DE102017201503A1 - Process for the preparation of a raw material mixture, process for the preparation of a rubber mixture and process for the preparation of a vulcanizate - Google Patents

Abstract

The invention relates to a process for producing a raw material mixture, characterized in that the process comprises at least the following step: extruding one or more plasticizers and vulcanized rubber particles in an extrusion apparatus with an extrusion head to form a raw material mixture. The invention also relates to a process for the preparation of a rubber mixture and to a process for the preparation of a vulcanizate.

Description

The invention relates to a method for producing a raw material mixture and to a method for producing a rubber mixture containing the raw material mixture and to a method for producing a vulcanizate from the rubber or the raw material mixture.

Rubber-containing articles find a variety of applications in various industries of everyday life or in various industries. Both natural and synthetic rubber is produced in a very costly manner in several process steps. One cost, which at the same time also pollutes the environment, is the use of natural raw materials for the production of natural and synthetic rubber. In order to reduce the use of natural raw materials, rubber stocks are often recycled in the production of rubber articles, e.g. Used tires or rubber products that are no longer used. This can also reduce the amount of waste material from rubber-containing old stocks.

So that the rubber-containing old stocks can be reused for the production of a new rubber article, the rubber parts from the old stocks must first be coarsely reduced, then finely ground and then aftertreated. Fine grinding and post-treatment are energy-intensive and therefore undesirable process steps in the production of a new rubber article from rubber-containing old stocks.

There is therefore a need in the industry, particularly in the rubber industry, to simplify the recycling of post-consumer rubber stocks in the manufacture of a new rubber article or to reduce the number of process steps.

• CN 101117022 A offenbart „Manufacturing method of wheel inner tube on the vehicle“ (Abstract). In dem Verfahren werden regeneriertes Gummi, Kautschuk und Weichmacher verwendet.
• DE2049974A1 offenbart ein „Verfahren und [eine] Vorrichtung zur kontinuierlichen Regenerierung von Gummi- und Kunststoffen“ (Bezeichnung). Hierbei werden „mit Weichmachern und Regenerierungsmitteln benetzte Materialien in einem [...] Mehrschneckenapparat“ (siehe Anspruch 1) depolymerisiert.
• US 2012/0184634 A offenbart eine „thermal regeneration method of waste rubber“ (Abstract). Es wird offenbart, dass Partikel und Weichmacher in einem Gewichtsverhältnis von 100:8 bis 100:150 vermischt und erhitzt werden.

Various production methods are known in the prior art in which, among other things, rubber-containing old stocks are used:

• CN 101117022 A discloses "Manufacturing method of wheel inner tube on the vehicle" (abstract). Regenerated rubber, rubber and plasticizers are used in the process.
• DE2049974A1 discloses a "method and apparatus for the continuous regeneration of rubber and plastics" (designation). Here, "wetted with plasticizers and regenerants materials in a [...] multi-screw apparatus" (see claim 1) are depolymerized.
• US 2012/0184634 A discloses a "thermal regeneration method of waste rubber" (abstract). It is disclosed that particles and plasticizers are mixed and heated in a weight ratio of 100: 8 to 100: 150.

The object underlying the invention is to provide a faster or simplified process for the production of tires or technical rubber articles in comparison with methods known from the prior art, in which already vulcanized rubber particles are processed. At the same time, it was an object of the invention to provide a more environmentally friendly process for the production of tires or engineering rubber articles in comparison with methods known in the art.

1. a) Extrudieren eines oder mehrerer Weichmacher und vulkanisierter Kautschukpartikel in einer Extrusionsvorrichtung mit einem Extrusionskopf zu einer Rohmaterialmischung.

This object is achieved according to the invention by a method for producing a raw material mixture, characterized in that the method has at least the following step:

1. a) Extruding one or more plasticizers and vulcanized rubber particles in an extrusion device with an extrusion head to a raw material mixture.

It has surprisingly been found that by extruding vulcanized rubber particles in the presence of one or more plasticizers, a raw material mixture is obtained which can be used without further processing steps to produce a rubber mixture or a ready-mix. Subsequently, the thus prepared rubber or finished mixture can be processed in a known manner to a new rubber article. This eliminates the need for energy-intensive fine grinding and the subsequent treatment of the vulcanized rubber particles. The total number of production steps is therefore reduced by the steps of fine grinding and post-treatment. This saves process costs and in particular energy costs.

The process of the invention can be carried out in various ways and also has the advantage, in comparison to the process steps of the fine grinding and the aftertreatment, that it can be operated continuously. It can therefore be adapted precisely due to this increased variability and due to the continuous production of changing production needs. Thus, further process costs, in particular energy costs, can be saved.

Without wishing to be bound by any scientific theory, it is believed that due to the shearing forces between the rubber particles in the extrusion head, the unvulcanized rubber particles are modified so that the resulting raw material mixture readily and upon addition of further materials to a rubber compound and then to a final mixture can be. Due to the modification results in a particularly good dispersion of the components of the raw material mixture in the resulting rubber mixture and thus also in the final mixture prepared from the rubber mixture.

Plasticizers in the context of the present invention are substances which, when added to a mixture, reduce the viscosity of the resulting mixture compared to before the addition, e.g. MES (mild extraction solvate), RAE (Residual Aromatic Extract), TDAE (treated distillate aromatic extract), Rubber-to-Liquid oils (RTL) and Biomass-to-Liquid oils (BTL).

Vulcanized rubber particles in the context of the present invention are particles which contain vulcanized rubber. In vulcanized rubber, the long-chain rubber molecules are bonded together, in the case of sulfur vulcanization, for example by sulfur bridges.

The above-described method for producing a raw material mixture is preferably used in the rubber industry, more preferably in the tire industry.

Preferred is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that the raw material mixture is suitable for the production of a tire or a technical rubber article or further processed for the production of a tire or a technical rubber article, preferably Manufacturing a tire is processed.

Preferred is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that the vulcanized rubber particles have an average particle size in the range of 0.3 to 30 mm, preferably in the range of 0.425 to 20 mm, more preferably in the range of 0.7 to 2.5 mm. For the determination of the mean particle size see the section "Measuring Methods" in the examples. The determination is preferably carried out with a shaking time of 5 minutes and with sieves having mesh sizes of 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 3 mm , 5 mm, 15 mm, 25 mm and 35 mm (accordingly, according to the measuring method discussed below, d ₁ = 0.1 mm, d ₂ = 0.3 mm, d ₃ = 0.5 mm, etc., to d ₁₀ = 20 mm and d ₁₁ = 30 mm).

• - eine mittlere Partikelgröße im Bereich von 0,3 bis 30 mm aufweisen, wobei einzelne vulkanisierte Kautschukpartikel nicht größer als 500 mm sind, bevorzugt nicht größer als 100 mm,
• - besonders bevorzugt eine mittlere Partikelgröße im Bereich von 0,425 bis 20 mm aufweisen, wobei einzelne vulkanisierte Kautschukpartikel nicht größer als 30 mm sind,
• - ganz besonders bevorzugt eine mittlere Partikelgröße im Bereich von 0,7 bis 2,5 mm, wobei einzelne vulkanisierte Kautschukpartikel nicht größer als 10 mm sind,
• - insbesondere bevorzugt eine mittlere Partikelgröße im Bereich von 0,7 bis 2,5 mm, wobei einzelne vulkanisierte Kautschukpartikel nicht größer als 5 mm sind.

Very particularly preferred is a process as described above (or as described above as preferred), characterized in that the vulcanized rubber particles

• have an average particle size in the range of 0.3 to 30 mm, wherein individual vulcanized rubber particles are not larger than 500 mm, preferably not larger than 100 mm,
• particularly preferably have an average particle size in the range from 0.425 to 20 mm, with individual vulcanized rubber particles not being larger than 30 mm,
• most preferably an average particle size in the range of 0.7 to 2.5 mm, wherein individual vulcanized rubber particles are not larger than 10 mm,
• - Particularly preferred an average particle size in the range of 0.7 to 2.5 mm, wherein individual vulcanized rubber particles are not greater than 5 mm.

• - die vulkanisierten Kautschukpartikel eine mittlere Partikelgröße im Bereich von 0,3 bis 30 mm aufweisen und mindestens 50 Massenprozent, vorzugsweise mindestens 90 Massenprozent, der vulkanisierten Kautschukpartikel eine Partikelgröße im Bereich von 0,01 mm bis 50 mm aufweisen,
• - bevorzugt die vulkanisierten Kautschukpartikel eine mittlere Partikelgröße von 0,425 bis 20 mm und mindestens 50 Massenprozent, vorzugsweise mindestens 90 Massenprozent, der vulkanisierten Kautschukpartikel eine Partikelgröße im Bereich von 0,05 mm bis 30 mm aufweisen,
• - besonders bevorzugt die vulkanisierten Kautschukpartikel eine mittlere Partikelgröße von 0,7 bis 2,5 mm und mindestens 50 Massenprozent, vorzugsweise mindestens 90 Massenprozent, der vulkanisierten Kautschukpartikel eine Partikelgröße im Bereich von 0,1 mm bis 10 mm oder ganz besonders bevorzugt im Bereich von 1 mm bis 6 mm aufweisen.

Very particular preference is also given to a process as described above or as described above as being preferred or described as being particularly preferred in that

• the vulcanized rubber particles have an average particle size in the range from 0.3 to 30 mm and at least 50% by mass, preferably at least 90% by mass, of the vulcanized rubber particles have a particle size in the range from 0.01 mm to 50 mm,
• the vulcanized rubber particles preferably have a mean particle size of from 0.425 to 20 mm and at least 50% by mass, preferably at least 90% by mass, of the vulcanized rubber particles having a particle size in the range from 0.05 mm to 30 mm,
• the vulcanized rubber particles particularly preferably have an average particle size of 0.7 to 2.5 mm and at least 50% by mass, preferably at least 90% by mass, of the vulcanized rubber particles having a particle size in the range from 0.1 mm to 10 mm or very particularly preferably in the range from 1 mm to 6 mm.

In the present invention, the particle size of a single vulcanized rubber particle is preferably the distance between the two most distant points of the one vulcanized rubber particle which can be measured with a light microscope of the prior art.

An advantage of the aspect of the invention described above is that when using vulcanized rubber particles having a very large particle size as described above, the process step of the fine grinding can be omitted and thus the process of recycling already used rubber particles can be simplified.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that the vulcanized rubber particles are made of vulcanized rubber waste, preferably from old conveyor belts and / or vulcanized rubber waste from tire production, more preferably from scrap tires , Hoses, conveyor belts, hose bands and / or heating and building casings.

Rim tapes, conveyor belts, drive belts, drive chains, handles, mats, floor coverings, seals or damping units of any kind can also be used as coarse comminution as vulcanized rubber particles in a method according to the invention.

The advantage of the above-described aspect of the present invention is that the rubber wastes described above are suitable for one of the above-described processes for producing a raw material mixture and, at the same time, are more widely available as unvulcanized rubber products on the market. The use of a large selection of rubbery old stocks also has the advantage that a large proportion of old stocks can be recycled. However, old conveyor belts and vulcanized rubber waste from tire production are better suited for processing in one of the above-described processes for producing a raw material mixture than other rubber waste. Even better are used tire remnants, hoses, conveyor belts, hose bands and heating and building casings.

For all of the materials described above, only a rough comminution of rubber waste has to be carried out, thus eliminating the process step of fine grinding and aftertreatment.

Preferred is a process for preparing a raw material mixture as described above (or as described above as preferred), characterized in that the vulcanized rubber particles contain at least one rubber selected from the group consisting of butadiene rubber (BR), styrene-butadiene rubber ( SBR), natural polyisoprene (NR), butyl rubber (IIR) and synthetic polyisoprene (IR).

The advantage of the above-described aspect of the present invention is that the rubbers described above are suitable for one of the above-described processes for producing a raw material mixture and at the same time are available on the market to a greater extent than other rubbers.

The rubbers described above, in particular the diene rubbers described above, are used in the manufacture of technical rubber articles, such as belts, straps and hoses, and / or shoe soles.

The rubber compound is particularly suitable for vehicle tires, where it can be used in principle in any component, such as in particular the tread, the side wall, the horn profile, as well as in other so-called body components.

Particularly preferred is a method as described above preferably characterized in that the vulcanized rubber particles contain at least one rubber selected from the group consisting of butadiene rubber (BR), styrene-butadiene rubber (SBR), natural polyisoprene (NR) and synthetic Polyisoprene (IR).

In some cases, it is desirable that different types of rubbers be mixed together or that certain types of rubber be dispensed with in order to achieve certain technical effects. In other cases, however, it may also be helpful to use only one type of rubber. The latter applies z. For butyl rubber, as in blends containing butyl rubber and another type of rubber, undesirable separation of the butyl rubber from the other rubbers may occur under certain circumstances. This would make co-vulcanization of the separated butyl rubber in the blend with the other type of rubber problematic.

Preferred is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that the raw material mixture has a Mooney viscosity at 100 ° C in a range of 10 to 200 Mooney units, preferably 20 to 95 Mooney units, more preferably in a range of 35 to 70 Mooney units, most preferably in a range of 35 to 51 Mooney units.

An advantage of the above-described aspect of the present invention is that raw material mixtures having viscosities in the ranges described above are particularly suitable for further processing into a rubber mixture, since such a raw material mixture can be mixed particularly well with further ingredients to form a rubber mixture, in particular mixed very homogeneously can. By means of a small number of simple preliminary tests, suitable production parameters can be found so that the resulting raw material mixture has a Mooney viscosity in the ranges described above.

Preferred is a process for preparing a raw material mixture as described above (or as described above as preferred) characterized in that the vulcanized rubber particles and the one or more plasticizers are premixed prior to extrusion to form the raw material mixture.

The above-described aspect of the present invention has the advantage that mixing results in a premix to a still more processable raw material mixture, i. that such a raw material mixture can be mixed particularly well with other ingredients to a rubber mixture.

• - Einschneckenextruder
• - Mehrschneckenextruder und
• - Fütter-Einheit in Kombination mit einer Zahnradpumpe.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that the extrusion device is selected from the group consisting of:

• - Single screw extruder
• - Multi-screw extruder and
• - Feeding unit in combination with a gear pump.

Particularly preferred in a process as described above is the use of a ring extruder or a planetary roller extruder as a multi-screw extruder. However, the use of a twin-screw extruder is very particularly preferred.

Preferred is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that the extrusion device has an inner extruder diameter d _inner in the range of 20 mm to 100 mm, preferably in the range of 30 mm to 60 mm, a length L in the range from 20 to 100 times the inner diameter d extruder _inner, preferably _within up to 60 times the inner diameter d extruder in the range of the 40, and a ratio V from inner to outer extruder diameter in the range of 1.2 to 2, preferably with a ratio V in the range of 1.4 to 1.7.

The above-described aspect of the present invention has the advantage that the one or more plasticizers with the vulcanized rubber particles can be extruded to a raw material mixture in a particularly energy-saving and process-technically simple manner.

In the context of the present invention, a feeding unit is a device which serves to feed one, two or more substances to a gear pump.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that the premix is prepared in a separate pre-mixer, for example in a dispersion stirrer, internal mixer or a fluid mixer, preferably in an internal mixer.

The premixers described above are suitable in a particularly advantageous manner for producing raw material mixtures according to the invention.

For example, in a process for producing a raw material mixture of the present invention as described above (or as described above), CO ₂ in the supercritical state may be used in addition to the plasticizers and the vulcanized rubber particles. The CO ₂ in the supercritical state can act as a solvent.

• MES (mild extraction solvate), RAE (Residual Aromatic Extract), TDAE (treated distillate aromatic extract), Rubber-to-Liquid-Ölen (RTL) und
• Biomass-to-Liquid-Ölen (BTL), Rapsöl, Faktissen und Flüssig-Polymeren, wobei der oder einer der mehreren Weichmacher bevorzugt ausgewählt ist aus der Gruppe bestehend aus: TDAE, RAE, MES und Rapsöl. Besonders bevorzugt ist die Verwendung von TDAE als Weichmacher.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that the or at least one of the plurality of plasticizers is selected from the group consisting of:

• MES (mild extraction solvate), RAE (Residual Aromatic Extract), TDAE (treated distillate aromatic extract), Rubber-to-Liquid oils (RTL) and
• Biomass-to-liquid oils (BTL), rapeseed oil, batches and liquid polymers, wherein the or one of the plurality of plasticizers is preferably selected from the group consisting of: TDAE, RAE, MES and rapeseed oil. Particularly preferred is the use of TDAE as a plasticizer.

The plasticizers described above are particularly well suited to extrude vulcanized rubber particles, in particular those vulcanized rubber particles, which consist of rubber-containing old stocks, to a raw material mixture according to the invention. The advantage of the above-described aspect lies in a particularly advantageous interaction of the above-described plasticizers, in particular of the plasticizers described above as preferred, with vulcanized rubber particles.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that in the extrusion head of the extrusion device is a temperature in the range of 70 ° C to 250 ° C, preferably in the range of 80 ° C. to 175 ° C, more preferably in the range of 90 ° C to 115 ° C.

The advantage of the above-described aspect of the present invention is that the above-mentioned temperatures result in particularly good processible raw material mixtures.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that in the extrusion head of the extrusion device, a pressure in the range of 10 bar to 500 bar, preferably in the range of 10 bar to 300 bar , more preferably in the range of 25 bar to 220 bar.

The advantage of the above-described aspect of the present invention is that particularly good processable raw material mixtures result in the aforementioned pressure ranges.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that the extrusion device is operated at a flow rate in the range of 5 kg / h to 2500 kg / h, preferably in the range of 50 kg / h to 1000 kg / h, more preferably in the range of 200 kg / h to 600 kg / h, based on the total mass of the one or more plasticizers and the vulcanized rubber particles.

The advantage of the above-described aspect of the present invention is that setting the above-mentioned throughput results in particularly well processable raw material mixtures.

Preferred is a process for producing a raw material mixture as described above (or as described above as preferred), characterized in that in the raw material mixture the ratio of the total mass of vulcanized rubber particles to the total mass of plasticizers is in the range of 500: 1 to 1: 1 , preferably in the range from 250: 1 to 3: 1, more preferably in the range from 25: 1 to 5: 1.

The advantage of the above-described aspect of the present invention is that the adjustment of the above-described ratios of the total mass of vulcanized rubber particles to the total mass of plasticizers results in a particularly easily processible raw material mixture.

• - in der Rohmaterialmischung das Verhältnis der Gesamtmasse an vulkanisierten Kautschukpartikeln zu der Gesamtmasse an Weichmachern im Bereich von 25:1 bis 5:1 liegt,
• - die Rohmaterialmischung eine Mooney-Viskosität bei 100°C in einem Bereich von 35 bis 70 Mooney-Einheiten aufweist,
• - der Weichmacher oder einer der Weichmacher TDAE ist,
• - die Extrusionsvorrichtung ein Zweischnecken-Extruder (bevorzugt ein Zweischnecken-Extruder wie im nachfolgenden Absatz beschrieben),
• - in dem Extrusionskopf des Zweischnecken-Extruders eine Temperatur im Bereich von 130 °C bis 140 °C vorliegt,
• - in dem Extrusionskopf des Zweischnecken-Extruders ein Druck im Bereich von 150 bar bis 170 bar vorliegt und
• - der Zweischnecken-Extruder mit einem Durchsatz im Bereich von 30 kg/h bis 50 kg/h betrieben wird.

Very particularly preferred is a process for preparing a raw material mixture as described above (or as described above as preferred), characterized in that

• in the raw material mixture, the ratio of the total mass of vulcanized rubber particles to the total mass of plasticizers is in the range of 25: 1 to 5: 1,
• the raw material mixture has a Mooney viscosity at 100 ° C. in a range from 35 to 70 Mooney units,
• the plasticizer or one of the plasticisers is TDAE,
• the extrusion device is a twin-screw extruder (preferably a twin-screw extruder as described in the following paragraph),
• in the extrusion head of the twin-screw extruder a temperature in the range of 130 ° C to 140 ° C,
• - In the extrusion head of the twin-screw extruder, a pressure in the range of 150 bar to 170 bar is present and
• - The twin-screw extruder is operated at a throughput in the range of 30 kg / h to 50 kg / h.

• - die Extrusionsvorrichtung ein Zweischnecken-Extruder mit einem inneren Extruderdurchmesser d_inner von 40 mm, einer Länge L von 56-mal dem inneren Extruderdurchmesser d_inner und einem Verhältnis V von innerem zu äußerem Extruderdurchmesser von 1,56 ist, d.h. d_inner= 40 mm, L = 2240 mm und V = d_inner / d_outer = 1,56,
• - in dem Extrusionskopf des Zweischnecken-Extruders eine Temperatur im Bereich von 130 °C bis 140 °C vorliegt,
• - in dem Extrusionskopf des Zweischnecken-Extruders ein Druck im Bereich von 150 bar bis 170 bar ist und
• - der Zweischnecken-Extruder mit einem Durchsatz im Bereich von 30 kg/h bis 50 kg/h betrieben wird.

A possible embodiment of a method according to the invention for producing a raw material mixture is a method as described above (or as described above as preferred), characterized in that

• - the extrusion device comprises a twin-screw extruder having an inner extruder diameter d is _within 40 mm, a length L of 56 times the inner extruder diameter d _intra and a ratio V of inner to outer extruder diameter of 1.56, ie d _intra = 40 mm , L = 2240 mm and V = d _inner / d _outer = 1.56,
• in the extrusion head of the twin-screw extruder a temperature in the range of 130 ° C to 140 ° C,
• - In the extrusion head of the twin-screw extruder, a pressure in the range of 150 bar to 170 bar and
• - The twin-screw extruder is operated at a throughput in the range of 30 kg / h to 50 kg / h.

The above-described specific embodiment of the present invention is an embodiment of how the present invention can be carried out. It is not intended to limit the scope of the present invention, but is an aid to the practice of the subject matter of the present invention.

• - die Extrusionsvorrichtung ein Planetwalzen-Extruder mit einem inneren Extruderdurchmesser d_inner von 150 mm ist,
• - in dem Extrusionskopf des Planetwalzen-Extruders eine Temperatur im Bereich von 100 °C bis 110 °C vorliegt und
• - der Planetwalzen-Extruder mit einem Durchsatz im Bereich von 200 kg/h bis 250 kg/h betrieben wird.

Another possible embodiment of a method according to the invention is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that

• - the extrusion device is a planetary roller extruder with an internal extruder diameter d _inner of 150 mm,
• - In the extrusion head of the planetary roller extruder a temperature in the range of 100 ° C to 110 ° C is present and
• - The planetary roller extruder is operated at a throughput in the range of 200 kg / h to 250 kg / h.

The above-described specific embodiment of the present invention is an embodiment of how the present invention can be carried out. It is not intended to limit the scope of the present invention, but is an aid to the practice of the subject matter of the present invention.

• - die Extrusionsvorrichtung ein Ring-Extruder mit einem inneren Extruderdurchmesser d_inner von 30 mm, einer Länge L von 55-mal dem inneren Extruderdurchmesser d_inner und einem Verhältnis V von innerem zu äußerem Extruderdurchmesser von 1,74 ist, d.h. d_inner= 30 mm, L = 1650 mm und V = d_inner / d_outer = 1,74,
• - in dem Extrusionskopf des Ring-Extruders eine Temperatur im Bereich von 140 °C bis 150 °C vorliegt,
• - in dem Extrusionskopf des Ring-Extruders ein Druck im Bereich von 150 bar bis 170 bar vorliegt und
• - der Ring-Extruder mit einem Durchsatz im Bereich von 5 kg/h bis 60 kg/h betrieben wird.

A further possible embodiment of a method according to the invention is a method for producing a raw material mixture as described above (or as described above as preferred), characterized in that

• - the extrusion device is a ring extruder having an internal extruder diameter d is _within 30 mm, a length L of 55 times the inner extruder diameter d _intra and a ratio V of inner to outer extruder diameter of 1.74, ie d _intra = 30 mm , L = 1650 mm and V = d _inner / d _outer = 1.74,
• in the extrusion head of the ring extruder a temperature in the range of 140 ° C to 150 ° C,
• - In the extrusion head of the ring extruder, a pressure in the range of 150 bar to 170 bar is present and
• - The ring extruder is operated at a throughput in the range of 5 kg / h to 60 kg / h.

The above-described specific embodiment of the present invention is an embodiment of how the present invention can be carried out. It is not intended to limit the scope of the present invention, but is an aid to the practice of the subject matter of the present invention.

The three possible embodiments described above show that the present invention can be implemented in many different ways. Depending on the realized design, individual parameters of the subject matter of the present invention are to be adapted, if necessary to be determined by a small number of preliminary tests.

The invention also relates to a raw material mixture for producing a vulcanizate, prepared or preparable by a process for preparing a raw material mixture, as described above or as described above as being preferred or particularly preferred.

The above-described advantageous aspects of a method according to the invention for producing a raw material mixture also apply to all aspects of a raw material mixture according to the invention for producing a vulcanizate. A raw material mixture according to the invention as described above for producing a vulcanizate differs from other raw material mixtures known in the art, in particular in that a raw material mixture according to the invention for the preparation of a vulcanizate has the above-defined Mooney viscosity and, as in a method according to the invention for producing a vulcanizate Vulcanisats explained, can be vulcanized without the addition of unvulcanized rubber ingredients.

The invention also relates to the use of a raw material mixture as described above for the preparation of a rubber mixture (as described below in a process according to the invention), for the preparation of a ready-mix (as described below) or for the preparation of a vulcanizate (as described below in a process according to the invention).

A raw material mixture according to the invention as described above is preferably characterized in that no vulcanized rubber particles having a particle size of greater than 30 mm, preferably greater than 10 mm, particularly preferably greater than 1 mm, very particularly preferably greater than 0.1 mm, in the raw material mixture, in particular, very particularly preferably greater than 0.01 mm.

• b) Herstellen einer Kautschukmischung durch Mischen der Rohmaterialmischung mit unvulkanisierten Kautschukbestandteilen und optional weiteren Ingredienzien.

The invention also relates to a process for the preparation of a rubber mixture, characterized in that the process comprises the step (s) of one of the processes defined above and additionally comprises at least the following step:

• b) preparing a rubber mixture by mixing the raw material mixture with unvulcanized rubber ingredients and optionally further ingredients.

1. a) Extrudieren eines oder mehrerer Weichmacher und vulkanisierter Kautschukpartikel in einer Extrusionsvorrichtung mit einem Extrusionskopf zu einer Rohmaterialmischung und
2. b) Herstellen einer Kautschukmischung durch Mischen der Rohmaterialmischung mit unvulkanisierten Kautschukbestandteilen und optional weiteren Ingredienzien.

The process for producing a rubber mixture therefore comprises at least the following steps:

1. a) extruding one or more plasticizers and vulcanized rubber particles in an extrusion device with an extrusion head into a raw material mixture and
2. b) preparing a rubber mixture by mixing the raw material mixture with unvulcanized rubber ingredients and optionally further ingredients.

The above-described advantageous aspects of a method according to the invention for producing a raw material mixture also apply to all aspects of a method for producing a rubber mixture described below and the advantageous aspects of inventive methods for producing a rubber mixture discussed below apply correspondingly to all aspects of a method according to the invention for producing a raw material mixture.

Surprisingly, it has been found that a raw material mixture resulting from one of the processes described above can be mixed particularly well with unvulcanized rubber constituents or other ingredients. This results in particularly homogeneous mixed rubber compounds, which can be further processed without much additional effort.

In the context of the present invention, a rubber mixture is preferably defined as containing unvulcanized rubber molecules, i. H. those rubber molecules that have not been bonded together by additional crosslinking reactions in a vulcanization.

• - weiteren Weichmachern, z. B. TDAE,
• - wenigstens einem Füllstoff, bevorzugt Ruß (z.B. N 550) und/oder Silica,
• - Harzen,
• - Alterungsschutzmitteln,
• - Ozonschutzwachsen,
• - Silane,
• - Aktivatoren und
• - Verarbeitungshilfsmittel.

A process for the preparation of a rubber mixture as described above is preferably characterized in that the rubber mixture additionally comprises at least one, two, three, four, preferably all further ingredients selected from the group consisting of:

• - Other plasticizers, z. Eg TDAE,
• at least one filler, preferably carbon black (eg N 550) and / or silica,
• - resins,
• - anti-aging agents,
• - Ozone protection growing,
• - silanes,
• - Activators and
• - processing aids.

If further plasticizers are used as further ingredients in the rubber mixture, these other plasticizers may either be different, similar or the same plasticizers which have already been used in the raw material mixture. Preferred further plasticizers than further ingredients in the rubber mixture are the plasticizers already described above for the raw material mixture.

Preference is given to the use of resins in which the polymers can form cross-links with each other and thereby contribute to the curing of the mixture. These include in particular polymers which have a double bond between two C atoms or a double bond between a C and an O atom, such as. As polybutadienes, polyisoprenes and polyacrylates.

Anti-aging agents are, for example, 6PPD (CAS No .: 793-24-8) and TMQ (CAS No .: 26780-96-1).

Activators are, for example, zinc oxide and stearic acid. Processing aids are, for example, zinc soaps.

Silane coupling agents are also referred to in the context of the present invention as "silanes" and can be used as further ingredients as described above.

Here, one or more different silane coupling agents can be used in combination with each other. The respective finished mixture, which results from the rubber mixture, can thus contain a mixture of different silanes. The silane coupling agents can react with the surface of the vulcanized rubber particles or other polar groups.

As silane coupling agents, it is possible to use all silane coupling agents known in the prior art for use in finished mixtures. Such known from the prior art coupling agents are, for example, bifunctional organosilanes having on the silicon atom at least one alkoxy, cycloalkoxy or phenoxy group as a leaving group and have as other functionality a group that can optionally undergo a chemical reaction with the double bonds of the polymer. In the latter group may be z. For example, they may be the following chemical groups: -SCN, -SH, -NH ₂ or -S _x - (where x = 2 to 8).

• 3-Mercaptopropyltriethoxysilan,
• 3-Thiocyanato-propyltrimethoxysilan und
• 3,3'-Bis(triethoxysilylpropyl)polysulfide mit 2 bis 8 Schwefelatomen,

besonders bevorzugt 3,3'-Bis(triethoxysilylpropyl)tetrasulfid (TESPT), das entsprechende Disulfid (TESPD) oder auch Gemische aus den Sulfiden mit 2 bis 8
Schwefelatomen mit unterschiedlichen Gehalten an den verschiedenen Sulfiden.Preferably, one of the following silane coupling agents is used as a further ingredient:

• 3-mercaptopropyltriethoxysilane,
• 3-thiocyanato-propyltrimethoxysilane and
• 3,3'-bis (triethoxysilylpropyl) polysulfides having 2 to 8 sulfur atoms,

particularly preferred 3,3'-bis (triethoxysilylpropyl) tetrasulfide (TESPT), the corresponding disulfide (TESPD) or mixtures of the sulfides with 2 to 8
Sulfur atoms with different contents of the different sulfides.

For example, TESPT can also be added as a mixture with carbon black (trade name X50S® from Evonik).

Preferred is a process for producing a rubber mixture as described above (or as described above as preferred), characterized in that in the rubber mixture the ratio of the total mass of unvulcanized rubber components to the total mass of plasticizers in the range of 0.01: 1 to 1000: 1, preferably in the range of 0.1: 1 to 100: 1, more preferably in the range of 1: 1 to 10: 1.

An advantage of the above-described aspect of the present invention is that rubber compounds having the above-described ratios can be processed particularly well into rubber articles, in particular tires.

Preferred is a process for producing a rubber mixture as described above (or as described above as preferred), characterized in that
in the rubber mixture, the ratio of the total mass of fillers to the total mass of plasticizers is in the range from 250: 1 to 20: 1, preferably in the range from 200: 1 to 30: 1, particularly preferably in the range from 150: 1 to 40: 1,
and or
in the rubber mixture, the ratio of the total mass of fillers to the total mass of unvulcanized rubber components is in the range from 250: 1 to 1:10, preferably in the range from 100: 1 to 1: 5, particularly preferably in the range from 3: 1 to 1 : 2nd

An advantage of the above-described aspect of the present invention is that rubber compounds having the above-described ratios can be processed particularly well into rubber articles, in particular tires.

Preferred is a process for producing a rubber mixture as described above (or as described above as preferred), characterized in that the total mass of unvulcanized rubber components in the rubber mixture is in the range of 0.1 to 50 wt .-%, preferably in the range of 5 to 30 wt .-%, particularly preferably in the range of 10 to 20 wt .-%, each based on the total mass of the rubber mixture.

An advantage of the above-described aspect of the present invention is that rubber compounds having the above-described total amounts of unvulcanized rubber components can be mixed very well with a raw material mixture prepared as described above, in particular homogeneously mixed.

Preferred is a process for producing a rubber composition as described above (or as described above as preferred), characterized in that the unvulcanized rubber components comprise at least one rubber selected from the group consisting of butadiene rubber (BR), styrene-butadiene Rubber (SBR), natural polyisoprene (NR), butyl rubber (IIR) and synthetic polyisoprene (IR).

• - den oder die Schritte
  • wie vorstehend in einem Verfahren zur Herstellung einer Rohmaterialmischung beschrieben (bzw. wie vorstehend in einem bevorzugten Verfahren zur Herstellung einer Rohmaterialmischung beschrieben) oder
  • wie vorstehend in einem Verfahren zur Herstellung einer Kautschukmischung wie vorstehend beschrieben (bzw. wie vorstehend in einem bevorzugten Verfahren zur Herstellung einer Kautschukmischung beschrieben)
  aufweist

und zusätzlich

• - die folgenden Schritte aufweist:
  • c) Mischen der Rohmaterialmischung oder der Kautschukmischung mit Vulkanisationsmitteln zu einer Fertigmischung und
  • d) Vulkanisieren der in Schritt c) hergestellten Fertigmischung, sodass ein Vulkanisat resultiert.

The invention also relates to a process for the preparation of a vulcanizate, characterized in that the process

• - the or the steps
  • as described above in a process for producing a raw material mixture (or as described above in a preferred process for preparing a raw material mixture) or
  • as described above in a process for producing a rubber composition as described above (or as described above in a preferred process for preparing a rubber composition)
  having

and additionally

• - has the following steps:
  • c) mixing the raw material mixture or the rubber mixture with vulcanizing agents into a finished mixture and
  • d) vulcanizing the finished mixture prepared in step c) so that a vulcanizate results.

• a) Extrudieren eines oder mehrerer Weichmacher und vulkanisierter Kautschukpartikel in einer Extrusionsvorrichtung mit einem Extrusionskopf zu einer Rohmaterialmischung,
• c) Mischen der Rohmaterialmischung mit Vulkanisationsmitteln zu einer
• Fertigmischung und
• d) Vulkanisieren der in Schritt c) hergestellten Fertigmischung, sodass ein Vulkanisat resultiert

oder

1. a) Extrudieren eines oder mehrerer Weichmacher und vulkanisierter Kautschukpartikel in einer Extrusionsvorrichtung mit einem Extrusionskopf zu einer Rohmaterialmischung,
2. b) Herstellen einer Kautschukmischung durch Mischen der Rohmaterialmischung mit unvulkanisierten Kautschukbestandteilen und optional weiteren Ingredienzien,
3. c) Mischen der Kautschukmischung mit Vulkanisationsmitteln zu einer Fertigmischung und
4. d) Vulkanisieren der in Schritt c) hergestellten Fertigmischung, sodass ein Vulkanisat resultiert.

The process for producing a vulcanizate therefore comprises at least the following steps:

• a) extruding one or more plasticizers and vulcanized rubber particles in an extrusion device with an extrusion head into a raw material mixture,
• c) mixing the raw material mixture with vulcanizing agents to one
• Ready mix and
• d) vulcanizing the finished mixture prepared in step c) so that a vulcanizate results

or

1. a) extruding one or more plasticizers and vulcanized rubber particles in an extrusion device with an extrusion head into a raw material mixture,
2. b) preparing a rubber mixture by mixing the raw material mixture with unvulcanized rubber components and optionally further ingredients,
3. c) mixing the rubber mixture with vulcanizing agents to a finished mixture and
4. d) vulcanizing the finished mixture prepared in step c) so that a vulcanizate results.

The advantageous aspects of a process according to the invention for producing a raw material mixture or for producing a rubber mixture described above also apply to all aspects of a process described below for the preparation of a vulcanizate or for all aspects of a ready-mixed mixture described below and the advantageous aspects discussed below of inventive methods for producing a vulcanizate or advantageous aspects of a finished mixture described below apply correspondingly to all aspects of a process according to the invention for producing a raw material mixture or for producing a rubber mixture.

If, in step c) of a process described above, a raw material mixture is mixed to form a finished mixture, step b) is omitted.

The step b) can be mixed in a first mixing device and the step c) in a second mixing device. A first or a second mixing device may be a dispersion stirrer, an internal mixer or a fluid mixer, preferably an internal mixer. Preferably, however, step b) and c) is carried out in a single mixing device, preferably an internal mixer.

The vulcanizate is preferably a technical rubber article or a tire component, particularly preferably a part of a hose, a conveyor belt, a hose band or a heating or construction blade or a tire component, very particularly preferably a tire component, in particular very particularly a tread of a tire.

In the context of the present invention, it may be expedient to carry out further method steps before, between or after the above-described steps a), b) and c).

• - Schwefel,
• - Schwefelspendern,
• - Vulkanisationsbeschleunigern und
• - Silanen.

In the case that a raw material mixture according to the invention is mixed with vulcanizing agents in step c), such a process according to the invention as described above (or as described above as preferred) is preferred, wherein at least one vulcanizing agent is selected from the group consisting of:

• - sulfur,
• - sulfur donors,
• - Vulcanization accelerators and
• - silanes.

Preferably, a raw material mixture to be vulcanized additionally contains one or more resins, anti-aging agents.

The use of resins, sulfur donors, sulfur and silanes, preferably silanes as described above for the preparation of a rubber mixture, in a raw material mixture described above has the advantage that a finished mixture is produced directly from the raw material mixture. The resulting ready mix can thus be directly, i. without the addition of unvulcanized rubber ingredients. This additionally reduces the number of necessary process steps. Particularly preferably, a raw material mixture comprising liquid polymers is mixed with one or all of the vulcanizing agents described above, since such a mixture can be vulcanized particularly well. Even more preferred is the use of resins in which the polymers can form cross-links with each other and thereby contribute to the curing of the mixture. These include in particular polymers which have a double bond between two C atoms or a C and an O atom, such as. As polybutadienes, polyisoprenes and polyacrylates.

• 3-Mercaptopropyltriethoxysilan,
• 3-Thiocyanato-propyltrimethoxysilan und
• 3,3'-Bis(triethoxysilylpropyl)polysulfide mit 2 bis 8 Schwefelatomen.

It is also preferable to add resins, vulcanization accelerators and silanes to a raw material mixture (without the addition of sulfur as a vulcanizing agent), wherein at least one silane is selected from the group consisting of:

• 3-mercaptopropyltriethoxysilane,
• 3-thiocyanato-propyltrimethoxysilane and
• 3,3'-bis (triethoxysilylpropyl) polysulfides having 2 to 8 sulfur atoms.

A particularly preferred silane in this context is 3,3'-bis (triethoxysilylpropyl) tetrasulfide (TESPT), the corresponding disulfide (TESPD) or mixtures of the sulfides having 2 to 8 sulfur atoms with different contents of the various sulfides.

For example, TESPT can also be added as a mixture with carbon black (trade name X50S® from Evonik). The silanes described above have the advantage that in their use can be dispensed with the addition of sulfur as a vulcanizing agent, since the silanes include functional group with sulfur atoms.

Preference is given to using a silane mixture which comprises 40 to 100% by weight of disulfides, particularly preferably 55 to 85% by weight of disulfides and very particularly preferably 60 to 80% by weight of disulfides. Such a mixture is available, for example, under the trade name Si 266® Evonik, which, for example, in the DE 102006004062 A1 is described.

Preferably, a process for producing a vulcanizate as described above is characterized in that the final mixture has a Mooney viscosity in a range of 30 to 150 Mooney units, preferably in a range of 40 to 100 Mooney units, more preferably in one range from 45 to 70 Mooney units, most preferably in a range of 45 to 54 Mooney units.

An advantage of the above-described aspect of the present invention is that finished blends having the Mooney viscosities described above can be processed particularly well in a vulcanization process and therefore also lead to vulcanizates having particularly advantageous properties.

The vulcanization is preferably carried out in the presence of vulcanizing agent, e.g. Silanes, sulfur and / or sulfur donors performed, with some sulfur donors can act as a vulcanization accelerator at the same time. Sulfur or sulfur donors are added in the last mixing step in the amounts customary by the person skilled in the art (0.4 to 8 phr, sulfur, preferably in amounts of 0.4 to 4 phr) of the rubber mixture. The vulcanization can also be carried out in the presence of very small amounts of sulfur in combination with sulfur-donating substances.

The vulcanization accelerators may be selected, for example, from the following groups of accelerators: thiazole accelerators such as. B. 2-mercaptobenzothiazole, sulfenamide accelerators such as. B. benzothiazyl-2-cyclohexylsulfenamide (CBS) or N-tert-butyl-2-benzothiazylsulfenamide (TBBS), guanidine accelerators such as. N, N'-diphenylguanidine (DPG), dithiocarbamate accelerators such as. As zinc dibenzyldithiocarbamate, disulfides, thiophosphates. The accelerators can also be used in combination with each other, which can result in synergistic effects.

In some cases, it is also advantageous to use vulcanization retarders to achieve certain beneficial effects.

The invention will now be explained in more detail with reference to the following examples.

Abbreviations:

• Comp Exp. = Comparative experiment (not according to the invention)
• Exp. = Experiment (according to the invention)

definitions:

The unit "phr" is defined by standard on the rubber content of the mixture to be prepared. The mass fractions of all rubber components are normalized to 100 and the mass fractions of all other constituents are defined by reference to the 100 parts by mass of rubber. In the context of the present invention, only the unvulcanized rubber constituents are used to define the unit "phr". The rubber content of the rubber particles from the raw material mixture is not considered in the context of the present invention in determining the 100 parts of rubber (100 phr).

Measurement Methods:

Mooney viscosity

The results were determined according to the method ASTM D1646 at 100 ° C using a Mooney viscometer in the ML1 + 3 mode. The rotation speed of the stirrer was 2 rpm. The results are given in Mooney units (M.U.).

Determination of mean particle size

wobei

• - d_i der arithmetische Mittelwert der beiden Grenzen der Siebfraktion i ist (d.h. die Mitte zwischen der vorgesehenen maximalen und der vorgesehen minimalen Partikelgröße der Siebfraktion, z. B. ist d₁ = 0,1 mm, wenn die erste Siebfraktion für Partikel mit einer Partikelgröße von 0,0 mm bis 0,2 mm vorgesehen ist und d₂ = 0,3 mm, wenn die zweite Siebfraktion für Partikel mit einer Partikelgröße von 0,2 mm bis 0,4 mm vorgesehen ist, usw.) und
• - µ_i die Massenfraktion der jeweiligen Siebfraktion i ist, wobei die Summe sämtlicher Massenfraktionen auf 1 normiert ist.

The mean particle size is determined by sieving according to DIN EN ISO 4610: 2002-04 determined and determined by means of the measured particle size distribution of the vulcanized rubber particles. The shape of the vulcanized rubber particles can be spherical, flat or oblong after the coarse comminution. The average particle size d _m is calculated mathematically using the determined particle size distribution according to the following mathematical formula: $$d_m={\displaystyle \underset{i=0}{\overset{N}{\Sigma }}{d}_i\cdot {\mathrm{\mu }}_i}$$

in which

• d _{i is} the arithmetic mean of the two boundaries of the sieve fraction i (ie the middle between the intended maximum and the provided minimum particle size of the sieve fraction, eg d ₁ = 0.1 mm if the first sieve fraction for particles with a Particle size of 0.0 mm to 0.2 mm is provided and d ₂ = 0.3 mm, if the second sieve fraction is intended for particles with a particle size of 0.2 mm to 0.4 mm, etc.) and
• - μ _{i is} the mass fraction of the respective sieve fraction i, wherein the sum of all mass fractions is normalized to 1.

Shore A hardness

The results were determined based on the DIN ISO 7619-1 method using a durometer at room temperature and at 70 ° C. The results are given in the unit Shore A (short: Sh A).

tensile strenght

The results were determined on the basis of the DIN 53504 method at room temperature.

elongation

The results were determined on the basis of the DIN 53504 method at room temperature

"Fatigue-to-failure" test ("Monsanto fatigue test")

The results were determined on the basis of the method ASTM D4482 at 106% elongation and room temperature. The results are given in units of kilo cycles (in short: kC).

Production of various raw material mixtures

For example 1 (comparative experiment V1): non-inventive raw material mixture (here: regenerate 1)

• - Zerkleinern des schwefelvernetzten Gummivulkanisates mittels einem kryogenen Mahlverfahren (Stiftmühle) zu einem Granulat mit der Partikelgröße 0,001 bis 0,5 mm,
• - Vorlegen von 90,7 Gew.-% des zerkleinerten zu regenerierenden schwefelvernetzten Gummivulkanisates in einem Innenmischer
• - Erwärmen des zerkleinerten zu regenerierenden schwefelvernetzten Gummivulkanisates auf 60 °C,
• - Zugabe von 2 Gew.-% Ruß (N121),
• - Zugabe von 5,5 Gew.-% Regenerierungsmittel (Bis(triethoxysilyl)propyltetrasulfan (TESPT)),
• - Zugabe von 2 Gew.-% TDAE-Ö1 (TDAE = treated aromatic extract),
• - Durchmischen der genannten Bestandteile zu einer Mischung für eine Dauer von 20 Minuten bei einer Temperatur von 100 °C und
• - Abkühlen der entstandenen Mischung zu einer resultierenden Rohmaterialmischung (hier „Regenerat 1“ genannt).

The preparation of the raw material mixture for comparison experiment V1 not according to the invention was carried out in the following order:

• - crushing the sulfur-vulcanized rubber vulcanizate by means of a cryogenic grinding process (pin mill) into a granulate having a particle size of 0.001 to 0.5 mm,
• - Introducing 90.7 wt .-% of crushed to be regenerated sulfur vulcanized rubber vulcanizate in an internal mixer
• - Heating the shredded sulfur vulcanized rubber vulcanizate to be regenerated to 60 ° C,
• Addition of 2% by weight of carbon black (N121),
• Addition of 5.5% by weight of regenerant (bis (triethoxysilyl) propyl tetrasulfane (TESPT)),
• Addition of 2% by weight of TDAE-oil (TDAE = treated aromatic extract),
• Mixing the said ingredients into a mixture for a period of 20 minutes at a temperature of 100 ° C and
• - Cooling of the resulting mixture to a resulting raw material mixture (here called "Regenerat 1").

Example 2 (Comparative experiment V2): Non-inventive raw material mixture (here: Regenerate 2)

The preparation of the raw material mixture according to the invention for comparative experiment V2 (here called "regenerate 2") was carried out analogously to the above-described preparation of regenerate 1, except that instead of a "sulfur-vulcanized rubber vulcanizate" a commercially available mixture of regenerated rubber materials (product name: Ecorr Reclaim Truck Tire, manufacturer : Rubber Resources) was used.

Example 3 (Experiment E1): Inventive raw material mixture (here: plasticizer mixture)

• - 5 bis 10 Massen-% an TDAE und
• - entsprechend 95 bis 90 Massen-% Gummigranulat aus Altreifen mit einer mittleren Partikelgröße von 2 bis 5 mm, wobei keine einzelnen Partikel mit einem Durchmesser von größer als 10 mm vorlagen und mindestens 90 Massenprozent der vulkanisierten Kautschukpartikel eine Partikelgröße im Bereich von 1 bis 6 mm aufwiesen,

in einem Innenmischer zu einer Vormischung vorvermischt wurden. Anschließend wurde die Vormischung in einen Zweischneckenextruder mit einem inneren Extruderdurchmesser d_inner von 40 mm, einer Länge L von 56-mal dem inneren Extruderdurchmesser d_inner und einem Verhältnis V von innerem zu äußerem Extruderdurchmesser von 1,56 gefüllt und, während eine Temperatur in dem Extrusionskopf im Bereich von 130 °C bis 140 °C vorlag, extrudiert.A raw material mixture according to the invention was prepared by

• - 5 to 10% by mass of TDAE and
• - Accordingly, 95 to 90% by mass of rubber granules of scrap tires having an average particle size of 2 to 5 mm, with no individual particles having a diameter greater than 10 mm and at least 90 percent by mass of the vulcanized rubber particles having a particle size in the range of 1 to 6 mm had,

in an internal mixer were premixed to a premix. Then the premix was _intra charged into a twin-screw extruder having an inner extruder diameter d of 40 mm, a length L of 56 times the inner extruder diameter d _intra and a ratio V of inner to outer extruder diameter of 1.56 and, during a temperature in the Extrusion head in the range of 130 ° C to 140 ° C, extruded.

Production of various ready mixes

The respective raw material mixture (regenerator 1 not according to the invention, non-inventive regenerated material 2 or the plasticizer mixture according to the invention) was first obtained by means of an internal mixer
mixed in a first mixing stage by adding a standard mixture to a rubber mixture
and subsequently became
in a second mixing stage, the rubber mixture resulting in the first mixing stage is mixed by addition of vulcanizing agents to give a finished mixture.

The respective resulting final mixture was composed as follows: TABLE 1 Composition of the ready mixes; other ingredients: mixer Mass fraction (phr) Ingredients - Cf. Exp. V1 Ingredients - Cf. Exp. V2 Ingredients - Exp. E1 1 28 Regenerate 1 Regenerate 2 plasticizer mixture 1 25 NO NO NO 1 50 BR BR BR 1 25 SBR SBR SBR 1 40 Carbon black N 550 Carbon black N 550 Carbon black N 550 1 3 TDAE TDAE TDAE 1 10 other ingredients other ingredients other ingredients 2 1.5 TBBS TBBS TBBS 2 1.5 sulfur sulfur sulfur Anti-aging agent, antiozonant wax, zinc oxide, stearic acid. The 100% rubber, which by default defines the unit "phr", is composed in Table 1 of the 25 phr NR, 50 phr BR and 25 phr SBR. The vulcanized rubber particles (here: rubber granules from scrap tires) from the plasticizer mixture according to the invention are not counted to the 100% rubber for the definition of the unit "phr" in Table 1.

Evaluation of the experimental results:

The results of the measurements described above are shown in Table 2. Table 2: Experimental data of the ready-mixed mixtures and test specimens prepared according to the invention and not according to the invention property unit Comp Exp. V1 Comp Exp. V2 Exp. E1 Not according to the invention Not according to the invention Erfind.-under Used raw material mixture Regenerate 1 Regenerate 2 plasticizer mixture ready-mix Mooney viscosity MU 55 70 51 specimens Shore A hardness Sh A 55 58 56 elongation % 449 454 469 tensile strenght MPa 12 15 14 "Fatigue-to-failure" test kC 67 203 2000

From Table 1 it can be seen that a finished mixture, which was prepared using a raw material mixture according to the invention, has a lower Mooney viscosity and thus better processable or processable than the other two non-inventive finished mixtures.

In addition, the test specimens according to the invention in the "fatigue-to-failure" test show a higher resistance to cracking, since test specimens from a ready-to-use mixture according to the invention with 2000 kC were significantly longer lasting than the other two test specimens not according to the invention. It should be emphasized that this could be achieved without significantly deteriorating the mechanical properties such as Shore A hardness, elongation at break and tensile strength. The elongation at break could even be slightly improved (from 449% (Regenerat 1), or 454% (Regenerat 2) to 469%) compared to the two test specimens not according to the invention prepared.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• CN 101117022 A [0005]
• DE 2049974 A1 [0005]
• US 2012/0184634 A [0005]
• DE 102006004062 A1 [0099]

Cited non-patent literature

• DIN EN ISO 4610: 2002-04 [0108]

Claims (10)

A process for preparing a raw material mixture, characterized in that the process comprises at least the following step: a) extruding one or more plasticizers and vulcanized rubber particles in an extrusion apparatus with an extrusion head to form a raw material mixture. Method according to Claim 1 , characterized in that the vulcanized rubber particles have an average particle size in the range of 0.3 to 30 mm. Method according to one of the preceding claims, characterized in that the raw material mixture has a Mooney viscosity at 100 ° C in a range of 10 to 200 Mooney units. Method according to one of the preceding claims, characterized in that the or at least one of the plurality of plasticizers is selected from the group consisting of: MES (mild extraction solvate), RAE (Residual Aromatic Extract), TDAE (treated distillate aromatic extract), Rubber- to-liquid oils (RTL) and biomass-to-liquid oils (BTL), rapeseed oil, batches and liquid polymers. Method according to one of the preceding claims, characterized in that in the extrusion head of the extrusion device, a temperature in the range of 70 ° C to 250 ° C is present. Method according to one of the preceding claims, characterized in that in the extrusion head of the extrusion device, a pressure in the range of 10 bar to 500 bar is present. Method according to one of the preceding claims, characterized in that in the raw material mixture, the ratio of the total mass of vulcanized rubber particles to the total mass of plasticizers in the range of 500: 1 to 1: 1. A process for preparing a rubber composition, characterized in that the process comprises the steps of a process as defined in any one of the preceding claims and additionally comprising at least the following step: b) preparing a rubber mixture by mixing the raw material mixture with unvulcanized rubber ingredients and optionally other ingredients , Method according to one of the preceding claims, characterized in that the vulcanized rubber particles and / or the unvulcanized rubber components contain at least one rubber selected from the group consisting of butadiene rubber (BR), styrene-butadiene rubber (SBR), natural polyisoprene (NR ), Butyl rubber (IIR) and synthetic polyisoprene (IR). Process for the preparation of a vulcanizate, characterized in that the process comprises the steps or steps as described above in one of the Claims 1 to 7 or the Claims 8 to 9 c) and additionally comprising the following steps: c) mixing the raw material mixture or the rubber mixture with vulcanizing agents into a finished mixture and d) vulcanising the finished mixture prepared in step c) so that a vulcanizate results.