Equipment for producing plastic melts and its application

Abstract

The invention relates to an apparatus (1) for producing a plastic melt (2) for porous membranes, in particular thin-sheet membranes, comprising a planetary roller extruder (3). The planetary roller extruder is used to produce a flowable plastic melt (2) from a thermoplastic plastic. The planetary roller extruder (3) has a filling opening (3a) and a discharge side (3b), the discharge side being used to discharge the plastic melt (2); in addition, a melt pump (4) is provided. The discharge side (3b) of the planetary roller extruder (3) is connected to an inlet side (4a) of the melt pump (4) arranged downstream for further conveying the plastic melt (2). The connection is constructed as a pressure channel or a shielded pressure line (6) shielded from the ambient atmosphere. The planetary roller extruder (3) and the melt pump (4) are constructed and / or can be driven so that the plastic melt (2) is waiting for processing or can be delivered under pressure on the inlet side (4a) of the melt pump (4).

Description

Technical Field

[0001] The invention relates to a device for producing a plastic melt for a porous film, in particular in the form of a laminar film, and to the use of such a device for producing a plastic melt for such a porous film, in particular in the form of a laminar film. Background Art

[0002] In order to produce stretched porous membranes, such as sheet membranes for filtration, desalination, but also as separators / barrier membranes for batteries, such as lithium-ion batteries, the membranes consist of polymers such as polypropylene (PP), polyethylene (PE) and powdered UHMWPE (ultra-high molecular weight PE) or HMWPE (high molecular weight PE) or HDPE (high density PE), and before stretching (Versettling) with liquid components, especially plasticizers (hereinafter also referred to as solvents or softeners, respectively, and can include, for example, paraffin oil, hydrocarbons, petroleum hydrocarbons, white mineral oil), the polymers for forming the pores must be uniformly mixed, heated and plasticized. The uniformly added plasticizer ensures that free spaces are formed in the polymer, which lead to the formation of pores during subsequent stretching and washing off or evaporation of the plasticizer. The aim here is to distribute the plasticizer uniformly and finely in the polymer to be melted / already melted in the extruder so that as many and fine pores as possible are generated during stretching and washing off or evaporation of the plasticizer.

[0003] According to the standard, a twin-screw extruder running in the same direction is used for this purpose, and the polymer with the liquid component, i.e. the plasticizer, is fed to the twin-screw extruder in a pre-mixed suspension (slurry). Due to the simplified operation, the components are often fed to the twin-screw extruder individually. When the components are added individually to the extruder, uniform mixing places high demands on the mixing quality of the extruder. A uniform mixing result can be achieved mainly by a long residence time, a large mixing volume and a high rotation speed. Since when the rotation speed increases, the material temperature quickly reaches the maximum permissible material temperature applicable for explosion protection (depending on the autoignition temperature of the liquid component) due to the friction heat input, and the melt can only discharge heat to a limited extent via the temperature-controlled cylindrical jacket, only a limited rotation speed is possible. In particular, when using UHMWPE with a high molecular weight of more than about 600,000 g / mol, the output is further reduced. If the liquid component, i.e., especially the plasticizer, is flammable, the processing temperature window is shifted downward again due to the explosion protection, so that the maximum possible rotation speed must be reduced again, which leads to a reduction in output due to the poor homogenization power. In order to achieve the throughputs required on the market, twin-screw extruders having relatively large screw diameters and long travel lengths of 50-70 L / D (L / D=ratio of screw length to screw diameter) must be used. Summary of the invention

[0004] Since market requirements on the raw materials used and the production efficiency are constantly increasing, but machine costs must be kept low, it was an object of the present invention to find alternative extrusion concepts for producing porous membranes or foils, such as battery separator films (BSF).

[0005] The device for manufacturing a plastic melt for a porous film, especially a thin film, according to the present invention comprises a planetary roller extruder. The planetary roller extruder is used to manufacture a flowable plastic melt from a thermoplastic. The planetary roller extruder has a filling opening for introducing an initial material and a discharge side for outputting the plastic melt. In addition, a melt pump is provided. The melt pump is necessary because a high material pressure can only be conditionally established by the planetary roller extruder. However, because a melt line (pressure line), a melt filter and a wide-slit nozzle must be passed through in direct film extrusion, a material pressure greater than 40 bar, 50 bar, 60 bar, 70 bar or greater than 80 bar is required. Therefore, in order to establish pressure, a melt pump is directly connected to the planetary roller extruder. This connection is carried out so that the discharge side of the planetary roller extruder is connected to the inlet side of the melt pump arranged downstream for continuing to convey the plastic melt. Here, the connection is constructed as a shielded pressure channel or a shielded pressure line relative to the ambient atmosphere. The use of a shielded pressure channel allows the melt pump to be directly installed on the discharge side of the planetary roller extruder. Use shielded pressure line to allow planetary roller extruder to be installed at a distance from melt pump in space. Planetary roller extruder and melt pump are constructed and / or can be driven in this way so that plastic melt is waiting for processing or can be delivered under pressure on the inlet side of melt pump.

[0006] Particularly advantageously, it can be found that, in order to manufacture porous films, especially porous films in the form of thin film, planetary roller extruders provide particularly good results. In the field of plastics, these have been used only for the processing of PVC so far. Therefore, planetary roller extruders include a very large surface compared to other extruders, through which the plastic melt can be kneaded. It is also particularly advantageous to deliver the plastic melt to the melt pump under pressure, because the undefined degassing or evaporation of the used liquid components, i.e., especially plasticizers (softeners) for the porous film can be prevented thereby. At the same time, the plastic melt is optimally mixed by high pressure, and air is pressed out of the plastic melt at the same time. In addition, the melt pump is used for material pressure establishment (as will be explained below), and in addition for leveling material pressure fluctuations. In general, a particularly uniform plastic melt can be achieved in a relatively compact device by using a planetary roller extruder. In addition, using this planetary roller extruder allows liquid components, i.e., especially plasticizers, to be uniformly mixed into polymers and liquid components, i.e., especially plasticizers, can be directly sprayed into the extruder or near the extruder. Furthermore, such a planetary roller extruder can be constructed in a modular manner and allows gentle material preparation with high mixing efficiency. In addition, a controlled material temperature control can be achieved until discharge.

[0007] It is particularly advantageous if the pressure is greater than 4 bar, 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, 13 bar, 15 bar, 17 bar or greater than 19 bar, but preferably less than 21 bar, 18 bar, 16 bar, 14 bar or 12 bar, at which the plastic melt is waiting to be processed on the inlet side of the melt pump or can be delivered to the inlet side of the melt pump. It is thereby achieved that the plastic melt is optimally mixed and air contained in the bulk material (for example in the powdered polymer or between the powder particles) can be pressed out of the plastic melt. This pressure also prevents the liquid component from escaping and from being unavailable or no longer available in sufficient concentration in a later process stage. In principle, the addition of the bulk material can be carried out under a nitrogen atmosphere in order to keep the oxygen content low. Thus, oxidation of the plastic melt and the accompanying material degradation can be prevented, as well as possible explosions of the liquid component.

[0008] In another example of the device according to the invention, the pressure at which the plastic melt is waiting to be processed on the inlet side of the melt pump or the plastic melt can be delivered to the inlet side can be increased by configuring the melt pump to reduce its pump speed. This reduced pump speed causes the plastic melt to be blocked and accumulated from the inlet side of the melt pump to the discharge side of the planetary roller extruder (and into the planetary roller extruder), wherein this blockage and accumulation reacts to the continuous material flow of other plastic melts (the addition of the starting components (polymer and liquid components) is preferably not reduced), so that an increase in pressure occurs. Therefore, the material pressure between the planetary roller extruder and the melt pump is set in particular by the ratio between the addition of the starting components (metering of polymer and liquid components) and the speed of the melt pump. When the starting components are added constantly and in particular when the speed of the planetary roller extruder is constant, the slower the melt pump rotates, the further the material is blocked and accumulated in the direction of the planetary roller extruder. This continuous material flow in the planetary roller extruder reacts to the material blockage and accumulation as already explained, thereby causing pressure to build up. In principle, the pressure on the outlet side of the planetary roller extruder (on the extruder head) is gradually increased until no air is visible in the plastic melt. This is achieved in particular at a material pressure of more than 5 to 10 bar.

[0009] The air is preferably degassed only in a reverse direction. This is achieved in that there are no possible air openings in the area from the filling opening of the planetary roller extruder to the inlet side of the melt pump, so that during the pressure build-up of the plastic melt, the air entrained in the plastic melt is squeezed out of the plastic melt and pushed back in the direction of the filling opening and only then degassed from the filling opening. This is also referred to as reverse degassing. This also has the advantage that only this one position has to be fixed specifically (especially when using flammable liquid components).

[0010] In addition, another special embodiment of the device is that the filling opening is designed as a "common" filling opening, into which not only polymers, especially powdered polymers, and fillers, especially in the form of liquid components, such as softeners, i.e., for example, liquid hydrocarbons, such as paraffin oil, but also liquid solvents can be filled together. Since polymers and liquid components are added simultaneously in the planetary roller extruder, good homogenization is guaranteed at moderate material temperatures. The addition should preferably be carried out under a nitrogen atmosphere. The addition of liquid components can (also) be carried out at other locations of the planetary roller extruder.

[0011] In a preferred embodiment of the device, a drive device (e.g., an electric motor) is provided for driving the planetary roller extruder. The planetary roller extruder comprises n roller cylinders, wherein n≥1, 2, 3, 4, 5, 6, 7 or n≥8. In this case, such a roller cylinder comprises, in particular, an inner toothed outer sleeve (inner toothed cylinder sleeve), which in particular has a large outer diameter. A toothed planetary screw is arranged between them. The toothed planetary screw is driven by a central screw that is also toothed. The central screw is arranged in the center of the inner toothed cylinder sleeve. The planetary screw is arranged between the cylinder sleeve and the central screw. Good results are achieved with at least 3 planetary screws per roller cylinder and up to 18 planetary screws depending on the type of device. On the one hand, the central screw and the planetary screws mesh, and on the other hand, the planetary screws mesh with the inner toothed cylinder sleeve.

[0012] The planetary screw is planetarily rotated between the internally toothed cylinder sleeve and the central screw by the driven central screw and the plastic melt (polymer melt) is rolled into a thin layer. The large surface of the rolled polymer, i.e. the rolled plastic melt, formed thereby can realize both controlled energy input and controlled energy output. Here, the central screw passes through a plurality of roller cylinders, in particular through all roller cylinders. The central screw is in particular constructed in a single piece, but can also be composed of a plurality of components, which are connected to each other in a non-rotatable manner (for example, screwed to each other, plugged into each other and / or welded). The first roller cylinder preferably includes a filling opening and the last roller cylinder includes a discharge side. Preferably, the planetary roller extruder includes four or more than four, six or eight or more than eight roller cylinders. The individual roller cylinders are preferably screwed to each other, thereby realizing a modular structure of the planetary roller extruder.

[0013] The more roller cylinders that are provided, the higher the specific output with a homogeneous melt. Particularly good results are achieved with six to eight or more roller cylinders, since a higher number of roller cylinders results in a longer planetary roller extruder, whereby the residence time and mixing time are also extended. The plastic melt is very homogeneous in this case. At the same time, the temperature profiles for the individual roller cylinders can be set more individually (e.g., hotter at the filling opening and cooler on the discharge side). This will be explained in more detail below.

[0014] The internal toothing of the cylinder sleeve, the toothing of the central spindle and the toothing of the planetary spindles are preferably 45° helical toothings (= helical toothings), thereby creating a forward flow of the rolled plastic melt.

[0015] The planetary screws can also be granular, which means that the 45° helical toothing is interrupted from time to time along the longitudinal axis or at regular intervals along the longitudinal axis of the planetary screw. The same preferably also applies to the central screw, which is also interrupted, in particular at the transition from one roller cylinder to the other. Due to the many individual mass flow profiles, this interrupted helical toothing (helical toothing) leads to very good cross mixing.

[0016] The length of each planetary screw preferably corresponds approximately to the length of the roller cylinder. In particular, the planetary screw is arranged only within the respective roller cylinder in most roller cylinders and does not extend beyond the roller cylinder into the adjacent roller cylinder. However, it is particularly suitable for the first two adjacent roller cylinders that the roller cylinder also comprises a continuous planetary screw. Such a planetary screw is longer than the respective roller cylinder. Therefore, the planetary screw extends both in the first roller cylinder and in the second roller cylinder, i.e. is arranged jointly in both roller cylinders.

[0017] In this case, preferably between two first adjacent roller cylinders a toothed intermediate ring is inserted, which reflects the inner toothing of the cylinder sleeve. Here, the intermediate ring acts as a connecting piece between the two roller cylinders, thereby enabling the use of particularly simple continuous planetary screws.

[0018] In another preferred embodiment, a dispersion ring is used between two adjacent roller cylinders. This applies in particular from the second roller cylinder up to the nth roller cylinder (a toothed intermediate ring is preferably used between the first and second roller cylinder). The dispersion rings preferably differ from one another in the size of their annular gaps. A dispersion ring having a larger annular gap than the other dispersion rings arranged in the direction of the discharge side is inserted between the second and third roller cylinders. The dispersion ring between the second and third roller cylinders preferably has an annular gap of greater than 1 mm, 1.2 mm, 1.4 mm, 1.7 mm or 1.9 mm and preferably less than 2.1 mm, 1.8 mm or 1.6 mm. The dispersion ring connected to the annular gap preferably has an annular gap of greater than 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm or 1.2 mm and preferably less than 1.3 mm or 1.1 mm. Therefore, the dispersion ring between the second and third roller cylinders has a larger annular gap, because additional inhomogeneities can also occur here, which can lead to blockage of the transition between the two roller cylinders if the annular gap is too small. In the further course of the planetary roller extruder, the plastic melt is largely homogenized, whereby the risk of blockage is reduced and smaller annular gaps can be used.

[0019] In a particular embodiment of the device according to the invention, a metering device is also provided. The metering device comprises at least one metering mechanism (e.g., gravimetric) for at least one polymer and a metering pump and at least one injection device for a liquid component. The metering device is configured to distribute the metered polymer and the metered liquid component directly into a first roller cylinder via a filling opening, where the polymer and the liquid component are mixed with each other. Alternatively to this, the metering device is configured to add the metered polymer and the metered liquid component to a side feeder with one or two conveying screws, in which the mixing of the polymer and the liquid component takes place, wherein the conveying screw then gives or outputs the mixture into the first roller cylinder through the filling opening. As a metering pump, for example, a diaphragm pump or a gear pump can be used. By adding the polymer and the liquid component simultaneously, very good homogenization is ensured at a moderate material temperature. The polymer is present in particular as a powder. So far, it has also not been possible to meter a powdered polymer with a liquid component, in particular a liquid component in the form of a plasticizer, into a common side feeder in this way.

[0020] In another embodiment, the metering device also includes one or more additional injection devices. The one or more additional injection devices are arranged along the planetary roller extruder. In particular, they are respectively arranged on the transition area between a roller cylinder and its adjacent roller cylinder. Through the one or the other injection device, additional accurately metered amounts of the same or other liquid components can be injected into the planetary roller extruder or in the transition area of ​​the planetary roller extruder.

[0021] Preferably, the metering device is configured to set the ratio of the amounts of polymer and liquid component supplied to the planetary roller extruder (3) such that

[0022] a) 80 to 50 parts by weight of the liquid component may be added to 20 to 50 parts by weight of the polymer; or

[0023] b) 75 to 55 parts by weight of the liquid component may be added to 25 to 45 parts by weight of the polymer; or

[0024] c) 70 to 60 parts by weight of the liquid component may be added to 30 to 40 parts by weight of the polymer.

[0025] In another preferred embodiment, the device further comprises at least one pressure sensor, which is arranged on the nth roller cylinder or between the nth roller cylinder and the inlet side of the melt pump and is used to measure the pressure of the plastic melt. In addition, a control device is provided, which receives and evaluates the measured value and is therefore configured to control the metering device in terms of its output, the drive device in terms of the rotation speed of the central screw and the melt pump in terms of the pump rotation speed, so that the pressure measured by at least one pressure sensor reaches a predetermined reference value. If the pressure is too low, the rotation speed of the melt pump can be slowed down, for example. Alternatively or in addition, more material can also be added by the metering device. If the pressure is too high, the rotation speed of the melt pump can be increased, or less initial material can be added to the filling opening by the metering device. As explained, cavitation in the plastic melt should be avoided. For this reason, the material pressure on the discharge side of the planetary roller extruder and on the inlet side of the melt pump must preferably be at least 5-10 bar. In addition, the speed of the planetary roller extruder can also be reduced while the output remains unchanged in order to achieve a higher specific output [kg / h / rpm] and thus a higher filling degree in the moving part. The higher filling degree in the planetary roller extruder increases the material pressure in the planetary roller extruder, which helps to degas the air earlier.

[0026] By using a planetary roller extruder, a large surface of the rolled plastic melt is obtained. This allows a controlled energy input or a controlled energy output by thermal heating / cooling. In a special embodiment of the device according to the invention, the central screw is completely or along most of its length through at least one fluid channel (preferably two (parallel) fluid channels are provided, which are respectively traversed by fluids in opposite directions, i.e., an inflow channel and a return channel). In addition, a pump device and a heating and / or cooling device are provided, which are configured to adjust the temperature of a fluid (e.g., (hot) oil or water) to a certain temperature and guide the fluid through at least one fluid channel, so as to thereby adjust the temperature of the plastic melt to a certain temperature through the central screw.

[0027] In addition to the central spindle, the roller cylinders can preferably also be temperature-controlled (in particular separately). The roller cylinders comprise at least one temperature-control channel. The pump device and the temperature-control device are provided and designed to control the temperature of a fluid (for example (hot) oil or water) to a certain temperature and to guide the fluid through at least one temperature-control channel of the respective roller cylinder, so that the plastic melt is thereby temperature-controlled to a certain temperature through the roller cylinders. The at least one respective temperature-control channel of each roller cylinder is separated from the temperature-control channel of the respective other roller cylinder, so that the temperature-control channels of the individual roller cylinders can be temperature-controlled differently, wherein the temperature of the fluid in the first roller cylinder can be hotter than the temperature of the fluid in the nth roller cylinder. The term "temperature-control" is to be understood here as heating and cooling of the plastic melt (the fluid is colder than the plastic melt).

[0028] In another optional embodiment, the melt pump can also be electrically temperature-controlled or temperature-controlled with hot oil (heatable or coolable). The temperature is basically detected by a temperature sensor and transmitted to the control device. The control device preferably detects all process parameters (temperature, pressure) at different positions of the device and generates corresponding adjustment parameters, which are output to the drive device for the central screw or to the drive device for the melt pump or to the metering device. When the maximum allowable material temperature is exceeded, the cut-off (explosion protection) is preferably triggered. Differently, the speed of the planetary roller extruder and the output of the melt pump are adjusted by the measured pressure.

[0029] Furthermore, an application is described. Thus, the device can be used to produce a plastic melt for porous films, in particular thin-film films, wherein in this case, polymers and at the same time liquid components, in particular plasticizers (softeners), are fed to the filling opening. As already explained, planetary roller extruders have not been used in the past for producing porous films. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Various embodiments of the present invention will be described below by way of example with reference to the accompanying drawings. The same objects have the same reference numerals. The corresponding figures of the accompanying drawings show in detail:

[0031] Figure 1 An overview of a first exemplary embodiment of a device for producing a plastic melt for porous films, in particular thin-film films;

[0032] Figure 2 An overview of a second specific embodiment of an apparatus for producing a plastic melt for porous films or foils is shown;

[0033] Figure 3 A perspective view showing a partially opened roller cylinder of a planetary roller extruder; and

[0034] Figure 4 A perspective view showing a cross section of a roller cylinder of a planetary roller extruder. DETAILED DESCRIPTION

[0035] Figure 1A device 1 for producing a plastic melt 2 for a porous film or a thin film is shown. The device comprises a planetary roller extruder 3 having a filling opening 3a and a discharge side 3b. The filling opening 3a is in particular a lateral filling opening 3a. In addition, a melt pump 4 and a wide-slot nozzle 5 are provided. The discharge side 3b of the planetary roller extruder 3 is connected to the downstream inlet side 4a of the melt pump 4 for further conveying the plastic melt 2. In this case, the connection is configured as a pressure line 6 shielded from the ambient atmosphere. The pressure line 6 is preferably shorter than 500 cm, 400 cm, 300 cm, 200 cm, 100 cm, 50 cm, 40 cm, 30 cm, 20 cm or shorter than 10 cm. The pressure line is preferably longer than 5 cm, 15 cm, 25 cm, 35 cm, 45 cm, 150 cm, 250 cm, 350 cm or longer than 450 cm. Planetary roller extruder 3 and melt pump 4 are constructed and / or can be driven so that plastic melt 2 is waiting for processing on the inlet side 4a of melt pump 4 under pressure or can be delivered to the inlet side 4a under pressure. Wide-slot nozzle 5 is connected to the discharge side 4b of melt pump 4. What is not shown is that flushing valve and / or melt filter can also be optionally arranged between the discharge side 4b of melt pump 4 and wide-slot nozzle 5. Melt pump 4 and / or pressure line 6 and / or flushing valve and / or melt filter can be electrically temperature-controlled, especially electrically heated, so that plastic melt 2 is always within the processing temperature window, and therefore especially has corresponding viscosity. This temperature control can also be performed by hot oil. The viscosity of the plastic melt 2 discharged on wide-slot nozzle 5 is especially in the range of 1000 to 4000 Pa*s. The wide slot nozzle 5 has in particular a slot width of greater than 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 1000 mm, 1200 mm, 1400 mm, 1600 mm, 1800 mm, 2000 mm, 2200 mm, 2400 mm, 2600 mm, 2800 mm or greater than 3000 mm, but preferably less than 3100 mm, 2900 mm, 2700 mm, 2500 mm, 2300 mm, 2100 mm, 1900 mm, 1700 mm, 1500 mm, 1300 mm, 1100 mm, 900 mm or less than 650 mm.The wide slot nozzle 5 has a slot height greater than 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm, 2.3 mm, 2.5 mm, 2.7 mm, 2.9 mm or greater than 3.1 mm, but preferably less than 3.2 mm, 3.0 mm, 2.8 mm, 2.6 mm, 2.4 mm, 2.2 mm, 2.1 mm, 2.0 mm, 1.8 mm, 1.6 mm, 1.4 mm, 1.2 mm, 1.0 mm, 0.8 mm, 0.6 mm, 0.4 mm or less than 0.2 mm.

[0036] The plastic melt 2 is discharged from the wide slot nozzle 5 onto a cooling roller 27 which is temperature-controlled (regulated) to a certain temperature and is optionally partially arranged in a water bath (not shown). A motor device (not shown) is designed to rotate the cooling roller 27 .

[0037] The pressure at which the plastic melt 2 is waiting to be processed on the inlet side 4 a of the melt pump 4 or can be delivered thereto is preferably greater than 5 to 10 bar.

[0038] This pressure can be increased by reducing the pump speed of the melt pump 4. While the material flow continues to flow constantly through the planetary roller extruder 3, the reduction in the pump speed leads to a jam accumulation of the plastic melt 2 from the inlet side 4a of the melt pump 4 in the direction of the outlet side 3b of the planetary roller extruder 3. The continued material flow of the additional plastic melt 2 counteracts this jam accumulation, so that an increase in pressure occurs in the region of the outlet side 3b of the planetary roller extruder 3. The jam accumulation of the plastic melt 2 preferably extends over less than 50%, 40%, 30%, 20% or less than 10% of the length of the planetary roller extruder 3.

[0039] Alternatively or additionally, it is also possible here to add additional starting material to the filling opening 3 a.

[0040] It is particularly important that there are no air openings in the area from the filling opening 3a of the planetary roller extruder 3 to the inlet side 4a of the melt pump 4. As already explained, this is achieved by a shielded pressure line 6 or usually by a shielded pressure channel (not shown). This causes the air entrained in the plastic melt 2 to be squeezed out of the plastic melt when the pressure of the plastic melt 2 is established (preferably greater than 5 to 10 bar) and, due to the lack of further openings, is pressed back in the direction of the filling opening 3a and is only degassed from the filling opening. These missing air openings also cause components or fillers in the plastic melt 2, such as liquid components, especially plasticizers (softeners), to continue to remain in the plastic melt 2 and can be used for subsequent processes. These fillers do not cause uncontrolled degassing, which is particularly critical if these fillers are easily flammable.

[0041] Preferably, a ventilation device is installed in the region of the filling opening 3 a , which ventilation device sucks gas or escaping air out of the filling opening 3 a and preferably feeds this air into a filter device.

[0042] It is also particularly advantageous that Figure 1 The filling opening 3a in the is configured as a common filling opening 3a for a polymer, in particular a powdered polymer, and for a filler, in particular a filler in the form of a liquid component, such as a liquid hydrocarbon or a plasticizer (softener). The liquid component can also be configured as a solvent.

[0043] When the polymer and the liquid component are fed together into the planetary roller extruder 3 or into the corresponding side feeder 7 (see Figure 2 ), particularly advantageous results could be achieved after extensive investigations. This is achieved by means of a metering device 8. The metering device comprises in particular at least one metering mechanism 9 for the gravimetric determination of at least one (e.g. powdered) polymer, optionally a processing aid, such as an antioxidant, and a metering pump device 10, which has at least one metering pump 10a, 10b and at least one injection device 11. The at least one metering mechanism 9 should be arranged as close as possible to the filling opening 3a or the side feeder 7 (the distance should be less than 100 cm, 80 cm, 60 cm, 40 cm, 30 cm, 20 cm or 10 cm), because the electrostatic charge of the powdered polymer is kept low thereby.

[0044] The metering device 8 is designed to meter the polymer and the liquid component and to discharge the polymer and the liquid component either directly through the filling opening 3a into the planetary roller extruder 3, where the polymer and the liquid component are mixed with each other (in Figure 1 ), or the polymer and the liquid component are distributed to a side feeder 7, which in turn includes one or two conveying screws, in which the polymer and the liquid component are mixed, wherein the conveying screw then outputs the mixture via the filling opening 3a to the planetary roller extruder 3. Here, uniform mixing has not yet occurred. In one or more conveying screws of the side feeder 7, the polymer is wetted with the liquid component. The polymer wetted with the liquid component is conveyed to the planetary roller extruder 3. Then, the portion of the liquid component is mixed in the planetary roller extruder 3, the polymer portion is melted, and the melt is homogenized.

[0045] The at least one gravimetric metering device 9 is connected to a polymer supply container 12 which is filled with a preferably powdered polymer.

[0046] exist Figure 1In addition to at least one first metering pump 10a of the metering pump device, another metering pump 10b is shown, which can also be a component of the metering pump device 10. A first storage container 13a and a second storage container 13b for the first and second liquid components are also shown. The first metering pump 10a is connected to the first storage container 13a. The second metering pump 10b is in turn connected to the second storage container 13b. The control device 14 controls the metering device 8 and thus predetermines the mixing ratio between the polymer and the liquid component. The metering pumps 10a, 10b are preferably piston diaphragm pumps or gear pumps. A flow meter 15 (see Figure 15 ) can optionally be connected in front of or behind the respective metering pumps 10a, 10b. Figure 2 ), in particular a flow meter in the form of a Coriolis flow meter 15. The flow meter is in turn connected to a control device 14.

[0047] In order to improve the metering accuracy of the liquid component, a pulsation damper (bubble accumulator) is preferably used between the metering pump 10 a , 10 b and the flow meter 15 , which dampens or evens out the pulsations originating from the metering pump 10 a , 10 b .

[0048] In addition, there is the possibility of preheating the liquid component to the desired temperature (50 to 100° C.) already in the storage container 13a, 13b and / or between the pumping point and the injection point. The liquid component, ie, in particular the plasticizer, is preferably guided through a heat exchanger after the metering pump 10a, 10b, where it is preheated to the desired temperature by means of hot oil. The line between the heat exchanger and the injection nozzle is equipped with a follow-up heater to keep the preheated liquid component at a certain temperature. A temperature sensor (not shown) can measure the temperature, whereby the heating power can be adjusted.

[0049] The metering device 8 is configured to set the ratio of the amount of polymer and liquid component supplied to the planetary roller extruder 3, wherein 80 to 50 parts by weight of the liquid component can be added to 20 to 50 parts by weight of the polymer. Preferably, 75 to 55 parts by weight of the liquid component can be added to 25 to 45 parts by weight of the polymer, and even more preferably, 70 to 60 parts by weight of the liquid component can be added to 30 to 40 parts by weight of the polymer.

[0050] In particular, battery separators can be produced in this way, since gentle material preparation, good homogenization and dispersion, and material temperature control are possible due to the large polymer surface and the temperature controllability of the central screw 20. In battery separators (UHMWPE / HMWPE), the polyethylene (PE) content is 30% to 40% and the liquid component content is 60% to 70%.

[0051] The portion of the liquid component can be sprayed via a spraying point or also via a plurality of spraying points (distributed over the travel length).

[0052] exist Figure 1 , a drive 16 is also shown, which serves to drive the planetary roller extruder 3. This is preferably an electric motor.

[0053] The planetary roller extruder 3 comprises n roller cylinders 3 1 to 3 n , where n≥1, n≥2, n≥3, n≥4, n≥5, n≥6, n≥7, n≥8, n≥9 or n≥10. Figure 1 Six roller cylinders 3 are shown 1 to 3 6 .

[0054] These n roller cylinders 3 1 , …, 3 n The roller cylinders 3 are arranged adjacent to one another along their longitudinal axis 17 and are fastened to one another, in particular screwed to one another. 1 , …, 3 n In addition, the sealing should be performed so that the device 1 can be regarded as permanently technically sealed. In this case, the sealing can be metallic or by means of a sealing element, which comprises, for example, PTFE, (composed of or including fluororubber or fluorocarbon rubber), aluminum, graphite, graphite oil, etc. or composed thereof. The planetary roller extruder 3 is thus constructed in a modular construction. Here, the planetary roller extruder may include any number of roller cylinders 3. 1 , …, 3 n In particular, the roller cylinder 3 can be adjusted according to the plastic melt 2 to be produced. 1 , …, 3 n The number of

[0055] Can be obtained from Figure 2 , 3 The precise structure of the planetary roller extruder 3 is known from FIG. Figure 1 As shown in FIG. , the embodiment of the planetary roller extruder 3 is Figure 2 Also includes six roller cylinders 3 1 , …, 3 6, the six roller cylinders are arranged along their longitudinal axis 17 and are screwed to each other and / or connected to the fixture. As explained, the addition of the starting component to the filling opening 3a is carried out via the side feeder 7. In this case, the metering device 8 or the metering pump device 10 only includes the first metering pump 10a. Of course, multiple metering pumps 10a can also be used. The first metering pump 10a is not directly connected to the first storage container 13a of the liquid component in this case. More precisely, there are also first and second storage containers 13a, 13b, wherein the first metering pump 10a is either connected or connectable to the first storage container 13a or connected or connectable to the second storage container 13b through a ball valve 18. The position of the ball valve 18 can be selected either manually or automatically by a setting mechanism not shown. The setting mechanism can be controlled by the control device 14. Of course, it is also possible to use only exactly one storage container 13a. In this case, the ball valve 18 can be omitted. The number of storage containers 13 a , 13 b is arbitrary, and a plurality of storage containers 13 a , 13 b permits a more rapid change of the liquid components in continuous operation.

[0056] The drive device 16 in turn drives the planetary roller extruder 3. 1 An addition cylinder 19 is also provided between the planetary roller extruder 3 and the device 1. The addition cylinder can be used to produce other films. The addition cylinder 19 comprises only one conveying screw, which is also oriented in the longitudinal direction 17 of the planetary roller extruder 3. This addition cylinder 19 is not essential for the device 1 according to the invention, but it particularly illustrates the modular design of the device as a whole and of the planetary roller extruder 3. The addition cylinder 19 is provided in particular by means of a not shown The shaft seal (composed of or including fluororubber or fluorocarbon rubber) seals in such a way that no plastic melt 2 or starting components (polymer or liquid component) can escape into the addition cylinder.

[0057] exist Figure 3 An exemplary roller cylinder 3 is shown in 3 It should be noted that the entire planetary roller extruder 3 is penetrated by a central screw 20. The central screw extends through all roller cylinders 3. 1 , …, 3 n The central screw 20 is toothed. In addition, each roller cylinder 3 1 , …, 3 n The central screw 20 and the m planetary screws 22 are arranged on the corresponding roller cylinders 3. 1 , …, 3n The planetary screws 22 are arranged here between the central screw 20 (in the center) and the cylinder sleeve 21. Preferably, only the central screw 20 can be driven by the drive device 16, wherein the m planetary screws 22 roll on the central screw 20 and the cylinder sleeve 21 by the rotation of the central screw 20.

[0058] It is also shown that the toothing of the cylinder sleeve 21 , the central spindle 20 and the planetary spindles 22 is a 45° helical toothing (helical toothing), which results in a forward flow of the plastic melt 2 and at the same time presses it out.

[0059] The cylinder sleeve 21 can also be fixed and surrounded by the outer sleeve 23 .

[0060] about Figure 2 , the planetary screw 22 is in most roller cylinders 3 1 , ..., 3 n Only arranged in the corresponding roller cylinder 3 1 , ..., 3 n and does not extend from the roller cylinder to the adjacent roller cylinder 3 1 , ..., 3 n For the first two adjacent roller cylinders 3 1 , 3 2 The first two adjacent roller cylinders preferably comprise a continuous planetary screw 22, which is arranged not only in the first roller cylinder 3 1 and arranged in the second roller cylinder 3 2 In order to enable the planetary screw to roll well, it is preferred that the first two adjacent roller cylinders 3 1 , 3 2 A toothed intermediate ring 25 is inserted between the cylinder sleeve 21 and the intermediate ring 25. The toothed intermediate ring 25 reflects the inner toothing of the cylinder sleeve 21. Figure 2 As shown in FIG. 3 , in the roller cylinder 3 1 , …, 3 n In particular, in the first roller cylinder 3 1 An additional toothed intermediate ring 25 is also used. The additional toothed intermediate ring is preferably mounted on the first roller cylinder 3. 1 The middle part of.

[0061] At least from the second roller cylinder 3 2 Until the nth roller cylinder 3 is preferably n , respectively, in two adjacent roller cylinders 3 2 , …, 3 n A dispersion ring 26 is arranged between the second roller cylinder 3 2 On (to the third roller cylinder 3 3 The dispersion ring 26 preferably has a larger value than that of the n-1th roller cylinder 3 n-1With the nth roller cylinder 3 n Preferably, only the first dispersion ring 26, ie the dispersion ring arranged closest to the filling opening 3a, is provided with a larger annular gap. The annular gaps of all other dispersion rings 26 are preferably of the same size.

[0062] The teeth of the central screw 20 are connected from a roller cylinder 3 1 , …, 3 n-1 To the adjacent roller cylinder 3 2 , …, 3 n The same applies to the toothing of the planetary screws 22. In principle, these planetary screws can also be interrupted at (regular) intervals, whereby the cross-mixing is increased.

[0063] In this example, the metering device 8 further comprises one or more further injection devices 11, wherein the one or more further injection devices 11 are respectively injected along the planetary roller extruder 3, in particular from a roller cylinder 3. 1 , ..., 3 n To another adjacent roller cylinder 3 1 , ..., 3 n The additional injection devices 11 are arranged on the transition region of the roller cylinder 3 and are configured to inject additional precisely metered amounts of the liquid component into the planetary roller extruder 3. These additional injection devices 11 can also be installed in the corresponding roller cylinder 3 1 , ..., 3 n The same liquid component or different liquid components can be injected respectively. The amount can also vary from injection device 11 to injection device 11 along the planetary roller extruder 3.

[0064] exist Figure 2 The use of different pressure sensors 30, 31 is also shown in FIG. 3. Preferably, the pressure sensor 30 is arranged at the nth roller cylinder 3 n On or arranged on the nth roller cylinder 3 n and the inlet side 4a of the melt pump 4 and is designed to measure the pressure in the plastic melt 2. The control device 14 is then designed to control the metering device 8 in terms of its output when the measured pressure value is below a reference value, so that the metering device increases its output. In addition or as an alternative to this, the control device 14 is designed to control the drive device 16 in relation to the rotational speed of the central screw 20 in such a way that the drive device increases its rotational speed. In addition or as an alternative to this, the control device 14 is designed to control the melt pump 4 in relation to the pump rotational speed in such a way that the melt pump reduces its rotational speed. This achieves that the pressure measured by the at least one pressure sensor 30 approximately reaches a predetermined reference value (the deviation is preferably less than 10%).

[0065] Additionally or alternatively, the control device 14 is also configured to control the metering device 8 in terms of its output in the event that the measured pressure value is above a reference value, so that the metering device reduces its output. Additionally or alternatively, the control device 14 is configured to control the drive device 16 with respect to the rotational speed of the central screw 20 in such a way that the drive device reduces the rotational speed of the central screw. Additionally or alternatively, the control device 14 is configured to control the melt pump 4 with respect to the pump rotational speed in such a way that the melt pump increases its rotational speed. This achieves that the pressure measured by the at least one pressure sensor 30 approximately reaches a predetermined reference value (preferably with a deviation of less than 10%).

[0066] As in Figure 2 As shown in FIG. 1 , there may be a plurality of further pressure sensors 31 which are arranged on other roller cylinders 3. 1 , ..., 3 n-1 On or arranged on other roller cylinders 3 1 , ..., 3 n-1 and is configured to measure the pressure in the planetary roller extruder 3. The control device 14 is configured to control the drive device 16 with respect to the rotational speed of the central screw 20 in such a way that the drive device reduces the rotational speed of the central screw and / or to control the melt pump 4 with respect to the pump rotational speed in such a way that the melt pump increases its rotational speed, if the pressure fluctuation of the pressure value measured by the at least one pressure sensor 30 or at least one of the plurality of additional pressure sensors 31 is above a threshold value. Because high pressure fluctuations often indicate insufficient homogenization due to too short a residence time of the plastic melt 2 in the planetary roller extruder 3. In addition, when the filling is too small, pressure surges may occur due to partially filled areas and wave-like discharges on blocked areas (for example, the dispersion ring 26).

[0067] The main influence on the residence time of the plastic melt 2 in the planetary roller extruder 3 is not only the accumulation of the plastic melt 2 due to the pump pre-pressure, but also the rotation speed of the planetary roller extruder 3 at a certain output. At the same output, the faster the central screw 20 rotates, the smaller the unit output and therefore the shorter the residence time. This is accompanied by an increase in shear and therefore an increase in material temperature.

[0068] The lower the rotational speed of the planetary roller extruder 3 is, while the output remains constant, the higher the specific output and thus the residence time is. This is accompanied by a reduction in shear and thus a reduction in material temperature.

[0069] According to the recipe and the permissible material temperature, the optimized operating point can be set.

[0070] It is important to achieve good homogenization at low material temperatures and low pressure fluctuations. High pressure fluctuations usually indicate inhomogeneities in the plastic melt 2. Pressure fluctuations can also occur if the specific output of the planetary roller extruder 3 is too low or too high. In the case of too low a specific output, pressure surges can occur in partially filled areas due to wave-like discharges at blocked areas such as dispersion rings. In the case of too high a specific output, the shear introduced into the plastic melt 2 is not sufficient to produce a homogeneous plastic melt 2.

[0071] Reference Figure 2 , 3 As can be seen from Figures 4 and 5, the central screw 20 is completely penetrated by at least one fluid channel 40a along its length. Figure 4 A fluid channel 40a is shown in FIG. Figure 2 and Figure 3 There are two fluid channels 40a, 40b. Figure 3 In the embodiment, one fluid channel 40a is used as a forward channel and the other fluid channel 40b is used as a return channel. In addition, a first pump device 41 and a first temperature control device 42 are provided (see Figure 2 ), the first pump device and the first temperature control device are configured to control the temperature of a fluid, in particular a fluid in the form of hot oil or water, to a certain temperature and guide it through the at least one fluid channel 40a. As a result, the plastic melt 2 can be controlled to a certain temperature. The central screw 20 includes corresponding interfaces or inlets / outlets for the fluid channel 40a or the fluid channels 40a, 40b, which are arranged on the same or different ends of the central screw 20.

[0072] In roller cylinder 3 1 , ..., 3 n Each roller cylinder 3 1 , ..., 3 n Includes at least one temperature adjustment channel 45a (see Figure 2 The second pump device 50 and the second temperature control device 51 are provided and configured to control the temperature of the fluid to a certain temperature and guide the fluid through the corresponding roller cylinder 3. 1 , ..., 3 n The at least one temperature control channel 45a is provided so as to 1 , ..., 3 n The internal plastic melt 2 is tempered to a certain temperature. Roller cylinder 3 1 , ..., 3 n The at least one temperature control channel 45a of the first roller cylinder 3 is separated from one another (not flowed through by the same fluid) and can therefore be temperature controlled differently, wherein the first roller cylinder 3 1The temperature of the fluid in the nth roller cylinder 3 is ideally higher than n The temperature of the fluid in the Figure 3 In the figure, only the temperature control channels 45a are shown by way of example. These temperature control channels are of course not openings from which the plastic melt 2 can be discharged.

[0073] Preferably, the temperature of the fluid guided through the central screw 20 is accurately set to 170°C (deviation ≤±10°C or ≤±5°C). However, in general, the temperature should be higher than 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C or higher than 200°C, but preferably lower than 205°C, 195°C, 185°C, 175°C, 165°C, 155°C, 145°C or lower than 135°C.

[0074] On the first roller cylinder 3 1 In the embodiment of the present invention, the temperature is preferably also set to 170°C (deviation ≤±10°C, ≤±5°C). However, generally, the temperature should be higher than 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C or higher than 200°C, but preferably lower than 205°C, 195°C, 185°C, 175°C, 165°C, 155°C, 145°C, 135°C, 125°C, 115°C, 105°C, 95°C or lower than 85°C.

[0075] On the second and third roller cylinders 3 2 , 3 3 In the embodiment of the present invention, the temperature is preferably accurately set to 160°C (deviation ≤±10°C or ≤±5°C). However, generally the temperature should be higher than 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, or higher than 170°C, but preferably lower than 175°C, 165°C, 155°C, 145°C, 135°C, 125°C, 115°C, or lower than 105°C.

[0076] In the fourth to sixth and preferably nth roller cylinder 3 4 , ..., 3 n In the embodiment of the present invention, the temperature is preferably set to 130°C (deviation ≤±10°C or ≤±5°C). However, the temperature should generally be higher than 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, or higher than 170°C, but preferably lower than 175°C, 165°C, 155°C, 145°C, 135°C, 125°C, 115°C, or lower than 105°C.

[0077] By means of these temperature settings, homogeneity, pressure fluctuations and the nozzle strip can be kept optimized. 1, ..., 3 n The possibility of temperature control can also positively influence the temperature and homogeneity of the material.

[0078] exist Figure 3 It is shown that one, more or all roller cylinders 3 1 , ..., 3 n The at least one temperature control channel 45a and the at least one temperature control channel 45b are located in the corresponding roller cylinder 3. 1 , ..., 3 n The inside of the corresponding roller cylinder 3 1 , ..., 3 n The second pump device 50 and the second temperature control device 51 are also configured to control the fluid to a certain temperature and guide the fluid through the corresponding roller cylinder 3. 1 , ..., 3 n At least one further temperature control channel 45b is provided in order to thereby control the temperature of the plastic melt 2 to a certain temperature. 1 , ..., 3 n The at least one temperature control channel 45a and the at least one further temperature control channel 45b are separated from each other and the corresponding fluids can be temperature controlled differently in the temperature control channels 45a, 45b. This allows very precise temperature settings. The plastic melt 2 is of course not in contact with the fluids. The temperature control channels 45a, 45b are located in the Figure 3 It is only clearly drawn for better clarity. No discharge of the plastic melt 2 from the temperature control channels 45a, 45b occurs.

[0079] For this purpose, preferably a plurality of temperature sensors 35 are used, which are arranged on different roller cylinders 3. 1 , ..., 3 n or arranged on different roller cylinders 3 1 , ..., 3 n The temperature sensor 35 is configured to measure the temperature of the plastic melt 2 at different positions in the planetary roller extruder 3. The material temperature of the plastic melt 2 or the roller cylinder 3 can be measured by the temperature sensor 35. 1 , ..., 3 n Steel temperature. When roller cylinder 3 1 , ..., 3 n When the temperature of the material deviates from the set temperature, only the temperature control needs to be adjusted. If the actual material temperature exceeds the permissible material temperature, measures must be taken to cool the material temperature before it is discharged from the wide slot nozzle 5 or the flushing valve, such as stopping the heat transport through the temperature control device (for example, in the melt pipeline, melt filter and / or wide slot nozzle 5), or stopping the planetary roller extruder 3.

[0080] The control device 14 is configured to control the second pump device 50 and the second temperature control device 51 in such a way that the second pump device and the second temperature control device pump faster and / or further cool the roller cylinder 3 when the temperature value of one or more temperature sensors of the temperature sensors 35 exceeds the temperature reference value. 1 , ..., 3 n The fluid in the roller cylinder is provided with a temperature sensor 35, the temperature value of which exceeds the temperature reference value, so as to cool the plastic melt 2. The flow through the second pump device 50 is preferably kept constant. Only the temperature of the fluid pumped through the second pump device changes. In addition or alternatively, the control device 14 is configured to stop the planetary roller extruder 3.

[0081] In addition, supplementally or alternatively, the control device 14 is configured to control the second pump device 50 and the second temperature control device 51 in such a way that the second pump device and the second temperature control device pump and / or heat the roller cylinder 3 more slowly when the temperature value of one or more temperature sensors of the temperature sensors 35 is lower than the temperature reference value. 1 , ..., 3 n The temperature sensor 35 is arranged on the roller cylinder, and the temperature value of the temperature sensor is lower than the temperature reference value, so as to heat the plastic melt 2. In this way, a very targeted temperature regulation can be achieved.

[0082] In at least one fluid channel 40a leading to the central threaded spindle 20 or in the roller cylinder 3 1 , ..., 3 n Hot oil with a temperature of up to 300° C. can be pumped into the temperature control channel 45 a or 45 b.

[0083] The invention is not limited to the described exemplary embodiments. Within the scope of the invention, all described and / or illustrated features can be combined with one another as desired.

Claims

1. A device (1) for producing a plastic melt (2) for porous membranes, the device having the following characteristics: The device has a planetary roller extruder (3) for producing a flowable plastic melt (2) from a thermoplastic; - a planetary roller extruder (3) having a filling opening (3a) and a discharge side (3b) for discharging the plastic melt (2); It is characterized by the following features: - the device is provided with a melt pump (4); The outlet side (3b) of the planetary roller extruder (3) is connected to the downstream inlet side (4a) of the melt pump (4) for further conveying the plastic melt (2); - The connection is constructed relative to the ambient atmosphere a) a shielded pressure channel; or b) a shielded pressure line (6); and the planetary roller extruder (3) and the melt pump (4) are designed and / or can be driven in such a way that the plastic melt (2) is available for processing or can be delivered under pressure on the inlet side (4a) of the melt pump (4), - There are no air openings in the area from the filling opening (3a) of the planetary roller extruder (3) to the inlet side (4a) of the melt pump (4), so that the air entrained in the plastic melt (2) is squeezed out of the plastic melt when the pressure of the plastic melt (2) builds up and is pressed back in the direction of the filling opening (3a) and is only degassed from the planetary roller extruder (3) at the filling opening.

2. The device (1) according to claim 1, characterized by the following features: The pressure is greater than 4 bar, at which the plastic melt ( 2 ) is waiting to be processed or can be delivered on the inlet side ( 4 a ) of the melt pump ( 4 ).

3. The device (1) according to claim 1 or 2, characterized by the following features: - In order to increase the pressure, the melt pump (4) is designed to reduce its pump speed so that the plastic melt (2) is blocked and accumulated from the inlet side (4a) of the melt pump (4) in the direction of the outlet side (3b) of the planetary roller extruder (3), and the plastic melt (2) is waiting to be processed or can be delivered at the inlet side (4a) of the melt pump (4) under the pressure, wherein a continuous material flow of other plastic melt (2) counteracts the blockage, resulting in an increase in the pressure.

4. The device (1) according to claim 1 or 2, characterized by the following features: The filling opening (3a) is provided as a common filling opening (3a) for the polymer and for the filler.

5. The device (1) according to claim 4, characterized in that The following features: - The polymer is a powdered polymer.

6. The device (1) according to claim 4, characterized by the following features: - The filler is a filler in the form of a liquid component.

7. The device (1) according to claim 4, characterized by the following features: - Applying a nitrogen atmosphere to the filling opening (3a).

8. The device (1) according to claim 1 or 2, characterized by the following features: - a drive device (16) is provided for driving the planetary roller extruder (3); - the planetary roller extruder (3) comprises n roller cylinders and a toothed central screw (20), wherein n≥1; The n roller cylinders are arranged adjacent to one another along their longitudinal axes and are fastened to one another and sealed to one another; - Each roller cylinder comprises an internally toothed cylinder sleeve (21) and m toothed planetary screws (22), wherein m≥3, and is penetrated by a toothed central screw (20); - the central screw (20) and the m toothed planetary screws (22) are arranged in the cylinder sleeve (21) of the corresponding roller cylinder, wherein each of the planetary screws (22) is arranged between the central screw (20) and the cylinder sleeve (21); - the central screw (20) can be driven by a drive device (16), wherein, on the one hand, the central screw (20) and the planetary screws (22) mesh, and on the other hand, the planetary screws (22) mesh with the internally toothed cylinder sleeve (21), so that the m toothed planetary screws (22) roll on the central screw (20) and the cylinder sleeve (21) by the rotation of the central screw (20); The filling opening (3a) is arranged in the first roller cylinder (31) and the discharge side (3b) is arranged in the nth roller cylinder (3 n )middle.

9. The device (1) according to claim 8, characterized by the following features: - the n roller cylinders (31, ..., 3 n ) are twisted together.

10. The device (1) according to claim 8, characterized by the following features: The toothing of the central screw (20), the cylinder sleeve (21) and the planetary screw (22) is a 45° bevel toothing, which allows the plastic melt (2) to flow forward and can be pressed out at the same time.

11. The device (1) according to claim 8, characterized by the following features: - provided with a metering device (8); - The metering device (8) comprises: a) at least one metering device (9) for gravimetric determination of the polymer; and b) a metering pump device (10) having at least one metering pump and at least one injection device (11) for the liquid component; the metering device (8) is configured to meter the polymer and the liquid component and: a) delivering the polymer and the liquid component directly via a filling opening (3a) into a first roller cylinder (31), where the polymer and the liquid component can be mixed with one another; or b) providing the polymer and the liquid component to a side feeder (7) having one or two conveying screws, wherein the polymer and the liquid component are mixed in the side feeder, wherein the conveying screws are configured to discharge the mixture through the filling opening (3a) into a first roller cylinder (31).

12. The device (1) according to claim 11, characterized by the following features: a first storage container (13a) and a second storage container (13b) are provided for the first and second liquid components; The metering pump device (10) is connected or connectable to a first storage container (13a) and / or to a second storage container (13b), so that the first liquid component and / or the second liquid component can be conveyed to the filling opening (3a); or a first storage container (13a) and a second storage container (13b) are provided for the first and second liquid components; The metering pump device (10) comprises a first metering pump (10a) and a second metering pump (10b), wherein the first metering pump (10a) is connected or connectable to a first storage container (13a), and the second metering pump (10b) is connected or connectable to a second storage container (13b), so that the first liquid component and / or the second liquid component can be delivered to the filling opening (3a).

13. The device (1) according to claim 11 or 12, characterized by the following features: The metering device (8) comprises one or more further injection devices (11), wherein the one or more further injection devices (11) are respectively arranged along the planetary roller extruder (3) and are configured to inject additional metered quantities of the liquid component into the planetary roller extruder (3).

14. The device (1) according to claim 13, characterized by the following features: The one or more additional injection devices (11) are arranged along the planetary roller extruder (3) from one roller cylinder (31, ..., 3 n ) to another adjacent roller cylinder (31, ..., 3 n ) in the transition region.

15. The device (1) according to claim 11 or 12, characterized by the following features: The metering device (8) is configured to set the ratio between the amount of polymer and the amount of liquid component supplied to the planetary roller extruder (3), wherein: 80 to 50 parts by weight of the liquid component can be added to 20 to 50 parts by weight of the polymer.

16. The device (1) according to claim 11 or 12, characterized by the following features: The metering device (8) is configured to set the ratio between the amount of polymer and the amount of liquid component supplied to the planetary roller extruder (3), wherein: 75 to 55 parts by weight of the liquid component can be added to 25 to 45 parts by weight of the polymer.

17. The device (1) according to claim 11 or 12, characterized by the following features: The metering device (8) is configured to set the ratio between the amount of polymer and the amount of liquid component supplied to the planetary roller extruder (3), wherein: 70 to 60 parts by weight of the liquid component can be added to 30 to 40 parts by weight of the polymer.

18. The device (1) according to claim 11 or 12, characterized by the following features: The device is provided with at least one pressure sensor, which is arranged at the nth roller cylinder (3 n ) or arranged on the nth roller cylinder (3 n ) between the inlet side (4a) of the melt pump (4) and is configured to measure the pressure of the plastic melt (2); The device is provided with a control device (14) which is configured to a) When it is lower than the reference value: i) controlling the metering device (8) in such a way as to control the output of the metering device, causing the metering device to increase its output; and / or ii) with respect to the rotational speed of the central screw (20), the drive device (16) is controlled in such a way that the drive device increases the rotational speed of the central screw; and / or iii) with regard to the pump speed, the melt pump (4) is controlled in such a way that the melt pump reduces its speed; So that the pressure measured by the at least one pressure sensor reaches a predetermined reference value; and / or b) When higher than the reference value: i) controlling the metering device (8) in such a way as to control the output of the metering device, causing the metering device to reduce its output; and / or ii) with respect to the rotational speed of the central screw (20), the drive device (16) is controlled in such a way that the drive device reduces the rotational speed of the central screw; and / or iii) with regard to the pump speed, the melt pump (4) is controlled in such a way that the melt pump increases its speed; Thereby, the pressure measured by the at least one pressure sensor reaches a predetermined reference value.

19. The device (1) according to claim 18, characterized by the following features: The device is provided with a plurality of further pressure sensors, which are arranged on the further roller cylinders or between the further roller cylinders and are designed to measure the pressure of the plastic melt (2) in the planetary roller extruder (3); The control device (14) is configured to: i) controlling the drive device (16) with respect to the rotational speed of the central screw (20) in such a way that the drive device reduces the rotational speed of the central screw; and / or ii) With regard to the pump speed, the melt pump (4) is controlled in such a way that it increases its speed.

20. The device (1) according to claim 8, characterized by the following features: - The central screw (20): a) is constructed in one piece and extends through all n roller cylinders; or b) comprises a plurality of individual central spindle segments, which are connected to one another along their longitudinal axes in a rotationally fixed manner to form the central spindle (20).

21. The device (1) according to claim 8, characterized by the following features: - the planetary screw (22) in the partial roller cylinder is arranged only in the corresponding roller cylinder and does not extend from the roller cylinder into the adjacent roller cylinder; and / or The first two adjacent roller cylinders comprise a continuous planetary screw (22), which is arranged both in the first roller cylinder (31) and in the second roller cylinder (32).

22. The device (1) according to claim 8, characterized by the following features: - a toothed intermediate ring (25) is inserted between the first roller cylinder (31) and the second roller cylinder (32); The toothed intermediate ring (25) reflects the internal toothing of the cylinder sleeve (21).

23. The device (1) according to claim 8, characterized by the following features: - starting from at least the second roller cylinder, a dispersion ring (26) is arranged between two adjacent roller cylinders; - the dispersion ring (26) at the transition from the second roller cylinder (32) to the third roller cylinder (33) has a greater dispersion than that from the n-1th roller cylinder (3 n-1 ) to the nth roller cylinder (3 n ) a larger or smaller annular gap of the dispersion ring (26) at the transition between the two ends; or The dispersion ring (26) at the transition from the second roller cylinder (32) to the third roller cylinder (33) has the same n-1 ) to the nth roller cylinder (3 n ) at the transition point of the dispersion ring (26).

24. The device (1) according to claim 8, characterized by the following features: - the toothing of the central threaded spindle (20) is interrupted in the transition from one roller cylinder to an adjacent roller cylinder; and / or The toothing of the planetary screw (22) is interrupted multiple times in at least one roller cylinder, thereby increasing the cross-mixing in the corresponding roller cylinder.

25. The device (1) according to claim 8, characterized by the following features: - the central screw (20) is penetrated completely or along most of its length by at least one fluid channel (40a); The device is provided with a first pump device (41) and a first temperature control device (42), and the first pump device and the first temperature control device are configured to control the temperature of a fluid to a certain temperature and to guide the fluid through the at least one fluid channel (40a), so as to thereby control the temperature of the plastic melt (2) to a certain temperature.

26. The device (1) according to claim 8, characterized by the following features: - the roller cylinder comprises at least one temperature-regulating channel (45a); - the device is provided with a second pump device (50) and a second temperature control device (51), and the second pump device and the second temperature control device are configured to control the temperature of the fluid to a certain temperature and guide the fluid through the at least one temperature control channel (45a) of the corresponding roller cylinder, so as to thereby control the temperature of the plastic melt (2) to a certain temperature; The at least one temperature control channel (45a) of the roller cylinders is separated from one another and can be temperature-controlled differently, wherein the temperature of the fluid in the first roller cylinder (31) is higher or lower than that in the nth roller cylinder (3 n ) is the temperature of the fluid in .

27. The device (1) according to claim 26, characterized by the following features: - one or more roller cylinders comprise at least one additional temperature-regulating channel (45b); The at least one temperature control channel (45a) and the at least one further temperature control channel (45b) are arranged offset to one another inside the respective roller cylinder in the longitudinal direction of the respective roller cylinder and / or in the circumferential direction; - the second pump device (50) and the second temperature control device (51) are further configured to control the temperature of the fluid to a certain temperature and to guide the fluid through the at least one further temperature control channel (45b) of the corresponding roller cylinder in order to thereby control the temperature of the plastic melt (2) to a certain temperature; The at least one temperature control channel (45a) and the at least one further temperature control channel (45b) of the respective roller cylinder are separated from one another and the respective fluids can be temperature-controlled differently in the temperature control channels (45a, 45b).

28. The device (1) according to claim 26, characterized by the following features: The device is provided with a plurality of temperature sensors (35), which are arranged on different roller cylinders or between different roller cylinders and are configured to measure the temperature of the plastic melt (2) at different positions in the planetary roller extruder (3); The control device (14) is designed to, for a temperature value of one or more of the temperature sensors (35), a) in the event of exceeding a temperature reference value, the second pump device (50) and the second temperature control device (51) are controlled in such a way that they pump and / or cool the fluid in the roller cylinder on which a temperature sensor (35) is arranged, the temperature value of which exceeds the temperature reference value, in order to thereby cool the plastic melt (2); and / or b) When the temperature is below the temperature reference value, the second pump device (50) and the second temperature control device (51) are controlled so that they pump the fluid in the following roller cylinder more slowly and / or increase the temperature so as to heat the plastic melt (2) thereby, on which the following temperature sensor (35) is arranged, the temperature value of which is below the temperature reference value.

29. The device (1) according to claim 1 or 2, characterized by the following features: - the melt pump (4) can be electrically heated; or The melt pump (4) can be heated by means of thermal oil.

30. The device (1) according to claim 1 or 2, characterized by the following features: - the device is provided with a wide-slot nozzle (5), which is connected to the discharge side (4b) of the melt pump (4); A flushing valve and / or a melt filter is arranged between the outlet side (4b) of the melt pump (4) and the wide-slot nozzle (5).

31. The device (1) according to claim 30, characterized by the following features: The device is provided with a cooling roller (27), which is arranged below the wide-slot nozzle (5) so that the plastic melt (2) discharged from the wide-slot nozzle (5) hits the cooling roller (27).

32. Use of an apparatus (1) for producing a plastic melt (2) for a porous membrane, wherein: The device (1) is a device according to any one of claims 1 to 31, and the polymer and the liquid component are fed to the filling opening (3a).

33. The use according to claim 32, characterized by the following features: The plastic melt (2) is a plastic melt (2) for a thin film.

34. The use according to claim 32 or 33, characterized by the following features: - the liquid component consists of or comprises a solvent; and / or - The liquid component comprises hydrocarbons.

35. The use according to claim 32 or 33, characterized by the following features: - the liquid component consists of or comprises a solvent; and / or - The liquid component comprises one or more of the following media or consists of one or more of the following media: a) Paraffin oil; b) petroleum hydrocarbons; and / or c) White mineral oil.

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