A prefabricated plastic track with scaly surface and preparation method thereof

Abstract

The present invention provides a prefabricated plastic track with a scaly surface and a preparation method thereof. The prefabricated plastic track is obtained by spreading surface resin particles on the surface of a film, cooling the surface resin particles after melting, and rolling the surface of the thermoplastic prefabricated plastic track by electron beam irradiation cross-linking. The surface layer is made of PP, light calcium carbonate, asbestos, plasticizer, POE, antioxidant, irradiation cross-linking agent and coupling agent, and the film is made of PP, maleic anhydride grafted SEBS, and maleic anhydride grafted PP. The three-layer structure of the prefabricated plastic track has been processed by hot melt bonding, irradiation cross-linking, etc., and has a scaly surface, which can achieve improved anti-slip value and impact absorption performance.

Description

Technical Field

[0001] The invention belongs to the technical field of runway preparation, and in particular relates to a prefabricated plastic runway with a scaly surface and a preparation method thereof. Background Art

[0002] Traditional prefabricated plastic tracks are usually made of polyurethane glue mixed with EPDM particles. The advent of SEBS-based prefabricated plastic tracks has solved the problems of high cost of traditional plastic tracks, complex rubber vulcanization processing technology, and difficulty in recycling thermosetting materials. However, due to the lack of cross-linking structure inside the SEBS material, the prefabricated plastic track based on SEBS material has problems such as insufficient anti-slip performance and impact absorption performance, which poses a safety hazard when used.

[0003] Chinese patent 202220127423.X provides an anti-skid EPDM plastic track, which circulates air through a drying mechanism to accelerate the evaporation of surface moisture, keep the track dry, and achieve an anti-skid effect. However, the internal structure of the material is simple, and the anti-skid value is low under normal conditions. It requires the help of an external drying mechanism to achieve anti-skid, and is more complicated to use.

[0004] Chinese patent CN2707803Y discloses a composite sports field floor, which is a composite structure composed of a base layer and an anti-skid structure surface layer, which can take into account both resilience and anti-skid properties. However, its multi-layer structure relies on the sticky bonding of adhesives. During long-term outdoor use, due to light aging and other effects, the viscosity will decrease, resulting in weakening of the direct bonding force between layers, causing bulging and other problems, which is not conducive to long-term use. Summary of the invention

[0005] In view of the above problems, the present invention provides a prefabricated plastic track with a scaly surface and a preparation method thereof, in order to solve the problems that the current SEBS-based plastic track surface has weak anti-skid ability, insufficient impact absorption, and unstable interlayer bonding force of the composite prefabricated track. The prefabricated plastic track with a scaly surface consists of a three-layer structure of a surface layer, a middle layer, and a bottom layer. The surface layer is made by melting resin particles, the middle layer is a polyolefin film, and the bottom layer is a prefabricated thermoplastic plastic track. The prepared resin particles are spread on the middle layer of the track, and the molten particles react with the middle layer polyolefin film to form a surface scaly structure, thereby greatly improving the anti-skid performance of the track and forming a strong interlayer bonding force, while not affecting its recyclability.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing a prefabricated plastic track with a scaly surface comprises the following steps:

[0008] (1) Preparing surface resin particles: uniformly mixing the surface raw materials and extruding and granulating them at 160-175° C. through an extruder to obtain surface resin particles;

[0009] The surface layer raw materials include the following raw materials in parts by weight:

[0010] 50-80 parts of PP, 30-50 parts of light calcium carbonate, 5-10 parts of asbestos, 5-10 parts of plasticizer, 10-15 parts of POE, 0.1-1 parts of antioxidant, 2-6 parts of radiation cross-linking agent and 1-2 parts of coupling agent;

[0011] (2) preparing a middle layer polyolefin film: uniformly mixing the middle layer raw materials, extruding them through a casting machine at 160-180° C., and then cooling them to obtain a film;

[0012] The middle layer raw materials include the following raw materials in parts by weight:

[0013] 50-80 parts of PP, 10-20 parts of maleic anhydride grafted SEBS, 10-20 parts of maleic anhydride grafted PP;

[0014] (3) Composite stage of surface layer particles and middle layer film: at 140-160° C., the surface layer resin particles are spread on the surface of the film, the surface layer resin particles are melted and then cooled to obtain a composite precursor; the composite precursor is cross-linked by electron beam irradiation to obtain a composite layer;

[0015] (4) Rolling forming stage: The composite layer is coated on the surface of the thermoplastic prefabricated plastic track, and rolling is performed at 140-160° C. to obtain the prefabricated plastic track with a scaly surface.

[0016] Since the resin particles in the surface layer are melted on the surface of the film in the middle layer and then cooled, the surface of the obtained composite layer has a unique flaky surface.

[0017] Preferably, the plasticizer in step (1) is one or more of epoxidized soybean oil, dioctyl sebacate, trimethylolpropane ester, and triacetin, which is used to improve the plasticity of the system.

[0018] Preferably, the antioxidant described in step (1) is one or more of 2,6-tert-butyl-4-methylphenol, pentaerythritol tetrakis(4-hydroxy-3,5-di-tert-butylphenylpropionate), octadecyl 3,5-di-tert-butyl-4-hydroxyphenylpropionate, triphenyl phosphite or trinonylphenyl phosphite.

[0019] Preferably, the radiation cross-linking agent in step (1) is one or more of triallyl isocyanurate, triallyl cyanurate, trimethallyl isocyanate or trimethylolpropane trimethacrylate.

[0020] Preferably, the coupling agent in step (1) is KH550.

[0021] Preferably, the mixing temperature in step (1) is room temperature, and the mixing time is 6 to 15 minutes.

[0022] Preferably, the extruder described in step (1) is a twin-screw extruder, and the temperature of one zone of the twin-screw extruder is 160°C, the temperature of the head is 165°C, and the temperature of the remaining zones is 175°C.

[0023] Preferably, the casting machine described in step (2) is a casting machine single screw extruder, the extruder temperature is 160-180°C, and the die head temperature is 165°C.

[0024] Preferably, the cooling temperature in step (2) is 30°C.

[0025] Preferably, step (2) further comprises the step of pulling and winding after cooling.

[0026] Preferably, the thermoplastic prefabricated plastic track described in step (4) comprises the following raw materials in parts by weight:

[0027] 10-30 parts of SEBS, 5-15 parts of PP, 10-30 parts of cyclohexane oil and 30-50 parts of light calcium carbonate.

[0028] Preferably, the thermoplastic prefabricated plastic track described in step (4) is prepared by the following method:

[0029] The raw materials of the thermoplastic prefabricated plastic track are mixed uniformly, extruded at 160-175° C. by an extruder, and then cooled by a cold roller to obtain the track.

[0030] Preferably, the extruder is a twin-screw extruder, the temperature of one zone is 160°C, the temperature of the die head is 165°C, and the temperature of the remaining zones is 175°C.

[0031] Preferably, the electron beam cross-linking irradiation in step (3) is performed using an electron accelerator, the electron beam energy is 1 Mev to 4 Mev, the beam current is 10 mA to 50 mA, and the irradiation dose is 40 kGy to 200 kGy.

[0032] The present invention also provides a prefabricated plastic track with a scaly surface prepared by the above method.

[0033] The beneficial effects of the present invention are:

[0034] The prefabricated plastic track with a scaly surface and the preparation method thereof described in the present invention have the following advantages over the existing technology:

[0035] (1) The prefabricated plastic track with a scaly surface of the present invention has a three-layer structure, wherein the surface resin particles contain a certain amount of asbestos and a coupling agent, and the middle polyolefin film contains maleic anhydride grafted SEBS and maleic anhydride grafted PP. The surface resin particles and the middle polyolefin film are cooled by hot melt spraying to obtain a scaly structure. During the hot melt process, the asbestos in the surface resin particles plays a role in initial physical structural support. The coupling agent can not only enhance the binding force between the components inside the resin particles, but also further utilize the amino groups contained in it to react with some maleic anhydride groups contained in the maleic anhydride grafted SEBS and maleic anhydride grafted PP in the middle polyolefin film to undergo addition reaction. At the same time, it is assisted by electron beam irradiation cross-linking. Under the synergistic effect of physical support and multiple chemical bonds, a unique scaly structure is formed.

[0036] (2) After the flaky structure is formed by hot melting, the present invention further uses electron beam irradiation cross-linking technology to simultaneously treat the combined surface resin particles and the middle layer polyolefin film. Electron beam irradiation cross-linking can induce micro-cross-linking of unsaturated bonds. At this time, the irradiation cross-linking agent contained in the surface resin particles and some maleic anhydride groups contained in the maleic anhydride grafted SEBS and maleic anhydride grafted PP in the middle layer polyolefin film can be irradiated cross-linked, that is, certain chemical bonds can be formed inside the surface layer, inside the middle layer, and between the surface layer and the middle layer. The chemical bonds formed by the electron beam irradiation cross-linking work together with the chemical bonds formed by the aforementioned coupling agent to effectively ensure the stability and bonding strength of the flaky surface structure.

[0037] (3) The middle layer polyolefin film of the present invention contains PP, maleic anhydride grafted SEBS and maleic anhydride grafted PP, and the bottom layer SEBS prefabricated plastic track substrate contains SEBS and PP and other substances. The two are combined and formed by hot compressing and rolling. Both contain PP and SEBS structures. The structural similarity ensures good bonding strength. In addition, the PP contained in the surface resin particles can also play a similar good effect with the middle layer polyolefin film.

[0038] (4) The surface resin particles, the middle polyolefin film and the bottom SEBS prefabricated plastic track substrate used in the present invention are all thermoplastic materials, which ensures the overall recyclability. Therefore, the prefabricated plastic track with a scaly surface in the present invention is a fully recyclable plastic track. At the same time, on the one hand, the rough structure of the scaly surface is used to improve the anti-slip performance, and on the other hand, the three-dimensional structure of the scaly surface is used to improve the impact absorption performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a surface optical photograph of the prefabricated plastic track with a scaly surface according to the present invention. DETAILED DESCRIPTION

[0040] The technical scheme of the present invention is described clearly and completely below. The following embodiments are used to illustrate the present invention but not to limit the scope of the present invention.

[0041] In this example, a prefabricated plastic track with a scaly surface and a preparation method thereof are carried out in the following steps:

[0042] Example 1

[0043] (1) Preparation of surface resin particles:

[0044] 70 parts of PP, 40 parts of light calcium carbonate, 8 parts of asbestos, 10 parts of epoxy soybean oil, 12 parts of POE, 0.5 parts of 2,6-tert-butyl-4-methylphenol, 3 parts of triallyl isocyanurate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The melt-blended extruded materials were cooled by water and pelletized to obtain the resin particles.

[0045] (2) Preparation of middle layer polyolefin film:

[0046] Weigh 60 parts of PP, 15 parts of maleic anhydride grafted SEBS, and 15 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, pulling and winding, a polyolefin film is obtained.

[0047] (3) Preparation of middle and surface composite polyolefin films:

[0048] The prepared middle-layer polyolefin film is heated to 150°C, and the surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated with an electron accelerator, and the electron beam energy of the electron accelerator is set to 2.2Mev, the beam current is 30mA, and the irradiation dose is 120kGy. After electron beam irradiation, an irradiation-crosslinked composite layer is obtained.

[0049] (4) Preparation of SEBS-based prefabricated plastic track:

[0050] Weigh 25 parts of SEBS, 10 parts of PP, 30 parts of cyclohexane oil and 35 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0051] (5) Preparation of prefabricated plastic track with scaly surface:

[0052] The bottom SEBS-based prefabricated plastic track is heated to 150° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0053] Example 2

[0054] (1) Preparation of surface resin particles:

[0055] Weigh 50 parts of PP, 30 parts of light calcium carbonate, 5 parts of asbestos, 5 parts of dioctyl sebacate, 10 parts of POE, 0.1 parts of pentaerythritol tetrakis (4-hydroxy-3,5-di-tert-butylphenyl propionate), 2 parts of triallyl cyanurate, and 1 part of coupling agent KH550 by weight. Stir the above raw materials at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch to a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, cool the melt-blended extruded materials over water, and pelletize to obtain the resin particles.

[0056] (2) Preparation of middle layer polyolefin film:

[0057] Weigh 50 parts of PP, 10 parts of maleic anhydride grafted SEBS, and 10 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, pulling and winding, a polyolefin film is obtained.

[0058] (3) Preparation of middle and surface composite polyolefin films:

[0059] The prepared middle layer polyolefin film is heated to 150°C, and the surface resin particles are evenly spread on the surface of the heated middle layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated by an electron accelerator, and the electron beam energy of the electron accelerator is set to 2.2Mev, the beam current is 40mA, and the irradiation dose is 200kGy. After electron beam irradiation, an irradiation cross-linked composite layer is obtained.

[0060] (4) Preparation of SEBS-based prefabricated plastic track:

[0061] Weigh 30 parts of SEBS, 5 parts of PP, 30 parts of cyclohexane oil and 40 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0062] (5) Preparation of prefabricated plastic track with scaly surface:

[0063] The bottom SEBS-based prefabricated plastic track is heated to 150° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0064] Example 3

[0065] (1) Preparation of surface resin particles:

[0066] 80 parts of PP, 50 parts of light calcium carbonate, 10 parts of asbestos, 10 parts of trimethylolpropane ester, 15 parts of POE, 1 part of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid octadecyl, 6 parts of trimethylallyl isocyanate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The melt-blended extruded materials were cooled by water and pelletized to obtain the resin particles.

[0067] (2) Preparation of middle layer polyolefin film:

[0068] Weigh 80 parts of PP, 20 parts of maleic anhydride grafted SEBS, and 20 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, pulling and winding, a polyolefin film is obtained.

[0069] (3) Preparation of middle and surface composite polyolefin films:

[0070] The prepared middle-layer polyolefin film is heated to 140°C, and the surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated with an electron accelerator, and the electron beam energy of the electron accelerator is set to 1 MeV, the beam current is 40 mA, and the irradiation dose is 40 kGy. After electron beam irradiation, an irradiation-crosslinked composite layer is obtained.

[0071] (4) Preparation of SEBS-based prefabricated plastic track:

[0072] Weigh 20 parts of SEBS, 10 parts of PP, 20 parts of cyclohexane oil and 30 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0073] (5) Preparation of prefabricated plastic track with scaly surface:

[0074] The bottom SEBS-based prefabricated plastic track is heated to 150° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0075] Example 4

[0076] (1) Preparation of surface resin particles:

[0077] 80 parts of PP, 40 parts of light calcium carbonate, 5 parts of asbestos, 5 parts of epoxy soybean oil, 12 parts of POE, 0.5 parts of triphenyl phosphite, 3 parts of trimethylolpropane trimethacrylate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The melt-blended extruded materials were cooled by water and pelletized to obtain the resin particles.

[0078] (2) Preparation of middle layer polyolefin film:

[0079] Weigh 60 parts of PP, 20 parts of maleic anhydride grafted SEBS, and 10 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, pulling and winding, a polyolefin film is obtained.

[0080] (3) Preparation of middle and surface composite polyolefin films:

[0081] The prepared middle-layer polyolefin film is heated to 150°C, and the surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated with an electron accelerator, and the electron beam energy of the electron accelerator is set to 4Mev, the beam current is 10mA, and the irradiation dose is 40kGy. After electron beam irradiation, an irradiation-crosslinked composite layer is obtained.

[0082] (4) Preparation of SEBS-based prefabricated plastic track:

[0083] Weigh 10 parts of SEBS, 5 parts of PP, 20 parts of cyclohexane oil and 40 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0084] (5) Preparation of prefabricated plastic track with scaly surface:

[0085] The bottom SEBS-based prefabricated plastic track is heated to 150° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0086] Example 5

[0087] (1) Preparation of surface resin particles:

[0088] 60 parts of PP, 40 parts of light calcium carbonate, 10 parts of asbestos, 10 parts of triacetin, 15 parts of POE, 1 part of trinonylphenyl phosphite, 3 parts of triallyl isocyanurate, 3 parts of trimethylolpropane trimethacrylate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The melt-blended extruded materials were cooled by water and pelletized to obtain the resin particles.

[0089] (2) Preparation of middle layer polyolefin film:

[0090] Weigh 60 parts of PP, 10 parts of maleic anhydride grafted SEBS, and 20 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, pulling and winding, a polyolefin film is obtained.

[0091] (3) Preparation of middle and surface composite polyolefin films:

[0092] The prepared middle-layer polyolefin film is heated to 160°C, and the surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated with an electron accelerator, and the electron beam energy of the electron accelerator is set to 1 MeV, the beam current is 50 mA, and the irradiation dose is 180 kGy. After electron beam irradiation, an irradiation-crosslinked composite layer is obtained.

[0093] (4) Preparation of SEBS-based prefabricated plastic track:

[0094] Weigh 30 parts of SEBS, 15 parts of PP, 10 parts of cyclohexane oil and 50 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the temperature of the head to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0095] (5) Preparation of prefabricated plastic track with scaly surface:

[0096] The bottom SEBS-based prefabricated plastic track is heated to 140° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0097] Example 6

[0098] (1) Preparation of surface resin particles:

[0099] 70 parts of PP, 40 parts of light calcium carbonate, 10 parts of asbestos, 5 parts of epoxy soybean oil, 5 parts of dioctyl sebacate, 12 parts of POE, 0.5 parts of 2,6-tert-butyl-4-methylphenol, 6 parts of trimethylallyl isocyanate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The melt-blended extruded materials were cooled by water and pelletized to obtain the resin particles.

[0100] (2) Preparation of middle layer polyolefin film:

[0101] 70 parts of PP, 15 parts of maleic anhydride grafted SEBS, and 15 parts of maleic anhydride grafted PP were weighed by weight, and the above raw materials were added into a high-speed mixer, and stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added into a single-screw extruder of a casting machine. The extruder temperature was 170°C, and the die head was 165°C. After the melt was extruded, it was cooled on a casting roller to form a film. The temperature of the cooling roller was 30°C. After cooling, pulling and winding, a polyolefin film was obtained.

[0102] (3) Preparation of middle and surface composite polyolefin films:

[0103] The prepared middle layer polyolefin film is heated to 150°C, and the surface resin particles are evenly spread on the surface of the heated middle layer film. The resin particles are melted and then cooled to obtain a composite precursor covered with molten particles. The composite precursor is irradiated by an electron accelerator, and the electron beam energy of the electron accelerator is set to 4Mev, the beam current is 40mA, and the irradiation dose is 200kGy. After electron beam irradiation, an irradiation cross-linked composite layer is obtained.

[0104] (4) Preparation of SEBS-based prefabricated plastic track:

[0105] Weigh 20 parts of SEBS, 15 parts of PP, 25 parts of cyclohexane oil and 40 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0106] (5) Preparation of prefabricated plastic track with scaly surface:

[0107] The bottom SEBS-based prefabricated plastic track is heated to 160° C., the prepared composite layer is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track, sent to a pattern roller for extrusion, cooled and formed, and a prefabricated plastic track with a scaly surface is obtained.

[0108] Comparative Example 1

[0109] Preparation of SEBS-based prefabricated plastic track:

[0110] Weigh 25 parts of SEBS, 10 parts of PP, 30 parts of cyclohexane oil and 35 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0111] Comparative Example 2

[0112] (1) Preparation of surface resin particles:

[0113] 70 parts of PP, 40 parts of light calcium carbonate, 8 parts of asbestos, 10 parts of epoxy soybean oil, 12 parts of POE, 0.5 parts of 2,6-tert-butyl-4-methylphenol, 3 parts of triallyl isocyanurate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The materials extruded by melt blending were cooled by water and pelletized to obtain the resin particles.

[0114] (2) Preparation of middle layer polyolefin film:

[0115] Weigh 60 parts of PP, 15 parts of maleic anhydride grafted SEBS, and 15 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, traction and winding, a polyolefin film is obtained.

[0116] (3) Preparation of middle and surface composite polyolefin films:

[0117] The prepared middle-layer polyolefin film is heated to 150° C., and surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a polyolefin film covered with molten particles.

[0118] (4) Preparation of SEBS-based prefabricated plastic track:

[0119] Weigh 25 parts of SEBS, 10 parts of PP, 30 parts of cyclohexane oil and 35 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0120] (5) Preparation of prefabricated plastic track:

[0121] The bottom SEBS-based prefabricated plastic track is heated to 150°C, and the prepared polyolefin film covered with molten particles is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track. The surface of the track is hot-covered with the above-prepared double-layer polyolefin film, and sent to a pattern roller for extrusion, cooled and formed to obtain a prefabricated plastic track.

[0122] Comparative Example 3

[0123] (1) Preparation of surface resin particles:

[0124] 70 parts of PP, 40 parts of light calcium carbonate, 8 parts of fumed silica, 10 parts of epoxy soybean oil, 12 parts of POE, 0.5 parts of 2,6-tert-butyl-4-methylphenol, 3 parts of triallyl isocyanurate, and 2 parts of coupling agent KH550 were weighed by weight. The above raw materials were stirred at room temperature for 10 minutes to obtain a masterbatch, and the masterbatch was added to a twin-screw extruder, and the temperature of the first zone of the twin-screw extruder was set to 160°C, the head temperature was 165°C, and the temperature of the other zones was 175°C. The materials extruded by melt blending were cooled by water and pelletized to obtain the resin particles.

[0125] (2) Preparation of middle layer polyolefin film:

[0126] Weigh 60 parts of PP, 15 parts of maleic anhydride grafted SEBS, and 15 parts of maleic anhydride grafted PP by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a single-screw extruder of a casting machine, the extruder temperature is 170°C, the die head is 165°C, and the melt is cooled on a casting roller after extrusion to form a film. The temperature of the cooling roller is 30°C. After cooling, traction and winding, a polyolefin film is obtained.

[0127] (3) Preparation of middle and surface composite polyolefin films:

[0128] The prepared middle-layer polyolefin film is heated to 150°C, and the surface resin particles are evenly spread on the surface of the heated middle-layer film. The resin particles are melted and then cooled to obtain a polyolefin film covered with molten particles. The polyolefin film is irradiated with an electron accelerator, and the electron beam energy of the electron accelerator is set to 2.2Mev, the beam current is 30mA, and the irradiation dose is 120kGy. After electron beam irradiation, an irradiated cross-linked polyolefin film is obtained.

[0129] (4) Preparation of SEBS-based prefabricated plastic track:

[0130] Weigh 25 parts of SEBS, 10 parts of PP, 30 parts of cyclohexane oil and 35 parts of light calcium carbonate by weight, add the above raw materials into a high-speed mixer, stir at room temperature for 10 minutes to obtain a masterbatch, add the masterbatch into a twin-screw extruder, set the temperature of the first zone of the twin-screw extruder to 160°C, the head temperature to 165°C, and the temperature of the other zones to 175°C, after melt extrusion, cool it down with a cold roller to obtain a SEBS-based prefabricated plastic runway, and the temperature of the cold roller is 30°C.

[0131] (5) Preparation of prefabricated plastic track:

[0132] The bottom SEBS-based prefabricated plastic track is heated to 150°C, and the prepared polyolefin film covered with molten particles is hot-coated on the surface of the bottom SEBS-based prefabricated plastic track. The surface of the track is hot-covered with the above-prepared double-layer polyolefin film, and sent to a pattern roller for extrusion, cooled and formed to obtain a prefabricated plastic track.

[0133] Example 7

[0134] This example performs performance tests on the runway samples prepared in each example to demonstrate the performance of the runway. The test is based on the standard manual for track and field facilities. The test results are shown in Table 1:

[0135] Table 1 Performance test results of the plastic track prepared in each embodiment

[0136] Test track Shock absorption (%) Anti-slip value (BPN20℃) Example 1 46.3 67 Example 2 43.7 58 Example 3 41.2 62 Example 4 43.9 57 Example 5 42.3 60 Example 6 45.4 52 Comparative Example 1 34.8 35 Comparative Example 2 38.1 44 Comparative Example 3 35.6 41

[0137] It can be seen from Table 1 that the prefabricated plastic tracks prepared in Examples 1 to 6 are prepared by spreading surface resin particles on the surface of a film, melting the surface resin particles, cooling them, cross-linking them with electron beam radiation, and then rolling them on the surface of the thermoplastic prefabricated plastic track. The impact absorption and anti-slip values ​​are higher than those of Example 1 which has not undergone any treatment. At the same time, Example 2 which does not undergo radiation cross-linking and Example 3 in which the surface resin particles use ordinary filler gas-phase silica instead of asbestos cannot achieve the performance effect of the present invention.

[0138] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, which means that all such replacements and modifications within the scope of the present invention are included in the attached claims.

Claims

1. A method for preparing a prefabricated plastic track with a scaly surface, It is characterized in that The steps include: (1) Preparing surface resin particles: uniformly mixing the surface raw materials and extruding and granulating them at 160-175° C. through an extruder to obtain surface resin particles; The surface layer raw materials include the following raw materials in parts by weight: 50-80 parts of PP, 30-50 parts of light calcium carbonate, 5-10 parts of asbestos, 5-10 parts of plasticizer, 10-15 parts of POE, 0.1-1 parts of antioxidant, 2-6 parts of radiation cross-linking agent and 1-2 parts of coupling agent; (2) preparing a middle layer polyolefin film: uniformly mixing the middle layer raw materials, extruding them through a casting machine at 160-180° C., and then cooling them to obtain a film; The middle layer raw materials include the following raw materials in parts by weight: 50-80 parts of PP, 10-20 parts of maleic anhydride grafted SEBS, 10-20 parts of maleic anhydride grafted PP; (3) Composite stage of surface layer particles and middle layer film: at 140-160° C., the surface layer resin particles are spread on the surface of the film, the surface layer resin particles are melted and then cooled to obtain a composite precursor; the composite precursor is cross-linked by electron beam irradiation to obtain a composite layer; (4) Rolling forming stage: The composite layer is coated on the surface of the thermoplastic prefabricated plastic track, and rolling is performed at 140-160° C. to obtain the prefabricated plastic track with a scaly surface.

2. The preparation method according to claim 1, It is characterized in that The plasticizer described in step (1) is one or more of epoxy soybean oil, dioctyl sebacate, trimethylolpropane ester, and triacetin.

3. The preparation method according to claim 1, It is characterized in that The antioxidant described in step (1) is one or more of 2,6-tert-butyl-4-methylphenol, pentaerythritol tetrakis(4-hydroxy-3,5-di-tert-butylphenylpropionate), octadecyl 3,5-di-tert-butyl-4-hydroxyphenylpropionate, triphenyl phosphite or trinonylphenyl phosphite.

4. The preparation method according to claim 1, It is characterized in that The radiation cross-linking agent described in step (1) is one or more of triallyl isocyanurate, triallyl cyanurate, trimethallyl isocyanate or trimethylolpropane trimethacrylate.

5. The preparation method according to claim 1, It is characterized in that The coupling agent described in step (1) is KH550.

6. The preparation method according to claim 1, It is characterized in that The cooling temperature in step (2) is 30°C.

7. The preparation method according to claim 1, It is characterized in that The electron beam cross-linking irradiation described in step (3) is carried out using an electron accelerator, with an electron beam energy of 1Mev to 4Mev, a beam current of 10mA to 50mA, and an irradiation dose of 40kGy to 200kGy.

8. The preparation method according to claim 1, It is characterized in that The thermoplastic prefabricated plastic track described in step (4) comprises the following raw materials in parts by weight: 10-30 parts of SEBS, 5-15 parts of PP, 10-30 parts of cyclohexane oil and 30-50 parts of light calcium carbonate.

9. The preparation method according to claim 8, It is characterized in that The thermoplastic prefabricated plastic track described in step (4) is prepared by the following method: The raw materials of the thermoplastic prefabricated plastic track are mixed uniformly, extruded at 160-175° C. by an extruder, and then cooled by a cold roller to obtain the track.

10. A prefabricated plastic track with a scaly surface prepared by the preparation method according to any one of claims 1 to 9.

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