KR102172420B1 - Production process of pellet extrusion capable of controlling crystallinity and a pellet produced therefrom - Google Patents

Abstract

The present invention relates to an extrusion manufacturing process of a pellet, which is a resin mixture for melt processing, and a pellet produced therein, and more particularly, to an extrusion manufacturing process characterized in that it is possible to control the degree of crystallinity. Preparing raw materials for pellet production (S10); Mixing step (S20) of mixing the prepared raw materials; Injecting the resin mixed in the mixing step into an extruder and melt-mixing the extrusion step (S30); A cooling step (S40) capable of controlling the crystallinity of the extruded resin by controlling the length and speed of the strand using at least one roller while transferring the extruded strand of the resin; And there is provided a pellet extrusion manufacturing process capable of controlling the crystallinity including a pellet extrusion manufacturing process capable of controlling the crystallinity including the step of discharging the resin into pellets after the cooling step and selecting according to size (S50). Therefore, it provides an effect of controlling the degree of crystallinity by easily adjusting the length, time, and speed of the strand.

Description

[Production process of pellet extrusion capable of controlling crystallinity and a pellet produced therefrom}

The present invention relates to a pellet extrusion manufacturing process capable of controlling the crystallinity and to the pellets produced therein, and more particularly, when manufacturing pellets of various plastic resins, extruded by controlling the length and speed of the strands in the cooling step of the extrusion process. It relates to a pellet extrusion manufacturing process capable of controlling the crystallinity of resin.

Plastic resins are easy to process and have excellent properties such as tensile strength, elastic modulus, heat resistance, and impact resistance, so they are used for various purposes such as automobile parts, helmets, electric equipment parts, spinning machine parts, toys, or pipes. Therefore, various plastic polymer resins are compounded and provided by injection and molding using an extruder.

In general, an extruder for manufacturing pellets using a plastic polymer resin includes a hopper that feeds raw materials, an extrusion head that melts the raw materials introduced through the hopper, mixes and extrudes the melt through a screw, and molds it into a strand shape, etc. It is manufactured by cooling the extrudate discharged through this. In addition, it comprises a cutter device for cutting the cooled extrudate to a certain size.

Meanwhile, in the manufacture of pellets using such a plastic polymer resin, it is important to rapidly solidify the outermost layer of the pellets by rapidly cooling in the above-described various process steps, especially in the cooling step after extrusion. Nevertheless, there is a problem in that the productivity efficiency for the installation area is deteriorated because the equipment in the cooling stage has to be installed from 10 m to 20 m.

In addition, raw materials for a wide range of plastic polymer resins may have properties that are not suitable for processing. For example, lack of sufficient cooling capacity for processing due to narrow melting point range, slow heat conduction and crystallization, low miscibility of liquids in the blending process, mixing and blending, etc. Can be lifted.

Therefore, in manufacturing a plastic polymer resin, research to improve physical properties such as miscibility and crystallinity in the processing process is ongoing.

Korean Patent Publication No. 10-1357647 provides an apparatus and method that enable fine control of the thermal shear properties and fluidity components of raw materials in a pellet manufacturing process. In detail, prior to the die plate, a melt cooler located upstream of the cooling extruder and, if necessary, a secondary melt cooler located downstream of the cooling extruder, are added to heat and shear a polymer raw material, composition, dispersion or solution with a narrow melting point range. , And by controlling the flow characteristics, it discloses to provide a pellet by controlling the physical properties of a raw material that is difficult to pelletize. However, although it is mentioned that it is possible to fine-tune the heat, shear and fluidity, there is a limitation in that there is no mention of crystallinity.

Korean Patent Publication No. 10-1357647 discloses a method and apparatus for manufacturing underwater pellets for crystallizing polymer pellets without involving a heating process and drying continuous crystalline polymers. More specifically, to provide a method and apparatus for pelletizing and continuously drying polyester, polyamide, polycarbonate, thermoplastic polyurethane, and each of their copolymers in water so that crystallization of pellets or granules is initiated by itself. And, accordingly, it provides that it is possible to produce pellets and granules showing the desired crystallinity. However, there is a limit to being limited to underwater pellet manufacturing in that it includes a process of cutting the extruded strand into pellets in water after the extruding process.

In the present invention, while solving the above problems, it is intended to provide a process in which raw materials of polymer resins are mixed and extruded to more efficiently control physical properties in the cooling step, and in particular, to propose a process for extruding pellets capable of controlling crystallinity.

Korean Registered Patent Publication No. 10-1357647 (2014.02.03.) Korean Registered Patent Publication No. 10-1379345 (2014.03.28)

The present invention has been devised to solve the above problems, and an object of the present invention is to provide a pellet extrusion manufacturing process capable of controlling the crystallinity.

In the manufacturing process of the pellets according to the present invention, it is an object of the present invention to provide a compound blended in an optimum ratio by uniformly mixing the pellet composition compound during mixing in the mixing step.

According to the present invention, it is an object of the present invention to control the crystallization rate by easily adjusting the crystallinity of the extruded resin by adjusting the length, time, and speed of the strand in the cooling step.

In addition, the pellets with controlled crystallinity produced through the extrusion manufacturing process are intended to improve molding processability during the injection process, and to improve physical properties such as mechanical properties and heat resistance.

According to the present invention for achieving this object, there is provided a pellet extrusion manufacturing process capable of controlling the crystallinity.

According to an embodiment of the present invention, the step of preparing raw materials for pellet production (S10); Mixing step (S20) of mixing the prepared raw materials; Injecting the resin mixed in the mixing step into an extruder and melt-mixing the extrusion step (S30); A cooling step (S40) capable of controlling the crystallinity of the extruded resin by controlling the length and speed of the strand using at least one roller while transferring the extruded strand of the resin; And a pellet extrusion manufacturing process capable of controlling crystallinity including the step of discharging the resin into pellets after the cooling step (S50) and selecting each size (S50).

In the step (S10) of preparing the raw material for manufacturing the pellet, the raw material includes 50 to 100 parts by weight of polypropylene, 0.05 to 1 part by weight of a heat stabilizer, 5 to 50 parts by weight of a filler, and 0.1 to 5 parts by weight of an additive.

In addition, the mixing step (S20) is at least one selected from a ribbon blender, a V-type blender, and a Henchel Mixer in a mixer, the mixing speed is 50 to 1000 rpm, the mixing time is 1 It is characterized in that it proceeds for minutes to 20 minutes.

The resin mixed in the mixing step is introduced into the extruder, melt-mixed, and in the extrusion step (S30), the mixed resin is directly introduced into the extruder, and the filler is directly introduced into the extruder without the mixing step.

In the step (S30) of putting the mixed resin into an extruder, melt mixing, and extruding, the inside of the extruder is 150 to 300°C, and the speed of the screw is 50 to 800 rpm.

According to an embodiment of the present invention, in the cooling step (S40), the crystallinity of the extruded resin can be adjusted by adjusting the length and speed of the strand using at least one roller while transferring the extruded resin strand. , The cooling is characterized in that it proceeds in a cooling water bath of 5 to 50 ℃.

In addition, the length of the strand is 5 to 15 m, the first roller is positioned under the strand, and includes at least one section including at least one section in which the transfer inclination angle of the strand is 25 to 60° and proceeds in the forward direction. . The strand includes a section in which the second roller is rolled backward in a moving forward direction and then proceeds in a moving forward direction again. In this case, it is characterized in that the length of the strand movement can be manually adjusted by connecting the belt chain to the roller in the section in which the strand moves backward in the moving forward direction, winds the second roller, and then proceeds in the moving forward direction again.

In addition, the moving speed of the strand is characterized in that 0.5 to 3m/sec.

After the cooling step, the pellets discharged in the step of discharging the resin into pellets and sorting by size (S50) are separated and sorted using a vibration vibrator and a mesh. In this case, the mesh of the net is provided to be 3 to 7mm, preferably 5mm.

According to an embodiment of the present invention, the pellets separated and sorted by passing through the mesh to a size smaller than the mesh of the mesh are transferred to a packer hopper and automatically packaged (S60); the crystallinity control further comprises: A possible pellet extrusion manufacturing process is provided.

According to an embodiment of the present invention, a pellet capable of adjusting the degree of crystallinity manufactured by the extrusion manufacturing process according to the above is provided, and in this case, at least one of a cylinder, a sphere, and an elliptical sphere is provided.

As described above, there is an effect of providing a pellet extrusion manufacturing process capable of controlling the crystallinity according to the present invention.

In the manufacturing process of the pellets according to the present invention, when mixing in the mixing step, there is an effect of uniformly mixing the pellet composition compound to provide a compound blended in an optimum ratio.

In addition, according to the present invention, there is provided a cooling step capable of controlling the crystallinity of the extruded resin by adjusting the length and speed of the strand using at least one roller while transporting the strand of the extruded resin, thereby controlling the crystallization rate. Provides an effect that can be done.

Therefore, the pellets produced through the extrusion manufacturing process improve molding processability during the injection process, and provide an effect of improving mechanical properties and heat resistance.

1 is a flow chart schematically showing a pellet extrusion process capable of adjusting crystallinity according to an embodiment of the present invention.
2 is a view showing a cooling step (S40) capable of adjusting crystallinity in a process sequence according to an embodiment of the present invention.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments are intended to complete the disclosure of the present invention, and those skilled in the art to which the present invention pertains. It is provided to fully inform the person of the scope of the invention, and the invention is only defined by the scope of the claims.

The shape, size, ratio, angle, number, etc. for describing the embodiments of the present invention are exemplary, and the present invention is not limited thereto. In addition, in describing the present invention, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

When'include','have','consists of' and the like mentioned in the present specification are used, other parts may be added unless'only' is used. In the case of expressing the constituent elements in the singular, it includes the case of including the plural unless specifically stated otherwise.

In interpreting the constituent elements, it is interpreted as including an error range even if there is no explicit description.

In addition, in the case of a description of the positional relationship, for example, if the positional relationship of the two parts is described as'upper,' upper,' lower, and As long as'direct' is not used, there may be one or more other parts between the two parts.

And, in the case of a description of a temporal relationship, for example, when a temporal predecessor relationship is described such as'after','following','after after','before', etc.,'right' or ' It may also include cases that are not continuous unless'direct' is used.

In addition, first, second, etc. are used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one component from another component. Accordingly, the first component mentioned below may be a second component within the technical idea of the present invention.

In addition, the'X-axis direction','Y-axis direction', and'Z-axis direction' should not be interpreted only as a geometrical relationship in which the relationship between each other is vertical, and within the range in which the configuration of the present invention can function functionally. It may mean having a wider direction.

In addition, the term'at least one' is to be understood as including all possible combinations from one or more related items. For example, the meaning of'at least one of the first item, the second item and the third item' is not only the first item, the second item, or the third item, but also the second item, the second item, and the third item. It may mean a combination of all items that can be presented from more than one.

Each of the features of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments can be implemented independently of each other or can be implemented together in a related relationship. May be.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view schematically showing a pellet extrusion process capable of adjusting crystallinity according to an embodiment of the present invention.

2 is a view showing a cooling step (S40) capable of adjusting crystallinity in a process sequence according to an embodiment of the present invention.

According to an embodiment of the present invention the drawings, the step of preparing raw materials for pellet production (S10); Mixing step (S20) of mixing the prepared raw materials; Injecting the resin mixed in the mixing step into an extruder and melt-mixing the extrusion step (S30); A cooling step (S40) capable of controlling the crystallinity of the extruded resin by controlling the length and speed of the strand using at least one roller while transferring the extruded strand of the resin; And a pellet extrusion manufacturing process capable of controlling crystallinity including the step of discharging the resin into pellets after the cooling step (S50) and selecting each size (S50).

In the step (S10) of preparing the raw material for manufacturing the pellet, the raw material is provided with 50 to 100 parts by weight of polypropylene, 0.05 to 1 part by weight of a heat stabilizer, 5 to 50 parts by weight of a filler, and 0.1 to 5 parts by weight of an additive.

The polypropylene is an olefin-based resin that is widely used as a general-purpose resin, and has a wide variety of uses, such as being used as a material such as fiber, rope, film, various household goods, and industrial materials. The reason why polypropylene resin is used for various purposes is that it has no toxicity, has excellent physical properties, and has good processability compared to other plastics. In addition, the specific gravity of 0.9 to 0.92 g / cm ³ has the advantage of being the lightest and most transparent plastics. Accordingly, 50 to 100 parts by weight of polypropylene is provided as a base resin for producing the pellets according to the present invention.

The heat stabilizer may be a phosphite based heat stabilizer, and as a phosphite based heat stabilizer, diphenyl isooctyl phosphite, distearyl pentaeryl diphosphite Etc. can be provided. 0.01 to 1 part by weight may be provided, and if it is less than 0.01, the thermal stability does not appear, and if it exceeds 1.0, the contribution to the improvement of the thermal stability is low, which is disadvantageous in terms of economy.

The fillers include inorganic fibers such as glass fibers and carbon fibers, those coated with metal on inorganic fibers, mica, glass beads, inorganic substances such as potassium titanate, magnesium carbonate, and carbon black, and metals such as iron, copper, zinc, and aluminum. Or alloys, and fibers and powders of these oxides. Preferably, glass fibers and carbon fibers may be provided. The filler is provided in an amount of 20 to 50 parts by weight, and when it is less than 20, its role as a filler is insufficient, and when it exceeds the above range, there is difficulty in improving strength and molding due to crushing due to collision between the fillers.

According to a preferred embodiment of the present invention, the raw material may further contain an additive. As an additive, the lubricant, antioxidant, ultraviolet stabilizer, and flame retardant may be provided. In other words, the polymer resin prepared by mixing the raw materials can be used as interior and exterior parts of automobiles and parts of electric and electronic products, and additives such as lubricants, antioxidants, ultraviolet stabilizers, and flame retardants that are commonly used are added. It can be used, but is not limited thereto.

According to a preferred embodiment of the present invention, the lubricant may be a polyethylene-based low molecular weight wax, a Montan wax, or the like, and a hindered phenol and a phosphite compound may be provided as the antioxidant. In addition, a hindered amine and a benzotriazole compound may be provided as the ultraviolet stabilizer, and as the flame retardant, RDP (Resorcinol Diphosphate) and TPP (Triphenyl phosphate), which are used as phosphorus-based flame retardants as well as bromine-based flame retardants, are commonly known. ), a phosphorus-based flame retardant such as BDP may be provided.

According to a preferred embodiment of the present invention, the mixing step (S20) comprises mixing in a mixer using at least one selected from a ribbon blender, a V-type blender, and a Henchel Mixer. to provide. In this case, the mixing speed is provided at 500 to 1,000 rpm, and the mixing time is characterized in that it proceeds for 1 minute to 20 minutes. Mixing proceeds at the above speed and time, and the raw materials of the polymer composition are appropriately premixed and distributed evenly in the entire resin, so that it can be provided with an extruder so that the overall distribution is uniform.

According to a preferred embodiment of the present invention, the resin mixed in the mixing step is introduced into an extruder, melt-mixed, and in the extrusion step (S30), the mixed resin is directly introduced into the extruder, and the filler is directly introduced into the extruder without the mixing step. Provide what you put in.

According to a preferred embodiment of the present invention, in the step (S30) of melt-mixing and extruding the mixed resin into an extruder, the inside of the extruder is 150 to 300°C, and the speed of the screw is 50 to 800 rpm. There is provided a pellet extrusion manufacturing process capable of controlling the degree of crystallinity. In addition, it is possible to proceed with the process by optimizing process conditions according to various raw materials introduced in the melting process. The extruder is not particularly limited, and a twin screw extruder is preferably provided.

According to an embodiment of the present invention, in the cooling step (S40), the crystallinity of the extruded resin can be adjusted by adjusting the length and speed of the strand using at least one roller while transferring the extruded resin strand. , The cooling is provided to proceed in a cooling water bath of 5 to 50 ℃.

In addition, the length of the strand is 5 to 15 m, the first roller is positioned under the strand, and includes at least one section including at least one section in which the transfer inclination angle of the strand is 25 to 60° and proceeds in the forward direction. . Compared to cooling the strand by going straight without a feed inclination angle, proceeding including the inclination angle may extend the time of the cooling step by the cooling water tank and increase the area. Accordingly, it provides an effect of improving the degree of crystallinity. When the conveying inclination angle is less than 25 or exceeds 60, a bar that contributes to the improvement of crystallinity is insufficient, and thus a range of 25 to 60 is provided.

According to a preferred embodiment of the present invention, the strand includes a section that moves backward in a moving forward direction, winds the second roller, and then proceeds in a moving forward direction again. Accordingly, it is possible to provide a pellet extrusion process capable of controlling the crystallization rate by increasing the moving area of the strand and increasing the cooling time than the conventional technology. A section in which the strand moves backward in the moving direction, winds the second roller, and then proceeds in the moving forward direction may be adjusted. Accordingly, the total length of the strand is 5 to 50 m is provided. Therefore, it is possible to provide an effect of controlling the degree of crystallinity by adjusting the moving length of the strand in the cooling step, increasing or decreasing the crystallization rate depending on the resin.

According to a preferred embodiment of the present invention, in this case, the length of the strand is manually adjusted by connecting the belt chain to the roller in the section in which the strand moves backward in the moving forward direction, winds the second roller, and then proceeds in the moving forward direction again. It is characterized by this possible. Referring to Figure 2, in the present invention, the moving length and area of the strand can be manually arbitrarily adjusted as necessary using a chain belt connected to a roller. Therefore, convenience of the process is provided by adjusting the length of the strand as necessary.

On the other hand, control of the crystallinity by adjusting the strands in this cooling step may vary depending on the resin to be produced. That is, in the case of a resin composition that derives the desired physical properties by improving the crystallinity, the transfer angle, transfer length, transfer speed, and transfer time of the strand can be adjusted to improve the crystallinity. It is possible, and it can be adjusted as needed in consideration of the kind and properties of the raw material of the resin.

According to a preferred embodiment of the present invention, after the cooling step, the pellets discharged in the step of discharging the resin into pellets and sorting by size (S50) are separated and sorted using a vibration vibrator and a mesh. In this case, it is provided that the mesh of the net is 3 to 7mm, preferably 5mm.

The step (S50) of discharging the resin into pellets after the cooling step and sorting by size (S50) is to provide a pellet molded article having a constant particle size depending on whether the first molded pellet is manufactured in a standardized size, and When pellets formed into a tank equipped with a vibrating vibrator are supplied, the pellets conforming to the standard through a through hole formed in the screen net are transferred to the 　packer hopper and automatically packaged. On the other hand, pellets that do not meet the specifications and their residues are separated and discharged.

Accordingly, according to a preferred embodiment of the present invention, the mesh of the mesh, preferably 3 to 7 mm, more preferably 5 mm or less, can be separated and sorted through the mesh. The pellets are transferred to the packer hopper and automatically packaged (S60). Therefore, it is distributed and packed by a certain weight, and then shipped after packaging.

According to a preferred embodiment of the present invention, a series of processes from the step of preparing raw materials for pellet production (S10) to the step of discharging the resin into pellets and sorting by size (S50) after the cooling step are continuously performed. As it is carried out, the pellets produced thereby are molded in a process capable of controlling the crystallinity, especially in the cooling step.

According to a preferred embodiment of the present invention, the shape of the pellets to be produced is not particularly limited, and for example, a cylinder, a sphere, an ellipse sphere, etc. are possible, but is not limited thereto. The size of the pellet may be manufactured according to the shape, for example, in the case of a spherical pellet, a diameter of 1 to 10 mm may be provided, and in the case of an elliptical spherical pellet, it may be provided in an oval shape with an aspect ratio of 0.1 to 1.0, and 1 to 10 mm length may be provided. In the case of cylindrical pellets, it may be provided within the range of 1 to 10 mm in diameter and 1 to 10 mm in length. However, it is not limited thereto.

Although the embodiments of the present invention have been described in more detail above, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, and the scope of the technical idea of the present invention is not limited by these embodiments.

Therefore, it should be understood that the embodiments described above are illustrative and non-limiting in all respects. The scope of protection of the present invention should be interpreted by the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Claims (15)

Preparing raw materials for pellet production (S10);
Mixing step (S20) of mixing the prepared raw materials;
Injecting the resin mixed in the mixing step into the extruder and melt-mixing the extrusion step (S30);
A cooling step (S40) capable of controlling the crystallinity of the extruded resin by adjusting the length and speed of the strand using at least one roller while transferring the extruded resin strand; And
In the pellet extrusion manufacturing process including the step of discharging the resin into pellets after the cooling step and sorting by size (S50);
In the cooling step (S40), the first roller is located under the strand, and the feed inclination angle of the strand is 25 to 60° and proceeds in a forward direction including at least one section, and the strand moves backward in the forward direction. A pellet extrusion manufacturing process capable of adjusting crystallinity, characterized in that it includes a section that proceeds in a moving forward direction after winding the second roller. The method of claim 1,
In the step (S10) of preparing the raw material for manufacturing the pellet, the raw material is polypropylene 50 to 100 parts by weight, a heat stabilizer 0.05 to 1 parts by weight, a filler 5 to 50 parts by weight, and an additive 0.1 to 5 parts by weight. Pellet extrusion manufacturing process possible. The method of claim 1,
The mixing step (S20) of mixing the prepared raw materials is at least one selected from a ribbon blender, a V-type blender, and a Henchel Mixer, and the mixing speed is 50 to 1000 rpm, and the mixing time A pellet extrusion manufacturing process capable of controlling crystallinity, characterized in that it proceeds for 1 to 20 minutes. The method of claim 1,
The resin mixed in the mixing step is introduced into the extruder, melt-mixed, and in the extrusion step (S30), the mixed resin is directly introduced into the extruder, and the filler is directly introduced into the extruder without the mixing step. Pellet extrusion manufacturing process. The method of claim 1,
The resin mixed in the mixing step is put into an extruder, melt-mixed, and the inside of the extruder is 150 to 300°C in the extrusion step (S30), and the speed of the screw is 50 to 800 rpm. fair. The method of claim 1,
In the cooling step (S40) in which the crystallinity of the extruded resin can be adjusted by adjusting the length and speed of the strand using at least one roller while transferring the extruded resin strand, cooling is performed by cooling water of 5 to 50°C. Pellet extrusion manufacturing process capable of controlling crystallinity, characterized in that it proceeds in a bath. delete delete The method of claim 1,
The strand moves backward in the moving forward direction, winds the second roller, and connects the belt chain to the roller in the section proceeding in the moving forward direction again, so that the length of the strand movement can be manually adjusted. Pellet extrusion manufacturing process. The method of claim 1,
In the cooling step (S40) in which the crystallinity of the extruded resin can be adjusted by adjusting the length and speed of the strand using at least one roller while transporting the strand of the extruded resin, the moving speed of the strand is 0.5 to 3 m Pellets extrusion manufacturing process capable of controlling crystallinity, characterized in that /sec. The method of claim 1,
After the cooling step, the pellets discharged in the step of discharging the resin into pellets and sorting by size (S50) are separated and sorted using a vibration vibrator and a mesh. The method of claim 11,
A pellet extrusion manufacturing process capable of adjusting crystallinity, characterized in that the mesh of the net is 3 to 7mm. The method of claim 11,
The pellets separated and sorted by passing through the mesh to a size less than the mesh of the mesh are transferred to a packer hopper and automatically packaged (S60); a pellet extrusion manufacturing process capable of adjusting crystallinity further comprising. Pellets capable of controlling the degree of crystallinity produced by the extrusion manufacturing process according to any one of claims 1 to 6 and 9 to 13. The pellets prepared according to claim 14 are pellets capable of controlling crystallinity, characterized in that at least one of a cylinder, a sphere, and an elliptical sphere.

Images