A method and system for producing ABS white plastic masterbatch

Abstract

The present invention discloses a method and system for producing ABS white plastic masterbatch, which comprises the following steps: (1) placing ABS raw material, color powder, dispersant and processing aid in a mixer according to a required proportion through a feeding device, and mixing and stirring them fully to obtain a mixture; (2) feeding the mixture into a twin-screw pelletizer for mixing, extruding and drawing; (3) arranging a filtering mechanism at the discharge port of the twin-screw pelletizer, wherein the filtering mechanism comprises a porous plate with a plurality of raw material through holes at the end surface, and a filter screen group arranged inside the porous plate, wherein the filter screen group comprises three layers of filter screens, wherein the filter screen located in the middle layer is a high-mesh filter screen, and the filter screens located on both sides are low-mesh filter screens; (4) cooling and drying the drawn mixture through a cooling water tank and air drying equipment, and then cutting and bagging the mixture to obtain an ABS white plastic masterbatch finished product or an ABS white plastic semi-finished product.

Description

Technical Field

[0001] The invention relates to the field of plastic masterbatch production and manufacturing, and in particular to an ABS white plastic production method and system. Background Art

[0002] In the production process of white plastic masterbatch, the production parameters that affect the color change mainly include the temperature, internal pressure, screw speed, feeding speed, current size, etc. of the screw extruder. The size of these parameters will cause the white plastic masterbatch produced to be blue or yellowish compared with the required color. Among them, when the temperature is lower than the required temperature for production, the white masterbatch will be blue, and when the temperature is higher than the required temperature for production, the white masterbatch will be yellowish; and the internal pressure will increase the internal temperature of the extruder. If the screw speed is too fast, the mixture will be heated unevenly and fail to reach the production temperature, resulting in the finished product being blue, and vice versa; if the feeding speed is too slow, the temperature of the mixture will be too high, while if it is too fast, the temperature of the mixture will be too low; if the current is too large, the mixture will heat up quickly, which may easily lead to uneven heating inside and outside the mixture, while if the current is too small, the mixture will heat up slowly and fail to reach the required temperature. Therefore, how to accurately control the production parameters such as temperature, internal pressure, screw speed, feeding speed, current size, etc. has become a problem to be solved by white plastic masterbatch manufacturers.

[0003] The Chinese invention patent with the publication number CN114805979A and the name of a process for preparing a masterbatch discloses a process for preparing a masterbatch, which is obtained by weighing raw materials, color powder, dispersant, processing aid and filler in proportion and sand grinding, and the obtained is used as a pre-treated pigment. The carrier is put into a mixing and blending machine for mixing, the mixing speed is 400 rpm, the mixing temperature is controlled at 70°C, and the time is 2 minutes. The pre-treated pigment is added to the mixing and blending machine at a mixing speed of 600 rpm, the mixing temperature is controlled at 70°C, and the time is 8 minutes to obtain a mixture. S2, the mixture is put into the hopper of a twin-screw extruder, the temperature in the extruder is controlled at 180-220°C, the screw speed is 500r / min, the head temperature is 220°C, and the screw speed is 350 rpm. S3. The mixture is melted by heat, and under the push of the screw of the twin-screw extruder, it undergoes physical and chemical reactions and flows out through the hole-shaped die. After the extrudate is cooled by water, it is cut into cylindrical pellets of 3×3mm in size by a pelletizer. S4. The pellets are dried at 80°C in a hot air circulation dryer for 3 hours to obtain masterbatches. This achieves the effect of making the pigment more dispersed in the carrier resin, so that the color stability of the product is higher and the color difference is smaller, overcoming the problems of color instability and large color difference when the existing ABS masterbatch is colored. However, this technical solution cannot control the temperature and internal pressure in the screw extruder, and the filtering effect cannot be guaranteed. Summary of the invention

[0004] The purpose of the present invention is to provide an ABS white plastic production method and system in view of the deficiencies in the prior art, so as to solve the problem that in the existing white plastic production process, the production parameters such as temperature, internal pressure, screw speed, feeding speed, current size, etc. cannot be accurately controlled, thereby resulting in the finished product color being yellowish or bluish and failing to achieve the desired finished product color.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] A method for producing ABS white plastic masterbatch, comprising the following steps:

[0007] (1) ABS raw materials, color powder, dispersant and processing aids are placed in a mixer through a feeding device according to a required proportion and mixed and stirred to obtain a mixture;

[0008] (2) feeding the mixed material obtained by fully mixing and stirring in step (1) into a twin-screw pelletizer for mixing, extruding and drawing, wherein the process conditions of the twin-screw pelletizer are as follows: the temperature control of the main engine of the twin-screw pelletizer is divided into ten sections, and the corresponding temperature is set for each section, the head temperature is 210° C., the melt temperature is 200° C., the screen changing temperature is 200° C., the main engine current is 45A-170A, the screw speed is 450RPM-1200RPM, and the feeding speed is 20RPM-1000RPM;

[0009] (3) A filtering mechanism is provided at the discharge port of the twin-screw pelletizer in step (2), the filtering structure comprising a porous plate with a plurality of raw material through holes at the end surface, and a filter mesh group provided inside the porous plate, the filter mesh group comprising three layers of filter meshes, wherein the filter mesh located in the middle layer is a high-mesh filter mesh, and the filter meshes located on both sides are low-mesh filter meshes;

[0010] (4) The mixed material after being drawn in step (2) is cooled and dried through a cooling water tank and air drying equipment, and then pelletized and bagged to obtain an ABS white plastic masterbatch finished product or an ABS white plastic semi-finished product.

[0011] The ten temperature sections of the main machine in step (2) are: first section: 180°C, second section: 190°C, third section: 200°C-210°C, fourth section: 200°C-210°C, fifth section: 180°C-200°C, sixth section: 180°C, seventh section: 180°C, eighth section: 180°C, ninth section: 180°C-210°C, tenth section: 180°C-210°C.

[0012] The filter screen group in step (3) includes a first layer of filter screen, a second layer of filter screen and a third layer of filter screen, wherein the mesh numbers of the first layer of filter screen and the third layer of filter screen are 18 to 30 meshes, and the mesh number of the second layer of filter screen is 60 to 100 meshes.

[0013] By using filters with different mesh sizes, the internal pressure of the extruder can be controlled. The higher the mesh size, the greater the internal pressure. The internal pressure of the extruder will affect the residence time of the mixed material in the extruder and the temperature inside the extruder. Therefore, using filters with different mesh sizes will affect the color of the white masterbatch.

[0014] In the production of white plastics, due to the particularity of white, the number and size of black spots in the finished product often become one of the important criteria for whether the finished product is qualified. Therefore, in the production process of white plastic masterbatch, a high-mesh filter is used to reduce the impact of black spots. In the current use of the filter screen for the screw extruder, only the filtering function of the filter screen is considered. In actual use, the higher the mesh number of the filter screen, the greater the resistance to the extrusion of the screw extruder. Therefore, by adjusting the screw speed and the screw extruder temperature, the mesh number of the second layer of the filter screen is adjusted, or by selecting the mesh number of the second layer of the filter screen, the screw speed and the screw extruder temperature are matched, so as to adjust the internal temperature of the screw extruder, and avoid the problem of yellow or blue color of the finished product due to the high or low internal pressure of the screw extruder.

[0015] The present invention provides a three-layer filter screen to protect the high-mesh filter screen. The main principle is that when the screw of the screw extruder rotates, the fluid mixture will generate a rotating torque and an outward extrusion force. The higher the mesh number of the filter screen, the thinner it is and the more expensive it is. Therefore, when only one high-mesh filter screen is used, it is easy to deform under the action of the torque and the outward extrusion force, thereby reducing or losing the filtering effect. At this time, the filter screen needs to be replaced, which makes the service life of the filter screen low and increases the production cost. There are also manufacturers that use double-piece high-mesh filter screens, but they can only relatively effectively solve the effect from the extrusion force and enhance the performance of anti-extrusion force. However, they cannot produce a good defensive effect on the torque, which also reduces the service life of the filter screen, and the use of double high-number filter screens also greatly increases the production cost. Therefore, the present invention adopts a three-layer mesh combination mode in which the filter screen located in the middle layer is a high-mesh filter screen and the filter screens located on both sides are low-mesh filter screens, so that the low-mesh filter screen corresponding to the screw rod plays a preliminary filtering role while reducing the deformation effect of the torsion force on the high-mesh filter screen, the high-mesh filter screen in the middle layer is used to filter finer impurities, and the third low-mesh filter screen located at the outlet end plays a supporting role for the high-mesh filter screen in the middle layer, thereby reducing the deformation effect of the extrusion force on the high-mesh filter screen. The temperature, pressure and mixing degree in the pelletizing machine can be controlled by the number of filter screens and the size of the filter screen mesh.

[0016] The feeding equipment comprises a vacuum negative pressure material suction device and a weighing barrel.

[0017] The step (1) further comprises: placing the ABS raw material, the ABS white plastic semi-finished product, the color powder, the dispersant and the processing aid in a desired proportion through a feeding device into a mixer for thorough mixing and stirring to obtain a mixture.

[0018] In the prior art, since the plastic raw material is in granular form, when mixing with the toner, the toner is coated on the ABS raw material through a processing aid. During the mixing process, the toner not coated on the ABS raw material is easy to sink to the bottom of the stirring device, forming a stratified phenomenon with the ABS raw material on the top and the toner on the bottom, so that the ABS raw material and the toner cannot be fully mixed, thereby affecting the color of the white plastic masterbatch.

[0019] The present invention prepares semi-finished products accounting for 50% to 80% of the finished product formula ratio in advance, and then mixes the semi-finished products with raw materials of the remaining formula ratio, so that when preparing the finished product, the amount of color powder added will be greatly reduced, so that the color powder can be mixed with the ABS raw material more evenly, thereby effectively solving the problem of color powder sinking to the bottom when the raw materials are mixed in the prior art, and thus the powder can be well removed.

[0020] The toner is an organic pigment and / or an inorganic pigment, wherein the organic pigment includes toners of various colors; the inorganic pigment includes titanium dioxide and carbon black.

[0021] A system for producing ABS white plastic masterbatch for implementing the method.

[0022] The beneficial effects of the present invention are as follows: the ABS white plastic production method of the present invention divides the temperature of the screw extruder into ten sections, performs segmented precise temperature control, and defines the head temperature, melt temperature and screen change temperature at the same time, so that the temperature in the ABS white plastic production process can be well controlled and limited, and the main machine current is limited to 45A-170A, the screw speed is 450RPM-1200RPM, the feeding speed is 20RPM-1000RPM and other parameters, so as to reduce the influence of the main machine current, the screw speed and the feeding speed on the color of the finished product, and each parameter can be adjusted to stabilize the color and fine-tune the color, so that there is no need to modify the formula ratio, thereby improving production efficiency. By arranging a filtering mechanism at the outlet of the screw extruder, and arranging three layers of filter screens in the filtering mechanism, wherein the filter screen located in the middle layer is a high mesh filter screen, and the filter screens located on both sides are low mesh filter screens, so that while achieving efficient filtration of impurities, the internal pressure of the screw extruder can be controlled, and the high mesh filter screen can be well protected, and the service life of the filter screen can be improved. DETAILED DESCRIPTION

[0023] Embodiment 1: This embodiment provides a method for producing ABS white plastic masterbatch, which comprises the following steps:

[0024] (1) ABS raw materials, color powder, dispersant and processing aids are placed in a mixer through a feeding device according to a required proportion and mixed and stirred to obtain a mixture;

[0025] (2) feeding the mixed material obtained by fully mixing and stirring in step (1) into a twin-screw pelletizer for mixing, extruding and drawing, wherein the process conditions of the twin-screw pelletizer are as follows: the temperature control of the main engine of the twin-screw pelletizer is divided into ten sections, and the corresponding temperature is set for each section, the head temperature is 210° C., the melt temperature is 200° C., the screen changing temperature is 200° C., the main engine current is 45A-170A, the screw speed is 450RPM-1200RPM, and the feeding speed is 20RPM-1000RPM;

[0026] (3) A filtering mechanism is provided at the discharge port of the twin-screw pelletizer in step (2), the filtering structure comprising a porous plate with a plurality of raw material through holes at the end surface, and a filter mesh group provided inside the porous plate, the filter mesh group comprising three layers of filter meshes, wherein the filter mesh located in the middle layer is a high-mesh filter mesh, and the filter meshes located on both sides are low-mesh filter meshes;

[0027] (4) The mixed material after being drawn in step (2) is cooled and dried through a cooling water tank and air drying equipment, and then pelletized and bagged to obtain an ABS white plastic masterbatch finished product or an ABS white plastic semi-finished product.

[0028] The ten temperature sections of the main machine in step (2) are: first section: 180°C, second section: 190°C, third section: 200°C-210°C, fourth section: 200°C-210°C, fifth section: 180°C-200°C, sixth section: 180°C, seventh section: 180°C, eighth section: 180°C, ninth section: 180°C-210°C, tenth section: 180°C-210°C.

[0029] The filter screen group in step (3) includes a first layer of filter screen, a second layer of filter screen and a third layer of filter screen, wherein the mesh numbers of the first layer of filter screen and the third layer of filter screen are 18 to 30 meshes, and the mesh number of the second layer of filter screen is 60 to 100 meshes.

[0030] The feeding equipment comprises a vacuum negative pressure material suction device and a weighing barrel.

[0031] The toner is an organic pigment and / or an inorganic pigment, wherein the organic pigment includes toners of various colors; the inorganic pigment includes titanium dioxide and carbon black.

[0032] A system for producing ABS white plastic masterbatch for implementing the method.

[0033] Embodiment 2: This embodiment provides a method for producing ABS white plastic masterbatch, and its steps are basically the same as those of Embodiment 1, except that:

[0034] (1) ABS raw materials, ABS white plastic semi-finished products, color powder, dispersant and processing aids are placed in a mixer through a feeding device according to a required proportion and fully mixed and stirred to obtain a mixture.

[0035] (2) feeding the mixed material obtained by fully mixing and stirring in step (1) into a twin-screw pelletizer for mixing, extruding and drawing, wherein the process conditions of the twin-screw pelletizer are as follows: the temperature control of the main engine of the twin-screw pelletizer is divided into ten sections, and the corresponding temperature is set for each section, the head temperature is 210° C., the melt temperature is 200° C., the screen changing temperature is 200° C., the main engine current is 45A-170A, the screw speed is 450RPM-1200RPM, and the feeding speed is 20RPM-1000RPM;

[0036] (3) A filtering mechanism is provided at the discharge port of the twin-screw pelletizer in step (2), the filtering structure comprising a porous plate with a plurality of raw material through holes at the end surface, and a filter mesh group provided inside the porous plate, the filter mesh group comprising three layers of filter meshes, wherein the filter mesh located in the middle layer is a high-mesh filter mesh, and the filter meshes located on both sides are low-mesh filter meshes;

[0037] (4) The mixed material after being drawn in step (2) is cooled and dried through a cooling water tank and air drying equipment, and then pelletized and bagged to obtain a finished ABS white plastic masterbatch.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the patent scope of the present invention. Therefore, all changes in the method steps made using the contents of the present invention specification are included in the protection scope of the present invention.

Claims

1. A method for producing ABS white plastic masterbatch, characterized in that: It includes the following steps: (1) ABS raw materials, color powder, dispersant and processing aids are placed in a mixer through a feeding device according to a required proportion and mixed and stirred to obtain a mixture; (2) feeding the mixed material obtained by fully mixing and stirring in step (1) into a twin-screw pelletizer for mixing, extruding and drawing, wherein the process conditions of the twin-screw pelletizer are as follows: the temperature control of the main engine of the twin-screw pelletizer is divided into ten sections, and the corresponding temperature is set for each section, the head temperature is 210° C., the melt temperature is 200° C., the screen changing temperature is 200° C., the main engine current is 45A-170A, the screw speed is 450RPM-1200RPM, and the feeding speed is 20RPM-1000RPM; (3) A filtering mechanism is provided at the discharge port of the twin-screw pelletizer in step (2), the filtering structure comprising a porous plate with a plurality of raw material through holes at the end surface, and a filter mesh group provided inside the porous plate, the filter mesh group comprising three layers of filter meshes, wherein the filter mesh located in the middle layer is a high-mesh filter mesh, and the filter meshes located on both sides are low-mesh filter meshes; (4) The mixed material after being drawn in step (2) is cooled and dried through a cooling water tank and air drying equipment, and then pelletized and bagged to obtain an ABS white plastic masterbatch finished product or an ABS white plastic semi-finished product.

2. The method for producing ABS white plastic masterbatch according to claim 1, characterized in that: The ten temperature sections of the main machine in step (2) are: first section: 180°C, second section: 190°C, third section: 200°C-210°C, fourth section: 200°C-210°C, fifth section: 180°C-200°C, sixth section: 180°C, seventh section: 180°C, eighth section: 180°C, ninth section: 180°C-210°C, tenth section: 180°C-210°C.

3. The method for producing ABS white plastic masterbatch according to claim 1, characterized in that: The filter screen group in step (3) includes a first layer of filter screen, a second layer of filter screen and a third layer of filter screen, wherein the mesh numbers of the first layer of filter screen and the third layer of filter screen are 18 to 30 meshes, and the mesh number of the second layer of filter screen is 60 to 100 meshes.

4. The method for producing ABS white plastic masterbatch according to claim 1, characterized in that: The feeding equipment comprises a vacuum negative pressure material suction device and a weighing barrel.

5. The method for producing ABS white plastic masterbatch according to claim 1, characterized in that: The step (1) further comprises: placing the ABS raw material, the ABS white plastic semi-finished product, the color powder, the dispersant and the processing aid in a desired proportion through a feeding device into a mixer for thorough mixing and stirring to obtain a mixture.

6. The method for producing ABS white plastic masterbatch according to claim 1, characterized in that: The toner is an organic pigment and / or an inorganic pigment, wherein the organic pigment includes toners of various colors; the inorganic pigment includes titanium dioxide and carbon black.

7. An ABS white plastic masterbatch production system for implementing the method according to any one of claims 1 to 6.