DE2821342A1 - PROCESS FOR PRODUCING A THERMOPLASTIC ELASTOMER POLYMERIZATE - Google Patents

Description

The present invention relates to a method of manufacture a thermoplastic elastomeric polymer mixture consisting of polypropylene, polyethylene and an ethylene-propylene polymer.

Such polymer mixtures are from the American patent 3,957,919 known. In this patent it is described that adding a small amount of polyethylene to a polypropylene and Ethylene-propylene copolymer existing mixture has the negative influence the crosslinking agents incorporated into the mixture, which decompose at the elevated temperature during mixing, are able to eliminate. The resulting crosslinked mixtures have a particularly low melt index, so that they can almost not be processed by injection molding. The American patent 3,919,358 describes the production of mixtures known from ethylene-propylene copolymers and polyethylene, wherein the crystallinity of the ethylene-propylene copolymer is at least 10% and the density of the polyethylene is less than 0.94. These are easy to process Polymer mixture.; However, they have less good mechanical properties. In particular the resistance to high temperatures and the impact resistance at low temperatures leave something to be desired. Even the permanent one Deformation, rigidity and hardness are unsatisfactory. Furthermore, the American patent 3,941,859 describes the production of mixtures of ethylene-propylene copolymer, polyethylene and an ethylene-vinyl acetate copolymer known. In this case too, the crystallinity of the ethylene-propylene copolymer should be more than 10%. In both of the latter

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th patents it is noted that ethylene-propylene copolymers with low crystallinity in mixtures with other polyolefins such as polyethylene cannot lead to good properties.

It has now been found that thermoplastic elastomeric polymer mixtures, which made of polypropylene, polyethylene and an ethylene-propylene polymer exist, can be produced, which can be processed very well and also have good mechanical properties. In addition a mixture is made from:

A. 30 to 75 tsp. of a crystalline, isotactic propylene homopolymer with a melt index between 1 and 25 dg / min and

B. 25 to 70 Tlen. a rubbery ethylene-propylene polymer with

a crystallinity of less than 10 wt .-%, an ethylene content of more

2 than 58%, a tensile strength of more than 30 kg / cm and a Mooney viscose

ity (ML [l + 4 ~ \ 125 ° C) of minimum 30 and maximum 90, where

C. maximum 15 tie. of the propylene homopolymer and at least as many parts as by half of the numerical value of the melt index of the propylene homopolymer is specified, are replaced by as many polyethylene parts with a density between 0.91 and 0.98 g / cm.

The polymer mixtures according to the invention have a melt index which is many times greater than the melt index according to the American one Patent 3,957,919 obtained mixtures while the mechanical properties are at least equally good. The mixtures according to the invention are suitable. excellent for injection molding processing. The combination of their properties (very good processability, high impact strength at low temperature, resistance to high temperatures, great rigidity) extremely cheap, while the cost price is relatively low.

The invention basically consists of getting through the right Choice of the individual ingredients a mixture with a surprising and has known how to produce an extraordinarily attractive package of properties. In contradiction to the current state of the art, one has for Use of an ethylene-propylene polymer with, among other things, low crystallinity decided. The resulting shortcomings in relation to E.g. the rigidity and the resistance to high temperatures could be compensated by using a propylene homopolymer. To the To remedy the associated brittleness at low temperatures, a small amount of polyethylene caused by the melt index of the polypropylene was used added to the mixture. It was also found that the ethylene-propylene polymer must meet a number of other requirements in order to give the mixture according to the invention the desired favorable combination of properties

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to lend stocks.

The ethylene-propylene polymer used according to the invention preferably has an ethylene content of at least 61% by weight. It is known that the tensile strength of the ethylene-propylene polymers also increases sharply with increasing ethylene content. However, especially with an ethylene content of more than 77% by weight, the crystallinity can increase sharply, which has an unfavorable effect on a number of properties, such as the compression set and the toughness at low temperatures. The ethylene content is therefore preferably chosen below 77% by weight and in particular below 75% by weight. Another advantage of this is the improvement in elongation at break. The best results are achieved when the ethylene content is chosen to be less than 70% by weight. Ethylene-propylene polymers with a high molecular weight generally give mixtures with other polyolefins better mechanical properties, but at the same time reduce processability. Very good properties are found when the ethylene-propylene copolymer has a maximum Mooney viscosity (as a measure of the molecular weight), which is due to the melt index of the propylene homopolymer. This maximum value for the Mooney viscosity results from the equation ML = 90 - ■ 7ΓΈ ' - * - ⁿ ^ ^{er m} · ^

m.i. * Q represents the melt index of the polypropylene in. Dg / min, measured at 230 ° C.

and 2.16 kg. The Mooney viscosity (ML Pl + 4J) is measured at 125 C. The Mooney viscosity is preferably not higher than one determined by the

Equation ML = 90 —— selected value because the processing

^MAX i ° ⁶

L ^MAX

m.i.

m ..
performance properties are optimal in this case, while the rest are good

Properties are retained. A table is included for explanation, from which it is easy to read how large the maximum value of the Mooney viscosity at a certain melt index of the propylene polymer

sats is preferably.

Maximum Mooney viscosity of the ethylene-propylene polymer melt index

Polypropylene

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Melt Index Preferred Limit Most Preferred Limit Polypropylene

90 -

. 0.6. 0.6

m.i. m.i.

dg / min

1 40

2 57 .24

3 64 38

4 68 46

5 71 52

6 73 56

7 74 59

8 76 61

9 77 63

10 77 65 15 80 70 20 82 73 25 83 75

The ethylene-propylene polymer used according to the invention also has a crystallinity of a maximum of 10% by weight. An amorphous ethylene-propylene copolymer is preferably used, i.e. a copolymer with a crystallinity of less than 4% by weight and in particular of less than 1% by weight. Thereby the compression set and the Greatly improved toughness at low temperature.

Furthermore, the rubber-like ethylene-propylene polymer preferably has

2 a tensile strength in the unvulcanized state of more than 50 kg / cm. The crystallization temperature of the polymer, recorded by means of differential scanning calorimetry ¹ , is preferably above 0.degree. C. and in particular above 10.degree.

The ethylene-propylene polymer can be used in an amount of a maximum of 20% by weight contain a polyunsaturated monomer. These multiply saturated Monomers are usually non-conjugated polyenes, especially dienes. They are mostly used in amounts of a maximum of 10% by weight. Examples for such monomers are dicyclopentadiene, alkylidene norbornene, alkenyl norbornene, Alkadienes and Cycloalkadienes »Preference is given to dicyclopentadiene, Ethylide Gnnorbornene, Norbornadiene, 1,5-Hexadiene, 1,4-Hexadiene and mixtures these substances are used. The ethylene propylene used according to the invention

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Polymers can be prepared in a conventional manner, for example using that in British patents 1,014,873, 95Ί.022 and 880,904 described procedure. For further details on this production, reference is made to the unpublished Dutch patent application 7,610,672 referenced.

The crystalline, isotactic propylene homopolymer used according to the invention has a melt index between 1 and 25 dg / min and preferably between 1.5 and 20 dg / min. A melt index is particularly preferred between 5 and 15 dg / min. In the present invention, this melt index determines the preferred maximum value of the Mooney viscosity of the ethylene-propylene polymer and the amount of polyethylene to be added. The density of the propylene homopolymer used is preferably between 0.900 and 0.910 g / cm.

In the unpublished Dutch patent application 7.610.672 it is described that an ethylene-propylene copolymer with a specific propylene block copolymer can be mixed, which mixture has very good mechanical properties. With the help of the procedure according to the present invention, these properties can be exceeded will. So have the products using the inventive Process can be produced, a better hardness, a better tensile strength and a better resistance to high temperatures than that in the the above-mentioned Dutch patent application. Other properties, such as toughness, remain at the same level. Further advantages are the better tensile strength and the lower thermal Shrinkage. The high melt index, which can be achieved with the aid of the method according to the invention, is of particular importance. To do this must a polypropylene with a sufficiently high melt index can be used. This also improves the other mechanical properties. That too This causes brittleness at low temperature surprisingly completely eliminated if a larger part of the polypropylene is replaced by polyethylene, i.e. by a quantity of polyethylene, whose numerical value is at least half, but preferably at least 3/4 of the melt index of the polypropylene. It is very surprising by application a polypropylene homopolymer in combination with the correct one Amount of ethylene polymer such greatly improved properties can be obtained.

The polypropylene used according to the present invention is basically isotactic and has a high crystallinity, preferably more than 50% by weight, measured by means of X-ray diffraction. It can be done using the

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well-known processes, mainly based on the use of of modified or unmodified titanium chloride, which is activated, e.g. with an aluminum compound. The third after the present Invention to be included in the mixture component is an ethylene polymer with a density between 0.91 and 0.98 g / cm and preferably a melt index between 0.1 and 35 dg / min. Preferably the density is greater than 0.94 g / cm and in particular greater than 0.96 g / cm, which means that no or only a small amount of comonomer was added to the polyethylene e.g. less than 0.5% by weight.

For the thermoplastic elastomer mixture according to the invention a composition of 50 to 70 parts. crystalline, isotactic propylene homopolymer and 30 to 50 parts. rubber-like ethylene-propylene polymer preferred. When using undersize ethylene-propylene polymer the special effects of the invention are shown to their best advantage. The rigidity and the properties at high temperature are high in this case. The improvement in impact resistance at lower Temperature with the help of the ethylene polymer is particularly pronounced, the processability in this composition is very good, while the other properties are optimal.

The thermoplastic mixtures can in a known manner with the aid the usual equipment for plastics such as rollers, extruders, high-speed mixers and kneaders, whereby the plastic material at elevated temperature, especially at a temperature between 150 and 220 ° C, shear forces is exposed. For use on an industrial scale, kneaders and extruders are preferred, in which mixing at temperatures of approx. 180 to 220 ° C takes place.

All kinds of additives can be used in the mixtures according to the invention be recorded, such as dyes, lubricants, fillers ,. Antioxidants, UV stabilizers, flame retardants, zinc oxide and / or magnesium oxide, fibers or combinations of fibrous and powdery substances without the specific properties are lost. In particular, soot and / or 01 can be added to the mixture.

The polymer mixtures according to the invention can also be used with others Polymers such as styrene polymers, polyamides, polyvinyl chloride, polycarbonates, Block copolymers of styrene and butadiene, which may have been hydrogenated, chlorinated polyolefins such as chlorinated polyethylene, and Mixtures of these polymers are mixed. You can also improve the impact strength of other polymers can be used. The inventive Mixtures of polymers can be used for numerous purposes

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because they are as soft and rubbery as they are stiff and impact-resistant can. The mixtures are particularly suitable for the production of larger objects, that are used outdoors, e.g. for automobile bumpers.

The thermoplastics made in accordance with the present invention Elastomers are extremely weather-resistant. This weather resistance can be further improved by adding UV stabilizers and / or zinc oxide to the mixture, especially if no carbon black is used be included, if necessary in addition to a phenolic antioxidant. as The UV stabilizer is preferably a combination of a so-called UV quencher, in particular a disturbed amine, and a UV absorber, such as a benzotriazole and benzophenone compound are used.

Example I.

In a kneader, a series of ethylene-propylene polymer, Polypropylene and possibly polyethylene existing mixtures of the composition shown in Table 1 produced. An ethylene-propylene terpolymer rubber, referred to as EPDM I, which contains 64% ethylene, 30% propylene and 6% ethylidene norbornene. The tensile strength

2 speed in the unvulcanized state is 65 kg / cm. The Mooney Viscosity (ML [1 + 4] 125 ° C) is 52 and the crystallinity is below 0.25%. The propylene polymer referred to as PP I is a block copolymer of propylene with 7% ethylene, a density of 0.905 and a melt index (230 C, 2.16 kg) of 6.0 dg / min. The propylene polymer referred to as PP II is a propylene homopolymer with a density of 0.905 g / cm and a melt index of 5.2 dg / min (230 ° C, 2.16 kg) ;. That in the table with Polyethylene designated PE I has a density of 0.963 g / cm and a melt index of 8 dg / min (190 ° C, 2.16 kg).

To carry out the experiments given in Table I, the rubber-like Ethylene-propylene polymer brought into the kneader. After 1 minute The polypropylene and the polyethylene are added to the kneading. After 4 minutes of kneading (total time 5 minutes), approx. 30 minutes are left without stamping kneaded; then kneading is continued until a temperature of approx. 170 ° C. is reached. Plates are injected from the mixtures, which on the properties specified in the table are checked. The table also includes the properties of two commercial products.

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Table 1

Sample no.

Commercial commercial product A product B

1 2

EPDM I PP I PP II PE I.

40 40 40 40 40 35 35 60 - - - - 65 55 - 60 57% .55 50 - - 2h 5 10 10

Melt index (dg / min)

Hardness (shore D) Vicat temp. 1 kg (0 ⁰ C) • heatsagtest ¹ (mm)

9.1

53

97

34.5

5.2

48

100

34.0

10.5 8.5 7.8 7.2 5.9 12.5 7.6 50 55 54 54 53 53 54 105 127 122. 118 107 119 103

28.5 -

25.5 25.5

Flat fall test on flow seam

Breaking energy (Nm) 3.16 3.62 3.50 2.70 2.94 3.37 3.74 3.20 3.72 Force (N) 1329 1442 1404 1485 1468 1511 1474 1439 1438 Type of break tough tough brittle
de brittle
de brittle
de tough tough brittle
de Brittle/
tough Tensile strength
(N / nm) 71 61 69 77 78 76 75 70 73

The various properties are measured using the following standards:

Melt index ASTM D-1238 (230 ° C, 5 kg)

Hardness ASTM D-2240 (reading after 3 seconds)

Tensile strength NEN 5602, test bar 2, elongation rate 15 cm / min Vicat temperature ASTM D-1525, load 1 kg

Heatsagtest test rod 10 χ 1 χ 0.16 cm, heat load 1 minute at 120 ° C

Flat fall test after 48 minutes of conditioning, weight 5 kg, height of fall

1 m, impact speed 4.2 m / sec. Has the drop weight a flat impact surface with a diameter of 1 cm. The test plate with a thickness of 1.6 mn is from a Supported ring with a diameter of 2 cm.

Tensile strength

Thermal shrinkage

DIN 53515

DIN 53497, heat load 24 hours at 90 C.
The end. The table shows that mixtures with PP homopolymer (samples 2, 3, 4, 5) are considerably better resistant to high temperatures than the

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same sample 1 with PP copolymer. Resistance to high temperatures is also considerably better than that of the 2 comparable commercial products. For the favorable combination of toughness at low temperature (high fracture energy, tough break) and good resistance to high temperatures, the addition of PE is essential. Samples 2, 3, 4 and 5 show that the PE content for sufficient toughness at low temperature Must be at least as high as half the numerical value of the melt index of the PP homopolymer is specified. Good resistance to high temperatures can also opolymer with a relatively high content of PPH ^ (Sample 6), however, in this case, the toughness at low temperature is insufficient. The toughness at high temperature can be increased by adding Although PE can be increased to an acceptable level, this has an effect however, the resistance to high temperatures is so unfavorable that the mixtures ultimately do not improve compared to the commercial products (Sample 7) show.

Example 2

The mixtures mentioned in Table 2 are mixed in a laboratory kneader (Brabender Plastograph) at a kneading chamber temperature of 180 C and a kneading time of 10 minutes. All components of the mixture are simultaneously brought into the kneading chamber. The mixtures are then rolled and pressed into panels at 200.degree. The components that make up the mixture are has already been described in Example 1, with the exception of PP III, a PP homopolymer with a melt index of 1.3 dg / min and a density of 0.905 g / cm. From Table 2 it can be seen that Samples 1-5 passed through a higher hardness, greater rigidity at room temperature, greater tensile strength and a higher tensile strength differ from Samples 6-7. These facts show that mixtures with a PP homopolymer have better mechanical properties than mixtures with a PP copolymer.

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Table 2

1 2 3 4th 5 6th 7th Sample no. 47 ¹ p 45 40 47 ^ 45 Mh 45 EPDM I - - - - - 50 50 PP I 50 50 50 - - - - PP II - - - 50 50 - - PP III 2 ^ 5 10 2h 5 2 * i 5 PE I 1.0 1.2 1.3 0.46 0.49 1.3 1.6 Melt index (190 C-IO kg) g / min 51 52 53 51 53 46 47 Hardness (shore D) 2.30 2.43 2.69 2.13 2.39 1.39 1.45 —9 2
G 'χ 10 (Dyne / an) 73 83 84 83 83 57 61 Tensile strength (N / mm) 9.9 10.0 10.6 9.8 10.9 7.4 6.1 Tensile strength (MPa) 160 150 100 270 290 300 280 Elongation at break (%)

The properties are measured according to the following standards or methods:

Melt index ASTM D-I228 (190 ° C, 10 kg)

Hardness ASTM D-2240, reading after 3 sec.

Rigidity (G ¹ ) torsional damping f = 0.2 H, 22 ° C tensile strength DIN 53515

Tensile strength NEN 5602, test bar 2, expansion rate 30 cm / min

Example 3

This example shows that the Mooney viscosity of the ethylene-propylene copolymer to enable problem-free processing with the aid of injection molding techniques, one through the melt index of the PP homopolymer conditional maximum "value.

In a Brabender plastograph, 40 parts by weight. Ethylene-propylene terpolymer (EPDM), 55 parts by weight. PP homopolymer and 5 parts by weight. Low pressure polyethylene mechanically mixed together in the manner described in Example 2. Both the Mooney viscosity of the EPDM like the melt index of EPDM and the melt index of PP homopolymer varies. Three ethylene-propylene terpolymers with a Mooney viscosity (ML ^ l + 4 ^ 125 ° C) of 39, 52 and 62 are each made with three types of PP homopolymer with a melt index of 1.3, 5.2 or 9.5 dg / min (230 C, 5 kg) mixed. The melt indices of the mixtures are given in Table 3. For the mixtures examined, the maximum value preferably used is the Mooney viscosity of the EPDM as a function of the melt index of the PP homopolymer following:

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Melt index of PP homopolymer (dg / min)

Maximum Mooney viscosity of EPDM 50

preferred maximum limit

the Mooney viscosity of the EPDIi 100

m.i.

0.6

= 90 -

m.i.

0.6

1.3 5.2 9.5

47
71
77

preferably not use.

It can be seen from Table 3 that the Mooney viscosity of EPDM in the samples

6 and 9 is greater than the preferred maximum value. These samples have for good processability too low a melt index. The remaining samples have a sufficiently low Mooney plasticity and consequently have the mixtures have a melt index such that good processability is guaranteed. Samples 1, 2, 4 and

7 found. The processability of samples 3 and 8 is critical for applications not suffice.

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Tabel

SAMPLE NO.

Mooney viscosity EPDM ML (1 + 4) 125 C

V »

Melt index PP homopolymer 230 C / 2.16 kg

(dg / min)

39 39 39 52

52 52

62

62

9.5 5.2 1.3 9.5 5.2 1.3 9.5 5.2 1.3

COMPOSITION OF THE MIXTURE

EPDM II EPDM I EPDM PP IV * PP II PP III PE I

40

55

55
5

40

55

40

55 5

40 55

40

55

Melt index 230 C / 5 kg (dg / min)

14.5 9.9 4.5 ² 11.2 7.8 ³ 3.5 * 8.2

5.9 ² 2.7 *

EPDM II: 63% by weight of ethylene, 5% by weight of ethylidene-1. Poor processability in the injection molding process
nen ₂

^ Tensile strength 49 kg / cm, crystallinity 2. Unsuitable for critical applications where good
^J < 0.25% workability required. is.

3. Processability just good enough for injection molding compli-

EPDM III: 62% by weight of ethylene, 5% by weight of ethylene-denoted molded parts.

nen ϊν>

Tensile strength 55 kg / cm, crystallinity 00

<0.25% KJ

PP IV

DSC temperature +8 C

Polypropylene homopolymer melt index
(230 ° / 2.16 kg) 9.5 dg / min
Density 0.905 g / cm3

Example 4

The mixtures listed in Table 4 with a polypropylene homopolymer with a melt index of 9.5 dg / min were produced in the manner described in Example 1. The samples will, however under different conditions, i.e. at higher temperature and lower pressure, sprayed to form sheets. As a result, the test results are not quite consistent comparable to those of the previous example.

From Table 4 it can be seen that with a propylene homopolymer with With a melt index of 9.5 dg / min, mixtures can be produced which have high toughness at low temperatures. It is probably in addition It is necessary that the amount of PE is at least approximately 5% by weight, i.e. more than half the numerical value of the melt index of the PP homopolymer is specified.

Table 4

SAMPLE NO. 12 3 4

COMPOSITION EPDM I
PP IV
PE I

40 40 40 40 60 57 * 5 55 50 - 2h 5 10 14.3 12.4 10.0 7.8 56 56 56 54 83 82 80 80 3.2
1622
brittle 3.7
1616
brittle 3.9
1616
brittle/
2, uh 4.1
1609
tough 18.1 19.1 17.1 17.1 15.6 16.6 15.7 15.2 20.2 19.6 19.6 19.6 470 450 470 440

PROPERTIES

Melt index 230 ° C - 5 kg (dg / min) hardness (Shore D) tensile strength (DIN 53515 (N / mm))

Instrumented flat fall test (-40 C) for flow seam fracture energy (Nm)

-Max. Force (N)

-Type of break

Yield stress (N / mm)

Stretching tension (N / mm)

Tensile strength (N / mm) Elongation at break (%)

Example 5

This example shows that the advantages described in the invention the addition of polyethylene can be canceled due to an excessively high polyethylene content. The mixtures listed in Table 5 are mixed in the kneader the manner described in Example 1 prepared. Samples 1, 2 and 3

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are all easy to process, mixture 4 with 20 wt .-% PE has a high polyethylene content and has too low a melt index. The tensile strength is also unsatisfactory.

Table 5

1 2 3 4th Sample no. 35 35 35 35 EPDM I 62 * 5 60 55 45 PP II 2J ₅ 5 10 20th PE I 10.1 9.0 7.2 2.5 Melt index (dg / min) 57 57 56 56 Hardness (Shore D) 12.9 12.5 11.4 9.8 2
Tensile strength (N / mm) 175 255 250 250 Elongation at break (%) 125 123 119 110 Vicat temperature Example 6

In this example it is shown that the density of the polyethylene also influences the effectiveness of the polyethylene as a means of improving the mechanical properties can be important. Be in a kneader 40 tie. EPDM 1,55 Tie. PP 1 and 5 TIe. Polyethylene mechanically on the in Example 1 described manner mixed together. The following PE types are used in the 5 mixtures:

Density melt index (190 °, 2.16 kg) (dg / min)

PE I. 0.963 g / cm 8th 3 PE II 0.953 24 4th PE III 0.948 Θ, 5 PE IV 0.953 1, PE V (LDPE) 0.918 7,

The samples are used to determine their properties based on the example 4 sprayed manner to plates described. These properties are given in Table 6.

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Table 6 ^ *

PRQBE NO. 12 3 4

COMPOSITION

EPDM I PP II

PE II PE III PE IV PE V (LDPE)

40 40 40 40 40 55 55 55 55 55 5 _ _

PROPERTIES

Melt index 230 C-5 kg (dg / min) * hardness (Shore D) Tensile strength DIN 53515 (N / mm) Instrumented flat fall test (-40 C)

on continuous seam fracture energy (Nm) -Max. Force (N) fraction type Yield stress (N / mm ^)

2 stretching tension (N / mm)

2 tensile strength (N / mm) elongation at break (%)

5.2 5.9 5-, 5 5.3 5.7 54 53 54 54 53 75 73 75 74 74 4.0 4.2 4.0 4.2 3.9 1649 1623 1639 1631 1586 tough tough tough tough tough 18.4 17.8 18.5 18.3 17.6 17.0 16.0 17.0 16.6 16.5 21.3 21.6 21.1 20.9 21.0 430 420 430 420 420

Table 6 shows that when using polyethylene with a density higher than 0.94 g / cm better results can be achieved. The best combinations of properties are found at a density greater than 0.96 g / cm.

Example 7

In the manner described in Example 2, in the Brabender plastograph Mixtures of 40 parts by weight. Ethylene-propylene terpolymer, 55 parts by weight. Propylene homopolymer and 5 parts by weight. Made of polyethylene. Afterward the mixtures are rolled and pressed at 200 C to form sheets. 4 mixtures are made. There are 3 mixtures of 'greenstrength' EPDM types used. Reference is made to Table 7 for the properties of the mixtures.

The table shows that the mixture with non-'green-strength' EPDM (sample 1) differs from the mixtures with 'green-strength ¹ -EPDM (samples 2, 3 and 4) in terms of lower hardness, tear strength and tensile strength.

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To take full advantage of the advantages described in the present invention To be able to use a "green strength" EPDM is required Ethylene contents lead to low elongation at break (sample 3).

Table 7

SAMPLE NO. 12 3 4

COMPOSITION

EPDM IV EPDM I

40

EPDM V

2)

EPDM VI PP II PE I

3)

55
5

40

55 5

FEATURES ' 7.3 7.8 6.5 6.5 Melt index 230 ° C-5 kg (dg / min) 49 55 55 55 Hardness (Shore D) 75 89 99 95 Tensile strength DIN 53515 (N / nm) 10.4 11.9 12.6 12.4 2
Tensile strength (N / mm) 110 130 80 130 Elongation at break (%)

1) EPDM IV: ethylene content 55% by weight, ethylidene norbornene 5% by weight, tensile strength 2.4 kg / cm, crystallinity <0.25%, Mooney ML (1 + 4) 125 ° C: 54,
DSC temperature -17 ° C

2) EPDM V: ethylene content 75% by weight, 1,4-hexadiene 3% by weight, tensile strength 124 kg / cm, crystallinity 8%, Mooney ML (1 + 4) 125 ° C: 64, DSC temperature + 38 ° C

3) EPDM VI: ethylene content 70% by weight, ethylidene norbornene 4.5% by weight, tensile strength 120 kg / cm ² , crystallinity 3%, Mooney ML (1 + 4) 125 ° C: 61, DSC-Tem-

O
temperature +24 C.

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Claims (19)

PATENT CLAIMS 1. Process for the production of a thermoplastic elastomeric polymer mixture, which consists of polypropylene, ethylene-propylene polymer and polyethylene, characterized in that a mixture is produced the end: A. 30 to 75 tsp. of a crystalline, isotactic propylene homopolymer with a melt index between 1 and 25 dg / min and B. 25 to 70 Tlen. a rubbery ethylene-propylene polymer with a crystallinity of less than 10% by weight, an ethylene content 2 of more than 58% by weight, a tensile strength of more than 30 kg / cm and a Mooney viscosity (ML Γχ + 4 J 125 ° C) as a measure for the molecular weight, which is at least 30 and at most 90, where C. maximum 15 tie. of the propylene homopolymer and at least as much Divide as by half the numerical value of the melt index of the propylene homopolymer is specified, are replaced by as many polyethylene parts with a density between 0.91 and 0.98 g / cm. 2. The method according to claim 1, characterized in that the maximum Mooney viscosity of the rubber-like ethylene-propylene polymer from the equation ML = 90 - ergiljt, where, m.i. the Represents the melt index of the propylene polymer used. 3. The method according to claim 2, characterized in that the maximum Mooney viscosity results from the equation ML = 90 r - ^ -. 4. The method according to claims 1-3, characterized in that from one of A. 50 to 70 tsp. Propylene homopolymer and B. 30 to 50 parts. Ethylene-propylene polymer assumed existing mixture will. 5. The method according to claims 1-4, characterized in that the minimum Number of propylene homopolymer parts replaced by polyethylene is 3/4 of the numerical value of the melt index of the propylene polymer. 6. The method according to claims 1-5, characterized in that the rubber-like Ethylene-propylene polymer has an ethylene content of at least 61% by weight. 7. The method according to claim 6, characterized in that the rubber-like Ethylene-propylene polymer not more than 77% by weight, preferably not more than. Contains 75 wt .-% and in particular a maximum of 70 wt .-% ethylene. 8. The method according to claims 1-7, characterized in that the rubber-like Ethylene-propylene copolymer has a maximum crystallinity 809848/0787 ORIGINAL INSPECTED 4 wt .-% and in particular of a maximum of 1 wt .-%. 9. The method according to claims 1-8, characterized in that the rubber-like Ethylene-propylene polymer has a tensile strength of more than 50 kg / cm. 10. The method according to claims 1-9, characterized in that the ethylene-propylene polymer contains a polyunsaturated monomer in an amount of not more than 20% by weight and in particular not more than 10% by weight. 11. The method according to claim 10, characterized in that the polyunsaturated Monomers from the group dicyclopentadiene, ethylidene norbornene, 1,4-hexadiene, 1,5-hexadiene and norbornadiene is selected. 12. The method according to claims 1-11, characterized in that the crystalline Propylene homopolymer has a melt index between 1.5 and 20 dg / min and preferably between 5 and 15 dg / min. 13. The method according to claims 1-12, characterized in that the pro · pylene homopolymer has a density between 0.900 and 0.910 g / cm. 14. The method according to claims 1-13, characterized in that the density of the polyethylene is more than 0.94 g / cm. 15. The method according to claims 1-14, characterized in that the The density of the polyethylene is more than 0.96 g / cm. 16. The method according to claims 1-15, characterized in that the polyethylene has a melt index between 0.1 and 35 dg / min and preferably between 1 and 25 dg / min. 17. The method according to claims 1-16, characterized in that the polyethylene Contains a maximum of 0.5% by weight of comonomer. 18. Mixtures prepared by the process described in claims 1-17. 19. Articles, wholly or partially produced from mixtures according to claim 18th 809848/0787 *