Vulcanizable rubber mixture based on halogen free rubber for vulcanizing these rubber mixtures and use of the rubber mixtures

© Start of patent duration: 1935 05 15 Longest possible duration:

t Issued: 1 986 01 10

Inventor:

© dependence:

AT 379 404 © References contemplated by the prior art:

Nr.379404

The invention relates to moldable and vulcanizable rubber mixtures based on halogen-free rubbers containing as essential constituents except the rubber, which contains no halogen in the molecule, a siliceous filler, optionally in admixture with the filler carbon black, optionally sulfur and or or sulfur donors, at least one vulcanization accelerator and at least one organosilane having at least one alkoxysilyl group.

It is known that the use of silica fillers in place of carbon black in rubber mixtures based on so-called all-purpose rubbers (abbreviated AP rubbers, ie rubbers that have found most extensive use for the most popular applications such as in particular styrene-butadiene rubber Butadiene rubber, butadiene-acrylonitrile rubber and natural rubbers) are limited for the following three property-related reasons:

1. In AP rubbers, silica fillers with comparable specific surface area as the carbon blacks produce significantly higher Mooney viscosities than carbon blacks.

Second Silica fillers negatively affect the cure kinetics and cure yield of the accelerated sulfur cure used with AP rubbers.

Third Silica fillers have lower rubber-effective surfaces in rubber mixtures and vulcanizates, which is very strong in reduced performance, especially in abrasion resistance.

It is known that these important disadvantages have been overcome by using organosilanes in the silica-filled rubber blends. Such organosilanes must be bifunctional, ie, firstly, a filler-active function, usually practiced by alkoxysilyl groups, and, second, a rubber-active function usually associated with sulfur-containing groups, such as -δ_χ(x = 2 to 6) and the -SH groups is exercised. The latter groups appear to be involved in the accelerated sulfur vulcanization reaction.

Highly suitable organosilanes are, for example, the outstandingly suitable bis (alkoxysilylalkyl) oligosulfides, for example the bis (triethoxysilylpropyl) tetrasulfide (German Pat. No. 2,255,557). An alternative to the separate addition of siliceous fillers and silanes to the rubber mixtures consists in prior mixing of said substances (US Pat. No. 3,997,356). In this way, silicic acid-containing vulcanizates, which provide soot-equivalent performance in highly stressed articles such as tire treads, disadvantage of the aforementioned compounds is the multi-stage production, ie the high technical complexity, which is reflected in corresponding prices.

It is also already a crosslinkable rubber mixture, which oligosulfidische organosilanes, known vulcanization accelerators and as a filler containing a siliceous filler, but no elemental sulfur, known (BE-PS Nos., 832,970 or DE-PS No. 2536674). One can simply describe the networking carried out as sulfur-free silane crosslinking.

For blends based on SBR and EPDM rubbers, mercaptosilanes such as 3-mercaptopropyltrimethoxysilane, vinylsilanes such as vinyltrimethoxysilane and aminosilanes such as 3-aminopropyltriethoxysilane have also become known (Rubber World, October 1970, pages 54 and 55).

Also, siliceous filler-containing rubber blends have been proposed based on the selected group of halogen-containing rubber grades, which blends include, but are not limited to, certain readily available and readily available halogen-containing silanes. It had surprisingly been found that these mixtures give very valuable vulcanization products.

It was even more surprising when it was now found that the same, simply constructed halogen-containing silanes in rubber mixtures based on such rubbers containing no halogen bound in the molecule, the vulcanization process or the crosslinking kinetics

No. 3,779,404 and vulcanizates whose characteristics can be described as particularly valuable and sometimes outstanding, such as, for example, the elasticity properties which were determined, for example, by testing the compression set.

The invention thus provides a vulcanizable rubber mixture of at least one vulcanizable halogen-free rubber or of a mixture of one or more halogen-free rubbers with a maximum of 80%, based on the weight of the total rubber, at least one halogen-containing rubber, further at least one siliceous filler in quantities of 1 to 250 parts by weight, at least one oxide of the metals zinc, magnesium and lead in amounts of 0 to 15 parts by weight, at least one monobasic fatty acid having 12 to 24 carbon atoms in the alkyl chain, benzoic acid or salicylic acid in amounts of 0 to 10 parts by weight, optionally sulfur and / or sulfur donors in amounts of 0.1 to 15 parts by weight, at least one vulcanization accelerator in Amounts of from 0.1 to 10 parts by weight, of at least one plasticizer in amounts of from 0 to 100 parts by weight, of at least one stabilizer from the group of anti-aging agents, anti-fatigue agents, Oxydationsschutzmittel, light stabilizers and antiozonants in amounts of 0 to 10 parts by weight, carbon black in amounts of 0 to 150 parts by weight, optionally further customary rubber excipients in conventional amounts, and from at least one organosilane, which is characterized in that Rubber mixture as organosilane 0.1 to 20 parts by weight of at least one compound of the general formula

X is -CH, -SiR '(OR), pm. 2 m + 1 - pn 3-n (I), in which X is chlorine or bromine, p = 1 or 2, m = 1 to 5, R¹ a Cj to C₅Alkyl group, a C₅- to 0_θCycloalkyl group or the phenyl group, R a Cj- to C₅Alkyl group, a C₅ - to C_a Cycloalkyl group containing methoxy ethyl group, the phenyl group or the benzyl group and n = 0, 1 or 2, a hydrolyzate and / or condensate of organosilane (I), all of the stated amounts are based on 100 parts by weight of the rubber.

To the haloalkyloxysilanes (I) which according to the invention must be present in the diene rubber mixtures in amounts of 0.1 to 20 parts by weight, preferably 1 to 15 parts by weight, based on 100 parts by weight of the rubber; include in particular the following silanes: Chloromethyltrimethoxysilane, Chlormethy ltriäthoxysilan, Brommethyltriäthoxysilan, Dichlormethyltriäthoxysilan, 1-Chloräthyltrimethoxysilan, 2-Chloräthyltrimethoxysilan, 2-Bromäthyltrimethoxysilan, 2,2-Dibromäthyltrimethoxysilan, 3-bromopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3,3-Dichlorpropyltrimethoxysilan, 3-Chlorpropyltriäthoxysilan, 3-Brompropyltriäthoxysilan, 3 , 3-dibromopropyltriethoxysilane, 1-bromo-2-propyltripropoxysilane, 2,2-dichloroethyltri-n-butoxysilane, 2-chloroethyltri-isobutoxysilane, 3-bromopropyltri-t-butoxysilane, 3,3-dibromopropyltri-isopropoxysilane, 3-bromopropyltri-n-pentoxysilane, 2-chloroethyl, hyltri-n-butoxysilane, 2-bromo-n-propyldimethoxyethoxysilane, 3 3-dichloropropylmethoxyethoxypropoxysilane, 3-chloropropyldimethoxymethylsilane, 3-bromopropyldiethoxyethylsilane, 3-chloropropylethoxydiethylsilane, 3-bromopropyltris (methoxyethoxy) silane, 3-chloropropyldiethoxyphenylsilane, 3,3-dichloropropyldimethoxycyclopentylsilane, 3-bromopropyl-di-n-propoxycyclohexylsilan,

3-chloropropyldicyclohexoxycyclohexylsilane, 3-bromopropyldiethoxycycloheptylsilane, 3-chloropropylethoxyphenyloxyethylsilane, 3,3-dibromopropylbenzyloxyethoxyethylsilane, 4-chloro-n-butyltrimethoxysilane,

4- bromobutyltrimethoxysilane, 3-chloro-2-methylpropyltrimethoxysilane, 3-chloro-n-butylcyclooctyldipropoxysilane, 3-chloro-2-ethylpropyldiethoxymethylsilane, 3-bromo-n-pentyldimethoxymethylsilane, 3-chloro-2-methylpropyldimethoxyphenylsilane, 5-chloro-n pentyltriethoxysilane, 1-bromo -4-n-pentylcyclooctoxydimethoxysilane, 4-bromo-2-methylbutyltriethoxysilane, 2-chloro-n-propyltripentoxysilane, 2,2-dichloro-2-n-propyltributyloxysilane, 3-bromopropyltriphenoxysilane, 3-chloropropyltribtribyloxysilane,

3,3-dibromopropyltricyclopentoxysilane and 3-bromopropyltri-n-pentoxysilane. The halogenoalkyloxysilanes having a halogen atom [p = 1 in the formula (I)] and having three alkoxysilyl groups are preferred.

The silanes of the formula (I) having two halogen atoms include, in particular, dibromomethyltriethoxysilane, dichloromethyltriethoxysilane, 2,2-dichloroethyltriethoxysilane, 2,2-dibromoethyltri-n-propoxysilane, 3,3-dichloropropyltriethoxysilane, 1,1-dichloro-2-n propyltriethoxysilane, 1,1-dibromo-2-n-propyltri-i-propoxysilane, 3,3-dichloropropyltri-n-propoxysilane, 3,3-dibromopropyltri-n-but-4, No.379404 oxysilane, 4,4-dichlorobutyltriethoxysilane , 4,4-dibromobutyltri-n-propoxysilane, 5,5-dichloropentyltriethoxysilane, 5,5-dibromopentyltri-n-propoxysilane and mixtures of these.

An advantageous embodiment of the rubber mixture according to the invention is characterized in that it additionally contains, per 100 parts by weight of rubber, 0.5 to 10 parts by weight of at least one organosilane of the formulas t R (RO)₃__n Si-Alk]₂ S _χ (II) and / or ^Rn^(R0)3-n^Si_Alk~^{SH (III)}>

in which R and R¹ e is an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms or the phenyl radical, wherein all R and R are radicals¹ each may have the same or a different meaning, n = 0, 1 or 2, Alk is a bivalent, straight or branched hydrocarbon radical having 1 to 10 carbon atoms and x is a number from 2.0 to 8.0, a hydrolyzate and / or a Condensate of organosilanes (II) and (III) contains.

In place of the silanes of the formulas (I), (II) and (III) may also occur their hydrolysates and condensates, optionally partially, which means mixtures of the unhydrolyzed or non-condensed silanes with the hydrolyzed and / or condensed silanes , This hydrolysis or condensation need not be complete, so that partial hydrolysates or partial condensates can also be used according to the invention. These partial hydrolysates or Partial condensates are possible because the silanes have multiple oxysilyl groups in the molecule [s. Can possess formula [II]] or [s. Formulas (I) and (III)].

The condensates include in particular the condensates of silanes with alcohols, preferably dihydric alcohols such as ethylene glycol, propylene glycol, trimethylene glycol, trimethylethylene glycol, tetramethylene glycol, pentamethylene glycol, etc., diethylene glycol, butanediols such as 1,4-butanediol, dipropylene glycol, polyethylene glycols and glycidol (2.3 -Epoxypropanol-l).

The hydrolysis as well as the condensation reactions are carried out according to known methods. They lead to higher molecular weight compounds with, for example, higher boiling points, etc., which may be advantageous for the preparation of the rubber mixtures according to the invention.

Silanes of the formula (I) are prepared by processes known per se, for example, from halides still containing at least one hydrogen atom by catalytically controlled additions to a halogenated hydrocarbon having a CC double bond (hydroxylylation). The halogen atom or atoms present on the silicon atom are then converted into alkoxysilanes in a likewise known reaction, for example by alcoholysis. It has also been found that the raw silanes derived from the production can be used directly for the purposes of the invention with good results if they are virtually free of hydrolyzable halide and hydrogen halide or have been freed from this by treatment with ammonia or sodium hydride a rectification can follow.

The rubbers used according to the invention include all rubbers still containing C - C double bonds and crosslinkable with sulfur and vulcanization accelerator (s) to give elastomers and mixtures thereof which contain no halogen in the molecule; in particular so-called diene elastomers. These include, for example, natural and synthetic rubbers which may be oil extended, such as butadiene rubbers, isoprene rubbers, butadiene-styrene rubbers, butadiene-acrylonitrile rubbers, butyl rubbers, terpolymers of ethylene, propylene and non-conjugated dienes, carboxylic rubbers, epoxy rubbers and trans-polypentenamers. Rubber blends of said rubbers with other polymers in proportions, which are generally not more than 80 wt .-%, preferably less than 50%, based on the weight of the total rubber, are also usable according to the invention, including, for example, halogenated butyl rubbers, in particular brominated or chlorinated butyl rubbers, chlorinated rubbers, rubber hydrochlorides, and especially the polymers of 2-chlorobutadiene-1, 3, Further, chlorosulfonated polyethylene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, cheNr.379404

- 5 mixed derivatives of natural rubber and modified natural rubbers count. Diene rubbers and EPDM polymers and their blends are preferred.

The silicatic fillers which can be used according to the invention, also as a mixture of two or more fillers, are fillers known per se in rubber technology. The term silicate filler is broad and refers to compatible with rubber fillers or incorporated into rubber mixtures fillers consisting of silicates, silicates and / or contain silicates chemically bound in the broadest sense.

In particular, the siliceous fillers include fumed silica fillers consisting essentially of silicon dioxide with specific surface areas in the range of about 5 to 1000, preferably 20 to 400 m²/ g (according to the nitrogen adsorption method, which is described in the German industrial standard DIN 66132, measured) and with primary particle sizes in the range of about 10 to 400 nm, which can be prepared for example by precipitation, hydrothermal digestion, by hydrolytic and / or Oxidative high-temperature conversion, also called flame hydrolysis, of volatile silicon halides (fumed silica) or by an arc process. If appropriate, these siliceous fillers may also be present as a mixed oxide or oxide mixture with the oxides of the metals aluminum] magnesium, calcium, barium, zinc and / or titanium. They may also optionally have been rendered hydrophobic in a known manner with silanes.

Synthetic silicates, for example aluminum silicates or alkaline earth silicates such as magnesium or calcium silicate, with specific surface areas of about 20 to 400 m²/ g and primary particle sizes of about 10 to 400 nm.

Natural silicates, such as kaolins, clays and asbestos as well as natural silicas such as quartz and kieselguhr.

Glass fibers and glass fiber products such as mats, strands, fabrics, scrims and the like. and glass microspheres.

The silicate fillers mentioned are preferably used in amounts of about 10 parts by weight or optionally even lower up to about 250 parts by weight, based on 100 parts by weight of the rubber polymer.

As filler mixtures may be mentioned: silica / kaolin or silica / glass fibers / asbestos and blends of silicate-containing reinforcing fillers with the known rubber, eg silica / HAF carbon black or silica / glass fiber cord / ISAF carbon black.

According to the invention, highly disperse or active silicic acids are preferred as siliceous fillers, in particular the precipitated silicas and preferably in amounts of from 5 to 150 parts by weight, based on 100 parts by weight of rubber.

Carbon black may additionally be present in the rubber mixtures according to the invention, not only for gray or black dyeing of the vulcanizates, but for the achievement of special, valuable vulcanizate properties, the known rubbers being preferred. The carbon black is used in amounts of from 0 to 150 parts by weight, based on 100 parts by weight of rubber, in the new rubber mixtures.

In the case of the presence of silicate filler and at the same time carbon black in the rubber mixtures, the total filler content, based on 100 parts by weight of rubber, is limited to a maximum of 300 parts by weight, preferably 150 parts by weight are considered to be the upper limit.

A lower limit of zero means in the context of the invention that the mixture component may be present in the rubber mixture, but need not. So, for example, if soot is present in a mixture, the lower limit is practically set at 0.05 parts by weight.

It has proven to be particularly advantageous in practice to mix one or more halosilanes of the formula (I) before incorporation into the constituents of the rubber mixture with the desired siliceous filler and / or the carbon black, for example with a HAF carbon black the specification N 330 (specific surface according to DIN 66132 is 78 m²/G. Average primary particle size 27 nm. Dibutyl phthalate absorption according to DIN 53601 is 100 ml / 100 g) or a silica filler (specific surface area between 160 and 190 m²/G. Mean primary particle size

Nr.379404

- 6 18 nm), thus to produce a premix of one or more of the silanes and fillers and to further process this premix with the or certain mixture constituents. Such premixes are preferably by weight 1: 1 mixtures of halosilane and filler such as a mixture of equal parts by weight of 3-chloropropyltriethoxysilane and precipitated silica filler or carbon black or silica filler and carbon black. Such silica fillers, in particular highly dispersed type with specific surfaces between about 100 and 250 m^z/ g, are described above, as are the carbon blacks. In particular, the soot types processed in the rubber industry are used.

The accelerators or vulcanization accelerators used are the accelerators used in the rubber industry and most commonly used for a number of rubbers. However, if halogen rubbers are also used, special vulcanization accelerators may also be used. The vulcanization accelerators which can be used include the dithiocarbamate, xanthate and thiuram accelerators, furthermore the thiazole accelerators, which include the mercapto and sulfenamide accelerators, amine accelerators or aldehyde amine accelerators, basic accelerators, which include, for example, the guanidine accelerators and other basic accelerators; (see Vulcanization and vulcanization aids, summary by Dr. W. Hofmann, Leverkusen, Verlag Berliner Union, Stuttgart, 1965, pages 114 ff, especially page 122) and - regardless of the above division - the general Vulkanisationsbeschleunigerklassen the mercapto, disulfide, polysulfide, sulfenamide, thiazole and thiourea accelerator.

The thiuram accelerators are essentially the tetraalkyl or dialkyldiarylthiuram mono-, di- and tetrasulfides such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, dipentamethylenethiuram monosulfide, disulfide, tetrasulfide and hexasulfide, dimethyldiphenylthiuram disulfide, diethyldiphenylthiuram disulfide, etc.

The dithiocarbamate accelerators are generally derivatives of the dialkyl, alkylcycloalkyl and alkylaryldithiocarbamic acids. Two known representatives of this accelerator class are the N-pentamethylene-ammonium-N'-pentamethylenedithiocarbamate and the zinc dialkyldithiocarbamates.

Xanthate accelerators are the known derivatives of alkyl and arylxanthogenic acids such as zinc ethylxanthogenate.

The mercapto accelerators include, in particular, 2-mercaptobenzothiazole, 2-mercaptoimidazoline, mercaptothiazoline and a number of monomercapto and dimercaptotriazine derivatives (see, for example, British Pat. No. 1,095,219). Mercaptotriazine accelerators are, for example, 2-diethanolamino-4,6-bis-mercaptotriazine and 2-ethylamino-4-diethylamino-6-mercapto-s-triazine.

Disulfide and sulfenamide accelerators are disclosed, for example, in British Patent No. 1,120,862, including 2-diethylamino-4,6-bis- (cyclohexylsulfenamido) -s-triazine, 2-di-n-propylamino-4,6 bis (N-tert-butylsulfenamido) -s-triazine, and especially N-cyclohexyl-2-benzthiazolesulfenamide. The disulfide accelerators include, for example, the bis (2-ethylamino-4-diethylaminotriazin-6-yl) disulfide, the bis (2-methylamino-4-di-isopropylamino-triazin-6-yl) disulfide, and the dibenzothiazyl disulfide.

Other sulfidic triazine accelerators are the polysulfidic or oligosulfidic triazine derivatives and their polymers, which are prepared according to DE-OS 2027635 and are also disclosed in GB-PS No. 1,353,532. These accelerators are also sulfur donors.

The aldehyde amine accelerators include condensation products of saturated or unsaturated aliphatic aldehydes with ammonia or aromatic amines such as butyraldehyde aniline and butyraldehyde butylamine. Other basic accelerators are, for example, guanidine derivatives such as diphenylguanidine and di-o-tolylguanidine and amine accelerators such as hexamethylenetetramine and others

The thiourea accelerators include, for example, the thiourea itself and the diaryl thioureas such as the 1,3-diphenyl-2-thiourea.

In accordance with the invention, it may be advantageous to use mixtures of two, three or more different accelerators such as disulfide promoters such as the di-2-benzothiazyl disulfide with thiuram accelerators such as tetramethylthiuram disulfide together with sulfur which may be wholly or partly insoluble sulfur or with sulfur donors like morpholine disulfide.

- 7 No. 379404

The accelerators are used according to the invention in conventional amounts, preferably in amounts of 0.2 to 10 parts by weight, based on 100 parts by weight of the rubber.

Stabilizing agents which are known per se, in particular those from the group of anti-aging agents, anti-fatigue agents, antioxidants, light stabilizers and antiozonants, as well as mixtures of these, can advantageously be present in the rubber mixtures according to the invention, i.zw. in amounts of 0.2 to 10 parts by weight, based on

100 Parts by weight of the rubber.

Further, plasticizers or plasticizing oils may be added to the rubber blends, for example, highly aromatic naphthenic or paraffinic process oils, advantageously those having low pour points, such as between 0 to -60 ° C. The amount of plasticizer oil can vary within wide limits, it may be more than 0.5 or 5 parts by weight, in particular more than 10 parts by weight to about 100 parts by weight, in each case based on 100 parts by weight , in each case based on 100 parts by weight of rubber.

The new rubber blends preferably contain an organic, room temperature solid acid such as those used in rubber technology in amounts of from 0.2 to 10 parts by weight, based on 100 parts by weight of the rubber, preferably fatty acids such as Stearic acid, palmitic acid or corresponding acids of the homologous series of 12 to 24 carbon atoms in the molecule, furthermore benzoic or salicylic acid.

Furthermore, the rubber mixtures according to the invention, oxides of polyvalent Me20, as they are also used in rubber technology, in amounts of 0.1 to

Parts by weight, based on 100 parts by weight of the rubber.

Among these metal oxides is primarily zinc oxide, especially in finely divided and / or active form. Furthermore, usable are magnesium oxide or optionally lead oxide. These oxides are preferably used in finely divided, active or powdery form. It is also possible to use mixtures of the metal oxides, in particular with the desired co-use of, for example, polychlorobutadiene, in which case said metal oxides have a crosslinking effect on this elastomer.

The oligosulfidic organosilanes of the formula [RHRO), Si-alk-] S (II), n 3 - n 2 x in which R and R are¹ an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, the Methoxyäthyl- or the phenyl radical, wherein all radicals R and R¹each may be the same or different, n is 0, 1 or 2, Alk is a divalent straight or branched chain hydrocarbon radical of 1 to 10 carbon atoms and x is an integer from 2.0 to 8.0, preferably to 6.0 in amounts of 0.5 to 10 parts by weight per

100 Parts by weight of rubber in the mixtures according to the invention may be contained are known per se, for example from US Pat. No. 3,873,489. They are prepared by the process described in DE-PS No. 2,542,534 (US Pat. No. 4,072,701).

Examples of such and preferably used organosilanes are the bis (trialkoxysilylalkyl) -oligosulfides such as bis- (trimethoxy-, - (triethoxy-, - (trimethoxyethoxy-, -tri- (n-propoxy-, 40- {tributoxy-, - ( tri-isopropoxy- and - (tri-isobutoxysilylmethyl) -oligosulfide, and the corresponding -silyläthyl) -oligosulfide, u.zw. in each case the di-, tri-, tetra-, penta-, hexa-, hepta- and octasulfides, furthermore the bis- (3-trimethoxy-, - (triethoxy-, -tri- (methoxyethoxy-, - (tripropoxy-, - (tri-n-butoxy- and - (tri-isobutoxysilylpropyl) -oligosulfide, u.zw. again the di-, tri-, Tetrausw. up to the octasulfides, further the corresponding bis (3-trialkoxysilylisobutyl) -oligo45 sulfides , the corresponding bis- (4-trialkoxysilylbutyl) -oligosulfides, etc., to the bis (10-trialkoxysilyldecyl) -oligosulfides. Of these selected, relatively simply constructed trialkoxysilanes and mixtures thereof of the general formula (II), the bis- (3-trimethoxy-, - (triethoxy- and - (tripropoxysilylpropyl) -polysulfides, or the di-, tri, are preferred - And tetrasulfides, in particular the triethoxy compounds having 2, 3 or 4 sulfur atoms and mixtures thereof. Preferably, these oligosulfidic silanes are used in amounts of from 1 to 15 parts by weight per 100 parts by weight of siliceous filler in the new, preferably vulcanizable with sulfur rubber Mischurigen.

Nr.379404

Instead of the mentioned oligosulfidic alkoxy- or phenoxysilyl compounds, their wholly or partially hydrolyzed compounds may occur or these may replace a proportion of the unhydrolysed compounds.

The following mercaptosilanes of the formula (III) are preferably used:

Mercaptomethyltrimethoxysilane, Mercaptomethyltriäthoxysilan, Mercaptomethyltri-isopropoxysilan, 2-Mercaptoäthyltrimethoxysilan, 2-Mercaptoäthyltriäthoxysilan, 2-Mercyptoäthyltri-isopropoxysilan, 2-Mercaptoäthyltributoxysilan, 2-Mercaptoäthyltri-n-propoxysilane, 2-Mercaptoäthyldiäthoxymethylsilan, 2-mercapto-n-propyltriäthoxysilan, l-mercapto 2-n-propyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltri-isopropoxy-silane, 3-mercaptopropyltri-n-propoxysilane, 3-mercaptopropyltributoxysilane, 3-mercaptopropyltris (methoxyethoxy) silane, 4-mercaptobutyltriethoxysilane, 5-mercaptopentyltrimethoxysilane, 5-mercaptopentyltri-isopropoxysilane, 3-mercaptopropyldiethyethoxyethylsilane, 3-mercaptopropyldipropoxypropylsilane, 6-mercaptohexyltriethoxysilane , 8-mercaptooctyltrimethoxysilane and 10-mercaptodecyltriethoxysilane.

The rubber mixtures are prepared in the usual way. A two-stage mixing cycle is preferred. In the first stage are in a kneader at flow temperatures between 55 and 85 ° C, preferably of 60 ° C. the following components are mixed:

within the first minute of the rubber and in the additional presence of a halogen rubber also a metal oxide, for example magnesium oxide;

within the then one and a half minutes, half of the siliceous filler, zinc oxide, stearic acid and silane (s);

within the following one and a half minutes, the second half of the siliceous filler and, optionally, the plasticizer (eg, process oil) and the remaining mixture components except the sulfur and the accelerator;

after a total of four and a half minutes, the mixture is extracted from the kneader and stored for 24 h at room temperature.

In the second mixing stage, the sulfur and the accelerator (s) are admixed to the premix from the first mixing stage on a pair of rolls or in a kneader at an initial temperature of about 80 ° C. within 1 1/2 minutes.

This two-stage mixing process avoids premature scorching of the mixture.

The course of vulcanization of a rubber mixture can be represented, for example, by means of a vulcanizer curve. The volumetric curve is created by applying the moments determined by a Vulkameter (see DIN 53529) on the abscissa of a rectangular coordinate system against the vulcanization time on the ordinate. The onset of vulcanization shows up in a rising branch of the volcano curve. The curve then usually reaches a maximum or indicates a maximum value in order to fall more or less rapidly or slowly in the course of further vulcanization in most cases. At the same temperature recorded volcano curves can also be referred to as crosslinking isotherms.

In the vulcanization of rubber mixtures on the basis of natural or synthetic rubbers in the presence or absence of rubber fillers with the aid of sulfur and vulcanization accelerators, which are usually carried out in industry, the said crosslinking isotherms usually undergo a maximum, which results from that during the complex chemical processes in the vulcanization in the initial stage of the construction of polysulfidic crosslinks between the rubber molecules predominates, in the final stage, however, the degradation of intermolecular polysulfide and disulfide bonds to intramolecular heterocyclic rings. These processes are characterized by a volcanic determined crosslinking isotherm by a continuous decrease of the cross-linking isotherm, ie a drop in the torque values ​​as well as in practice by moduli falling with increasing vulcanization time. The change in the relative crosslink density of the vulcanizate (magnitude of the torques) as well as the relative density of crosslinking present at any point in the vulcanization can be read off from the course of the vulcanized isotherm. Parallel to the change in the crosslinking densities is accompanied by a change in the mechanical properties of the vulcanizates, as long as this property is dependent on the crosslinking density

No.379404 such as tensile strength, breaking elongation, elasticity, Shore hardness, heat generation, abrasion, etc. The sloping branch of the Vulkameterkurve means in practice a deterioration of the said properties of the vulcanizate. This phenomenon is called in technical language by the term reversion.

The invention also relates to the process for vulcanizing the rubber mixtures.

Industrial applications for the claimed rubber mixtures and their vulcanizates are, for example:

Technical rubber goods such as cable sheaths, hoses, airbags, electrical insulation, linings, impregnations and coatings of heat-resistant fabrics, in particular drive belts, V-belts, conveyor belts, roll coverings, seals, but also shoe soles, damping and vibration elements and the like. Article to which high requirements with regard to elasticity properties, as can be demonstrated in particular by the test for the compression set (DIN 53517), are furthermore provided with regard to temperature and / or oil resistance.

The excellent effect of the halosilanes of the abovementioned general formula especially in halogen-free rubber-containing mixtures or moldings and their crosslinking products or vulcanizates was very surprising.

Without limiting the invention, some exemplary formulations for the novel rubber mixtures of the vulcanizates or crosslinking products, with evaluations of these results, are given below. This is repeated many different terms, so that the following abbreviations are used.

List of abbreviations used

abbreviation

Designation measured in

ML 4

MS 4

ZF

M 200

M 300

WW

BD

SH

A

CS

D.

ΙΪ1 in

D max

120 '

Mooney scorch time (130 ° C)

Mooney Cure Time (13O ° C)

Mooney plasticity or viscosity (determined at 100 ° C. with the normal rotor (L) test duration: 4 min)

Mooney plasticity or viscosity (determined at 100 ° C. with the small rotor (S) test duration: 4 min)

tensile strenght

Voltage value at 200% and

Tension value at 300% elongation (MOdul) Tearing resistance (at ° C)

elongation

Shore A hardness

Abrasion (also DIN abrasion)

Compression set (Compression Set B, h, 70 ° C) minimum torque (rheometer test) maximum torque

Torque after 120 min test duration in the rheometer min

Mooney units (torque)

Mooney units

MPa

MPa

MPa

N / mm%

mm³ / 0

nm

nm

nm

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List of abbreviations used

abbreviation

Designation measured in

D_g0, Torque after 60 min test time Nm t 10% reaction time up to 10% conversion min t 80% reaction time up to 80% conversion and min t 95% reaction time up to 95% conversion of the vulcanization reaction based on the maximum conversion (same volumetric curve) etc., including differences of the same min

auditing standards

The physical tests were carried out at room temperature according to the following standard regulations:

Tensile strength, elongation at break and stress value

<td>on 6 mm thick rings (Moduli)</td><td>DIN 53504</td>

<td>Tear strength</td><td>DIN 53507</td>

<td>Shore A hardness</td><td>DIN 53505</td>

<td>Mooney test</td><td>DIN 53523 and DIN 53524 or ASTM D 927-57</td>

<td>Abrasion, also called DIN abrasion</td><td>DIN 53516</td>

<td>Determination of the compression set of rubber</td><td>ASTM D 395</td>

<td>Rheometer / vulcametry</td><td>DIN 53529 (Pre-standard, Oct. 1972)</td>

The vulcanizates or the test specimens were produced in a steam-heated transfer press at the stated vulcanization temperatures and heating times.

In the examples, the amounts of the compounding ingredients are given in parts by weight (parts by weight).

The respective preceding comparison mixtures are marked with the letter V in front of the number. The corresponding mixtures according to the invention are marked with the prefixed letter E.

The preparation of the mixtures was carried out in two separate phases in a conventional kneader, each heated to an initial temperature of 80 ° C and the rotor was set to 40 revolutions per minute (Umdr / min). The friction was 1: 1.16.

In a mixed phase, the total amount of the rubber was first added within 1 min, then the first half of the filler, the zinc oxide, the stearic acid and the silane within about 1 1/2 min. Thereafter, the second half of the filler was also added during a 1 1/2 minute mixing time. The subsequent general cleaning of the kneader parts such as of the stamp lasted 1/2 min, and after a total mixing time of 5 min, the resulting premix was removed from the kneader.

Now the premix was stored at room temperature for 24 hours. Subsequently, the

No.379404 second mixing phase carried out with the same kneader, the same rotational speed, friction and initial temperature, wherein within 1 1/2 min the premix, the sulfur and the accelerator (s) are added and all the ingredients are mixed to a uniform distribution of the mixture components were processed.

As the results of the measurements on the rubber mixtures and the vulcanizates showed, the mixed method described is, on the whole, the most favorable. Hiebei the mixing components zinc oxide and stearic acid are used pretty much at the beginning of mixing.

The resulting mixtures are in Example 1 below with V 1.1 (comparative mixture of Example 1 No. 1), E. 1.1.1 (inventive mixture of Example 1 No. 1.1) and

E 1.2.1 (mixture according to the invention of Example 1 No. 2.1).

If, on the other hand, the zinc oxide or analogous metal oxides and the stearic acid or analogous organic acids, especially analogous fatty acids, are added and incorporated later in the course of the mixing operations, for example in the second phase, distinct differences in the properties of the mixtures and the vulcanizates become apparent For example, the Mooney Vis15 viscosities or -Plastizitäten, but also in the properties of the vulcanizates. Also, Mooney viscosities MS 4 were measured from corresponding alternative blends. These are the comparative mixtures V 1.2 and the mixtures E 1.1.2 and E 1.2.2 according to the invention.

The determination of the plasticity according to Mooney (MS 4 values) was carried out according to DIN 53523 with the

<td colspan="3">Small motor at 100 ° C test temperature (see following table) Example 1: There are three rubber mixtures</td><td colspan="2" rowspan="2">I). from the following mixture components</td>

<td rowspan="2">posed</td><td rowspan="2">mixtures</td><td rowspan="2">V 1.1 and V 1.2</td>

<td>E 1.1.1 E 1.1.2</td><td>E 1.2.1 E 1.2.2</td>

<td></td><td>Styrene-butadiene</td><td></td><td></td><td></td>

<td></td><td>(SBR 1500)</td><td>100</td><td>100</td><td>100</td>

<td></td><td>granulated, active,</td><td></td><td></td><td></td>

<td></td><td>precipitated silica</td><td></td><td></td><td></td>

<td></td><td>-Filler ¹¹</td><td>50</td><td>50</td><td>50</td>

<td></td><td>Zinc oxide, finely divided,</td><td></td><td></td><td></td>

<td></td><td>active</td><td>4</td><td>4</td><td>4</td>

<td></td><td>stearic acid</td><td>2</td><td>2</td><td>2</td>

<td></td><td>Chlorpropyltriäthoxysilan</td><td>-</td><td>3</td><td>7.5</td>

<td></td><td>N-cyclohexyl-2-benzo-</td><td></td><td></td><td></td>

<td></td><td>thiazolsulfenamid</td><td>1</td><td>1</td><td>1</td>

<td></td><td>sulfur</td><td>2</td><td>2</td><td>2</td>

<td>The</td><td>so resulting mixtures</td><td>are with V 1.1</td><td colspan="2">(Comparative mixture of example no.</td>

<td>E 1.1.1</td><td>(mixture according to the invention</td><td>of example no.</td><td>1.1) and E 1</td><td>.2.1 (inventive</td>

²⁵ Scheme of Example 1 No. 2.1).

i)

Average primary particle size of this filler 18 μσι and specific surface area (DIN 66132) 175 m²/G

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Table I

<td>mixture</td><td>V 1.1</td><td>E 1.1.1</td><td>E 1.2.1</td><td>V 1.2</td><td>E 1.1.2</td><td>E 1.2.2</td>

<td>MS 4</td><td>82</td><td>78</td><td>70</td><td>140</td><td>108</td><td>76</td>

<td>^ min</td><td>0.121</td><td>0.116</td><td>0.098</td><td>0,275</td><td>0.141</td><td>0,110</td>

<td>^D120 '</td><td>0.757</td><td>0,840</td><td>1,083</td><td>0.977</td><td>0.897</td><td>1,091</td>

<td>^D120 ^DtNin</td><td>0.636</td><td>0.724</td><td>0.985</td><td>0.702</td><td>0.755</td><td>0.981</td>

<td>t 10%</td><td>11,7-</td><td>14.7</td><td>12.0</td><td>17.2</td><td>16.1</td><td>17.2</td>

<td>t 90%</td><td>60.4</td><td>80.5</td><td>64.4</td><td>84.4</td><td>76.3</td><td>62.6</td>

<td>t 95%</td><td>71.0</td><td>93.1</td><td>86.1</td><td>95.0</td><td>89.4</td><td>74.8</td>

<td>t 90-t 10%</td><td>48.7</td><td>65.8</td><td>52.4</td><td>67.2</td><td>60.1</td><td>45.4</td>

<td>^D120¹"^d60 '</td><td rowspan="2">9.4</td><td rowspan="2">20.2</td><td rowspan="2">11.2</td><td rowspan="2">25.4</td><td rowspan="2">17.7</td><td rowspan="2">9.8</td>

<td></td>

<td>^D120'-^Dmin</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>ZF</td><td>14.0</td><td>21.6</td><td>20.0</td><td>12.9</td><td>17.3</td><td>16.5</td>

<td>M 300</td><td>3.0</td><td>4.3</td><td>8.9</td><td>3.0</td><td>4.1</td><td>8.4</td>

<td>BD</td><td>710</td><td>700</td><td>470</td><td>720</td><td>660</td><td>440</td>

<td>e</td><td>34</td><td>35</td><td>37</td><td>37</td><td>34</td><td>36</td>

<td>SH</td><td>59</td><td>61</td><td>68</td><td>61</td><td>59</td><td>66</td>

<td>A</td><td>170</td><td>124</td><td>91</td><td>169</td><td>125</td><td>87</td>

In Table I and also in the following text, the D values ​​are the torque in Newton meters (Nm) determined with the aid of a vulcanometer or rheometer. The torques are taken from volcanometrically measured cross-linking isotherms. As Vulkameter a device of the company Monsanto Europe SA B-1160 Brussels, type Rheometer MPV served. In the rheometer test, the following conditions were observed: deformation amplitude 3 °, test frequency 3 cycles / min, test temperature 160 ° C and running time 2 h. With regard to the terms vulcanization and cross-linking isotherm, reference is made to the pre-standard DIN 53529 of February 1971, in particular to sheet 1 of this pre-standard.

The numbers in Table I show that the silanes cause a significant reduction in the viscosities of the rubber mixtures according to the invention, which is equivalent to a reduction in the workload. The viscosity reduction becomes even more pronounced or more advantageous when the silane content in the mixtures is increased as shown. The viscosity can be further reduced as shown further and vice versa.

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Example 2: in a base mixture

component

Natural rubber (SMR 5, ML 4 = 67)

Silica filler (as in Example 1) zinc oxide stearic acid

silane; various

N-cyclohexyl-2-benzothiazole sulfenamide

sulfur

weight values

100 as indicated below

1.5 silanes were incorporated in each type and amount as indicated. A comparative mixture contained no silane, another mixture contained 6 parts by weight of the technical silane, consisting essentially of bis (3-triethoxysilylpropyl) -oligosulfide having a sulfur content of at least 22.0% by weight according to the prior art; in the following, this silanoligosulfide is designated by the abbreviation SO. Two mixtures according to the invention contained 6 parts of GT 3-chloropropyltriethoxysilane (abbreviated to Cl-PTES) and 8 GT of Cl-PTES.

The four mixtures were prepared as described above. The resulting rolled skin was partially formed into plates of 20 × 10 cm in size and 6 mm in thickness and vulcanized at 150 ° C. Another part of the four mixtures was subjected to rheometer testing at 150 ° C. Among other things, the following values ​​resulted.

Table II

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>D. min</td><td>3.36</td><td>0.77</td><td>0.65</td><td>0.58</td>

<td>ML 4</td><td>161</td><td>75</td><td>72</td><td>66</td>

<td>t 10%</td><td>20</td><td>15.3</td><td>29.4</td><td>31</td>

<td>t 80-t 20%</td><td>120</td><td>6.4</td><td>6.1</td><td>4.2</td>

<td>WW</td><td>7</td><td>39</td><td>42</td><td>47</td>

<td>SH</td><td>62</td><td>63</td><td>57</td><td>58</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>32.7</td><td>17.7</td><td>17.9</td><td>17.8</td>

Example 3: In the same base mixtures as in Example 2, with the exception of 100 GT poly15 isoprene rubber instead of the natural rubber, the same silanes according to the prior art (SO) and according to the invention Cl-PTES, in equal amounts, incorporated again and for comparison a mixture without added Silco added. The following values ​​were found (test execution as in example 2).

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Table III

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>D. min</td><td>4.18</td><td>1.30</td><td>1.00</td><td>0.85</td>

<td>ML 4</td><td>136</td><td>87</td><td>77</td><td>71</td>

<td>t 10%</td><td>8.5</td><td>15.7</td><td>36</td><td>39</td>

<td>t 80-t 20%</td><td>15.1</td><td>5.4</td><td>6.3</td><td>4.6</td>

<td>WW</td><td>9</td><td>33</td><td>33</td><td>39</td>

<td>SH</td><td>66</td><td>66</td><td>54</td><td>59</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>28.2</td><td>14.5</td><td>12.8</td><td>12.8</td>

From this, in particular, significant improvements in the mixing viscosities and in the values ​​for the tear strength and. the compression set can be read.

Example 4: Rubber mixtures of the following constituents were prepared and tested in analogy to the preceding examples.

ingredients

Wt, parts by

Polybutadiene rubber with 98% cis-l, 4-content

Natural Rubber (First Latex Crepe)

Silica filler (see Example 1)

Zinc oxide (red seal quality) stearic acid

Naphthenic processing oil (pour point - 28 ° C)

Anti-aging agent, a mixture of aralkylated phenols (D = 1.06 g / ml;_{Ρθ 4} = 130 ° C)

Silanes, different

Accelerator zinc ethyl phenyldithiocarbamate

Benzothiazole-2-dicyclohexyl-1-sulfenamide

Sulfur as indicated below

0.5

1.67

A comparative mixture was prepared without added silane and another comparative mixture contained 3.3 GT of the silane SO (see Example 2). The mixtures according to the invention

No. 3,779,404 contained 6 and 8 GT of the silane Cl-PTES (see Example 2).

Table IV

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 3.3 GT</td><td colspan="2">with Cl-PTES</td>

<td>2 GT</td><td>4 GT</td>

<td>D.</td><td>3.18</td><td>1.32</td><td>1.79</td><td>1.14</td>

<td>min</td><td></td><td></td><td></td><td></td>

<td>ML 4</td><td>148</td><td>51</td><td>62</td><td>58</td>

<td>t 10%</td><td>-</td><td>8.8</td><td>12.8</td><td>13.4</td>

<td>t 80-t 20%</td><td>120</td><td>3.4</td><td>5.4</td><td>3.1</td>

<td>WW</td><td>23</td><td>17</td><td>18</td><td>26</td>

<td>SH</td><td>62</td><td>58</td><td>47</td><td>50</td>

Example 5: From the following mixture constituents and quantities, rubber mixtures were prepared as described above and these were tested in analogy to the preceding examples.

ingredients

Parts by weight

Styrene-butadiene rubber (SBR 1712) 96.2 cis-l, 4-polybutadiene rubber (see Example 4) 30 precipitated, active, granulated

Silica filler [average primary particle size 28 gm, specific surface area (DIN 66132)

130 m^z / g] 30

Rubber nut N 339 40

Zinc oxide (see Example 4) 4

Stearic acid 2

N-isopropyl-N'-phenyl-p-phenylenediamine 2

Poly-2,2,4-trimethyl-1,2-dihydroquinoline 1

Ozone protection wax (paraffin base,

Solidification point 61-65 ° C, type G 35) 1

Process oil, highly aromatic, from pour point ± 0 ° C 20

Polyethylene glycol (average molecular weight 4000) 1

Silanes, various quantities as indicated below

Nr.379404

Ingredients parts by weight

Tetramethylthiuram monosulfide 0.3

N-tert. Butyl 2-benzothiazyl sulfenamide 1

Sulfur 2.2

A comparison mixture produced therefrom contained no silane, another mixture contained 3.6 GT of the technical silane SO (see Example 2) and the two mixtures according to the invention contained 3.6 GT and 4.8 GT Cl-PTES, respectively (see Example 2) ).

Table V

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO • 3.6 GT</td><td colspan="2">with Cl-PTES</td>

<td>3.6 GT</td><td>4.8 GT</td>

<td>D. nm</td><td>0.75</td><td>0.71</td><td>0.65</td><td>0.67</td>

<td>ML 4</td><td>51</td><td>50</td><td>46</td><td>46</td>

<td>t 10%</td><td>11.5</td><td>9.8</td><td>12.3</td><td>12.0</td>

<td>t 80-t 20%</td><td>2.1</td><td>2.0</td><td>1.9</td><td>1.7</td>

<td>WW</td><td>20</td><td>18</td><td>24</td><td>24</td>

<td>SH</td><td>54</td><td>58</td><td>53</td><td>53</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>21.2</td><td>20.7</td><td>20.2</td><td>19.3</td>

Example 6: From the following compounding ingredients and amounts, four butyl rubber-based compounds were prepared and tested according to the method described above.

Components quantities in GT

Isoprene Isobutylene Rubber 100 active granulated silica filler (see Example 1) 50

Zinc oxide (see Example 4) 5

Stearic acid 1 naphthenic processing oil (see Example 4) 5

Polyethylene glycol (see Example 5) 3

Silanes, various quantities as indicated below

Tetramethylthiuram disulfide 2

Dipentamethylenethiuram tetrasulfide 1

Sulfur 1.7

Nr.379404

A comparative mixture was prepared without silane, a second with 6 GT of the silane SO (see Example 2) and two mixtures according to the invention with 6 or 8 GT of the silane Cl-PTES. The resulting test values ​​included the following.

Table VI

<td></td><td>without silane</td>

<td>D. m in</td><td>2.16</td>

<td>ML 4</td><td>112</td>

<td>t 10%</td><td>6.1</td>

<td>t 80-t 20%</td><td>17</td>

<td>WW</td><td>13</td>

<td>SH</td><td>64</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>34.1</td>

<td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>0.72</td><td>0.75</td><td>0.64</td>

<td>67</td><td>68</td><td>62</td>

<td>6.8</td><td>6.2</td><td>6.2</td>

<td>11.7</td><td>6.0</td><td>7.6</td>

<td>7</td><td>16</td><td>-</td>

<td>69</td><td>61</td><td>62</td>

<td>29.2</td><td>27.8</td><td>27.2</td>

Example 7: The following four blends based on butadiene-acrylonitrile rubber were prepared and tested in analogy to the preceding examples.

Ingredients quantities

Butadiene-acrylonitrile rubber with

34% acrylonitrile content and a

Mooney viscosity of 45 100 active, granulated silica filler (see Example 5) 50

Zinc oxide (see Example 2) 5

Stearic acid 1

Dioctyl phthalate 15

Silanes, various quantities as indicated below

Tetramethylthiuram disulfide 2.5

N-cyclohexyl-2-benzothiazolesulfenamide 1.5

The two comparative mixtures were again produced without Silanzusatz or with 6 GT of the silane of the prior art SO and the two mixtures according to the invention with 6 GT or 10 8 GT of silane Cl-PTES. Some selected, representative test results are included in the following table.

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Table VII

<td rowspan="2">without silane</td><td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>1.32 84 26 61</td><td>0.68 56 7 55</td><td>0.74 59 20 53</td><td>0.53 51 20 68</td>

Example 8: Based on styrene-butadiene rubber, the following four mixtures were prepared and tested analogously to the preceding examples.

Ingredients quantities

EPDM rubber 100 active granulated silica filler (see Example 5) 50

Zinc oxide (see Example 2) 3

Stearic acid 1

Processing oil, paraffinic 50

2,6-di-tert-butyl-4-methylphenol 1

Silanes, various quantities as indicated below

Di-2-benzothiazyl disulfide 1.5

Morpholine disulfide 1.5

Tetramethylthiuram disulfide 2.5

A comparison mixture was prepared without Silanzusatz, another with 6 GT of the silane SO and two mixtures according to the invention with 6 GT and 8 GT Cl-PTES (silane). Selected, representative test values ​​are listed in the following table.

Table VIII

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>D. min</td><td>1.04</td><td>0.57</td><td>0.56</td><td>0.51</td>

<td>ML 4</td><td>76</td><td>58</td><td>52</td><td>48</td>

<td>t 10%</td><td>4</td><td>4.9</td><td>5.1</td><td>5.2</td>

<td>t 80-t 20%</td><td>2.7</td><td>4.1</td><td>2.8</td><td>2.8</td>

<td>ZF</td><td>9.8</td><td>9.7</td><td>11.8</td><td>11.9</td>

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Table VIII (continued)

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 6 GT</td><td colspan="2">with Cl-PTES</td>

<td>6 GT</td><td>8 GT</td>

<td>ww</td><td>11</td><td>6</td><td>8th</td><td>8th</td>

<td>SH</td><td>53</td><td>56</td><td>51</td><td>50</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>26.9</td><td>10.7</td><td>9.9</td><td>10.4</td>

Among other things, the measured values ​​reveal improvements in mixture viscosities, tensile strengths, tear propagation resistance and shore hardness.

Example 9: Four mixtures based on styrene-5-butadiene rubber were prepared from the following ingredients as described above and tested according to the preceding examples.

Ingredients quantities

Styrene-butadiene rubber (SBR 1500) 100

Sound 80

Zinc oxide (see Example 2) 4

Stearic acid 2

Silanes, various quantities as indicated below

N-cyclohexyl-2-benzothiazolesulfenamide 1.5

Sulfur 2

A comparative mixture without Silanzusatz, a second mixture with 3 GT of the technical silane SO, and two mixtures of the invention were with 4 GT and 8 GT of the silane

Cl-PTES produced. The mixtures were tested in analogy to the preceding examples and gave the following values.

Table IX

<td rowspan="2"></td><td rowspan="2">without silane</td><td rowspan="2">with SO 3 GT</td><td colspan="2">with Cl-PTES</td>

<td>4 GT</td><td>8 GT</td>

<td>D.</td><td>0.88</td><td>0.94</td><td>0.79</td><td>0.77</td>

<td>mm</td><td></td><td></td><td></td><td></td>

<td>ML 4</td><td>75</td><td>79</td><td>69</td><td>67</td>

<td>WW</td><td>12</td><td>13</td><td>12</td><td>15</td>

Example 10: Oil-extended polybutadiene rubber is also amenable to the invention, as the following mixtures of the listed constituents show. The corresponding test results can be found in Table X.

Nr.379404

Ingredients quantities

Polybutadiene rubber oil-stretched with

37.5 GT oil per 100 parts rubber 137.5 active, granulated silica filler (see Example 1) 50

Zinc oxide (see Example 2) 4

Stearic acid 2

Silanes, various quantities as indicated below

N-tert. Butyl 2-benzothiazolesulfenamide 1.5

Sulfur 2

Table X

<td></td><td>without silane</td><td>with SO</td><td colspan="2">with Cl-PTES</td>

<td></td><td></td><td>6 GT</td><td></td><td></td>

<td></td><td></td><td></td><td>6 GT</td><td>8 GT</td>

<td>D. mm</td><td>2.48</td><td>1.14</td><td>1.16</td><td>1.01</td>

<td>SH</td><td>53</td><td>52</td><td>40</td><td>42</td>

Example 11 The mixtures of the following constituents show, when using further silanes which can be used according to the invention, that likewise valuable effects are achieved.

Ingredients quantities

Styrene-butadiene rubber (SBR 1500) 100 active granulated silica filler (see Example 1) 50

Zinc oxide (see Example 2) 4

Stearic acid 2

Silanes, various quantities as indicated below

N-cyclohexyl-2-benzothiazolesulfenamide 1.5

Sulfur 2

A comparative mixture was prepared without added silane. The mixtures according to the invention contained four different silanes in equimolar amounts (see Table XI, inter alia the silanes Α, B and C). The tests were carried out in analogy to the preceding examples. Some representative results are summarized in the following table.

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Table XI

<td colspan="2">without silane</td><td>Cl-PTES 7.5 GT</td><td>Silane A 6.2 GT</td><td>Silane B 7.6 GT</td><td>Silane C 7.9 GT</td>

<td>^D 120 '"^Dmin</td><td>6.9</td><td>11.2</td><td>10.8</td><td>12.9</td><td>8.0</td>

<td>ZF</td><td>15.8</td><td>19.7</td><td>20.0</td><td>20.7</td><td>18.3</td>

<td>M 300</td><td>3.4</td><td>8.8</td><td>8.9</td><td>15.3</td><td>4.6</td>

<td>BD</td><td>740</td><td>420</td><td>470</td><td>360</td><td>660</td>

<td>SH</td><td>62</td><td>67</td><td>69</td><td>73</td><td>64</td>

<td>A</td><td>172</td><td>103</td><td>97</td><td>75</td><td>163</td>

Silane A = chloropropyltrimethoxysilane

Silane B = bromopropyltrimethoxysilane and

Silane C = chlorobutyltriethoxysilane

In particular, this example shows the surprising fact that the otherwise often necessary additions of so-called secondary accelerators such as glycols and amino compounds become superfluous by the concomitant use of haloalkylalkoxysilanes. Compared to the comparative mixture, a so-called zero mixture, a significant increase in tensile strengths and Moduli 300 (stress value at 300% elongation) occurs. Shore hardness and elongation at break follow module values. Also, the abrasion is surprisingly considerably improved.

In general, the Cl-PTES causes a surprisingly high reduction in the mixture viscosities, as described in the D. Values ​​(150 ° C) as well as pressure in the ML 4 and MS 4 values. This valuable effect is more or less pronounced depending on the type of rubber or rubber compound, as it can be achieved by adding the silane according to the prior art, the SO.

Example 12: The following blends based on styrene butadiene rubber (SBR 1502) are practice blends for the production of transparent shoe soles.

Ingredients quantities

SBR 1502 100

Zinc oxide (see Example 2) 3

Stearic acid 1

Mixture of aralkylated phenols (see Example 4) 1

Salicylic Acid 0.8 Active Granulated Silica Filler (see Example 1) 50

Silane amounts like

Zinc 2-mercaptobenzothiazole indicated below 1,75 '

Nr.379404

Ingredients quantities

Diphenylguanidine 1.75

Hexamethylenetetramine, granulated (containing 3% by weight of silica filler) 1

Sulfur 2

A comparative mixture contained no silane additive. The mixtures according to the invention contained 5 GT or 7.5 GT Cl-PTES (see Example 2), and the addition of silane was advantageously carried out immediately after the addition of X rubber into the mixer together with the first half of the silica filler. The temperature at the beginning of the first mixing phase was chosen at 80 ° C; at the beginning of the second mixing phase (after 24 hours of intermediate storage) it was 50 ° C. Otherwise the preparation and tests of the mixtures were carried out as described above (rheometer test at 150 ° C.).

Table XII

<td rowspan="2"></td><td rowspan="2">without silane additives</td><td colspan="2">with Cl-PTES</td>

<td>5 GT</td><td>7.5 GT</td>

<td>D. mm</td><td>1.26</td><td>1.21</td><td>1.14</td>

<td>D Max</td><td>11.75</td><td>13.12</td><td>13.47</td>

<td>D -D. max min</td><td>10.49</td><td>11.91</td><td>12.33</td>

<td>t 95%</td><td>11.7</td><td>16.0</td><td>27.9</td>

<td>t 90-t 10%</td><td>5.1</td><td>8.6</td><td>14.1</td>

<td>θmax (ji ax + 60 ') ^</td><td rowspan="2">5.1</td><td rowspan="2">1.9</td><td rowspan="2">0.3</td>

<td>D -D. max mm</td>

<td>ML 4</td><td>104</td><td>101</td><td>96</td>

<td>t 5</td><td>3.1</td><td>2.8</td><td>1.6</td>

<td>t 35</td><td>4.0</td><td>3.7</td><td>2.4</td>

<td>ZF</td><td>10.2</td><td>12.7</td><td>-</td>

<td>M 300</td><td>4.4</td><td>6.5</td><td>7.7</td>

<td>SH</td><td>62</td><td>69</td><td>70</td>

<td>A</td><td>114</td><td>108</td><td>110</td>

¹ The value of this fraction is called reversion and measured in percent

It can be seen from the test values ​​as results to be emphasized that the addition of silane leads to decreasing viscosities, to reduced vulcanization rate and to less reversion. 0.3% means a virtually non-reversible mixture or a non-reversible

- 23 Nr.379404

Vulcanized. For explanation, it is added that the value D (_n._{ax +}60 ') d^as3^eniS^e Torque is measured at the time 60 min after the maximum torque has been applied. The vulcanizates show significant increases in the values ​​of moduli, Shore hardness and abrasion.

Example 13: The following mixtures contain a mixture of two different types of rubber, a halogen-free and a halogen-containing rubber.

Ingredients quantities

Styrene butadiene rubber (SBR 1500) 60

Polychloro-butadiene rubber (chlorine content about 38%, viscosity 40 to 45 Mooney units) 40

Silica filler (see Example 1) 50

Magnesium oxide 2

Stearic acid 2

Silane as indicated below

Zinc oxide (see Examples 1 and 4) 5

N-cyclohexyl-2-benzothiazolesulfenamide 1

Sulfur 2

As silane, the mixture according to the invention (E 13) contained 7.5 parts by weight of purified, distilled Cl-PTES. The comparison mixture (V 13) was a so-called zero mixture. The preparation and the tests of the mixtures were carried out in analogy to the preceding examples.

Table XIII

<td rowspan="2">exam</td><td colspan="2">mixture</td>

<td>V 13</td><td>E 13</td>

<td>ML 4 (100 ° C)</td><td>155</td><td>121</td>

<td>D. mm _s</td><td>2.86</td><td>1.64</td>

<td>ZF</td><td>10.9</td><td>16.1</td>

<td>M 200</td><td>3.7</td><td>5.6</td>

<td>M 300</td><td>6.0</td><td>9.8</td>

<td>A</td><td>171</td><td>116</td>

<td>CS (22 h, 70 ° C, unaged)</td><td>12.1</td><td>8.6</td>

The addition of chloropropyltriethoxysilane greatly reduces the Mooney viscosity, resulting in better processability, while improving the vulcanizate's static properties: higher tensile strength, higher moduli, higher abrasion resistance and lower (better) compression set. The advantages of the mixture according to the invention with the comparatively simple structure and preparation of chlorosilane and the vulcanizate thereof are obvious.

Example 14: The following blends based on styrene-butadiene rubber (SBR 1500) 5 provide evidence of advantageous use of premixes of silane and filler with synergistic effects.

<td rowspan="2">ingredients</td><td colspan="6">Mixture no. (Quantities in GT)</td>

<td>V 14.1</td><td>E 14.1</td><td>V 14.2</td><td>E 14.2</td><td>E 14.3</td><td>E 14.4</td>

<td>SBR 1500</td><td>100</td><td>100</td><td>100</td><td>100</td><td>100</td><td>100</td>

<td>Zinc oxide (see Example 1)</td><td>4</td><td>4</td><td>4</td><td>4</td><td>4</td><td>4</td>

<td>stearic acid</td><td>2</td><td>2</td><td>2</td><td>2</td><td>2</td><td>2</td>

<td>Silica filler (see Example 1)</td><td>50</td><td>50</td><td>50</td><td>50</td><td>50</td><td>42.5</td>

<td>HAF carbon black N 330</td><td>-</td><td>-</td><td>7.5</td><td>7.5</td><td>-</td><td>-</td>

<td>Cl-PTES, cleaned with ammonia</td><td></td><td>7.5</td><td></td><td>7.5</td><td>-</td><td></td>

<td>premix Carbon black / Cl PTES¹)</td><td></td><td></td><td></td><td></td><td>15</td><td></td>

<td>premix Silica filler / Cl PTES²¹</td><td></td><td></td><td></td><td></td><td></td><td>15</td>

<td>N-cyclohexyl-2-benzo- thiazolsulfenamid</td><td>1.5</td><td>1.5</td><td>1.5</td><td>1.5</td><td>1.5</td><td>1.5</td>

<td>sulfur</td><td>2</td><td>2</td><td>2</td><td>2</td><td>2</td><td>2</td>

1: 1 mixture of HAF soot, in powder form (BET surface area 78 m²/G; average primary particle size 27 nm) and Cl-PTES

2)

1: 1 mixture of silica filler (according to Example 1) and Cl-PTES

The preparation and testing of the six mixtures, of which four according to the invention (E 14.1 to E 14.4) were carried out in analogy to the preceding examples. The relevant test results are summarized in the following table (vulcanization temperature = 160 ° C).

Table XIV

<td></td><td>V 14.1</td><td>E 14.1</td><td>V 14.2</td><td>E 14.3</td><td>E 14.4</td><td>E 14.4</td>

<td>vulcanization</td><td>85</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td>

<td>ZF</td><td>16.2</td><td>18.7</td><td>18.5</td><td>16.2</td><td>17.7</td><td>17.7</td>

<td>M 200</td><td>2.5</td><td>5.9</td><td>3.5</td><td>5.1</td><td>6.1</td><td>7.0</td>

<td>M 300</td><td>4.5</td><td>11.3</td><td>6.2</td><td>10.4</td><td>12.2</td><td>13.9</td>

<td>BD</td><td>620</td><td>390</td><td>550</td><td>340</td><td>370</td><td>340</td>

Nr.379404

Table XIV (continued)

<td></td><td>V 14.1</td><td>E 14.1</td><td>V 14.2</td><td>E 14.2</td><td>E 14.3</td><td>E 14.4</td>

<td>SH</td><td>62</td><td>69</td><td>70</td><td>72</td><td>72</td><td>69</td>

<td>A</td><td>133</td><td>91</td><td>118</td><td>93</td><td>91</td><td>91</td>

<td>Rheometer test D. min</td><td>1.90</td><td>1.36</td><td>2.37</td><td>1.42</td><td>1.52</td><td>1.58</td>

<td>^D120 '</td><td>8.49</td><td>12.53</td><td>10.07</td><td>13.47</td><td>13.88</td><td>12.38</td>

<td>° 120 ' ^-Dmin</td><td>6.58</td><td>11.18</td><td>7.70</td><td>12.05</td><td>12.36</td><td>10,80</td>

<td>η - π 120 ' ^u60 '</td><td>16.5</td><td>8.2</td><td>11.1</td><td>6.5</td><td>7.7</td><td>10.3</td>

<td>° 120 '"^D min Mooney test ML 4 (100 ° C)</td><td>155</td><td>122</td><td>172</td><td>124</td><td>127</td><td>132</td>

<td>t₅ (130 ° C)</td><td>&gt; 70</td><td>83.7</td><td>60.0</td><td>61.7</td><td>64.1</td><td>86.4</td>

The numbers of the test results show the following: By adding 7.5 parts by weight of 3-chloropropyltriethoxysilane to the comparative or zero mixture V 14.1, the following improvements are achieved: increase in tensile strength, pronounced increase in moduli and Shore hardness and improved abrasion ( E 14.1). As expected, minor improvements in the properties of the vulcanizates also result from the addition of carbon black, and the rheometer values ​​also improve somewhat, whereas the Mooney viscosity is also expected to be degraded (V 14.2, compared to V 14.1). , Now the silane is added (s. 14.2, compared with V 14.2), so come back to the invention, desirable, sometimes very lent refinements, only the tensile strength is an exception.

If, however, the premixes are used instead of the separate individual additions, then usually further improvements of the moduli and the crosslink density occur, u.zw. in both the black and the white mix. These synergistic effects were confirmed after storage of the premixes for two months, indicating good storage stability

Indicates premixes.