Manufacturing process of polymer plastic product

Abstract

The invention relates to the technical field of plastic manufacturing processes, in particular to a manufacturing process of a polymer plastic product, which comprises the following steps: preparing ultra-high molecular weight polyethylene as a main raw material which further comprises a pigment, a heat stabilizer, an antioxidant, a plasticizer and a light stabilizer according to a preset formula ratio, performing particle size screening on the raw materials, and then drying to obtain the polymer plastic product. The preparation method comprises the following steps: drying raw materials, ensuring the purity and uniformity of the raw materials, weighing the dried raw materials, adding the weighed raw materials into a mixing device, mixing, uniformly mixing, uniformly adding the raw materials into an extruder, carrying out melt extrusion, controlling the temperature of each section of the extruder, preventing the material from cracking, adding a viscosity modifier during extrusion, and improving the melt flow rate. The prepared plastic product has ultra-high molecular weight, is suitable for various high-end fields, adapts to complex use environments, and reduces the material processing difficulty.

Description

Technical Field

[0001] The invention relates to the technical field of plastic manufacturing technology, in particular to a manufacturing process of polymer plastic products. Background Art

[0002] Ultra-high molecular weight polyethylene is used in many high-end fields and has very good market prospects. Among plastics, the wear resistance of this material exceeds that of ordinary plastics by several times, and it has excellent performance in friction, corrosion resistance, impact resistance and other properties.

[0003] Therefore, a process suitable for the production of the above materials is needed. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a manufacturing process of a polymer plastic product. In order to achieve the above object, the present invention adopts the following technical solutions: A manufacturing process for a polymer plastic product comprises the following steps: Step S1, preparing ultra-high molecular weight polyethylene as the main raw material, and the raw materials also include pigments, heat stabilizers, antioxidants and light stabilizers; Step S2, according to a preset formula ratio, the raw materials are screened for particle size and then dried to ensure the purity and uniformity of the raw materials, the dried raw materials are weighed, and then put into a mixing device for mixing; Step S3, after uniform mixing, the raw materials are uniformly put into an extruder, and melt-extruded into a mold for forming; Step S4, the molded plastic product is cooled by either air cooling or natural cooling.

[0005] Optionally, in one embodiment of the present invention, in step S1, ultra-high molecular weight polyethylene is prepared using β-TiCl3 / Al(C2H5)2Cl or TiCl4 / Al(C2H2)2Cl as a catalyst.

[0006] Optionally, in one embodiment of the present invention, in step S1, ultra-high molecular weight polyethylene is prepared by using saturated hydrocarbons obtained by distillation at 60° C.-120° C. as a dispersion medium.

[0007] Optionally, in one embodiment of the present invention, the raw materials in step S1 further include a plasticizer.

[0008] Optionally, in one embodiment of the present invention, the preset formula ratio of step S2 is specifically: the mass ratio of each component is ultra-high molecular weight polyethylene 85%-90%, pigment 2%-3%, heat stabilizer 1%-2%, antioxidant 2%-3%, light stabilizer 5%-7%.

[0009] Optionally, in one embodiment of the present invention, the extruder in step S3 is set to three temperature zones, specifically: zone one temperature 140°C-160°C, zone two temperature 160°C-180°C, zone three temperature 180°C-200°C.

[0010] Optionally, in one embodiment of the present invention, the extruder is any one of a plunger extruder or a twin-screw extruder.

[0011] Beneficial effects of the present invention The manufacturing process of a polymer plastic product of the present invention is prepared with ultra-high molecular weight polyethylene as the main raw material, and the processing difficulty is relatively lower. The raw materials are also added with a variety of additives, so that the new material can be further improved in multiple properties such as wear resistance, weather resistance, and mechanical properties. The new material can be applied to a variety of high-end fields and has broad market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0013] Figure 1 This is a structural diagram of a manufacturing process of a polymer plastic product according to Example 1 of the present invention; Reference numerals: upper film layer 1 , middle film layer 2 , lower film layer 3 , release layer 4 . DETAILED DESCRIPTION

[0014] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0015] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments. Example

[0016] In order to make polymer plastics more suitable for application scenarios in high-end fields, a manufacturing process for polymer plastic products is designed. The specific plan is as follows: like Figure 1 As shown, a manufacturing process of a polymer plastic product specifically includes the following steps: Step S1, preparing ultra-high molecular weight polyethylene as the main raw material, and the raw materials also include pigments, heat stabilizers, antioxidants and light stabilizers; The specific steps of preparing ultra-high molecular weight polyethylene in step S1 are as follows: Step S101, preparing ultra-high molecular weight polyethylene using β-TiCl3 / Al(C2H5)2Cl or TiCl4 / Al(C2H2)2Cl as a catalyst; The main catalyst (β-TiCl3 / Al(C2H5)2Cl or TiCl4 / Al(C2H5)2Cl) and the co-catalyst are mixed evenly in a certain proportion to form a catalyst solution or suspension. The co-catalyst can be triethylaluminum, and 0.5g of the co-catalyst is mixed with every 1g of the main catalyst.

[0017] Step S102, using saturated hydrocarbons obtained from the 60°C-120°C fraction as a dispersion medium; Such as hexane, heptane, etc. These solvents have high stability within this temperature range and can effectively disperse and dissolve the catalyst and ethylene monomer. To ensure the smooth progress of the polymerization reaction, the dispersion medium needs to be strictly dehydrated and deoxygenated to remove impurities such as moisture and oxygen. When using, slowly add the catalyst to the dispersion medium that has been preheated to the set temperature and ensure that it is evenly dispersed.

[0018] Step S103, polymerizing polyethylene at 75° C.-85° C. under normal pressure to obtain ultra-high molecular weight polyethylene.

[0019] Under nitrogen protection, ethylene gas is introduced into the polymerization kettle, and an appropriate stirring speed is maintained to ensure that the catalyst and ethylene monomer are fully mixed in the dispersion medium. After obtaining the ultra-high molecular weight polyethylene, it needs to be washed, dried and granulated.

[0020] Step S2, according to a preset formula ratio, the raw materials are screened for particle size and then dried to ensure the purity and uniformity of the raw materials, the dried raw materials are weighed, and then put into a mixing device for mixing; The preset formula ratio of step S2 is specifically as follows: the mass ratio of each component is ultra-high molecular weight polyethylene 85%-90%, pigment 2%-3%, heat stabilizer 1%-2%, antioxidant 2%-3%, light stabilizer 5%-7%.

[0021] In this embodiment, ultra-high molecular weight polyethylene is 90%, pigment is 2%, heat stabilizer is 1%, antioxidant is 2%, and light stabilizer is 5%. Among them, the pigment should be selected from pigments with good compatibility and good dispersibility with ultra-high molecular weight polyethylene, the heat stabilizer can be organic tin compounds and calcium zinc composite stabilizers, and the antioxidant can be selected from pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, which can effectively improve the antioxidant properties of ultra-high molecular weight polyethylene and extend the service life of the product. The light stabilizer can be a composite light stabilizer, such as: light stabilizer 944 and ultraviolet absorber Tinuvin 327 / 328, to improve the light aging resistance and color stability of the product. Step S3, after uniform mixing, the raw materials are uniformly put into an extruder, and melt-extruded into a mold for forming; In step S3, the extruder is set to three zones, specifically: zone 1 temperature 140°C-160°C, zone 2 temperature 160°C-180°C, zone 3 temperature 180°C-200°C.

[0022] The extruder is either a ram extruder or a twin-screw extruder.

[0023] In this embodiment, the extruder is preferably a twin-screw extruder.

[0024] Step S4, the molded plastic product is cooled by either air cooling or natural cooling.

[0025] For cooling method, natural cooling is preferred to ensure that the surface of the material will not be affected when the plastic product is formed. Relatively high production efficiency is required. Air cooling has less impact on the surface of the material, is less likely to cause water marks or deformation, and the equipment is relatively simpler.

[0026] The manufacturing process of this scheme can produce ultra-high molecular weight polyethylene products with an average molecular weight greater than 1 million, and has excellent performance in multiple properties. In addition, multiple additives are added during preparation to further improve material properties. The material has high purity, the obtained products are of good quality, and the processing difficulty is relatively smaller. Example

[0027] In this embodiment, the manufacturing process is basically the same as that of Embodiment 1, except that a plasticizer is further added to the raw materials, and the amount of the plasticizer added is 5%-20% of the ultra-high molecular weight polyethylene, which is used to improve the flexibility and impact resistance of the product. Example

[0028] In this embodiment, the manufacturing process is substantially the same as the process steps of Embodiment 1, except that, in step S1, ultra-high molecular weight polyethylene is prepared, and the preparation steps are as follows: Step 1, using titanium tetrachloride as a catalyst and alkyl aluminum compounds as an activator. The catalyst carrier is often calcined to a large pore size MgCl2 or MgCl(OH); Step 2 is carried out in a closed loop reaction tube, the outer side of the loop reaction tube is provided with a cold water jacket, and the inner side of the loop reaction tube is provided with a high-speed turbine agitator to complex the catalyst and mix it with the introduced ethylene and the density-adjusting comonomer. The reaction temperature is controlled at 80-90°C, the ethylene partial pressure is 1.0 MPa, and the reaction time is 2-3 hours. Step 3: The slurry generated in step 2 is centrifugally filtered, the filter cake is stripped with steam to remove the residual solvent, and then air-dried to finally obtain an ultra-high molecular weight polyethylene with an average molecular weight of 1.5 million to 6 million.

[0029] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Although the present invention has been disclosed as above in the form of preferred embodiments, it is not intended to limit the present invention. Any technical personnel in the field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A process for manufacturing a polymer plastic product, characterized in that: The specific steps include: Step S1, preparing ultra-high molecular weight polyethylene as the main raw material, and the raw materials also include pigments, heat stabilizers, antioxidants and light stabilizers; Step S2, according to a preset formula ratio, the raw materials are screened for particle size and then dried to ensure the purity and uniformity of the raw materials, the dried raw materials are weighed, and then put into a mixing device for mixing; Step S3, after uniform mixing, the raw materials are uniformly put into an extruder, and melt-extruded into a mold for forming; Step S4, the molded plastic product is cooled by either air cooling or natural cooling.

2. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: The step S1 is to prepare ultra-high molecular weight polyethylene using β-TiCl3 / Al(C2H5)2Cl or TiCl4 / Al(C2H2)2Cl as a catalyst.

3. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: In the step S1, ultra-high molecular weight polyethylene is prepared by using saturated hydrocarbon obtained by distillation at 60° C.-120° C. as a dispersion medium.

4. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: The raw materials in step S1 also include a plasticizer.

5. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: The preset formula ratio of step S2 is specifically as follows: the mass ratio of each component is 85%-90% of ultra-high molecular weight polyethylene, 2%-3% of pigment, 1%-2% of heat stabilizer, 2%-3% of antioxidant, and 5%-7% of light stabilizer.

6. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: In step S3, the extruder is set according to three temperature zones, specifically: the temperature of zone 1 is 140°C-160°C, the temperature of zone 2 is 160°C-180°C, and the temperature of zone 3 is 180°C-200°C.

7. The manufacturing process of a polymer plastic product according to claim 1, characterized in that: The extruder is any one of a plunger extruder or a twin-screw extruder.

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