Long-acting environment-friendly flame-retardant anti-static rubber pad and preparation method thereof

Abstract

The invention discloses a long-acting environment-friendly flame-retardant anti-static rubber pad and a preparation method thereof, and relates to the technical field of rubber pads. The long-acting environment-friendly flame-retardant anti-static rubber pad prepared by the application comprises the static conductive layer at the bottom layer and the static dissipation layer attached to one surface of the static conductive layer. The static dissipation layer comprises modified nitrile rubber, acrylate resin and a first auxiliary agent; and the static conductive layer comprises modified nitrile rubber, butadiene styrene rubber, polyurethane resin and a second auxiliary agent. Wherein the modified nitrile rubber is obtained by reacting a Grignard reagent RMgBr with cyano groups in nitrile rubber, converting the cyano groups into carbonyl groups, and introducing a phosphorus-containing organic compound into the nitrile rubber by utilizing aldol condensation. The rubber pad prepared from the modified nitrile rubber is excellent in anti-static performance, has flame retardance, is long-acting and environment-friendly, and has a wide application prospect.

Description

Technical Field

[0001] The present application relates to the technical field of rubber pads, and in particular to a long-lasting, environmentally friendly, flame-retardant and antistatic rubber pad and a preparation method thereof. Background Art

[0002] With the rapid development of the electronics industry, static electricity problems have become increasingly prominent, posing a serious threat to the normal operation of electronic equipment and personnel safety. As an important tool for eliminating static electricity, the market demand for antistatic rubber mats continues to grow. However, existing antistatic rubber mats have certain limitations in terms of service life, environmental performance, and production process. For example, some rubber mats are prone to aging and cracking during use, resulting in a decrease in antistatic performance; at the same time, more toxic and harmful substances may be used in traditional production processes, causing potential harm to the environment and human health. Therefore, it is of great significance to develop a long-lasting, environmentally friendly, flame-retardant, antistatic rubber mat and a preparation method thereof.

[0003] The Chinese patent with publication number CN 112358665 A discloses an antistatic rubber composition, an antistatic rubber floor and a preparation method thereof, wherein the antistatic rubber composition comprises: 100 parts by weight of nitrile rubber, 8 to 15 parts by weight of ethylene-acrylate-glycidyl methacrylate copolymer, 0.5 to 3 parts by weight of aluminum-doped zinc oxide composite material coated with polypyridine, 3 to 6 parts by weight of vulcanization accelerator, 10 to 20 parts by weight of flame retardant and 20 to 30 parts by weight of reinforcing filler; wherein the aluminum-doped zinc oxide composite material coated with polypyridine comprises aluminum-doped zinc oxide with a particle size of 40 to 150 nm and polypyrrole coated on the surface thereof, wherein the polypyrrole accounts for 5 to 20% of the weight of the aluminum-doped zinc oxide, and the aluminum doping amount in the aluminum-doped zinc oxide is 1 to 3% by weight based on aluminum oxide. The antistatic rubber composition and the antistatic rubber floor have improved antistatic performance, and the color is not limited to black.

[0004] However, the resistivity of the antistatic rubber composition and antistatic rubber floor prepared by this solution is still relatively low, and the improvement of its flame retardant performance is mainly due to the physical doping of flame retardants rather than the introduction of flame retardant components through chemical reactions. In addition, this solution does not specifically reflect the performance of the antistatic rubber floor prepared in terms of aging resistance, corrosion resistance and other aspects related to long-term use, and there is still room for improvement. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present application provides a long-lasting and environmentally friendly flame-retardant antistatic rubber mat and a preparation method thereof, wherein the Grignard reagent RMgBr is used to react with the cyanide group in the nitrile rubber to convert the cyanide group into a carbonyl group, and then the phosphorus-containing organic compound is introduced into the nitrile rubber by aldol condensation to obtain a modified nitrile rubber; and then the modified nitrile rubber is used as the main raw material to prepare the conductive layer rubber material and the static dissipative layer rubber material, thereby obtaining a long-lasting and environmentally friendly flame-retardant antistatic rubber mat. The long-lasting and environmentally friendly flame-retardant antistatic rubber mat has excellent antistatic performance, is flame-retardant, and is long-lasting and environmentally friendly, and has broad application prospects.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions: In the first aspect, the present application provides a long-lasting, environmentally friendly, flame-retardant, antistatic rubber pad, comprising a bottom electrostatic conductive layer and an electrostatic dissipative layer attached to one side of the electrostatic conductive layer; the electrostatic dissipative layer comprises modified nitrile rubber, an acrylate resin and a first additive; the electrostatic conductive layer comprises modified nitrile rubber, styrene-butadiene rubber, a polyurethane resin and a second additive; the modified nitrile rubber is obtained by using a Grignard reagent RMgBr to react with a cyanide group in the nitrile rubber to convert the cyanide group into a carbonyl group, and then using aldol condensation to introduce a phosphorus-containing organic compound into the nitrile rubber; wherein R in the Grignard reagent comprises any one of a methyl group, an ethyl group, an n-propyl group, and an n-butyl group.

[0007] In a second aspect, the present application provides a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad, comprising: Add nitrile rubber and solvent into the reactor, stir at 20-30°C under nitrogen protection for 1-2 hours; Keep stirring at the same temperature under nitrogen, add the Grignard reagent dropwise into the reactor within 1 hour, and continue stirring for 10-12 hours; Continue to add the phosphorus-containing organic compound to the reactor and adjust the pH of the mixture in the reactor to 1-2; Add 4A molecular sieve powder into the reaction kettle, and continue stirring at 20-30° C. for 0.5-1 hour under nitrogen protection to obtain the modified nitrile rubber; The modified nitrile rubber and the acrylic resin are kneaded at 60-70°C for 10-20 minutes, and then paraffin oil, talcum powder, antioxidant and the first accelerator are added, and the kneading is continued for 10-20 minutes and then calendered to obtain a static dissipative layer rubber material; The modified nitrile rubber, styrene-butadiene rubber and polyurethane resin are mixed at 60-70°C for 10-20 minutes, and then conductive carbon black, carbon nanotubes, plasticizer and second accelerator are added, and the mixing is continued for 10-20 minutes and then calendered to obtain a conductive static layer rubber material; Use the conductive layer adhesive as the bottom layer, apply glue on the side of the conductive layer for lamination, and then laminate the static dissipative layer adhesive on the conductive layer, and perform hot pressing at 130-150℃; The pressed rubber pad is placed in a vulcanizer and vulcanized under the conditions of 6-12 MPa and 150-180° C. to obtain the long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0008] Beneficial technical effects: The present application adopts a unique synthesis method, uses the Grignard reagent RMgBr to react with the cyanide group in the nitrile rubber to convert the cyanide group into a carbonyl group, and then uses the aldol condensation to introduce the phosphorus-containing organic compound into the nitrile rubber to form a phosphorus-containing group to obtain a modified nitrile rubber; then the modified nitrile rubber is used as the main raw material to prepare the electrostatic conductive layer rubber material and the electrostatic dissipative layer rubber material, thereby obtaining a long-lasting and environmentally friendly flame-retardant antistatic rubber mat.

[0009] The phosphorus-containing group introduced by chemical reaction in the modified acrylonitrile-butadiene rubber of the present application will not have the phenomenon of maldistribution directly added in polymers similar to phosphorus-containing compounds, and the problem of physical changes such as volatilization, dissolution or migration is easy to occur during processing or use. And the phosphorus-containing group introduced by chemical reaction generates phosphorus oxides with free radical reaction at high temperature, and these phosphorus oxides can form a protective layer on the rubber pad surface, prevent heat transfer and oxygen diffusion, and significantly improve the heat resistance and flame retardancy of antistatic rubber pad. Meanwhile, the addition of acrylate resin and polyurethane resin can promote the oil resistance and chemical corrosion resistance of antistatic rubber pad. The combination of the above points can significantly increase its flame retardancy and service life while maintaining the excellent antistatic performance of the rubber pad, and the overall process materials are environmentally friendly, with broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural diagram of a long-lasting, environmentally friendly, flame-retardant, antistatic rubber mat.

[0011] Figure 2 It is a schematic diagram of the chemical reaction for preparing modified nitrile rubber.

[0012] Figure 3 It is a schematic diagram of the process of preparing long-lasting and environmentally friendly flame-retardant antistatic rubber mats.

[0013] Figure 4 is the chemical structural formula of the modified nitrile rubber prepared in Example 1.

[0014] Reference numerals: 1. static dissipative layer; 2. static conductive layer. DETAILED DESCRIPTION

[0015] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application is further described in detail below in conjunction with the embodiments. However, this should not be understood as the scope of the present application being limited to the following examples. Without departing from the above-mentioned method ideas of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0016] In this application, the terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit the application.

[0017] As used in this application, the singular forms "for", "or", "a", "any", "any one" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0018] In addition, if the terms “first” or “second” appear, they are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0019] In the first aspect, the present application provides a long-lasting, environmentally friendly, flame-retardant, antistatic rubber pad, comprising a bottom electrostatic conductive layer 2 and a static dissipative layer 1 adhered to one side of the static conductive layer 2; the static dissipative layer 1 comprises modified nitrile rubber, an acrylate resin and a first additive; the static conductive layer 2 comprises modified nitrile rubber, a polyurethane resin and a second additive; the modified nitrile rubber is obtained by using a Grignard reagent RMgBr to react with a cyanide group in the nitrile rubber to convert the cyanide group into a carbonyl group, and then using aldol condensation to introduce a phosphorus-containing organic compound into the nitrile rubber.

[0020] In a possible implementation, R in the Grignard reagent includes any one of methyl, ethyl, n-propyl, and n-butyl.

[0021] In a possible implementation, the structure of the phosphorus-containing organic compound is: .

[0022] In a possible implementation, in the static dissipative layer 1, the first auxiliary agent includes an antistatic agent, paraffin oil, talcum powder, an antioxidant and a first accelerator; the mass ratio of the modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talcum powder, antioxidant and first accelerator is (25~50): (10~30): (2~10): (10~25): (4-9): (1~3): (3~10).

[0023] In a possible implementation, in the electrostatically conductive layer 2, the second auxiliary agent includes conductive carbon black, carbon nanotubes, a plasticizer and a second accelerator; the mass ratio of the modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, plasticizer and second accelerator is (20~40): (10~40): (15~30): (10~20): (5~10): (5~15): (3~10).

[0024] In a possible implementation, the structure of the modified nitrile rubber includes: ; Wherein R includes any one of methyl, ethyl, n-propyl and n-butyl; x is an integer in the range of 60 to 150; and y is an integer in the range of 50 to 80.

[0025] In a possible implementation, the antioxidant includes one or more of diphenylamine, 2,6-di-tert-butyl-p-cresol, and triphenylphosphine.

[0026] In a possible implementation, the first accelerator includes one or more of N-cyclohexyl-2-benzothiazole sulfenamide, N-tert-butyl-2-benzothiazole sulfenamide, and 2-mercaptobenzothiazole.

[0027] In a possible implementation, the plasticizer includes one or more of dioctyl phthalate, dioctyl adipate, and diisooctyl sebacate.

[0028] In a possible implementation, the second accelerator includes one or more of tetramethylthiuram disulfide, zinc diethyldithiocarbamate, and zinc dimethyldithiocarbamate.

[0029] In a second aspect, the present application provides a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad, such as Figure 3 As shown, including: Add nitrile rubber and solvent into the reactor, stir at 20-30°C under nitrogen protection for 1-2 hours; Keep stirring at the same temperature under nitrogen, add the Grignard reagent dropwise into the reactor within 1 hour, and continue stirring for 10-12 hours; Continue to add the phosphorus-containing organic compound to the reactor and adjust the pH of the mixture in the reactor to 1-2; Add 4A molecular sieve powder into the reaction kettle, and continue stirring at 20-30° C. for 0.5-1 hour under nitrogen protection to obtain the modified nitrile rubber; The modified nitrile rubber and the acrylic resin are kneaded at 60-70°C for 10-20 minutes, and then paraffin oil, talcum powder, an antioxidant, and a first accelerator are added, and the kneading is continued for 10-20 minutes, and then calendered to obtain a static dissipative layer 1 rubber material; The modified nitrile rubber, styrene-butadiene rubber and polyurethane resin are mixed at 60-70°C for 10-20 minutes, and then conductive carbon black, carbon nanotubes, plasticizer and second accelerator are added, and the mixing is continued for 10-20 minutes and then calendered to obtain the conductive layer 2 rubber material; Use the adhesive material of the static conductive layer 2 as the bottom layer, apply glue on the side of the static conductive layer 2 for lamination, and then laminate the adhesive material of the static dissipative layer 1 on the static conductive layer 2, and perform hot pressing at 130-150°C; The pressed rubber pad is placed in a vulcanizer and vulcanized under the conditions of 6-12 MPa and 150-180° C. to obtain the long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0030] In a possible implementation, the solvent includes one or more of dichloromethane, toluene, and ethyl acetate.

[0031] In a possible implementation, the mass ratio of the nitrile rubber, the solvent, the Grignard reagent, the phosphorus-containing organic compound, and the 4A molecular sieve powder is: (30-50): (20-40): (10-15): (5-10): (5-15).

[0032] In a possible implementation, the glue includes one or both of nitrile latex and polyurethane adhesive.

[0033] The following will describe in detail a long-lasting, environmentally friendly, flame-retardant, antistatic rubber pad and a preparation method thereof provided by the present application in combination with different embodiments.

[0034] Embodiment 1:

[0035] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and dichloromethane into the reactor and stir at 25°C under nitrogen protection for 1.5 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 11 hours; 3. Then add the phosphorus-containing organic compound to the reactor and adjust the pH to 1.5; 4. Then add 4A molecular sieve powder to the reactor and continue stirring at 25°C for 0.5 hours to obtain modified nitrile rubber, the chemical structure of which is as follows: Figure 4 As shown; In steps 1 to 4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH3MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 30:40:15:7:8; 5. After that, the modified nitrile rubber and the acrylic resin were kneaded at 65° C. for 15 minutes, and then an antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide were added, and the kneading was continued for 15 minutes, and then calendering was performed to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide is 40:25:5:15:5:2:8; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 65° C. for 15 minutes, and then conductive carbon black, carbon nanotubes, dioctyl phthalate and tetramethylthiuram disulfide were added. The mixture was further mixed for 15 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl phthalate, and tetramethylthiuram disulfide is 25:20:15:15:8:10:7; 7. Then, the conductive layer 2 rubber material is used as the bottom layer, and nitrile latex is applied on the side for bonding, and then the static dissipative layer 1 rubber material is bonded thereon, and hot pressing is performed at 140°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 9MPa and 165℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0036] Embodiment 2:

[0037] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and toluene into the reactor and stir at 28°C under nitrogen protection for 2 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 1; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 28°C for 1 hour to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, toluene, Grignard reagent CH3CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 40:30:12:8:10; 5. After that, the modified nitrile rubber and the acrylic resin were kneaded at 70° C. for 18 minutes, and then an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfonamide were added, and the kneading was continued for 18 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfenamide is 36:20:10:18:4:2:10; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 70° C. for 18 minutes, and then conductive carbon black, carbon nanotubes, dioctyl adipate and zinc diethyldithiocarbamate were added. The mixture was further mixed for 18 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate is 20:20:20:18:7:7:8; 7. Then, the conductive layer 2 adhesive is used as the bottom layer, and a polyurethane adhesive is applied to the side for bonding, and then the static dissipative layer 1 adhesive is bonded thereon, and hot pressing is performed at 135°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 7MPa and 170℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0038] Embodiment 3:

[0039] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and ethyl acetate into the reactor and stir at 30°C under nitrogen protection for 1 hour; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having the structure of CH3CH2CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 12 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 2; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 30°C for 0.5 hours to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, ethyl acetate, Grignard reagent CH3CH2CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 45:25:12:8:10; 5. After that, the modified nitrile rubber and the acrylic resin are kneaded at 60° C. for 20 minutes, and then an antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and 2-mercaptobenzothiazole are added, and the kneading is continued for 20 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, triphenylphosphine and 2-mercaptobenzothiazole is 32:20:10:18:8:2:10; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 60° C. for 20 minutes, and then conductive carbon black, carbon nanotubes, diisooctyl sebacate and zinc dimethyldithiocarbamate were added. The mixture was further mixed for 20 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, diisooctyl sebacate, and zinc dimethyldithiocarbamate is 20:20:25:15:5:10:5; 7. Then, the conductive layer 2 rubber material is used as the bottom layer, and nitrile latex is applied on the side for bonding, and then the static dissipative layer 1 rubber material is bonded thereon, and hot pressing is performed at 145°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 12MPa and 155℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0040] Embodiment 4:

[0041] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and dichloromethane into the reactor and stir at 24°C under nitrogen protection for 2 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3CH2CH2CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10.5 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 1; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 24°C for 1 hour to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH3CH2CH2CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 50:20:12:8:10.

[0042] 5. After that, the modified nitrile rubber and the acrylic resin were mixed at 67° C. for 16 minutes, and then an antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-tert-butyl-2-benzothiazole sulfonamide were added, and the mixture was further mixed for 16 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, diphenylamine, and N-tert-butyl-2-benzothiazole sulfenamide is 35:28:8:12:7:3:7; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 67° C. for 18 minutes, and then conductive carbon black, carbon nanotubes, dioctyl phthalate and zinc dimethyl dithiocarbamate were added. The mixture was further mixed for 18 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl phthalate, and zinc dimethyldithiocarbamate is 20:15:20:20:7:12:6; 7. Then, the conductive layer 2 adhesive is used as the bottom layer, and a polyurethane adhesive is applied to the side for bonding, and then the static dissipative layer 1 adhesive is bonded thereon, and hot pressing is performed at 150°C; 8. Finally, put the pressed rubber pad into a vulcanizer and vulcanize it at 10MPa and 150°C to obtain a long-lasting, environmentally friendly, flame-retardant and antistatic rubber pad.

[0043] Embodiment 5:

[0044] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and ethyl acetate into the reactor and stir at 25°C under nitrogen protection for 1.2 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10 hours; 3. Then add the phosphorus-containing organic compound to the reactor and adjust the pH to 1.2; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 25°C for 0.5 hours to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, ethyl acetate, Grignard reagent CH3CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 40:25:10:10:15.

[0045] 5. After that, the modified nitrile rubber and the acrylic resin were mixed at 62° C. for 15 minutes, and then an antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and N-cyclohexyl-2-benzothiazole sulfenamide were added, and the mixture was further mixed for 15 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, triphenylphosphine, and N-cyclohexyl-2-benzothiazole sulfenamide is 35:25:10:20:5:2:3; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 62° C. for 15 minutes, and then conductive carbon black, carbon nanotubes, diisooctyl sebacate and tetramethylthiuram disulfide were added. The mixture was further mixed for 15 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, diisooctyl sebacate, and tetramethylthiuram disulfide is 30:15:20:16:9:7:3; 7. Then, the conductive layer 2 rubber material is used as the bottom layer, and nitrile latex is applied on the side for bonding, and then the static dissipative layer 1 rubber material is bonded thereon, and hot pressing is performed at 145°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 6MPa and 180℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0046] Embodiment 6:

[0047] like Figure 3 As shown, a method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and toluene into the reactor and stir at 20°C under nitrogen protection for 1.5 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3CH2CH2CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 1; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 20°C for 1 hour to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, toluene, Grignard reagent CH3CH2CH2CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 45:20:15:10:10.

[0048] 5. After that, the modified nitrile rubber and the acrylic resin were kneaded at 70° C. for 10 minutes, and then an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfonamide were added, and the kneading was continued for 10 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfenamide is 30:30:9:12:9:3:7; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 70° C. for 10 minutes, and then conductive carbon black, carbon nanotubes, dioctyl adipate and zinc diethyldithiocarbamate were added. The mixture was further mixed for 10 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate is 35:15:15:13:7:9:6; 7. Then, the conductive layer 2 adhesive is used as the bottom layer, and a polyurethane adhesive is applied to the side for bonding, and then the static dissipative layer 1 adhesive is bonded thereon, and hot pressing is performed at 150°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 7MPa and 175℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0049] Comparative Example 1: A method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and dichloromethane into the reactor and stir at 25°C under nitrogen protection for 1.5 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 11 hours; 3. Then add ethylene glycol to the reactor and adjust the pH to 1.5; 4. Then add 4A molecular sieve powder to the reactor and continue stirring at 25°C for 0.5 hours to obtain modified nitrile rubber, the chemical structure of which is as follows: Figure 4 As shown; In steps 1 to 4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH3MgBr, ethylene glycol, and 4A molecular sieve powder is 30:40:15:7:8; 5. After that, the modified nitrile rubber and the acrylic resin were kneaded at 65° C. for 15 minutes, and then an antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide were added, and the kneading was continued for 15 minutes, and then calendering was performed to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide is 40:25:5:15:5:2:8; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 65° C. for 15 minutes, and then conductive carbon black, carbon nanotubes, dioctyl phthalate and tetramethylthiuram disulfide were added. The mixture was further mixed for 15 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl phthalate, and tetramethylthiuram disulfide is 25:20:15:15:8:10:7; 7. Then, the conductive layer 2 rubber material is used as the bottom layer, and nitrile latex is applied on the side for bonding, and then the static dissipative layer 1 rubber material is bonded thereon, and hot pressing is performed at 140°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 9MPa and 165℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0050] Comparative Example 2: A method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and ethyl acetate into the reactor and stir at 30°C under nitrogen protection for 1 hour; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having the structure of CH3CH2CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 12 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 2; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 30°C for 0.5 hours to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, ethyl acetate, Grignard reagent CH3CH2CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 45:25:12:8:10; 5. After that, the modified nitrile rubber was kneaded at 60° C. for 20 minutes, and then an antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and 2-mercaptobenzothiazole were added, and the mixture was kneaded for another 20 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, antistatic agent, paraffin oil, talc, triphenylphosphine and 2-mercaptobenzothiazole is 52:10:18:8:2:10; 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin were mixed at 60° C. for 20 minutes, and then conductive carbon black, carbon nanotubes, diisooctyl sebacate and zinc dimethyldithiocarbamate were added. The mixture was further mixed for 20 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, diisooctyl sebacate, and zinc dimethyldithiocarbamate is 20:20:25:15:5:10:5; 7. Then, the conductive layer 2 rubber material is used as the bottom layer, and nitrile latex is applied on the side for bonding, and then the static dissipative layer 1 rubber material is bonded thereon, and hot pressing is performed at 145°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 12MPa and 155℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0051] Comparative Example 3: A method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad comprises the following steps: 1. Add nitrile rubber and toluene into the reactor and stir at 20°C under nitrogen protection for 1.5 hours; 2. Then, the mixture was stirred under nitrogen at the same temperature, and a Grignard reagent having a structure of CH3CH2CH2CH2MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10 hours; 3. Then, add the phosphorus-containing organic compound to the reactor and adjust the pH to 1; 4. Then add 4A molecular sieve powder into the reactor and continue stirring at 20°C for 1 hour to obtain modified nitrile rubber; In steps 1 to 4, the mass ratio of nitrile rubber, toluene, Grignard reagent CH3CH2CH2CH2MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is 45:20:15:10:10.

[0052] 5. After that, the modified nitrile rubber and the acrylic resin were kneaded at 70° C. for 10 minutes, and then an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfonamide were added, and the kneading was continued for 10 minutes and then calendered to obtain a static dissipative layer 1 rubber material; The mass ratio of modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talc, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazolesulfenamide is 30:30:9:12:9:3:7; 6. At the same time, the modified nitrile rubber was kneaded at 70° C. for 10 minutes, and then conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate were added, and the mixture was further kneaded for 10 minutes and then calendered to obtain a conductive layer 2 rubber material; The mass ratio of modified nitrile rubber, styrene butadiene rubber, conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate is 35:30:13:7:9:6; 7. Then, the conductive layer 2 adhesive is used as the bottom layer, and a polyurethane adhesive is applied to the side for bonding, and then the static dissipative layer 1 adhesive is bonded thereon, and hot pressing is performed at 150°C; 8. Finally, put the pressed rubber pad into the vulcanizer and vulcanize it under the conditions of 7MPa and 175℃ to obtain a long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

[0053] With reference to GB / T 1690-2010, the liquid resistance performance of the long-lasting and environmentally friendly flame-retardant antistatic rubber pad prepared in the present application was tested by the liquid resistance test method, and the mass reduction ratio after immersion in mineral oil was calculated.

[0054] With reference to GB / T 3512-2014, the aging resistance of the long-lasting and environmentally friendly flame-retardant antistatic rubber mat prepared in the present application was tested by a hot air accelerated aging test, and the tensile strength retention rate after aging was calculated.

[0055] The above two points reflect the long-term durability of the long-lasting, environmentally friendly, flame-retardant and antistatic rubber mat prepared in this application.

[0056] With reference to GB / T 8624-2012, the flame retardancy test of the long-lasting and environmentally friendly flame retardant antistatic rubber mat prepared in the present application is carried out to reflect its flame retardant performance.

[0057] With reference to GB / T 11210-2014, the resistance test of the long-lasting and environmentally friendly flame-retardant antistatic rubber mat prepared in the present application is carried out to reflect its antistatic performance.

[0058] In addition, the long-lasting and environmentally friendly flame-retardant antistatic rubber pad prepared in this application was also compared with other competing products in related performance tests, as shown in Tables 2 and 3.

[0059] Table 1 Performance test results of the long-lasting and environmentally friendly flame-retardant antistatic rubber pads prepared in the examples and comparative examples

[0060] It can be seen from Table 1 that the data of Examples 1 to 6 are better than those of Comparative Examples 1 to 3 as a whole.

[0061] This is because, in embodiments 1 to 6, modified nitrile rubber is contained, and the phosphorus-containing group introduced therein reacts with free radicals at high temperature to generate phosphorus oxides, which can form a protective layer on the surface of the rubber pad to prevent heat transfer and oxygen diffusion, and significantly improve the heat resistance and flame retardancy of the antistatic rubber pad. At the same time, the addition of acrylic resin and polyurethane resin can improve the oil resistance and chemical corrosion resistance of the antistatic rubber pad. The combination of the above points can significantly increase its long-term durability while maintaining the excellent antistatic performance of the rubber pad, and the overall process materials are more environmentally friendly.

[0062] Comparative Example 1 does not introduce phosphorus-containing organic compounds, so the flame retardancy is the worst; Comparative Example 2 does not contain acrylic resin, and Comparative Example 3 does not contain polyurethane resin, so the long-term durability of Comparative Examples 2 and 3 is also worse.

[0063] Table 2 Comparison results of physical properties test of Example 1 and competing products

[0064] As shown in Table 2, the oil resistance volume change rate, water resistance volume change rate, relative volume wear, ozone aging resistance, and brittle temperature (-30°C) of Example 1 are all superior to those of competing products. This is because the addition of acrylic resin and polyurethane resin improves the oil resistance and chemical corrosion resistance of the antistatic rubber pad, and some other physical properties are also improved.

[0065] Table 3 Antistatic ability durability test under accelerated aging environment

[0066] As can be seen from Table 3, after the oven hot air aging test and the oil environment test, the antistatic ability of Example 1 is still valid, while the competing products are invalid. This is also because the phosphorus-containing groups introduced in Example 1 react with free radicals at high temperatures to generate phosphorus oxides, which can form a protective layer on the surface of the rubber pad to prevent heat transfer and oxygen diffusion, significantly improving the heat resistance and flame retardancy of the antistatic rubber pad. At the same time, the addition of acrylic resin and polyurethane resin can improve the oil resistance and chemical corrosion resistance of the antistatic rubber pad.

[0067] The above results show and describe the basic principles and main features of the present application as well as the advantages of the present application.

[0068] Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present application. Without departing from the spirit and scope of the present application, the present application may have various changes and improvements, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection sought in the present application is defined by the equivalents of the attached claims.

Claims

1. A long-lasting, environmentally friendly, flame-retardant, antistatic rubber mat, comprising a bottom static conductive layer (2) and a static dissipative layer (1) attached to one side of the static conductive layer (2); characterized in that: The static dissipative layer (1) comprises modified nitrile rubber, acrylic resin and a first auxiliary agent; the static conductive layer (2) comprises modified nitrile rubber, styrene-butadiene rubber, polyurethane resin and a second auxiliary agent; the modified nitrile rubber is obtained by using a Grignard reagent RMgBr to react with a cyanide group in the nitrile rubber to convert the cyanide group into a carbonyl group, and then using aldol condensation to introduce a phosphorus-containing organic compound into the nitrile rubber; wherein R in the Grignard reagent comprises any one of a methyl group, an ethyl group, an n-propyl group and an n-butyl group.

2. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 1, characterized in that: The structure of the phosphorus-containing organic compound is: 。 3. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 1, characterized in that: In the static dissipative layer (1), the first auxiliary agent includes an antistatic agent, paraffin oil, talcum powder, an antioxidant and a first accelerator; the mass ratio of the modified nitrile rubber, acrylic resin, antistatic agent, paraffin oil, talcum powder, antioxidant and the first accelerator is (25-50): (10-30): (2-10): (10-25): (4-9): (1-3): (3-10); in the static conductive layer (2), the second auxiliary agent includes conductive carbon black, carbon nanotubes, a plasticizer and a second accelerator; the mass ratio of the modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, plasticizer and the second accelerator is (20-40): (10-40): (15-30): (10-20): (5-10): (5-15): (3-10).

4. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 1, characterized in that: The structure of the modified nitrile rubber comprises: ； Wherein R includes any one of methyl, ethyl, n-propyl and n-butyl; x is an integer in the range of 60 to 150; and y is an integer in the range of 50 to 80.

5. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 3, characterized in that: The antioxidant includes one or more of diphenylamine, 2,6-di-tert-butyl-p-cresol, and triphenylphosphine.

6. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 3, characterized in that: The first accelerator includes one or more of N-cyclohexyl-2-benzothiazole sulfenamide, N-tert-butyl-2-benzothiazole sulfenamide, and 2-mercaptobenzothiazole.

7. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 3, characterized in that: The plasticizer includes one or more of dioctyl phthalate, dioctyl adipate, and diisooctyl sebacate.

8. The long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 3, characterized in that: The second accelerator includes one or more of tetramethylthiuram disulfide, zinc diethyldithiocarbamate, and zinc dimethyldithiocarbamate.

9. A method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to any one of claims 1 to 8, characterized in that: The following steps are involved: Add nitrile rubber and solvent into the reactor, stir at 20-30°C under nitrogen protection for 1-2 hours; Keep stirring at the same temperature under nitrogen, add the Grignard reagent dropwise into the reactor within 1 hour, and continue stirring for 10-12 hours; Continue to add the phosphorus-containing organic compound to the reactor and adjust the pH of the mixture in the reactor to 1-2; Add 4A molecular sieve powder into the reaction kettle, and continue stirring at 20-30° C. for 0.5-1 hour under nitrogen protection to obtain the modified nitrile rubber; The modified nitrile rubber and the acrylic resin are kneaded at 60-70° C. for 10-20 minutes, and then an antistatic agent, paraffin oil, talcum powder, an antioxidant, and a first accelerator are added, and the kneading is continued for 10-20 minutes, and then calendered to obtain a static dissipative layer (1) rubber material; The modified nitrile rubber, styrene butadiene rubber and polyurethane resin are kneaded at 60-70°C for 10-20 minutes, and then conductive carbon black, carbon nanotubes, plasticizer and second accelerator are added, and the kneading is continued for 10-20 minutes and then calendered to obtain a conductive layer (2) rubber material; The static conductive layer (2) adhesive is used as the bottom layer, and glue is applied to the side of the static conductive layer (2) for bonding, and then the static dissipative layer (1) adhesive is bonded to the static conductive layer (2), and hot pressing is performed at 130-150°C; The pressed rubber pad is placed in a vulcanizer and vulcanized under the conditions of 6-12 MPa and 150-180° C. to obtain the long-lasting and environmentally friendly flame-retardant antistatic rubber pad.

10. The method for preparing a long-lasting and environmentally friendly flame-retardant antistatic rubber pad according to claim 9, characterized in that: The solvent includes one or more of dichloromethane, toluene, and ethyl acetate; the mass ratio of the nitrile rubber, solvent, Grignard reagent, phosphorus-containing organic compound, and 4A molecular sieve powder is: (30-50): (20-40): (10-15): (5-10): (5-15); the glue includes one or two of nitrile latex and polyurethane adhesive.

Images