A wear-resistant antistatic plastic and its preparation method and application in caster preparation

Abstract

The present invention belongs to the technical field of polymer materials, and specifically relates to a wear-resistant antistatic plastic, a preparation method thereof, and an application thereof in the preparation of casters. The preparation method comprises the following steps: reacting hydroxy silicone oil with isocyanate ethyl acrylate to obtain an acrylate-terminated polysiloxane macromolecular monomer solution, then adding styrene, a diluting organic solvent, and an initiator to react, spray drying, and obtaining a polysiloxane copolymer cross-linked polystyrene elastomer powder, and then mixing it with a reinforcing agent, white carbon black, an antistatic agent, and a silane coupling agent, and then granulating it to obtain a wear-resistant antistatic reinforcing masterbatch, and mixing the obtained reinforcing masterbatch with a PP resin, and extruding it into a mold to form, and obtaining a wear-resistant antistatic plastic. The present invention adopts a polysiloxane copolymer cross-linked polystyrene elastomer to blend and modify the PP resin, which can significantly improve the elasticity and toughness of the PP resin, so that it has the advantages of high strength, wear resistance, antistatic, and shock absorption and shock resistance when used in the preparation of casters.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a wear-resistant antistatic plastic and a preparation method thereof and application thereof in the preparation of casters. Background Art

[0002] Casters are an indispensable part of daily life and industrial production, and the material selection has an important impact on performance and application areas.

[0003] At present, the commonly used raw materials for caster manufacturing are PP (polypropylene), PVC (polyvinyl chloride), PA (polyamide), PU (polyurethane), polyester, rubber, etc. PP, PVC, PA have good hardness and wear resistance, but poor elasticity and shock absorption and vibration resistance, and loud noise; PU, polyester, rubber, etc. have good shock resistance and vibration absorption functions, but low rigidity and limited load-bearing capacity.

[0004] In addition, in modern industrial production, especially in electronic production, processing and flammable and explosive production sites, casters have high requirements for antistatic performance. The above problems can be solved by adding antistatic additives. For example, patent CN 101475719 B discloses a special material for antistatic casters, including the following components by weight: 100 parts of polypropylene, 22 to 28 parts of reinforcing agent, 3 to 7 parts of conductive agent, 0.3 to 0.5 parts of lubricant, 8 to 14 parts of elastomer, and 0.3 to 0.7 parts of hindered phenol antioxidant. The antistatic effect is improved by adding a conductive agent, and its toughness is improved by adding EPDM rubber and / or octene-ethylene elastomer. However, in order to increase strength and wear resistance, it is necessary to add a reinforcing agent with a high content of glass fiber, carbon fiber or boron fiber, which has an adverse effect on toughness, and the high content of carbon fiber or boron fiber has a high cost. Patent CN113801485A discloses an antistatic and highly wear-resistant caster material, which includes the following raw materials: 10-20wt% of styrene elastomer, 20-30wt% of white oil, 5-10wt% of maleic anhydride grafted polystyrene elastomer, 10-20wt% of powdered rubber, 5-15wt% of poly-α-methylstyrene resin, 10-20wt% of polypropylene, 10-20wt% of ultra-high molecular weight polyethylene, 5-10wt% of antistatic additive, 4-10wt% of wear-resistant agent, 0.5-2wt% of lubricant, and 0.5-1.5wt% of antioxidant. Although the caster material can achieve good antistatic, wear-resistant, and shock-resistant effects, the raw material components are of many types and have large differences in properties, and the process requirements for blending are relatively high. Summary of the invention

[0005] In view of the shortcomings and deficiencies of the above prior art, the primary purpose of the present invention is to provide a method for preparing a wear-resistant and antistatic plastic.

[0006] Another object of the present invention is to provide a wear-resistant and antistatic plastic prepared by the above method.

[0007] Another object of the present invention is to provide application of the above-mentioned wear-resistant and antistatic plastic in the preparation of casters.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A method for preparing a wear-resistant and antistatic plastic comprises the following steps:

[0010] (1) adding hydroxy silicone oil and ethyl isocyanate acrylate in a molar ratio of 1:1.6-2 to an organic solvent and mixing them evenly, heating to 50-80° C. under N2 protection to react, and obtaining an acrylate-terminated polysiloxane macromonomer solution;

[0011] (2) adding styrene, a diluent organic solvent and an initiator to the acrylate-terminated polysiloxane macromolecular monomer solution of step (1), and reacting at 70 to 90° C. under N2 protection, and spray drying after the reaction to obtain a polysiloxane copolymer cross-linked polystyrene elastomer powder;

[0012] (3) mixing the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) with reinforcing agent white carbon black, an antistatic agent and a silane coupling agent, and then granulating them to obtain a wear-resistant and antistatic reinforcing masterbatch;

[0013] (4) The wear-resistant and antistatic reinforcing masterbatch obtained in step (3) is evenly mixed with the PP resin, and the mixture is extruded into a mold to obtain a wear-resistant and antistatic plastic.

[0014] Furthermore, the molecular formula of the hydroxy silicone oil in step (1) is HO(CH3)2SiO[Si(CH3)2O] n Si(CH3)2OH, its average molecular weight is 500~5000g / mol.

[0015] Furthermore, the organic solvent in step (1) and the dilution organic solvent in step (2) are at least one of carbon tetrachloride, benzene and toluene; more preferably toluene.

[0016] Furthermore, the reaction time in step (1) is 1 to 4 hours.

[0017] Furthermore, the amount of styrene added in step (2) is 3 to 6 times the total mass of hydroxy silicone oil and ethyl isocyanate acrylate.

[0018] Furthermore, the initiator in step (2) is azobisisobutyronitrile or benzoyl peroxide; the amount of the initiator added is 0.05% to 2% of the mass of styrene.

[0019] Furthermore, the insulation reaction time in step (2) is 4 to 10 hours.

[0020] Furthermore, the antistatic agent in step (3) is selected from at least one of conductive metal powder, alkyl quaternary ammonium salt, alkyl phosphate, and alkyl sulfonate.

[0021] Furthermore, the silane coupling agent in step (3) is selected from at least one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane and ethyltriethoxysilane.

[0022] Furthermore, in step (3), the amount of the reinforcing agent white carbon black added is 5% to 30% of the mass of the polysiloxane cross-linked polystyrene elastomer powder; the amount of the antistatic agent added is 2% to 10% of the mass of the polysiloxane cross-linked polystyrene elastomer powder; and the amount of the silane coupling agent added is 1% to 5% of the mass of the polysiloxane cross-linked polystyrene elastomer powder.

[0023] Furthermore, the mass ratio of the wear-resistant and antistatic reinforcing masterbatch to the PP resin mixed in step (4) is 5 to 30:100.

[0024] The synthesis of the acrylate-terminated polysiloxane macromonomer in the above preparation method involves the following reaction formula:

[0025]

[0026] By copolymerizing and cross-linking styrene with the above-mentioned macromonomers, on the one hand, the toughness of polystyrene is improved by introducing flexible polysiloxane chains; on the other hand, the resulting polysiloxane copolymerized cross-linked polystyrene elastomer can significantly improve its compatibility with PP resin after being mixed with reinforcing agent white carbon black and silane coupling agent. Through the above-mentioned effects, the strength, wear resistance and toughness of the resulting modified PP plastic are simultaneously improved.

[0027] A wear-resistant and antistatic plastic is prepared by the method.

[0028] Application of the above-mentioned wear-resistant and antistatic plastic in the preparation of casters.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The present invention uses polysiloxane copolymer cross-linked polystyrene elastomer to blend and modify PP resin, which can significantly improve the elasticity and toughness of PP resin, so that it has the advantages of high strength, wear resistance, antistatic and shock absorption when used in caster preparation.

[0031] (2) The present invention prepares wear-resistant and antistatic reinforcing masterbatch by mixing polysiloxane copolymer cross-linked polystyrene elastomer powder with reinforcing agent white carbon black, antistatic agent and silane coupling agent in advance, and then mixes with PP resin, which can significantly improve the blending effect. Through the joint action of the above components, the strength and wear resistance of the obtained plastic are significantly improved.

[0032] (3) The present invention uses acrylate-terminated polysiloxane macromolecular monomers to copolymerize and crosslink styrene, which can improve its toughness and enhance its blending compatibility with PP resin, and ultimately achieve the effect of improving the strength, wear resistance and toughness of the modified PP plastic. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0034] Example 1

[0035] A method for preparing a wear-resistant and antistatic plastic comprises the following steps:

[0036] (1) Hydroxyl silicone oil with an average molecular weight of 500 g / mol and ethyl isocyanate acrylate were added to a toluene solvent at a molar ratio of 1:1.6 and mixed evenly. The mixture was heated to about 70° C. under N2 protection and reacted for 1.5 h. The isocyanate group reaction was detected to be complete, thereby obtaining an acrylate-terminated polysiloxane macromolecular monomer solution.

[0037] (2) Add styrene, diluted toluene solvent and initiator azobisisobutyronitrile to the acrylate-terminated polysiloxane macromolecular monomer solution of step (1), wherein the amount of styrene added is 3 times the total mass of hydroxy silicone oil and isocyanate ethyl acrylate; the amount of diluted toluene solvent added is such that the polymerization monomer concentration is 28wt.%, and the amount of initiator azobisisobutyronitrile added is 0.8% of the mass of styrene, and the reaction is carried out at 80°C under N2 protection for 4 hours. After the reaction is completed, the reaction solution is pumped into a vacuum spray dryer for spray drying and powdering to obtain polysiloxane copolymer cross-linked polystyrene elastomer powder.

[0038] (3) Add the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) and the reinforcing agent white carbon black, the antistatic agent conductive aluminum powder and the silane coupling agent ethyltrimethoxysilane in a mass ratio of 100:20:5:3 into a mixer, mix evenly at 150-200° C., and then granulate to obtain a wear-resistant and antistatic reinforcing masterbatch.

[0039] (4) adding the wear-resistant and antistatic reinforcing masterbatch obtained in step (3) and PP resin in a mass ratio of 20:100 into a mixer, kneading at 150-200° C. evenly, and extruding into a mold to form a wear-resistant and antistatic plastic.

[0040] Example 2

[0041] A method for preparing a wear-resistant and antistatic plastic comprises the following steps:

[0042] (1) Hydroxyl silicone oil with an average molecular weight of 2200 g / mol and ethyl isocyanate acrylate were added to a toluene solvent at a molar ratio of 1:1.8 and mixed evenly. The mixture was heated to about 70° C. under N2 protection and reacted for 2 h. The isocyanate group reaction was detected to be complete, thereby obtaining an acrylate-terminated polysiloxane macromolecular monomer solution.

[0043] (2) Add styrene, diluted toluene solvent and initiator azobisisobutyronitrile to the acrylate-terminated polysiloxane macromolecular monomer solution of step (1), wherein the amount of styrene added is 5 times the total mass of hydroxy silicone oil and isocyanate ethyl acrylate; the amount of diluted toluene solvent added is such that the polymerization monomer concentration is 28wt.%, and the amount of initiator azobisisobutyronitrile added is 0.5% of the mass of styrene, and the reaction is carried out at 80°C under N2 protection for 4 hours. After the reaction is completed, the reaction solution is pumped into a vacuum spray dryer for spray drying and powdering to obtain polysiloxane copolymer cross-linked polystyrene elastomer powder.

[0044] (3) Add the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) and the reinforcing agent white carbon black, the antistatic agent conductive aluminum powder and the silane coupling agent ethyltrimethoxysilane in a mass ratio of 100:20:5:3 into a mixer, mix evenly at 150-200° C., and then granulate to obtain a wear-resistant and antistatic reinforcing masterbatch.

[0045] (4) adding the wear-resistant and antistatic reinforcing masterbatch obtained in step (3) and PP resin in a mass ratio of 20:100 into a mixer, kneading at 150-200° C. evenly, and extruding into a mold to form a wear-resistant and antistatic plastic.

[0046] Example 3

[0047] A method for preparing a wear-resistant and antistatic plastic comprises the following steps:

[0048] (1) Hydroxyl silicone oil with an average molecular weight of 4500 g / mol and ethyl isocyanate acrylate are added to a toluene solvent in a molar ratio of 1:2 and mixed evenly. The mixture is heated to about 70° C. under N2 protection and reacted for 2 h. The isocyanate group reaction is detected to be complete, thereby obtaining an acrylate-terminated polysiloxane macromolecular monomer solution.

[0049] (2) Add styrene, diluted toluene solvent and initiator benzoyl peroxide to the acrylate-terminated polysiloxane macromolecular monomer solution of step (1), wherein the amount of styrene added is 6 times the total mass of hydroxy silicone oil and isocyanate ethyl acrylate; the amount of diluted toluene solvent added is such that the polymerization monomer concentration is 28wt.%, and the amount of initiator benzoyl peroxide added is 1.0% of the mass of styrene, and the reaction is carried out at 85°C under N2 protection for 6 hours. After the reaction is completed, the reaction solution is pumped into a vacuum spray dryer for spray drying and powdering to obtain polysiloxane copolymer cross-linked polystyrene elastomer powder.

[0050] (3) Add the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) and the reinforcing agent white carbon black, the antistatic agent conductive aluminum powder and the silane coupling agent ethyltrimethoxysilane in a mass ratio of 100:20:5:3 into a mixer, mix evenly at 150-200° C., and then granulate to obtain a wear-resistant and antistatic reinforcing masterbatch.

[0051] (4) adding the wear-resistant and antistatic reinforcing masterbatch obtained in step (3) and PP resin in a mass ratio of 20:100 into a mixer, kneading at 150-200° C. evenly, and extruding into a mold to form a wear-resistant and antistatic plastic.

[0052] Comparative Example 1

[0053] A method for preparing a wear-resistant and antistatic plastic. Compared with Example 1, the amount of styrene added in step (2) is reduced to twice the total mass of hydroxy silicone oil and isocyanate ethyl acrylate, and the rest are the same.

[0054] Comparative Example 2

[0055] A method for preparing a wear-resistant and antistatic plastic. Compared with Example 1, the amount of styrene added in step (2) is increased to 7 times the total mass of hydroxy silicone oil and isocyanate ethyl acrylate, and the rest is the same.

[0056] Comparative Example 3

[0057] A method for preparing a wear-resistant and antistatic plastic comprises the following steps:

[0058] Steps (1) to (2) are the same as those in Example 1.

[0059] (3) Add the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) and the reinforcing agent white carbon black, the antistatic agent conductive aluminum powder, the silane coupling agent ethyltrimethoxysilane and the PP resin in a mass ratio of 15.63:3.12:0.78:0.47:100 into a mixer, mix evenly at 150-200° C., extrude into a mold for molding, and obtain a wear-resistant and antistatic plastic.

[0060] Comparative Example 4

[0061] A method for preparing a wear-resistant and antistatic plastic, compared with Example 1, uses styrene-butadiene-styrene thermoplastic elastomer (SBS) to replace polysiloxane copolymer cross-linked polystyrene elastomer, and the specific preparation steps are as follows:

[0062] (1) Styrene-butadiene-styrene thermoplastic elastomer, reinforcing agent white carbon black, antistatic agent conductive aluminum powder and silane coupling agent ethyltrimethoxysilane are added into a mixer in a mass ratio of 100:20:5:3, kneaded at 150-200° C., and pelletized to obtain a wear-resistant and antistatic reinforcing masterbatch.

[0063] (2) adding the wear-resistant and antistatic reinforcing masterbatch obtained in step (1) and PP resin in a mass ratio of 20:100 into a mixer, kneading at 150-200° C. evenly, and extruding into a mold to form a wear-resistant and antistatic plastic.

[0064] The hardness (Shore durometer method), tensile strength (GB / T1040-2006), elongation at break (GB / T 1040-2006), impact strength (GB / T1043-2008) and wear resistance (reference ASTM D3702-2019, measured by mass loss wear rate) of the wear-resistant and antistatic plastics obtained in the above embodiments and comparative examples were tested, and the results are shown in Table 1 below.

[0065] Table 1

[0066]

[0067] It can be seen from the comparison results of comparative example 1 and embodiment 1 that the low proportion of styrene segments in the polysiloxane copolymer cross-linked polystyrene elastomer will lead to a decrease in hardness, strength, toughness and an increase in wear rate. The reason may be that the low amount of styrene added will lead to a decrease in thermoplasticity of the polysiloxane copolymer cross-linked polystyrene elastomer, and its mixing effect with the reinforcing agent white carbon black, antistatic agent and silane coupling agent will deteriorate, and ultimately lead to a deterioration in the reinforcing effect. It can be seen from the comparison results of comparative example 2 and embodiment 1 that although the high proportion of styrene segments in the polysiloxane copolymer cross-linked polystyrene elastomer can improve the hardness of the plastic, the strength and toughness are significantly reduced, and the wear rate has a certain degree of increase. The reason may be that the low proportion of polysiloxane segments leads to an insignificant effect of improving toughness, and the low proportion of polysiloxane segments leads to a poor blending effect with the reinforcing agent white carbon black and silane coupling agent, which further leads to a deterioration in the blending effect of the reinforcing masterbatch and the PP resin, and ultimately leads to a deterioration in the strengthening and toughening effect. From the comparison results of comparative example 3 and example 1, it can be seen that the modification effect of directly mixing polysiloxane copolymer cross-linked polystyrene elastomer powder with PP resin is poor. The present invention prepares wear-resistant and antistatic reinforcing masterbatch by mixing polysiloxane copolymer cross-linked polystyrene elastomer powder with reinforcing agent white carbon black, antistatic agent and silane coupling agent in advance, and utilizes the good compatibility of reinforcing agent white carbon black and silane coupling agent with polysiloxane copolymer cross-linked polystyrene elastomer to improve the mixing effect of polysiloxane copolymer cross-linked polystyrene elastomer and PP resin, thereby improving the modification effect. From the comparison results of comparative example 4 and example 1, it can be seen that the PP plastic toughened with conventional SBS is inferior to the present invention in terms of strength, toughness and wear resistance.

[0068] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principles of the present invention shall be equivalent replacement methods and shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a wear-resistant and antistatic plastic, characterized in that: The method comprises the following preparation steps: (1) Add hydroxy silicone oil and ethyl isocyanate acrylate in a molar ratio of 1:1.6-2 into an organic solvent and mix evenly, and heat to 50-80°C under N2 protection to react to obtain an acrylate-terminated polysiloxane macromolecular monomer solution; (2) adding styrene, a diluent organic solvent and an initiator to the acrylate-terminated polysiloxane macromolecular monomer solution of step (1), and reacting at 70-90° C. under N2 protection, and spray drying after the reaction is completed to obtain a polysiloxane copolymer cross-linked polystyrene elastomer powder; (3) the polysiloxane copolymer cross-linked polystyrene elastomer powder obtained in step (2) is mixed evenly with reinforcing agent white carbon black, antistatic agent and silane coupling agent, and then granulated to obtain a wear-resistant and antistatic reinforcing masterbatch; (4) uniformly mixing the wear-resistant and antistatic reinforcing masterbatch obtained in step (3) with the PP resin, and extruding the mixture into a mold to obtain a wear-resistant and antistatic plastic; The molecular formula of the hydroxy silicone oil in step (1) is HO(CH3)2SiO[Si(CH3)2O] n Si(CH3)2OH, with an average molecular weight of 500~5000g / mol; The amount of styrene added in step (2) is 3 to 6 times the total mass of hydroxy silicone oil and ethyl isocyanate acrylate; In step (3), the amount of the reinforcing agent white carbon black added is 5% to 30% of the mass of the polysiloxane cross-linked polystyrene elastomer powder; the amount of the antistatic agent added is 2% to 10% of the mass of the polysiloxane cross-linked polystyrene elastomer powder; the amount of the silane coupling agent added is 1% to 5% of the mass of the polysiloxane cross-linked polystyrene elastomer powder; The mass ratio of the wear-resistant and antistatic reinforcing masterbatch to the PP resin in step (4) is 5-30:

100.

2. The method for preparing a wear-resistant and antistatic plastic according to claim 1, characterized in that: The organic solvent in step (1) and the dilution organic solvent in step (2) are at least one of carbon tetrachloride, benzene and toluene.

3. The method for preparing a wear-resistant and antistatic plastic according to claim 1, characterized in that: The initiator in step (2) is azobisisobutyronitrile or benzoyl peroxide; the amount of the initiator added is 0.05% to 2% of the mass of styrene.

4. The method for preparing a wear-resistant and antistatic plastic according to claim 1, characterized in that: The antistatic agent in step (3) is selected from at least one of conductive metal powder, alkyl quaternary ammonium salt, alkyl phosphate, and alkyl sulfonate; the silane coupling agent is selected from at least one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, and ethyltriethoxysilane.

5. A wear-resistant and antistatic plastic, characterized in that: It is prepared by the method according to any one of claims 1 to 4.

6. Use of the wear-resistant and antistatic plastic according to claim 5 in the preparation of casters.

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