A Polyaluminum Sulfate Modified Accelerator, Its Preparation Method and Application

Abstract

This invention discloses a modified polyaluminum sulfate quick-setting agent, its preparation method, and its application. The agent comprises the following raw materials in parts by weight: 20-60 parts aluminum sulfate, 1-6 parts solid alkalizing agent, and 30-70 parts modified polyacrylamide. The preparation process of the modified polyacrylamide includes the following steps: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole is dissolved in anhydrous ethanol solution and mixed with a 0.1% (w / w) Na2CO3 aqueous solution under nitrogen protection. Then, 1,2,7,8-diepoxyoctane is added, and the reaction is carried out at 80°C for 7 hours to obtain intermediate 1. Intermediate 1 is mixed with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and reacted to obtain intermediate 2. A polyacrylamide solution is added to intermediate 2, and the reaction is carried out to obtain modified polyacrylamide. This invention effectively improves the antioxidant and UV-resistant capabilities of the modified polyaluminum sulfate quick-setting agent, thus extending its service life.

Description

Technical Field

[0001] This invention relates to the field of quick-setting agents, specifically to a polyaluminum sulfate modified quick-setting agent, its preparation method, and its application. Background Technology

[0002] Chinese Patent CN 114804713 A discloses a method for preparing a modified polyaluminum sulfate quick-setting agent, comprising the following steps: Step 1: Gradually and slowly add an inorganic dispersant to water at room temperature, mix well, and obtain a milky white colloidal dispersion; Step 2: Dissolve sodium hydroxide in water according to the specified ratio, heat to 95°C, then add gibbsite powder to react, prepare a solution with a sodium aluminate concentration of 70%, stop heating, add cold water to cool down and keep the temperature constant at 50°C, add tetraethyl orthosilicate and ferrous sulfate under a stirring speed of 300 r / min, and continue stirring for 30 min to obtain a modified polysilicic acid solution; Step 3: Slowly add the modified polysilicic acid solution to the milky white colloidal dispersion, add sodium fluoride and an organic thickener, mix well, heat to 75°C, then add aluminum sulfate, stir evenly, and keep the reaction at this temperature for 1.5-3.0 h to obtain the modified polyaluminum sulfate quick-setting agent;

[0003] In the existing technology, the polyacrylamide organic thickener used in the modified polyaluminum sulfate quick-setting agent has the problem that the polyacrylamide is easily oxidized under high intensity ultraviolet radiation, which will greatly reduce the effect of the quick-setting agent. Summary of the Invention

[0004] The purpose of this invention is to solve the problems mentioned above in the background art, and to propose a polyaluminum sulfate modified quick-setting agent, its preparation method and application.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A polyaluminum sulfate modified quick-setting agent comprises the following raw materials in parts by weight: 20-60 parts aluminum sulfate, 1-6 parts solid alkalizing agent and 30-70 parts modified polyacrylamide;

[0007] The preparation process of modified polyacrylamide includes the following steps:

[0008] Step 1: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole was dissolved in anhydrous ethanol solution and mixed with 0.1% Na2CO3 aqueous solution under nitrogen protection. Then 1,2,7,8-diepoxyoctane was added and the reaction was carried out at 80℃ for 7 hours to obtain intermediate 1.

[0009] Step 2: Intermediate 1 is mixed with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid is added as a catalyst. The mixture is reacted for 10-20 h under a nitrogen atmosphere and at a temperature of 150 °C to obtain intermediate 2.

[0010] Step 3: Adjust the pH of a 1% polyacrylamide solution to 10 with a 10% sodium hydroxide solution, then add intermediate 2 and react at 45-60℃ for 1-3 hours to obtain modified polyacrylamide.

[0011] As a further aspect of the present invention: the ratio of the aqueous solution of 2-(2,4-dihydroxyphenyl)-2H-benzotriazole, 1,2,7,8-diepoxyoctane, and 0.1% Na2CO3 is controlled to be 1-1.2 mol: 1-1.2 mol: 1000-1800 mL.

[0012] As a further aspect of the present invention: the ratio of intermediate 1, (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid is controlled to be 1-1.2 mol: 1-1.2 mol: 0.01 mol.

[0013] As a further aspect of the present invention: the ratio of polyacrylamide to intermediate 2 is controlled to be 1-1.2 mol: 0.4-0.6 mol.

[0014] A method for preparing a polyaluminum sulfate modified quick-setting agent involves adding a solid alkalizing agent to an aluminum sulfate solution, continuing the reaction until the solid alkalizing agent is completely added, and then adding modified polyacrylamide and the polyaluminum sulfate modified quick-setting agent.

[0015] An application of a polyaluminum sulfate modified accelerator, which is applied to cement in an environment with an average annual UV index of 10-15.

[0016] The beneficial effects of this invention are:

[0017] This invention modifies polyacrylamide. First, 2-(2,4-dihydroxyphenyl)-2H-benzotriazole and 1,2,7,8-diepoxyoctane undergo a ring-opening reaction to obtain intermediate 1, a UV-resistant agent of benzotriazole. Then, another epoxy ring of intermediate 1 undergoes a ring-opening reaction with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine to obtain intermediate 2, which is both UV-resistant and antioxidant. Finally, intermediate 2 is grafted onto polyacrylamide to obtain modified polyacrylamide. This modified polyacrylamide, when combined with polyaluminum sulfate, effectively improves the antioxidant and UV-resistant capabilities of the modified polyaluminum sulfate quick-setting agent, thereby extending its service life. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1

[0020] This invention relates to a modified polyaluminum sulfate quick-setting agent, which comprises the following raw materials in parts by weight: 20 parts aluminum sulfate, 1 part solid alkalizing agent and 30 parts modified polyacrylamide.

[0021] A solid alkalizing agent is added to the aluminum sulfate solution. After the solid alkalizing agent is completely added, the reaction continues until it is complete. Then, modified polyacrylamide and polyaluminum sulfate modified quick-setting agent are added.

[0022] The preparation process of modified polyacrylamide includes the following steps:

[0023] Step 1: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole was dissolved in anhydrous ethanol solution and mixed with 0.1% Na2CO3 aqueous solution under nitrogen protection. Then 1,2,7,8-diepoxyoctane was added and the reaction was carried out at 80℃ for 7 hours to obtain intermediate 1.

[0024] The ratio of the aqueous solution of 2-(2,4-dihydroxyphenyl)-2H-benzotriazole, 1,2,7,8-dicyclooxyoctane, and 0.1% Na2CO3 was controlled to be 1 mol: 1: 1000 mL.

[0025] Step 2: Intermediate 1 is mixed with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid is added as a catalyst. The mixture is reacted for 10-20 h under a nitrogen atmosphere and at a temperature of 150 °C to obtain intermediate 2.

[0026] The ratio of intermediate 1, (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid was controlled to be 1 mol: 1 mol: 0.01 mol;

[0027] Step 3: Adjust the pH of a 1% polyacrylamide solution to 10 with a 10% sodium hydroxide solution, then add intermediate 2 and react at 45-60℃ for 1-3 hours to obtain modified polyacrylamide.

[0028] The ratio of polyacrylamide to intermediate 2 was controlled to be 1 mol: 0.4 mol.

[0029] Example 2

[0030] This invention relates to a modified polyaluminum sulfate quick-setting agent, which comprises the following raw materials in parts by weight: 40 parts aluminum sulfate, 4 parts solid alkalizing agent and 50 parts modified polyacrylamide.

[0031] A solid alkalizing agent is added to the aluminum sulfate solution. After the solid alkalizing agent is completely added, the reaction continues until it is complete. Then, modified polyacrylamide and polyaluminum sulfate modified quick-setting agent are added.

[0032] The preparation process of modified polyacrylamide includes the following steps:

[0033] Step 1: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole was dissolved in anhydrous ethanol solution and mixed with 0.1% Na2CO3 aqueous solution under nitrogen protection. Then 1,2,7,8-diepoxyoctane was added and the reaction was carried out at 80℃ for 7 hours to obtain intermediate 1.

[0034] The ratio of aqueous solution of 2-(2,4-dihydroxyphenyl)-2H-benzotriazole, 1,2,7,8-diepoxyoctane, and 0.1% Na2CO3 was controlled to be 1.1 mol: 1.1: 1400 mL.

[0035] Step 2: Intermediate 1 is mixed with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid is added as a catalyst. The mixture is reacted for 10-20 h under a nitrogen atmosphere and at a temperature of 150 °C to obtain intermediate 2.

[0036] The ratio of intermediate 1, (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid was controlled to be 1.1 mol: 1.1 mol: 0.01 mol;

[0037] Step 3: Adjust the pH of a 1% polyacrylamide solution to 10 with a 10% sodium hydroxide solution, then add intermediate 2 and react at 45-60℃ for 1-3 hours to obtain modified polyacrylamide.

[0038] The ratio of polyacrylamide to intermediate 2 was controlled to be 1.1 mol: 0.5 mol.

[0039] Example 3

[0040] This invention relates to a modified polyaluminum sulfate quick-setting agent, which comprises the following raw materials in parts by weight: 60 parts aluminum sulfate, 6 parts solid alkalizing agent and 70 parts modified polyacrylamide.

[0041] A solid alkalizing agent is added to the aluminum sulfate solution. After the solid alkalizing agent is completely added, the reaction continues until it is complete. Then, modified polyacrylamide and polyaluminum sulfate modified quick-setting agent are added.

[0042] The preparation process of modified polyacrylamide includes the following steps:

[0043] Step 1: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole was dissolved in anhydrous ethanol solution and mixed with 0.1% Na2CO3 aqueous solution under nitrogen protection. Then 1,2,7,8-diepoxyoctane was added and the reaction was carried out at 80℃ for 7 hours to obtain intermediate 1.

[0044] The ratio of aqueous solution of 2-(2,4-dihydroxyphenyl)-2H-benzotriazole, 1,2,7,8-dicyclooxyoctane, and 0.1% Na2CO3 was controlled to be 1.2 mol: 1.2 mol: 1800 mL.

[0045] Step 2: Intermediate 1 is mixed with (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid is added as a catalyst. The mixture is reacted for 10-20 h under a nitrogen atmosphere and at a temperature of 150 °C to obtain intermediate 2.

[0046] The ratio of intermediate 1, (1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and salicylic acid was controlled to be 1.2 mol: 1.2 mol: 0.01 mol;

[0047] Step 3: Adjust the pH of a 1% polyacrylamide solution to 10 with a 10% sodium hydroxide solution, then add intermediate 2 and react at 45-60℃ for 1-3 hours to obtain modified polyacrylamide.

[0048] The ratio of polyacrylamide to intermediate 2 was controlled to be 1.2 mol: 0.6 mol.

[0049] Example 4

[0050] Based on the above embodiments 1-3, the present invention provides a polyaluminum sulfate modified quick-setting agent, which is applied to cement in an environment with an annual average ultraviolet index of 10-15.

[0051] Comparative Example 1

[0052] Comparative Example 1 used polyaluminum sulfate modified quick-setting agent with patent number CN 114804713 A;

[0053] Performance tests were conducted on the polyaluminum sulfate modified quick-setting agents of Examples 1-3 and Comparative Example 1:

[0054] UPF Example 1 135 Example 2 129 Example 3 127 Comparative Example 1 90

[0055] As can be seen from the table above, the modified polyacrylamide prepared by this invention, when combined with polyaluminum sulfate, effectively improves the antioxidant and UV resistance of the modified polyaluminum sulfate quick-setting agent, thereby increasing its service life.

[0056] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A polyaluminum sulfate modified accelerator, characterized in that, The method comprises the following raw materials by weight: 20-60 parts of aluminum sulfate, 1-6 parts of solid alkaline agent and 30-70 parts of modified polyacrylamide; The preparation process of the modified polyacrylamide comprises the following steps: Step 1: 2-(2,4-dihydroxyphenyl)-2H-benzotriazole is dissolved in anhydrous ethanol solution, mixed with a 0.1% mass fraction Na2CO3 aqueous solution under nitrogen protection, then 1,2,7,8-diepoxyoctane is added, and the temperature is controlled at 80°C for 7h to obtain intermediate 1; Step 2: Intermediate 1 was mixed with (1,3-dimethylbutyl)-N ， - phenyl-p-phenylenediamine mixture, with the addition of salicylic acid as a catalyst, under a nitrogen atmosphere, at a temperature of 150°C, for a reaction time of 10-20 h, to obtain intermediate 2; Step 3: The 1% mass fraction polyacrylamide solution is adjusted to pH 10 with a 10% mass fraction sodium hydroxide solution, then intermediate 2 is added, and the reaction is carried out at a temperature of 45-60°C for 1-3h to obtain the modified polyacrylamide; The amount ratio of 2-(2,4-dihydroxyphenyl)-2H-benzotriazole, 1,2,7,8-diepoxyoctane and 0.1% mass fraction Na2CO3 aqueous solution is controlled to be 1-1.2mol:1-1.2mol:1000-1800mL; Control Intermediate 1, (1,3-dimethylbutyl)-N ， - phenyl-p-phenylenediamine, salicylic acid in a ratio of 1-1.2 mol: 1-1.2 mol: 0.01 mol; The amount ratio of polyacrylamide and intermediate 2 is controlled to be 1-1.2mol:0.4-0.6mol.

2. A method for preparing the polymerized aluminum sulfate modified accelerator according to claim 1, characterized in that, The solid alkaline agent is added into the aluminum sulfate solution, and after the addition of the solid alkaline agent is completed, the reaction is continued to be complete, and then the modified polyacrylamide is added to obtain the polymerized aluminum sulfate modified accelerator.

3. Use of the polymerized aluminum sulfate modified accelerator according to claim 1, characterized in that, The polymerized aluminum sulfate modified accelerator is applied to cement in an environment with an average annual ultraviolet index of 10-15.