A carrier roller body composition, a carrier roller body and a method of making the same

Abstract

The present application relates to a kind of roller body compositions of carrier roller, carrier roller and its preparation method, the composition includes: 100 mass parts polyvinyl chloride, 3~12 mass parts antistatic agent and other auxiliary agents;The antistatic agent includes conductive carbon black and multi-walled carbon nanotube;Wherein, the specific surface area of the conductive carbon black is ≥700m 2 / g, the aspect ratio of the multi-walled carbon nanotube is ≥1500.The carrier roller body composition of an embodiment of the present application, by using conductive carbon black and multi-walled carbon nanotube with specific structure as antistatic agent, can make the carrier roller prepared still has better antistatic property after wearing, so that its antistatic property is more durable.

Description

Technical Field

[0001] This invention relates to idler roller bodies, and more particularly to the preparation of an idler roller body for underground mining transportation in coal mines and other underground mines. Background Technology

[0002] In underground mining transportation, such as in coal mines, the roller-belt system is a crucial method for mineral transport. Polymer products used in underground coal mine transportation must not only meet various mechanical performance requirements but also satisfy flame retardancy and antistatic properties. This is primarily because polymer-made mining rollers generate static electricity during friction with the conveyor belt, which can pose a significant safety hazard if it coexists with coalbed methane in underground mining operations. Therefore, according to the MT113 standard, the surface resistivity of underground polymer products must be less than or equal to 3 × 10⁻⁶. 8 Ω.

[0003] Furthermore, unlike other polymer products used in underground mining, the continuous nature of coal transportation means that the idler rollers run continuously with the conveyor belt. During operation, the idler rollers rub against the conveyor belt, causing the outermost edge of the roller body to wear down slowly. Therefore, polymer idler rollers used underground require permanent antistatic properties and long-lasting antistatic performance.

[0004] Some existing idler roller products use PVC antistatic agents, which are migratory antistatic agents. These small-molecule antistatic agents migrate to the polymer surface over a certain period (a few days) to achieve the surface resistivity required for mining applications. Although the accumulation of migratory surface antistatic agents on the product surface can make the idler roller meet the antistatic requirements, the roller surface wears down during transportation due to friction with the belt, resulting in a lower content of newly generated surface antistatic agents. Therefore, the antistatic grade cannot meet the MT113 requirement, and the surface resistivity is greater than 3 × 10⁻⁶. 8 Ω. Therefore, although PVC idler rollers can meet the antistatic requirements at the beginning of operation, their antistatic performance will decrease after continuous operation and friction wear, which can easily lead to significant safety hazards. Summary of the Invention

[0005] To overcome at least one of the defects of the prior art, in a first aspect, one embodiment of the present invention provides an idler roller composition comprising: 100 parts by weight of polyvinyl chloride, 3-12 parts by weight of an antistatic agent and other additives; wherein the antistatic agent comprises conductive carbon black and multi-walled carbon nanotubes; wherein the specific surface area of ​​the conductive carbon black is ≥700 m². 2 / g, wherein the aspect ratio of the multi-walled carbon nanotubes is ≥1500.

[0006] Secondly, one embodiment of the present invention provides a method for preparing an idler roller body, comprising the following steps:

[0007] Provide a conductive masterbatch; and

[0008] The conductive masterbatch is co-extruded with polyvinyl chloride and other additives;

[0009] The conductive masterbatch includes an antistatic agent and a compatibilizer, wherein the antistatic agent includes conductive carbon black and multi-walled carbon nanotubes.

[0010] Thirdly, one embodiment of the present invention provides an idler roller body, which is prepared by the above-described composition or the above-described method.

[0011] The idler roller composition of one embodiment of the present invention, by using conductive carbon black and multi-walled carbon nanotubes with specific structures as antistatic agents, enables the prepared idler roller to still have better antistatic properties after wear, making its antistatic properties more durable. Detailed Implementation

[0012] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the description herein is for illustrative purposes only and not intended to limit the present invention.

[0013] One embodiment of the present invention provides a roller body (or roller cylinder) composition, comprising: 100 parts by weight of polyvinyl chloride, 3-12 parts by weight of an antistatic agent and other additives; the antistatic agent includes conductive carbon black and multi-walled carbon nanotubes; wherein the specific surface area of ​​the conductive carbon black is ≥700 m². 2 / g, the aspect ratio of multi-walled carbon nanotubes is ≥1500.

[0014] In one embodiment, the specific surface area of ​​the conductive carbon black can be 700–1200 m². 2 / g, and can be further increased to 850-1000m 2 / g, for example 800m 2 / g、850m 2 / g、900m 2 / g, 1000m 2 / g、1100m 2 / g; The average particle size of conductive carbon black can be 20-50nm, for example 25nm, 30nm, 35nm, 40nm, 45nm.

[0015] In one embodiment, the particle size D50 of the multi-walled carbon nanotubes can be 15–30 μm, such as 20 μm, 25 μm, or 30 μm; the diameter of the multi-walled carbon nanotubes can be 2–10 nm, such as 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, or 9 nm.

[0016] In one embodiment, the aspect ratio of the multi-walled carbon nanotubes can be 1500 to 15000, and more specifically 6300 to 15000, for example 2000, 2500, 3000, 3500, 4000, 5000, 6000, 8000, 10000, 12000, and 14000.

[0017] In one embodiment, the antistatic agent comprises m1 parts by mass of conductive carbon black and m2 parts by mass of multi-walled carbon nanotubes, 8 ≤ m1 + 5m2, and further 8 ≤ m1 + 5m2 ≤ 16; m1 can be, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, and m2 can be, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11.

[0018] In one embodiment, the degree of polymerization of polyvinyl chloride can be 900 to 1100, more specifically 950 to 1050, for example 1000.

[0019] In one embodiment, other additives include one or more of toughening agents, compatibilizers, nano-calcium carbonate, and stabilizers.

[0020] In one embodiment, the toughening agent includes one or more of methyl methacrylate-butadiene-styrene copolymer (MBS) and acrylate copolymer (ACR).

[0021] In one embodiment, the compatibilizer may be chlorinated polyethylene (CPE); further, the chlorine content of chlorinated polyethylene may be 30-40 wt%, more particularly 34-36 wt%, for example 32 wt%, 35 wt%, or 38 wt%.

[0022] In one embodiment, the average particle size of the nano-calcium carbonate can be 10-100 nm, and more preferably 20-50 nm, such as 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 60 nm, 70 nm, 80 nm, or 90 nm.

[0023] In one embodiment, the stabilizer may be a metal soap stabilizer, or more specifically a calcium-zinc stabilizer.

[0024] In one embodiment, the idler roller composition comprises 100 parts by weight of polyvinyl chloride, 3 to 12 parts by weight of antistatic agent, 10 to 20 parts by weight of toughening agent, 10 to 20 parts by weight of compatibilizer, 2 to 10 parts by weight of nano-calcium carbonate, and 3 to 10 parts by weight of stabilizer.

[0025] In one embodiment, the polyvinyl chloride (PVC) comprises 100 parts by weight, and the sum of the toughening agent and compatibilizer is ≤30 parts by weight, further 20-30 parts by weight, and even further 25-30 parts by weight. When the sum of the toughening agent and compatibilizer is ≤30 parts by weight, the modulus of the formed roller material can reach 1900 MPa or higher; when the sum of the compatibilizer and toughening agent is greater than 30 parts by weight, the larger the sum, the lower the modulus; for example, when the sum of the toughening agent and compatibilizer is 40 parts by weight, the modulus of the obtained roller material is only about 1700 MPa.

[0026] One embodiment of the present invention provides a method for preparing an idler roller body, comprising the following steps:

[0027] Provide a conductive masterbatch; and

[0028] The conductive masterbatch is co-blended and extruded with polyvinyl chloride and other additives to obtain the roller body material;

[0029] The conductive masterbatch includes an antistatic agent and a compatibilizer. The antistatic agent includes conductive carbon black and multi-walled carbon nanotubes.

[0030] In one embodiment, the aforementioned roller material is added to a twin-screw extruder and extruded to obtain the idler roller body (e.g., with a diameter of...). The roller body can be cut to a specified length (e.g., 530mm); furthermore, end caps and idler bearings are fitted onto both ends of the roller body to produce an idler roller.

[0031] The preparation method of the idler roller body according to one embodiment of the present invention uses polyvinyl chloride, conductive carbon black, multi-walled carbon nanotubes, and other additives that are subject to the foregoing limitations.

[0032] In one embodiment, conductive carbon black, multi-walled carbon nanotubes, and a compatibilizer are co-extruded to obtain conductive masterbatch. Further, the conductive carbon black, multi-walled carbon nanotubes, and compatibilizer can be added to a high-speed mixer and mixed for 5–10 minutes. The resulting first mixture is then extruded through a twin-screw extruder to obtain the conductive masterbatch. The high-speed mixer can operate at speeds of 1500–2000 rpm, such as 1600 rpm, 1700 rpm, 1800 rpm, or 1900 rpm. The twin-screw extruder can have a length-to-diameter ratio greater than 30, such as 40. The twin-screw extruder can operate at temperatures of 160–190°C, such as 170°C or 180°C.

[0033] In one embodiment, polyvinyl chloride, conductive masterbatch, and other additives are added to a high-speed mixer and mixed for 5-10 minutes. The resulting second mixture is then extruded and pelletized using a twin-screw extruder to obtain roll body material. The high-speed mixer can operate at 1500-2000 rpm, for example, 1600 rpm, 1700 rpm, 1800 rpm, or 1900 rpm. The twin-screw extruder can have a length-to-diameter ratio greater than 30, for example, 40. The twin-screw extruder can operate at 160-190°C, for example, 170°C or 180°C.

[0034] In one embodiment, the modulus of the roller material (or idler roller body) is ≥1900MPa, and the notched impact strength is ≥10kJ / m. 2 Surface resistivity ≤3×10 8 Ω.

[0035] One embodiment of the present invention provides an idler roller body, which is prepared by the above-described composition and / or the above-described method.

[0036] In one embodiment, the surface resistivity of the idler roller body is less than 3 × 10⁻⁶. 8 Ω, the instantaneous surface resistivity after 0.1 mm of surface wear removal is still less than 3 × 10 Ω. 8 Ω has long-lasting and stable antistatic properties.

[0037] To achieve antistatic properties, existing PVC-based idler rollers either use migratory surface antistatic agents or non-migratory conductive systems such as high-dosage superconducting carbon black. Idler rollers made with migratory antistatic agents exhibit significantly deteriorated surface antistatic properties after prolonged continuous operation, easily leading to the accumulation of surface charge and posing a considerable safety hazard. Conversely, using high-dosage superconducting carbon black results in poor mechanical properties of the finished product.

[0038] The idler roller composition of one embodiment of the present invention uses multi-walled carbon nanotubes with a specific structure (e.g., high aspect ratio multi-walled carbon nanotubes) and conductive carbon black as antistatic agents, which can achieve long-term non-migratory antistatic properties of the idler roller, solving the problem of charge accumulation during continuous operation of the idler roller and ensuring its continuous and safe operation. In addition, the high aspect ratio multi-walled carbon nanotubes can connect discrete conductive carbon black nanoparticles in series to form conductive pathways, which greatly reduces surface resistance and reduces the amount of carbon black added. This allows the idler roller to not only meet the requirements of long-term flame retardant and antistatic properties, but also possess mechanical properties such as high rigidity and high toughness.

[0039] The idler roller composition of one embodiment of the present invention is suitable for the preparation of idler rollers for coal mine transportation.

[0040] The present invention discloses a method for preparing an idler roller body by pre-dispersing an antistatic agent in the preparation of a conductive masterbatch, which can improve the antistatic performance of the prepared idler roller body; in particular, it can achieve better antistatic performance with a smaller amount of antistatic agent, thereby reducing the manufacturing cost of the idler roller body, and can also maintain the relevant mechanical properties at a high level.

[0041] In one embodiment of the present invention, the idler roller body uses inexpensive conductive carbon black with good conductivity as the main conductive agent, and multi-walled carbon nanotubes with a high aspect ratio as the secondary conductive agent to further connect and improve the conductive network. The combination of conductive carbon black and multi-walled carbon nanotubes can produce a significant synergistic effect, greatly reducing the amount of carbon black used. In addition, the antistatic agent is pre-dispersed through conductive masterbatch during the preparation process, which can further reduce the amount of antistatic agent used, and also greatly benefit the mechanical properties of the idler roller body. Therefore, the idler roller body of one embodiment of the present invention can not only solve the antistatic hazards caused by continuous operation of downhole idlers, but also overcome the problem of poor mechanical properties of antistatic idlers.

[0042] The idler roller body of one embodiment of the present invention has long-lasting flame retardancy and antistatic properties, as well as high rigidity and high toughness.

[0043] The following describes, in conjunction with embodiments, a roller body according to an embodiment of the present invention and its preparation. Unless otherwise specified, all raw materials used are commercially available.

[0044] Example 1

[0045] S1: Mix 5 parts by mass of conductive carbon black A, 1 part by mass of multi-walled carbon nanotubes A and 15 parts by mass of compatibilizer CPE in a high-speed mixer for 10 minutes at a speed of 2000 rpm; then add the resulting first mixture to a twin-screw extruder for extrusion to obtain a pre-dispersed conductive masterbatch; wherein the temperature of the twin-screw extruder is set to 170℃ and the length-to-diameter ratio is 40.

[0046] S2: The above-mentioned pre-dispersed conductive masterbatch, 100 parts by weight of polyvinyl chloride, 15 parts by weight of toughening agent MBS, 10 parts by weight of nano calcium carbonate and 5 parts by weight of calcium zinc stabilizer are added to a high-speed mixer for mixing. The mixing time is 10 min and the speed of the high-speed mixer is 2000 rpm. Then the resulting second mixture is added to a twin-screw extruder for extrusion to obtain roller material. The temperature of the twin-screw extruder is set to 170℃ and the length-to-diameter ratio is 40.

[0047] S3: The obtained roller body material is added to a twin-screw extruder for extrusion molding to obtain the idler roller body.

[0048] Among them, the specific surface area of ​​conductive carbon black A (CB-A) is 850 m². 2 / g, with a particle size of 25nm; the average D50 size of multi-walled carbon nanotubes A (MWCNT-A) is 20um, the nanotube diameter is 5nm, and the aspect ratio is 4000.

[0049] Example 1-1

[0050] This embodiment uses the same raw materials and methods as Example 1 to prepare the roller body, the only difference being that the amount of conductive carbon black A is 1.5 parts by mass and the amount of multi-walled carbon nanotubes A is 1.5 parts by mass.

[0051] Examples 1-2

[0052] This embodiment uses the same raw materials and methods as Example 1 to prepare the roller body, the only difference being that: the amount of conductive carbon black A is 11 parts by mass, the amount of multi-walled carbon nanotubes A is 1 part by mass, and the total amount of antistatic agent is 12 parts by mass.

[0053] Example 2

[0054] This embodiment uses essentially the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that the specific surface area of ​​the conductive carbon black used is 750 m². 2 / g, with an average particle size of 32nm.

[0055] Example 2-1

[0056] This embodiment uses essentially the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that the conductive carbon black used has a specific surface area of ​​1000 m². 2 / g, with an average particle size of 20nm.

[0057] Example 3

[0058] This embodiment uses the same raw materials and methods as Example 1 to prepare the roller body, the only difference being that the average D50 size of the multi-walled carbon nanotubes used is 30um, the nanotube diameter is 2nm, and the aspect ratio is 15000.

[0059] Example 3-1

[0060] This embodiment uses the same raw materials and methods as Example 1 to prepare the roller body, the only difference being that the average D50 size of the multi-walled carbon nanotubes used is 19um, the nanotube diameter is 3nm, and the aspect ratio is 6300.

[0061] Example 4

[0062] This embodiment uses the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that: the amount of conductive carbon black A is 3 parts by mass, the amount of compatibilizer CPE is 10 parts by mass, the amount of nano calcium carbonate is 5 parts by mass, and the amount of calcium zinc stabilizer is 3 parts by mass.

[0063] Example 5

[0064] This embodiment uses the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that: the amount of toughening agent MBS is 20 parts by mass, and the amount of compatibilizer CPE is 20 parts by mass.

[0065] Comparative Example 1

[0066] The raw materials used in this example are the same as those in Example 1, and the process steps are as follows:

[0067] All materials were added together and mixed in a high-speed mixer for 10 minutes at a speed of 2000 rpm. The resulting mixture was then extruded in a twin-screw extruder to produce roll material. The temperature of the twin-screw extruder was set to 170°C and the length-to-diameter ratio was 40.

[0068] Comparative Example 2

[0069] This example uses essentially the same raw materials and methods as Example 1 to prepare the roller body, with the only difference being that the amount of conductive carbon black A is 1 part by mass and the amount of multi-walled carbon nanotubes A is 1 part by mass.

[0070] Comparative Example 2-1

[0071] This example uses essentially the same raw materials and methods as Example 1 to prepare the idler roller body, with the only difference being that: the amount of conductive carbon black A is 3 parts by mass, the amount of multi-walled carbon nanotubes A is 10 parts by mass, and the total amount of antistatic agent is 13 parts by mass.

[0072] Comparative Example 3

[0073] This example uses essentially the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that the conductive carbon black B and multi-walled carbon nanotubes B used have different structures than conductive carbon black A and multi-walled carbon nanotubes A; the specific surface area of ​​conductive carbon black B (CB-B) is 400 m². 2 / g, the average D50 size of multi-walled carbon nanotubes B (MWCNT-B) is 5.8um, the nanotube diameter is 5nm, and the aspect ratio is 1160.

[0074] Comparative Example 4

[0075] This example uses essentially the same raw materials and methods as Example 1 to prepare the idler roller body, the only difference being that an equal amount of migratory antistatic agent SAS93 is used to replace conductive carbon black A.

[0076] The roller materials prepared in each embodiment and comparative example were subjected to relevant tests. The specific methods are as follows, and the results are shown in Table 1.

[0077] Performance testing

[0078] Surface resistance test: The roller material was molded at 180℃ and 200 bar for 5 minutes to prepare an antistatic test sample with a thickness of 1 mm. The sample was left to stand at 25℃ and 65% humidity for 24 hours, and then the surface resistance 1 of the sample after constant temperature and humidity was tested using a Keithley 6517B at an ambient temperature of 25℃ and an ambient humidity of 50%. The above sample was subjected to friction and wear for 10,000 cycles at 25℃ using a Taber tribometer. After the test, the sample was not subjected to constant temperature and humidity, and the surface resistance 2 of the sample was directly tested using a Keithley 6517B at an ambient temperature of 25℃ and an ambient humidity of 50%. Surface resistance 2 can reflect the surface resistance of the newly formed surface of the idler roller during the wear process.

[0079] Notched impact strength test: The roller material was molded at 180℃ and 200 bar for 5 minutes to prepare a sample with a thickness of 4 mm. Then the sample was cut into a shape of 4 mm*10 mm*100 mm, and a 2 mm thick V notch was punched in the middle of the sample. After the sample was kept at 23℃ and 50% relative humidity for 24 hours, the notched impact strength was tested.

[0080] Modulus test: The roller material was molded at 180℃ and 200 bar for 5 minutes to prepare a sample with a thickness of 4 mm. The sample was then cut into a shape of 4 mm * 10 mm * 100 mm, and then the sample was kept at 23℃ and 50% relative humidity for 24 hours before the modulus was tested.

[0081] Flame retardancy test: The flame retardancy characteristics of the samples were tested according to the national standard GB / T2408-2008.

[0082] Table 1

[0083]

[0084]

[0085] Comparing Examples 1, 1-1, 1-2, Comparative Example 2, and Comparative Example 2-1, it can be seen that, under the same conditions, the amount of antistatic agent (the sum of conductive carbon black and multi-walled carbon nanotubes) in Examples 1, 1-1, and 1-2 is in the range of 3 to 12 parts by mass, while the amount of antistatic agent in Comparative Examples 2 and 2-1 is 2 parts by mass and 13 parts by mass, respectively. According to the data in Table 1, the surface resistivity of the idler rollers in Examples 1, 1-1, and 1-2 is less than 3 × 10⁻⁶ before and after wear. 8The required Ω value indicates long-lasting antistatic properties and good mechanical properties; however, the surface resistance of the idler roller in Comparative Example 2 does not meet the requirement of being less than 3 × 10⁻⁶. 8 The surface resistance of Comparative Example 2-1 meets the requirement of being less than 3 × 10 Ω; 8 It meets the requirements of Ω, but its notch impact strength is too small.

[0086] Therefore, in the composition of one embodiment of the present invention, when the amount of polyvinyl chloride is 100 parts by mass and the amount of antistatic agent is 3 to 12 parts by mass, the resulting idler roller body can achieve both good antistatic performance and maintain the relevant mechanical properties at a high level.

[0087] Comparing Example 1 and Comparative Example 3, the difference lies in the specific types of conductive carbon black and multi-walled carbon nanotubes used. Example 1 uses conductive carbon black with a specific surface area of ​​850 m². 2 / g, the aspect ratio of the multi-walled carbon nanotubes is 4000; the specific surface area of ​​the conductive carbon black used in Comparative Example 3 is 400m². 2 / g, the aspect ratio of the multi-walled carbon nanotubes is 1160. According to the results in Table 1, the surface resistivity of the idler roller in Comparative Example 3 does not meet the requirement of being less than 3 × 10⁻⁶ g. 8 The requirement of Ω. Therefore, the specific surface area of ​​the conductive carbon black in one embodiment of the present invention is preferably ≥700m². 2 / g, the aspect ratio of multi-walled carbon nanotubes is preferably ≥1500.

[0088] Furthermore, referring to the results in Table 1, it can be seen that, compared to Example 2, the roller bodies of Examples 1 and 2-1 exhibit superior antistatic and mechanical properties. Therefore, the specific surface area of ​​the conductive carbon black is preferably 850–1000 m². 2 / g.

[0089] Furthermore, referring to the results in Table 1, it can be seen that the roller bodies of Examples 3 and 3-1 have better antistatic and mechanical properties compared to Example 1. Therefore, the aspect ratio of the multi-walled carbon nanotubes is preferably 6300-15000.

[0090] Comparative Example 4 used the migratory antistatic agent SAS93 to replace conductive carbon black A to prepare the idler roller body. According to the results in Table 1, the surface resistivity of the roller body in Comparative Example 4, before wear, was 1 (2.9 × 10⁻⁶). 7 It can satisfy less than 3×10 8 The requirement is Ω. However, the newly generated surface resistance after wear is 2 (8.2 × 10⁻⁶). 9 The above requirements cannot be met, which means that the surface of the roller cannot maintain long-term antistatic properties.

[0091] Comparing Example 1 and Comparative Example 1, it can be seen that Comparative Example 1 did not pre-disperse the antistatic agent during the preparation of the idler roller body. According to the results in Table 1, the surface resistivity of the idler roller body of Comparative Example 1 does not meet the requirement of being less than 3 × 10⁻⁶. 8 The required Ω resistance is significantly higher than that of Example 1. Therefore, by pre-dispersing the antistatic agent during the preparation of the idler roller body, a lower surface resistance can be achieved with a smaller amount of antistatic agent, reducing the antistatic agent content in the idler roller body and thus helping to maintain its mechanical properties.

[0092] In Example 1, the sum of the toughening agent and compatibilizer was 30 parts by mass, and in Example 5, the sum of the toughening agent and compatibilizer was 40 parts by mass. According to the results in Table 1, the modulus of the idler roller body of Example 1 (1978 MPa) is significantly greater than that of Example 5 (1738 MPa). Furthermore, the modulus of the idler roller body of Example 4, where the sum of the toughening agent and compatibilizer was 25 parts by mass (2054 MPa), was also significantly greater than that of Example 5. Therefore, in the idler roller body composition of one embodiment of the present invention, when the polyvinyl chloride is 100 parts by mass, the sum of the toughening agent and compatibilizer is preferably ≤30 parts by mass, more preferably 20-30 parts by mass, and even more preferably 25-30 parts by mass.

[0093] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.

[0094] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.

Claims

1. A method for preparing an idler roller body, comprising preparing an idler roller body using an idler roller body composition, wherein the idler roller body composition comprises: The composition comprises 100 parts by weight of polyvinyl chloride, 3-12 parts by weight of antistatic agent, 10-20 parts by weight of toughening agent, 10-20 parts by weight of compatibilizer, 2-10 parts by weight of nano-calcium carbonate, and 3-10 parts by weight of stabilizer; wherein the antistatic agent includes conductive carbon black and multi-walled carbon nanotubes; wherein the specific surface area of ​​the conductive carbon black is ≥700 m² / g. 2 / g, wherein the aspect ratio of the multi-walled carbon nanotubes is ≥1500; the sum of the mass of the toughening agent and the compatibilizer is ≤30 parts by mass, wherein the toughening agent includes one or more of methyl methacrylate-butadiene-styrene copolymer and acrylate copolymers, and the compatibilizer is chlorinated polyethylene; the antistatic agent includes m1 parts by mass of the conductive carbon black and m2 parts by mass of the multi-walled carbon nanotubes, 8≤m1+5m2≤10; The preparation method includes the following steps: Provide a conductive masterbatch; and The conductive masterbatch is co-extruded with the polyvinyl chloride, the toughening agent, the nano-calcium carbonate, and the stabilizer. The conductive masterbatch includes the antistatic agent and the compatibilizer.

2. The preparation method according to claim 1, wherein, The specific surface area of ​​the conductive carbon black is 700–1200 m². 2 / g, wherein the aspect ratio of the multi-walled carbon nanotubes is 1500–15000; and / or, The conductive carbon black has an average particle size of 20–50 nm; and / or, The particle size D50 of the multi-walled carbon nanotubes is 15–30 μm; and / or, The diameter of the multi-walled carbon nanotubes is 2–10 nm.

3. The preparation method according to claim 1, wherein, The specific surface area of ​​the conductive carbon black is 850–1000 m². 2 / g; and / or, The aspect ratio of the multi-walled carbon nanotubes is 6300 to 15000.

4. The preparation method according to claim 1, wherein, The degree of polymerization of the polyvinyl chloride is 900 to 1100.

5. The preparation method according to claim 1, wherein, The degree of polymerization of the polyvinyl chloride is 950 to 1050.

6. The preparation method according to claim 1, wherein, The combined mass of the toughening agent and the compatibilizer is 20-30 parts by mass; and / or, The average particle size of the nano-calcium carbonate is 10–100 nm; and / or, The stabilizer is a metal soap stabilizer.

7. The preparation method according to claim 6, wherein, The combined mass of the toughening agent and the compatibilizer is 25-30 parts by mass; and / or, The average particle size of the nano-calcium carbonate is 20–50 nm; and / or, The stabilizer is a calcium-zinc stabilizer.

8. The preparation method according to claim 1, wherein, The conductive masterbatch is prepared by co-extrusion of the conductive carbon black, the multi-walled carbon nanotubes and the compatibilizer. And / or, The polyvinyl chloride, the conductive masterbatch, the toughening agent, the nano-calcium carbonate, and the stabilizer are added to a high-speed mixer and mixed for 5-10 minutes. The resulting second mixture is then extruded through a twin-screw extruder.

9. The preparation method according to claim 8, wherein, The high-speed mixer has a speed of 1500-2000 rpm, the twin-screw extruder has a length-to-diameter ratio greater than 30, and the twin-screw extruder has a temperature of 160-190℃.

10. An idler roller body, prepared by any one of claims 1 to 9.

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