DE2209840A1 - Antioxidants - Google Patents

Description

Antioxidants

Priority: 1. 3 · 1971 - Great Britain

The invention relates to the stabilization of rubbers against oxidation through the use of A © jlderi ~ father of certain aromatic,

ρ -Nitroaoanilines are of value eis AatloscldatlG & aaif ^ l ia rubbers, and in particular therefore «Extraction from the K> iatschuk di.ir> K T-visyn ^ The acyl derivatives, dl ** according to λ © τ £ ^ ΐ:> / jd ^ rg sf ^i: \ cvuet warden, 'beaitzoa ä ^ over Kitrosoaailiaen advantage because oils are few? to discoloration and to? Heating the skin tend to become

209841/1 176

disperse more easily in rubber and have less influence on the processing security of the rubber.

According to the invention, therefore, stabilized rubber compositions are made proposed that contain an Acy.'verbindungen in a stabilizing amount, the acyl compound an acyl derivative of a nitroso compound of the formula

-Q-HO

(D

is where Z is a hydroxyl group or a group of Formula NHH or N (OH) B, where R is an alkyl, alkenyl, Cycloalkyl or aryl group or a substituted derivative thereof, and in which the bensol ring optionally further can be substituted.

The rubber can be a natural rubber or a synthetic rubber »Examples are polymers or mixed polymers, derived from a conjugated diene, such as cifl-polybutadiene, ois-polyisoprene, other polymers of butadiene or isoprene, polymers of 2-chlorobutadiene or copolymers of the aforementioned substances with one another or with isobutene, styrene, acrylonitrile, methyl methacrylate or other well-known polymerizable compounds, used in the manufacture of synthetic rubbers.

The acyl compound can be incorporated into the rubber by any convenient method. For example, it can be mixed on a MEihl »with the unvulcanized rubber alone or with other compounds ¹ known in rubber technology, such as with vulcanization

209841/1176 BAD ORIGINAL

agents, sulfur, vulcanization accelerators, retarders, antiozonants, other antioxidants, propellants, pigments, Fillers and wax The acyl compounds bind of particular Wert sur stabilization of vulcanized Kautechuk-Bueammense tongues

The amount of the aoyl compound used is more appropriate Way between 0.1 and 4.0 wt "- $ and preferably between 0.25 and 2.0 wt .- $ based on the rubber. It can, however larger or smaller amounts can also be used if necessary.

It is assumed that the acyl compounds are different from the Ohinonoxiai- or Chi nonininoxin-taut oma ren derive the nitroso compounds and the formulas

-TV,

.0.Ao RIF ^ /"S.O.Ac HN v # j

\ sssr

have, wherein R bsaltst the meaning given above and Ac stands for an · acyl group * However, the invention is intended through this · theory not be limited.

• ι. ·

Examples of groups represented by H, alkyl groups such as sB Mathyl, ethyl, isopropyl uad a-octyl, alkenyl groups such as oleyl bB, Oycloalkylgruppen _t iB as cyclohexyl, aryl groups such as sB phenyl, p-tolyl, and QR Haphthyl and substituted derivative of the above-mentioned wit β-»ß-hydroxyethyl, p-hydroxyphenyl and p-chlorophonyl.

2098-1 / 1176

ABOUT 6

The preferred aoyl compounds are those derived from Derive hitroso compounds in which X is an alkylaalao group, in particular a methylamine or ethylamino group, or an arylealno group, especially an anilino group, stands·

The acyl group is derived from an aliphatic, unsaturated one aliphatic, oyoloaliphatic, aroaatisohen or heterocyolieohen Mono- or polyarboxylic acid or a substituted one Derive derivative from it. Examples of such acids are Aaeleea- «Sseig-, Leurin-, Beh * n-, Ieobutter-, 3-Ohloropropion-, 1-naphthalene, phenoxy, acrylic, oil, Coals «» alkyl hydrogen carbons (see e.g. ethyl hydrogen carbons), Adipine, alain, sebaoine, itaoon, cyclobutane, oyolohexane, Oyolodeoan-, Kaphthen-, Cyolohexan-i ^ -dicarbon-, Beneoe-, ο », β * and p-nitrobene, p-toluene, p-chlorobenio, 1-baphthoe, Terephthal, Iiophthal, Hikotin, Furoin and Ohinaldine acid.

In those cases in which the acyl group is derived from a polycarbonate derives, one or more of the carbonic acid groups germinate in the formation of the aoyl compound aitvirken

The preferred oarbone cures from which the aoyl groups are derived can be, are alkanoarboxylic acids, which in total • aat 4 to 18 carbon atoms, in particular Laurin and flteaxinsftur ·, cabbage · nslur ·, alkyl- for example ·· Ethyl hydrogen carbon dioxide, a ^ -alkanedic acid from 6 to 12 Carbon atoaea, in particular · adipine, atelain and Sebaoinslture, and Aryl-carbonsturen, for example · Beasoe- • iar · and readily available derivatives thereof, such as s.B. Alkyl «alkoxy or Ohloro substituents having B «asoeetarea.

2098A1 / 1 176

22098A0

Si · acyl group can alternatively «ia®

or another heterocyclic group as * l & * from the Ohloro derivatives have similar acylitration effects such as aoylchloride Examples of such © hloffohetexOeyelisetw? © 3? ~

bonds are cyanuric chloride _t 2 _s and pheophonitrile chloride · In the cases «in d®B © a

chloroheterocyclic compounds api odar very "" active Ghloratoae can contain an ode? mftteare de »seaktivea

Ohloratoae alt der Bitrosoverbindimg tisigeset ^ t w6sä @ n can, if necessary, replace a remaining reaction in the usual way by reaction with alcohols or phenols

The acyl group can also be a

RR ² N «00, where E ^ and S jevoils fesp ^ sa des? represented type, especially alkylersi methyl or ithyl "or Axgrlgn ^ ppen" like

ii

The acyl group can also ^ sa etm® ^ gaiisi ⁱ <3tof Ä acid of sulfur, the RisspSio ^ s ^ des Silieltsaa

Bors to be derived * Examples 13 »aol @ he ÄeyliiMppea siat

Isopropylsulfenylf Be & BOl

p-toluenesulfonyl, phosphorus jl,

(R0) ₂ 0 * P -, 0I ₂ Sl ^ and OHg

Further if necessary

the acyl compound iiad

Isopropyl, n-butyl, isobutyl. 1,

h. © xyl _f as well as substituted ο / Ii ^ yJ s-.pj. _r *> · r.] _for r: .2, cyl and aromatic groups ,, «ie s ^ i * i ^ o yi« Ta tie &f'JIllca »which 2 a group of the formsl Sl ei- ^ r · 1 ( ί »Π) 1 is« wi »d to prevent the Benairlng r.lohu

209841/1176

2203840

If Z is a group of the formula OH, then preferred substituents are alkyl groups, in particular 2 ~ isopropyl-2-methyl, 2,5-dieethyl and 3-entadecyl.

The acyl compounds can be produced in that one the corresponding hitroso compound of formula I with preventive treated with an acid chloride · But other common reactive derivatives of an acid can also be used that give AnIaB on an acyl group. For example an acid anhydride can be used. The reaction will precautionary carried out in the presence of an acid-binding agent, 'and B was particularly in the presence of a weakly basic metal compound such as a.B. Potassium carbonate, calcium hydroxide, Sodium bicarbonate and goose special sodium carbonate. Other acid-binding agents can be used, such as B.B Itealkalia or organic tertiary amines. The nitroso compounds can also be pre-trained «! Metal salts can be used. The former result in a less pure product and the latter are inconvenient to use.

The reaction is conveniently carried out in a solvent carried out, which is about water or a water-insoluble one organic solvent such as e, B. Toluene or ethyl acetate is «The preferred solvents are ever» but heat-resistant solvents, such as 2.B. low allphatic Alcohols, for example methanol and especially ithanol, and ketones, for example »acetone * The best Results are obtained when these solvents are used in admixture with water. The solvent / The water-weight ratio should be approximately 50:50 and 90t10 are * I & ^ preferred temperature range when using this solvent is 10 to 40 ° 0.

An added benefit of using preventive Process conditions is obtained, consists in that the product obtained has a greater thermal stability and is easier to disperse in rubber. At-

20 9 8 Λ 1/1 176

For example, the benzoyl derivative of 4-nitrosodiphenylamine produced in this way is an orange-colored solid that is largely stable ^{up to the vicinity of the melting point of 154 to 156 0 O.} If, however, it is produced under different conditions, the product obtained has a greenish hue. In addition, it can be difficult to disperse in the rubber. Finally, exothermic decomposition can begin at temperatures as low as 40 ° C.

The product is often insoluble in the reaction medium and can isolated by filtration and washed with water to remove inorganic salts. However, if it is in solution Remains «then it can be done by removing the solvent by distillation or, in suitable cases, by precipitation Addition of water to be isolated

The invention will now be explained in more detail by the following examples, in which all parts and percentages are expressed by weight are4 unless otherwise stated

example 1

10 parts of 4-bitrosodiphenylamine are in 125 parts of acetone dissolved «and 12.5 parts of anhydrous sodium carbonate are dissolved admitted. The mixture is stirred mechanically, and 5 * 1 parts Acetate cure anhydride are added. With a response time of 17 hours, the mixture is filtered and the filter cake is washed with 100 parts of acetone. The Piltrat and the Washing Liquids are poured into 600 parts of water, with

11 parts of the desired aoetyl compound precipitate Precipitation is collected, and after drying at 50 ° 0 under reduced pressure it melts at 8? up to 88 ° 0.

Calculated for C ₁₂ H ₀ Ir ₂ O. C ₂ H _x O: carbon 70, C% »hydrogen 5f0 # and nitrogen 11.7%.

2 0 9 8 A 1/1 1 7 6

found! Carbon 70.85ε, hydrogen, 5.1 %, and nitrogen 11.7%.

The process of Example 1 is repeated, with 10 ropes of p-toluenesulfonyl chloride being used instead of the acetic acid a & hj & rids Ysr. In this way 14.6 parts of the desired acyl compound are obtained, which at 150 to 132 ⁰ O sohailst »

Calculated for O ₁₂ HqV ₂ O * 0 ~ HJ30 ₂ »carbon 64.8%, hydrogen 4.54%» nitrogen 7 * 95% and sulfur 9 »1%.

found carbon 65.5%, hydrogen 4.4%, nitrogen 7 * 6% and sulfur β, 5%

Example 3

10 ropes of 4-VitrosodlphenylaBin become Aoeton in 100 ropes dissolved, and 15 ropes anhydrous · potassium carbonate and 6.8 ropes of V.H'-Meethylcarbaeylchlorid are sugesetst. Sas Geaisoh is heated for 30 hours and heated to the highest level and then filtered · The filter cake is washed old Aoeton, and the filtrate and the washing liquids are combined, diluted with water and under reduced pressure Wait until the largest rope of the acetone has escaped and the product precipitates. 6.0 ropes of acetone become obtained, which sohailst at 158 to 160 * 0 (Eersetsung).

Calculated for O ₁₂ HqV ₂ ⁰ * Οκ ^ Ό * carbon 66.9% «hydrogen 5.6% and nitrogen 15.6% ·

found! Carbon 66.9%, hydrogen 5.5% and nitrogen 15.9%.

2 0 9 8 4 1/1176

Topping!> 1 4

The process of Example 1 is repeated) except that 11.6 parts Η, Η'-Diphenylcarbaaylchlorid "are as Acyllerungsalttel Terwendet are 8.1 parts Aoy! Connection with a" melting point of 154 bia 156 ⁰ O (Zersetaung) received ·

Calculated for C ₁₂ HqH ₂ O * O ₁ ZE ₁₀ HO: carbon 76.3%, hydrogen 4.956 and nitrogen 10.7%.

found: carbon 76.4%, hydrogen 4.9% and nitrogen 10.6%.

The procedure of Example 1 is repeated, except that 6.2 parts Zthylchloroforalat be used as Aeylierungsaittel and the reaction time only 1 st amounts "Se are obtained 53 parts Aoylverbindung that schnilst at 84 to 86 O ⁹ ·

Calculated for O ₁₂ HqH ₂ O. OxHeO ₂ ζ carbon 66.7% * hydrogen 5.2% and nitrogen%

found: carbon 67.0%, hydrogen 5.0% and nitrogen 10.5%.

Example 6

10 parts of p-hitrosodiphenylaain are dissolved in 150 parts of acetone, and 15 parts of anhydrous sodium carbonate are dissolved. The Qeaisoh is stirred and ^{cooled to 0 0} O, and a solution of 15 parts of stearoylochloride in 50 parts of acetone is added dropwise. The mixture is allowed to warm to temperature and stirring is continued for a further hour. The solution is then filtered and the filter cake is washed with 1000 parts of acetone.

209841/1176

fall * After drying, it melts at 78 to 80 ⁰ C with decomposition.

Calculated for O ₁₂ HqN ₂ O. Ο ^ Η ,, - Ο J carbon 77.5% »hydrogen 9.6% and nitrogen 6.0%.

found: carbon 78.0%, hydrogen 9.6% and nitrogen 5.5%.

Example 7

10 parts of 4-nitrosodiphenylamine are dissolved in 100 parts of acetone. 10 parts of anhydrous sodium carbonate are added and the mixture is stirred while a solution of 7.3 parts of adipyl chloride in 30 parts of acetone is added The mixture is then filtered. The filter cake is washed with water to dissolve inorganic salts and dried. This gives 9 * 2 parts acyl compound, melting at 159-160 ⁰ C with decomposition.

Calculated for (C ^ ₂ HqN ₂ O) ₂ .OgHgO ₂ t carbon 7i * 1% »hydrogen 5.2% and nitrogen 11.0%.

found! Carbon 70.7%, hydrogen 5 * 5% and nitrogen 10.8%.

Example 8

The procedure of Example 7 is repeated except that 7.1 parts of sebacoyl chloride are used as the acylating agent. 8.9 parts of acyl compound which ^{melts at 136 to 137 g of} C are obtained.

209841/1 176

Calculated for (O ₁₂ HqH ₂ O) ₂ CLj ₀ H ₁₆ Og ι carbon 72.7%, hydrogen 6.1% and nitrogen 10.0%

found carbon 72.6 %, hydrogen 6.0 % and nitrogen 9.9 X.

Example 9

The procedure of Example 7 is repeated using 4.6 ropes Cyanuric chloride can be used as aeylating agent · It 8.6 parts of the desired acyl compound are obtained «

Calculated for (O ₁₂ HqH ₂ O) ₂ . O ₅ H ₅ Oil t carbon 65.9%, hydrogen 3.6% and chlorine 6.9%.

found: carbon 65.8%, hydrogen 5.8% and chlorine

Example 10

Xs become chewy soups with the following assembly produced by mixing on a Zwelwalsenmunle ι

pale crepe rubber 100

Zinc oxide 10

Stearic acid 1 Barium sulfate 75

Sulfur 2.5 OyelofcexylbenstMasyl-eulfenamid 0.5

Antioxidant as specified

The mixtures are vulcanized at 153 * 0 for 20 minutes, and then the Yulkanlsate are in sheet form with a thickness of 0.8 mm tested for anti-inflammatory agent activity, by determining the time in hours required for 2% oxygen to be absorbed by it 100 * 0 required 1st. The Ifooney scorch page a at

7 6

13O ⁰ O are connected to the uimilkanielerten connection using a Hooney-Tiekosiaeter ·, beetlaat · The side in HLnuttn Ct ₁₀ ) * i · Yeretreicht, bit the HooneT-derivation na 10 units over the Kladeettiskosittt ₉ is ■ eseen · The vu <be and the strength of a colouration of the. Xe are the utmost care for local foodstuffs, dl · no anti-clocking means ·! The results show that the intoxication agent of the invention is more effective and less opaque than 4-IlttoeodlphenylphenylaBln, and that they also retain a high proportion of their loading effect after a Lungamltt "oil extract.

2098A1 / 1 176

An * 1 * rxi & »* Λ onm ¹ * tel nothing product
from
example
6th product
from
example
8th product
ron
example
7th Terephthalmic Isophthalic
acid-di-
ester of
p ~ KLtroeo-
^ iph ** nyl—
aein 4-Vltroso-
dipheoyl
amln I. 22098 2 2 V.
2 acid-di-
ester of
5-5itro8O-
aiphenyl- 2 2 t %, absorbed on chew
scnukkohlenwaeeerstofi 21st • 8th
44 9 2 41 6th
52 20984 Hooney-AnvuT Irani aatior
at 130 ^β 0
t ₁₀ (min)
Time in st for the
Lbsorptlon of 2%
oxygen € 0 61 41 36 j
> 40 __ » alefcts l @ ie ^ t
S @ lb easy easy 26th easy
eau intensive
yellowish
prune 176 Φ ^. «BmAmmmmII« ^ Ail''ΙίΦίΑ HJ \ ^ «4 * 1 -
ej j ^ VX ^ f, JCiU-I ¹ IyA ^ ^ p? For WwLt * "
kan ^ sat yellow easy
brownish
yellow LUS
shloräthen. Supervision
weiehgevaehte® F? 0 , ^ i Aeet t-Appaxat
^ 23-1 60 1 ; with one"
divide roluB * Sow 24 st komti ^ iif
110 7olvmx $ ±: <
1 O-Löetyl-
p ~ benso-
quinone 2 as »EiJI- ion ₉ 42 ¥ ©:

The terephthalic acid and isophthalic acid diesters of p-nitrosodiphenjlaain, those used above are obtained by a method similar to Example 7.

Example 11

Kautsohukgemieohe the following composition are on made by a Zwelwalsensühle:

smoked natural plate chew cb.uk 100

3.5

Stearic acid 3 Oven soot for high abrasion 45

aromatic processing oil 5.5

Sulfur 2.5

Cyolohexylbenethiazyl-eulfenamide 0.5 Antioxidant 0 or 2

The mixtures are vulcanized for 20 min at 155 ^° C. and then the vulcanizates in the form of plates with a thickness of 0.8 mm are tested for antioxidant activity as in the example. The results given below show that the antioxidants according to the invention only slightly lose their antioxidant effect when they are extracted. In some cases, the antioxidant effect is even improved.

209841/1176

ro CD CD CO

«33

Antioxidants nothing Bensoyl
derivative
▼ on 4-mtro-
80-diphonyl- icetyl
ieriyat
ron A-Hi
troso-di-
phenylaain Product I.
▼ on
example
2 Bensol
aulfonyl
derivative
▼ on 4 — Hitroso- 4-Hitro8O-
diphenyl- j
% based on
Rubber hydrocarbon
s fabric 2 2 2 2 asiin Time in st for the
Absorption of 2%
oxygen
non-extracted
Vulkaniaat
'extracted
Vulcanizate 11
veniger
than 8 23
29 28
29 17th
15th 17th
15th 2 30th

* Extracted as in example 10

Bas eenzolßulfonylderiTat of p ^ -KLtrosodiphenylavLn wizd by a similar procedure
prepared as in Example 2.

O CD QQ

Example 12

10 parts of 4-Ni t ro sod! Phenyl amine in 1CX) parts of acetone dissolved, and 15 parts of anhydrous sodium carbonate are admitted. The mixture is cooled to 0 ° 0 and stirred A nitrogen gas stream containing 5 parts of phosgene is slowly blown through the mixture. Stirring is stopped continued for 1/2 hour after the addition is complete. 8.8 parts of the acyl derivative are precipitated. The precipitate is collected and washed with water. After drying, it melts at 115 to 118 ° C.

Calculated for (C ₁₂ HqN ₂ O) ₂ CO: carbon 71% and hydrogen 4.3%.

found! Carbon 70.6% and hydrogen 5.9%.

Example 13

30 parts of 2,5-dimethyl-4-nitro8ophenol are dissolved in 200 parts of acetone and 25 parts of sodium carbonate are added. The mixture is stirred and ^{cooled to 0} ° C. and a solution containing 30 parts of benzotrichloride and 40 parts of acetone is added dropwise. The mixture is allowed to warm to room temperature and stirring is continued for an additional hour. 150 parts of water are added and the acyl derivative is precipitated. Ee is collected · After being washed with water and dried, it melts at 157 ° C.

Calculated for CgBgRO ₂ . CJScO <carbon 70.6%, hydrogen 5.1% and nitrogen 5t5%.

found: carbon 70.4%, hydrogen 5 * 5% and nitrogen 5 * 7%.

2 0 9 8 U 1/1 1 7 6

- Example 14

58 (Delle 4-Bfitrosodiphenylamln become 110 parts of Vaseer and 290 ropes of ethanol are added · Bann are 36 files of sodium carbonate are added, and the mixture is quickly stirred at 25 ° C. Healing benzotrichloride is added dropwise added during 30 Hin. During the addition, the mixture is cooled to prevent the temperature from exceeding 30 ° 0 rises «The beating is continued for 1 1/2 hours. Bas the precipitated benzoyl derivative is then collected and washed with a little 70% aqueous ethanol and then carefully washed with water to remove the sodium salt. The yield after drying is 82 files (93% of theory). The product melts at 134 bis

The product obtained in the form of fine orange-yellow crystals can easily be dispersed in rubber. A sample weighing 10 g decomposes at a temperature of over 143 ^° C. ₉ when the temperature is raised by 2 ^° g per minute. If this compound is obtained by benzoylation under significantly different conditions, then it has a green tinge. In addition, it cannot easily be dispersed in rubber.If it is heated in a similar way, it decomposes exothermically ^{at a temperature of 107 ° C.}

Example 15

Rubber gums are produced by the method of Example, using the antioxidants given below. Organic mixtures are ^{vulcanized for 20 min at 153 °} C., and the vulcanizates are tested in sheet form with a thickness of 0.8 mm for their antioxidant activity by determining the time in hours required for 1% oxygen to be absorbed,

209841/1 176

based on their weight, at 10O ⁰ O is required. The results given below show that the antioxidants according to the invention lose little or no antioxidant power when extracted as in Example 10.

Antioxidants nothing Product of Product of Example 5 Example 12 #, based on chewing
carbon fiber - 2 2 Tent in st for the ab
sorption of $ 1 sour
material non-extracted
Volcano! Sat 9 15th 31 extracted
Vulcanizate fewer
than 4 13th 33

Rubber geoics are made by the method of Example using the antioxidants set out below. The mixtures are 20 min vulcanized at 153 ° 0, and the vulcanizates are in shape of plates with a thickness of 0.8 mm were tested for their antioxidant activity as in Example 10. The welter below The results reported show that the antioxidants of the invention have little of their antioxidant activity lose when extracted.

20984 1/1176

Antioxidants

nothing

Lauric

acid-

rivat

from 4-Bfi

troao-

diphenyl

amine

leobuttex -n

acidic

vat of
-4-nitroeol-from

dlphenyl-
-amin

-Hexanoic acid derivative
4-

Nitrosodiphtayl
aain

n-butyric acid derivative of 4-nitrosodiphenyl- -asin

% ₉ based on caoutchouc carbon

Time in et for the absorption of 2% oxygen

unextracted 16 vulcanizate

extracted less Vulcanizate as 8

59
36

38

41 40

The acyl derivatives used above are d & diissh dafi nan 4-Hitrosodiphenylamin ait Lauryletiierid etc. Isobutyric acid chloride by the procedure of Example 6

Hexanoic acid, for example n-butyric acid, which converts ¥ ®x> f @ liPtt v <§ in Example 1.

Example 17

Rubber blends are prepared by the procedure of Example 10 using the antioxidants set forth below. The mixtures are vulcanized for 20 min at 153 ^° C., and the vulcanizates are tested for their antioxidant activity as in Example 10 in the form of 0.8 m thick plates. The results given below Dafi antioxidant according to the invention a high proportion maintained their antioxidant activity _t when extracted ·

2093 ^ 1/1178

O CO OO

Antioxidants

sucked on chew

material

Time in st for the
1% absorption
oxygen

not-extrahlertes Tulkanieat

extracted
Vulcanizate

nothing [product of the example

13th

14th

23

less «9 than 4

3-ghloro

propionyl-

derivative of

4-2Httroso-

diplienyl—

asdn

28 24

p-chloro-

bensoyl

derivative

Tone 4-hi

troso-

diphenyl

32 22

Bensoyl

derirat

from

Bensoyl

derlvat

from

4-HItTOSO-4-bltroeophenol 2-isopropyl

5-ethyl-

phesol

21
18th

13 8

product

from

example

25 30

Claims (1)

Claims 1. Stabilized rubber sets, thereby characterized as having a stabilizing force Acyl compound contain «which is an acyl derivative a Hitroso compound of the formula -O- X— K V MO (I) is »where X is a hydroxyl group or a group of the formula UHR or H (OB) B, where R is an alkyl, alkenyl, cycloalkyl or aryl group or a substituted derivative thereof, and in which the bensol ring may be further substituted can" 2. Composition according to claim 1, characterized in that X stands for a group of the formula NHB, in which R is an aryl group or a substituted derivative thereof. 3 «Composition according to claim 2, characterized in that that B is a phenyl group. 4. Composition according to claim 1, 2 or 3, characterized characterized in that the acyl group is derived from an alkane mono- or dicarboxylic acid « 5 · Composition according to claim 1, 2 or? » through this characterized in that the acyl group is from an alkamtonooarboxylic acid which contains 4 to 18 carbon atoms. 209841/1176 6 «Composition according to claim 1, 2 or 5», characterized in that the aoyl group is derived from an aryl monooder dicarboxylic acid. 7. Composition according to claim 1, 2 or 3, characterized characterized in that the acyl group is a benzoyl group 8. Composition according to one of the preceding claims, characterized in that the amount of acyl compound is 0.1 to 4.0 wt .- $, based on the rubber. 9 · Composition according to one of claims 1 to 7 »thereby characterized in that the amount of acyl compound is 0.25 to 2.0 Qev .- $, based on the rubber, is Process for the preparation of acyl compounds, at They are acyl derivatives of nitroso compounds formula X - £ 3 "-» 0 (I) where Z is a hydroxyl group or a group of Formula BHH or N (OH) H, where H is an alkyl, alkenyl, Is cycloalkyl or aryl group or a substituted derivative thereof, and wherein the benzene ring is optionally can be further substituted, characterized in that an acid chloride or an acid anhydride is used with the nitroso compound in a water-miscible solvent in the presence of an acid-binding agent 11. The method according to claim 10, characterized in that that the water-smelling solvent with water in the Ratios «between 50:50 and 90:10 is mixed. 2 0 9 8 A 1/1 176 12. The method according to claim 10 or 11, characterized in that the temperature between 10 and 40 ⁰ G
lies. 13 · Method according to claim 10, 11 or 12, characterized marked that the acid-binding agent is a weak basic metal compound 1st 209841/1 176