Method for adjusting 3d printing wire based on segment sequence structure

Abstract

The present application relates to 3D printing technology, aiming at providing a kind of method for preparing 3D printing wire based on chain segment sequence structure regulation.The method is that polylactic acid and polylactic acid copolymer with specific chain segment sequence structure are uniformly mixed, then granulated and stretched by melt extrusion, to obtain polylactic acid-based 3D printing wire;The polylactic acid copolymer with specific chain segment sequence structure refers to the polylactic acid-poly (caprolactone)-polylactic acid triblock copolymer or poly (lactic acid-co-caprolactone) random copolymer formed by ring-opening copolymerization of lactide and caprolactone.In the product of the present application, the polylactic acid copolymer with specific chain segment sequence structure can maintain the fusion between different components, while realizing the regulation of the strength and toughness of the printing wire, improving the toughness and interlayer adhesion of the wire, and significantly improving the printing efficiency.The preparation process of the present application is simple and easy to operate, and can realize large-scale industrial production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of 3D printing, in particular to a method for preparing 3D printing wire based on chain segment sequence structure regulation. BACKGROUND

[0002] 3D printing technology is a rapid prototyping technology developed in recent years, which uses digital model files as the basis, uses powder-like metal or plastic and other adhesion materials, and constructs objects through layer-by-layer printing. 3D printing technology can be applied in many fields, such as aerospace, medical, industrial design, automobile manufacturing, etc. Fused deposition modeling (FDM) technology is the most widely used 3D printing technology at present, which has high product performance, no pollution, simple and flexible operation, and is suitable for home, office use and design creation.

[0003] At present, more than 95% of the materials used in the field of degradable FDM materials are polylactic acid. Polylactic acid is a common biodegradable plastic with good degradability and biocompatibility, which can replace some general-purpose plastics for use in agriculture, packaging materials and clothing fields. However, polylactic acid used as 3D printing material still has many shortcomings, such as brittle, low interlayer bonding strength, and poor impact resistance. In order to improve the mechanical and heat resistance properties of polylactic acid and maintain the degradability of the material, some researchers have modified polylactic acid by adding natural fillers (such as natural fibers, chitosan, starch, etc.) through physical blending. For example, patent application CN105295106A reports a method for preparing 3D printing wire by using cellulose microfiber composite modified polylactic acid, which reduces the cost while improving the mechanical properties of the material; patent application CN108822511A also reports that cellulose nanocrystals are treated with alkali and coated with polyethylene oxide, which are used as modifiers to improve the mechanical properties and thermal stability of polylactic acid-based 3D printing wire. Although this method improves the mechanical properties of polylactic acid to some extent, it does not effectively improve the interlayer bonding strength of the printed device. This is because the FDM printing process is layer-by-layer extrusion and accumulation. After a period of cooling, the surface temperature of the lower layer plastic filament may have cooled to the glass transition temperature (T g ) or below, the chain segment movement has stopped, and the newly extruded plastic filament of the upper layer needs to heat the lower layer surface temperature again to T g above to induce chain segment movement and entangle the upper and lower layer surface chain segments together to obtain a certain bonding strength after cooling. For ordinary wire containing fillers or fibers, the larger the filling rate, the smaller the area of contact between the extruded filaments, and the fibers also hinder the movement of polylactic acid chain segments, resulting in that the interlayer bonding strength of ordinary fiber modified PLA wire is much lower than that of pure resin without adding fillers or fibers.

[0004] In addition, the current reported polylactic acid-based 3D printing wire has a slow printing speed, generally not more than 50 mm / s, and a long printing time for large models, and a low printing efficiency. If the printing speed of the ordinary polylactic acid 3D printing wire is further increased to 250 mm / s, the wire is prone to breakage and filament during printing, and the precision of the printed device is greatly reduced.

[0005] Therefore, the design and development of a polylactic acid-based wire capable of super-fast 3D printing meet the needs of practical applications. SUMMARY

[0006] The technical problem to be solved by the present application is to overcome the shortcomings in the prior art and provide a method for preparing 3D printing wire based on chain segment sequence structure.

[0007] To solve the technical problem, the solution of the present application is:

[0008] A method for preparing 3D printing wire based on chain segment sequence structure is provided, which comprises the following steps: uniformly blending polylactic acid and polylactic acid copolymer with specific chain segment sequence structure, and then melt-extruding, granulating, and melt-extruding and drawing to obtain polylactic acid-based 3D printing wire. The polylactic acid copolymer with specific chain segment sequence structure is a polylactic acid-poly-caprolactone-polylactic acid triblock copolymer (PLA-b-PCL-b-PLA) or a poly(lactic acid-co-caprolactone) random copolymer (PLCL) obtained by ring-opening copolymerization of lactide and caprolactone. In the polylactic acid copolymer, the mass fraction of lactide units is 80-95%, and the mass fraction of caprolactone units is 5-20%. The mass ratio of polylactic acid to polylactic acid copolymer is 80-95:5-20.

[0009] As a preferred embodiment of the present application, in the poly(lactic acid-co-caprolactone) random copolymer (PLCL), the average chain segment length of lactide units (LLLL) is 5-20, and the average chain segment length of caprolactone units (CCCC) is 1-2.

[0010] As a preferred embodiment of the present application, the method specifically comprises the following steps:

[0011] (1) The polylactic acid and the polylactic acid copolymer are weighed according to the mass fraction, mixed uniformly after drying treatment, and the mixed raw material is obtained;

[0012] (2) The mixed raw material is added to a double-screw extruder, melt-plasticized, and extruded and granulated to obtain a wire masterbatch;

[0013] (3) The wire masterbatch is added to a single-screw extruder, melt-plasticized, drawn and shaped, and wound into a wire to obtain a 3D printing wire with a wire diameter of 1.75 mm±0.05 mm.

[0014] As a preferred scheme of the present application, the working temperature of the twin-screw extruder and the single-screw extruder is 180-230 DEG C.

[0015] As a preferred scheme of the present application, in the blending raw material or the wire masterbatch, further incorporate any one or more of the following auxiliary materials or agents: chain extender, nucleating agent, plasticizer, antioxidant, anti-hydrolysis agent and pigment.

[0016] Invention principle description:

[0017] When using ordinary polylactic acid-based 3D printing wire, the printing speed is generally not more than 50 mm / s, which is not suitable for super-fast printing (printing speed is more than 250 mm / s), the reasons are as follows: (1) because the FDM printing process is layer by layer extrusion accumulation, the increase of printing speed makes the solidification time of the accumulated layers shorten, so the model corner is easy to be silk, which leads to the rough surface of the model, not beautiful; (2) because 3D printing needs to use extrusion wheel to clamp the wire and send it into the heating port mold for melting, increasing the printing rate will increase the consumption of wire per unit time, which will increase the conveying speed of the extrusion wheel, so that the wire is easy to be brittle when it is pulled by the extrusion wheel, which increases the probability of wire breakage.

[0018] Compared with the natural fillers (such as natural fibers, chitosan, starch, etc.) or modifiers (such as cellulose nanocrystals treated with alkali and polyethylene oxide coated) in the prior art, the applicant changes the research and development idea and proposes a new solution, which uses a modified component with homology to the main raw material component polylactic acid of the printing wire to maintain the fusion between different components, and at the same time realizes the regulation of the strength and toughness of the printing wire.

[0019] The high molecular weight polylactic acid copolymer used as a modified component has a specific segment sequence structure, which can significantly affect the T g and mechanical properties of the material. The specific description is as follows:

[0020] In the polylactic acid triblock copolymer PLA-b-PCL-b-PLA, the whole polycaprolactone is embedded in the polylactic acid segment, and because the polycaprolactone itself has a lower melting point and T g , it acts as a flexible segment, so that the movement ability of the polylactic acid segment at both ends of the polycaprolactone is enhanced, which improves the toughness of the material, at the same time, the T g of the block copolymer is reduced, the solidification time is prolonged, and the interlayer bonding force is improved. Similarly, the length of the polycaprolactone sequence or the mass fraction of the copolymer unit caprolactone in the block copolymer has a significant influence on the printing effect. When the mass fraction of the caprolactone unit is 5%-20%, the prepared super-fast 3D printing wire has good interlayer bonding force and toughness.

[0021] In the poly(lactic acid-co-caprolactone) random copolymer (PLCL), due to the addition of the comonomer caprolactone, the T g and the melting point of the copolymer are reduced, so that the curing time can be prolonged and the material toughness is increased. When the average segment length of the lactide unit (LLLL) is short (<5), it is easy to cause the curing time to be too long and the mechanical properties to be poor, so that the printing accuracy is reduced. Therefore, the average segment length of the lactide unit (LLLL) in the random copolymer PLCL is set to 5-20, and the ultra-fast 3D printing wire prepared by blending the polylactic acid copolymer PLCL has good interlayer bonding force and toughness.

[0022] The application prepares the polylactic acid-based wire that can be ultra-fast 3D printed by segment sequence structure regulation, so that the wire winding, the conveying of the extrusion wheel and the interlayer bonding force are improved. More importantly, the obtained product can be perfectly applied to the ultra-fast 3D printing process, the printing speed can reach 250 mm / s, and the product printed has high strength and toughness.

[0023] Compared with the prior art, the application has the beneficial effects that:

[0024] 1. The application innovatively proposes a preparation method of the 3D printing wire, and the obtained product contains the polylactic acid copolymer with a specific segment sequence structure, can maintain the fusion between different components, and realizes the regulation of the strength and toughness of the printing wire, thereby improving the toughness and interlayer bonding force of the wire.

[0025] 2. The 3D printing wire prepared by the application has a printing speed of 250 mm / s during use, which significantly improves the printing efficiency and effectively expands the application field of 3D printing.

[0026] 3. The preparation process of the application is simple and easy to operate, and can realize large-scale industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The nuclear magnetic resonance carbon spectrum of the polylactic acid copolymer PLCL and the characteristic peak position of the typical sequence structure thereof are shown in the following table:

[0028] Figure 2 The standard spline for testing the interlayer bonding force is shown in the following table: DETAILED DESCRIPTION

[0029] The application will be further described in detail in combination with the drawings and specific embodiments, but the scope of protection of the application is not limited to the scope expressed by the embodiments.

[0030] First, the raw materials used in the examples or comparative examples of the application are described.

[0031] The polylactic acid copolymer with the specific segment sequence structure according to the present application refers to a polylactic acid-poly-caprolactone-polylactic acid triblock copolymer (PLA-b-PCL-b-PLA) or a poly(lactic acid-co-caprolactone) random copolymer (PLCL) prepared by ring-opening copolymerization of lactide and caprolactone. In each embodiment, the polylactic acid copolymer used is prepared by using L-lactide and ε-caprolactone through a known method, and the molecular weight is about 100,000. The present application does not have special restrictions on the specific preparation conditions. The L-lactide used is purchased from Henan Jindan Lactic Acid Technology Co., Ltd., with a purity of > 99%; the ε-caprolactone and cellulose are purchased from Aldrin Company; and the polylactic acid (brand R190) is purchased from Haizheng Biomaterials Co., Ltd.

[0032] In the printing process of the wire, any one or more of the following auxiliary materials or additives can be added according to the conventional process: chain extender (such as Joncryl ADR4300, Joncryl ADR4368 or Joncryl ADR4370, etc.), nucleating agent (such as benzene metal phosphate, diphenyl metal phosphate or benzene metal hypophosphite, etc.), plasticizer (such as acetyl tributyl citrate, tributyl citrate or tributyl phthalate, etc.), antioxidant (such as antioxidant 1010 or antioxidant 1076, etc.), anti-hydrolysis agent (such as carbodiimide, etc.) and pigment (such as organic pigment or inorganic pigment, etc.). The auxiliary materials or additives can be prepared by known methods or directly purchased.

[0033] Example 1

[0034] After 10 parts by mass of the random copolymer PLCL and 90 parts by mass of polylactic acid are dried and uniformly mixed, they are added to a double-screw extruder to be extruded at 190°C to prepare a wire masterbatch. Then, the wire masterbatch is added to a single-screw extruder to be extruded at 190°C. After melting, plasticizing, drawing, setting and winding, a wire with a diameter of 1.75 mm is obtained.

[0035] In the random copolymer PLCL, the mass fraction of lactide units is 95%, the mass fraction of caprolactone units is 5%, the average segment length of lactide units (LLLL) in the copolymer chain is 20, and the average segment length of caprolactone units is 2.

[0036] Example 2

[0037] After 10 parts by mass of the random copolymer PLCL and 90 parts by mass of polylactic acid are dried and uniformly mixed, they are added to a double-screw extruder to be extruded at 190°C to prepare a wire masterbatch. Then, the wire masterbatch is added to a single-screw extruder to be extruded at 190°C. After melting, plasticizing, drawing, setting and winding, a wire with a diameter of 1.75 mm is obtained.

[0038] The random copolymer PLCL has a mass fraction of 90% of lactide units and 10% of caprolactone units, and the average segment length of the lactide units (LLLL) in the copolymer chain is 13 and the average segment length of the caprolactone units is 1.

[0039] Example 3

[0040] The 10 parts by mass of the random copolymer PLCL and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment, and then were added into a double-screw extruder to be extruded at 190°C to prepare a thread masterbatch. Then the thread masterbatch was added into a single-screw extruder to be extruded at 190°C. After melting plasticization, drawing setting and winding, a thread with a diameter of 1.75 mm was obtained.

[0041] The random copolymer PLCL has a mass fraction of 85% of lactide units and 15% of caprolactone units, and the average segment length of the lactide units (LLLL) in the copolymer chain is 9 and the average segment length of the caprolactone units is 1.5.

[0042] Example 4

[0043] The 10 parts by mass of the random copolymer PLCL and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment, and then were added into a double-screw extruder to be extruded at 190°C to prepare a thread masterbatch. Then the thread masterbatch was added into a single-screw extruder to be extruded at 190°C. After melting plasticization, drawing setting and winding, a thread with a diameter of 1.75 mm was obtained.

[0044] The random copolymer PLCL has a mass fraction of 80% of lactide units and 20% of caprolactone units, and the average segment length of the lactide units (LLLL) in the copolymer chain is 5 and the average segment length of the caprolactone units is 1.3.

[0045] Example 5

[0046] The 5 parts by mass of the random copolymer PLCL and 95 parts by mass of polylactic acid were mixed uniformly after drying treatment, and then were added into a double-screw extruder to be extruded at 180°C to prepare a thread masterbatch. Then the thread masterbatch was added into a single-screw extruder to be extruded at 230°C. After melting plasticization, drawing setting and winding, a thread with a diameter of 1.75 mm was obtained.

[0047] The random copolymer PLCL has a mass fraction of 85% of lactide units and 15% of caprolactone units, and the average segment length of the lactide units (LLLL) in the copolymer chain is 9 and the average segment length of the caprolactone units is 1.5.

[0048] Example 6

[0049] 20 parts by mass of the random copolymer PLCL and 80 parts by mass of polylactic acid were mixed uniformly after drying treatment; and then were added into a twin-screw extruder to be extruded at 230°C to prepare a wire material masterbatch. Then the wire material masterbatch was added into a single-screw extruder to be extruded at 180°C; and then was subjected to melt plasticizing, drawing setting and winding to obtain a wire material with a wire diameter of 1.75 mm.

[0050] In the random copolymer PLCL, the mass fraction of lactide units is 85%, the mass fraction of caprolactone units is 15%, the average segment length of lactide units (LLLL) in the copolymer chain is 9, and the average segment length of caprolactone units is 1.5.

[0051] Example 7

[0052] 10 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment; and then were added into a twin-screw extruder to be extruded at 190°C to prepare a wire material masterbatch. Then the wire material masterbatch was added into a single-screw extruder to be extruded at 190°C; and then was subjected to melt plasticizing, drawing setting and winding to obtain a wire material with a wire diameter of 1.75 mm.

[0053] In the triblock copolymer PLA-b-PCL-b-PLA, the mass fraction of lactide units is 95%, and the mass fraction of caprolactone units is 5%.

[0054] Example 8

[0055] 10 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment; and then were added into a twin-screw extruder to be extruded at 190°C to prepare a wire material masterbatch. Then the wire material masterbatch was added into a single-screw extruder to be extruded at 190°C; and then was subjected to melt plasticizing, drawing setting and winding to obtain a wire material with a wire diameter of 1.75 mm.

[0056] In the triblock copolymer PLA-b-PCL-b-PLA, the mass fraction of lactide units is 90%, and the mass fraction of caprolactone units is 10%.

[0057] Example 9

[0058] 10 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment; and then were added into a twin-screw extruder to be extruded at 190°C to prepare a wire material masterbatch. Then the wire material masterbatch was added into a single-screw extruder to be extruded at 190°C; and then was subjected to melt plasticizing, drawing setting and winding to obtain a wire material with a wire diameter of 1.75 mm.

[0059] The mass fraction of the lactide unit in the triblock copolymer PLA-b-PCL-b-PLA is 85%, and the mass fraction of the caprolactone unit is 15%.

[0060] Example 10

[0061] After 10 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 90 parts by mass of polylactic acid are dried and uniformly mixed, they are added to a double-screw extruder and extruded at 190°C to prepare a wire material masterbatch. Then the wire material masterbatch is added to a single-screw extruder and extruded at 190°C. After melting, drawing, setting, and winding, a wire material with a wire diameter of 1.75 mm is obtained.

[0062] The mass fraction of the lactide unit in the triblock copolymer PLA-b-PCL-b-PLA is 80%, and the mass fraction of the caprolactone unit is 20%.

[0063] Example 11

[0064] After 5 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 95 parts by mass of polylactic acid are dried and uniformly mixed, they are added to a double-screw extruder and extruded at 180°C to prepare a wire material masterbatch. Then the wire material masterbatch is added to a single-screw extruder and extruded at 230°C. After melting, drawing, setting, and winding, a wire material with a wire diameter of 1.75 mm is obtained.

[0065] The mass fraction of the lactide unit in the triblock copolymer PLA-b-PCL-b-PLA is 85%, and the mass fraction of the caprolactone unit is 15%.

[0066] Example 12

[0067] After 20 parts by mass of the triblock copolymer PLA-b-PCL-b-PLA and 80 parts by mass of polylactic acid are dried and uniformly mixed, they are added to a double-screw extruder and extruded at 230°C to prepare a wire material masterbatch. Then the wire material masterbatch is added to a single-screw extruder and extruded at 180°C. After melting, drawing, setting, and winding, a wire material with a wire diameter of 1.75 mm is obtained.

[0068] The mass fraction of the lactide unit in the triblock copolymer PLA-b-PCL-b-PLA is 85%, and the mass fraction of the caprolactone unit is 15%.

[0069] Comparative Example 1

[0070] After 100 parts by mass of polylactic acid is dried and added to a double-screw extruder and extruded at 190°C to prepare a wire material masterbatch, the wire material masterbatch is added to a single-screw extruder and extruded at 190°C. After melting, drawing, setting, and winding, a wire material with a wire diameter of 1.75 mm for 3D printing is obtained.

[0071] Comparative Example 2

[0072] 10 parts by mass of cellulose and 90 parts by mass of polylactic acid were mixed uniformly after drying treatment, and then added into a twin-screw extruder to be extruded at 190°C to prepare a linear material masterbatch. Then the linear material masterbatch was added into a single-screw extruder to be extruded at 190°C. After melt plasticization, drawing, setting and linear material winding, a linear material for 3D printing with a linear diameter of 1.75 mm was obtained.

[0073] Performance test and analysis

[0074] Melting point and glass transition temperature test: differential scanning calorimeter (DSC) test was used, the test temperature was -50-200°C, and the temperature rising rate was 10°C / min.

[0075] Elongation at break: the elongation at break of the linear material was measured by SUNS universal material testing machine, the tensile speed was 10 mm / min, and the test temperature was 25±1°C. At least 5 parallel tests were used for each sample.

[0076] Interlayer bonding force test: the prepared linear material was loaded into a 3D printer (Shenzhen Chuangxi Sanwei, CR 5060pro), and a dumbbell-shaped sample (125 mm x 10 mm x 5 mm) was printed at a nozzle temperature of 250°C, a hot bed temperature of 60°C and a printing speed of 250 mm / s (as shown in Figure 2 Then the interlayer bonding force was measured by using SUNS universal material testing machine, that is, the maximum force in the tensile process of the sample was the interlayer bonding force, and the tensile speed was 10 mm / min. At least 5 parallel tests were used for each sample.

[0077] After testing, the data of the 3D printing linear materials prepared in Comparative Examples 1 and 2 and Examples 1-9 are shown in Table 1.

[0078] Table 1

[0079]

[0080] From the contents of each example and comparative example, and the above data, it can be seen that:

[0081] Compared with pure polylactic acid (Comparative Example 1), the traditional polylactic acid-based linear material added with cellulose (Comparative Example 2) cannot effectively improve the interlayer bonding force, while the polylactic acid-based linear material prepared by the method (Examples 1-12) has excellent toughness and interlayer bonding force. It is verified by actual use that the linear material prepared by the application can be used to prepare complex products at a printing speed of 250 mm / s, and the printing effect is excellent.

[0082] In addition, according to the comparative examples 1-4, with the decrease of the content of lactide in the polylactic acid copolymer, the average segment length of the lactide unit (LLLL) in the copolymer chain decreases from 20 to 5, the T g and the melting point gradually decrease, and the toughness and interlayer bonding force increase. According to the example 4, when the average segment length of the lactide unit (LLLL) in the polymer chain is 5, the elongation at break is as high as 273.1%, which is 49 times of that of pure polylactic acid, and the interlayer bonding force is as high as 412 N, which is 2.4 times of that of pure polylactic acid, showing excellent toughness and interlayer bonding capacity.

[0083] According to the comparative examples 7-10, with the decrease of the content of lactide in the triblock copolymer, the T g and the melting point of the wire change little, especially the melting point can still be kept above 170℃, and the toughness and interlayer bonding force increase. According to the example 10, when the mass fraction of the lactide unit in the triblock copolymer is 80%, the elongation at break can reach 112.5%, which is 20 times of that of pure polylactic acid, and the interlayer bonding force can reach 372 N, which is 2.2 times of that of pure polylactic acid, showing excellent toughness and interlayer bonding capacity. According to the comparative examples 1-12, the toughness and interlayer bonding capacity of the wire prepared from the random copolymer are higher than those of the wire prepared from the triblock copolymer with the same mass fraction.

[0084] Finally, it should be noted that the above-mentioned is only a specific embodiment of the present application. Obviously, the present application is not limited to the above-mentioned embodiment, and there can be many variations. All the variations that can be directly derived or thought from the disclosure of the present application by those skilled in the art should be considered as the protection scope of the present application.

Claims

1. A method for tuning a 3D printing filament based on the sequence structure of the segments, characterized by, is a poly-lactic acid and a poly-lactic acid copolymer with a specific chain segment sequence structure in a mass ratio of 80-95:5-20, which are uniformly blended; and is obtained by melt extrusion granulation and melt extrusion stretching and setting, and is suitable for a poly-lactic acid-based 3D printing wire with a printing speed of ≥250 mm / s. The polylactic acid copolymer with a specific chain segment sequence structure refers to a poly(lactic acid-co-) copolymer formed by ring-opening copolymerization of lactide and caprolactone. co -Caprolactone) random copolymer; in this polylactic acid copolymer, the mass fraction of lactide units is 80~95% and the average segment length is 5~20, and the mass fraction of caprolactone units is 5~20% and the average segment length is 1~2.

2. The method of claim 1, wherein, Specifically comprises the following steps: (1) The poly-lactic acid and the poly-lactic acid copolymer are respectively weighed according to the mass parts, and are uniformly mixed after drying treatment to obtain a blended raw material; (2) The blended raw material is added into a double-screw extruder, and is melt plasticized and extruded to obtain a wire material master batch; (3) The wire material master batch is added into a single-screw extruder, and is melt plasticized, stretched and set, and wound into a wire to obtain a 3D printing wire with a wire diameter of 1.75 mm ± 0.05 mm.

3. The method of claim 2, wherein, The working temperature of the double-screw extruder and the single-screw extruder is 180-230°C.

4. The method of claim 2, wherein, In the blended raw material or the wire material master batch, any one or more of the following auxiliary materials or agents is further added: a chain extender, a nucleating agent, a plasticizer, an antioxidant, an anti-hydrolysis agent and a pigment.

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