DE1180123B - Rubber compounds with improved vulcanization properties - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN WjSw PATENT OFFICE

EDITORIAL

Boarding school Cl .: -COSc;

C08d
German KL: 39 b-4/01

Number: 1180123

File number: F 26566IV d / 39 b

Filing date: September 6, 1958

Opening day: October 22, 1964

The invention relates to rubber compounds with improved vulcanization properties.

Mixtures of chlorinated butyl rubber and natural or synthetic rubber are known Manufacture rubber that has good mechanical properties.

It is also known that both synthetic butadiene-styrene rubber and butyl rubber can be vulcanized with 2,6-dimethylol-4-alkylphenols.

Although the vulcanization of butyl rubber, as well as the vulcanization of butadiene-styrene rubber With sulfur, alone leads to usable VuI-kanisaten, difficulties arise when one Mixtures of butyl rubber and butadiene-styrene rubber vulcanized. Such mixtures result Vulcanizates with a very low modulus of elasticity and low tensile strength because they are strong Unsaturated butadiene-styrene rubber consumes all of the sulfur during vulcanization before the very little unsaturated butyl rubber adopts sulfur. Because of this difference in recording speed for sulfur, the two mixture components are at different rates vulcanized.

The invention relates to rubber mixtures with improved vulcanization properties, the (1) from a rubber-like copolymer of 70 to 99.5% of an isoolefinic hydrocarbon having 4 to 7 carbon atoms and 0.5 to 30% of a conjugated diolefinic hydrocarbon with 4 to 7 carbon atoms, (2) a rubber-like copolymer of a diolefinic hydrocarbon having 4 to 7 carbon atoms with a vinyl monomer, (3) a halogenated rubber compound with improved vulcanization properties

Applicant:

The Firestone Tire & Rubber Company, Akron, Ohio (V. St. A.)

Representative:

Dipl.-Ing. K. Lengner, patent attorney, Hamburg 26, Jordanstr. 7th

Claimed priority:

V. St. v. America dated May 13, 1958 (735 005)

rubber-like copolymer made from an isoolefinic hydrocarbon with 4 to 7 carbon atoms and a conjugated diolefinic hydrocarbon having 4 to 7 carbon atoms and less There are proportions of a 2,6-dimethylolphenol substituted in the 4-position by an alkyl radical.

The mixtures according to the invention are suitable for many vulcanized objects, for example for tires, especially tire treads, useful.

When using chlorinated butyl rubber, the chlorine content of the polymer should be 0.8 to 1.5 percent by weight, however, it is preferably 1 percent by weight.

When using brominated butyl rubber, the bromine content should be at least 0.5% bromine, based on on the weight of the polymer, but less than the amount of bromine that the polymer completely would satiate. Butadiene-styrene copolymers are particularly suitable for the mixtures according to the invention.

example 1 The following mixtures were produced:

Butyl rubber

Butadiene styrene rubber (70:30)

Chlorinated butyl rubber

2,2-dimethylol-4-octylphenol

soot

Stearic acid

Zinc oxide

oil

accelerator

sulfur

100

40
1
5

1.50
2.20

50 50

40.00
1
5
8th

1.89
2.13

30 50 20 10

45 1 7 4

10

50

40

10

45

409 708/435

The mixtures were produced on a two-roll mill, with the rubber-like constituents first mixed and then carbon black, pigments, accelerators and oils were added.

The samples were kept at 163 ° C in the following Table indicated time vulcanized and on a Scott tester in a known manner with the checked the following results:

1 2 3 4th 5 6th 163 213 60 77 86 118 123 188 70 112 105 118 100 169 63 120 109 118 26th 141 56 77 112 44 163 - 105 -. - 58.0 - - - - - 795 385 135 420 355 320 635 325 110 335 290 250 435 285 110 295 245 245

Tensile strength (kg / cm ² )

Vulcanized for 15 minutes

Vulcanized for 30 minutes

Vulcanized for 45 minutes

300% module (kg / cm ² )

Vulcanized for 15 minutes

Vulcanized for 30 minutes

Vulcanized for 45 minutes

Elongation at break (%)

Vulcanized for 15 minutes

Vulcanized for 30 minutes

Vulcanized for 45 minutes

From the results it can be seen that mixtures of chlorinated butyl rubber with not halogenated butyl rubber and with butadiene-styrene copolymers, those with 2,6-dimethylol-4-octylphenol have been vulcanized to provide vulcanizates with good mechanical properties.

The results of batch 3 show that a VuI-kanisat from a mixture of 50 parts of non-halogenated butyl rubber and 50 parts of butadiene-styrene rubber has very low tensile strength and very low elongation and at Stretch breaks before it has reached 300% of its original size. But this sample has poorer properties than samples 1 and 2, which are made from pure butyl rubber or pure butadiene-styrene rubber exist. However, useful vulcanizates with a mixture according to approaches 4 to get 6.

Example 2

The improved effect when using different percentages of chlorinated butyl rubber in relation to the total in the butyl rubber-butadiene-styrene-rubber mixture Any butyl rubber present can be seen from the following examples. The approaches were in the previously described manner mixed in a two-roll mill and at 163 ° C for the specified time vulcanized.

Butadiene styrene rubber ..

Butyl rubber

Chlorinated butyl rubber.

soot

Zinc oxide

oil

2,6-dimethylol-4-octylphenol

82

7th
11
40

0.38
12th

69
19th
12th
41

0.96
12th

47 38 15 42

1.93 12

10

72

18th

45

12th

1 2 3 4th 5 Tensile strength (kg / cm ² )
Vulcanized for 15 minutes 197 211 179 134 120 Vulcanized for 30 minutes 232 214 185 149 135 Vulcanized for 45 minutes 218
83 207
84 165
90 155
90 139
58 300% module (kg / cm ² )
Vulcanized for 15 minutes 135 116 135 128 90 Vulcanized for 30 minutes 156
530 146
560 146
495 142
440 105
550 Vulcanized for 45 minutes 420 410 370 335 430 Strain (%)
Vulcanized for 15 minutes 380 370 330 320 395 Vulcanized for 30 minutes Vulcanized for 45 minutes

Example 3

Studies have been carried out to determine the useful concentration range of p-substituted To determine dimethylolphenol in the mixture of butadiene-styrene and butyl rubber. The following samples were made:

Butadiene-styrene rubber

Butyl rubber

Chlorinated butyl rubber

soot

Zinc oxide

Plasticizers

2,6-dimethylol-4-octylphenol

1 2 3 60.00 60.00 60.00 30.00 30.00 30.00 10.00 10.00 10.00 45.00 45.00 45.00 7.00 7.00 7.00 4.00 4.00 4.00 3.00 10.00 20.00

60.00

30.00

10.00

45.00

7.00

4.00

30.00 The required amount of brominated butyl rubber is the same as that of chlorinated Butyl rubber.

The samples were prepared in the manner described above and when tested gave the following results physical properties:

The samples were prepared in the manner previously described and had the following physical Features on:

1 2 3 4th Tensile strength (kg / cm ² ) Vulcanized for 15 minutes 26.4 84.4 118 128 Vulcanized for 30 minutes 42.2 132 139 144 Vulcanized for 45 minutes 49.2 146 146 144 300% module (kg / cm ² ) Vulcanized for 15 minutes 17.6 59.8 77.3 82.6 Vulcanized for 30 minutes 35.0 114 141 - Vulcanized for 45 minutes 40.4 134 - - Strain (%) Vulcanized for 15 minutes 615 415 430 430 Vulcanized for 30 minutes 420 335 295 280 Vulcanized for 45 minutes 415 325 250 240

1 2 3 Tensile strength (kg / cm ² ) Vulcanized for 15 minutes 88 144 148 Vulcanized for 30 minutes 120 156 153 Vulcanized for 45 minutes 128 158 151 300% module (kg / cm ² ) Vulcanized for 15 minutes 63 97 112 Vulcanized for 30 minutes 105 120 130 Vulcanized for 45 minutes 120 128 137 Strain (%) Vulcanized for 15 minutes 425 425 385 Vulcanized for 30 minutes. 345 385 345 Vulcanized for 45 minutes 325 360 330

The results show that up to 30 parts of 2,6-dimethylol-4-octylphenol can be used, with 10-25 parts being preferred.

Example 4

To the usefulness of brominated butyl compounds To show, the following blends were made:

Butadine-styrene rubber

Butyl rubber

Brominated butyl rubber

soot

Zinc oxide

Plasticizers

2,6-dimethylol-4-octylphenol ..

1 2 50 50 45 30th 5 20th 45 45 7th 7th 4th 4th 10 10

50

10

40

45

10

Claims (1)

Claim: A rubber composition having improved cure properties, comprising (1) a rubbery copolymer of 70 to 99.5% of a isoolefinischen hydrocarbon having 4 to 7 carbon atoms and 0.5 to 30% egg ^nes conjugated diolefinic hydrocarbon having 4 to 7 carbon atoms, (2) a rubbery Copolymer of a diolefinic hydrocarbon with 4 to 7 carbon atoms and a vinyl monomer, (3) a halogenated rubber-like copolymer of an isoolefinic hydrocarbon with 4 to 7 carbon atoms and a conjugated diolefinic hydrocarbon with 4 to 7 carbon atoms and (4) small proportions of a 4- Position substituted by an alkyl radical 2,6-dimethylolphenol. Considered publications:
U.S. Patents Nos. 2,649,431, 2,701,895,
2 732 354, 2 804 448. 409 708/435 10.64 ® Bundesdruckerei Berlin