Synthetic method and application of special dispersing agent for polar rubber carbon black

Abstract

The invention discloses a synthesis method and application of a special dispersant for polar rubber carbon black, and relates to the technical field of rubber auxiliary materials. The synthesis method of the special dispersant for polar rubber carbon black comprises the following steps: in an inert protective gas atmosphere, carrying out heat preservation reaction on polyether amine, absolute ethyl alcohol and an acrylate monomer to obtain an intermediate I; in an inert protective gas atmosphere, carrying out heat preservation reaction on the intermediate I, a catalyst I and fatty diacid to obtain an intermediate II; and in an inert protective gas atmosphere, carrying out heat preservation reaction on the intermediate II, a catalyst II and fatty monoacid to obtain the special dispersing agent for the carbon black for the polar rubber. The prepared special dispersant for polar rubber carbon black has good precipitation resistance in polar rubber such as nitrile rubber, and can uniformly disperse the carbon black and improve the mechanical properties and apparent properties of the rubber.

Description

Technical Field

[0001] The invention relates to the technical field of rubber auxiliary materials, and in particular to a synthesis method and application of a special dispersant for polar rubber carbon black. Background Art

[0002] Existing rubber products have a large amount of inorganic fillers in the rubber compound mixing, especially carbon black is one of the commonly used fillers for reinforcing rubber. The purpose of adding a large amount of carbon black is, on the one hand, to reduce the rubber content of rubber to reduce the production cost of rubber products, and on the other hand, carbon black is a reinforcing material for rubber, which can improve the reinforcement performance of tires, such as reducing the wear coefficient of tires, reinforcing the anti-cracking performance of sidewall rubber, and improving the hardness of some rubber products as well as anti-cracking and light aging performance. Carbon black is a kind of amorphous carbon. It is a light, loose and extremely fine black powder with a particle size of micro-nano level, and its specific surface area is very large, ranging from 10-3000m 2 / g, and the viscosity of the rubber material is relatively high, so a large amount of carbon black filling also brings problems such as difficulty in dispersing and uneven dispersion in rubber compound mixing. At present, the main means to solve the dispersion problem of carbon black in rubber are: first, prolonging the mixing time of the rubber compound, which in turn causes a great waste of energy (electricity and steam). The Mooney viscosity of the rubber compound is larger when the mixing time is extended, and the rubber compound extrusion rate is lower, resulting in technical problems such as waste of rubber and inability to improve production efficiency. Second, in the production of rubber products, a carbon black dispersant is added. The patent (patent number: CN103724665B) discloses a carbon black dispersant for rubber products and a preparation method thereof, which is characterized in that the carbon black dispersant is made of the following raw materials in the following weight ratio: 25-35 parts of pentaerythritol, 15-25 parts of oxidized polyethylene wax, 12-18 parts of zinc stearate, 18-25 parts of talc, 8-15 parts of three-line oil, and 1-5 parts of antioxidant 998-A. The patent (patent number: CN1101418C) discloses a carbon black dispersant for rubber and its production method. Such a carbon black dispersant is also compounded with a variety of lubricants. The patent (patent number: CN116715583A) discloses a carbon black special super dispersant and a carbon black masterbatch prepared therefrom. The carbon black special super dispersant is prepared by heating the purified 5-hydroxy dodecanoic acid glyceride with wood tar acid, mercaptoethanol, and peroxy dicarbonate at 110-130°C. The patent (patent number: CN107573702B) discloses a carbon black dispersant, its preparation method and application, as well as a rubber composition and vulcanized rubber and its preparation method. The carbon black dispersant contains stearic acid glyceryl, zinc stearate, stearic acid and microcrystalline wax. These solutions actually use a mixture of conventional filler dispersion and lubricant. Although the preparation is simple and the fluidity of rubber products is improved, the dispersion effect of carbon black is poor. At the same time, these low-molecular mixtures are very easy to migrate out during the rubber preparation, processing and use, especially in polar rubber applications, which seriously affects the use and appearance of rubber products. In addition, conventional fatty acid soaps or surfactants are reactive with other additives such as vulcanizers, vulcanization accelerators, and scorch retardants. If they are used improperly, they are easy to cause scorch, prolong the vulcanization time, etc., thereby causing the mechanical properties of rubber products to decline. Therefore, this type of dispersant has the disadvantages of being inconvenient to use and having low mechanical strength. Summary of the invention

[0003] The purpose of the present invention is to provide a synthesis method and application of a special dispersant for polar rubber carbon black to solve the following technical problems: Existing dispersants have the disadvantages of being inconvenient to use and having low mechanical strength.

[0004] The purpose of the present invention can be achieved through the following technical solutions: A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In an inert protective gas atmosphere, add polyetheramine and anhydrous ethanol into reaction bottle A, add acrylate monomer, control the reaction temperature to 10-50°C, keep the reaction for 5-10 hours, and extract under vacuum to obtain intermediate I; S2: In an inert protective gas atmosphere, add intermediate I, catalyst 1, and fatty diacid into reaction flask B, control the reaction temperature to 165-185°C, and keep the reaction for 3-5 hours to obtain intermediate II; S3: In an inert protective gas atmosphere, add intermediate II, catalyst II and fatty acid into reaction bottle C, control the temperature at 190-220°C, keep the reaction warm for 5-7h under stirring conditions, cool and crush to obtain a special dispersant for polar rubber carbon black.

[0005] As a further solution of the present invention: the specific steps of vacuum extraction in S1 are: the vacuum degree is controlled at -0.05 to -0.1 MPa, and the extraction is performed for 3-6 hours.

[0006] As a further solution of the present invention: in S1, the mass ratio of polyetheramine, anhydrous ethanol and acrylate is 30-50:30-40:10-40.

[0007] As a further solution of the present invention: the mass ratio of intermediate I, catalyst I, and fatty diacid in S2 is 65-75:0.1-0.5:15-25.

[0008] As a further embodiment of the present invention: the molecular formula of the fatty diacid is HOOC(CH2) n Fats with COOH, n≥6.

[0009] As a further solution of the present invention: the mass ratio of intermediate II, catalyst II and fatty monoacid in S3 is 45-55:0.2-0.5:45-55.

[0010] As a further embodiment of the present invention: the molecular formula of the fatty acid is CH3(CH2) n (OH) m COOH, n≥10, m=1 or 2.

[0011] As a further embodiment of the present invention: Acrylate refers to one or a mixture of any proportion of methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, hydroxymethyl acrylate and hydroxyethyl acrylate.

[0012] As a further solution of the present invention: Catalyst 1 and Catalyst 2 are both concentrated sulfuric acid.

[0013] As a further embodiment of the present invention: the chemical formula of the polyetheramine is C 3n+3 H 6n+10 O nOne or a mixture of N2.

[0014] As a further solution of the present invention: the polyetheramine is a difunctional or trifunctional polyamide, and the amine value is 200-500 mgKOH / g.

[0015] The carbon black special dispersant for polar rubber synthesized by any of the above-mentioned synthesis methods is used in the field of preparation of nitrile rubber compositions.

[0016] Beneficial effects of the present invention: (1) The carbon black dispersant for polar rubber of the present invention synthesizes a type of auxiliary agent with a special branched structure through a simple and efficient chemical reaction. There are a large number of reactive groups in the dispersant prepared in the present application, such as hydroxyl (-OH) and amine (-NH2), unsaturated groups (-CH=CH-), carboxyl (-COOH), etc. During the rubber processing and use, these reactive groups can form covalent bonds with rubber or carbon black, thereby preventing the migration of the auxiliary agent. This type of auxiliary agent has a relatively high molecular weight and carries a large number of polar groups, so it has a strong interaction with polar rubber and carbon black, thereby greatly improving the dispersibility of carbon black in rubber. In addition, this type of dispersant has a special branched structure, relatively low viscosity, good heat resistance, and high end group activity, so it can not only disperse carbon black, but also improve the fluidity of rubber products and significantly improve the appearance of rubber products. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings.

[0018] Figure 1 is the Fourier infrared spectrum of the polar rubber carbon black special dispersant prepared in Example 6 of the present application; Figure 2 This is a polarizing microscope (POM) observation picture of the nitrile-based rubber products prepared in Example 6 of the present invention and Comparative Example 1. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Embodiment 1 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 300 g of polyetheramine (amine value is 200-300 mgKOH / g) and 400 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 100 g of hydroxymethyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 75 g of intermediate I, 0.1 g of catalyst 1, and 15 g of adipic acid were added to a 500 mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50 mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3 hours to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 45g of intermediate II, 0.2g of catalyst II, and 45g of 12-hydroxystearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 150mL / min, and the temperature was controlled at 190°C. The mixture was kept warm for 5h under stirring, cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0021] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 1 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0022] Embodiment 2 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 300 g of polyetheramine (amine value is 300-500 mgKOH / g) and 400 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 100 g of hydroxymethyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 75 g of intermediate I, 0.1 g of catalyst 1, and 15 g of adipic acid were added to a 500 mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50 mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3 hours to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 45g of intermediate II, 0.2g of catalyst II, and 45g of 12-hydroxystearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 150mL / min, and the temperature was controlled at 190°C. The mixture was kept warm for 5h under stirring, cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0023] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 2 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0024] Embodiment 3 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 500 g of polyetheramine (amine value of 300-500 mgKOH / g) and 400 g of anhydrous ethanol were added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask was placed in a programmed temperature-controlled oil bath, and 100 g of hydroxymethyl acrylate was added under stirring. The reaction temperature was controlled at 10°C, the reaction was kept warm for 5 h, and vacuum extraction was performed for 3 h. The vacuum degree was controlled at -0.05 MPa to obtain intermediate I. S2: In a nitrogen protective gas atmosphere, 75 g of intermediate I, 0.1 g of catalyst 1, and 15 g of adipic acid were added to a 500 mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50 mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3 hours to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 45g of intermediate II, 0.2g of catalyst II, and 45g of 12-hydroxystearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 150mL / min, and the temperature was controlled at 190°C. The mixture was kept warm for 5h under stirring, cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0025] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 3 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0026] Embodiment 4 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value is 300-500 mgKOH / g) and 300 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 400 g of hydroxymethyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65 g of intermediate I, 0.1 g of catalyst 1, and 25 g of adipic acid were added to a 500 mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50 mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3 hours to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.2g of catalyst II, and 55g of 12-hydroxystearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 150mL / min, and the temperature was controlled at 190°C. The mixture was kept warm for 5h under stirring, cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0027] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 4 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0028] Embodiment 5 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value is 300-500 mgKOH / g) and 300 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 400 g of methyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65 g of intermediate I, 0.1 g of catalyst 1, and 25 g of sebacic acid were added to a 500 mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50 mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3 hours to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.2g of catalyst II, and 55g of stearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow rate was 150mL / min, and the temperature was controlled at 190°C. The mixture was stirred for 5h and then cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0029] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 5 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0030] Example 6 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value is 300-500 mgKOH / g) and 300 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 400 g of methyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65g of intermediate I, 0.1g of catalyst 1, and 25g of dodecanedioic acid were added to a 500mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3h to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.5g of catalyst II, and 55g of 12-hydroxystearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 150mL / min, and the temperature was controlled at 190°C. The mixture was kept warm for 5h under stirring, cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0031] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 6 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0032] Embodiment 7 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value of 300-500 mgKOH / g) and 300 g of anhydrous ethanol were added into a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask was placed in a temperature-controlled oil bath, and 400 g of methyl acrylate was added under stirring. The reaction temperature was controlled at 15°C, the reaction was kept warm for 10 h, and vacuum extraction was performed for 6 h. The vacuum degree was controlled at -0.1 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65g of intermediate I, 0.1g of catalyst 1, and 25g of dodecanedioic acid were added to a 500mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50mL / min, the reaction temperature was controlled at 185°C, and the reaction was kept warm for 3h to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.5g of catalyst II, and 55g of stearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow was 250mL / min, and the temperature was controlled at 220°C. The reaction was kept warm for 7h under stirring conditions, and then cooled and crushed to obtain a special dispersant for polar rubber carbon black.

[0033] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 7 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2min, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0034] Embodiment 8 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value is 300-500 mgKOH / g) and 300 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 400 g of methyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65g of intermediate I, 0.1g of catalyst 1, and 25g of dodecanedioic acid were added to a 500mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3h to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.5g of catalyst II, and 55g of stearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow rate was 150mL / min, and the temperature was controlled at 190°C. The mixture was stirred for 5h and then cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0035] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 8 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Place the film into a mold and vulcanize it on a flat vulcanizer at a vulcanization temperature of 150°C, a pre-pressing pressure of 5 MPa, a time of 2 min, exhaust twice, a boost pressure of 15 MPa, and a time of t90+30 s to obtain a finished nitrile rubber product.

[0036] Embodiment 9 A method for synthesizing a special dispersant for polar rubber carbon black comprises the following steps: S1: In a nitrogen protective gas atmosphere, 400 g of polyetheramine (amine value is 300-500 mgKOH / g) and 300 g of anhydrous ethanol are added to a 2000 mL four-necked flask equipped with a stirrer, a thermometer, a condenser and an isobaric funnel. The four-necked flask is placed in a programmed temperature-controlled oil bath, and 400 g of methyl acrylate is added under stirring. The reaction temperature is controlled at 10°C, the reaction is kept warm for 5 hours, and vacuum extraction is performed for 3 hours. The vacuum degree is controlled at -0.05 MPa to obtain intermediate I; S2: In a nitrogen protective gas atmosphere, 65g of intermediate I, 0.1g of catalyst 1, and 25g of dodecanedioic acid were added to a 500mL three-necked flask with a stirrer and a thermometer. Under stirring, the nitrogen flow rate was 50mL / min, the reaction temperature was controlled at 165°C, and the reaction was kept warm for 3h to obtain intermediate II; S3: In a nitrogen protective gas atmosphere, 55g of intermediate II, 0.5g of catalyst II, and 55g of stearic acid were added into a 500mL three-necked flask with a stirrer and a thermometer. The nitrogen flow rate was 150mL / min, and the temperature was controlled at 190°C. The mixture was stirred for 5h and then cooled and crushed to obtain a special dispersant for carbon black for polar rubber.

[0037] The method for preparing the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, and then 25g of carbon black (brand N330), 1g of stearic acid (Indonesia 1801), 5g of zinc oxide and 2g of sulfur (S-80) were added in sequence, and then 25g of carbon black and 1g of the carbon black special dispersant for polar rubber prepared in Example 9 were added, and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle for 10 times and rolled into a film to obtain a film; A2: Place the film into a mold and vulcanize it on a flat vulcanizer at a vulcanization temperature of 150°C, a pre-pressing pressure of 5 MPa, a time of 2 min, exhaust twice, a boost pressure of 15 MPa, and a time of t90+30 s to obtain a finished nitrile rubber product.

[0038] Comparative Example 1 The preparation method of the nitrile-based rubber finished product comprises the following steps: A1: 100g of nitrile rubber (NBR 4155) was plasticated on an open mill and rolled several times, then 25g of carbon black (grade N330) was added, followed by 1g of stearic acid (Indonesia 1801), 5g of zinc oxide (commercially available industrial product) and 2g of sulfur (S-80), then 25g of carbon black and 1g of ethylene bis stearamide EBS (commercially available industrial product), and finally 1.6g of accelerator DM and 0.6g of TMTD were added, and the mixture was rolled into a triangle shape about 10 times and rolled into a film to obtain a film; A2: Put the film into the mold and vulcanize it on a flat vulcanizer. The vulcanization temperature is 150℃, the pre-pressing pressure is 5MPa, the time is 2 minutes, and the exhaust is twice. The boost pressure is 15MPa and the time is t 90 + 30s to obtain the nitrile rubber product.

[0039] Performance Testing (1) Tensile properties of rubber products: tested according to GB / T 528-2009, using dumbbell-shaped specimens. The test results are shown in Table 1. (2) Tear properties of rubber products: tested according to GB / T 529-2008, using right-angle specimens. The test results are shown in Table 1. Table 1: Rubber mechanical properties test data statistics

[0040] As can be seen from Table 1, the nitrile rubber product added with the special dispersant for carbon black for polar rubber prepared in the present application has excellent mechanical properties (tensile strength, tear strength, elongation at break, 100% tensile stress, 300% tensile stress), which is significantly improved than the mechanical properties of the vulcanized nitrile rubber added with bis(stearic acid amide) EBS. The special dispersant for carbon black for polar rubber prepared in the present application has a significant dispersing effect on carbon black.

[0041] See also Figure 1 Take the carbon black dispersant for polar rubber prepared in Example 6, melt it and make it into a 1-2 mm thick sheet, and use Fourier infrared spectroscopy (using reflection method) to obtain its infrared spectrum. Figure 1 It can be seen that the carbon black dispersant for polar rubber prepared in Example 6 has certain active groups such as hydroxyl (-OH), carboxyl (-COOH), amine (-NH), and polar groups such as ester (-COO) and amide (-CONH-). These active groups can form covalent bonds with rubber or carbon black, thereby preventing the migration of the additive. The polar groups on the molecule have a strong interaction with polar rubber and carbon black, thereby greatly improving the dispersibility of carbon black in rubber.

[0042] See also Figure 2 The nitrile rubber products prepared in Example 6 and Comparative Example 1 were then observed using a polarizing microscope (POM) to determine the dispersion of carbon black in the rubber. Figure 2 (a) is the observation diagram of comparative example 1, Figure 2 (b) is an observation diagram of Example 6. Figure 2 It can be seen that in the vulcanized nitrile rubber with ethylene bis stearamide EBS as a dispersant, the carbon black is in a state of large particle agglomeration, while in the vulcanized nitrile rubber with the carbon black special dispersant for polar rubber prepared in Example 6, the carbon black is obviously dispersed evenly and the agglomeration phenomenon is significantly reduced.

[0043] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for synthesizing a special dispersant for polar rubber carbon black, characterized in that: The steps include: S1: In an inert protective gas atmosphere, add polyetheramine and anhydrous ethanol into reaction bottle A, add acrylate monomer, control the reaction temperature to 10-50°C, keep the reaction for 5-10 hours, and extract under vacuum to obtain intermediate I; S2: In an inert protective gas atmosphere, add intermediate I, catalyst 1, and fatty diacid into reaction flask B, control the reaction temperature to 165-185°C, and keep the reaction for 3-5 hours to obtain intermediate II; S3: In an inert protective gas atmosphere, add intermediate II, catalyst II and fatty acid into reaction bottle C, control the temperature at 190-220°C, keep the reaction warm for 5-7h under stirring conditions, cool and crush to obtain a special dispersant for polar rubber carbon black.

2. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The mass ratio of polyetheramine, anhydrous ethanol and acrylate in S1 is 30-50:30-40:10-40.

3. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The mass ratio of intermediate I, catalyst I, and fatty diacid in S2 is 65-75:0.1-0.5:15-25.

4. The method for synthesizing a special carbon black dispersant for polar rubber according to claim 1, characterized in that: The molecular formula of the fatty diacid is HOOC(CH2) n Fats with COOH, n≥6.

5. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The mass ratio of intermediate II, catalyst II and fatty acid in S3 is 45-55:0.2-0.5:45-55.

6. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The molecular formula of the fatty acid is CH3(CH2) n (OH) m COOH, n≥10, m=1 or 2.

7. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The acrylic acid ester refers to one of methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, hydroxymethyl acrylate, and hydroxyethyl acrylate, or a mixture of any of the above.

8. The method for synthesizing a special dispersant for polar rubber carbon black according to claim 1, characterized in that: The catalyst one and the catalyst two are both concentrated sulfuric acid.

9. The carbon black special dispersant for polar rubber synthesized by the synthesis method according to any one of claims 1 to 9 is used in the field of preparing nitrile rubber compositions.

Images