DE1247623B - Process for vulcanizing rubber - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. GL:

C08d

German class: 39b-7

Number: 1247 623

File number: M 54088IV d / 39 b

Filing date: August 30, 1962

Opened on: August 17, 1967

Butadiene-styrene rubber as well as oil-extended butadiene-styrene rubber are becoming in large measure Treads used for vehicle tires. These rubbers as well as all other synthetic ones Compared to natural rubber, rubbers have certain disadvantages, only the minor one here Resistance to tear propagation should be mentioned. Using cis-1,4-polybutadiene could this deficiency can be partially remedied as there is better resistance to education and Has crack growth. On the other hand, butadiene-styrene-rubber is much cheaper than cis-1,4-polybutadiene. The cut resistance of vulcanized rubber is also already known to improve the use of certain white fillers and carbon blacks.

Vulcanizates have also been made from oil-extended butadiene-styrene rubber, which in addition to less contain cyclohexyl-2-benzthiazylsulfenamide and diphenylguanidine as 2% elemental sulfur. It is also known to have oil-extended butadiene-styrene rubber with less than 2% elemental sulfur Vulcanize dibenzothiazyl disulfide alone and / or tetramethylthiuram disulfide. One already has oil-extended butadiene-styrene rubber with diphenylguanidine, dibenzothiazyl disulfide and less than 2% elemental sulfur vulcanized.

In addition to elemental sulfur, dibenzothiazyl disulfide has also been used for such rubber mixtures and dithiodimorpholine used for vulcanization.

However, vulcanizates made from these mixtures show severe aging when exposed to heat, d. that is, they show a substantial drop in physical values.

It has also already been proposed that one of dibenzot mazyl disulfide, mercaptobenzothiazole, tetramethylthiuram disulfide, p, p '- dibenzoylquinone dioxime or parachinone dioxime and 4,4-dithiodimorpholine and / or small amounts of elemental sulfur to use existing mixture for vulcanizing natural rubber. Vulcanizates from such Mixtures have excellent aging resistance when exposed to heat.

It has now been found that the use of the abovementioned vulcanizing agent mixture in oil-extended Butadiene-styrene rubber also into vulcanizates with excellent aging properties leads when these are subjected to the effects of heat.

The invention relates to a method for vulcanizing rubber with the addition of

Process for vulcanizing rubber

Applicant:

Metzeler Aktiengesellschaft,
Munich 12, Westendstr. 131-133

Named as inventor:

Hrishikesh Chandra Roy, Planegg near Munich

Amine-based anti-aging agents, dibenzothiazyl disulfide, mercaptobenzothiazole, tetramethylthiuram disulfide and ρ, ρ'-Dibenzoylctiinondioxime or Parachinondioxime, also plasticizers, zinc oxide, Stearic acid, adhesive resins, degrading agents, carbon black and wax and 4,4'-dithiodimorpholine and / or at most 1 part by weight of sulfur per 100 parts by weight of rubber, which is characterized in that as Rubber "oil-extended butadiene-styrene rubber is used.

The following test examples explain the invention.

Comparative Example A.

A tread compound was produced with the following composition:

Mixture parts by weight of oil-extended butadiene-styrene

Rubber 130

Coumarone resin, liquid 2.8

Zinc oxide. 3

Stearic acid 2

N-phenyl-N'-isopropyl-p-phenylene-

diamine 2

Phenyl-ß-naphthylamine 1

Phenyl-a-naphthylanün 1

Wax 3

Dismantling agents. 0.2

Furnace soot 70

Mixture of sulfur and
oil-extended butadiene-styrene

Rubber (1: 1) 3.86

4.58 parts of butadiene-styrene rubber + 1.56 parts of N-cyclohexyl-2-benzothiazylsulfenamide with oil (5: 1) + 0.1 part stearic acid ... 6.24 0.31 parts butadiene-styrene rubber + 0.22 parts of diphenylguanidine with oil (10: l) 0.53

709 637/725

Test results Test results

Module at 300% (kg / cm ² ) module at 500% (kg / cm ² ) tensile strength (kg / cm ² ), ...

Elongation at break (%)

Shore hardness ⁰ A

Elasticity (%)

Cut resistance (kg / cm) .. Notch toughness (kg / cm) ... Mooney t ₅ (minutes)

Heating at 143 ⁰ C

(Minutes) 5 45 60 63 62 144 144 190 192 10 605 615 55 56 30th 30th 9.4 9.1 13th 13th 15th 20th

Aging 3 days at IOO ⁰ C

Module at 300% (kg / cm ² ) Module at 500% (kg / cm ² ) Tensile strength (kg / cm ² )

Elongation at break (%)

Shore hardness ⁰ A .... ·

Elasticity (%)

Cut resistance (kg / cm) .. Notch toughness (kg / cm) ....

Heating at 143 ° C (Minutes) 45 60 138 148 160 166 340 345 69 66 23 22nd 8.2 6.6 9 9

35

Comparative example B

A tread mixture similar to that in Example A was made:

Mixture parts by weight

Oil-extended butadiene-styrene rubber

Plasticizer 9.8

Coumarone resin, liquid ■ 2.8

Zinc oxide stearic acid

N-phenyl-N'-isopropyl-p-phenylene-

diamine ....

Phenyl-jS-naphthylamine Phenyl - «- naphthylamine wax

Dismantling agent 0.2

Furnace black 82.5

Mixture of sulfur and oil-extended butadiene-styrene

Rubber (Irl) 4.4

4.58 parts of butadiene-styrene rubber + 1.56 parts of N-cyclohexyl-2-benzothiazylsulfenamide with

Oil (5: 1) + 0.1 part stearic acid ... 6.24 0.31 parts butadiene-styrene rubber + 0.22 parts diphenyl

guanidine with oil (10: 1) 0.53

Module at 300% (kg / cm ² ) module at 500% (kg / cm ² )

Tensile strength (kg / cm ² )

Elongation at break (%)

Shore hardness ° A

Elasticity (%)

Cut resistance (kg / cm) .. Mooney t _s (minutes) ....

Heating at 143 ° C (minutes) 45

71 144 170 585

56

26 9.8

24

75 148 166 555

56

23 9.8

Aging 3 days at IOO ⁰ C

Module at 300% (kg / cm ² ) module at 500% (kg / cm ² )

Tensile strength (kg / cm ² )

Elongation at break (%)

Shore hardness ⁰ A

Elasticity (%)

Cut resistance (kg / cm) ..

Heating at 143 ⁰ C (minutes) 45

140

152 330

74

23 9, p

134

146 325

71

23 9.2

The above results of Comparative Examples A and B are produced with known mixture formulations which are intended to be used for comparison with vulcanizates made by the claimed process were manufactured.

Example!

The following tread mixtures with the vulcanizing agents to be used according to the invention were manufactured:

Oil-extended butadiene-styrene

rubber

Coumarone resin, liquid

Zinc oxide

wax

Stearic acid

N-phenyl-N'-isopropyl-p-phenylene-

diamine

Phenyl- / S-naphthylamine

Phenyl-a-naphthylamine

Dismantling agents (Renazit IV) ...

Soot (Corax 6)

Oil sulfur, 0.2 (10% oil)

4,4'-dithiodromorpholine

Dibenzothiazyl disulfide

Mercaptobenzothiazole

Tetramethylthiuram disulfide

ρ, ρ'-dibenzoylquinone dioxime

a I b parts by weight

137.5 137.5 2.8 2.8 3 3 3 3 2 2 2 2 1 1 1 1 0.2 0.2 70 70 0.55 0 0 0.6 2 2 0.5 0.5 0.1 0.1 1.5 1.5

ί 247 623

Test results Test results

Heating at 143 ⁰ C Heating at 143 ° C (Minutes) 5 (Minutes) a C. d 45 60 45 60 45 60 45 60 Module at 300% (kg / cm ² ) 49 49 29 28 Module at 300% (kg / cm ^a ) 59 63 • 87 73 Module at 500% (kg / cm ² ) 97 98 61 60 ¹⁰ modules at 500% (kg / cm ² ) 114 120 Tensile strength (kg / cm ³ ) .. 147 142 110 106 Tensile strength (kg / cm ² ) ... 144 140 126 124 Elongation at break (%) 720 690 875 865 635 580 405 470 Shore hardness ⁰ A 55 55 53 52 Shore hardness ⁰ A 57 57 62 60 Elasticity (%) 23 22nd 21 22nd Elasticity (%) 25th 24 25th 24 Notch toughness (kg / cm) .. 25th 24 32 29 ¹ S notch toughness (kg / cm) .. 21 18th 14th 15th Pull-out strength (kg / cm) 74 70 59 56 Pull-out strength (kg / cm) 57 60 59 60 Mooney (minutes) over 30 29 Mooney t _s (minutes) ... 26Va over 30

Aging 3 days at IOO ⁰ C

Aging for 3 days at 100 ° C

Heating at 143 ° C (Minutes) a b 45 60 45 60 Module at 300% (kg / cm ² ) ... 76 73 50 45 Module at 500% (kg / cm ² ) ... 128 124 92 83 Tensile strength (kg / cm ² ) 138 132 112 102 Elongation at break (%) 550 525 645 665 Shore hardness ⁰ A 60 60 56 57 Elasticity (%) 22nd 22nd 21 20th Notchiness (kg / cm) 20th 20th 27 27 Pull-out strength (kg / cm) ... 59 68 63 56

Modulus at 300% (kg / cm ² ).

Modulus at 500% (kg / cm ² ).
Tensile strength (kg / cm ² )

Elongation at break (%)

Shore hardness ° A

Elasticity (%) ...

Notch toughness (kg / cm)

Pull-out strength (kg / cm).

Heating at 143 ° C

(Minutes) C. i 45 60 45 60 110 93 66 154 130 118 104 435 435 235 265 65 62 68 63 27 27 26th 27 13th 15th 7th 13th 48 55 48 51

The test results for example show that the modulus and notch toughness compared to the vulcanizates of Comparative Examples A and B are improved.

The test results show the improvement in notch toughness compared to the comparison tests.

Example 3 Example 2

The following mixtures were produced:

C. d Parts by weight Oil-extended butadiene-styrene rubber 137.5 137.5 Coumarone resin, liquid 2.8 2.8 Zinc oxide 3 3 wax 3 3 Stearic acid 2 2 N-phenyl-N'-isopropyl-p- 2 2 Phenyl / 5-naphthylamine 1 1 Phenyl-a-napmhylamine 1 1 Dismantling agents 0.2 0.2 12th 12th Oil sulfur, 0.2 0.77 0.99 soot 82.5 82.5 Mercaptobenzothiazole 0.5 0.5 Tetramethylthiuram disulfide 0.1 0.1 2 2 ρ, ρ'-dibenzoylquinone dioxime 1.5 1.5

A rubber mixture was prepared containing both sulfur and dithiodimorpholine.

Parts by weight

Oil-extended butadiene-styrene

Rubber 137.5

Coumarone resin, liquid - 2.8

Zinc oxide 3

Wax 3

Stearic acid 2

N-phenyl-N'-isopropyl-p-phenylene-

diamine 2.

Phenyl- / 3-naphthylamine · 1

Phenyl-a-naphthylamine 1

Dismantling agent 0.2

Soot 70

4,4'-dithiodimorpholine 0.4

Oil sulfur, 0.2 0.55

Dibenzothiazyl disulfide 2

Mercaptobenzothiazole 0.5

Tetramethylthiuram disulfide 0.1

ρ, ρ'-dibenzoylquinone dioxime 1.5

Claims (1)

Test results Heating at 143 ° C (Minutes) 45 60 Module at 300% (kg / cm ² ) 66 66 Modulus at 500% (kg / cm ^ j 124 126 Tensile strength (kg / cm ³ ) 164 170 635 645 Shore hardness ⁰ A 59 58 Elasticity (%) 30th 30th 19th 19th 65 66 Mooney i ₅ (minutes) over 30 Aging 3 days at IOO ⁰ C Module at 300% (kg / cm ² ) module at 500% (kg / cm ² ) Tensile strength (kg / cm ² ) Elongation at break (%) Shore hardness ⁰ A Elasticity (%) Notch toughness (kg / cm) ... Pull-out strength (kg / cm) .. Heating at 143 ° (minutes) 45 60 102 104 150 150 455 455 64 61 30th 30th 15th 16 63 56 10 With the vulcanization system used according to the invention, an approximation of the quality of Tread of a tire made of oil-extended butadiene-styrene rubber on a tire made of butyl rubber possible. Vulcanizates ₅ made with 4,4'-dithiodimorpholine show better results than those made with elemental sulfur alone. Claim: A process for vulcanizing rubber with the addition of antioxidants, amine-based, dibenzothiazyl _j mercaptobenzothiazole, TetramethylthiuramdisuIfid and p, p'-dibenzoylquinonedioxime or paraquinonedioxime, further plasticizers, zinc oxide, stearic acid, tackifier resins, disintegrants, carbon black and wax, as well as 4,4'-dithiodimorpholine and / or at most 1 part by weight of sulfur per 100 parts by weight of rubber, characterized in that oil-extended butadiene-styrene rubber is used as the rubber. Considered publications:
Canadian Patent No. 344,065;
U.S. Patent No. 1,893,846;
Chemisches Zentralblatt, 1961, p. 16 303;
Rubber and Asbestos, 1954, pp. 112 to 118.