DE1106961B - Process for the production of hydrogenated butadiene polymers - Google Patents

Description

GERMAN

The present invention relates to hydrogenated, linear butadiene polymers.

The compounds of the present invention are prepared by hydrogenation of butadiene polymers, in which at least 90% of the polymer is formed by 1,4-addition of the monomer. These Polymers have a predominantly linear structure, with vinyl unsaturation not exceeding 10%. The polymers produced according to the invention differ considerably from polymers which are produced by Emulsion polymerization can be obtained because emulsion polymers have a larger proportion of 1,2-addition products contain.

The new compounds are essentially colorless, clear, and can be easily extruded will.

The unsaturation of the polymer is reduced by hydrogenation until the material exhibits residual unsaturation less than 30% of the original Has unsaturation. The products are not subject to stress reduction, have good flexibility, low ash, low flow rate, good tensile strength, high crystalline flex point and retain their flexibility at low temperatures.

Synthetic rubber made by emulsion polymerization has been hydrogenated and plastic products have been obtained by this process. These substances have many beneficial properties for various uses; they differ significantly from the products of the present invention. Rubbery polybutadiene produced by emulsion polymerization generally has 20 or more percent vinyl unsaturation, while the polymers used as starting materials of the present invention have 10 or less percent vinyl unsaturation. The hydrogenated emulsion polymers can be extruded; but the process is quite difficult and the compact has a rough surface, while the products of the present invention can easily be pressed into a smooth-surfaced material. The hydrogenated emulsion polymers are amorphous and therefore do not have a crystalline freezing point. They generally become rubbery when heated and eventually become soft and very viscous. They are often dark, gray to black, colored unless they have undergone special treatment, e.g. B. the acid treatment of U.S. Patent 2,893,982. The hydrogenated polymers of the present invention are crystalline and have a crystalline freezing point above 65 ° C. They also have a low flow rate or melt viscosity. Films and thin sheets are transparent and colorless or at most only very weakly colored. They have a much narrower molecular weight distribution than emulsion methods of manufacture
of hydrogenated butadiene polymers

Applicant:

Phillips Petroleum Company,
Bartlesville, OkIa. (V. St. A.)

Representative: Dr. F. Zumstein,

Dipl.-Chem. Dr. rer. nat. E. Assmann

and Dipl.-Chem. Dr. R. Koenigsberger, patent attorneys,

Munich 2, Bräuhausstr. 4th

Claimed priority:
V. St. v. America December 4th 1958

William Bryan Reynolds, Exelsior, Minn. (V. St. Α.), has been named as the inventor

polymers. You can also do much faster than emulsion polymers be hydrogenated.

The polymers used as starting materials for the present invention are prepared in a known manner in the presence of various organometallic or metal hydride catalyst systems. As mentioned above, they are predominantly linear and have not more than 10 ° / ₀ vinyl unsaturation.

The polymers used as the starting material of the present invention are homopolymers of Butadiene and copolymers of butadiene and styrene, with no more than 30 parts by weight of styrene per 100 parts by weight of total monomers are used. The polymerization can be effected in the presence of any of the aforementioned catalyst systems.

By suitable choice of the catalyst and the process conditions in the preparation of the polybutadiene can obtain hydrogenated products with a density of about 0.90 up to 0.93 or higher at 20 ° C will.

The hydrogenation is carried out in the presence of a solution. means, such as cyclohexane, methylcyclohexane, decahydronaphthalene, Benzene, toluene, dioxane, isooctanes, isoheptanes, n-heptane, tetrahydronaphthalene or mixtures this solvent. When aromatic solvents are used, they generally will hydrogenated simultaneously with the polymer.

109 607/444

3 4

The hydrogenation can be discontinuous or continuous. Turning of emulsion polymers is necessary. need to be carried out. When sufficiently hydrogenated polymerization and hydrogenation can be carried out continuously the reaction is stopped and the dispersion is made using the same solvent during or solution z. By filtration, centrifugation or the whole process. Since the polyeine Similar method for removing the catalyst 5 merisate is not separated before the hydrogenation is treated. The magnetizable catalyst can be very beneficial by adding an antioxidant can be removed by protecting the solution or dating agent. The method can be conti-dispersion after the hydrogenation by a random or discontinuous packing. if is conducted, in which there is a strong magnetic field, which the continuous operation is applied can the hydrogenation catalyst is generated by a permanent or electromagnet using a suitable method, will. A suitable device consists of a with z. B. by centrifugation, separated and then again fine steel wool, thin magnetizable rings or the hydrogenation process. With discount fine magnetisable mesh-filled tube, the catalyst can be separated using a natural working method the outside of which are magnets. The ent and reused as long as it is sufficient magnetization of the filler enables the ent- 15 to be active.

removal of the catalyst particles from the packing. If certain catalyst systems for the butadiene

A suitable form of magnetic separator can be used in the polymerization, e.g. B. those where

U.S. Patent 2,786,047. a metal halide with a Group IV metal

The hydrogenated polymer is then present from the solution, for. B. titanium tetrachloride, should this constituent

medium or dispersion medium separated. 20 part before hydrogenation from the polymer solution

A nickel-kieselguhr catalyst will be removed for the hydrogenation. Any known method can be used

used. Preferably one uses a finely divided one. The polymer can be coagulated,

Catalyst, which has a particle size of 1 to 8 μ, can be washed, redissolved and then hydrogenated,

and at a temperature between 260 and 430 ⁰ C in the catalyst residues, z. B. iodine or chlorine and

In the course of several hours, adding hydrogen over it, ashes, can be removed from the polymer solution by washing

has been activated. This treatment with water, dilute acid or dilute base without

reduces at least part of the nickel compound to coagulate the polymer. if

elemental nickel; In general, 35 to 40% of the procedure is followed, the solution must be prior to the addition of the

of nickel reduced. Hydrogenation catalyst are dried.

The Amount of Hydrogenation Catalyst Used 30 In many cases, both for the polymerization and is 0.1 to 15 percent by weight, preferably 0.5 Ge, also for the hydrogenation, preferably the same percent by weight of solution or more, based on the polymeric agent used; but that is not essential. When a sat weight. low-boiling aliphatic hydrocarbon than

For the hydrogenation, a pressure solvent is generally used for the polymerization, is between atmospheric pressure and 210 kg / cm ² , preferably it is preferable that it is used before the hydrogenation by a range of 7 to 70 kg / cm ² . The temperature can replace higher boiling substance. It is also pull vorvon 20 ⁰ C up to the decomposition temperature of the poly that the hydrogenation does not vary in the presence of a merisats; the maximum temperatures aromatic hydrocarbon solvent being located at 370-535 ⁰ C. temperatures between 120 performs, since both the solvent and the 315 ° C and are preferred. The reaction time is 40 polymer are hydrogenated. Therefore, when an aromatic hydrocarbon is used generally 15 to 24 hours, preferably 15 mi, as the polymerization solvent, up to 3 hours. In order to use polymers with which one replaces them before the hydrogenation to obtain undesirable properties, the uncomfortable should be achieved by cyclohexane, methylcyclohexane or a saturation to a value of about 0 to 30 ° / ₀ , calculated using another suitable solvent.

to the theoretical value of 100% unhydrogenated 45 Apart from the fact that you have another

Polymer, be reduced. Plastics with very product received when the starting polymers of the

interesting properties are in a Unge invention instead of emulsion poly-

saturation of less than 5% obtained. merisaten are used lies in their use

According to a preferred embodiment of the Her- an important, not to be overlooked advantage. In the

position of the new, described here thermoplastic 50 presence of organometallic catalysts produced

Products is butadiene (1,3) in the presence of a polymer do not contain sulfur, such as emulsion

Alkyl lithium catalyst, e.g. B. n-ButyUithium, among polymers.

Use of a solvent such as cyclohexane or Another advantage of using the polymers

Methylcyclohexane, polymerized. The resulting poly of the present invention is that lower

merisate solution is hydrogenated directly. At the end of the poly 55 amounts of catalyst used per polymer unit

merization will be able to inactivate the catalyst.

generally a small amount of water is added. In the thermoplastic products of the present

the system should be best no undissolved water invention are suitable for many purposes. You are good

should be present, and therefore the added water materials for wrapping wire because of their

amount the low ash content necessary to saturate the solvent, its good flexibility and

Do not exceed the amount. For cyclohexane, the amount is said to be easy to extrude and due to the fact

Water does not exceed 0.0094 g per 100 g of cyclohexane. that they are not subject to any stress reduction. Because

The polymer solution can, after the addition of water, its clarity from these polymers very well

can be hydrogenated immediately without intermediate treatment. looking molded articles are produced. she

As there are no components in the polymer solution, it is an ideal material for transparent spray hands that act as catalyst poisons, it is not bottled. You can also use it to make it more transparent necessary to coagulate the polymer and remove films are used and are therefore because of their hertrennen and then it is particularly favorable to restore clarity before the hydrogenation. From these to solve. Films obtained with a smaller amount of polymers can also be used in the heat Hydrogenation catalyst work successfully than at 70 shrink and can be heat sealed.

example 1

Polybutadiene with a Mooney value (ML-4) of 7 was produced according to the following procedure:

Weight
share Butadiene 100
800
0.231
58 to 77
3.2
100 Cyclohexane, technical grade ...
n-butyllithium
Temperature, ⁰ C
Time, hours
Conversion, ° / ₀

Polymerization was carried out in a reaction vessel of 761 content, equipped with a stirrer Removing S ¹ was allowed, with cyclohexane was used as solvent. The polymerization was initiated at 58 ° C; ^{but the temperature rose to 77 °} C. as a result of a high initial reaction rate. After quantitative conversion, the catalyst was inactivated by adding the polymer solution to cyclohexane which contained about 0.1 part of water per 100 parts of monomer. 0.25 parts of trisnonylphenyl phosphite per 100 parts of rubber were added to the solution. The polymer concentration in the solution was 10 percent by weight.

Part of the polymer solution was poured into isopropanol to coagulate the polymer, which was then separated off and dried. A 2.5 percent strength by weight solution of the polymer in carbon disulfide was prepared and the IR spectrum was examined. This study showed 8 ° / ₀ vinyl unsaturation, 47% trans and 45 ° / ₀ cis-configuration, a total of 92% 1,4-addition.

A 38-1 hydrogenation vessel was flushed with nitrogen, and 16.7 kg of polybutadiene solution in cyclohexane with a Content of 1.7 kg of polybutadiene was combined with 1200 ecm of reduced nickel on kieselguhr as a catalyst paste added. The catalyst slurry was prepared in the following way: 250 g of nickel hydroxide Diatomaceous earth was reduced with hydrogen at 413 ° C. for 4 hours with hydrogen and with 1000 ecm of methylcyclohexane offset. The slurry was made up to 2000 ecm with methylcyclohexane. Part of this solvent was used to rinse the equipment and then became the original slurry added. The amount of catalyst added, based on the unreduced compound, was 150 g or 9 percent by weight, calculated on the weight of the polymer used.

After the addition of the polymer solution and the catalyst slurry, the nitrogen gas was mixed with hydrogen driven off and the reaction vessel with hydrogen placed under a pressure of 24.5 atü before heating. The mixture was then heated while bubbling hydrogen into the system to keep the pressure as in FIG shown below.

60

65

70

Time temperature Total pressure Minutes ⁰ C atü 0 Room temperature 24.5 30th 143 24.5 38 185 30.1 45 188 33.9 60 204 35.7 85 221 35.7 100 213 35.0 115 188 - 135 166 32.2 145 166 8.0

After the pressure was reduced to 8 atmospheres, an attempt was made to remove the catalyst by filtering the substance using a pressure filter, but the polymer concentration was too high for a satisfactory process. The mixture was allowed to stand overnight (about 16 hours), and then it was diluted with methylcyclohexane at 8 ° _[0 strength polymer concentration, heated to 150 ⁰ C and filtered using a pressure filter. The filter clogged after about 111 substance had passed through it. The non-filtered part was allowed to stand overnight and then diluted with methylcyclohexane at 5 ° / _o strength polymer concentration, heated to 150 ° C and filtered as before. The hydrogenated polymer obtained from the two filtrations was combined and the physical properties were determined with the following results:

Flow rate ¹ J 1.96

Density ² ) 0.906

crystalline freezing point, ⁰ C ³ ) 90

Slope, at ⁴ ): 79.1

Yield strength, at (compression molded) ⁵ ) 92

Tensile break, at (compression molded) ⁵ ) 229

Elongation at break, ° / o (compression molded) ⁵ ) 917

!) ASTM-D1238-52T. The flow rate is defined as the gram polymer which is ^{pressed out in 10 minutes through a nozzle of 0.21 cm at 190 °} C. under a load of 2160 g. The polymer was pressed out for 5 minutes. The pressed substance was cut off and discarded. Five 30 second sections were then collected, cooled to room temperature, and weighed.

² ) Density values were determined using a density meter following the method of Tung and Taylor, J. Polymer Science, 17, 441 (1955); loc. cit., 19, 598 (1956), and loc. a Ο., 21, 144 (1956). To produce test samples, the polymer from each batch was pressed into a plate in a mold heated to 216 ° C. When the polymer had melted, the mold was cooled to room temperature at a rate of 8.3 ° C. per minute. The disc was then removed from the mold and a piece of the disc about the size of a pea was used for the density determination test. In this test, a tube slightly longer than 1 m with an inside diameter of 4 cm was divided into 1 mm pieces. The tube is then filled with a water-ethanol mixture which has been added in such a way that the ratio of ethanol to water increases progressively from bottom to top. The density of the liquid content thus decreases evenly up the tube. Hollow glass beads of known densities in the range of the density graduation of the tube are placed in the column and these beads settle to a point where their density is in equilibrium with that of the liquid. The positions of the pearls are plotted graphically against density. A sample prepared as just described is dropped into the column and after about 15 minutes the sample comes to rest at a point where its weight is exactly equal to the weight of the displaced liquid. The position is determined and the density can be determined from the graph with an accuracy of ± 0.0002 g / cm ³ . Since the tubes are used at room temperature, the positions of the pearls must be plotted with each approach.

³ ) A polymer sample was melted and a thermocouple was placed in it. The temperature was recorded as the sample cooled. The crystalline freezing point was taken as the midpoint of the plateau of the cooling curve.

⁴ ) ASTM-D-747-50. A Tinius-Olsen stiffness tester was used. Test samples formed from pressed disks were 1.3 cm wide, 11.4 cm long, and about 0.17 cm thick. The test was carried out at 22.78 ° C ± 1.1 ° C. A weight of 113 g was used for this test and the bending span was 5.1 cm.

⁵ ) ASTM-D412-51T. Test specimens were molded from a disk using a Type-C rubber specimen mold. These samples were 11.4 cm long, 0.63 cm wide in the flat test part, and 0.15 cm thick. The stress-strain properties were obtained at 22.8 ⁰ C ± 1.1 ° C. The crosshead speed in these tests was 51 cm per minute. The yield strength is the first stress level on the stress-strain curve at which the slope of the curve becomes zero.

lJie linear contraction of various hydrogenated polymers which were prepared by the same or practically the same method as was shown in this example, was observed from 22 to -200 ⁰ C. When the contraction is plotted against the temperature, there is no evidence of the presence of a freezing temperature (second order phase transition). The unsaturation of these products ranges from 0 to less than 0.2% residual unsaturation.

Example 2

These approaches were used to polymerize butadiene using n-butyllithium as a catalyst carried out. The polymers produced are referred to as A, B and C below. The polymerization regulations and conversion data are then shown.

Parts by weight
B.

Butadiene

Cyclohexane

Butyllithium

Temperature,
⁰ C ( ⁰ F)

Time, hours

Conversion,%

Mooney value
ML-4

Inherent viscosity

Gel,%

IR analysis

Trans,%

Vinyl,%

Cis,%

100 780

0.128 (2 mmol)

57 (135)

2 100

47

7 to 45 to 100
780

0.134
(2.1 mmol)

60
(140)

1
100

33

45

7 to 8
47 to 48

100 780

0.112 (1.75 mmol)

57 (135)

2 100

27

2.06 0

45

7 to 8 47 to 48

A small amount of water was added to each polymerization batch to make the catalyst inactivate, taking care that the added amount of water increases the solubility in cyclohexane did not exceed. To saturate cyclohexane, 0.0094 g per 100 g of water are required. The polymer contains over 90% 1,4-addition product.

The polymers designated as A, B and C were hydrogenated, using the nickel-kieselguhr catalyst described in Example 1 was used. Two approaches were carried out with polymer A, with different amounts of hydrogenation catalyst were used. A 1700 cc reaction vessel was used for the hydrogenation stainless steel equipped with a stirrer was used. The polymer solutions obtained from the polymerization batches were for the hydrogenation used without the polymers being separated off and redissolved. The following Amounts of substance were added to each batch.

Attempt no. 3 4th 1 2 I. C. A. A. B. 600 400 700 400 - 49.6 86.8 88 95 16 95 96 13th 2 13th 13.2 - 4th 15th 15th 305 584 205 504 1000 1000 1000 1000

Polymer used

Polybutadiene solution, ecm

Weight of polybutadiene, g

Catalyst slurry, ecm

Unreduced nickel on kieselguhr, g

Weight percent catalyst ¹ )

Methylcyclohexane flush, ecm

Total volume of the batch, ecm

') Calculated on the added polymer weight.

In each experiment, the reaction vessel was flushed with nitrogen, the ingredients added, the reaction vessel Pressurized twice with nitrogen to 14 atmospheres pressure and vented to 0 atmospheres and then twice with Bring hydrogen to 14 atmospheres pressure and vented to 0 atmospheres. According to this procedure, the reaction vessel was pressurized to 24.5 atmospheres with hydrogen and started heating. Hydrogen was introduced into the system to maintain the pressure as shown. In detail, the following procedure was used for each approach:

Attempt I.

Time temperature Total pressure Minutes ⁰ C atü 0 Room temperature 177 22nd 93 199 34 163 201 40 199 260 62 232 260 97 232 260 127 232 260 172 232 260 267 232 260 277 149 260

The mixture was diluted with 800 ecm of methylcyclohexane, heated to about 71 ° C. and removed to remove the Catalyst passed through a magnetic separator. The polymer was precipitated by dissolving it in isopropanol was poured and it was collected by filtration using a Buchner funnel. It was Dried for 15 hours at 100 ° C. in vacuo. 53 g of white plastic insoluble in cold methylcyclohexane became obtain. The material is transparent after pressing.

Experiment II

Time temperature Total pressure Minutes ⁰ C atü 0 Room temperature 24.5 26th 110 29.7 41 185 30.8 56 218 35.7 61 229 35.7 86 232 35.7 111 232 35.7 146 232 35.7 181 232 35 271 232 34

The reaction mixture was removed from the reaction vessel, which was then rinsed with 1 liter of methylcyclohexane became. The rinse liquid and another 1.5 liters of methylcyclohexane were added to the reaction mixture. That Material was heated to about 70 ° C and passed through a magnetic separator to remove the catalyst. The polymer was precipitated, filtered and dried as in Experiment I. A white plastic product (28.5 g) was obtained. The material is transparent after pressing.

Experiment III

10 Time temperature Total pressure Minutes ⁰ C atü 0 Room temperature 24.5 19th 99 27.3 34 160 27.3 44 196 26.6 2o 54 232 35 79 232 35.7 129 232 35.7 164 232 35.7 ²⁵ 204 229 43.3 269 232 35

The reaction mixture was removed from the reaction vessel, diluted with methylcyclohexane, the catalyst removed and the polymer, as described in Experiment II, precipitated and filtered. The product was 5 hours at 100 ° C dried in vacuo. 43 g of white plastic product was obtained. The material is transparent after pressing.

Experiment IV

Time temperature Total pressure 45 Minutes ⁰ C atü 0 Room temperature 24.5 30th 99 24.5 50 65 232 35 105 232 35 160 232 34.3 190 232 34.3 55 220 232 35 285 232 35

The reaction mixture was removed from the reaction vessel, which was then rinsed with 1 liter of methylcyclohexane. The rinse liquid and another liter of methylcyclohexane were added to the reaction mixture. After heating at 7O ⁰ C, it was passed through a magnetic separator to remove the catalyst. The polymer was precipitated by pouring the solution into isopropanol. It was filtered and dried in vacuo at 100 ° C. for 15 hours. A white plastic product (35.5 g) was obtained. The material is transparent after pressing.

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The physical properties were determined for all four hydrogenated polymers. The following results were received:

Mooney value (ML-4) of the starting polybutadiene percent by weight of catalyst in the hydrogenation

Unsaturation, ⁰ I ₀ ¹ )

Intrinsic viscosity ² )

Flow velocity ³ )

Density ¹ )

Crystalline freezing point, ⁰ C *)

Stiffness, at ⁴ )

Yield strength (compression molded), at ⁴ )

Tensile break (compression-molded), at ⁴ )

Elongation at break (compression-molded), ° / ₀ ⁴ )

Young's modulus, at ⁵ )

4.5
15th

<0.2
1.68
1.62
0.9113
± 0.56
0.87
94
207
867
1.02

33

15th

1.60
1.55
0.9144
98

1.19
102
213
990
1.23

27

1.66 1.31 0.9109 95 0.87 102 229 1000 1.02

4.5 4 <0.2

1.03 0.9090 95 6.65 93 226 960 0.88

¹ J The unsaturation was determined by adding 0.2 g of solid polymer to 50 ml of cyclohexane and ^{heating the mixture at 80 °} C. for 4 hours to dissolve the polymer. The solution was cooled to room temperature (about 25 ° C) and excess iodine monochloride dissolved in purified chloroform was added. The mixture was made up to 250 ml by adding a 75:25 mixture (volume) of CS ₂ and chloroform. It was placed in a constant temperature bath at 25 ° C for 1 hour; then a portion of 25 ml was removed and the iodine was titrated with sodium thiosulphate.

² J A solution of 0.1000 g of polymer in 50 ml of tetrahydronaphthalene was prepared, the solution was brought to a temperature of 130 ^o C ± 0.2 ° C and the time in seconds was determined for it to flow from the upper to the lower marking of a Ostwald-Fenske viscometer was required. The value was compared with that obtained for tetrahydronaphthalene alone.

³ ) The procedure described in Example 1 was followed, except that five 1 minute intervals were collected in Runs I and IV. In Trials II and III, five 30-second segments were collected. All collected coupons were then cooled to room temperature and weighed. An average of the five values from each experiment was obtained and the flow rate calculated.

') As in example 1.

■ *) Tensile specimens were used. The crosshead speed was 0.13 cm / minute and the chart speed 1.3 cm / minute.

Example 3 different degrees of unsaturation hydrogenated. The at

Polybutadiene was produced according to the following rule: the amounts of material used in each experiment posed: then stated:

Butadiene

Cyclohexane

n-butyllithium

Temperature, ⁰ C ( ⁰ F).

Time, hours

Conversion, ° / ₀

Mooney value (ML-4)

Parts by weight

100

780

0.32 (5, OmMoI) 60 (140) 3 quantitative

too low to measure the value

0.83 0

Intrinsic viscosity ¹ )

Gel,%

¹ J As in example 2.

The polymer, which contained over 90 ° / ₀ 1,4-addition product, was using the nickel-kieselguhr catalyst described in Example 1 to two

Polybutadiene solution, ecm

Weight of polybutadiene, g

Catalyst slurry, ecm

Unreduced nickel on kieselguhr, g

Weight percent catalyst,
calculated on the weight of the polymer

Added cyclohexane, ecm ..

Volume of the total quantity, ecm ...

Attempt no. '

900

65

100

12.5

19th

1000

I I 57.6 j 4.6

1.0 200 1004.6

The same procedure as described in Example 2 was used for hydrogenation. Details of the experiments are given in the following table emerged.

Attempt I.

Time temperature Total pressure Time temperature Total pressure Minutes ⁰ C atü Minutes ° C atü 0 Room temperature 25.9 0 Room temperature 28 12th 49 31.5 28 132 34.3 25th 110 31.5 58 232 35 55 232 35 88 232 35.7 105 232 35 118 232 35.7 155 232 35 183 232 35 205 232 35 198 232 35 285 149 268 152

In experiment I the filtrate was cooled to 10 ° C. The polymer precipitated and was separated by filtration using a Buchner funnel. It was dried in vacuo at 100 ° C. for 7 hours. It became a white plastic product of 54 g Weight received.

Immediately after the filtration, in experiment II, 0.06 g of 4,4'-butylidene-bis- (6-tert-butyl-m-cresol) added to the filtrate, which was then poured into isopropanol to precipitate the polymer. That Polymer was filtered and dried at 100 ° C. in vacuo for 15 hours. It was a white plastic Material weighing 50 g. Both tests resulted in a material that is transparent when pressed.

The physical properties were determined for each product. The following results were obtained :

I. II Unsaturation,%
Flow rate
density 5.1
13.54
0.9135
95 ± 0.6
108
42 24.6
0.57
0.9101
94 ± 0.6
75
23.1 Crystalline freezing point, ⁰ C
Tensile break (compression-molded), at
Elongation at break (pressure
pressed), at

Example 4

The procedure of Example 1 is repeated using a mixture of 70 parts (1.3) butadiene and 30 parts by weight styrene to obtain a synthetic rubber. This butadiene-styrene copolymer is hrydiert according to Example 1 to a residual aliphatic unsaturation of about 5 ° / _0th The hydrogenated product has essentially the same properties as the hydrogenated polymer from Example 1.

In the examples, the type of unsaturation was determined by IR analysis of the polymer, which is not an antioxidant determined by forming a 2.5 weight percent solution in carbon disulfide. If that Polymer contained antioxidant, it was made by precipitating the polymer twice from cyclohexane removed from the preparation of the carbon disulfide solution.

In the IR analysis, the band used to determine the trans-1,4 unsaturation was 10.3 μ and the maximum absorption band used to determine vinyl unsaturation 11.0 μ. The IR spectra were made using a Perkin-Elmer Model 21 spectrophotometer recorded, which was equipped with a sodium chloride prism. Compensation for that Carbon disulfide solvent was obtained by placing a cell filled with carbon disulfide in the reference beam.

The absorbance values of trans-1,4 and vinyl unsaturation were determined for the 10.3 and ΙΙ, Ο-μ bands by determining the log (I _o / I), where I ₀ and I are the intensities of the incident and transmitted radiation. The procedure gives average deviations of up to 0.2 ° / ₀ with an estimated accuracy of 2 ° / ₀ .

All Mooney values were determined at 100 ° C.

Claims (5)

Patent claims: 1. A process for the preparation of a hydrogenated butadiene-homo- or butadiene-styrene copolymer by hydrogenating the dissolved polymer with hydrogen in the presence of a hydrogenation catalyst, characterized in that the starting polymer is a homopolymer of butadiene (1,3) or a copolymer of Butadiene (1,3) and not more than 30 percent by weight styrene, in which at least 90 ° / _{0 of} the butadiene units in the polymer are bonded by 1,4-addition, used and the hydrogenation continues until the unsaturation to one value / ₀ Ausgangsungesättigtheit is reduced by less than 30 °. 2. The method according to claim 1, characterized in that there is a hydrogenation catalyst Nickel-diatomaceous earth catalyst used. 3. Process according to Claims 1 and 2, characterized in that the hydrogenation is carried out at a Temperature from 120 to 315 ° C executes. 4. Process according to claims 1 to 3, characterized in that the hydrogenation is carried out at a Pressure between 7 and 70 atm. 5. Embodiment according to claims 1 to 4, characterized in that a polymer solution, by polymerizing the monomer or monomers in the presence of an alkyl lithium catalyst using a cycloparaffin solvent and its catalyst by The addition of an insufficient amount of water to saturate the solvent has been inactivated, hydrogenated directly. Documents considered: French Patent No. 1,051,499; "Rubber Chemistry and Technology", Vol. 31, pp. 156 to 165. © 10i 607/444 5.61