DE1795589A1 - Ozone protection for mixtures of rubber polymer vulcanizable by means of sulfur - Google Patents

Description

New York, NY, 10G07, USA 1795589

. fBeiegexcrvTpistr]

Ozone protection for mixtures of rubber polymer that can be vulcanized by means of sulfur ___ ____ ___

Ee is known to be produced by vulcanizing synthetic and natural rubber will crack with prolonged exposure to the weather, which will crack attributed to small amounts of ozone in the atmosphere. Accordingly, numerous different, substances effective against ozone have been proposed which are intended to counteract the harmful effects of ozone. Unfortunately discolored the majority of these mixtures under the influence of light and causes staining of the rubber, their usefulness is therefore limited to dark colored rubbers, in particular chewing cheeses containing carbon black. These mixtures, which do not discolor or become stained, but were still at risk from ozone * so the search for an effective one is essential Protective agent against ozone, which has the specified defects has not been continued.

The main patent fet the use of compounds of general. Formula,

209832/0881

_R it RtIt

RtIIl

N- (CHJ

R ¹ »'

-N (2)

R *

All ozone protective agents have been proposed for mixtures of rubber polymer vulcanizable by means of sulfur, which is normally attacked by ozone, and the protective agent according to the formula given, where R and R ^{1 are} from the group of aliphatic alkyl radicals with 1-10 carbon atoms and R ^lf and R ^m are selected from the group consisting of hydrogen and aliphatic alkyl radicals having 1-10 carbon atoms, and η has a value of 1-10.

With the present invention, a supplement or an extension of the protection according to the main patent is sought and achieved. This extension consists in that instead of the compounds according to the main patent, compounds are used as ozone protection agents which correspond to the modified formula (2), where R ¹ * ^{11 also} consists of the group consisting of hydrogen and aliphatic alkyl radicals with 1-10 carbon atoms is selected, χ has a value of 0-2, P has a value of 1-2 and the value of η for χ is greater than 0,

20983 2/088 1

the size 1-2 ,, for χ = O, the size of 1-10, and that with a value χ of 1-2, the amount of protective agent is 0.25-10 Part by weight per 100 parts by weight of rubber mixture, while for χ - 0 the rubber mixture

a) at η - 1-3 and at a sum of the carbon atoms

in B., n \ R ¹¹ and R ¹ "* ^ 5 contains between 3, 6-10 parts by weight of protective agent per 100 parts by weight of rubber mixture,

b) with η = 1-3 and with a sum of the carbon atoms in R, R ¹ , R "and R ^m of at least 5 between 0.25-10 parts by weight of protective agent per 100 parts by weight of rubber mixture,

c) with η - 4-10 and with a sum of the carbon atoms in R, R ¹ , R ¹ * and R ^tH of at least 5 between 0.25-10 parts by weight of protective agent per 100 parts by weight of rubber mixture is omitted.

The recommended compounds are in a particularly excellent way for the protection of natural and synthetic. Rubber suitable against ozone damage, under the influence of light there is little or no discoloration of the rubber; stain formation is also avoided. By means of the invent ^; All connections can be useful.

and ejnihßii ^ ch.ea rubbers ^f «chtltet v / ground by 7 0 983 2/0 881

BATH

Sulfur are vulcanizable and without protection from the Exposure to ozone. For the professional it is understood that this terminology applies to both rubber homopolymers as well as copolymers of butadiene and isoprene, such as polybutadiene rubber, polyisoprene rubber, Butadiene-styrene rubber, copolymers of isobutylene-isoprene rubber, etc. For the purpose of In the present invention, the polymers of butadiene and "isoprene" (homopolymers and copolymers) are preferred

Rubber grades. It will be understood, however, that the ozone protection agents described are effective in any known rubber. the Triamines and tetramines highlighted in the following description are of particular importance for use in Compound with styrene-butadiene rubber polymer.

The use of less protective equipment than specified, usually does not lead to a satisfactory protective effect, which indicates a chemical reaction with the components of the mixture and is also due to the high volatility. An increase in the amount of protective agent over the specified maximum values will not result in any additional improvement. With the compositions accordingly the modified formula has found it necessary

209832/0881 ;; :,

emphasized »to use between 0.25-10 parts by weight of protective agent to 1.00 parts by weight of rubber. The factors which the restrictions require, similarly dictate the compositional restrictions of the material; The availability of the material also has an influence in this regard.

When preparing the rubber grades explained, you can

the usual plasticizers, accelerators, fillers and antioxidants be added, and the resulting. Mixing as well as the deformation of the material can after any of the known methods. It is also understood that the illustrated compositions with monocrystalline or paraffin waxes or mixtures both can be conventionally used to achieve a composition which is high Has resistance to cracking under the influence of ozone.

The amines used in the practice of the invention can be obtained in a conventional manner by using a suitable alkyl dichloride, for example ethylene

209832/0881

Dichloride reacts with ammonia to produce the appropriate To produce diamine, trlamine, etc. The resulting compounds can then be used to give the desired Compounds are converted by reducing alkylation, i. H. by hydrogenation of a mixture of the Amines and a suitable ketone or aldehyde in the presence of a Raney nickel or platinum as a catalyst.

P A more detailed explanation of the invention is provided

given in connection with the following examples.

Example I.

100 parts by weight of styrene-butadiene rubber, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid and 4 parts by weight Sulfur are mixed together. To this mixture used as a control, 1 part by weight of an accelerator was added namely N-cyclohexyl-2-benzothiazolesulfonamide added.

(Samples with amines as ozone protection agents do not require an accelerator to achieve comparable vulcanization) «The The resulting mixture was vulcanized at 140.degree. Thereafter, the vulcanized mixture was in strips of 15 χ 1.3 cm cut, which were then stretched on early racks and stretched to a 20% extension. The stretched ones Strips were then one at 35 ° C (ASTM-DI 149-62T)

209832/0881

Mixture of 25 parts of ozone exposed to 100 million parts of air. The time until cracking, i.e. H. to Observation of any cracks with the naked eye was then made determined. The control piece showed within 50 hours Crack development.

For comparison purposes, the procedure described was absent the accelerator repeated while maintaining the determined concentration of the ozone protection agent; in all cases a similar vulcanization was carried out. The results are set out in Table I.

Tabel!

Ozone protection agent concentration Time to Weeks (TeUe to 100 TeUe Crack development Il Rubber) Il N / N ^ diethyl-l, 6- 1 7th Il Hexanediamine 3 32 Il 5 > 44 Il N, ^ -dimethyl-1,3- .3.5 > 51 Il Propanediamine 'δ > 51 Il N, N * -dimethyl- 3.5 > 32 Il Ethylenediamine 6th > 28 N, N »-diethyl- 3, δ > 68 Ethylenediamine 5 > 68

It was also found that the patterns that protect ozone contain agents, little or no discoloration or Showed staining before the appearance of cracks.

209832/0881

Example II

The procedure of Example I was followed with the following mixture repeated: 100 parts by weight of butadiene styrene rubber, δ parts by weight of zinc oxide, 1 part by weight of stearic acid, 4 parts by weight Sulfur, 10 parts by weight of titanium dioxide (as a whitening agent), 10 parts by weight of silicon dioxide (as a whitening agent) and 1. δ parts by weight of N-cyclohexyl-B-benzothiazole sulfonamide. The control strip cracked within 48 hours. The addition of an ozone protectant according to the invention resulted Mixtures that showed no discoloration or staining prior to cracking. The results of these experiments are compiled in Table II.

TabeUe Π

Ozone protection agent concentration time to

(Parts to 100 parts of Rissbüdung rubber)

N, N'-diethyl-1,6-hexaridiaxnine
Il
It 1
3
δ 6 days
^ ■ 97 weeks
> 34 " N, N'-dimethylethylenediamine
Il 3, δ
δ > 103 "
> 82 " N,! ^ - dimethyl-1,3-propanediamine 3, δ
δ > δ "
> δ N, N »-dimethyl-1,4-butanediamine
Il.
Il 1
3
δ 4 days
> 32 weeks
> 103 " N, N'-diethylenediamine
Il S, δ
δ > 103 "
> 103 " N, N'-diethyl-1,4-butanediamine
Il
Il 1
3
δ 1 "
> δ "
> 103 " N, N * -dipropylethylenediamine
a! o 9 8 3 2/0 8 8 1 1
3
δ 3 days
9 "
^ 60 weeks

Example ΠΙ

The procedure of Example II was repeated with the exception that instead of the styrene-butadiene rubber, 100 parts by weight of isoprene rubber was used. The control strip showed cracking, staining and discoloration within 4 days. The addition of ozone protectants according to the invention yielded mixtures which showed no discoloration or staining prior to cracking. The results of these experiments are listed in table ΠΙ.

Table m '

Ozone protection agent concentration time up to

(Parts to 100 parts of cracks - rubber)

N, N ¹ -dimethyl-1,3-propanediamine

Il

N, N »-Dimethyl-1,4-butanediamine ^J N, N ¹ -dimethyl-1,6-hexanediamine

«Il

• Nj ^ -diethyl-1,4-butanediamine

It

Il -

N, N'-Dipropylätfylenediamine 'ti

It

N, N'-dibutylethylenediamine

Il ti

It should be noted that the increase in the amounts of ozone protectants the protective effect of the styrene-butadiene mixtures according to the examples I and II increase, while lower concentrations of

3.5 24 Days Il 5 24 Il Il 1 II Il 0.25 12th ti 0.50 14th Il 1 8th Il 0, 25 19th It 0.50 14th 11 i / o 14th Il 0.25 23 It 0.50 23 ti 1 21 Il 0.25 21 It 0.50 23 1 8th

209832/0 88 1

Ozone protection agent provides optimal protection for the isoprene rubber mixture result according to Example III.

Example IV

The procedure of Example II was carried out using a Secondary tertiary amine according to Table IV repeated. It was no discoloration or staining visible before cracking.

Table IV

Ozone protection agent concentration time to

(Teüe to 100 parts cracking

Rubber) \

N, N, N'-trimethylethylenediamine 3.5 33 days

N.N.N'-trimethyl-1,3-propanediamine 3,5 > 5 weeks

¹¹ 5> 5 "

Example V

The procedure of Example III was carried out using the secondary tertiary amines listed in Table V, repeated. There was no discoloration or staining before cracking.

Table V

Ozone protection agent concentration 3.5
5 Time to
Crack formation NfN.N'-trimethyl-1,3-propanediamine
Il 3.5
6th 33 days
33 " N, N, N «-trimethylethylenediamine
It 4 weeks
4 "

209832/0881

Example VI

The procedure of Example I was repeated using a di-tertiary amine according to Table VI. Before the No discoloration or staining was discernible.

Table VI

Ozone protection agent concentration time to

[■ ' Cracking

N.N.N '^ JNP-tetramethylethylenediamine 3.5 8 days

"δ 6"

Example VII

The procedure of Example II was carried out using the method described in Table VII mentioned ditertiary amine repeated. Before cracking no discoloration and no staining was discernible.

Table VII

NjN.NSN ^ Tetramethylethylenediamine 3.5 12 days

¹¹ 6 12 ^M.

Example Vffl

The procedure of Example ΠΙ was carried out using the Ditertiary amine according to Table VIII repeated. Before the cracking, there was neither discoloration nor staining recognizable.

2098 32/088 1

Table VIII

Ozone protection agent

concentration

Time to Days Crack development Il 16 Il 30th Il 25th Il 25th 25th

N, N, N ¹ , Ni-tetramethylethylenediamine 3, 5

N, N, N ', M * -Tetraethylenediamine 1

3 ¹¹ 5

Example IX

The procedure of Example II was carried out using the Tretramin and the triamine according to Table IX repeated. There was no discoloration and none before the cracking

Staining.

Table IX

Ozone protection agent concentration Time to
Cracking 1,4, 7,10-tetramethyltriethylene
tetramine
Il
Il
Il
Il 2
3
4th
5
6th 16 weeks
16 "
16 "
32 "
16 " 1,4,7-triethyl-diethylenetriamine
Il
Il 1
S.
5 12 years
16 weeks
16 "

Example X

The procedure of Example II was repeated and ambient air ozone tests were carried out. The test pieces had a width of 1.3 cm and were wrapped around a mandrel

209832/0881

BAD ORIQ) NAL

and get a maximum stretch of 20%. The test racks were mounted outdoors and at an incline of 45 facing south. The control piece showed cracking after 10 days. The results of the test are shown in Table X.

Table X

Ozone protection agent

concentration

1, A ₁ 1, 10-tetramethyltrimethylene

tetramine ti

1,4,7-triethyl-diethylenediamine

Il Il

1 2 5

1 3 5

Time to crack

21 days 21 "28"

Il

21

7 months 7

Il

209832/0881

540

Claims (1)

Claims as ozone protection agents for rubber, where R and R ^{1 are} aliphatic alkyl radicals with 1 to 10 carbon atoms, R ", R ^'11 and R ^{1111 are} hydrogen and aliphatic alkyl radicals with 1 to 10 carbon atoms, η and χ each represent values from 1 to 2 and where the Parts by weight of the anti-ozone agent in each 100 parts by weight of rubber are 0.25 to 10. 2, mixture composed according to claim 1, characterized in that that the anti-ozone agent is a triamine, 3. Mixture according to claim 2, characterized in that the ozone protectant compound is a di-secondary tertiary amine is,, 4. Mixture composed according to claim 1, characterized in that that the ozone deprotectant compound - 2 ... ^ 09832/0881 BATH Is tetramine. 5. Mixture according to claim 4, characterized in that the Ozone protection agent prevention a di-secondary-di-tertiary amine is. 6. Use of the mixtures according to claims 1, 2, or 4, characterized in that the rubber is a Butadiene-styrene rubber is o 7ο Use of the mixture according to claims 1, 2, 3 or h, characterized in that the rubber is an isoprene rubber «, 209832/088 1 ORIGINAL ₁ NSPECTEo