KR850000531B1 - Apparatus for producing mixtures of thermoplastic synthetic resins & mineral or organic fillers - Google Patents

Abstract

In the apparatus for producing a mixture of thermoplastic synthetic resins and mineral or organic fillers, the apparatus is characterized by the following composition. The insulating material layer is laid on an inner surface, a stirring arm and wiper are attached and, in driving, the rotating upper axis is located. The insulated mixing cylinder connects with a cooling reactor and the mixing instrument. A vacuum pump is connected to the body and cover of the instrument, a conductive spike and a rotor are installed in the mixing instrument.

Description

Apparatus for the preparation of mixtures of heated plastic composites with mineral or organic fillers

1 is a schematic representation of an apparatus according to the invention in which a process of filling and mixing the components with friction is carried out.

2 is a schematic diagram of an apparatus of an embodiment of the present invention in which a process of filling and mixing the components in an electric field is performed.

3 is a schematic representation of the combined filling and mixing grid of the FIG. 2 device.

4 is a schematic representation of an apparatus according to the present invention for filling its components for a continuous process in an electric field.

5 is a cross-sectional view of a mixture piece produced by the device according to the invention with a plastic core and a filling cover.

6 is a partially enlarged view of the interface of the fragment of FIG.

7 is an enlarged partial view at the boundary of the fragment of FIG.

The present invention relates to a mixture preparation apparatus comprising a mixture of thermoplastic plastics and inorganic (mineral) or organic fillers, in particular initial materials in a vacuum or compressed state.

The purpose of mixing plastics with organic or inorganic fillers is first to obtain cheap raw materials and secondly to obtain the required properties.

If the mixture cannot be processed immediately, it must be transported and there is a difficulty in putting a homogeneous, homogenous, stable material in the non-mixed state into the mixing processor of the plastic and the filler. Moreover, as a raw material for the continuous process, the mixture needs some strength. For this reason, various devices have been tried in the past. In other words, by slightly lowering the heat treatment of the plastic organ to melt or soften the plastic.

In this process the plastic and filler components are mixed together by spinning, kneading, calcining or taking out. In order to form a large adhesion between the plastic and the filler, the pores of both components should be freed from moisture and air as much as possible. Otherwise, the VAN DER WAALS force that binds the two components increases as the distance between the molecular chain of the plastic and the filler decreases. If the anti-stick coating of air or moisture is removed, the bonding proceeds in a vacuum in a single or two screw blower where the material is transported, mixed and condensed. Therefore, a funnel with a degassing device must be used to add ingredients.

This problem is the basis for the production process of mixtures of plastics and fillers known from German Patent No. 2324189. According to this, the filler is strongly dried in advance in the vacuum and then withdraws moisture while mixing with the plastic under vacuum again. The treatment temperature during the mixing process must be controlled properly and the plastic particles introduced in powder form become solid at the surface, so that the particles of the filler are sintered with them, and the mass thus formed is mixed in a later step.

The disadvantages of this process are the complexity and cost of the filler drying and sintering or gelling operations, and little effect on the degree of adhesion between the filler particles and the plastic model. Homogeneity was due to failure to meet ordinary conditions. Moreover, color dyes must be added before mixing. In another process (German Patent No. 2332583), plastic and filler are added together to form a constant dough to make the required mixture.

Constant kneading heat during the kneading operation rises due to the externally supplied heat supply, melting the plastic particles and mixing them with the filler particles. This process continues until the filler is actually used all at mixing idle, leaving unbounded and unmixed fillers or polymer particles being used to the extent necessary by melting.

Depending on the components used, the process must be repeated several times. Other known processes that may fall within the scope of the "heat treatment method" according to the physics action have the drawback that the other equipment required is expensive, expensive to operate and limited in processing capability. Moreover, the prepared mixture was not uniform in nature, and the filler ratio of the individual fine particles was varied.

This results in a qualitative degradation in the mixture or its preparation because the adhesion between the plastic matrix and the filler particles becomes inadequate. Since the adhesive force decreases as the proportion of the filler increases, the mixture of the plastic and the filler tends to break easily or to have an excessively high modulus of elasticity. Obviously this problem can be solved or improved at least with the addition of so-called separate adhesives, but the process is complicated and expensive and is used only for the production of certain products.

It is an object of the present invention to provide a device for producing a homogeneous mixture of plastics and fillers, in which the mixture is homogeneous and well mixed even in powder form and can be commercialized without complex granulation processes. Furthermore, the material produced by the device of the present invention is robust and usually does not have a brittle property to follow, and has the same degree of adhesion as pure plastic material not found in the mixtures prepared according to the device described above.

Finally, since the device according to the invention is cheaper than the device according to the prior art, the price reduction resulting from the saving of raw materials is not consumed at high process costs.

Another object of the present invention is to provide a suitable apparatus for carrying out the process of the invention. According to one aspect of the invention, there is provided an apparatus for preparing a mixture by mixing a thermoplastic plastic with one or more inorganic (mineral) or organic fillers by mixing under vacuum and equal pressure, the apparatus being or during mixing with the plastic. Previously, the filler was charged either electrically or electrostatically.

The filling process in the manufacturing process of the present invention consists of a strong friction on the surface and the inner part of the reaction apparatus which is a friction action and filling between the filler particles and the plastic particles, in this way the heat of friction and thus the electrical and electrostatic charging is achieved. In the process of the present invention, the filling process takes place in the electric field before mixing the plastic and the filler. In this case the input material during the filling process is constantly stirred to maintain a uniform distribution of filling.

The present invention also provides an apparatus for carrying out the process, which comprises a cooling vacuum vessel in which the mixing apparatus is introduced, which also introduces the initial material into the vacuum vessel, releases the final mixture from the vessel and evacuates the vessel. Conical and slide valves are also included, and the apparatus includes a filling and mixing reaction device coupled as a device which creates a strong friction between the contents of the filling and mixing reaction device, which is connected to a cooling intermediate tank and filled and cooled in the cooling reaction device. It is connected to the pipeline returning to the mixing reactor.

The invention also consists of a vacuum vessel equipped with a mixing device, an accessory for supplying the initial material to the vessel, removing the final mixture and keeping the vessel in vacuum, and two or more filling reactors connected to the vacuum vessel.

The present invention also provides a material in which fine thermoplastics and powders are combined with fine organic or inorganic fillers by electrostatic forces or Van Der Waals Forces.

In the process according to the invention the filler is charged either electrically or electrostatically. Depending on the type of filler, this filling lasts for many months. Thus, during the mixing process, pretreatment of the filler is possible and, if necessary, stored as a mixture for a certain period of time. During the mixing of the plastic and the filler, the filler is separated by friction so that the plastic raw material can be filled with the opposite polarity to the filler. Certainly, by combining plastics and fillers according to their relative positions in the electrostatic field, the plastics are first charged and therefore the fillers are filled in the opposite polarity.

As a result of the mutually opposite polarization of the two components, a strong adhesive layer of filler particles is formed around all the kernels of the plastic during the mixing process. Compared to the process described in the prior art, the particles of filler are not solidified or scintilled on the soft surface of the plastic particles. This is evidenced by the following facts:

That is, when the mixture of plastic and filler is dispersed in water, the surface layer of the filler separates from the plastic granules. Because there is no electrostatic bond in the water. Electron microscopy shows that the surface was virtually intact in subsequent experiments of the first exposed granules of plastic powder. The shell thickness of the filler is determined according to the required proportion of the filler.

The total amount of filler added is incorporated into the filler shell and does not form lumps or pieces separated from the plastic. Therefore, it is not influenced by the mechanical force normally generated by this method, that is, extrusion force, impact force, shear force or friction force. Moreover, the shell formation of the filler frees the flow of powder and makes the process more desirable.

As such, the mixture of plastics and fillers resists unmixing even when still in powder form. The principle is that if the buyer desires, the mixture is granulated form or taken directly out of the process to form the final product.

A particular advantage over the process described in German patent 2323389 is that the final product can be colored at the final stage and is particularly advantageous for fibers made from the raw materials according to the invention. In addition, according to the improved material properties of the filled plastic, the adhesive force between the plastic and the filler caused by the global filling of the components cannot be obtained from the mixture of the plastic and the filler prepared according to the conventional method.

When comparing the mechanical properties of the polypropyranene mixture containing 40% by weight of talc (滑石 Talc) prepared according to the present invention and the standard commercial polypropylan mixture containing 40% by weight of talc as follows.

In particular, the product produced according to the present invention has a low modulus of elasticity, and the highest tensile strength and impact strength are improved.

Various methods may be used to carry out the process according to the present invention, but will be understood more specifically in the following examples. When explaining an embodiment for the process according to the accompanying drawings and the method of the embodiment,

Example 1

(A) Filler containing water within 3% by weight, for example, 20 kg of Hobun Chalk, Talc, Kaolin or Mica at a pressure of 10 millibars in a high speed mixer. Mix in. This creates a strong friction of the particles of the filler against the surface and inside of the reaction apparatus. Thus, the particles are electrically charged, the arc is negatively charged and the talc, kaolin and mica are positively charged by the 1-10KV voltage.

This filling effect is stable if mixed for a short time (about 0.5 seconds) at a maximum temperature of about 200 ° C., which can be obtained by frictional heat or by heating separately. Fillers filled in this way must be cooled again. The electrostatically charged filler is then placed in a vacuumed high speed mixer with the required amount of plastic, 20-30 kg of polyethyllan, polypropylan or other powdered thermoplastic plastic.

They are mixed thoroughly under pressure within about 1000 Pascals, but the temperature should not exceed the maximum temperature characteristic indicative of the degree of friction and the degree of filling separation of the filler and plastic. This maximum temperature is below the softening temperature of the plastic and depends on the component ratio and the mixing ratio of the plastic and the filler as shown in the following table.

[table]

The mixture of plastics and fillers thus prepared is either stored in powder form or granulated form in the drawer if necessary or otherwise directly processed to produce the final product. The granulation and its process are carried out under vacuum so that the strong wetting of the filler by the thermoplastic is not hindered by air-containing layers in the cavities or indentations of the rough surfaces of the shells or droplets and thus the adhesion is advantageous. The attraction due to electrical charging gives good properties to the filled thermoplastics, and particularly good impact strength even at low elastic modulus.

(B) The process of this embodiment is possible by using the apparatus shown in FIG. The apparatus comprises a charging and mixing reaction device 10 having two feed funnels 11 and 12. The reactor 10 for filling and mixing has two outlets 13 and 14 at the bottom which are connected to the cooling intermediate tank 15 and the piping 16 is where the cooling reactor 17 is located. Is connected to. In the cooling reaction device 17, the pipe 18 exits and is recovered to the reactor 10 for charging and mixing, which is coupled to the cooling 18. The reactor 10 for filling and mixing consists of a body 19 and a lid 20, the body 19 being electrically connected to the lid 20 and the layer 21 of Atlanto with polytetsfluoro. It is insulated. In order to make the required vacuum, the reactor 10 is connected to the vacuum pump 22 via the lid 20, and the pressure gauge 23 is blown into the lid 20. The lid 20 may be connected to the high voltage generator 24 to supply a voltage in the range of 0-10 KV. The body 19 is grounded to the mixing device 26 via the ground line 25 and the temperature sensor 28 and the quantum meter 29 are attached, and the cooling coil 30 reacts in a ring shape. Arranged around the device body 19, the ground of the body 19 and the mixing device 26 is interrupted by a switch 27.

The supply cone funnels 11 and 12 are connected to the vacuum pump 22, and each of them is connected to the pressure gauges 31 and 32. The two funnels 11 and 12 are connected to the reactor 10 via vacuum shields 33 and 34. At the outlet 10 of the charging and mixing reactor 10, the pipe 35 is connected to a cooling intermediate tank 15 to which a pressure gauge 37 and a vacuum pump 36 are connected. This intermediate tank 15 is surrounded by an annular cooling pipe 38 on the outside. The cooling intermediate tank 15 and the cooling reaction device 17 are connected to the pipe 16. The cooling reactor 17 is composed of a body 40 to which a lid 41 is attached, and the body 40 has a non-conductive layer 42 of ethyllan in polytetrafluoro. The cooling pipe 43 is disposed annularly around the outside of the cooling reactor 40. There is a shaft 44 to which three stirring arms 45 are attached, and there is a wiper 46 between each stirring arms.

(C) The preparation of the plastic and filler mixing process according to the process described in the example proceeds as follows according to the apparatus of FIG. 30 kg of a material such as talc is supplied to the reactor 10 for filling and mixing through an empty funnel 11 and a product slide valve 33. In the reactor 10, the filler is thoroughly mixed by the high speed stirrer 26 so that the filler is heated and electrically charged. Charging is continually sensed by temperature sensor 28 and quantometer 29. The lid 20 is alternately filled by the high pressure generator 24 in a polarity opposite to that of the filler so that the filled layer of filler does not get caught in the lid 20 of the reactor 10. The temperature is also raised to 70-80 ° C.

The body 19 and the stirrer 26 of the reaction device, on the other hand, are grounded and, if necessary, are grounded with a filling work switch 27 to maintain a constant potential. When the filler is sufficiently filled, the filler is transferred to the cooling intermediate tank 15 via the outlet 14 and the pipe 35. Here, the filler is cooled with water flowing through the cooling coil 38 before the piping 16 is transferred to the cooling reactor 17. In the above cooling process, the reactor 10 for charging and mixing is cooled with cooling water flowing through the cooling coil 30, and a new filler in the kiln may be introduced into the reactor 10 through the funnel 11. The filling of the filler here proceeds in the same manner as above. Since the cooling reactor 17 is four times the volume of the reactor 10 for charging and mixing, the filler 4 kiln can be cooled and stored. This is convenient because the filling time of the filler is shorter than the mixing and cooling time of the plastic and filler.

Once the cooling reactor 17 is saturated, the filler of the first kiln at the bottom is cooled so that a portion can be supplied into the reactor 10 for filling and mixing through the pipe 18 and the funnel 11. At the same time an appropriate amount of plastic is supplied to the reactor 10 through the funnel 12. Here the plastic and the filler are strongly mixed and the electrical charging of the filler proceeds in the same way. The temperature at this time is continuously detected by the temperature sensor 28. Once sufficient fill separation occurs during the mixing process, mixing is stopped. The final powder mixture is then discharged and packaged via outlet 13 or passed to a granule taker or other process.

Example 2

(A) As a modification of the process described in Example 1, the filler or plastic particles may be exposed by being exposed to a strong electric field. This requires high voltage to be applied to the outer wall of the reactor and the stirring period. It is especially good to make a stirrer in the form of a grid with spikes. This is because, during so-called point discharge, even a low voltage can partially make a strong electric field. Therefore, this device is a device having an electrically neutral solid component acting as an insulator. When a negative voltage is applied to the spikes in the stirrer grid, the spikes emit free electrons obtained by the molecules of the filler or plastic.

When the particle component is negatively charged, electrons continue to be generated. Thus, displacement of the charge transport grid towards the outer wall of the reactor occurs until the particles themselves become charge carriers and all particles are charged to the required level. The discharge of particles of the opposite electrode, which is the outer wall, is prevented due to the electrical insulation layer of the inner wall of the vessel of the reactor.

If the particles are charged with a positive charge (+), the polarity of the stirrer grid and the outer wall must be opposite to that. The strong electric field of the grid spikes as the anode (+) releases electrons from the molecules of the particle component and causes electron shortage. That is, it results in charging of both charges. In all these cases, the amount of charge charged is detected by the voltage level and the process time during the work process.

The material is stirred constantly and slowly with continuous rotation of the stirrer grid for even distribution of charge. After filling, the material components are sent to a mixing reactor, mixed in the manner described in Example 1 and transferred for each of the following uses. Compared to the electrical charging in a high speed mixer as described in Example 1, the charging method in the electric field described in this embodiment is advantageous because it does not require cooling of the filler after the charging process. As a result, there is no need for a re-reduction device to cool the raw material and place it in the mixing reactor. Furthermore, the filling process does not need to select the filling amount and polarity and adjust the suction force generated during the mixing of the plastic and the filler, so that the coloring of the plastic kernel is good.

(B) The filling of the components in the electric field is valid in the apparatus shown in Figures 2 and 3.

The two reactors 50 and 51 of FIG. 2 are of the same structure and are installed on the vacuum vessel 49 for electric charging (only one of the two reactors will be described). The reactor 50 is vacuumed by the vacuum pump 52, and may detect the vacuum state by the pressure gauge 53. The reactor 50 is composed of a body 54 and a lid 55 electrically insulated from the body. The reactor body 54 has an electrical insulation layer 56 embedded therein. There is a stirring cylinder (57) inside the vacuum and insulated reactor (55), which consists of an electrically insulating material and a dielectric core (Comductiv Core) 58. The stirring cylinder 57 occupies about half in the body 54.

As shown in FIG. 3, the dielectric core 58 of the stirring cylinder 57 is connected to the stirrer 59 in the form of a grid 59a of two arms, with each grid surface approximately 30 in vertical. ° tilted about The intersection of the remote Java (Lattice Bar) of individual to form a grid (59a) is mounted on a dielectric core placed within a short spike that the grid plate (59 _b) of the dielectric material. This spike 59 _b is at the top of the grid 59 _{a which} is inclined by about 30 ° and points in the direction of rotation of the grid. A voltage of 0-100 KV is applied to the outer wall 60 of the dielectric material of the reactor body 54 and the dielectric core 58. This voltage is obtained by the adjustable high pressure generator 61 and is transmitted to the rotating dielectric core 58 by the brush electrode 62. The reactor 50 has a vacuum inlet 63 and an outlet 64, which are connected to the vacuum slide valve 33 of the vacuum vessel 49. The vacuum vessel 49 has the same structure as the mixing reactor in the first embodiment. As described above, the cooling intermediate tank and the cooling reactor are not necessary and therefore not used here.

(C) In the apparatus described above, the process according to this embodiment is as follows.

The filling amount of the spare part is supplied to the reactor 50 through the vacuum material inlet 63. In this reactor, the filler is rotated while stirring is continued by the stirrer (59). A contact pressure of 80 KV obtained from the high pressure generator 61 is applied between the outer wall 60 of the dielectric material and the stirrer 59. The polarity of the two dielectric components of the stirrer and the outer wall is determined by the required filling polarity of the filler. The filler continues to rotate with the stirrer in a vacuum reactor until all particles have the required amount of charge.

The filler is then transferred to the vacuum vessel 49 via the outlet 64 and the vacuum slide valve 33. At the same time a uniform amount of plastic is introduced via the slide valve 34 in the vacuum vessel 49, and the plastic material is also electrically filled. In the vacuum vessel 49, charge separation takes place by the high-speed mixing of the two components by the method described in Example 1 to form a composite required for electrostatic attraction.

Example 3

(A) As described in Examples 1 and 2, only the required mixture of plastics and fillers are produced discontinuously, one by one, and the apparatus of FIG. 4 is designed for the continuation of the manufacturing process. Since the filling of the component is carried out in the electric field by the method described in Example 2, there is no need for cooling or intermediate storage of the component.

(B) Therefore, the apparatus for continuously preparing the plastic and filler mixture according to FIG. 4 is a conical mixing vessel 65 having two filling reactors 50 and 51 corresponding to the reactor described in Example 2. Since the components filled therein are supplied into the conical mixing container 65 via the input pipes 66 and 67. A vacuum pump 68 is connected to this mixing vessel 65 to create the required vacuum, while the pressure in the mixing vessel is detected by a pressure gauge 69. This mixing container 65 is configured like a cylinder 70 in which a funnel-shaped cone 71 is formed. The inner wall of the cylinder portion 70 of the conical mixing vessel 65 has a groove 72 that is spirally inclined.

In the vessel 65, three rota 74 are arranged perpendicular to the spherical axis 73, one of which is small in diameter and located at the apex of the cone 71, the other two of which are large in diameter. Is under the cylinder 70 of the mixing vessel 65. The direction of rotation of the rotor 74 is selected such that the material is sent upwards as a tilted spiral. At the bottom of the cone 71 there is an outlet 75 which is connected to the mixing device 76 of plastic and filler.

(C) The process of this embodiment is shown in the apparatus of FIG.

The components charged with opposite polarity in the reactors 50 and 51 are sent to the mixing vessel 65 via the input tubes 66 and 67. While sent to the top, the two components, plastic and filler, mix well. The final mixture falls on the cone 71 as the feed is controlled at the speed of the rotor 74 and the supply of the components in the mixing vessel 65 during the process in which the material is conveyed upwards in the spiral groove and mixed. Here it is mixed into the rota 74 at the bottom of the cone and is transferred to the outlet 75 and continues to feed into the apparatus prepared for the subsequent process which continues under vacuum. The total delay time in the mixing vessel 65 should be at least 5 minutes.

5 is an enlarged photograph of a single particle 80 of a mixture of plastic and filler produced according to an embodiment of the present invention. In the photograph, the particles 80 are cut out in a cross section, and the shell of the filler 82 is opened and the plastic core 81 has a structure of the particles. In addition, the sharp separation line 83 of the shell period of the plastic core 81 and the filler 82 is clearly shown. As such, the particles of filler did not penetrate into the plastic core, the plastic core did not melt, and did not bind to the filler.

6 and 7 show two different magnification electron micrographs, which can be seen in more detail, showing the dividing line 83 between the shell of the filler 82 and the plastic core 81. There is no penetration of the plastic component 85 between the individual particles of the filler 84 which can be seen in the sintering or colliding process between the plastic raw material and the filler. As such, the attraction force due to the opposite polar charge causes the plastic and the filler to adhere completely.

Claims (1)

In the apparatus for preparing a thermoplastic plastic and inorganic or organic filler mixture, the non-conductive material layer 42 is laid on the inner surface, and the stirring arm 45 and the wiper 46 are attached to the upper side 44 which rotates during operation. ) it is embedded, and isolation of a conductive core 58, stirred connected to the machine (59) consisting of a vacuum pump 36 is connected to the cooling reactor 17 and the surface is 30 ° cancer grid (59 _a) inclined in the vertical The agitated cylinder 57 occupies half of the internal volume, the body 54 and the lid 55 on which the electric insulation layer 56 is laid on the inner surface are electrically insulated from each other and connected to the vacuum pump 52, Spikes 59 _b are installed, and the generated voltage of the voltage-adjustable high-pressure generator 61 is applied to the wall 60 and the conductive core 58 of the reactor and the outlet is connected to the vacuum vessel 49 by vacuum. Sloped groove with two filling reactors 50, 51 and outlet 75 and cylinder 70 It is formed inside the 72, the lower portion is composed of a cone 71, the mixing shaft 65 and the like installed in the center of the vertical drive shaft 73 in the center of the cone 71 and the rotor 70 at the end of the cylinder 70, etc. Apparatus for producing a mixture of a thermoplastic synthetic material and a mineral or organic filler material, characterized in that it is configured.

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