DE2328527A1 - NON-FLOATING ACCELERATORS - Google Patents

Description

The present invention "relates to compounds which are effective Represent accelerators for the vulcanization of elastomers. In particular, the invention relates to zinc oxazolidine carbodithioates and zinc thiazolidine carbodithioates and their pyridine adducts, which Compounds are particularly suitable for the inhibition of blooming phenomena on the surface of vulcanized elastomers, especially of elastomeric terpolymers made from ethylene, propylene and a diene monomer (EPDM elastomers).

Elastomer vulcanization, in which an accelerator is used together with sulfur or another vulcanizing agent, requires a non-efflorescent accelerator ("non-efflorescent accelerator") with sufficient effectiveness. The thiurams, such as tetramethylthiuram disulfide and tetraethylthiuram disulfide, are highly effective accelerators, but cause undesirable surface efflorescence on the elastomer vulcanizates. Surface efflorescence is an adverse phenomenon caused by the appearance of a pesticide or oil coating

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is characterized on the vulcanizate surface. The coating formation is due to the fact that at least one component of the vulcanized elastomer migrates to the surface or diffused. Diffusion can occur rapidly, for example within a few days or a week. The efflorescence is special then detrimental when the elastomer is used for electrical insulation purposes. The efflorescence also helps EPDM elastomers pose a particular problem. EPDM elastomers are terpolymers of ethylene, propylene and a diene monomer, like 11-ethyl-ί, 11-tridecadiene, 1,5-cyclooctadiene, 1,5-hexadiene, 5-ethylidene-2-norbornene, 5-methylene-2-norbomene, dicyclopentadiene and 2,5-norbornadiene. When curing EPDM elastomers is also used because of the low level of unsaturation in the polymer a highly effective accelerator is needed.

US Pat. No. 3,674,701 describes a non-blooming accelerator composition which is a mixture of a certain thiourea compound with the zinc salt of the reaction product of essentially equimolar amounts of ethanolamine, formaldehyde and carbon disulfide. It was now possible, by solvent extraction and crystallization methods, to isolate a special new compound from the aforementioned, complex reaction product mixture, which as such is a non-blooming accelerator. This means that in order to achieve good results in the vulcanization of EPDM elastomers, it is not necessary to use thiourea or other additives together with this compound. A more convenient method for preparing this new compound, as well as similar compounds having the same utility and unexpected advantages, has also been devised.

The compounds of the present invention have the general formula

R "1

il

-s

2 -

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in which X is a sulfur or oxygen atom, R, R ¹ , R ² and R ^ independently in each case a hydrogen atom, a lower alkyl radical (for example with 1 to 8 carbon atoms, preferably a methyl group), a trichloromethyl group, a phenyl group or a substituted phenyl group (where one or

1 1

several substituents from the G group NRR, OH, OR and Cl is or are present) mean, Ci = HgN represents ^a pyridine molecule and η is an integer from 0 to 5 (generally up to 3), the higher values for η are due to the acidic nature of the substituents R to R ^.

A convenient method for the preparation of the compounds of the invention is that you first an oxazolidine or Thiazolidine (or a substituted derivative of these compounds) of the general formula

(in which X is an oxygen or sulfur atom) by reacting an amino alcohol or amino mers apt ans with formaldehyde and ^{subjecting the triazine obtained to pyrolysis at about 100 to 200 °} C. * The method of A. Paquin, Ber . 82 (1949), p. 316. A typical process for the preparation of such an oxazolidine will now be described; the reaction scheme below illustrates this method.

example 1

Manufacture; an oxazolidine of 1 _t 3T5-tris (2-hydroxyethyl) - hexahydro-1,3, 5-triazine *

3 NH ₂ CH ₂ CH ₂ OH + 3 HCHO

H ₂ CH ₂ OH

3 0 9 8 8 1/12 0 2

Is added 366 g (6 mol) of ethanolamine at 40 to 45 ⁰ C dropwise, under stirring with 486 g (6 moles) 37prozenti * eng formaldehyde solution. After a further hour at 40 to 45 ⁰ C, evaporate the water in a rotary vacuum evaporator at 50 to 55 ⁰ C from. 447 g of an amber-colored oil remain as residue; this is 1,3,5-tris (2-hydroxyethyl) hexahydro-1,3,5-triazine, containing 18.98 i 'N (ber.i 19.17 $ N).

Distilling a portion of 24.1 g of the aforesaid triazine in a distilling apparatus of Pyrex glass, which has an acetone bath with the aid of a dried egg s / (-75 ⁰ C) cooled distillate receiver. The steam temperature is 52 to 69 ° C at 1.2 mm pressure. The temperature of the bladder is 118 to 139 ° C. The oil bath in which the bubble is immersed has a temperature of 153 to 172 ^° C. As distillate are obtained 22.2 g of colorless oxazolidine (very viscous at -75 ⁰ C).

Obtained zinc oxazolidincarbodithioat the invention or zinc thiazolidincarbodithioat by reacting the oxazolidine described above (or the corresponding thiazolidine) at about 0 to 75 ⁰ C with carbon disulfide and Zinkäcetat in a suitable solvent. Examples of useful solvents are pyridine, triethylamine and tributylamine or methanol, isopropanol, ethanol and butanol, which advantageously contain a small amount of a basic amine such as triethylamine, tributylamine, pyridine, dimethylaniline and diethylaniline. The preferred solvent system, however, is pyridine, which not only functions as a reaction medium, but also provides the desired basicity. The reaction products are generally obtained in the form of their pyridine adduct, which contains up to 5 molecules of pyridine. The pyridine can generally be split off from the zinc salt by heating the adduct to about 50 to 150 ^° C. under reduced pressure. However, this is not necessary since the presence of the pyridine in the salt does not in any way impair the suitability of the compounds as non-blooming vulcanization ^{accelerators 1} .

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The following examples explain the preparation of special compounds according to the invention (“Ac” means the group ΟΗ, ΟΟ).

Example 2 Production of zinc bis (3-oxazolidine carbodithioate)

+ 2 CS,

Zn (OAc),

Pyridine

C (S) S

A mixture of 600 g of pyridine, 116 g (1.52 mol) of carbon disulfide and 139.5 g (0.76 mol) of anhydrous zinc acetate is added with stirring and cooling (to maintain a temperature of 15 to 25 ^° C.) with 111, 1 g (1.52 mol) of freshly distilled cold oxazolidine, which according to A. Paquin, Chem. Ber. 82 (1949), page 316 from 1,3,5-Tras- (2-hydroxyethyl) -hexahydro-1,3,5- -triazine. The batch is left to stand at room temperature overnight. The precipitated product is then filtered off, washed with water and air-dried. This gives 193.5 g of a Monopyridinaddukts of mp. 195-200 ⁰ C (decomposition). By diluting the filtrate with water, a further 34.4 g are obtained (total conversion 68.3 liters ) .

The pyridine adduct is freed from pyridine by vacuum drying at 80 to 85 ^{° C.} The weight loss shows that the pyridine / zinc salt molar ratio was 1: 1. Drying gives the desired zinc bis (3-oxazolidine carbodithioate) in the form of a white, crystalline product with a melting point of 223 to 225 ^° C. (decomposition).

C H N Zn

C ₈ H ₁₂ N ₂ O ₂ S ₄ Zn; calc .: 26.56 3.32 7.75 18.10

Found: 26.75 3.46 7.63 17.9

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Production of zinc-M s --- (S-tri dithioate)

, + 2CS ₉ + Zn (OAc) ₉ ^ »

3 c. "i. Isopropanol

Triethylamine

Zn

95.2 g of 2-trichloromethyloxazolidine (prepared according to W. Ruske and I «Hartmann, J« Prakt. Chem. 18 (1962), page 146) are dissolved in a mixture of 300 ml of isopropanol and the solution is treated dropwise with 50, 5 g (O ₁₁ 5 mol) of carbon disulfide "is subsequently reacted 43.9 g (0.25 mol) of anhydrous zinc acetate added. The reaction mixture is ^{heated to 45 to 50 °} C. for 2 hours, cooled to room temperature and diluted with 1 liter of water. The precipitate formed is filtered off, washed thoroughly with water and dried in vacuo. This gives 86.3 g of crude product, mp. 193 kis 195 ⁰ C (decomposition) ,, by extraction of the crude product with hot benzene to obtain 38 g of the desired CarbodithioatSg welshes at 208 G ⁰ sinters and bsi 213 to 216 ° C (decomposition) melts »

- CHN S

DgS ₄ Zm ber.s 20.12 '1.68 4.69 21.46 found: 20.19 2.08 4.67 20.96

Example 4

Production of the pyridine adduct of zinc bis (2-t richl ormethyl-3-oxazolidine carbodithioate)

+ 2

+ Zn (OAc) ₂

Pyridine

CCl

30.4 g (0 ^ 16 mol) of 2-trichloromethyloxazolidine are dissolved (manufacture according to W. Ruske and I. Hartmann, J. Prakt * Chem. 18 (1962),

Page 146) in 480 g of pyridine and added to the solution with rapid "in Bäumtemperatu? Dropwise with 14» 4 g (0.184 mol) of

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Carbon disulfide. 15.2 g (θ, 083 mol) of anhydrous zinc acetate are then added. The reaction mixture is heated to 45 "to 50 ^° C. for 3 hours, cooled to room temperature and then diluted with 1 liter of water. The precipitated product is filtered off and dried in vacuo at room temperature. 33.4 g of the desired pyrid inaducts of Pp ., 205-207 ⁰ C (decomposition) A small, recrystallized from methanol analytical sample sintered at 209 ° C and melts with decomposition at 212-214 ⁰ C.

C H NS Cl Zn

C ₁₀ H ₁₀ Cl ₆ N ₂ O ₂ S ₄ Zn ^ ₅ H ₅ N; calc .: 26 _s 65 2.22 6.23 18.95 31.54 9.68

found: 26.70 2.74 6.30 19.60 31.37 9.55

Example 5 Preparation of zinc bis (2,2-dimethyloxazolidine-3-carbodithioate )

2 CS ₂ + Zn (OAc) ₂

Pyridine

A solution of 15.2 g (0.2 mol) of carbon disulfide in 150 g of pyridine is added while stirring and cooling with 20 g (0.2 mol) of 2,2-dimethyloxazolidine (preparation according to E. Bergmann et.al., J. Am. Chem. Soc. 75 (1953), page 358). In the solution 18.3 g (0.1 mol) of anhydrous zinc acetate was added at 25 to 3O ⁰ C with stirring. The solution is left to stand overnight at room temperature and then filtered. This gives 15.2 g of crude product. A further 10.4 g are obtained by vacuum evaporation of the filtrate and dilution of the residue with ethanol. After combining and vacuum drying of the crude product at 100 ⁰ C to obtain 17.8 g of the desired Carbodithioats from Pp, 188-190 ⁰ C (decomposition). A small sample that is dissolved in hot chloroform and then precipitated using hexane (pp. 192 to 193 ^° C. with decomposition) "has the following analytical values ^:!

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C ₁₂ H ₂₀ N ₂ O ₂ S ₄ Zn; ber.

found

C H N Zn 34.50 4.79 6,, 71 15.67 34.22 4.47 6.84 15.20

Example 6

Preparation of the tripyridine adduct of zinc-bis - / ^ - (3-ethoxy-4- -hydro3cyphenyl) -oxazolidine-3-carbodithioate /

\ VCHO + H ₂ NCH ₂ CH ₂ OH

C ₂ H ₅ O

I = NCH ₂ CH ₂ OH ^ HO- / 'V

Zn (OAc) ₂ in pyridine

Zn.3 C ₅ H ₅ N

A mixture of 80 ml of isopropanol, 15.7 g (0.094 mol) of 3-ethoxy-4-hydroxybenzaldehyde and 6 g (0.098 mol) of ethanolamine is heated in a steam bath for 1 hour. It is then filtered at room temperature. In this case, one obtains 157 Soc 19.3 g of a crystalline product, mp. 160 ⁰ C. Because of its IR spectrum (1650 cm "C = N, LW Daasch, JA Am. Chem.. 73 (1951), page 4523 ) the product apparently consists mainly of the Schiff's base ß- (3-ethoxy-4-hydroxybenzylideneamino) -ethanol, which can be in tautomeric equilibrium with the cyclic 2- (3-ethoxy-4-hydroxyphenyl) oxazolidine.

A mixture of the aforementioned crystalline product with 40 g of pyridine, 7.6 g (0.1 mol) of carbon disulfide and 9.2 g (0.05 mol) of anhydrous zinc acetate is heated to 50 to 55 ° C. for 90 minutes and then at room temperature overnight ditched. After filtering and washing the precipitate with hexane, 38.1 g of the pyridine adduct of melting point 106 to 112 ^° C. are obtained.

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53 3 σ H 94 8th N Zn 2 3 2 8th 527 53 , 77 4, 95 7th , 04 7.51 about _e : , 25 4, , 74 7.46 found:

The IR spectrum of this product shows no absorption at 1650 cm "", which is characteristic of the aforementioned Schiff base. This proves that the Schiff base has passed into the corresponding tautomera oxazolidine, which in turn reacted _{with CS 2} and Zn (OAc) _{2 »}

Example 7

Production of the pyride adduct of zinc bis - /]? - (j -dimethylaminophenyl) -oxazolidine-3-carbodi thioate7

This adduct is prepared as in Example 6, but using p-dimethylaminobenzaldehyde instead of 3-ethoxy-4-hydroxybenzaldehyde. The residue obtained after evaporation is washed with water and the remaining solid substance is dissolved in dimethylformamide at room temperature. The filtered solution is diluted with water. The desired adduct is obtained with a melting point of 91 to 93 ^° C. (decomposition). It has the formula

C (S) S Zn »CcHcN, in which R is a group of the formula

means. This structure is based on the IR spectrum and through Elemental analysis determines:

C H Zn

C ₂₄ H ₃₀ N ₄ O ₂ S ₄ Zn ^ ₅ H ₅ N; calc .: 51.30 5.16 9.64

found:. 51.72 5.82 9.13

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Example 8 Preparation of zinc Ms- (thiazolidine-3-carbodithioate)

+ 2 CS ₉ + Zn (OAc) ₉ "

Pyridine

H ₂

+ 01 "

C (S) S

Zn

175 g (1.4 mol) of thiazolidine hydrochloride (prepared according to S. Ratner and H. Clarke, J. Am. Chem. Soc. 59 (1937), page 200) are introduced into 250 g of pyridine with stirring and cooling . When the solution is complete, 106.4 g (1.4 mol) of carbon disulfide are added dropwise. 128.5 g (0.7 mol) of anhydrous zinc acetate are then added. The resulting reaction mixture is stirred for 2 hours at 40 to 50 ⁰ C and the precipitate formed is filtered off at 5 to 10 ⁰ G. The crude solid product is washed with water and freed finally by vacuum drying at 120 ⁰ C of pyridine. This gives 147.8 g of the desired product »This decomposes gradually with the beginning at 200 ⁰ C and without a defined end point of decomposition," A small sample _s which is washed with hot benzene, seigt the following analysis:

C H N 'Zn calc .: 24.40 3.05 7.12' 16.62 found s 24.46 2.95 - 7.31 16.58

Example 9

Production of the dipyridine adduct of zinc-bis-Zl2-trichloromethyl) - -thiazolidine-3-carbon dithio at7

f - \ pyridine 2 S _n ^ NH + 2CS ₂ + Zn (OAc) ₂ - f

CCl-

Zn. 2 C ₅ H ₅ N

158.2 g (2 mol) of pyridine are mixed with 66 g (0.32 mol) of 2-trichloromethylthiazolidine (preparation according to B. Sweetraan et al., J. led. Ghem. 12 (1969), page 888) and carry in the resulting solution inaerfealb of 10 minutes with stirring at 2O ⁰ C 24.4 g

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(0.32 mole) carbon disulfide. The solution is then ^{heated to 25 °} C., at which temperature 29.4 g (0.16 mol) of zinc acetate are added in the form of partial amounts over the course of 30 minutes. The temperature is kept at 25 ° C. during the addition with the aid of an ice bath. The clear, amber-colored solution obtained is stirred for a further 17 hours at room temperature. The precipitate formed during this continued stirring is filtered off and washed four times with 500 ml of water each time. After air drying, 100 g (79 ° conversion) of an off-white product with a pp. 181 to 183 ° C. (some gas evolution) are obtained.

C H Cl Zn

"C ₁₀ H ₁₀ Cl ₆ N ₄ S ₆ Zn ^ C ₅ H ₅ N; calc .: 30.52 2.56 27.07 8.3

found: 30.57 3.01 27.36 8.1

Example 10 Production of zinc bis-C2.2-dimethylthiazolidine-3-carbodithioate)

2 4. \ - (CHO ₉ + 2CS ₉ + Zn (OAc) ₉ - ->

y ^ ^{ä ddd} isopropanol H triethylamine

+ ² Cl "

C (S) S

Zn

A mixture of 30 ml of isopropanol and 101 g (1 mol) of triethylamine is added with stirring and cooling at 10 ^° C. with 76.8 g (0.5 mol) of 2,2-dimethylthiazolidine hydrochloride (preparation according to B. Sweetman et al ., J. Med. Chem. 12 (1969), p. 888). Furthermore, 38 g (0.5 mol) of carbon disulfide are gradually added. Then 45.8 g (0.25 mol) of anhydrous zinc acetate are added. The batch is left to stand at room temperature overnight. The precipitate formed is then filtered off, washed twice with 1 liter of water each time and air-dried. This gives 80.5 g of the yellow product with a p.p. 148 to 153 ° C. (decomposition).

C H

calc .: 32.04 4.45

pf .: 31.51 4.70

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example

Manufacture of zinc-bis- / spiro- (cyclohexane-1, ^ '- oxazolidine) -3-car "bo dithio at7

Oo

+ 2 CS ₂ + Zn (OAc) ₂

Isopropanol triethylamine

G (S) S

Zn

A mixture of 500 g of isopropanol and 50.5 g (0.5 mol) of triethylamine is added at 10 to 20 ^° C. while stirring with 38 g (0.5 mol) of carbon disulfide. The resulting solution is mixed with 70.5 g (0.5 mol) of spiro (cyclohexane-1,2'-oxazolidine) (preparation according to A. Cope and E. Hancock, J. Am. Chera. Soc. 64 (1942 ), Page 1503). Then 46 g (0.25 mol) of anhydrous zinc acetate are added. The reaction mixture is stirred for 4 hours at room temperature and left to stand overnight. The precipitate formed is filtered off. This gives 97.4 g of the desired Carbodithioats of mp. 198-200 ⁰ C (decomposition). A sample which was dissolved in hot dimethyl sulfoxide and precipitated by adding methanol has a melting point of 212 to 213 ° C. and the following analytical values

C ₁₈ H ₂₈ N ₂ O ₂ S ₄ Zn; ber .:

gef.i

σ 43 5 H 5 N 1 Zn 15th 43, 80. 5 , 63 5 , 63 1 3, 90 42, , 4T , 75 2,

A modified and much less advantageous process for the preparation of the zinc salts according to the invention is, as mentioned, that the desired compound from the complex reaction product of the amino alkanol (or aminomercaptane) ,, formaldehyde, carbon disulfide and zinc salt precursor by a time-consuming, im generally isolated solvent extraction giving relatively poor yields. Hereinafter, a typical such production method is described, is obtained in which the compound of Example 1, ie, zinc-bis- (3-oxazolidine carbodithioate) according to the modified operation.

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Example 12

A solution is added of 183 g (3 mol) of ethanolamine in 600 ml of water with rapid stirring at 10 to 20 ⁰ C was added dropwise 243 g (3 moles) 37prozentiger formaldehyde solution. Stir the reaction mixture for 1 hour at 50 to 60 ⁰ C. then added at 5 to 1O ⁰ C was added dropwise 228 g (3 moles) of carbon disulfide added. Stirring is continued for 2 more hours at 40 to 5O ⁰ C. The reaction mixture is then introduced into a solution of 432 g (1.5 mol) of zinc sulfate heptahydrate in 900 ml of water at room temperature with rapid stirring. The precipitate formed is filtered off, washed with water and air-dried. This gives 143.3 g of a white crystalline product (accelerator No. 15) with a melting point of 162 to 175 ^° C. (decomposition); the conversion is 26.4 5 ^. ·

7 g are dissolved for further purification. of the aforementioned crude product using a steam bath in 66 ml of dimethylformamide. After cooling and diluting with 20 ml of 95 percent ethanol, it is filtered. 5 g of a white crystalline product of melting point 218 to 220 ^° C. (decomposition) are obtained (after air drying). These 5 g of white crystals are suspended in 300 ml of boiling chloroform 95prozentigem ml ethanol diluted After filtration 221 is obtained 2.2 g of white crystalline product of melting point to 222 ⁰ C (decomposed); the related to the originally used compounds conversion is 8 3 # · the product has the following analytical _values:..? _

C H N Zn

C ₈ H ₁₂ N ₂ O ₂ S ₄ Zn; calc .: 26.56 3.32 7.75 18.10

Found: 26.73 3.44 7.96 17.46

Example 13

Preparation of the pyridine adduct of zinc bis (2-methyl-2-phenyloxazolidine-3-carbodithioate)

This adduct is prepared as described for the tripyridine adduct of zinc bis / 2- (3-ethoxy-4-hydroxyphenyl) oxazolidine-3- carbodithioate / (compound no. 6, example 6) Bafeei

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However, if acetophenone is used instead of 3-ethoxy-4-hydroxybenzaldehyde. After the reaction has ended, the reaction mixture is evaporated to dryness and the solid residue is washed thoroughly with hot isopropanol. The product has a melting point of 169 to 173 ^° C. (decomposition) and. is identified by its IR spectrum. It is contaminated with some zinc acetate.

Example 14 Preparation of zinc bis ( 4-morpholine carbodithioate)

+ 2CS ₉ + Zn (OAc) ₉

$ 95 ethanol

CS

Zn

Man. added a mixture of 22 g (0 _y 1 mol) of zinc acetate dihydrate and 15.2 g (0.2 mol) of carbon disulfide in 400 ml of 95 percent ethanol slowly with stirring with 17/4 g (0.2 mol) of morpholine at 20 to 40 ⁰ C. After filtering the reaction mixture, 34.6 g of the desired solid product, which ^{does not melt up to 300 °} C., are obtained. A portion of the product is dissolved in chloroform and reprecipitated with hexane.

C H N ■ Zn

C ₁₀ H ₁₆ N ₂ O ₂ S ₄ Zn? calc .: 30.82 4.11 7 * 19 16.80

found: " 31» 40 4.39 7.30 16.00

The aforementioned product is sold in CA. 54, 19004 (1960; Russian patent 127 387 from 3/25/60) referred to as a rubber accelerator. No physical properties are given in the abstract; however, the above analytical values confirm the composition of the product »

B is ρ ie I _- J5. "

Pvridine adduct of zinc-bis-f 2-phenyl oxazolidine-3-carbodit3iioat)

+ 2 CS ₂ + Zn (OAc) ₂ +

C (S) S

Zn-C ₅ H ₅ N

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The starting compound N- (2-hydroxyethyl) benzalamine (i.e. the Tautomers of 2-phenyloxazolidine) are made from benzaldehyde and ethanolamine according to the method of L. Baasch and H. Hanninen, J. Amer. Chem. Soc. 72 (1950), page 3673.

A solution of 131 g (0.88 mol) of N- (2-hydroxyethyl) - benzalamine, 68 g (0.88 mol) of carbon disulfide and 300 ml of pyridine is mixed with 81 g (0.44 mol) of anhydrous zinc acetate while stirring . After stirring for 5 hours at 25 to 45 ⁰ C and the precipitate formed is filtered off, washed twice with 700 ml 95prozentigem ethanol and filtered again. 217.7 g of the desired product, which has a decomposition point of 196 to 200 ° C., are obtained.

CH N Zn

^C 20 ^H 20 ^N 2 ° 2 ^S 4 ^Zn ' ^C 5 ^H 5 ^{N; over # i 5O '67 4} ' ^{22 7} ' ⁹ ° ¹¹ ' ⁰⁵

found: 50.75 4.33 7.78 11.02

example

16

Zinc-bis- (2-phenyloxazolidine-3 ~ car.bodithioate)

C (S) S

C (S) S

Zn

A 50 g sample of the pyridine adduct from Example 15 is heated to 110 to 115 ^° C. for 17 hours at a pressure of 1 torr. This gives 44.7 g of the desired product which melts ^{at 133 to 186 ° C. with decomposition.} The IR spectrum and the subsequent analysis show that the product contains only 5 $ residual pyridine.

C H Zn

calc. (for 5 # pyridine containing product): 48.29 4.02 12.10 Found: - 47.84 4.21 12.17

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Example 17

Pyridine adduct of zinc-bis- / 2- (p-chlorophenyl) -oxazolidine-3- -carbodithioate 7

P-CIC ₆ H ₄ CH = NCH ₂ Ch ₂ OH

^C 6 ^H 4 ^C1 (p)

The above tautomeric mixture (melting point 70 to 73 ° C.) is produced p-chlorobenzaldehyde and ethanolamine using the same method, which for the ο-ChIo ri so mere by L. Daasch and H. Hanninen, J. Amer. Chem. Soc. 72 (1950), page 3673.

C ₆ H ₄ -p-Cl + 2CS ₂ + Zn (OAc) ₂ + C ₅ H ₅ N

ZnX ₅ H ₅ N 2

A solution of 47 g (0.62 mol) of carbon disulfide in 200 ml of pyridine is mixed with II4 g (0.62 mol) of the aforementioned mixture of 2- (p-chlorophenyl) oxazolidine and the Schiff's base. The batch is left to stand at room temperature overnight. Then distilling the pyridine starting at a pressure of 0.5 torr and a pot temperature of 6O ⁰ C. 203 g of a brown, sticky, solid substance remain as residue. The crude residue is washed thoroughly with water and then with isopropanol. This gives 132 g of the desired product which ^{melts at 119 to 132 °} C. with decomposition. The product contains 6 # nitrogen; the theoretical nitrogen content is 6.35 ^.

Example 18

Pyridine adduct of zinc bis Z2- (1-ethylpentyl) oxazolidine-3-carbodithioate 7

CH ₃ + 2CS ₂ + Zn (OAc)

C ₂ H ₅ PH (CH ₂ )
'C (S) S

Zn-C ₅ H ₅ N

The starting material, i.e. the tautomeric mixture of the oxazolidine and the Schiff's view base, is made from 2-ethylhexanol and

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nolamine produced in benzene by azeotropic distillation of water. The tautomeric mixture is distilled (boiling point 100 to 1O2 ° G / 3 Torr), before they are implemented with OSg.

A cooled solution of 127 g (0.74 mol) of the aforementioned a-Ci-lthylpentylJ-oxazolidins / Schiff's base in 150 ml of pyridine is mixed with 57 g (0.74 mol) of carbon disulfide and then with 68 g (0.37 Mol) water-free zinc acetate added * After stirring for 30 minutes at 45 to 50 ⁰ G, the reaction mixture is ^{freed from the volatile constituents at 60 0} G / 1 Torr. 225 g of a semi-solid product remain as residue.

G H N Zn

^C 22 ^H 40 ^N 2 ° 2 ^S 4 ^{Zn # G} 5 ^H 5 ^{Ni ber #: 5} ° ^{'91 7} ' ^{0T 6} » ^{60 t0 '28}

found i 50.21 7.43 5.79 10.53

Eg 1 19

Pyridine adduct of zinc-bis- (S-methyl ^ -trichloromethyloxazolidine- -3-carbodithioate)

CH ₃ CH (OH) CHgNH ₂ + CGl ₃ CHO ^ - / \ - <jCl

250 ml of glacial acetic acid are added while stirring and cooling with 90 g (1.2 mol) of i-affiino-2-propanol. After adding. 177 g (1 mol * 2) chloral the reaction mixture is heated for 1 hour at 45 to 5O ⁰ C. The acetic acid is distilled off at a pressure of 5 Torr and a 'pot temperature of 45 ⁰ C. The oily distillation residue (236 g) is diluted with 300 ml of hexane and cooled to 1O ⁰ C. The precipitate is filtered off. In this case, 46 is obtained 36 g of crude 5-methyl-2-trichlormethyloxazolidin from Pp. ⁰ to 54 C. A small sample points after twice from hexane Ümkristallisation a Pp. 59-62 ⁰ C.

CHN

C ₅ HgCl ₃ NOi animal t 29.34 3.91 6.85 found: 29.77 4.00 7.10

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An Nff band appears in the IR spectrum.

CG1 .. + 2 C3 ₂ + Zn (0Ac)

Zn-O ₅ H ₅ N

A mixture of 237 g (3 mol) of pyridine, 38 g (0.5 mol) of carbon disulfide, 45.9 g (0.25 mol) of anhydrous zinc acetate and 102.3 g (0.5 mol) of 5-methyl- 2-trichloromethyloxazolidine for 3 hours at 45 ^° C. The reaction mixture is then left to stand overnight at room temperature and then diluted with 1 liter of water. The insoluble oil layer is separated off, treated with 200 ml of hot isopropanol and cooled to 5 ^° C. The precipitate is filtered off and gives 103.5 g of crude product. This is dissolved in 450 ml of hot pyridine; at 10 ⁰ C, the pyridine solution is diluted with 1500 ml of water and filtered · Here, g is 53 »8 is the desired product, which at 104 to 133 ° C melt (under Pyridinverlust and decomposition).

C H N Zn

C ₁₂ H ₁₄ Cl ₆ N ₂ O ₂ S ₄ ZnX ₅ H ₅ Nj calc.s 29.00 2.70 5.97 9.30

found: 29.29 2.91 6.17 9.70

example

20th

Zinc bis (5-methyl-2-trichloromethyloxazolidine-3-carbodithioate)

CCl

+ 2CS ₂ + Zn (OAc) ₂

Cl-

Zn

A mixture of 412 g (4 mol) of triethylamine, 60.8 g (0.8 mol) of carbon disulfide, 73.2 g (0.4 mol) of anhydrous zinc acetate and 163.6 g (0.8 mol) of 5- methyl-2-trichlormethylbxazolidin 1 hour at 40 ⁰ C. the R Saf ions mixture is allowed to stand at room temperature overnight, diluted with water and trated fil * This gives 417.8 g of the crude product

- »18 - *

309 8 81/1202

I.R. 1854-A

which sinters at 89 ⁰ C and melts at 128 to 15O ⁰ C with decomposition. Extraction with chloroform and repeated recrystallization from benzene yielded an analytical sample, melting at 170 to 1-76 ⁰ C with decomposition.

N Zn

C ₁₂ H ₁₄ Cl ₆ N ₂ O ₂ S ₄ Zn; calc .: 4.48 10.47

found: 4.30 10.16

example

21

Zinc bis (4 _t 4-dimethyloxazolidine-3-carbodithioate)

2 (CH ₃ ) ₂ CCH ₂ OH + 2 HCHO + 2 CS ₂ + Zn (OAc) ₂

NH

Zn

A solution is added of 89.2 g (1 mol) of 2-amino-2-methyl-1-propanol in 600 ml isopropanol at a temperature of 45 "to 64 ⁰ C with 30 g (1 mol) of paraformaldehyde. After the is all paraformaldehyde dissolved, the mixture is cooled to 12 ⁰ C and admixed with 92 g (0.5 mol) of anhydrous zinc acetate and 76 g (1 mol) of carbon disulfide. the reaction mixture for 6 hours at 45 to 50 ⁰ C. Filtration at 5 ^° C. gives 152.6 g of the desired product, which ^{melts with decomposition at 209 to 211 °} C. A sample brought to crystallization from benzene has the following analytical values:

C H N Zn

C ₁₂ H ₂₀ N ₂ O ₂ S ₄ Zn; calc .: 34.50 4.79 6.71 15.67

Found: 34.92 4.91 6.62 15.47

example

22nd

Zinc ~ bis (5-phenyl-3-oxazolidine carbodithioate)

0 ■

2 C ₆ H ₅ CH-CH ₂ + 2 (CH ₂ O) _x + 2 CS ₂ + Zn (OCCH ₃ ) 2 OH NH ₂ .

- 19 -

I IS

0 IL H

X ^Ci

H H

Zn 2

3 0 9-881 / 1202

So

500 ml of isopropanol are added, 30 g (1 mol) of paraformaldehyde and 137 g (1 mol) of 2-amino-i-phenylethanol. The resulting mixture "was stirred heated to 50 ⁰ C and. After all the solid components have dissolved, the solution is stirred an additional 30 minutes at 5O ⁰ C. Then is added to the, cooled to 35 ° C solution containing 68.7 g ( 0.375 mol) of anhydrous zinc acetate and 76 g (1 mol) of carbon disulfide. In a few minutes, solids separate; further isopropanol (400 ml) is added and the mixture is stirred thoroughly. After heating for two hours at 55 ° C., the mixture is cooled and filtered The solid fractions formed are washed several times with water in a Waring mixer (Waring-Blendor) and then air-dried overnight, giving 184 g (yield 95%) of the desired product with a melting point of 220 to 223 ^° C., the IR -Spectrum of the product corresponds to the

Structure. N Zn η TT _Γ'ΤΤ_Γ ¹ 'Η'
6 5 "Τ ι 2
O _n / ^^ Zn C ₂₀ H ₂₀ N ₂ O ₂ S ₄ Zn; calc .: 5.45 12.13 H Cd ₃ 2 found: 4.90 12.73 B e i s ρ i el 23 Zinc bis (5-phenyl-2-trichloromethyl-3-oxazolidine carbodithioate) OC ^ H, - <
Il 0 5 rtTT / - (DD
> ri — oup H "CCl ₃

A mixture of equimolar proportions of chloral, glacial acetic acid and 2-amino-1-phenylethanol in benzene is refluxed using a Dean-Stark trap until no more water is formed. The benzene is then distilled off and the distillation residue is rubbed with ether and filtered. Evaporation of the filtrate gives the crude 5-phenyl-2-trichlormethyloxazolidin of melting point 58 to 64 ⁰ C. Its structure. Is the IR spectrum and by elemental analysis of a sample, which melts after recrystallization from ether at 67 to 69 ⁰ O, confirmed.

- 20 -

30 9 881/1202

A mixture of 30.3 g (0.3 mol) of triethylamine, 18.3 g (0.1 mol) of zinc acetate, 55 g (0.206 mol) of 5-phenyl-2-trichloromethyloxazolidine and 15.6 g (0.206 mol) Carbon disulfide is stirred for 17 hours at room temperature and then heated ^{to 50 ° C. for 3 hours.} After the volatile components have been distilled off at 50 ° C./25 Torr, a reddish-amber-colored semi-solid substance is obtained. This is dissolved in methanol and the solution obtained is introduced into water with vigorous stirring. The solid components are filtered off, air-dried and redissolved in benzene. After drying the solution over magnesium sulfate, filtering the mixture and evaporating the solvent, 37 g (yield 58 #) of the desired product with a boiling point of 91 to 93 ° C. are obtained; its IR spectrum corresponds to the structure.

^C 22 ^H 18 ^Cl 6 ^N 2 ° 2 ^S 4 ^{Zn; over # i} 3.74

found: 3.86

When using the compounds according to the invention as accelerators for the vulcanization of elastomers, in particular ethylene / propylene / diene elastomers (EPDM elastomers), about 0.5 to 5 parts by weight (preferably 1.5 to 4 parts by weight) are generally used per 100 parts by weight of the elastomer Parts by weight) of the accelerator compound, generally with about 0.5 to 3 parts by weight of sulfur as a vulcanizing agent. The accelerator composition is blended into the elastomer along with the sulfur and other falultative modifying additives such as carbon black, stearic acid, zinc oxide, naphthenic oil and other commercially available additives. The elastomer is then cured in a conventional manner (vulcanized) ', it is heated by about 10 seconds to 1 hour at about 150-232 ⁰ C (about 300 to 45O ⁰ P). In general, heated for approximately 10 to 40 minutes at about 150 177 ⁰ C (about 300 to 35O ⁰ P).

It has been found that the compounds according to the invention not only inhibit blooming in the case of cured elastomers, but usually also have an increased accelerating effect. This is reflected in a considerable increase in tensile strength and the

- 21 -

30988 1/120 2

Modulus of the elastomer. The increase results from comparative tests carried out under the same conditions, in which other accelerators are used in corresponding concentrations . The results that can be achieved according to the invention, in particular the unexpected non-blooming behavior, are illustrated by the following examples. In the context of these examples , the vulcanization of a typical EPDM elastomer is investigated using both accelerators according to the invention and comparative accelerator compositions. The following approach is used, the proportions (parts by weight) of the components being based on 100 parts by weight of the elastomer.

Parts by weight

EPDM elastomer (ethylene / propylene / dicyclopentadiene terpolymer) 100

napthenbasisch.es oil 50

Carbon Black (PEP) 100 Zinc Oxide 5

2-mercaptobenzothiazole 0.5

Stearic acid 2 Sulfur different

(0.5 and 2)

Accelerators different

(2 and 4)

The hardening of the vulcanizate is carried out at 160 ⁰ C (32O ⁰ P); for test purposes, samples are taken at intervals of 5, 10, 20, 30, 40 and 60 minutes.

The various specific compounds tested as accelerators are listed in Table I below. the Accelerators No. 1 to 9, 16, 13 to 23, 25 and 26 are according to the invention. Accelerators No. 1, 2, 3, 4, 8, 18, 22 and 23. The comparative accelerators tested include zinc dithiocarbamates, the structure of which is somewhat similar to that of the compounds according to the invention; the accelerator No. 10 is, for example, a commercially available "ultra-accelerator" for Elastomers Other salts of dithiocarbamic acid, such as the

- 22 -

309881/120 2

quicker nos. 12 and 17, as well as zinc salts of other acids, such as the accelerator No. 11, are also known accelerators dar; two of these accelerators are commercial products. Furthermore, thiuram disulfides (e.g. accelerator No. 13) are ultra-accelerators, which in the presence of zinc oxide during the vulcanization process converted into the corresponding zinc dithiocarbarate (W; S. Scheele et al., Rubber.Chem. and Techn., 31 (1958), page 315? Kautschuk und Gummi 11 (1958), page 51; the Accelerator No. 13 forms e.g. zinc dimethyldithiocarbamate and zinc diethyldithiocarbamate). The physical values obtained when testing the efflorescence are shown in Tables II and III.

The results show that the known accelerators Nos. 10 to 13 and 17, in contrast to the accelerators according to the invention, lead to efflorescence. Efflorescence is also observed when using spiro compounds or 4,4-disubstituted compounds (represented by accelerators no. 14 and 24, respectively) and the zinc salt of the reaction product of ethanolamine, formaldehyde and carbon disulfide (described in US Pat. No. 3,674,701; Accelerator No. 15). The spiro compound also does not have a very high accelerating activity. It turns out that the compounds according to the invention are not only effective non-blooming accelerators, but in several cases even act more rapidly than the commercially available ultra-accelerators; this is shown, for example, by a comparison of: No. 1 with No. 12 and No. 13 (hardening at 160 ^° C. or 320 ^° F); No. 2 with No. 13 (curing in both cases at approximately 152 ⁰ O or 3O5 ° F)..;
No. 3, No. 8, No. 22 and No. 23 with No. 10, No. 12 and No. 13.

- 23 -

309881/1202

Table I Specific Accelerators Tested on an EPDM Elastomer Example Accelerators

No. No.

1 zinc bis (3-oxazolidine carbodithioate) 2 zinc bis (2-trichloromethyl-3-oxazolidine

carbodithioate

3 pyridine adduct of zinc-bis- (2-trichloro-

methyl 3-oxazolidine carbodithioate) 4 'zinc bis (2,2-dimethyloxazolidine-3-carbo--

dithioate)

5 pyridine adduct of zinc-bis- / 2- (p-dimethyl-

aminophenyl) oxazolidine-3-carbodithioate / 6 tripyridine adduct of zinc-bis- / 2- (3-ethoxy-

-4-hydroxyphenyl) -o xazo lid in-3-c arbo dithioay

Ί Zinc-biB- (thiazolidine-3-carldodithioate)

8 Dipyridine adduct of zinc-bis - / "(2-trichloro-

methyl) thiazolidine-3-carbodithioate7 9 zinc bis (2,2-dimethylthiazolidine-3-

-carbodithioate)

Zinc bis (diethyl dithiocarbamate)

Zinc bis (O, O-dibutyl phosphorodithioate)

Tellurium tetrakis (diethyldithiocarbamate)

Mixture of tetramethylthiuram disulfide and Tetraethylthiuram disulfide (3: 1) 14 zinc-bis- / spiro- (cyclohexane-1,2'-oxazoli-

din) -3-carbodithioate /

15 Zinc salt of the reaction product of etha

nolamine, formaldehyde and carbon disulfide 16 pyridine adduct of zinc-bis- (2-methyl-2-

-phenyloxazolidine-3-carbodithioate)

Zinc bis (4-morpholine carbodithioate)

Pyridine adduct of zinc bis (2-phenyloxazolidine-3-carbodithioate)

Zinc bis (2-phenyloxazolidine-3-carbon arbodithioate)

Pyridine adduct of zinc bis- / 2- (p-chlorophenyl) oxazolidine-3-carbodithioate / 21 pyridine adduct of zinc-bis- ^ 2- (1-ethylpen-

tyl) oxazolidine-3-carbodithioate /

22 pyridine adduct of zinc bis (5-methyl-2-tri-

chloromethyl oxazolidine-3-carbodithioate)

- 24 -

309881/1202

14th 17th 15th 18th 16 19th 17th 20th

Table I (continued)

Example accelerator
No. No.

20 23 _Zinc-bis- (5-methyl-2-trichloromethyl-

bxazolidine) -3-carbodithioate

»21 - 24 zinc-bis- (4,4-dimethyloxazolidine-3-

-carbodithioate)

22 25 zinc-bis- (5-phenyl-3-oxazolidinecarbo-

dithioate)

26 zinc bisC phenylatric

oxazolidine carbodithioate)

- 25 -

309881/1202

IE 1854-A Table II

Example accelerator vulcanizate (16O ⁰ C) ^'a' with 2 parts of accelerator and 2 parts of sulfur

(b) _N _ (. each per 100 parts by weight of elastomer)

^^ Tensile strength (kp / cnuO 200fo-Modul (kp / cm ^) efflorescence after at curing time (min) at curing time (min) 1 to 2 weeks 5 10 20 40 60 5. 10 20 40

97.7 147.6 185.6 189.8 195.1 35.2 51.0 75.9 98.4 none

91.4 152.9 184.5 196.9 198.6 59.8 ^(d) 9i, 4®l58.2 ^ 95.1 ^(d) none 137.1 162.4 165.2 174.0 171.6 52 , 7 73.8 94.9 103.4. no

61.5 82.6 112.5 144.1 - 28.1 33.4 56.3 none

62.6 87.9 119.5 151.2 161.7 31.6 42.2 59.8 76.6 none

43.6 72.4 108.3 172.3 179.3 24.6 38.7 63.3 112.5 none 112.5 158.2 182.8 196.9 203.9 47.5 70.3 94.9 110.7 none

52.7 70.3 .98.4 124.8 13 &, 8 28.1 31.6 51.0 61.5 none

93.2 152.9 196.9 207.4 193.4 38.7 ^ 59, ^ 96.7 ^ 116.0, -

59.8 ^ 96.7 ^ 140.6 "182.8 ^W medium

48.5 80.2 140.6 175.0 175.0. 21.1 35.2 63.3 85.8 easy *

65.4 116.0 158.2 188.1 186.3 25.3 ^ 42.2 ^ 67.5 ^ 87.2 ^

40, ö ^w 68.4 ^ 105.5 ^ 137, ™ easy ·

72.1 147.6 182.8 186.3 189.8 31.6 70.3 91.4 117.7 strong

Battle 86.1 152.9 174.0 196.9 bad 56.3 ^ 98.4®140.6 ^ strong

bad bad 82.6 86.1 103.7 bad slides 59.8 ^ 66.8® easy

95.6 161.7 182.8 193.4 184.5 38.7 66.8 90.7 99.8 easy 87.9 133.6 181.0 188.1 186.3 36.9 '56.3 84.4 119.5 none

116.0 154.0 175.8 179.3 189.1 46.4 66.8 84.4 94.9 none n>

-26'- 'oo

cn • K)

1
₂ (c) 2
3 3 4th 5 7th 6th 6th 7th 8th 8th 9 9 10 10 - 11 _ 12th - 309881 U
₁₃ (e>
14th
15th 11
12th *%.
_λ 16 13th 202 18th 15th

I.E. 1854-A

Table II (continued)

Accelerator example vulcanizate (160 ° C) ^ ^a 'with 2 parts accelerator and 2 parts sulfur

No.

19th
20th
21
22nd
23
24
25th
26th

No.

16 17 18

19 20 21 22 23

(, each per 100 parts by weight of elastomer)

Tensile strength (kp / cm)

at curing time (min)

5 10 20 40 bO

80.9 126.6 151.2 158.2 165.2

89.3,141.3 168.7 175.0 172.9

85.1 137.1 174.0 178.6 191.6

129.3 159.6 172.3 178.6 183.5

143.8 170.1 170.5 169.4,182.8 113.2 161.0 172.3 189.1 189.8

52.7 95.6 139.9 151.2 158.2

120.9 154.7 172.3 172.3 182.8

200 ^ module (kp / cm ² )
at curing time (min)

Efflorescence after
up to 2 weeks

5 10 20th 40 no 34.4 56.3 81.6 98.4 no 38.7 60.8 78.7 91.4 no 35.2 53.4 78.0 101.9 no 52.7 71.0 86.1 99.8 no 66.8 82.6 102.7 116.7 strong 45.7 64.3 98.4 118.1 no 28.1 46.4 69.6 91.4 no 56.9 75.2 97.0 112.5

Ca): with the exception of the samples marked with (c); (b) s accelerator designations see Table I;

(c) s, the curing temperature is about 151.7 ⁰ C (3O5 ° P> instead of 16O ⁰ C (32O ⁰ P); 300 ^ module.

- 27 "-.

N) CO NJ OO cn NJ

I.E. Ί854-Α

Table III (a)

Accelerator example vulcanizate (160 C) ^v 'with 4 parts of Be slimy and 0.5 parts of sulfur

No.

10

No.

(, each per 100 parts by weight of elastomer)

1 2 ₂ (c) 3 4th 5 6th 6th 7th 8th 8th 9

11 - 12th - 13th _ CO ₁₃ (o) - O
CO 14th 11 00
OO 15th 12th -α 16 13th —Α 17th H Κ » O tv)

Tensile strength (kp / cm) at curing time (min) 5 TO 20 40

60

54.8 90.7 133.6 140.6 139.2

56.3 96.7 138.8 168.7 172.3

71.0 131.8 146.2 158.2 149.0

42.2 57.7 64.0 62.6 62.6 49.2 74.5 102.7 106.1

70.3 108.9 141.3 137.1 131.5

84.4 139.2 161.7 167.0-155.4 33.8,

55.5 72.0 106.1 132.9

54.1 101.9 127.9 130.0

42.2 147.7 177.2 172.9 bad 31.6 152.9 175.8 bad bad bad 33.4

54.5 87.9 108.9 101.9

86.5 119.5 140.6 135.3

bad bad 44.3 66.1

200fo module (kp / cm 20th (min) Efflorescence after at curing time 48.5 40 1 to 2 weeks 5 10 L) fdj : ⁵² ' ⁷ , "; ²¹ 'V ⁰ ' ² V 66.8 4i6, O < ^d > no 40.4 ^(d) 59.8 ^(c 31.6 67.5 no 35.2 52.7 35.2 28.1 no 21.1 24.6 49.2 no 24.6 no

33.8 / ^ 54.573) 69.% 70.
54.8 ^W 87.2 ^ 105.5 ^ 108.9

124.8 24.6 30.9 42.2 52.7

126.6 21.8 42.9 48.5 53.4

175.8 19.0 56.3 77.3 79.1

175.8 poor 24.6®100.2®126.6

35.2 bad bad bad 24.6

110.4 26.7 42.2 45.7 45.7

144.1 35.2 48.5 59.8 61.5

73.8 's ± Q really bad 17.6 28.1

- 28 - none

strong

easy

middle

strong

strong

easy

easy

no

easy

I.E. 1854-A

T a Tj e 1 1 e III (continued) (a)

Accelerator example vulcanizate (160 C) ^ '' with 4 parts accelerator and 0.5 part sulfur

No.

No.

18th 15th 20th 17th 21 18th 22nd 19th 23 20th 24 21 26th 23

(each per 100 parts by weight of elastomer)

Tensile strength (kp / cm) at curing time (min)

10

20th

60

87.9 116.0 120.2 114.6 118.8

87.9 113.9 119.5 111.8 111.1

77.3 112.5 130.8 128.6 133.6 102.7 133.6 144.1 140.6 132.9

92.1 129.3 147.7 143.4 157.5

81.6 128.3 144.1 154.0 149.4

91.4 119.5 126.6 117.7 117.7

200 ^ module (kp / cm) efflorescence after
"with curing time (min) 1 to 2 weeks

5. 10 20th 40 none to trace: 38.7 51.0 51.0 51.0 no 42.2 46.4 49.9 49.2 no 35.2 45.7 54.8 53.4 no 40.1 56.3 63.3 63.3 no 38.7 55.5 70.3 73.1 strong 35.2 56.3 66.8 66.8 no 41.5 56.3 59.1 59.8

(a): with the exception of the samples marked with (c); (b): Accelerator designations see Table I;

(c) the curing temperature is about 151.7 ⁰ C (305 ⁰ P) instead of 160 ⁰ C (320 ⁰ P);

Q (d): 300 # module.
to

NJ
O
NJ

- 29 - ■ CO K) OO

Claims (1)

Claim e Zn. (C ₅ H ₅ N) _n in which X is a sulfur or oxygen atom, R, H, 2 1 R and R, independently of one another, each represent a hydrogen atom, a lower alkyl radical, a trichloromethyl group, a phenyl group or a substituted phenyl group with one or more substituents from the group NRR, OH, OR and Cl, C ₅ H ₅ N is a pyridium molecule and η is an integer from 0-5. 2 » Compounds according to claim 1, characterized in that X is a sulfur atom. 3. Compounds according to claim 1, characterized in that X is an oxygen atom. 4 · Compounds according to claim 1, characterized in that R, 1 2 λ R, R and R ^J each represent a hydrogen atom and X represents an oxygen atom. 5. Compounds according to claim 1, characterized in that R represents a hydrogen atom, R represents a trichloromethyl group, R and R ^J each represent a hydrogen atom and X is an oxygen atom. 6. A compound according to claim 5, characterized in that η is 0 . 7 · Connection according to claim 5, characterized in that η - 30 - 309881/1202 I.E. 1854-A 1 is. 8. Compounds according to claim 1, characterized in that R 1 2 λ • and R each represent a methyl group, R and R each represent a hydrogen atom and X is an oxygen atom. 9 · Compounds according to claim 1, characterized in that R 2 1 and R each represent a hydrogen atom, R a trichloromethyl group R represents a methyl group and X is a sulfur atom. 10. Compounds according to claim 1, characterized in that R, 2 ■} 1 R and E ^J each represent a hydrogen atom, R represents a trichloromethyl group and X is a sulfur atom. 11. -Connection 2 is. according to claim 10, characterized in that η 12. Compounds according to claim 1, characterized in that R 2 1 and R each represent a hydrogen atom, R a trichloro represents methyl group, R-oxygen atom means. is a methyl group and X is a 13 Process for curing an ethylene / propylene / diene elastomer, wherein one includes the elastomer composition which includes sulfur, a vulcanization accelerator and other rubber compounding ingredients are added, cures at elevated temperature, characterized in that the accelerator is a Compound of the general formula Zn. (C ₅ H ₅ N) _n in which X denotes a sulfur or oxygen atom, R, R, 'independently of one another are each a hydrogen atom, - 31 - R ² and 309881/1202 I.R. 1854-A a lower alkyl radical, a trichloromethyl group, a phenyl group or a substituted phenyl group with one or more substituents from the group NRR, OH, OR and Cl represent, Ο, -Η, -Ν means a pyridine molecule and η means a whole Number from 0 to 5 is used. 14 · The method according to claim 13 »characterized in that X is a Is sulfur atom. 15. The method according to claim 13 »characterized in that X is a Is oxygen atom. 16. The method according to claim 13 »characterized in that R, R, R and R ^J each represent a hydrogen atom and X is an oxygen atom. 17. The method according to claim 13 »characterized in that R represents a hydrogen atom, R represents a trichloromethyl group, R and R ^J each represent a hydrogen atom and X is an oxygen atom. 18. The method according to claim 17, characterized in that η 0 is. 19. The method according to claim 17, characterized in that η 1 is. 20. The method according to claim 13, characterized in that R 1 2 3 and R each represent a methyl group, R and R each represent represent a hydrogen atom and X is an oxygen atom. 21. The method according to claim I3, characterized in that R represents a hydrogen atom, R represents a trichloromethyl group, R ² and R ^ each represent a hydrogen atom and X is a sulfur atom. - 32 - 30 * 881/1202 I.Rc 1854-A 22. The method according to claim 21 _0, characterized in ₉ that n is 2 «, 23 · Method according to Claim 13 _S, characterized in that R a hydrogen atom, R meant a triehlomethylgrappe 2 ^ represents, R is a hydrogen atom, _p R is a pe beaemtet and X represented an oxygen atom - 33 - 309881/1202