A long-lasting and environmentally friendly flame-retardant and anti-static rubber mat and its preparation method

Abstract

The present application discloses a long-lasting and environmentally friendly flame-retardant and antistatic rubber mat and a preparation method thereof, relating to the technical field of rubber mats. The long-lasting and environmentally friendly flame-retardant and antistatic rubber mat prepared in the present application comprises an underlying electrostatic conductive layer and an electrostatic dissipation layer adhered to one side of the electrostatic conductive layer. The electrostatic dissipation layer comprises modified nitrile rubber, acrylate resin and a first auxiliary agent; the electrostatic conductive layer comprises modified nitrile rubber, styrene-butadiene rubber, polyurethane resin and a second auxiliary agent. Among them, the modified nitrile rubber is obtained by reacting the Grignard reagent RMgBr with the cyano group in nitrile rubber to convert the cyano group into a carbonyl group, and then introducing a phosphorus-containing organic compound into the nitrile rubber by aldol condensation. The rubber mat prepared by using the modified nitrile rubber has excellent antistatic performance, and also has flame retardancy, is long-lasting and environmentally friendly, and has broad application prospects.

Description

Technical Field

[0001] The present application relates to the technical field of rubber pads, and specifically relates 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, the problem of static electricity has become increasingly prominent, posing a serious threat to the normal operation of electronic devices and the safety of personnel. As an important tool for eliminating static electricity, the market demand for antistatic rubber pads is continuously increasing. However, the existing antistatic rubber pads have certain limitations in terms of service life, environmental performance, and production processes. For example, some rubber pads are prone to aging and cracking during use, resulting in a decline in antistatic performance; at the same time, traditional production processes may use more toxic and harmful substances, causing potential harm to the environment and human health. Therefore, it is of great significance to develop a long-lasting, environmentally friendly flame-retardant and antistatic rubber pad and a preparation method thereof.

[0003] Chinese Patent with Publication No. CN 112358665 A discloses an antistatic rubber composition, an antistatic rubber floor and a preparation method thereof. The antistatic rubber composition includes: 100 parts by weight of nitrile rubber, 8-15 parts by weight of ethylene-acrylate-glycidyl methacrylate copolymer, 0.5-3 parts by weight of poly-pyridine-coated aluminum-doped zinc oxide composite material, 3-6 parts by weight of vulcanization accelerator, 10-20 parts by weight of flame retardant and 20-30 parts by weight of reinforcing filler; wherein, the poly-pyridine-coated aluminum-doped zinc oxide composite material includes aluminum-doped zinc oxide with a particle size of 40-150 nm and polypyrrole coated on its surface, the polypyrrole accounts for 5-20% of the weight of the aluminum-doped zinc oxide, and in terms of aluminum oxide, the doping amount of aluminum in the aluminum-doped zinc oxide is 1-3% by weight. 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 the antistatic rubber floor prepared by this solution is still relatively low, and the improvement of its flame retardant performance mainly relies on the physical doping of the flame retardant rather than introducing flame retardant components through chemical reactions. In addition, this solution does not specifically reflect the performance of the prepared antistatic rubber floor related to long-term use such as aging resistance and corrosion resistance, 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 and antistatic rubber mat and a preparation method thereof. By reacting the Grignard reagent RMgBr with the cyano group in nitrile rubber, the cyano group is converted into a carbonyl group, and then a phosphorus-containing organic compound is introduced into the nitrile rubber by aldol condensation to obtain modified nitrile rubber. Then, using the modified nitrile rubber as the main raw material, conductive layer rubber compound and electrostatic dissipation layer rubber compound are prepared, and further a long-lasting and environmentally friendly flame-retardant and antistatic rubber mat is obtained. The long-lasting and environmentally friendly flame-retardant and antistatic rubber mat has excellent antistatic performance, and also has flame retardancy, is long-lasting and environmentally friendly, and has broad application prospects.

[0006] To achieve the above object, the present application adopts the following technical solutions:

[0007] In the first aspect, the present application provides a long-lasting and environmentally friendly flame-retardant and antistatic rubber mat, including a conductive layer (2) at the bottom layer and an electrostatic dissipation layer (1) attached to one side of the conductive layer (2); characterized in that the electrostatic dissipation layer (1) includes modified nitrile rubber, acrylate resin and a first auxiliary agent; the first auxiliary agent includes an antistatic agent, paraffin oil, talcum powder, antioxidant and a first accelerator; the conductive layer (2) includes modified nitrile rubber, styrene-butadiene rubber, polyurethane resin and a second auxiliary agent; the second auxiliary agent includes conductive carbon black, carbon nanotubes, plasticizer and a second accelerator; the modified nitrile rubber is obtained by reacting the Grignard reagent RMgBr with the cyano group in nitrile rubber to convert the cyano group into a carbonyl group, and then introducing a phosphorus-containing organic compound into the nitrile rubber by aldol condensation; wherein, R in the Grignard reagent includes any one of methyl, ethyl, n-propyl and n-butyl.

[0008] In the second aspect, the present application provides a preparation method of a long-lasting and environmentally friendly flame-retardant and antistatic rubber mat, including:

[0009] Adding nitrile rubber and a solvent into a reaction kettle, stirring at 20-30 °C under nitrogen protection for 1-2 hours;

[0010] Maintaining stirring under nitrogen at the same temperature, and dropping the Grignard reagent into the reaction kettle within 1 hour, and continuing to stir for 10-12 hours;

[0011] Continuing to add a phosphorus-containing organic compound into the reaction kettle, and adjusting the pH of the mixture in the reaction kettle to 1-2;

[0012] Adding 4A molecular sieve powder into the reaction kettle, and continuing to stir at 20-30 °C under nitrogen protection for 0.5-1 hour to obtain the modified nitrile rubber;

[0013] Mix the modified nitrile rubber and acrylate resin at 60 - 70 °C for 10 - 20 min, then add paraffin oil, talcum powder, antioxidant, and the first accelerator, and continue mixing for 10 - 20 min before calendering to obtain the static dissipation layer rubber compound;

[0014] Mix the modified nitrile rubber, styrene - butadiene rubber and polyurethane resin at 60 - 70 °C for 10 - 20 min, then add conductive carbon black, carbon nanotubes, plasticizer, and the second accelerator, and continue mixing for 10 - 20 min before calendering to obtain the static conductive layer rubber compound;

[0015] Use the static conductive layer rubber compound as the bottom layer, apply glue on the side of the static conductive layer for lamination, then laminate the static dissipation layer rubber compound on the static conductive layer, and perform hot pressing lamination at 130 - 150 °C;

[0016] Put the laminated rubber pad into a vulcanizer and perform vulcanization treatment under the conditions of 6 - 12 MPa and 150 - 180 °C to obtain the long - term environmentally friendly flame - retardant and antistatic rubber pad.

[0017] Beneficial technical effects:

[0018] In this application, through a unique synthesis method, the Grignard reagent RMgBr reacts with the cyano group in nitrile rubber to convert the cyano group into a carbonyl group, and then the aldol condensation is used to introduce a phosphorus - containing organic compound into nitrile rubber to form a phosphorus - containing group, thus obtaining the modified nitrile rubber; then using the modified nitrile rubber as the main raw material to prepare the static conductive layer rubber compound and the static dissipation layer rubber compound, and further obtaining the long - term environmentally friendly flame - retardant and antistatic rubber pad.

[0019] The phosphorus - containing group introduced into the modified nitrile rubber of this application through chemical reactions will not show the phenomenon of uneven distribution caused by directly adding phosphorus - containing compounds in the polymer, nor the problems of physical changes such as easy volatilization, dissolution or migration during processing or use. Moreover, the phosphorus - containing group introduced through chemical reactions reacts with free radicals at high temperatures to generate phosphorus oxides, and these phosphorus oxides 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 acrylate 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 flame retardancy and service life while maintaining the excellent antistatic performance of the rubber pad, and the overall process materials are environmentally friendly, having broad application prospects. Brief description of the drawings

[0020] Figure 1 is a schematic structural diagram of the long - term environmentally friendly flame - retardant and antistatic rubber pad.

[0021] Figure 2 is a schematic chemical reaction diagram for preparing the modified nitrile rubber.

[0022] Figure 3 It is a schematic flow chart for preparing a long - lasting, environmentally friendly flame - retardant and antistatic rubber mat.

[0023] Figure 4 It is the chemical structural formula of the modified nitrile rubber prepared in Example 1.

[0024] Reference numerals: 1. Electrostatic dissipation layer; 2. Electrostatic conduction layer. Detailed implementation manners

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clearer and more understandable, the following will further elaborate on this application in combination with embodiments. However, it should not be understood that the scope of this application is limited to the following examples. Without departing from the above - mentioned method concept of this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

[0026] In this application, the terms used are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0027] In this application, the singular forms of "is", "or", "a", "any one", "any kind" and "the" are intended to include the plural forms, unless the context clearly indicates otherwise.

[0028] In addition, if the terms "first" and "second" appear, they are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] In a first aspect, this application provides a long - lasting, environmentally friendly flame - retardant and antistatic rubber mat, which includes an electrostatic conduction layer (2) at the bottom layer and an electrostatic dissipation layer (1) attached to one side of the electrostatic conduction layer (2); characterized in that the electrostatic dissipation layer (1) includes modified nitrile rubber, acrylate resin and a first additive; the first additive includes an antistatic agent, paraffin oil, talcum powder, antioxidant and a first accelerator; the electrostatic conduction layer (2) includes modified nitrile rubber, styrene - butadiene rubber, polyurethane resin and a second additive; the second additive includes conductive carbon black, carbon nanotubes, plasticizer and a second accelerator; the modified nitrile rubber is obtained by reacting the cyano group in nitrile rubber with Grignard reagent RMgBr to convert the cyano group into a carbonyl group, and then introducing a phosphorus - containing organic compound into the nitrile rubber by aldol condensation; wherein, R in the Grignard reagent includes any one of methyl, ethyl, n - propyl and n - butyl.

[0030] In a possible implementation manner, R in the Grignard reagent includes any one of methyl, ethyl, n - propyl and n - butyl.

[0031] In a possible implementation, the structure of the phosphorus-containing organic compound is as follows:

[0032] .

[0033] In a possible implementation, in the electrostatic dissipation layer 1, the mass ratio of the modified nitrile rubber, acrylate 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).

[0034] In a possible implementation, in the conductive electrostatic layer 2, 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).

[0035] In a possible implementation, the structure of the modified nitrile rubber includes:

[0036] ;

[0037] wherein R includes any one of methyl, ethyl, n-propyl, and n-butyl; x is an integer in the range of 60-150; y is an integer in the range of 50-80.

[0038] In a possible implementation, the antioxidant includes one or more of diphenylamine, 2,6-di-tert-butyl-p-cresol, and triphenylphosphine.

[0039] 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.

[0040] In a possible implementation, the plasticizer includes one or more of dioctyl phthalate, dioctyl adipate, and diisooctyl sebacate.

[0041] In a possible implementation, the second accelerator includes one or more of tetramethylthiuram disulfide, zinc diethyldithiocarbamate, and zinc dimethyldithiocarbamate.

[0042] Second, the present application provides a preparation method for a long-lasting and environmentally friendly flame-retardant and antistatic rubber mat, as Figure 3 shown, including:

[0043] Adding nitrile rubber and a solvent to a reaction kettle, stirring at 20-30°C under nitrogen protection for 1-2 hours;

[0044] Stir under nitrogen at the same temperature, and add the Grignard reagent dropwise to the reaction kettle within 1 hour, and continue stirring for 10 to 12 hours;

[0045] Continue to add the phosphorus-containing organic compound to the reaction kettle, and adjust the pH of the mixture in the reaction kettle to 1 to 2;

[0046] Add 4A molecular sieve powder to the reaction kettle, and continue stirring under nitrogen protection at 20 to 30 °C for 0.5 to 1 hour to obtain the modified nitrile rubber;

[0047] Mix the modified nitrile rubber and acrylate resin at 60 to 70 °C for 10 to 20 min, then add paraffin oil, talcum powder, antioxidant, and the first accelerator, and continue mixing for 10 to 20 min before calendering to obtain the static dissipation layer 1 rubber compound;

[0048] Mix the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin at 60 to 70 °C for 10 to 20 min, then add conductive carbon black, carbon nanotubes, plasticizer, and the second accelerator, and continue mixing for 10 to 20 min before calendering to obtain the static conductive layer 2 rubber compound;

[0049] Use the static conductive layer 2 rubber compound as the bottom layer, and apply glue on the side of the static conductive layer 2 for lamination, then laminate the static dissipation layer 1 rubber compound on the static conductive layer 2, and perform hot pressing at 130 to 150 °C;

[0050] Put the laminated rubber pad into a vulcanizer and perform vulcanization treatment under the conditions of 6 to 12 MPa and 150 to 180 °C to obtain the long-lasting and environmentally friendly flame-retardant and anti-static rubber pad.

[0051] In a possible implementation, the solvent includes one or more of dichloromethane, toluene, and ethyl acetate.

[0052] In a possible implementation, the mass ratio of the nitrile rubber, solvent, Grignard reagent, phosphorus-containing organic compound, and 4A molecular sieve powder is: (30 to 50): (20 to 40): (10 to 15): (5 to 10): (5 to 15).

[0053] In a possible implementation, the glue includes one or two of nitrile latex and polyurethane adhesive.

[0054] The following will specifically describe a long-lasting and environmentally friendly flame-retardant and anti-static rubber pad and its preparation method provided by the present application in combination with different embodiments.

[0055] Example 1:

[0056] As Figure 3As shown, a preparation method of a long-acting environmentally friendly flame-retardant and antistatic rubber mat includes the following steps:

[0057] 1. Add nitrile rubber and dichloromethane into a reaction kettle, stir at 25°C under nitrogen protection for 1.5 hours;

[0058] 2. Then continue stirring under the same temperature and nitrogen, and add the Grignard reagent with the structure of CH 3 MgBr dropwise into the reaction kettle within 1 hour, and continue stirring for 11 hours;

[0059] 3. Subsequently, add a phosphorus-containing organic compound into the reaction kettle and adjust the pH to 1.5;

[0060] 4. Then add 4A molecular sieve powder into the reaction kettle and continue stirring at 25°C for 0.5 hours to obtain modified nitrile rubber, and its chemical structural formula is as Figure 4 shown;

[0061] In steps 1 to 4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH 3 MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is: 30:40:15:7:8;

[0062] 5. Then mix the modified nitrile rubber and acrylate resin at 65°C for 15 minutes, add an antistatic agent, paraffin oil, talc powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide, continue mixing for 15 minutes and then calender to obtain the static dissipation layer 1 rubber compound;

[0063] The mass ratio of modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talc powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide is 40:25:5:15:5:2:8;

[0064] 6. At the same time, mix the modified nitrile rubber, styrene-butadiene rubber, and polyurethane resin at 65°C for 15 minutes, add conductive carbon black, carbon nanotubes, dioctyl phthalate, and tetramethylthiuram disulfide, continue mixing for 15 minutes and then calender to obtain the conductive layer 2 rubber compound;

[0065] 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;

[0066] 7. Then use the conductive layer 2 rubber compound as the bottom layer, coat nitrile latex on the side for bonding, then bond the static dissipation layer 1 rubber compound on it, and perform hot pressing at 140°C;

[0067] 8. Finally, place the laminated rubber pad into a vulcanizer and conduct vulcanization treatment under the conditions of 9 MPa and 165 °C to obtain a long-lasting, environmentally friendly flame-retardant and anti-static rubber pad.

[0068] Example 2:

[0069] As Figure 3 shown, a preparation method of a long-lasting, environmentally friendly flame-retardant and anti-static rubber pad includes the following steps:

[0070] 1. Add nitrile rubber and toluene into a reaction kettle, stir at 28 °C under nitrogen protection for 2 hours;

[0071] 2. Then continue to stir under nitrogen at the same temperature, and drop the Grignard reagent with the structure of CH 3 CH 2 MgBr into the reaction kettle within 1 hour, and continue to stir for 10 hours;

[0072] 3. Subsequently, add a phosphorus-containing organic compound into the reaction kettle and adjust the pH to 1;

[0073] 4. Then add 4A molecular sieve powder into the reaction kettle and continue to stir at 28 °C for 1 hour to obtain modified nitrile rubber;

[0074] In steps 1-4, the mass ratio of nitrile rubber, toluene, Grignard reagent CH 3 CH 2 MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is: 40:30:12:8:10;

[0075] 5. After that, knead the modified nitrile rubber and acrylate resin at 70 °C for 18 min, then add an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide, and continue to knead for 18 min and then calender to obtain the electrostatic dissipation layer 1 rubber compound;

[0076] The mass ratio of modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide is 36:20:10:18:4:2:10;

[0077] 6. At the same time, knead the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin at 70 °C for 18 min, then add conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate, continue to knead for 18 min and then calender to obtain the electrostatic conductive layer 2 rubber compound;

[0078] The mass ratio of the 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;

[0079] 7. Then, take the conductive static layer 2 rubber compound as the bottom layer, apply polyurethane adhesive on the side for lamination, then laminate the static dissipation layer 1 rubber compound on it, and perform hot pressing at 135°C.

[0080] 8. Finally, put the laminated rubber pad into a vulcanizer and perform vulcanization treatment under the conditions of 7 MPa and 170°C to obtain a long-lasting, environmentally friendly flame-retardant and antistatic rubber pad.

[0081] Example 3:

[0082] As Figure 3 shown, a preparation method of a long-lasting, environmentally friendly flame-retardant and antistatic rubber pad includes the following steps:

[0083] 1. Add nitrile rubber and ethyl acetate to a reaction kettle, stir at 30°C under nitrogen protection for 1 hour;

[0084] 2. Then continue stirring under nitrogen at the same temperature, and drop the Grignard reagent with the structure of CH 3 CH 2 CH 2 MgBr into the reaction kettle within 1 hour, and continue stirring for 12 hours;

[0085] 3. Subsequently, add a phosphorus-containing organic compound to the reaction kettle and adjust the pH to 2;

[0086] 4. Then add 4A molecular sieve powder to the reaction kettle and continue stirring at 30°C for 0.5 hour to obtain the modified nitrile rubber;

[0087] In steps 1 to 4, the mass ratio of nitrile rubber, ethyl acetate, Grignard reagent CH 3 CH 2 CH 2 MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is: 45:25:12:8:10;

[0088] 5. Then mix the modified nitrile rubber and acrylate resin at 60°C for 20 min, add an antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and 2-mercaptobenzothiazole, continue mixing for 20 min, and then perform calendering to obtain the static dissipation layer 1 rubber compound;

[0089] The mass ratio of the modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and 2-mercaptobenzothiazole is 32:20:10:18:8:2:10;

[0090] 6. At the same time, mix modified nitrile rubber, styrene-butadiene rubber and polyurethane resin at 60 °C for 20 min, then add conductive carbon black, carbon nanotubes, diisooctyl sebacate and zinc dimethyldithiocarbamate, continue to mix for 20 min and then calender to obtain the conductive static layer 2 rubber compound;

[0091] 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;

[0092] 7. Then use the conductive static layer 2 rubber compound as the bottom layer, coat nitrile latex on the side for bonding, then bond the static dissipation layer 1 rubber compound on it, and carry out hot pressing at 145 °C;

[0093] 8. Finally, put the pressed rubber pad into a vulcanizer and carry out vulcanization treatment under the conditions of 12 MPa and 155 °C to obtain a long-lasting, environmentally friendly flame-retardant and antistatic rubber pad.

[0094] Example 4:

[0095] As Figure 3 shown, a preparation method of a long-lasting, environmentally friendly flame-retardant and antistatic rubber pad includes the following steps:

[0096] 1. Add nitrile rubber and dichloromethane into a reaction kettle, stir at 24 °C under nitrogen protection for 2 hours;

[0097] 2. Then continue to stir under nitrogen at the same temperature, and add the Grignard reagent with the structure of CH 3 CH 2 CH 2 CH 2 MgBr dropwise into the reaction kettle within 1 hour, and continue to stir for 10.5 hours;

[0098] 3. Subsequently, add a phosphorus-containing organic compound into the reaction kettle and adjust the pH to 1;

[0099] 4. Then add 4A molecular sieve powder into the reaction kettle and continue to stir at 24 °C for 1 hour to obtain modified nitrile rubber;

[0100] In steps 1 to 4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH 3 CH 2 CH 2 CH 2 MgBr, phosphorus-containing organic compound, and 4A molecular sieve powder is: 50:20:12:8:10.

[0101] 5. After that, the modified nitrile rubber and acrylate resin are kneaded at 67°C for 16 min, and then antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-tert-butyl-2-benzothiazole sulfenamide are added, and kneading is continued for 16 min before calendering to obtain the static dissipation layer 1 rubber compound;

[0102] The mass ratio of the modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-tert-butyl-2-benzothiazole sulfenamide is 35:28:8:12:7:3:7;

[0103] 6. Meanwhile, the modified nitrile rubber, styrene-butadiene rubber, and polyurethane resin are kneaded at 67°C for 18 min, and then conductive carbon black, carbon nanotubes, dioctyl phthalate, and zinc dimethyldithiocarbamate are added, and kneading is continued for 18 min before calendering to obtain the static conductive layer 2 rubber compound;

[0104] The mass ratio of the 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;

[0105] 7. After that, the static conductive layer 2 rubber compound is used as the bottom layer, and polyurethane adhesive is coated on the side for bonding, and then the static dissipation layer 1 rubber compound is bonded thereto, and hot pressing is carried out at 150°C;

[0106] 8. Finally, the pressed rubber pad is put into a vulcanizer and vulcanized under the conditions of 10 MPa and 150°C to obtain a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad.

[0107] Example 5:

[0108] As Figure 3 shown, a preparation method of a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad includes the following steps:

[0109] 1. Add nitrile rubber and ethyl acetate to a reaction kettle, stir at 25°C under nitrogen protection for 1.2 hours;

[0110] 2. Then continue stirring under nitrogen at the same temperature, and add the Grignard reagent with the structure of CH 3 CH 2 MgBr dropwise into the reaction kettle within 1 hour, and continue stirring for 10 hours;

[0111] 3. Subsequently, add a phosphorus-containing organic compound to the reaction kettle and adjust the pH to 1.2;

[0112] 4. Then add 4A molecular sieve powder to the reaction kettle and continue stirring at 25°C for 0.5 hour to obtain the modified nitrile rubber;

[0113] In Steps 1 to 4, the mass ratio of nitrile rubber, ethyl acetate, Grignard reagent CH 3 CH 2 MgBr, the phosphorus-containing organic compound, and the 4A molecular sieve powder is: 40:25:10:10:15.

[0114] 5. Then, the modified nitrile rubber and acrylate resin are kneaded at 62°C for 15 minutes, and then antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and N-cyclohexyl-2-benzothiazole sulfenamide are added, and kneading is continued for 15 minutes followed by calendering to obtain the static dissipation layer 1 rubber compound;

[0115] The mass ratio of the modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and N-cyclohexyl-2-benzothiazole sulfenamide is 35:25:10:20:5:2:3;

[0116] 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber, and polyurethane resin are kneaded at 62°C for 15 minutes, and then conductive carbon black, carbon nanotubes, bis(2-ethylhexyl) sebacate, and tetramethylthiuram disulfide are added, and kneading is continued for 15 minutes followed by calendering to obtain the electrostatic conductive layer 2 rubber compound;

[0117] The mass ratio of the modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, bis(2-ethylhexyl) sebacate, and tetramethylthiuram disulfide is 30:15:20:16:9:7:3;

[0118] 7. Then, the electrostatic conductive layer 2 rubber compound is used as the bottom layer, and nitrile latex is coated on the side for lamination, and then the static dissipation layer 1 rubber compound is laminated on it, and hot pressing is carried out at 145°C;

[0119] 8. Finally, the laminated rubber pad is put into a vulcanizer and vulcanized under the conditions of 6 MPa and 180°C to obtain a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad.

[0120] Example 6:

[0121] As Figure 3 shown, a preparation method of a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad includes the following steps:

[0122] 1. Add nitrile rubber and toluene into a reaction kettle, stir at 20°C under nitrogen protection for 1.5 hours;

[0123] 2. Then continue stirring under nitrogen at the same temperature, and the structure is CH 3 CH 2 CH 2 CH 2The Grignard reagent of MgBr was added dropwise to the reaction kettle within 1 hour, and stirring was continued for 10 hours;

[0124] 3. Subsequently, an organophosphorus compound was added to the reaction kettle, and the pH was adjusted to 1;

[0125] 4. Then, 4A molecular sieve powder was added to the reaction kettle, and stirring was continued at 20 °C for 1 hour to obtain the modified nitrile rubber;

[0126] In Steps 1 to 4, the mass ratio of nitrile rubber, toluene, the Grignard reagent CH 3 CH 2 CH 2 CH 2 MgBr, the organophosphorus compound, and the 4A molecular sieve powder was 45:20:15:10:10.

[0127] 5. Thereafter, the modified nitrile rubber and acrylate resin were kneaded at 70 °C for 10 min, and then an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide were added. Kneading was continued for 10 min and then calendering was performed to obtain the static dissipation layer 1 stock;

[0128] The mass ratio of the modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide was 30:30:9:12:9:3:7;

[0129] 6. At the same time, the modified nitrile rubber, styrene-butadiene rubber, and polyurethane resin were kneaded at 70 °C for 10 min, and then conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate were added. Kneading was continued for 10 min and then calendering was performed to obtain the static conductive layer 2 stock;

[0130] The mass ratio of the modified nitrile rubber, styrene-butadiene rubber, polyurethane resin, conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate was 35:15:15:13:7:9:6;

[0131] 7. Thereafter, the static conductive layer 2 stock was used as the bottom layer, and a polyurethane adhesive was applied to the side for lamination. Then, the static dissipation layer 1 stock was laminated thereon, and hot pressing was performed at 150 °C;

[0132] 8. Finally, the laminated rubber pad was placed in a vulcanizer and vulcanized under the conditions of 7 MPa and 175 °C to obtain a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad.

[0133] Comparative Example 1:

[0134] A preparation method of a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad includes the following steps:

[0135] 1. Add nitrile rubber and dichloromethane into the reaction kettle, stir at 25°C under nitrogen protection for 1.5 hours;

[0136] 2. Then continue to stir under nitrogen at the same temperature, and drop the Grignard reagent with the structure of CH3MgBr into the reaction kettle within 1 hour, and continue to stir for 11 hours;

[0137] 3. Subsequently, add ethylene glycol into the reaction kettle and adjust the pH to 1.5;

[0138] 4. Then add 4A molecular sieve powder into the reaction kettle and continue to stir at 25°C for 0.5 hour to obtain the modified nitrile rubber, and its chemical structural formula is as Figure 4 shown;

[0139] In steps 1-4, the mass ratio of nitrile rubber, dichloromethane, Grignard reagent CH3MgBr, ethylene glycol, and 4A molecular sieve powder is: 30:40:15:7:8;

[0140] 5. Then mix the modified nitrile rubber and acrylate resin at 65°C for 15 min, add antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide, continue to mix for 15 min and then calender to obtain the static dissipation layer 1 rubber compound;

[0141] The mass ratio of modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, diphenylamine, and N-cyclohexyl-2-benzothiazole sulfenamide is 40:25:5:15:5:2:8;

[0142] 6. At the same time, mix the modified nitrile rubber, styrene-butadiene rubber and polyurethane resin at 65°C for 15 min, add conductive carbon black, carbon nanotubes, dioctyl phthalate, and tetramethylthiuram disulfide, continue to mix for 15 min and then calender to obtain the static conductive layer 2 rubber compound;

[0143] 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;

[0144] 7. Then use the static conductive layer 2 rubber compound as the bottom layer, coat nitrile latex on the side for lamination, then laminate the static dissipation layer 1 rubber compound on it, and perform hot pressing at 140°C;

[0145] 8. Finally, put the laminated rubber pad into a vulcanizer and perform vulcanization treatment under the conditions of 9 MPa and 165°C to obtain a long-lasting and environmentally friendly flame-retardant and antistatic rubber pad.

[0146] Comparative Example 2:

[0147] A preparation method of a long - acting environmentally friendly flame - retardant and antistatic rubber mat, comprising the following steps:

[0148] 1. Add nitrile rubber and ethyl acetate into a reaction kettle, stir at 30°C under nitrogen protection for 1 hour;

[0149] 2. Then continue to stir under nitrogen at the same temperature, and drop the Grignard reagent with the structure of CH3CH2CH2MgBr into the reaction kettle within 1 hour, and continue to stir for 12 hours;

[0150] 3. Subsequently, add a phosphorus - containing organic compound into the reaction kettle and adjust the pH to 2;

[0151] 4. Then add 4A molecular sieve powder into the reaction kettle and continue to stir at 30°C for 0.5 hour to obtain modified nitrile rubber;

[0152] In steps 1 - 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;

[0153] 5. After that, knead the modified nitrile rubber at 60°C for 20 min, then add an antistatic agent, paraffin oil, talcum powder, triphenylphosphine, 2 - mercaptobenzothiazole, continue to knead for 20 min and then calender to obtain the static dissipation layer 1 rubber compound;

[0154] The mass ratio of modified nitrile rubber, antistatic agent, paraffin oil, talcum powder, triphenylphosphine, and 2 - mercaptobenzothiazole is 52:10:18:8:2:10;

[0155] 6. At the same time, knead the modified nitrile rubber, styrene - butadiene rubber, and polyurethane resin at 60°C for 20 min, then add conductive carbon black, carbon nanotubes, diisooctyl sebacate, and zinc dimethyldithiocarbamate, continue to knead for 20 min and then calender to obtain the conductive layer 2 rubber compound;

[0156] 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;

[0157] 7. After that, use the conductive layer 2 rubber compound as the bottom layer, coat nitrile latex on the side for lamination, then laminate the static dissipation layer 1 rubber compound on it, and perform hot press lamination at 145°C;

[0158] 8. Finally, put the laminated rubber pad into a vulcanizer and conduct vulcanization treatment under the conditions of 12 MPa and 155 °C, then a long-lasting, environmentally friendly flame-retardant and anti-static rubber pad is obtained.

[0159] Comparative Example 3:

[0160] A preparation method of a long-lasting, environmentally friendly flame-retardant and anti-static rubber pad, comprising the following steps:

[0161] 1. Add nitrile rubber and toluene into a reaction kettle, stir at 20 °C under nitrogen protection for 1.5 hours;

[0162] 2. Then continue to stir under the same temperature and nitrogen, and drop the Grignard reagent with the structure of CH3CH2CH2CH2MgBr into the reaction kettle within 1 hour, and continue to stir for 10 hours;

[0163] 3. Subsequently, add a phosphorus-containing organic compound into the reaction kettle and adjust the pH to 1;

[0164] 4. Then add 4A molecular sieve powder into the reaction kettle and continue to stir at 20 °C for 1 hour to obtain modified nitrile rubber;

[0165] 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.

[0166] 5. After that, mix the modified nitrile rubber and acrylate resin at 70 °C for 10 min, then add an antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide, and continue to mix for 10 min and then calender to obtain the electrostatic dissipation layer 1 rubber compound;

[0167] The mass ratio of modified nitrile rubber, acrylate resin, antistatic agent, paraffin oil, talcum powder, 2,6-di-tert-butyl-p-cresol, and N-tert-butyl-2-benzothiazole sulfenamide is 30:30:9:12:9:3:7;

[0168] 6. At the same time, mix the modified nitrile rubber at 70 °C for 10 min, then add conductive carbon black, carbon nanotubes, dioctyl adipate, and zinc diethyldithiocarbamate, continue to mix for 10 min and then calender to obtain the electrostatic conductive layer 2 rubber compound;

[0169] 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;

[0170] 7. After that, take the static conductive layer 2 compound as the bottom layer, coat polyurethane adhesive on the side for lamination, then laminate the static dissipation layer 1 compound on it, and perform hot press lamination at 150 °C.

[0171] 8. Finally, put the laminated rubber pad into a vulcanizer and perform vulcanization treatment under the conditions of 7 MPa and 175 °C, then a long-lasting, environmentally friendly flame-retardant and anti-static rubber pad is obtained.

[0172] Refer to GB / T 1690-2010, and conduct a liquid resistance test on the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application by the liquid resistance test method, and calculate the mass reduction ratio after immersion in mineral oil.

[0173] And refer to GB / T 3512-2014, and conduct an aging resistance test on the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application by the hot air accelerated aging test, and calculate the tensile strength retention rate after aging.

[0174] Through the above two points, the long-lasting durability of the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application is reflected.

[0175] Refer to GB / T 8624-2012, and conduct a flame retardancy test on the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application to reflect its flame retardant performance.

[0176] Refer to GB / T 11210-2014, and conduct a resistance test on the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application to reflect its anti-static performance.

[0177] In addition, the long-lasting, environmentally friendly flame-retardant and anti-static rubber pad prepared in this application has also been subjected to relevant performance test comparisons with peer competitors, as shown in Table 2 and Table 3.

[0178] Table 1 Performance test results of the long-lasting, environmentally friendly flame-retardant and anti-static rubber pads prepared in the examples and comparative examples

[0179]

[0180] As can be seen from Table 1, the data of Examples 1-6 are overall better than those of Comparative Examples 1-3.

[0181] This is because the modified nitrile rubber is contained in Examples 1 to 6, and the introduced phosphorus-containing groups react with free radicals at high temperatures to generate phosphorus oxides. These phosphorus oxides 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 acrylate resin and polyurethane resin can enhance 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 relatively environmentally friendly.

[0182] However, no phosphorus-containing organic compound was introduced in Comparative Example 1, so its flame retardancy is the worst; acrylate resin is not contained in Comparative Example 2, and polyurethane resin is not contained in Comparative Example 3. Therefore, the long-term durability of Comparative Example 2 and Comparative Example 3 is also worse.

[0183] Table 2 Comparison results of physical property tests between Example 1 and peer competitors

[0184]

[0185] As can be seen from Table 2, the oil volume change rate, water volume change rate, relative volume wear amount, ozone aging resistance, and brittle temperature (-30°C) of Example 1 are all better than those of peer competitors. This is because the addition of acrylate resin and polyurethane resin has improved the oil resistance and chemical corrosion resistance of the antistatic rubber pad, and some other physical properties have also been improved.

[0186] Table 3 Durability test of antistatic ability in an accelerated aging environment

[0187]

[0188] As can be seen from Table 3, after the oven hot air aging test and the oil environment test, the qualified determination of the antistatic ability of Example 1 is still valid, while that of peer competitors is invalid. This is also because the introduced phosphorus-containing groups in Example 1 react with free radicals at high temperatures to generate phosphorus oxides. These phosphorus oxides 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 acrylate resin and polyurethane resin can enhance the oil resistance and chemical corrosion resistance of the antistatic rubber pad.

[0189] The above results show and describe the basic principles, main features, and advantages of the present application.

[0190] Those skilled in the art should understand that this application is not limited by the above embodiments. What is described in the above embodiments and the specification is only to illustrate the principle of this application. Without departing from the spirit and scope of this application, this application will also have various changes and improvements, and these changes and improvements all fall within the scope of this application claimed. The scope of protection claimed by this application is defined by the equivalents of the appended 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 first auxiliary agent comprises an antistatic agent, paraffin oil, talcum powder, an antioxidant and a first accelerator; the static conductive layer (2) comprises modified nitrile rubber, styrene-butadiene rubber, polyurethane resin and a second auxiliary agent; the second auxiliary agent comprises conductive carbon black, carbon nanotubes, a plasticizer and a second accelerator; the modified nitrile rubber is obtained by reacting the cyanide group in the nitrile rubber with a Grignard reagent RMgBr to convert the cyanide group into a carbonyl group, and then introducing a phosphorus-containing organic compound into the nitrile rubber by aldol condensation; 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 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); in the static conductive layer (2), 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).

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.

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