Method for producing polyacrylamide by kneading machine

Abstract

The invention discloses a method for producing polyacrylamide by a kneading machine. The method comprises the following steps: (1) forming a mixed solution A from acrylamide, 2-acrylamido-2-methyl propane sodium sulfonate, polyethylene glycol diacrylamide, a chain transfer auxiliary agent and water; (2) forming a cationic monomer solution from a cationic monomer, a cosolvent and water; (3) forming a mixed solution B from a part of the mixed solution A and a part of the cation mixed solution; (4) forming a mixed solution C from a redox initiator, an azo initiator and water; (5) putting the residual mixed solution A into a polymerization reaction kettle, introducing nitrogen to remove oxygen, regulating the temperature, adding the mixed solution C, stirring to react, cooling, adding the cationic monomer solution and the mixed solution C, stirring to react, cooling, adding the mixed solution B and the mixed solution C, stirring to react, heating, preserving heat and standing to obtain colloid; and (6) transferring the colloid into a kneading machine, vacuumizing and kneading. The produced polyacrylamide is high in molecular weight and concentrated in distribution, and has good dissolution and flocculation performance.

Description

Technical Field

[0001] The invention relates to a method for producing polyacrylamide with a kneader, belonging to the technical field of polyacrylamide. Background Art

[0002] Polyacrylamide (PAM) is a linear high molecular polymer with excellent physical and chemical properties such as flocculation and sedimentation, purification, drag reduction or thickening. It is the most important variety of water-soluble high molecular weight polyelectrolytes and is widely used in oil field development, mining, printing and dyeing, water treatment and soil improvement. The molecular weight of polyacrylamide is relatively high. The molecular weight of commonly used polyacrylamide is generally in the millions to tens of millions. The higher the molecular weight of polyacrylamide, the stronger its flocculation and adsorption capacity. However, the higher the molecular weight of polyacrylamide, the slower its dissolution rate in water, and even leads to uneven dissolution. Summary of the invention

[0003] In order to solve at least one problem existing in the above-mentioned prior art, the present invention provides a method for producing polyacrylamide using a kneader, which can obtain polyacrylamide with a high molecular weight of 10 to 12 million and a relatively concentrated molecular weight distribution; and the polyacrylamide has good solubility and flocculation properties.

[0004] In order to achieve the above object, the present invention adopts the following technical scheme: a method for producing polyacrylamide by a kneading machine, comprising the following steps:

[0005] (1) acrylamide, 2-acrylamido-2-methylpropane sulfonic acid sodium salt, polyethylene glycol diacrylamide, a chain transfer auxiliary agent and a portion of water are stirred and mixed to obtain a mixed solution A;

[0006] (2) stirring and mixing the cationic monomer, the co-solvent and a portion of water to obtain a cationic monomer solution;

[0007] (3) stirring and mixing the mixed solution A accounting for 20% of the total mass and the cationic mixed solution accounting for 30% of the total mass to obtain a mixed solution B;

[0008] (4) stirring and mixing the redox initiator, the azo initiator and the remaining water to obtain a mixed solution C;

[0009] (5) adding the remaining mixed solution A to the polymerization reactor, continuously introducing nitrogen to deoxygenate, adjusting the temperature to 18-20° C., adding 40% of the total mass of mixed solution C, and stirring at 800-850 rpm for reaction for 10-15 min; then cooling to 10-12° C., adding the remaining cationic monomer solution and 45% of the total mass of mixed solution C, and stirring at 550-600 rpm for reaction for 20-25 min; then cooling to 6-8° C., adding mixed solution B and the remaining mixed solution C, and stirring at 200-250 rpm for reaction for 25-30 min; then stirring at 100-150 rpm and heating to 60-65° C. at a rate of 2° C. / min, and then keeping the temperature for 1-1.5 h to obtain a colloid;

[0010] (6) The colloid is transferred to a kneader and evacuated, first kneaded to a colloid temperature of 40-45° C., then kneaded to a colloid water content of 28-32%, and finally kneaded into flakes, which are then dried and ground to obtain a powdery polyacrylamide with a high molecular weight of 10 to 12 million.

[0011] Preferably, in the production method of polyacrylamide, the mass ratio of acrylamide, 2-acrylamido-2-methylpropane sulfonic acid sodium salt, cationic monomer and water is 3-4:1:1:8-10;

[0012] The amount of water added to the mixed solution A is 60-65% of the total weight of water; the amount of water added to the mixed solution B is 25-30% of the total weight of water; the amount of water added to the mixed solution C is the amount of remaining water.

[0013] Preferably, the cationic monomer is a combination of methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride and dimethyl diallyl ammonium chloride.

[0014] Preferably, one of the methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride is combined with dimethyl diallyl ammonium chloride in a mass ratio of 3 to 4:1.

[0015] Preferably, the added amount of the hydroxy polyethylene glycol acrylamide is 10-15% of the mass of acrylamide.

[0016] Preferably, the molecular weight of the polyethylene glycol in the hydroxy polyethylene glycol diacrylamide is 1000 or 1500.

[0017] Preferably, the added amount of the chain transfer auxiliary agent is 0.25-0.31% of the mass of acrylamide.

[0018] Preferably, the transfer aid is one of sodium formate or potassium formate.

[0019] Preferably, the amount of the co-solvent added is 0.6-0.8% of the mass of acrylamide.

[0020] Preferably, the co-solvent is one of sodium benzoate or sodium p-aminobenzoate.

[0021] Preferably, the added amount of the redox initiator is 0.06-0.07% of the mass of acrylamide.

[0022] Preferably, the redox initiator is composed of ammonium persulfate and sodium bisulfite.

[0023] Preferably, the mass ratio of ammonium persulfate to sodium bisulfite is 2 to 2.5:1.

[0024] Preferably, the added amount of the azo initiator is 0.33-0.4% of the mass of acrylamide.

[0025] Preferably, the azo initiator is azobisisobutyronitrile or azobispentylbutyronitrile.

[0026] The invention has the beneficial effects that the molecular weight of the polyacrylamide produced by the invention is concentrated in the range of 10 to 12 million, the molecular weight of the polyacrylamide is high and the distribution is relatively uniform, the dissolution rate of the polyacrylamide is fast, the flocculation effect is good, and the polyacrylamide has good dissolution and flocculation performances. In the method for producing polyacrylamide of the invention, 2-acrylamide-2-methylpropane sulfonic acid sodium salt and hydroxy polyethylene glycol acrylamide are added to polymerize acrylamide, and the 2-acrylamide-2-methylpropane sulfonic acid sodium salt and hydroxy polyethylene glycol acrylamide cooperate with the polyacrylamide to accelerate the dissolution rate and enhance the flocculation effect. In the method for producing polyacrylamide of the invention, a cationic monomer which is a combination of dimethyl diallyl ammonium chloride and methacryloyloxyethyl dimethyl benzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride is used, which is more helpful to improve the dissolution and flocculation performances of the polyacrylamide. The polymerization process in the method for producing polyacrylamide of the invention is more excellent for producing high molecular weight polyacrylamide. DETAILED DESCRIPTION

[0027] The following is a clear and complete description of the technical solutions in the implementation of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. If the specific conditions are not specified in the embodiments, they are carried out according to the normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents, instruments, and components used, they are all conventional products that can be purchased commercially.

[0028] Example 1

[0029] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0030] S1, raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3g hydroxy polyethylene glycol diacrylamide with a polyethylene glycol molecular weight of 1000, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 9.575g of the mixed solution A and 3.654g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g of azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0031] S2, polymerization reaction: 38.3g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.526g of cationic monomer solution and 0.593g of mixed solution C were added and stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the above mixed solution B and 0.198g of mixed solution C were added and stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0032] S3, kneading: the colloid is transferred to a kneading machine and evacuated, first kneaded to the colloid temperature of 40 ° C, then kneaded to the colloid water content of 32%, and finally kneaded into sheets, and then dried and ground to obtain a powder of high molecular weight polyacrylamide of 10 to 12 million.

[0033] Example 2

[0034] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0035] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3.5g hydroxy polyethylene glycol diacrylamide with a polyethylene glycol molecular weight of 1000, 0.0875g sodium formate and 5.4g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.21g sodium benzoate and 2.25g water were stirred and mixed to obtain a cationic monomer solution; 3) 10.7975g of the mixed solution A and 3.738g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.021g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.116g of azobisisobutyronitrile and 1.35g water were stirred and mixed to obtain a mixed solution C;

[0036] S2, polymerization reaction: 43.19g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.595g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 8.722g of cationic monomer solution and 0.669g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.223g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0037] S3, kneading: the colloid is transferred to a kneading machine and evacuated, first kneaded to the colloid temperature of 43 ° C, then kneaded to the colloid water content of 30%, and finally kneaded into sheets, and then dried and ground to obtain a powder of high molecular weight polyacrylamide of 10 to 12 million.

[0038] Example 3

[0039] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0040] S1, raw material processing: 1) 40g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.1g sodium formate and 6g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.24g sodium benzoate and 2.5g water were stirred and mixed to obtain a cationic monomer solution; 3) 12.02g of the mixed solution A and 3.822g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.024g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.132g of azobisisobutyronitrile and 1.5g water were stirred and mixed to obtain a mixed solution C;

[0041] S2, polymerization reaction: 48.08g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 20°C, 0.662g of mixed solution C was added and stirred at 850rpm for 10min; then the temperature was lowered to 12°C, 8.918g of cationic monomer solution and 0.745g of mixed solution C were added and stirred at 600rpm for 25min; then the temperature was lowered to 8°C, the mixed solution B and 0.248g of mixed solution C were added and stirred at 250rpm for 25min; then the temperature was stirred at 150rpm and the temperature was raised to 65°C at a rate of 2°C / min, and then the temperature was kept and allowed to stand for 1h to obtain a colloid;

[0042] S3, kneading: the colloid is transferred to a kneading machine and evacuated, first kneaded to the colloid temperature of 45 ° C, then kneaded to the colloid water content of 28%, and finally kneaded into sheets, and then dried and ground to obtain a powder of high molecular weight polyacrylamide of 10 to 12 million.

[0043] Example 4

[0044] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0045] S1, raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3.6g hydroxy polyethylene glycol diacrylamide with a polyethylene glycol molecular weight of 1000, 0.084g sodium formate and 5g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.21g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 9.7368g of the mixed solution A and 3.723g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.02g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.108g of azobisisobutyronitrile and 0.8g water were stirred and mixed to obtain a mixed solution C;

[0046] S2, polymerization reaction: 38.9472g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.371g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.687g of cationic monomer solution and 0.417g of mixed solution C were added and stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the above mixed solution B and 0.139g of mixed solution C were added and stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0047] Step S3 of Example 4 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0048] Example 5

[0049] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0050] S1, raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.5g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.093g sodium formate and 5.2g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.24g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 9.9586g of the mixed solution A and 3.792g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.021g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.12g of azobisisobutyronitrile and 0.4g water were stirred and mixed to obtain a mixed solution C;

[0051] S2, polymerization reaction: 39.8344g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.216g of mixed solution C was added, and the mixture was stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.848g of cationic monomer solution and 0.243g of mixed solution C were added, and the mixture was stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the above mixed solution B and 0.081g of mixed solution C were added, and the mixture was stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0052] Step S3 of Example 5 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0053] Example 6

[0054] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0055] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.2g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.098g sodium formate and 6.25g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3.5:1, 0.245g sodium benzoate and 2.75g water were stirred and mixed to obtain a cationic monomer solution; 3) 10.9846g of the mixed solution A and 3.816g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.023g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2.25:1, 0.126g of azobisisobutyronitrile and 1g water were stirred and mixed to obtain a mixed solution C;

[0056] S2, polymerization reaction: 43.9384g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.42g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 8.904g of cationic monomer solution and 0.472g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.157g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0057] Step S3 of Example 6 is exactly the same as Step S3 of Example 2, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0058] Example 7

[0059] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0060] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.2g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.098g sodium formate and 6.25g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 4:1, 0.245g sodium aminobenzoate and 2.75g water were stirred and mixed to obtain a cationic monomer solution; 3) 11.1096g of the mixed solution A and 3.8985g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.023g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2.5:1, 0.126g of azobisisobutyronitrile and 1g water were stirred and mixed to obtain a mixed solution C;

[0061] S2, polymerization reaction: 44.4384g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.46g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 9.0965g of cationic monomer solution and 0.517g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.172g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0062] Step S3 of Example 7 is exactly the same as Step S3 of Example 2, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0063] Example 8

[0064] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0065] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.2g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1500, 0.098g potassium formate and 5.625g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3.5:1, 0.245g of sodium aminobenzoate and 2.475g of water were stirred and mixed to obtain a cationic monomer solution; 3) 10.9846g of the mixed solution A and 3.8985g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.023g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2.5:1, 0.126g of azobisisovaleronitrile and 0.9g of water were stirred and mixed to obtain a mixed solution C;

[0066] S2, polymerization reaction: 43.9384g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.46g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 8.904g of cationic monomer solution and 0.472g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.157g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0067] Step S3 of Example 8 is exactly the same as Step S3 of Example 2, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0068] Example 9

[0069] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0070] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.2g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.098g potassium formate and 6.25g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of acryloyloxyethyl trimethyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 4:1, 0.245g of sodium aminobenzoate and 2.75g of water were stirred and mixed to obtain a cationic monomer solution; 3) 11.1096g of the mixed solution A and 3.8985g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.023g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2.25:1, 0.126g of azobisisovaleronitrile and 1g of water were stirred and mixed to obtain a mixed solution C;

[0071] S2, polymerization reaction: 44.4384g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.46g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 9.0965g of cationic monomer solution and 0.517g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.172g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0072] Step S3 of Example 9 is exactly the same as Step S3 of Example 2, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0073] Example 10

[0074] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0075] S1, raw material processing: 1) 35g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 4.2g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.098g potassium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of acryloyloxyethyl trimethyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3.5:1, 0.245g of sodium aminobenzoate and 2g of water were stirred and mixed to obtain a cationic monomer solution; 3) 10.8196g of the mixed solution A and 3.6735g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.023g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.126g of azobisisobutyronitrile and 1.2g of water were stirred and mixed to obtain a mixed solution C;

[0076] S2, polymerization reaction: 43.2784g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 19°C, 0.54g of mixed solution C was added and stirred at 825rpm for 12min; then the temperature was lowered to 11°C, 8.5715g of cationic monomer solution and 0.607g of mixed solution C were added and stirred at 575rpm for 25min; then the temperature was lowered to 7°C, the mixed solution B and 0.202g of mixed solution C were added and stirred at 225rpm for 28min; then the mixture was stirred at 125rpm and heated to 62°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.25h to obtain a colloid;

[0077] Step S3 of Example 10 is exactly the same as Step S3 of Example 2, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0078] Comparative Example 1

[0079] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0080] S1, raw material processing: 1) 30g acrylamide, 3g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 7.575g of the mixed solution A and 3.654g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g of azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0081] S2, polymerization reaction: 30.3g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added, and the mixture was stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.526g of cationic monomer solution and 0.593g of mixed solution C were added, and the mixture was stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the mixed solution B and 0.198g of mixed solution C were added, and the mixture was stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0082] Step S3 of Comparative Example 1 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0083] Comparative Example 2

[0084] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0085] S1, raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 8.5975g of the mixed solution A and 3.654g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0086] S2, polymerization reaction: 35.9g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.526g of cationic monomer solution and 0.593g of mixed solution C were added and stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the above mixed solution B and 0.198g of mixed solution C were added and stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0087] Step S3 of Comparative Example 2 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0088] Comparative Example 3

[0089] A method for producing polyacrylamide with a kneader comprises the following steps: steps S2 and S3 of comparative example 2 are completely identical to steps S2 and S3 of embodiment 1, and step S1 of comparative example 2 is partially identical to step S1 of embodiment 1, except that: only methacryloyloxyethyl dimethylbenzyl ammonium chloride is selected as the cationic monomer.

[0090] Comparative Example 4

[0091] A method for producing polyacrylamide by a kneading machine comprises the following steps: steps S2 and S3 of comparative example 2 are completely identical to steps S2 and S3 of embodiment 1, and step S1 of comparative example 2 is partially identical to step S1 of embodiment 1, except that: methacryloyloxyethyl dimethylbenzyl ammonium chloride is selected as the cationic monomer; and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0092] Comparative Example 4

[0093] A method for producing polyacrylamide with a kneader comprises the following steps: steps S2 and S3 of comparative example 2 are completely identical to steps S2 and S3 of embodiment 1, and step S1 of comparative example 2 is partially identical to step S1 of embodiment 1, except that only dimethyldiallylammonium chloride is selected as the cationic monomer; and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0094] Comparative Example 5

[0095] A method for producing polyacrylamide by a kneading machine comprises the following steps: steps S2 and S3 of comparative example 2 are completely identical to steps S2 and S3 of embodiment 1, and step S1 of comparative example 2 is partially identical to step S1 of embodiment 1, except that the cationic monomer is composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 1:1; and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0096] Comparative Example 6

[0097] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0098] Raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 8.975g of the mixed solution A and 3.654g of the cationic monomer solution were stirred and mixed to obtain a mixed solution B; 4) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g of azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0099] S2, polymerization reaction: 35.9g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 8.526g of cationic monomer solution and 0.593g of mixed solution C were added and stirred at 550rpm for 25min; then the temperature was lowered to 6°C, the above mixed solution B and 0.198g of mixed solution C were added and stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the mixture was kept warm and allowed to stand for 1.5h to obtain a colloid;

[0100] S3, kneading: transfer the colloid to a kneader and add 3g of polyethylene glycol with a molecular weight of 1000, then evacuate, first knead until the colloid temperature is 40°C, then knead until the colloid water content is 32%, then knead into sheets, and then dry and grind to obtain powdered polyacrylamide with a high molecular weight of 10 to 12 million.

[0101] Comparative Example 7

[0102] A method for producing polyacrylamide with a kneader, comprising the following steps: Step S3 of Comparative Example 6 is completely the same as Step S3 of Example 1;

[0103] S1, raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3g hydroxy polyethylene glycol diacrylamide with a polyethylene glycol molecular weight of 1000, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0104] S2, polymerization reaction: 47.875g of mixed solution A was added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 12.18g of cationic monomer solution and 0.593g of mixed solution C were added and stirred at 550rpm for 25min, then the temperature was lowered to 6°C, 0.198g of mixed solution C was added and stirred at 200rpm for 30min; then the mixture was stirred at 100rpm and heated to 60°C at a rate of 2°C / min, and then kept warm for 2 to obtain a colloid;

[0105] Step S3 of Comparative Example 7 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0106] Comparative Example 8

[0107] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0108] Raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0109] S2, polymerization reaction: 47.875g of mixed solution A and 12.18g of cationic monomer solution were added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for 15min; then the temperature was lowered to 10°C, 0.593g of mixed solution C was added and stirred at 550rpm for 25min; then the temperature was lowered to 6°C, 0.198g of mixed solution C was added and stirred at 200rpm for 30min; then the temperature was stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then the temperature was kept and allowed to stand for 1.5h to obtain a colloid;

[0110] Step S3 of Comparative Example 8 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0111] Comparative Example 9

[0112] A method for producing polyacrylamide with a kneader comprises the following steps: Steps S1 and S3 of Comparative Example 9 are completely the same as Steps S1 and S3 of Example 1, and are different from Step S2 of Example 1 in that: Step S2 of Comparative Example 9, polymerization reaction: 38.3 g of mixed solution A is added to a polymerization reaction kettle, nitrogen is continuously introduced for deoxygenation, the temperature is adjusted to 18° C., 0.527 g of mixed solution C is added, and the mixture is stirred at 800 rpm for reaction for 15 min; then the mixture is kept warm, 8.526 g of a cationic monomer solution and 0.593 g of mixed solution C are added, and the mixture is stirred at 550 rpm for reaction for 25 min; then the mixture is kept warm, the mixed solution B and 0.198 g of mixed solution C are added, and the mixture is stirred at 200 rpm for reaction for 30 min; then the mixture is stirred at 100 rpm and the temperature is raised to 60° C. at a rate of 2° C. / min, and then the mixture is kept warm and allowed to stand for 1.5 h to obtain a colloid;

[0113] A powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0114] Comparative Example 10

[0115] A method for producing polyacrylamide using a kneader, comprising the following steps:

[0116] Raw material processing: 1) 30g acrylamide, 10g 2-acrylamido-2-methylpropane sulfonic acid sodium salt, 3g hydroxy polyethylene glycol diacrylamide with a molecular weight of 1000, 0.075g sodium formate and 4.8g water were stirred and mixed to obtain a mixed solution A; 2) 10g of a cationic monomer composed of methacryloyloxyethyl dimethylbenzyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3:1, 0.18g sodium benzoate and 2g water were stirred and mixed to obtain a cationic monomer solution; 3) 0.018g of a redox initiator composed of ammonium persulfate and sodium bisulfite in a mass ratio of 2:1, 0.099g azobisisobutyronitrile and 1.2g water were stirred and mixed to obtain a mixed solution C;

[0117] S2, polymerization reaction: 47.875g of mixed solution A and 12.18g of cationic monomer solution were added to a polymerization reaction kettle, nitrogen was continuously introduced for deoxygenation, the temperature was adjusted to 18°C, 0.527g of mixed solution C was added and stirred at 800rpm for reaction for 50min; then stirred at 100rpm and the temperature was raised to 60°C at a rate of 2°C / min, and then kept warm and allowed to stand for 1.5h to obtain a colloid;

[0118] Step S3 of Comparative Example 10 is exactly the same as Step S3 of Example 1, and a powdery polyacrylamide with a high molecular weight of 10 to 12 million is obtained.

[0119] Comparative Example 11

[0120] A method for producing polyacrylamide with a kneader comprises the following steps: step S1 of comparative example 11 is completely the same as step S1 of embodiment 1, and steps S2 and S3 of comparative example 11 are partially the same as steps S2 and S3 of embodiment 1, except that: S2, polymerization reaction: 38.3 g of mixed solution A is added into a polymerization reaction kettle, nitrogen is continuously introduced for deoxygenation, the temperature is adjusted to 18° C., 0.527 g of mixed solution C is added, and the mixture is stirred at 800 rpm for reaction for 15 min; then the temperature is lowered to 10° C., 8.526 g of cationic monomer solution and 0.593 g of mixed solution C are added, and the mixture is stirred at 550 rpm for reaction for 25 min; then the temperature is lowered to 6° C., the mixed solution B and 0.198 g of mixed solution C are added, the mixture is stirred at 200 rpm for reaction for 30 min, and then the mixture is allowed to stand for reaction for 2 h to obtain a colloid;

[0121] S3, kneading: the colloid is transferred to a kneading machine at 60°C and vacuumed for 1 hour, then kneaded to the colloid temperature of 40°C, then kneaded to the colloid water content of 32%, and finally kneaded into sheets, and then dried and ground to obtain a powdery polyacrylamide with a high molecular weight of 10 to 12 million.

[0122] 1. The molecular weight, residual monomer rate and dissolution rate of the polyacrylamide produced in Examples 1 to 10 and Comparative Examples 1 to 10 were measured according to GB / T31246-2014.

[0123] 2. The polyacrylamide produced in Examples 1 to 10 and Comparative Examples 1 to 10 was used to treat industrial wastewater. The COD content of the wastewater before treatment was 512 (mg / L). 1L of wastewater was taken as 1 portion, and the sample amount added to each 1L of wastewater was 25 mg. The COD changes before and after the wastewater treatment were measured, and the results are shown in Table 1.

[0124]

[0125]

[0126] It can be seen from Table 1 above that the molecular weights of the polyacrylamide prepared in Examples 1 to 3 of the present invention are concentrated in the range of 10 to 12 million, the molecular weight of the polyacrylamide is high and the distribution is relatively uniform, and the dissolution rate of the polyacrylamide is fast and has good flocculation performance.

[0127] Compared with Example 1, in Comparative Example 1, no 2-acrylamide-2-methylpropane sulfonic acid sodium salt was added, and in Comparative Example 2, no hydroxypolyethylene glycol acrylamide was added. The dissolution rate of polyacrylamide was greatly slowed down and the flocculation performance was greatly reduced, indicating that 2-acrylamide-2-methylpropane sulfonic acid sodium salt and hydroxypolyethylene glycol acrylamide synergistically can improve the solubility and flocculation performance of polyacrylamide.

[0128] Compared with Example 1, in Comparative Example 3, the cationic monomer is methacryloyloxyethyl dimethylbenzyl ammonium chloride, in Comparative Example 4, the cationic monomer is acryloyloxyethyl trimethyl ammonium chloride, and in Comparative Example 5, the cationic monomer consists of methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride in a mass ratio of 2:1. The dissolution time of polyacrylamide is prolonged to be greater than 10 min, and the COD removal rate of polyacrylamide for sewage is reduced to be less than 89%, indicating that a cationic monomer of a combination of dimethyldiallyl ammonium chloride and methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride helps to improve the solubility and flocculation properties of polyacrylamide.

[0129] Compared with Example 1 and Comparative Example 2, in Comparative Example 6, hydroxypolyethylene glycol acrylamide was not added and polyethylene glycol was added during kneading, indicating that when the polyacrylamide colloid and polyethylene glycol are compounded, although polyethylene glycol can accelerate the dissolution rate of polyacrylamide, the time for polyacrylamide is still relatively long, and the flocculation effect of polyacrylamide is deteriorated.

[0130] Compared with Example 1, in Comparative Example 7, the entire mixed solution A is first partially reacted, then cooled, and the entire cationic monomer solution is added, reacted, and then heated and kept still; in Comparative Example 8, the entire mixed solution A and the entire cationic monomer solution are mixed, then cooled in sequence, reacted, and then heated and kept still; in Comparative Example 9, materials are added in sequence at 18°C ​​for reaction, then heated and kept still; in Comparative Example 10, the entire mixed solution A and the entire cationic monomer solution are mixed, reacted at 18°C, then heated and kept still; in Comparative Example 11, after cooling and reacting, the mixture is directly kept still without heating, and then directly placed at 60°C for vacuum insulation. The molecular weight of the polyolefin amides in Comparative Examples 7 to 11 is between 6.5 million and 9.5 million, less than 10 million, and the residual monomer content is also relatively high. Although the polyolefin amide has good solubility, the COD removal rate is less than 80%, and the flocculation performance is poor.

[0131] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit and essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0132] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for producing polyacrylamide using a kneader, characterized in that: The following steps are involved: (1) acrylamide, 2-acrylamido-2-methylpropane sulfonic acid sodium salt, polyethylene glycol diacrylamide, a chain transfer auxiliary agent and a portion of water are stirred and mixed to obtain a mixed solution A; (2) stirring and mixing the cationic monomer, the co-solvent and a portion of water to obtain a cationic monomer solution; (3) stirring and mixing the mixed solution A accounting for 20% of the total mass and the cationic mixed solution accounting for 30% of the total mass to obtain a mixed solution B; (4) stirring and mixing the redox initiator, the azo initiator and the remaining water to obtain a mixed solution C; (5) adding the remaining mixed solution A to the polymerization reactor, continuously introducing nitrogen to deoxygenate, adjusting the temperature to 18-20° C., adding 40% of the total mass of mixed solution C, and stirring at 800-850 rpm for reaction for 10-15 min; then cooling to 10-12° C., adding the remaining cationic monomer solution and 45% of the total mass of mixed solution C, and stirring at 550-600 rpm for reaction for 20-25 min; then cooling to 6-8° C., adding mixed solution B and the remaining mixed solution C, and stirring at 200-250 rpm for reaction for 25-30 min; then stirring at 100-150 rpm and heating to 60-65° C. at a rate of 2° C. / min, and then keeping the temperature for 1-1.5 h to obtain a colloid; (6) The colloid is transferred to a kneader and evacuated, first kneaded to a colloid temperature of 40-45° C., then kneaded to a colloid water content of 28-32%, and finally kneaded into flakes, which are then dried and ground to obtain a powdery polyacrylamide with a high molecular weight of 10 to 12 million.

2. The method for producing polyacrylamide using a kneader according to claim 1, characterized in that: In the production method of polyacrylamide, the mass ratio of acrylamide, 2-acrylamido-2-methylpropane sulfonic acid sodium salt, cationic monomer and water is 3-4:1:1:8-10; The amount of water added to the mixed solution A is 60-65% of the total weight of water; the amount of water added to the mixed solution B is 25-30% of the total weight of water; the amount of water added to the mixed solution C is the amount of remaining water.

3. The method for producing polyacrylamide using a kneader according to claim 1 or 2, characterized in that: The cationic monomer is a combination of methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride and dimethyl diallyl ammonium chloride.

4. The method for producing polyacrylamide using a kneader according to claim 3, wherein the cationic monomer is a combination of methacryloyloxyethyl dimethylbenzyl ammonium chloride or acryloyloxyethyl trimethyl ammonium chloride and dimethyl diallyl ammonium chloride in a mass ratio of 3 to 4:

1.

5. The method for producing polyacrylamide using a kneader according to claim 2, characterized in that: The added amount of the chain transfer auxiliary agent is 0.25-0.31% of the mass of acrylamide.

6. The method for producing polyacrylamide using a kneader according to claim 1 or 2, characterized in that: The addition amount of the hydroxy polyethylene glycol acrylamide is 10-15% of the mass of acrylamide; the polyethylene glycol in the hydroxy polyethylene glycol diacrylamide is one with a molecular weight of 1000 or a molecular weight of 1500.

7. The method for producing polyacrylamide using a kneader according to claim 2, characterized in that: The added amount of the co-solvent is 0.6-0.8% of the mass of acrylamide.

8. The method for producing polyacrylamide using a kneader according to claim 2, characterized in that: The added amount of the redox initiator is 0.06-0.07% of the mass of acrylamide.

9. The method for producing polyacrylamide using a kneader according to claim 2, characterized in that: The added amount of the azo initiator is 0.33-0.4% of the mass of acrylamide.

10. The method for producing polyacrylamide using a kneader according to claim 1, characterized in that: The transfer auxiliary agent is one of sodium formate or potassium formate; the cosolvent is one of sodium benzoate or sodium p-aminobenzoate; the redox initiator is a combination of ammonium persulfate and sodium bisulfite in a mass ratio of 2 to 2.5:1; the azo initiator is one of azobisisobutyronitrile or azobispentylbutyronitrile.

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