DE1164669B - Process for the emulsion polymerization of 1,3-butadiene hydrocarbons - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C 08 d

German class: 39 c -25/05

Number:
File number:
Registration date:
Display day:

1 164 669
U9363IVd / 39c
October 31, 1962
March 5, 1964

It is known that in the usual emulsion polymerization of 1,3-butadiene, the percentage of the cis-oriented monomer units in the polybutadiene polymer chain strongly dependent on the polymerization temperature in the range from -20 to 80 ° C is. The data showing this known effect can be found in Synthetic Rubber, G. S. Whitby, John Wiley & Sons, New York, 1954, pp. 342 to 344, and in Me da Ii a and Freeman, JACS, 75, p. 4790 (1953). ίο

The effect of the polymerization temperature on the percentage of cis- (cis-1,4-addition) -, trans- (trans-1,4-addition) - and vinyl (1,2-addition) structure found in polybutadiene, which is produced by conventional aqueous emulsion polymerization is polymerized is given in the following table. The values in this table were obtained by analytical methods which will be described later.

Polymerization 0 '«-MC
■ 0 CIS structure % trans temperature 4th 81 ⁰ C 8th 7o vinyl 76.5 -20 15th 15th 67 + 5 18th 15.5 64 + 50 18th +80 18th

Process for the emulsion polymerization of
1,3-butadiene hydrocarbons

Applicant:

United States Rubber Company, New York, N.Y.

(V. St. A.)

Representative:

Dipl.-Ing. Dr.-Ing. R. Poschemrieder, patent attorney, Munich 8, Lucile-Grahn-Str. 38

Named as inventor:

Homer Pine Smith, Little Falls, Passaic, N.J.

(V. St. A.)

Claimed priority:

V. St. v. America January 18, 1962

(No. 167 158)

From this table it can be seen that the percentage of the cis structure of about 4% in a Polymerization temperature from -20 ° C to 18% 80 ° C increases. The proportion of the vinyl structure is almost constant, as it only goes from 15% at -20 ° C to 18% increases at 80 ° C. The percentage of transStruktur decreases as the percentage does ice and vinyl structure increases. These values essentially agree with those of Whitby, a. a. O., and from M e d a 1 i a and Freeman, a. a. Ο., Found match.

A similar effect of temperature on the structure of the diene content of copolymers of Butadiene and styrene and copolymers of butadiene with other ethylenically unsaturated monomers, which are copolymerizable with butadiene is also known (see W h i t b y, op. cit. O., B ο ν e y inter alia, High Polymers, Volume IX, Interscience Publishers, Inc., New York, 1955, and Foster et al Binder, JACS, 75, p. 2910 (1953).

It is also known to produce polybutadiene with almost 100% cis or 100% trans configuration by polymerization in an inert solvent in the presence of catalysts such as alkali metal catalysts or "Ziegler catalysts". It is also possible to prepare polybutadiene in the presence of A or Ikalimetall Alfmkatalysatoren having 80% of monomer units in a vinyl configuration. It has been found that the polybutadiene with almost 100% cis structure, which was prepared by the former process in solvent, is a polymer with low hysteresis in rubber compounds such as carcass compounds. It was further found that the polybutadiene with almost 100% trans structure is a crystalline, resinous product similar to the balata. High cis polybutadienes, which contain a small amount of trans structure, have superior freezing properties. However, the above-mentioned processes for the production of high cis content have certain disadvantages in that they require a monomer of extraordinary purity, solvents of similarly high purity, and catalysts prepared in the absence of air and / or water. In addition, measures must be taken before and during the reaction in these processes to remove and exclude air and water from the apparatus used and from the reaction zone, since otherwise the reaction is interrupted or progresses slowly. Furthermore, the polymer obtained in fairly dilute solution is at

409 537/596

3 4

Termination of the reaction by catalyst residues The additives used according to the invention have

contaminated, making difficult and expensive removal the property, the portion of the cis structure in the polynung both the solvent and the catalysis butadiene and in the diene portion of the molecular chain of Sator residues from the polymer obtained copolymers of 1,3-butadiene with styrene, the before it is in usable form. 5 are produced by emulsion polymerization, It would be very beneficial if using polybutadiene to increase above that which is normally in a relatively high cis content and thus good these polymers are included when they are after Low temperature properties and low hysteresis same technique at the same temperature without This additive can be produced by the usual emulsion polymerization. The invention could be, d. H. by a method, the io measure to be used affects the amount of additive does not have the disadvantages described above. Vinyl structure is not essential, so the increase in

It is well known that the quality of the cis structure is a corresponding decrease in the trans emulsion polymers of butadiene and mixed structure results.

polymers of butadiene with such co-mono- The maximum percentage of cis structure, the

mers, such as styrene and acrylonitrile, can be improved with the additives to be used according to the invention by being obtainable at low temperatures, ie, is almost independent of the polymerization temperatures in the range from 0 to 10 ° C., polymerization temperature and has in the range from 0 to s is set. This "cold rubber," the at about 8O ⁰ C ranging from 17 and 20 ° / _0th It should be noted that 5 "C is produced is more suitable for tire treads that the effect of the additives according to the invention in than a similar rubber that is produced at 50 ° C Branching at borrowed to the effect of the temperature alone is attributed to the low temperatures. It is also structure, as described above, occurs. For this simpler, a polymer with a high molecular basis, the additives according to the invention produce at weight or a copolymer that is free of gel temperatures above 8O ⁰ C is no appreciable increase, by polymerizing at these low temperature 25 of the cis-structure compared with that to be obtained by the doors. in addition, the process temperature alone, at about 8O ⁰ C polymers having Niedrigtemperaturpolymerisate better than that with a cis structure of more than 20 ° / o. It is therefore produced at 50 ° C. However, as with the usual can be chen no upper limit for the temperature present, emulsion polymerization applies vei the cis content of at which these additives, the polymerization temperature is dependent as described above 30, however, effect the additives at temperatures above that contain "cold rubbers" less 8O ⁰ C no Significant increase in the cis structure cis structure than those produced at high temperature compared to those usually occurring, and therefore have the disadvantage of low ice The additives used according to the invention are in

Structure, d. H. poor resistance to cold. It is very effective in small amounts. The solubility and It would be very advantageous to have such cold rubbers with the effectiveness of the cobalt salts at a given poly to produce higher cis content than in the merization conditions of various cobalt products the usual emulsion polymerization for salts. In general, inventions are lower Temperatures is found. This chewing will get the best results, though chuke would take advantage of less branching, 0.5 to 50, preferably 2 to 25 millimoles of higher molecular weight cobalt, and better processing 40 salt per 100 parts by weight of butadiene as they have the "cold rubbers" and they will.

Advantages of better low-temperature characters- The additives are only available during the polymerization

characteristics and low hysteresis as they are highly effective. Treatment of a finished latex entcis content are connected. neither in the presence or absence of free

There has now been a process for aqueous emulsification with the addition of no increased radicals sion polymerization of butadiene or its micro-structure.

Mixtures with styrene found in the polymer. The additives are obtained in the presence of various emulsifiers are that in the molecular chain 17 to 20% gators, initiator systems, salts and other ingredients-oriented Monomer units .containing, and part of the usual emulsion polymerization reaction Effective almost independently of the 5 ° polymerization mixtures.

temperature in the range from 0 to 50 ° C. Among those to be used according to the invention

In the process for emulsion polymerization of cobalt salts, the preferred diketones are the 1,3-butadiene hydrocarbons and their Mischun- jenigen in which R and R 'lower alkyl radicals with gene with styrene in an aqueous medium in the presence of 1 to 4 carbon atoms or phenyl, lower usual emulsifiers and polymerization catalysts 55 phenalkyl or alkylphenyl radicals with 6 to 10 carbonators is characterized in that one is in to- substance atoms. These are because of the lower additional presence of divalent cobalt salts of molecular weight, and because they are more readily available of /? - diketones of the formula are preferred. Acetylacetone is a special one

added diketone; Examples of other preferred 60 diketones are l-phenyl-l, 3-butanedione, 1,3-diphenyl-

R - C - CH ₂ - C - R '1,3-propanedione. The cobalto salts of each of these ver

bindings act as a structure-controlling additive.

O O The formulations to be used according to the invention

contain, as already stated, customary emulsifiers, 65 catalysts and, if appropriate, regulators, such as

in which R and R 'are saturated aliphatic, aromatic, they are derived from B ο ν e y and others. are described. The quantities alkaryl or aralkyl hydrocarbon radicals, ratios of these ingredients as well as the amount polymerized. of water and existing polymerizable mono-

20th

mers can just as well, as for example from B ο ν e y i.a. described, be.

The cobalt salts of / J-diketones can be made by mixing solutions of the diketone and cobalt acetate in water or alcohol and the pn value is brought to almost neutral or by turning the alcoholic mixture into a strong one Solution of sodium acetate is poured. These methods are known and described in the literature (See Inorganic Synthesis, W. C. Fernelius, Editor, McGraw Hill, New York, 1946, Vol. II, Chapter II). ,

The polymerization method used in the following examples is the usual emulsion polymerization. A test bottle is filled with distilled or deionized water, emulsifier, structure-controlling additive (if used), salt and / or buffer solution, styrene (if used) and modifier. After filling, the bottle is flushed with nitrogen. Then the substances that make up the redox polymerization catalyst system are added. The bottle is cooled, filled with butadiene and then sealed. An initiator is added through the cap and the polymerization is carried out with head-over-shaking in a water bath at a suitably controlled temperature. The course of the reaction is followed by determining the solid constituents in the usual way. At the end of the reaction, the sample is interrupted with hydroquinone or another suitable substance and the bottle is then vented. A suitable antioxidant is added and then the latex is coagulated with salt and acetic acid to give fine crumbs. The remaining additive is removed by dipping the crumbs in acetic acid or methanol, or both in sequence. The excess additive can, for. B. removed by extraction of the latex with solvent prior to coagulation. After removing the additive, the crumbs are dried in the usual way. The dried polymer is then subjected to the usual tests in order to determine the polymer qualities, such as gel content and viscosity in dilute solution. Tests are also performed to determine the structure of the polymer. The structure of the polymer is determined by infrared absorption of a carbon disulfide solution of the purified polymer, with the exception of the case of insoluble polymers. The polymer dissolved in carbon disulfide is purified by three successive precipitations with methanol, followed by redissolving in carbon disulfide. After the third precipitation and redissolution, contaminating methanol is pumped off and the pure solution is filtered through filter paper or a silk screen. The concentration of the carbon disulfide solution is adjusted to a suitable value, approximately 20 g / l, and the structure of the polymer sample is determined in the usual manner by infrared spectroscopy, with observations for the trans on the 937 cm ^-1 band, for the Vinyl on the 911 cm ^-1 tape and for the cis structure in the range of 723 cm ^-1 . This procedure is given in the article by Hampton in Analytical Chemistry, Vol. 21, 1.8. 1959, p. 923. The percentage values of the structure are normalized, ie multiplied by 100 over the total percentage of the three structure types found, so that the set percentage resulted in a total of 100. With all experiments in which additives are used, parallel tests are carried out in which no structure-controlling additive is used.

In the case of insoluble polymers, the polymer is purified by solvent extraction, ground to very small particles and then tabletted with finely powdered potassium bromide, and the infrared measurements be familiar with these

ίο tablets carried out (see e.g. H. H a u s d ο r f, applied Spectroscopy, 8, p. 131 [1954]).

The following examples illustrate the invention. All parts and percentages given relate to based on weight, unless otherwise specified.

example 1

45 This example shows the effect of the additive concentration on the polybutadiene structure.

Five samples of polybutadiene are made in the manner indicated above 1A to IE manufactured. A different amount of cobalt acetylacetonate is used for each sample used: IA: none; IB: 0.01 part; IC: 0.1 part; ID: 1.0 part; IE: 10 parts. The other components are the same for each sample, as follows:

Parts distilled water 200

Potassium oleate 5

Potassium carbonate, anhydrous .. 0.5

A mixture of tertiary mercaptans, approximately 60% tertiary dodecyl mercaptan, 20% tertiary tetradecyl mercaptan
and 20% tert-hexadecyl mercaptan (Tr ο ya η et al., Rubber World, Vol. 121, p. 68) 0.39

Sodium formaldehyde sulfoxylate 0.2

Trisodium salt of ethylenediaminetetraacetic acid 0.042

FeSO ₄ -7 H ₂ O 0.028

Distilled water 9.73

Butadiene 100

Diisopropylbenzene hydroperoxide 0.3

as

aqueous

Solutions!

55 Immediately after adding diisopropylbenzene hydroperoxide, all sample bottles are placed in a polymerisation bath rotated by 5 ° C. At appropriate times, the samples are removed from the bath removed and treated with 0.1 part hydroquinone as an interrupter. It is found that the Cobaltoacetylacetonate in IE did not completely dissolve. All samples are then treated with 1 part antioxidant (Ν, Ν'-di-ß-naphthyl-p-phenylenediamine), add treated as a 50% paste. All samples are made with an aqueous solution of NaCl and Acetic acid coagulated and washed with water. Samples 1D and 1E are additionally diluted in aqueous acetic acid and then soaked in methanol for further purification. After drying parts of the samples are further purified as described above for the infrared determination of the structure as carbon disulfide solutions of polybutadiene

65

is. The results are given in the table below.

Polybutadiene made at 5 ° C

P _rn Kf, Parts cobalto- ice cream Structure, trans ΓΙ UUC acetylacetonate 7th vinyl 79 IA 0 8th 14th 77 IB 0.01 11 15th 73 IC 0.1 20th 16 63 ID 1.0 21 17th 62 IE 10.0 17th

acts. The samples are coagulated with a hydrochloric acid solution and the fine crumbs are washed with water. The samples 2 B and 2 C are with dilute aqueous acetic acid and then with Treated methanol for further purification. After washing with methanol, all three samples are removed dried in a vacuum oven. The samples are weighed and the percentage conversion of the monomer to the polymer is calculated for each sample. The samples are used for structural analysis purified by infrared as indicated above. The results are compiled in the following table.

Polybutadiene, produced at 5 ^° C

15th

From this table it can be seen that all samples 1 B to 1E a lower percentage of the trans structure and a higher percentage of the cis structure as Control Sample 1A which did not contain cobalt acetylacetonate. It is from it too see that as the cobalt acetylacetonate content increases, the percentage of cis and trans structure in the polybutadienes formed asymptotically approaches a number of limit values and that amounts of the cobaltoacetylacetonate of more than 1 part for the specified formulation only has a slight effect in with respect to the change in the structure of the polybutadiene formed.

B e i s ρ i e 1 2 3 «

This example shows the effect of the additive on the polybutadiene structure as a function of the percentage of the monomers converted to the polymer.

Three polybutadiene samples 2 A to 2 C are prepared in the manner indicated above. Sample 2 contains A. no cobalto salt; Samples 2 B and 2 C each contain 1 part of cobalt acetylacetonate. The other components are the same in each sample, as follows:

Parts

Distilled water 200

Potassium oleate 5

Potassium carbonate, anhydrous 0.3

Potassium hydroxide 0.12

Mixture of about 60% tert-dodecyl mercaptan, 20% tert-tetradecyl mercaptan and 20% tert-hexadecyl mercaptan 0.47

Sodium formaldehyde sulfoxylate 0.2

Trisodium salt of ethylenediaminetetraacetic acid 0.042

FeSO ₄ · 7 H ₂ O 0.028

Distilled water 9.73

Butadiene 100

Diisopropylbenzene hydroperoxide 0.3

Immediately after the addition of the diisopropylbenzene hydroperoxide, the bottles are filled with the samples rotated in a polymerization bath at 5 ° C.

At the times indicated in the table below, the polymerizations are 0.1 part Hydroquinone interrupted and the bottles vented. The samples are then mixed with 1 part N, N'-di- / 3-naphthyl-p-phenylenediamine used as an antioxidant

sample Parts
Cobalto
acetyl Reak
tion time ¹ Vo at
change
the mono ice cream Structure, / 0 acetone hours meren 8th trans 2A 0 16 49 18th 76 2 B 1 5 13th 17th 63 2C 1 53 57 64 vinyl 16 19th 19th

From the table it can be seen that the effect of the cobaltoacetylacetonate on the structure of the produced Polybutadiene does not depend on the percentage of the monomer converted to the polymer, since 2 B and 2 C show similar structural analyzes, although the percent conversion of monomers to polymer is quite different, namely 13% for sample 2 B and 57% for sample 2 C.

Example 3

This example shows the effect of the additive on the polybutadiene structure at different polymerization temperatures .

Sixteen polybutadiene samples 3 A to 3 P are prepared as indicated above. These will be in two Groups shared, namely Group 3 A to 3 G, which are made without cobalto salt, and Group 3 H to 3 P, in which each sample corresponds to a sample in Group 3 A to 3 G, but cobaltoacetylacetonate in the Contains the amounts given in the following table. Each group contains three subgroups in which the polymerization is carried out at 5 or 50 and 80 ° C. All appropriate samples will be polymerized at the same temperature. This arrangement enables easy comparison of the effects the polymerization temperature on the structure of the polybutadiene, both with and without additives. For clarification, the average structural analysis of each subgroup is given.

Samples 3 A to 3 C and 3 H to 3 K, polymerized at 5 ° C., are identical to sample IA with Exception that the samples contain 3 H to 3 K cobalt acetylacetonate in the specified amounts.

Sample 3 D, polymerized at 5 ^° C., is identical to sample 1A, with the exception that 0.5 part of K ₂ CO _{3 is} replaced by 0.3 part of K ₂ CO ₃ and 0.12 part of KOH to increase the rate to reduce. Samples 3 L to 3 M, polymerized at 5 ⁰ C, the sample correspond to 3 D, except that they contain Cobaltoacetylacetonat in the specified amounts.

Samples 3 and E 3 F and the corresponding samples 3 and 30 N, all of which are polymerized at 5O ⁰ C, containing the following ingredients:

3E 3F 3 N Parts 200 200 3O 5 5 Distilled water 200 0.39 200 Ethylene oxide
Propylene oxide
Soot-
Mixed polymer 5 - 0.4 5 Controller mix like
in example 1 1 1 0.39 tert-octyl mercaptan 0.4 100 100 - Azobisisobutyro
nitrile 1 3 1 Butadiene 100 100 Cobaltoacetyl
acetone 2

sample

¹ TOiIe ßobaltoacetylacetonate

ice cream

Structure, ° / ₀
Vinyl I.

trans

Polymerization temperature ^{80 0 C}
3Gl 0 I 18 I 18

Polybutadienes,
made with cobalt acetylacetonate

Polymerization temperature 5 ° C

Sample 3 G and its corresponding sample 3 P are both polymerized at 80 ° C and contained the following components:

3H pole 1.0 31 10.0 3Y average 6.67 3K 6.67 3L 1.0 3M 1.0 ymerisatic
3.0 2.0 average 3N 30th

20th 17th 21 17th 19th 18th 20th 20th 18th 19th 17th 19th 19.2 18.3

17th 19th 17th 19th 17th 19th

Distilled water

Emulsifier alkylaryl sodium sulfonate

Regulator mixture as in example 1

K ₂ CO ₃

Azobisisobutyronitrile

Butadiene

Cobalt acetylacetonate

3G

3P

3P

Polymerization temperature 8O ⁰ C
3.0 I 20 I 18

63
62
63
60
63
64
62.5

Parts

200

5 0.47 0.3 1.0 100

200

0.47 0.3 1.0 100 3

All sixteen samples are polymerized, cleaned, and analyzed in the manner outlined above with the exception that infrared spectral analysis for structure 3 G and 3 P with solid tablets of with potassium bromide mixed polymer is carried out, in the known manner. The The results are compiled in the following table.

Polybutadienes made at different temperatures

sample Share Cobalto ice cream Structure, ° / 7th 14th 15th 18th trans acetylacetonate vinyl 8th 15th 15th 18th Polybutadiene controls 9 17th 15th 18th Polymerization temperature 5 ° C 8th 16 79 3A 0 8th 15.5 77 3B 0 Polymerization temperature 5O ⁰ C 74 3C 0 0 76 3D 0 0 76.5 average average 67 3E 67 3F 67

From the examination of the averages of the structural analysis of the PoIybutadiene prepared without Cobaltosalz is apparent that the percentage content of cis-structure changes from 8% at 5 ° C to 15% at 50 ⁰ C and 18% at 8O ⁰ C, and that the percentage of decreases the trans-structure of 76.5% at 5 ° C to 67.0% at 5O ⁰ C and 64% at 8O ⁰ C. Vinyl analysis changes little with temperature. These results are in good agreement with the known changes discussed above.

In the case of the polybutadienes produced in the presence of cobalt acetylacetonate, however, the percentage is both the cis and the trans structure are essentially constant with temperature. the Constancy of the percentage of vinyl structure of polybutadienes made with cobaltoacetylacetonate is similar to that of the polybutadiene control samples.

It is seen that in the presence of Cobaltoacetylacetonat prepared polybutadiene a substantially non-varying amount of cis, vinyl and trans structure in the temperature range of 5 to 8O ⁰ C, and in that in this temperature range, the percentage content of the monomer units of in the presence of Cobaltoacetylacetonate produced polybutadienes with cis configuration is 17 to 20%. By comparing Samples 3H and 31, it can be seen that the use of more than 1 part of cobaltoacetylacetonate in the formulation results in little or no additional change in structure.

Example 4

This example shows the effect of cobalt salt of various /? - diketones on the structure of the polybutadiene.

Eight samples 4A to 4H were made in the above-mentioned manner. Samples 4 A to 4 D are

identical to sample 1A, except that the 0.5 parts of K ₂ CO _{3 have been} replaced with 0.3 parts of K ₂ CO ₃ and 0.12 parts of KOH (identical to sample 3D), and with the exception that they are the in the following

409 537/596

Table included addendum. Samples 4 E, 4 F would assume that they have the addition given below

and 4 H are identical to Sample 1A, with the exception that they _{contain 0.12 parts of KOH in addition to 0.5 parts of K 2} CO ₃ , and the further exception that they contain the additive indicated in the following table. Sample 4G is identical to Sample IA, with which Aushalts.

The samples were ^{polymerized at 5 °} C., cleaned and analyzed in the manner indicated above. The results are compiled in the following table.

additive None MoI used ° o ice "'"Vinyl ⁰ Z ₀ trans sample None per 100 parts 9 16 75 None Butadiene 8th 16 76 4A Bis- (1,3-diphenyl-1,3-propanediono) cobalt 9 16 75 4B Bis (1-phenyl-1,3-butanediono) cobalt 13th 18th 69 4C Sodium cobalt acetylacetonate -. 18.5 18.5 63 4D Cobalt acetylacetonate 0.008 18th 19th 63 4E Cobalt acetylacetonate 0.0017 18th 18th 64 4F 0.0117 10 17th 73 4G 0.0117 4H 0.0117

It should be noted that the control samples 4A, 4 B and 4 C ^un a cis structure of 9 or 8 or 9% of a trans-structure of 75 and 76 and 75% show, in good agreement with each other and with the previous control samples. The additions of bis ~ (1-phenyl, 3-butanediono) cobalt in Sample 4E and sodium cobaltoacetylacetonate in Sample 4F both increase the percentage of cis structure and decrease the percentage of trans structure to about the same extent as cobaltoacetylacetonate in Sample 4G. The bis (1,3-diphenyl-1,3-propanediono) cobalt in Sample 4 D is about half as effective as the cobaltoacetylacetonate in Sample 4G even in a greatly reduced amount. On the other hand, the cobaltoacetylacetonate in Sample 4H shows little or no tendency to increase the cis structure.

This example shows four cobalto salts of / 3-diketones, namely cobaltoacetylacetonate, sodium cobaltoacetylacetonate, bis (1-phenyl-1, 3-butanediono) cobalt and bis (l, 3-diphenyl-l, 3-propanediono) cobalt, which are used to increase the percentage of the cis structure and lowering the percentage of the trans structure of those made in their presence Polybutadienes are effective.

Example 5

This example shows a comparison of vulcanized rubber containing at 5 ° C in the presence of Cobaltoacetylacetonat prepared polybutadiene, with a vulcanized rubber containing polybutadiene produced at 5 ° C without Cobaltosalz, and without having a vulcanized rubber at 50 ⁰ C Contains polybutadiene made from cobalto salt.

Three samples of polybutadiene 5 A, 5 B and 5 C are prepared in the manner indicated above. The following Recipes are used.

5A

5B

5C

Cobalt acetylacetonate

Distilled water

Potassium oleate

Potassium carbonate

Potassium persulfate

Regulator mixture as in Example 1. Dodecyl mercaptan

200
4.5 *
0.5

0.56

200
5
0.5

0.37

200 5

0.5 0.5

0.76

(Flushing with nitrogen)

Sodium formaldehyde sulfoxylate

Trisodium salt of ethylenediaminetetraacetic acid

FeSO _{4 7H 2} O

Distilled water

Butadiene

(Closing)

Diisopropylbenzene hydroperoxide

Polymerisation:

Temperature, ⁰ C

Time, hours

Interruption

0.2 0.2 0.042 0.042 0.028 0.028 9.73 9.73 100 100

0.3

43
Hydroquinone

0.3

5
7th
Hydroquinone

Methanol **
76

hydrochloric acid
66

Antioxidant ***

Coagulation

Conversion of the monomer to polymer,% · · ·

* After 16 hours Za ¹ additional 2.5 parts of potassium oleate (as a 10 ° / ₀ solution) are added. ** Also soaked in acetic acid, soaked in methanol and washed with methanol. * * * NjisT-Di-zS-naphthyl-p-phenylenediamine.

100

50 22

Potassium dimethyldithiocarbamate

Hydrochloric acid 73

The obtained polybutadienes were examined and the following results were obtained.

IO

Gel content,%

Viscosity in dilute

solution

ML-4-100 ° C

Ratio of vinyl to trans

(by infrared analysis) ..

Then the three rubber mixtures 5 D, 5 E and 5 F are produced, the polybutadiene of the samples 5 A or 5 B and 5 C, mixed with carbon black as follows:

5A

2.21 51

0.28

5B

2.07 49

0.22

SC

2.35 52

0.27

Polybutadiene

from sample 5 A ....

from sample 5 B ....

from sample 5 C ....

soot

Zinc oxide

asphalt

Stearic acid

Mercaptobenzothiazole
Diphenylguanidine ..
sulfur

5D 5E 95 - 100 50 50 5 5 5 5 6.5 1.5 1.5 1.5 0.4 0.4 2 2 165.4 165.4

Portions of these mixtures are in a 2.54 mm mold at 144.4 ° C for 30, 45 and 60 minutes vulcanized, and a portion of each of these masses is 45 minutes at 144.4 ° C in a 12.7 mm die vulcanized. Various tests are performed on the vulcanized samples, and there will be achieved the following results:

30th

5D I 5E I 5F

Vulcanization time in minutes at 144.4 ° C
I 60 I 30 45 I 60 I 30 45

Tensile strength, kg / cm ² ...

Strain, %

Durometer A

(ASTM-D 676)

Modulus at 200%, kg / cm ²
Modulus at 300%, kg / cm ²

Torsional hysteresis at
Room temperature ....

Torsional hysteresis at
140 ° C

Rebound,%
(ASTM-D 1054)

* 10% recovery at
* 30% recovery at
* 50% recovery at
* 70% recovery at

processing

* At 150% elongation.

⁰ C.
⁰ C.
⁰ C.
³ C.

133.57 600

47.6

88.2

0.351 0.187

-70.6 -63.2 -54.3 -44.4

124.25 540

65

53.2

98.7

0.330 0.195

47

-68.7 -64.0 -55.3 -46.2

113.05 510

53.9 101.5

0.346 0.200

-67.4 -63.9 -55.8 -46.2

best of 161.00
690

60

37.45
72.1

0.314
0.191

-50.7
-32
-23.2
-16.2

157.5
650

62

43.75
84

0.317
0.183

51

-57.2
-35.8
-25.6
-19.4

mediocre

112.7 125.65 560 540 62 59 44.1 48.3 85.75 91 0.319 0.325 0.189 0.172 -56.6 -69.8 -36.5 -62.7 -26.9 -51.3 -10.0 -40.0 G on s

129.85 560

60

50.4

92.75

0.325 0.181

47 -70.2

63.4 -53.2 -42.5

128.8 550

-68.4 -64.0 -54.4 -43.0

It can be seen that the tensile strength, elongation, and modulus values for Sample 5 D, which is rubber containing polybutadiene made at 5 ° C in the presence of cobaltoacetylacetonate, are the values for Sample 5 F, which is rubber containing polybutadiene that is prepared at 50 ° C without Cobaltosalz, similar as are the values of the sample 5 e, the rubber containing polybutadiene, which is prepared at 5 ⁰ C without Cobaltosalz. There is a striking similarity between the cold resistance values of samples 5 D and 5 F, since the recovery temperatures coincide ^{within 2 or 3 ° C.} On the other hand, Sample 5 E, which has a lower percentage of cis structure than 5 D or 5 F, tends to crystallize and therefore has much higher recovery temperatures. This example therefore shows that a rubber composition containing a polybutadiene, which is prepared in the presence of Cobaltoacetylacetonat at 5 ⁰ C, namely, Sample 5 D, a better low temperature resistance than a rubber containing a polybutadiene at the same temperature, 5 ° C, is made without cobalto salt, namely sample 5 E.

Example 6

This example shows the effect of cobalt acetylacetonate on the structure of a copolymer from butadiene and styrene (75% butadiene, 25% styrene).

As described above, three samples 6 A, 6 B and 6 C of a copolymer of butadiene and Made of styrene. Sample 6 A is a copolymer that is produced at 5 ° C in the presence of 1 part of cobaltoacetyl

acetonate is produced. Sample 6 B is a similar copolymer, which is made at the same temperature, 5 ⁰ C without Cobaltosalz. Sample 6 C

is a similar copolymer, which is prepared without Cobaltosalz at 50 ⁰ C. The following recipes are used:

6A

6B

6C

Cobalt acetylacetonate

Distilled water

Potassium oleate

Potassium carbonate

Potassium hydroxide

Potassium persulfate

Regulator mixture as in example 1

Dodecyl mercaptan

Styrene

(Flush with nitrogen)

Sodium formaldehyde sulfoxylate

Trisodium salt of ethylenediaminetetraacetic acid ....

FeSO ₄ · _{7H 2} O

Distilled water (cooling with ice)

Butadiene

(Closing)

Diisopropylbenzene hydroperoxide

Polymerisation:

Temperature, ° C

Time, hours: minutes

Breaker (for all)

Antioxidant ***

Coagulation

Conversion of butadiene to polymer,%

187.5 *
4.5 *
0.5

0.56

25th

0.20
0.042
0.028
9.73
75

0.3

5
32:20

200
5

0.3
0.12

0.37
25th

0.20
0.042
0.028
9.73
75

0.3

5
14:38

200 5 0.5

0.5

0.47 25

75

50 14:25

0.625 parts potassium dimethyldithiocarbamate

Methanol **
56.6

Methanol
55

Methanol 72.5

* At 20% conversion, an additional 2.5 parts of potassium oleate in 22.5 parts of water are added. ** Polymer is soaked in 10 percent by volume acetic acid, then in methanol. * * * N, N'-di- | 8-naphthyl-p-phenylenediamine.

Three to six vessels of each sample preparation are polymerized and mixed at the same time. With Various tests are carried out on the products thus obtained, the results of these tests gave the following properties.

Gel content, ^_0/0

Viscosity in dilute

solution

Ml -4-100 ° C

trans structure,%

Vinyl structure,%

cis structure,%

Total ° / ₀

6A 6B 0 0 3.05 2.45 110 55 65.3 76.7 15.9 15.1 18.8 8.2 100 100

6C

1.96 47
68.6
15.7
15.7

100

* The percentage of structure is based on the butadiene content only indicated, so that a comparison with homopolymers can be carried out more easily.

From these results it can be seen that cobaltoacetylacetonate is responsible for changing the structure of the Butadiene in a copolymer of butadiene and styrene as well as in a homopolymer of Butadiene is effective.

Example 7

This example shows a comparison of a vulcanized rubber which contains a butadiene-styrene copolymer produced in the presence of cobaltoacetylacetonate at 5 ° C., with a vulcanized rubber which contains a butadiene-styrene copolymer produced at 5 ° C. without a cobalto salt, and with a vulcanized rubber containing a manufactured at 5O ⁰ C without Cobaltosalz butadiene-styrene copolymer.

Three rubber compounds 7 A, 7 B and 7 C are produced. Samples 7 A, 7 B and 7 C contain the Butadiene-styrene copolymers from samples 6A or 6B or 6C mixed with carbon black as follows:

7A

7B

7C

Copolymer from sample 6A from sample 6B from sample 6C

soot

Zinc oxide

asphalt

Stearic acid

Mercaptobenzothiazole

Diphenylguanidine ..

sulfur

100

50 5 5

6.5 1.5 0.4 2

100

- · 100 50 50 5 5 5 5 6.5 6.5 1.5 1.5 0.4 0.4 2 2

Portions of these masses are vulcanized at 144.4 ° C. for 30, 45 and 60 minutes. Vulcanized with these Samples are run through various tests and the following results are obtained:

30th 7A 7B 30th 45 60 30th 7C 60 66 65 66 67 62 68 205.10 254.10 249.90 2 68.80 221.90 45 218.40 Durometer A 430 Vulcanization time in minutes at 144.0 ° C 600 530 540 560 64 500 Tensile strength, kg / cm ² ... 59.50 45 ι 60 41.30 48.65 39.90 43.05 198.70 39.20 strain 104.30 68 68 73.50 87.50 70.70 78.05 470 73.50 Modulus at 200%, kg / cm ² 211.40 183.40 48.30 Modulus at 300%, kg / cm ² 0.31 380 j 350 0.35 0.33 0.34 0.35 90.30 0.33 Torsional hysteresis at 68.25 69.30 Room temperature ... 0.15 127.40 130.20
I. 0.17 0.16 0.16 0.15 0.33 0.15 Torsional hysteresis at I. VJ J. I 46 14O ⁰ C 0.30 j 0.30 0.15 Rebound,% I. 41 Recovery temperature 0.12 0.13 test (measured -53.1 i
46 - -48.6 -48.4 -47.8 -51.0 -49.6 at 150%) -47.5 j -42.9 -42.9 -42.1 -44.9 -44.2 10% recovery at ° C -42.1 -37.4 -37.7 -36.6 -40.0 -50.5 -38.4 30% recovery at ⁰ C -34.5 j -30.2 -30.3 -29.3 -31.7 -44.7 -31.3 50% recovery at ⁰ C At the -51.8 -51.7 preferably at the -38.7 next best 70% recovery at ⁰ C -46.6! -46.4 -31.2 processing -41.3 | -41.1 -33.8 i-33.5 schier.htesten (Mooney too high)

Although the rubber of Sample 7 A has an excessive Mooney viscosity value (as can be seen from the processing properties, the stiffening modulus at 300% and the short stretch in Sample 7 A), it is in the cold resistance of both Sample 7 B (rubber, the the copolymer prepared without Cobaltosalz at 5 ⁰ C contains) as superior to the sample 7 C (rubber containing the copolymer prepared at 50 ⁰ C without Cobaltosalz). The improvement of the cold resistance of Sample 7 Sample 7 A over B is approximately 2.2 to 2.75 ° C and over Sample 7C about 1,1O ⁰ C.

Claims (2)

Patent claims: 1. Process for the emulsion polymerization of 1,3-butadiene hydrocarbons or mixtures thereof with styrene in an aqueous medium in the presence of customary emulsifiers and polymerization catalysts, characterized in that that in the additional presence of divalent cobalt salts of / 9-diketones of the formula R. ρ / " ¹ XJ c R ' 409 537/596 19 20 in which R and R 'are saturated aliphatic, aromatic, cobalt salts of the / S-diketones per 100 parts by weight of alkaryl or aralkyl hydrocarbon radicals which carry out monomers,
polymerized. 3. The method according to claim 1 and 2, characterized 2. The method of claim 1, marked characterized in that to draw in the polymerization that the polymerization is performed in counter-5 temperatures in the range of 0 to 50 ⁰ C by waiting from 0.5 to 50 millimoles of divalent. 409 537/596 2.64 © Bundesdruckerei Berlin