DE1470902A1 - Process for the manufacture and retreading of tires - Google Patents

Description

£? Pnt eca t ini_ Speieta. GeneraI. jcer. 1_'Industria_ Minerar.ia_ e Chimica.j_Largp_ G _._ pcneganij_ i-2 ^ _ Milan_ j Italy} ^

Process for manufacturing and tread renewal

of tires.

The invention relates to a process for the manufacture or tread renewal of tires of mixed construction, where the carcass is made of natural rubber or synthetic diene rubber, while the tread is made of a saturated copolyesters of ethylene with an α-olefin or a terpolymer of ethylene with an α-olefin and a non-conjugated diene.

Natural rubber, the first elastomeric product to be used in tire manufacture, has excellent general properties, especially the lowest elastic hysteresis among technical rubbers, but low abrasion resistance (which can, however, be improved by using suitable fillers) and low aging resistance, which is caused in particular by the attack of ozone. Various attempts have been made to replace some or all of natural rubber with synthetic rubber types which have more properties in this regard, e.g. through SBR rubber and butyl rubber ',' **

Elastomers, 'old are highly saturated and therefore; an ay '* · ^ SI 8onde> ^ 1w $ e ^ have been resistant to oxidation since

For some time the anti-reporter must have been produced. They consist of j

from copolymers of ethylene with propylene or Euten- 'and are prepared by copolymerization of mixtures of the Koncmeren in the presence of catalyst systems: s by reaction of transition metal compounds, instesonde re vanadium compounds, with organometallic compounds, especially aluminum trialkyls and aluminum alkyl halides. can be obtained. These copolymers can 01efinen a-of ethylene with known using peroxide compounds which form free radicals, in the presence of an acceptor, such as sulfur, at temperatures between 140 and '8Q ⁰ C werden- vulcanized These copolymers now commonly used in the art and the with you . The vulcanized products obtained are characterized by very good mechanical properties, excellent wear resistance and aging resistance and sufficiently low hysteresis (which, however, is higher than that of natural rubber). Because of these properties, they are suitable for the production of tire treads, which clearly have better properties as running surfaces made of common types of rubber

The copolymers mentioned can also be used for the complete manufacture of tires, but is preferred Natural rubber or a synthetic rubber with lower Hyatcicco used for the tire parts that are subject to greater bending stresses, namely for the sides and the carcass »

Furthermore, weakly unsaturated elastomers are known which consist of products which are obtained by statistical copolymerization of ethylene with propylene and a smaller amount of a non-conjugated bene, in particular a linear diem, such as 2-methylpentadiene-1,4, 11-ethyl-trieta <i | en-1 ₃ 11, 6-methylheptadiene-1,5 etc., and one non-conjugated "> cyclic dienes, such as bicyclo (2.2,1) heptaflien-2 _s : 5, L} icy .. · - pentadiene, vinylcyclohexene, cyclooctadi n - 1.5 v.sw. '. erhe ^Ί -' ir

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«These terpolymers can be used with the same catalyst systems as for the production of the copolymers are produced and contain double bonds in the macromolecules, which randomly benefits in the side groups and allow vulcanization with sulfur and ultra-accelerators of the type used for Eutyö rubber Like the copolyraeren, these terpolymers can be vulcanized with organic peroxides and auxiliaries such as sulfur will"

The vulcanized products obtained with these terpolymers are also characterized by very good mechanical * elastic and electrical properties and an exceptional resistance to oxidation and chemicals and are therefore suitable for many applications, both in the field of conventional rubber types and in the field of special rubbers, in particular for the manufacture or tread renewal of tires o one Carcass made of natural rubber and a tread made of a copolymer of ethylene with an α-olefin or a Terpolymers of ethylene with one α-olefin and one not conjugated diene represent a very good combination for the production or tread renewal, as it is based on this way it is possible to combine the bedding properties in a single product. This manufacture cdcr Tread renewal of tires is known to be made more difficult by the fact that natural rubber with the aforementioned ' Types of elastomers is not compatible, so that it was not possible to directly glue the layers together of the two incompatible rubber types during their mixed vulcanization »

It is known that natural rubber can be vulcanized with organic peroxides, but mixtures of Natural rubber with the copolymer or terpolymer. both of which contain organic peroxide after vulcanization

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insufficient adhesion, the same is true for mixtures of natural rubber and terpolymeres of ethylene with propylene and non-conjugated dienes of the pallet ₅ which contain vulcanization systems based on sulfur "

A solution of this problem was that was placed a third layer between the two layers _v consisting of a chemically modified ethylene-oc-olefin copolymer, which was physically and chemically compatible with two types of rubber and with the! Respective vulcanization This The third layer consisted in particular of a chlorosulfonated copolymer of ethylene with an ot-olefin. · This method made it possible to achieve the desired purpose, but it complicated tire production and was associated with higher costs "

Another method which enables complete compatibility and adhesion between the layer of natural rubber and the layer of the copolymer is to use a very specific vulcanization mixture which is enriched with peroxide and sulfur, and a vulcanization temperature of more than 70 ⁰ C. This high temperature cannot, however, always be reached with the machines used in the rubber industry. Furthermore, the higher amount of peroxide and sulfur increases the unpleasant odor that these vulcanizing agents often have. To avoid these disadvantages, it was necessary to use the mixture with a modified vulcanization recipe in the form of a thin sheet on which a third layer from which the copolymer was applied with the same recipe »This method also has the disadvantages of using an intermediate layer»

The invention is a Mischvulkanisationsver- go for. Manufacture of tires whose carcass is on

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Natural rubber or an unsaturated synthetic rubber based and whose tread is based on a copolymer of ethylene with an α-olefin or a T-polymer des Ethylene with one ot-olefin and one non-conjugated Based on diene, it is possible to bond these two layers directly to different elastomers to be achieved without the use of an intermediate layer or an adhesive layer. The invention also encompasses tires Mixed construction, consisting of a carcass based on a diene rubber and a tread on the Based on saturated copolyraercn or weakly unsaturated terpolymers, which are directly connected to the carcass is c

It has been found that when using copolymers or terpolymers based on ethylene and propylene or Euten-1, which have a Mooney viscosity ML (ir4) of 60 or more than 6Q at 'QQ ⁰ C, it is possible without special precautionary measures complete compatibility or adhesion between a natural rubber layer, which contains a light reinforcement, f8ästoff and vulcanizing agent based on sulfur and accelerators, and a layer of the mentioned elastomers !! Copolymers or ferpolymers, which contain an organic poroxide and sulfur as vulcanizing agents, _t

The process according to the invention for the production and renewal of tires with a mixed structure is characterized in that the connection between the two layers of different types of rubber during mixed vulcanization is achieved by using one layer of saturated ethylene-α-olefin copolymer or a weak one unsaturated terpolymer, which consists of ethylene, propylene and a non-conjugated dieig, and has an i ^ onty viscosity IiL (1 + 4) of _{-6O 1} OdJy pohr at 100 ⁰ O hfti and an organic peroxide and sulfur as

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Contains vulcanizing agent, directly on a layer from a natural rubber or synthetic diene rubber, which contains a white pulp and vulcanizing agent on the basis of sulfur and accelerators, and then carries out the mixed vulcanization,

Very high adhesion values are achieved - those in heat. for example, are still not satisfactory at 9O ⁰ C, / are namely at the peeling tests according ASTlI E-4'3 39 10-'2 kg / cm.

Particularly good results are achieved in the method according to the invention when synthetic rubber is used instead of natural rubber Diene rubbers, ζ B = styrene-ethylene copolymers: cis-1,4-polybutadiene, cis- '; , 4-polyisoprene, butyl rubber, Nitrile rubber etc. are used v / ground. The usage of However, natural rubber is preferable for the reasons mentioned above »

Good adhesion values are also achieved if the elastomer Copolymers or terpolymers with high Mooney viscosity calibrated to reduce its viscosity to the desired values and to improve processability, That is, it is stretched with paraffinic oils * For example, a copolymer with a Hooney viscosity of 80 whitened with 30 parts per 100 parts of a paraffinic oil to bring that down to 1IL 25, " Adhesion values on natural rubber (under otherwise identical curing conditions), which are much higher than an unstretched copolymer of the same viscosity ML 25c

These direct connection results are very surprising and unexpected given the use of copolymers with high Mooney viscosity due to their poor. Processability in normal machines (mixing mills, Mixer, - extrusion) was avoided from the start. Experience has also shown that when using Copolymers or torpolymers which are produced in this way

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that they are sufficient or easily processable was not possible, acceptable adhesion values with natural rubber and the other diene rubbers, as these are copolymers and terpolymers, the ethylene and propylene do not have the possibility of reducing their Mooney viscosity through hastication. An instant one Separation of the layers took place particularly in the heat

The results of the direct adhesion according to the invention are also used with weakly unsaturated elastomeric terpolymers based on ethylene, propylene and non-conjugated dienes surprising and unexpected, as they are known just like butyl rubber can hardly be mixed vulcanized with natural rubber.

Furthermore, it was not to be expected that an elastomer with a high Mooney viscosity (^ H6O) can retain its good adhesive properties even when it is stretched with paraffinic oils until a lower Mooney viscosity, which is better for the processing of this elastomer. r is achieved. As already mentioned, this adhesion of the plasticized elastomer with low Mooney viscosity (adhesion expressed as the peel strength value) is much higher than for a corresponding non-plasticized elastomer which is produced from the outset with the same low Mooney viscosity as the plasticized elastomer .

Among the light-colored mineral fillers that are used to reinforce natural rubber or synthetic diene rubber Used include anhydrous and hydrated silica. Particularly good adhesion values are achieved if the mixture is based on natural rubber 20-100 parts by weight of light mineral filler per Contains 100 parts of natural rubber

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If the mixture is based on natural rubber a black reinforcing filler. ζ Β Furnace- ^ Channel-. Contains thermal soot, etc., the adhesive values are clear lower, if no fillers are present in the natural rubber layer, no connection will be made with the Layer obtained from the copolymer or terpolymer *

The method according to the invention for combining the two rubber layers is of particular interest because of the exceptional adhesion values in the heat exhibited by the vulcanizates. It is to be noted that it was not possible in the case of the known synthetic rubbers to obtain words for adhesion to natural rubber (Schälmethcde) at 9O ⁰ C, the 14-'5 kg / cm and at brominated with butadiene-styrene copolymers Butyl rubber (isobutylene-isoprene copolymers are above 8-10 kg / cm.

For the purposes of the invention, the copolymers used are preferably those of ethylene with α-olefins, in particular with propylene and / or butene- 'whose ethylene content is between 20 and 80 LTol-fS, preferably between 40 and 65 Uol-fo , and their Llooney viscosity HL ⁽ ">'--A-)at' IUO ⁰ C has a value of 6ü or more than 60, ζ B- between 60 and '.00

The terpolymers used according to the invention on the basis of ethylene and propylene, as a third co "monomeric a non-conjugated, linear or cyclic diene, in particular dicyclopentadiene or cyclooctadiene-i ₉ O in such amounts that _0; 03 to '/ double bond per is '00 carbon atoms are present. the Äthylcngehait must lie between 20 and 80 Uol-fo, and the terpolymer must have a Mooney viscosity MI (144) of 60 or greater at 100 ⁰ C.

The blends of the copolymer and terpolymer generally contain a reinforcing filler in an amount of from 5 to 200 parts, preferably from 20 to 100 parts, per 009808/1557

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'OO parts of the copolyraeren or terpolymer

The vulcanizing agent used in the mixtures of the copolymer or terpolymer is an organic peroxide in an amount of 0.1 parts by weight per 100 parts by weight of copolymer or terpolymer and sulfur in an amount of less than 50% of the amount of peroxide When vulcanizing agents are used based on sulfur and accelerators under soii3t unchanged working conditions in the mixture of Terpolyracren, the adhesive strength of Terpolyraeren achieved on natural rubber satisfactory values. the Vulkanisationsteinperatur between Ό and 200 ^c C, preferably between "! 40, and ' 80 ⁰ C

The invention is illustrated by the following examples, although only the use of ethylene-propylene copolyraeren and of ethylene-propylene-cyeicc ^ tadiene terpolymers are described, but equally good results have also been obtained with copolymers of ethylene with butene with terpolymers of ethylene and propylene and non-conjugated dienes which are different from Cyclcectadiene- ', 5 , e.g., dicyclopentadiene, Eexadiene-: ö and the like.

The adhesion values mentioned in the examples were determined according to the ASTK-r-413/39 method, the scg. Schäiraethcde, determined and are given in kg / era. The test specimens for determining the adhesion values were produced as follows: The mixtures to be bonded are processed into 3 mm thick sheets on the mixing roll mill. Rectangular pieces measuring 16 8 cm are cut out and, after their surface has been treated with a solvent such as heptane, benzene, etc., are placed one on top of the other. The vulcanization takes place in a press. In order to be able to carry out the peel test better, the test specimens are reinforced by applying them to the outside of square pieces of fabric before pressing. From the vulcanized

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Plate were 3 specimens with a width of 2 cm with a Hole punch cut out

In some commercial tires, the tread made of natural rubber has been replaced by a tread made of an ethylene-propylene copolymer with a Hooney viscosity ML '/' M, of 6 ° at '.QO ⁰ C and with a paraffinic oil (FL 65 ) vcn relative / 5; been · $ Ccpolvme · risat to 25 ^ oil extended was the bonding of the tread from the ethylene-propylene copolymer ao with ^s? The carcass made of vulcanized KaturkautcDhuk was made as follows: A commercially available adhesive on chewing: hukba3is, as it is customarily used for the treads; used by tires, was applied to the roughened carcass A thin layer of natural rubber of the following composition was then applied to the carcass:
Mixture A_

Ibasticised rubber (Llooncy Vislrciität KL ('. -4 / at' CQ ^C C - 40 i 'üO parts

Antioxidant (Pheny1-ß-naphthylamine) ■ "

Anhydrous silica (Aerosil. 40 "

ZnO 5 »

Diphenylguanidine Q. 5 »

Santocure (Oyclohexyl * «benzothiazyl-sulphen ~ i 2" sulfur ^{aa ± d)} 2 _? 5 »

A maturing mixture based on an ethylene-propylene copolymer of the following composition is then applied to this thin layer:

M ischu ng B

Ethylene-propylene copolymer (propylene content 50 Κο1-5έ _Γ Mooney viscosity ISL (I + 4 / at 100 ⁰ C = 60 75 parts

oil PL 65 25 »

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HA? Carbon black 50 parts

JJchv / elc: Ü- ': "

f <. α ¹ -BIj, 't-fcutylpercxy dii; 3opropyibenzol 3-'2 "(Per c: <iir.cn

The thus constructed tire be in a suitable form for 50 minutes at a temperature of '' ~ O ^C C .ulknnioiert the and provided to serve way with new treads a "road wheel" ιοί ^(? 0 Kia / h with a load Tires tested by 6CO kg / axle behave like the corresponding commercial tires with new treads based on natural rubber Ethylene-propylene copolymers found.

A tire was made with a carcass made of natural rubber and a tread made of an ethylene-propylene copolymer

I.iL i ': 4, at 100 ° C = 6j';, that with a paraffinic oil. in a ratio of Τ3; "ί Copclymerisat 'to 2lffS Oi was prepared. The union between the carcass made of natural rubber and the tread made of the ethylene-propylene copolymer was prepared with the help of a'. mm thick intermediate layer of white natural rubber to the composition of the mixture Λ in example «had» This tire, which was tested on the road bike at 60 km / h and under a load of 600 kg / axle, showed no difference between the natural rubber and the ethylene-propylene copolymer used for The mixture used for gumming the intermediate layer had the following composition: Natural rubber (LlL (1 -f-4 ** at 100 ^C C = 40; 100 parts ZnJ ί Ii

? RF-Euß 25 "'

Phenyl-ß ~ naphthylamine -, "

Stearic acid 1 "

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Pine tar 5 parts

Di-o-toly! Guanidine 0.75 "

Santccure 0, "5V

Sulfur 2.8 "

The tire mixture based on the ethylene-propylene copolymer had the same composition as the mixture B according to example 1.

a} Two mixtures of the following composition were made

manufactured:
Mix ng A

Natural rubber (raastisiert up to HL (1- * 4)

at 100 ° E = 40> 100 parts Antioxidant 1 "

Anhydrous silica (Aerosil) 40 "

ZnO 5 °

Diphenylguanidine 0.5 "

Santo eure ',, 2 "

Sulfur 2.5 »

Mi s_ch_u rij g B

Ethylene-propylene copolymer (propylene content 45 ΙΖοΙ - ', Ό, Mooney viscosity LJL

(1 + 4) at 100 ⁰ C = 60 100 parts

HAF carbon black 50 H

Sulfur 0.3 "

α, α'-bis (t-butylpercxy ) diisopropylbenzene

(Paroximony) '1.6 "

The specimens were formed in a press for 50 minutes at 160 ⁰ C = the peel test the body was carried out at 25 and 90 ⁰ C "following Ergebnisoe were obtained:

At 25 ⁰ C 16 kg / cm

At 90 ⁰ C 12 kg / cm

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"b) the adhesion of the mixture was screened Λ eat the following mixture For comparison Ä'thylen-propylene Copolyraerisat (propylene content 48 # piston, Mooney viscosity ML (1 + 4) at 100 ⁰ C - 20) 100 parts

HAF carbon black 50 "

Schcfol 0.3 "

_α , a'-bis (t-butylperoxy) diisopropylbenzene (Peroxiraon) 1 ₅ 6 »

The conditions of the vulcanization and the peel test were the same as specified under a) "For the peel tests the following results were obtained:

At 25 ⁰ C 6 kg / cm

At 90 ⁰ C 2 kg / cm

The adhesion values of this mixture are based on the copolymer with the Kooney viscosity of 20 are significantly lower than the aforementioned mixture based on a 'Copolymers with a Kooney viscosity of 60 »

Example 4_

This example illustrates the influence of the Mooney viscosity of the ethylene-propylene copolymers at 100 ⁰ O. the adhesive values when combined with natural rubber. Mixture A according to example 3 is pre-glued with mixtures of type B according to example 3, parts are produced with different copolymers and have the Mooney viscosity indicated in table 1. The copolymers used had a propylene content of 45-55 K0I-5 &. The vulcanization times and temperatures are the same as in Example 3.

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Table 1 Peel strength in kg / c
at 25 ⁰ C at 90 ⁰ C 2 Kocney viscosity KL (144)
of ethylene propylene copoly-
mer at 100 ° C 6th 3 13th 9 5
8th 28 10 12th 36
40 '7 U 61 17th 14th 80 16 -5 100 "8th 140

Example 5

This example illustrates the adverse influence of the plasticizer type for the ethylene-propylene copolymer on the adhesive value ara natural rubber, v / enn da3 copolymers has the required high Ifooney viscosity «.

An ethylene-propylene copolymer? DAT to that described in Example 1 is identical (Kooney viscosity ML (1-My at 100 ⁰ C = 60), it is with those indicated in! Table 2 plasticizers in a ratio of 75 parts Copolynierisat to 25 The resulting mixtures are bonded with the mixture A based on natural rubber according to Example 3.

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Table 2 Plasticizers Sohäl f * ersti / Skeitj kfj / oin at 25 ⁰ C at 9O ⁰ C Polypropylene adipate (Exaplas PPA) 13th 10 Mineral oil (viscosity Schv / eie constant = 0.82) H 8th Eutyl stearate H 11 Caphthenic oil (Circosol 2xH, kinematic

Toughness at 99 ⁰ C = 1? cSt,

Viscosity ~ gravity constant

0.885) 16 11

Paraffinic oil "Fl 65"

(Viscosity at 50 ⁰ C = 2.2 °

Engler, Viscosity Schv / ere-

Constant = 0.80 '8 14

In all cases, the stretched product showed good adhesion values in connection with natural rubbers

This example illustrates the influence of the filler in the natural rubber-based mixture on the adhesion values in connection with the mixture B according to Example 3 * Die Mixtures based on natural rubber have the composition of mixture A according to Example 3, but with the fillers listed in Table 3 are used on Aercsil studs «,

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50 minutes in the press at 160 ⁰ C Fü 11 st ο ff

at. 25 ° C_ MLiLQU

Anhydrous silica

(Aerosil) 24 16

Hydrated silica

(Hi-SiI) 2-1-16

Hydrated silica
(Santocel) .24 16

HAP carbon black 10 2 _r 5

The best values are obtained with white acid-type fillers

Be ± 3jp ± el _m 7

This example illustrates the influence of the amount of paraffinic plasticizer (mineral oil PL 65) in the ethylene-propylene copolymer on the adhesion value in connection with mixture A according to example 3 - The mixtures based on the copolymer have the composition of mixture B according to example 3 » In the following tables the results of some tests are compiled which are carried out with a copolymer which had a Kocney viscosity of 150, 100, 60 and 30 at 100 ° C. and a propylene content between 45 and 55 mol. Pressing conditions: 15 minutes at 16O ⁰ C.

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Table 4 Peelings, kg / cm
at 25 ⁰ C at 90 ⁰ C 15th Ethylene
Propylene
Copolymer
(Kooney visc-
sity ML (I -! 4)
at '.0O ⁰ C = I50),
Parts by weight More paraffinic
Plasticizers
(Oil PL 65) r
Gexic parts 20th 16 100 - * 9 15th 95 5 20th 15th 90 10 18th 17th 85 1.5 19th 14th 80 20th 18th 16 75 25th 18th 17th 70 30th 16 t5 65 35 -.8th- H 60 40 16 15th 55 45 15th 15th 50 50 '18 6th 45 55 ■ '6 6th 40 60 12th 35 65

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Table 5

Ethylene-Propylene-Oopolymercs
(Mooney viscosity ML ('-: 4)
at .0O ⁰ C = 100

Paraffinic peeling festival. kg / cm plasticizer ~ "" ₀ "~ " _, "'_ c7 (oil FL 65)

6e \ v = parts at 25 ^C C

at 90 C

00 - 18th 95 5 19th 90 10 17th 85 15th 16 80 20th 18th 75 25th ι Ο 70 30th "7 65 35 18th 60 40 18th 55 45 15th 50 50 14th 45 55 10

■ 5 Io

'• 5

5 -

■ P

8 5 4

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Ethylene More paraffinic VJl Peel strength; . kg / cm Propylene
Copolymer
(Hooney visc-
sitat MLi-M)
at 100 ° C = 6Q)
Parts by weight Uc i china rather
(Oil PL 65)
Parts by weight :O at 25 ⁰ C at 9 O ⁰ C 100 - 15th '8th -5 95 20th '9 14th 9 * 0 25th Vl 15th 85 30th .6 16 80 35 17th VJl 75 40 18th H 70 45 16 10 65 50 '4 8th 60 '2 4th 55 10 3 50 -,O 2

Table- 7

Ethylene-Paraffinic ^ hälfe_s_t_igke_i_b_j ^ kg / cm

Propylene plasticizer, ~. ~~ "o ~ ""ο

Copolymer (oil PL 65) ^{at 2} ^ ° ^tei 90 C

(Kooney viscose parts by weight

sity ML (Vi 4)

at; 00 ° C = 30)

Gew »-part 3

- 10 3

95 5 7 2

90 IQ 8 2

85 15 6 2

80 20 6 1.2

75 25 6 1.5

70 30 5 1.1

65 35 5 1

60 40 4 1

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From the values in these tables it can be seen that the Copolymers at any Mooney viscosity allows a certain stretching with oil up to a limit value, above whose adhesive value drops quickly ο With Copol.yraeren with a Mooney viscosity of 30 are the adhesion values always low

The adhesive strength of terpolymers of ethylene with propylene and cyclooctadiene- ':. ρ in varying quantitative ratio of the mixture Λ based on natural rubber of Example 1 was found The terpolymer used had untercchiedliche Kooney viscosity and · different molar compositions ₀ The mixtures on the basis of the terpolymers were either treated with sulfur and accelerators or with sulfur and peroxides vulcanized.

a) Vulcanization of the terpolymer with sulfur and accelerators (comparative example) "

The mixtures based on the terpolymer had the following

Composition5

Ethylene-propylene-cyclocctadiene-1,5-terpolymer

ZnO

HAP soot

Stearic acid

Phenyl-ß-naphthylamine tetramethylthiuram disulfide Mercaptobenzothiazyl sulfide sulfur

The test specimens were held in a press for 40 minutes at 155 C = The results of the peel tests are given in Table 8.

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100 Parts H 50 I! 0.'5 η 1 Il 1 Il O ₅ 5 W. 2 It

Tabj3lle_ 8th Unsaturated
Ties
(Cyclcocta-
dien-'i .5) Peel
kg / cm activity; Mooney Visc
sity UL (I +4) Molar composition 3 at 25 ⁰ C at 9O ^C 3 of the copolymer
at -; οο ° σ Propylene
Kol-jfc 3.5 Ό 0 35 50 2.9 0 0 45 57 3.2 0 0 60 3.7 2.5 0.5 100 55 6.5 4.2 HO 50

The above values show that in the case of vulcanization mixtures which do not contain any peroxide, no satisfactory values are achieved.

b) Vulcanization of the terpolymer with sulfur and peroxide O

These mixtures based on the serpolymer have the following composition:
Ethylene-Propylene-Cyciccctadiene-1,5-Copolymer 100 parts

ZnO 3 Il HAF carbon black 50 Il Antioxidant ("Plectol H") 0.5 Il Pine tar 0.5 Il sulfur 0.63 Il _α , α'-bis (t-butylperGxy) diisopropylbenzene ("Perc: cimon") -, 7 Il

The test specimens were held ^{at 165 0} O in a press for 40 minutes

The results of the peel tests are given in Table 9 « ,

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Tab 11 e_ £

liooney visc- molar composition peel strength, sity IiI (I-! 4). Jc £ _ / cm

dea copolymers FropyTen Unsaturated

at '.CO ⁰ C UoI-Ji bonds at 25 O at 90

(Cyclcccta-

35 50 3 7.2 4.5 45 57 3.5 8.3 5 60 63 2.9 14th ·; Ο 100 55 3.2 -.6 12th 140 50 3.7 16 13th

The vulcanization recipe containing peroxide is used in Bonding with natural rubber achieves adhesive strength. that at a Kooney viscosity of 60 also in this case satisfactory values achieved "

The adhesive strength of ethylene-propylene copolyraeren. which was vulcanized with peroxides, on natural rubber which was vulcanized with sulfur and accelerators, in both cases no fillers were used, was determined »Copolymers of different Mooney viscosity, namely 30, 45, 60, 100 and 140, were used, the mixtures based on the copolymers and based on natural rubber had the following composition: mixed A ung
Natural rubber (Ul (I + 4) at 100 ^° C. = 100 parts

Antioxidant 2246 (2.2 <-Kethylene-bis- (4-niethyi-

6-t-bu ty ! Phenol) . 1 "

ZnQ ■ - .. 3 η

XldLphenylguanidine 0.5 - ⁿ

Santocure 1.2 "

Sulfur 2.5 »

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Ethylene-propylene copolymer '00 parts

Sulfur 0.3 "α. Α '-Bis', ΐ-fcutylpercxy' diiscprcpyibenzol

("Percximcn ¹¹ ; VT"

The test specimens were in a press for 40 minutes at: 65 ° 0 held

In all cases the adhesion value is zero. From this it can be seen that the Λην / esenaeit of at least one carbon black or preferably a light mineral filler in the mixture based on natural rubber is necessary _{: in} order to achieve adhesion ..

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Claims (2)

U709Q2 claims 1. A process for the production and tread renewal of tires, the carcass and tread of which consists of different types of rubber, characterized in that, that a layer of saturated ethylene-α-olefin copolymer or from a weakly unsaturated one Ethylene, propylene and a non-conjugated diene consisting of terpolymers that are an organic peroxide of sulfur contained as a vulcanizing agent, directly on a layer of a natural rubber or a synthetic diene rubber, which is a white mineral filler and vulcanizing agent based on Contains sulfur and accelerators, applies and vulcanized the two layers. 2. The method according to claim 1, characterized in that one uses a copolymer or a terpolymer having a Mooney Viskositfit ML (1 + 4) of 60 or more at 100 ⁰ C. J. The method according to claim 1 or 2, characterized in that a copolymer or terpolymer is used whose Mooney viscosity is reduced to a value ML (1 + 4; at 100 ⁰ C of at least 25 by adding a paraffin oil. 4, method according to claim 1 to 3 »characterized in that that the mixed vulcanization is carried out at temperatures between 140 and 180 ° C. 009808/1557 BATH ORIGINAL