CH,
(EtO)3Si—CH2CH2CH2—S—C(CH3)2C≡CH,
(EtO)3Si—CH2—S—C(CH3)2C≡C—CH2CH3,
(EtO)3Si—CH2CH2—S—C(CH3)2C≡C—CH2CH3,
(EtO)3Si—CH2CH2CH2—S—C(CH3)2C≡C—CH2CH3,
(EtO)3Si—CH2—S—C(CH3)2C≡C—CH3,
(EtO)3Si—CH2CH2—S—C(CH3)2C≡C—CH3,
(EtO)3Si—CH2CH2CH2—S—C(CH3)2C≡C—CH3,
(EtO)3Si—CH2—S—C(CH3)2C≡C-Ph,
(EtO)3Si—CH2CH2—S—C(CH3)2C≡C-Ph,
(EtO)3Si—CH2CH2CH2—S—C(CH3)2C≡C-Ph,
(MeO)3Si—CH2—S—C(CH3)2C≡CH,
(MeO)3Si—CH2CH2—S—C(CH3)2C≡CH,
(MeO)3Si—CH2CH2CH2—S—C(CH3)2C≡CH,
(MeO)3Si—CH2—S—C(CH3)2C≡C—CH2CH3,
(MeO)3Si—CH2CH2—S—C(CH3)2C≡C—CH2CH3,
(MeO)3Si—CH2CH2CH2—S—C(CH3)2C≡C—CH2CH3,
(MeO)3Si—CH2—S—C(CH3)2C≡C—CH3,
(MeO)3Si—CH2CH2—S—C(CH3)2C≡C—CH3,
(MeO)3Si—CH2CH2CH2—S—C(CH3)2C≡C—CH3,
(MeO)3Si—CH2—S—C(CH3)2C≡C-Ph,
(MeO)3Si—CH2CH2—S—C(CH3)2C≡C-Ph,
(MeO)3Si—CH2CH2CH2—S—C(CH3)2C≡C-Ph.
Especially preferred compounds are those of the formula (EtO)3Si—CH2CH2CH2—S—C(CH3)2(phenyl) and (EtO)3Si—CH2CH2CH2—S—C(CH3)(phenyl)2.
The invention further provides a process for preparing the inventive thioether silanes of the formula I
(R1)x(R2)3-xSi—R3—S—C(CH2R4)y(R5)3-y (I)
where R1, R2, R3, R4, R5, x and y have the definition given above, which is characterized in that a silane of the formula II
(R1)x(R2)3-xSi—R3—SH (II)
is reacted with an alkene of the formula III
R4—HC═C(CH2R4)y-1(R5)3-y (III).
Silanes of the formula II may preferably be:
(C2H5O)3Si—CH2—SH,
(C2H5O)3Si—CH2CH2—SH,
(C2H5O)3Si—CH2CH2CH2—SH,
(H27C13—(O—C2H4)5—O)(C2H5O)2Si—CH2—SH,
(H27C13—(O—C2H4)5—O)(C2H5O)2Si—CH2CH2—SH,
(H27C13—(O—C2H4)5-O)(C2H5O)2Si—CH2CH2CH2—SH,
(CH3O)3Si—CH2—SH,
(CH3O)3Si—CH2CH2—SH or
(CH3O)3Si—CH2CH2CH2—SH.
Compounds of the formula III may preferably be:
H2C═C(Me)(phenyl),
H2C═C(Me)(naphthyl),
H2C═C(Me)(tolyl),
H2C═C(phenyl)(phenyl),
H2C═C(naphthyl)(naphthyl),
H2C═C(tolyl)(tolyl),
H2C═C(Me)C≡CH,
H2C═C(Me)C≡C≡CH3,
H2C═C(Me)C≡C≡CH2CH3 or
H2C═C(Me)C≡C(phenyl).
The reaction can be conducted with exclusion of air.
The reaction may be carried out under a protective gas atmosphere, for example under argon or nitrogen, preferably under nitrogen.
The process according to the invention can be conducted at standard pressure, elevated pressure or reduced pressure. Preferably, the process according to the invention can be conducted at standard pressure.
Elevated pressure may be a pressure of 1.1 bar to 100 bar, preferably of 1.1 bar to 50 bar, more preferably of 1.1 bar to 20 bar and very preferably of 1.1 to 10 bar.
Reduced pressure may be a pressure of 1 mbar to 1000 mbar, preferably 1 mbar to 500 mbar, more preferably 1 mbar to 250 mbar, very preferably 1 mbar to 100 mbar.
The process according to the invention can be conducted between 20° C. and 180° C., preferably between 60° C. and 140° C., more preferably between 70° C. and 110° C.
The reaction can be effected in a solvent, for example methanol, ethanol, propanol, butanol, cyclohexanol, N,N-dimethylformamide, dimethyl sulfoxide, pentane, hexane, cyclohexane, heptane, octane, decane, toluene, xylene, acetone, acetonitrile, diethyl ether, methyl tert-butyl ether, methyl ethyl ketone, tetrahydrofuran, dioxane, pyridine or ethyl acetate.
The reaction can preferably be conducted without a solvent.
The reaction may be conducted in a catalysed manner. Catalysts used may be BF3, SO3, SnCl4, TiCl4, SiCl4, ZnCl2, FeCl3 or AlCl3.
It is possible with preference to use FeCl3, AlCl3 or ZnCl2.
It is possible with particular preference to use AlCl3.
The co-reactants may all be initially charged together or metered into one another. Preferably, the compound of the formula III may be added to the silane of the formula II.
The process according to the invention can give rise to by-products, for example dimers of the thioether silanes of the formula I, dimers of the alkenes of the formula III and reaction product of the silane of the formula II with the R1 substituent to form a thioether.
The thioether silanes of the formula I may be used as adhesion promoters between inorganic materials, for example glass beads, glass fragments, glass surfaces, glass fibres, or oxidic fillers, preferably silicas such as precipitated silicas and formed silicas, and organic polymers, for example thermosets, thermoplastics or elastomers, or as crosslinking agents and surface modifiers for oxidic surfaces.
The thioether silanes of the formula I may be used as coupling reagents in filled rubber mixtures, examples being tyre treads, industrial rubber articles or footwear soles.
The invention further provides rubber mixtures which are characterized in that they comprise at least one rubber and at least one thioether silane of the formula I.
The rubber mixture according to the invention may comprise a mercaptosilane. The mercaptosilane may be mercaptopropyltriethoxysilane, for example VP Si 263 from Evonik Resource Efficiency GmbH, blocked mercaptosilane, preferably 3-octanoylthio-1-propyltriethoxysilane, for example NXT™ from Momentive Performance Materials Inc., or transesterified mercaptopropyltriethoxysilane, preferably 4-((3,6,9,12,15-pentaoxaoctacosyl)oxy)-4-ethoxy-5,8,11,14,17,20-hexaoxa-4-silatritriacontane-1-thiol, for example Si 363™ from Evonik Resource Efficiency GmbH.
The rubber mixture may comprise at least one filler.
Fillers usable for the rubber mixtures according to the invention include the following fillers:
It is possible with preference to use amorphous silicas, more preferably precipitated silicas or silicates, especially preferably precipitated silicas having a BET surface area of 20 to 400 m2/g in amounts of 5 to 180 parts by weight in each case based on 100 parts of rubber.
The fillers mentioned may be used alone or in a mixture. In a particularly preferred embodiment of the process, it is possible to use 10 to 180 parts by weight of fillers, preferably precipitated silica, optionally together with 0 to 100 parts by weight of carbon black, and 0.1 to 20 parts by weight of thioether silane of the general formula I, based in each case on 100 parts by weight of rubber, to produce the mixtures.
Synthetic rubbers as well as natural rubber are suitable for producing the rubber mixtures according to the invention. Preferred synthetic rubbers are described for example in W. Hofmann, Kautschuktechnologie [Rubber Technology], Genter Verlag, Stuttgart 1980. These include
The rubber used may more preferably be NR or functionalized or unfunctionalized S-SBR/BR.
The rubber mixtures according to the invention may comprise further rubber auxiliaries, such as reaction accelerators, ageing stabilizers, heat stabilizers, light stabilizers, antiozonants, processing aids, plasticizers, resins, tackifiers, blowing agents, dyes, pigments, waxes, extenders, organic acids, retarders, metal oxides, and activators such as diphenylguanidine, triethanolamine, polyethylene glycol, alkoxy-terminated polyethylene glycol alkyl-O—(CH2—CH2—O)yI—H with yI=2-25, preferably yI=2-15, more preferably yI=3-10, most preferably yI=3-6, or hexanetriol, that are familiar to the rubber industry.
The rubber auxiliaries may be used in familiar amounts determined inter alia by factors including the intended use. Customary amounts may, for example, be amounts of 0.1% to 50% by weight based on rubber. Crosslinkers used may be peroxides, sulfur or sulfur donor substances. The rubber mixtures according to the invention may moreover comprise vulcanization accelerators. Examples of suitable vulcanization accelerators may be mercaptobenzothiazoles, sulfenamides, thiurams, dithiocarbamates, thioureas and thiocarbonates. The vulcanization accelerators and sulfur may be used in amounts of 0.1% to 10% by weight, preferably 0.1% to 5% by weight, based on 100 parts by weight of rubber.
The rubber mixtures according to the invention can be vulcanized at temperatures of 100° C. to 200° C., preferably 120° C. to 180° C., optionally at a pressure of 10 to 200 bar. The blending of the rubbers with the filler, any rubber auxiliaries and the thioether silanes can be conducted in known mixing units, such as rolls, internal mixers and mixing extruders.
The rubber mixtures according to the invention can be used for production of moulded articles, for example for the production of tyres, especially pneumatic tyres or tyre treads, cable sheaths, hoses, drive belts, conveyor belts, roll coverings, footwear soles, gasket rings and damping elements.
Advantages of the inventive thioether silanes of the formula I are improved abrasion resistance, and elevated dynamic stiffness in rubber mixtures.
Determinations of purity were made by gas chromatography or NMR.
Gas chromatography: temperature programme: 70° C.-5 min-20° C./min-260° C.-15 min; column: Agilent HP5, length: 30 m-diameter: 230 μm-film thickness: 0.25 μm; detector: TCD. NMR spectra were recorded on a 400 MHz NMR instrument from BRUKER. The spectra were each calibrated to the signal of tetramethylsilane at 0.00 ppm for 1 H, 13C and 29Si spectra. In determinations of purity, tetramethylbenzene or dimethyl sulfone was used as internal standard.
To an initial charge of tert-butylthiol (119 g; 1.10 eq) was added dropwise sodium ethoxide (w=21%; 408 g; 1.05 eq). The mixture was stirred at 60° C. for about 1 h. Subsequently, CPTEO (289 g; 1.00 eq) was added dropwise at 60° C. Then the reaction mixture was refluxed for 5 h and then excess low boilers and solvent were removed by distillation at standard pressure. The distilled suspension was filtered and the crude product (filtrate) was distilled overhead by means of vacuum distillation (boiling point 90-95° C. and 0.6 mbar). (3-(tert-Butylthio)propyl)triethoxysilane (72% yield, purity: 99.6 a% determined by GC) was obtained as a clear colourless oil.
Under a protective gas atmosphere, ethanol (260 g; 11.9 eq) and elemental sodium (11.5 g; 1.00 eq) were used to prepare ethanolic sodium ethoxide solution. Thereafter, 3-mercaptopropyltriethoxysilane was added dropwise. On completion of addition, stirring was continued for 30 min. The reaction solution was heated to 60° C. by means of an oil bath, and 1-bromoethylbenzene was added dropwise within 20 min. The reaction mixture was stirred at 60° C. for a further 11 h. After the reaction had ended, the suspension was filtered and freed of low boilers by distillation. Triethoxy(3-((1-phenylethyl)thio)propyl)silane (93% yield, purity: >95% (NMR)) was obtained as a clear yellow oil.
An initial charge of 3-mercaptopropyltriethoxysilane (327 g; 1.0 eq), 1,1-diphenylethylene (247 g; 1.0 eq) and aluminium chloride (10.1 g; 2.0% by weight) at room temperature was stirred and heated to 80° C. by means of an oil bath. The mixture was stirred at this temperature for a further 33 hours and then cooled down to room temperature. Finally, the low boilers were removed by means of distillation.
(3-((1,1-Diphenylethyl)thio)propyl)triethoxysilane (yield: 63%, purity: 61.8% by weight (from combination of 13C and 29Si NMR with dimethyl sulfone as internal standard)) was obtained as a pale yellowish liquid.
Secondary components were 1,3-bis(3-((1,1-diphenylethyl)thio)propyl)-1,1,3,3-tetraethoxydisiloxane (28.2% by weight), triethoxy(3-(ethylthio)propyl)silane (4.6% by weight), 3-(triethoxysilyl)propanethiol (0.3% by weight), diphenylethylene (5.1% by weight).
An initial charge of 3-mercaptopropyltriethoxysilane (403 g; 1.0 eq), α-methylstyrene (200 g; 1.0 eq) and aluminium chloride (8.12 g; 2.0 mol %) at room temperature was stirred and heated to 100° C. by means of an oil bath. The mixture was stirred at this temperature for 16 hours and then left to cool down to room temperature. Then it was filtered and the low boilers were removed by means of distillation.
Triethoxy(3-((2-phenylpropan-2-yl)thio)propyl)silane (yield: 99%, purity: 80.1% by weight (from combination of 13C and 29Si NMR with dimethyl sulfone as internal standard)) was obtained as a colourless liquid.
Secondary components were 1,1,3,3-tetraethoxy-1,3-bis(3-((2-phenylpropan-2-yl)thio)propyl)disiloxane (11.6% by weight), triethoxy(3-(ethytthio)propyl)silane (5.1% by weight), 3-(triethoxysityl)propanethiot (0.9% by weight), α-methylstyrene (0.7% by weight), α-methylstyrene dimer (1.6% by weight).
Triethoxy(3-((2-phenylpropan-2-yl)thio)propyl)silane (from Example 2, 106.2 g; 1.0 eq), 3,6,9,12,15-pentaoxaoctacosan-1-ol (125.3 g; 1.0 eq) and titanium tetrabutoxide (53 μl; 0.05% by weight/triethoxy(3-((2-phenylpropan-2-yl)thio)propyl)silane) added. The mixture was heated to 140° C., the ethanol formed was distilled off and, after 1 h, a pressure of 400-600 mbar was established. After 1 h, the pressure was reduced to 16-200 mbar and the mixture was stirred for 4 h. Subsequently, the reaction mixture was allowed to cool to room temperature and the reaction product is filtered. 7,7-Diethoxy-2-methyl-2-phenyl-8,11,14,17,20,23-hexaoxa-3-thia-7-silahexatriacontane (yield: 99%, transesterification level 33% polyether alcohol/Si) was obtained as a viscous liquid.
The determination of purity and the analysis of the esterification level were made by means of 13C NMR. In the NMR, the shift of the CH2 group at 61.8 ppm (adjacent to the OH group) compared to the bound variant at 61.9-62.1 ppm is characteristic, and it is possible to make a comparison against remaining ethoxy groups on the silicon atom at 58.0-58.5 ppm.
The materials used are listed in Table 1. Test methods used for the mixtures and vulcanizates thereof were effected according to Table 2. The rubber mixtures were produced with a GK 1.5 E internal mixer from Harburg Freudenberger Maschinenbau GmbH.
The mixture formulation is listed in Table 3.
The mixture production is described in Table 4.
The results of physical tests on the rubber mixtures specified here and vulcanizates thereof are listed in Table 5. The vulcanizates were produced from the untreated mixtures from the third stage by heating at 165° C. for 14 min under 130 bar.
As apparent from Table 5, mixtures 3-6 comprising the inventive silanes, by comparison with comparative mixtures 1 and 2, have a lower difference in modulus in the RPA strain sweep, which indicates a reduced filler network. Moreover, the vulcanizates of these mixtures show a significant reduction in abrasion in the DIN test.
The mixture formulation is listed in Table 6.
The mixture production is described in Table 7 and Table 8.
The results of physical tests on the rubber mixtures specified here or vulcanizates thereof are listed in Table 9. The vulcanizates were produced from the untreated mixtures from the third stage by heating at 165° C. for 17 min under 130 bar.
As apparent from Table 9, the vulcanizates of mixtures 9 and 12 comprising the silane according to the invention, compared to comparative mixtures 7 and 8 or 10 and 11, show an improvement in abrasion resistance according to DIN with simultaneously higher dynamic stiffness.
The mixture formulation is listed in Table 10.
The mixture production is described in Table 11.
The results of physical tests on the rubber mixtures specified here or vulcanizates thereof are listed in Table 12. The vulcanizates were produced from the untreated mixtures by heating at 150+ C. for 17 min under 130 bar.
It is apparent from Table 12 that the vulcanizates of mixtures 15-17 comprising the silanes according to the invention have improved tensile strength, and an improved 300% modulus and strengthening factor (M300%/M100%). Furthermore, the mixtures show advantages in abrasion resistance according to DIN with simultaneously higher dynamic stiffness.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2018 212 672.0 | Jul 2018 | DE | national |
| 10 2018 214 229.7 | Aug 2018 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/069055 | 7/16/2019 | WO | 00 |
