Efficient soil water-retaining agent and preparation method thereof

Abstract

The invention provides an efficient soil water-retaining agent and a preparation method thereof, and belongs to the technical field of high polymer materials. The efficient soil water-retaining agent provided by the invention is prepared from the following raw materials in parts by mass: 1 to 5 parts of polyaspartic acid, 1 to 3 parts of bentonite, 10 to 50 parts of acrylic acid, 5 to 80 parts of alkaline substance, 0.002 to 0.4 part of cross-linking agent, 0.08 to 0.2 part of initiator and 10 to 300 parts of solvent. The polyaspartic acid contains a large number of carboxyl groups, water can be combined on a side chain of the polyaspartic acid, and a gel structure of the polyaspartic acid can absorb water in an electronic environment in space, so that the water absorption rate of the efficient soil water-retaining agent is improved; the bentonite has good water-retaining property and adsorbability, has strong cation exchange capacity, and can obviously improve the water absorption rate of the soil; acrylic acid contains a strong hydrophilic group carboxyl which can form a hydrogen bond with water, so that the water absorption of the efficient soil water-retaining agent is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to a high-efficiency soil water-retaining agent and a preparation method thereof. Background Art

[0002] Soil water-retaining agents are agricultural and forestry water-retaining agents, known as miniature reservoirs for plants. They can quickly absorb and retain rainwater or irrigation water in the soil without leakage, thereby ensuring sufficient water in the rhizosphere range and slowly releasing it for plant utilization. Their unique water absorption, water storage, and water retention properties play a decisive role in improving the ecological environment and sand fixation projects, and are widely used in fields such as land desertification control, planting of agricultural and forestry crops, and landscaping.

[0003] Currently, the soil water-retaining agent is an acrylamide-type water-retaining agent, which has the problem of low water absorption rate. Therefore, how to improve the water absorption rate of the soil water-retaining agent has become an urgent technical problem in this field. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-efficiency soil water-retaining agent and a preparation method thereof. The high-efficiency soil water-retaining agent provided by the present invention has excellent water absorption rate.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a high-efficiency soil water-retaining agent, which comprises the following raw materials in parts by mass: 1-5 parts of polyaspartic acid, 1.0-3 parts of bentonite, 10-50 parts of acrylic acid, 5-80 parts of alkaline substance, 0.002-0.4 parts of crosslinking agent, 0.08-0.2 parts of initiator, and 10-300 parts of solvent.

[0007] Preferably, it comprises the following raw materials in parts by mass: 2-4 parts of polyaspartic acid, 1.0-2.5 parts of bentonite, 14-45 parts of acrylic acid, 10-70 parts of alkaline substance, 0.005-0.03 parts of crosslinking agent, 0.09-0.15 parts of initiator, and 50-250 parts of solvent.

[0008] Preferably, the alkaline substance comprises at least one of sodium hydroxide, potassium hydroxide, and sodium carbonate.

[0009] Preferably, the crosslinking agent comprises at least one of N,N'-methylenebisacrylamide, dimethyldiallylammonium chloride, triallylammonium chloride, and tetraallylammonium chloride.

[0010] Preferably, the initiator comprises a mixture of potassium persulfate and sodium thiosulfate, a mixture of potassium persulfate and sodium bisulfite, potassium persulfate, or ammonium persulfate.

[0011] Preferably, the particle size of the high-efficiency soil water-retaining agent is 20-60 mesh.

[0012] The present invention also provides a preparation method of the high-efficiency soil water retainer described in the above technical solution, including:

[0013] Mix polyaspartic acid, bentonite, acrylic acid, alkaline substance, crosslinking agent, initiator and solvent, and carry out crosslinking to obtain the high-efficiency soil water retainer.

[0014] Preferably, the crosslinking is carried out under microwave radiation conditions.

[0015] Preferably, the power of the microwave radiation is 200-700 W; the time of the microwave radiation is 1-6 min.

[0016] Preferably, the power of the microwave radiation is 210-560 W.

[0017] The present invention provides a high-efficiency soil water retainer, which comprises the following raw materials in parts by mass: 1-5 parts of polyaspartic acid, 1-3 parts of bentonite, 10-50 parts of acrylic acid, 5-80 parts of alkaline substance, 0.002-0.4 parts of crosslinking agent, 0.08-0.2 parts of initiator and 10-300 parts of solvent. In the present invention, polyaspartic acid contains a large number of carboxyl groups, which can combine water on the side chain of polyaspartic acid. The gel structure of polyaspartic acid can absorb water in the electronic environment spatially, thereby improving the water absorption rate of the high-efficiency soil water retainer; bentonite has good water retention and adsorption properties, and its cation exchange capacity is strong, which can significantly improve the water absorption rate of the soil; acrylic acid contains a strong hydrophilic group carboxyl, which can form hydrogen bonds with water to improve the water absorption rate of the high-efficiency soil water retainer; acrylic acid and polyaspartic acid will form a three-dimensional network structure under the action of a crosslinking agent and an initiator, further enhancing the water absorption rate of the high-efficiency soil water retainer. The experimental results show that the water absorption rate of the high-efficiency soil water retainer provided by the present invention can reach 468.97253 g / g. Description of the Drawings

[0018] Figure 1 Curves of the water absorption rates of the high-efficiency soil water retainers prepared in Examples 1-8;

[0019] Figure 2 Curves of the water absorption rates of the high-efficiency soil water retainers prepared in Examples 9-13;

[0020] Figure 3 Curves of the water absorption rates of the high-efficiency soil water retainers prepared in Example 11 and Examples 14-17;

[0021] Figure 4 Water absorption rates of the high-efficiency soil water retainer prepared in Example 11 and the soil water retainers prepared in Comparative Examples 1-2. Detailed Embodiments

[0022] The present invention provides an efficient soil water retainer, which comprises the following raw materials in parts by mass: 1-5 parts of polyaspartic acid, 1-3 parts of bentonite, 10-50 parts of acrylic acid, 5-80 parts of alkaline substance, 0.002-0.4 parts of crosslinking agent, 0.08-0.2 parts of initiator, and 10-300 parts of solvent.

[0023] The present invention has no special limitation on the sources of the various raw materials, and commercially available products well-known to those skilled in the art can be used.

[0024] In parts by mass, the raw materials for preparing the efficient soil water retainer of the present invention include 1-5 parts of polyaspartic acid (PASP). As an embodiment, the mass parts of the polyaspartic acid can be 1.5 parts, 2 parts, 2.102 parts, 2.5 parts, 3 parts or 4 parts. In the present invention, polyaspartic acid contains a large number of carboxyl groups, and water can be bound to the side chain of polyaspartic acid; the gel structure of polyaspartic acid can absorb water in the electronic environment spatially, thereby improving the water absorption rate of the efficient soil water retainer.

[0025] In the present invention, the mass parts of the polyaspartic acid are preferably 2.102 parts.

[0026] The present invention has no special limitation on the molecular weight of the polyaspartic acid, and polyaspartic acid well-known to those skilled in the art can be used.

[0027] Based on 1-5 parts by mass of polyaspartic acid, the raw materials for preparing the efficient soil water retainer of the present invention include 1-3 parts of bentonite (BT). As an embodiment, the mass parts of the bentonite can be 1.2612 parts, 1.5 parts, 2 parts or 2.5 parts. In the present invention, bentonite has good water retention and adsorption properties, and its cation exchange capacity is strong, which can significantly improve the water absorption rate of the soil.

[0028] Based on 1-5 parts by mass of polyaspartic acid, the raw materials for preparing the efficient soil water retainer of the present invention include 10-50 parts of acrylic acid (AA). As an embodiment, the mass parts of the acrylic acid can be 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts or 45 parts. In the present invention, acrylic acid contains a strong hydrophilic group carboxyl, which can form hydrogen bonds with water, thereby improving the water absorption rate of the efficient soil water retainer.

[0029] Based on 1-5 parts by mass of polyaspartic acid, the raw materials for preparing the efficient soil water retainer of the present invention include 5-80 parts of alkaline substance. As an embodiment, the mass parts of the alkaline substance can be 10 parts, 17.50212 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts or 70 parts. In the present invention, the alkaline substance is used to neutralize acrylic acid.

[0030] In the present invention, the alkaline substance preferably includes at least one of sodium hydroxide, potassium hydroxide and sodium carbonate, and more preferably sodium hydroxide.

[0031] Based on 1 to 5 parts by mass of polyaspartic acid, the raw materials for preparing the high-efficiency soil water-retaining agent of the present invention include 0.002 to 0.4 parts of a cross-linking agent. As an embodiment, the mass fraction of the cross-linking agent can be 0.002102 parts, 0.004504 parts, 0.005 parts, 0.006 parts, 0.007 parts, 0.008 parts, 0.008408 parts, 0.009 parts, 0.01 parts, 0.012612 parts, 0.015 parts, 0.02 parts, 0.02102 parts, 0.025 parts or 0.03 parts. In the present invention, the cross-linking agent can cause the system to undergo a cross-linking reaction to form a three-dimensional network structure.

[0032] In the present invention, the crosslinking agent preferably includes at least one of N,N'-methylenebisacrylamide (MBA), dimethyldiallylammonium chloride, triallylammonium chloride and tetraallylammonium chloride, and more preferably N,N'-methylenebisacrylamide. In the present invention, the N,N'-methylenebisacrylamide is a vinyl crosslinking agent containing multiple terminal olefinic bonds, and the double bonds on the crosslinking agent molecules directly participate in the free radical copolymerization reaction, thereby improving the uniformity of the crosslinking network.

[0033] Based on 1 to 5 parts by mass of polyaspartic acid, the raw materials for preparing the high-efficiency soil water-retaining agent of the present invention include 0.08 to 0.2 parts of initiator. As an embodiment, the mass fraction of the initiator can be 0.08408 parts, 0.09 parts, 0.1 parts, 0.1 parts, 0.1051 parts, 0.11 parts, 0.12612 parts, 0.1138 parts, 0.12 parts, 0.13 parts, 0.1366 parts, 0.14 parts, 0.14714 parts, 0.15 parts, 0.16 parts, 0.16816 parts, 0.17 parts, 0.18 parts or 0.19 parts. In the present invention, the initiator is used to initiate a polymerization reaction.

[0034] In the present invention, the initiator preferably includes a mixture of potassium persulfate and sodium thiosulfate, a mixture of potassium persulfate and sodium bisulfite, potassium persulfate or ammonium persulfate, and more preferably potassium persulfate (KPS).

[0035] Based on 1 to 5 parts by mass of polyaspartic acid, the raw materials for preparing the high-efficiency soil water-retaining agent of the present invention include 10 to 300 parts by mass of solvent. As an embodiment, the mass of the solvent can be 50 parts, 70 parts, 100 parts, 120 parts, 140 parts, 150 parts, 200 parts, 250 parts or 280 parts. In the present invention, the solvent is used to dissolve the raw materials.

[0036] In the present invention, the solvent is preferably an inorganic solvent, and more preferably distilled water.

[0037] In the present invention, the particle size of the high-efficiency soil water-retaining agent is preferably 20 to 60 mesh. As an embodiment, the particle size of the high-efficiency soil water-retaining agent can be 30 mesh, 40 mesh or 50 mesh. In the present invention, within the above range, the particle size of the high-efficiency soil water-retaining agent can improve the water absorption rate of the high-efficiency soil water-retaining agent.

[0038] In the present invention, polyaspartic acid contains a large number of carboxyl groups, which can bind water on the side chain of polyaspartic acid. The gel structure of polyaspartic acid can absorb water in the electronic environment in space, thereby improving the water absorption rate of the high-efficiency soil water-retaining agent; bentonite has good water retention and adsorption properties, and its strong cation exchange capacity can significantly improve the water absorption rate of the soil; acrylic acid contains a strongly hydrophilic group carboxyl, which can form hydrogen bonds with water to improve the water absorption rate of the high-efficiency soil water-retaining agent; acrylic acid will form a three-dimensional network structure under the action of a cross-linking agent and an initiator, further enhancing the water absorption rate of the high-efficiency soil water-retaining agent.

[0039] The water absorption rate of the high-efficiency soil water-retaining agent provided by the present invention is more than twice that of the commercial water-retaining agent; selecting polyaspartic acid and bentonite as the main production materials is environmentally friendly and can be naturally degraded without pollution to the environment; the high-efficiency soil water-retaining agent provided by the present invention has a polymer structure and is a biodegradable material, enhancing the water absorption rate; bentonite is a non-metallic mineral mainly composed of montmorillonite, with good water retention and adsorption properties; bentonite can adsorb 8 to 15 times its own volume of water and can form a dispersed suspension gel with a certain viscosity and lubricity; bentonite has a strong cation exchange capacity and can be used to improve the soil and increase the water absorption rate of the soil.

[0040] In the present invention, polyaspartic acid contains carboxyl - COO - , when absorbing water, first, the ionic hydrophilic groups start to dissociate under the action of water molecules to obtain - COO - and Na + , H + and other ions. The anions are fixed on the polymer chain, while the cations act as mobile ions inside the resin to maintain electrical neutrality. As the dissociation process proceeds, the number of anions on the polymer chain increases, and the electrostatic repulsion between ions causes the resin to swell; because - COO - on the polymer chain cannot diffuse into the water, and the concentration of Na + in the network structure is greater than the concentration of Na + in the water, so a concentration difference is generated, causing the water outside the polymer network structure to penetrate into the network structure to achieve the balance of the Na + concentration inside and outside the network structure; secondly, due to - COO in the network structure- After ionization, the concentration of ions with the same charge increases, resulting in an increase in repulsive force and the expansion of the network structure. At the same time, the hydrophilic groups -COO - and -CONH- in the network structure can form hydrogen bonds with water. Therefore, when the soil water retainer encounters water, it can quickly fix and absorb water into a gel state and store it in the soil water retainer.

[0041] The present invention also provides a preparation method of the high-efficiency soil water retainer described in the above technical solution, including:

[0042] Mix polyaspartic acid, bentonite, acrylic acid, alkaline substance, crosslinking agent, initiator and solvent, and carry out crosslinking to obtain the high-efficiency soil water retainer.

[0043] In the present invention, the mixing of polyaspartic acid, bentonite, acrylic acid, alkaline substance, crosslinking agent, initiator and solvent is preferably as follows:

[0044] (1) Mix the alkaline substance and the solvent to obtain an alkaline solution;

[0045] (2) Mix the alkaline solution obtained in step (1) with acrylic acid and carry out a neutralization reaction to obtain a reaction solution;

[0046] (3) Mix the reaction solution obtained in step (2), polyaspartic acid and bentonite, and then mix with the crosslinking agent and the initiator.

[0047] The present invention has no special limitation on the operation of mixing the alkaline substance and the solvent, and the technical solution of preparing a mixed material well-known to those skilled in the art can be adopted.

[0048] The present invention has no special limitation on the operation of mixing the alkaline solution and acrylic acid, and the technical solution of preparing a mixed material well-known to those skilled in the art can be adopted.

[0049] In the present invention, the neutralization reaction is preferably carried out in an ice-water bath. The present invention has no special limitation on the time of the neutralization reaction, and it is sufficient until the degree of the neutralization reaction reaches within the range of 70-80%.

[0050] After the neutralization reaction is completed, the present invention preferably cools the product obtained from the neutralization reaction to obtain a reaction solution.

[0051] The present invention has no special limitation on the operation of the cooling, and the operation well-known to those skilled in the art of cooling to room temperature can be adopted.

[0052] The present invention has no special limitation on the operation of mixing the reaction solution, polyaspartic acid and bentonite, and the technical solution of preparing a mixed material well-known to those skilled in the art can be adopted.

[0053] The present invention has no special limitation on the operation of remixing with the crosslinking agent and the initiator, and the technical solutions for preparing the mixed material well-known to those skilled in the art can be adopted.

[0054] In the present invention, the crosslinking is preferably carried out under microwave radiation conditions; the power of the microwave radiation is preferably 200-700 W; the time of the microwave radiation is preferably 1-6 min. As an implementation manner, the power of the microwave radiation can be 210 W, 300 W, 350 W, 400 W, 450 W or 560 W; the time of the microwave radiation can be 2 min, 3 min, 4 min or 5 min. Limiting the power and time of the microwave radiation within the above ranges in the present invention can improve the crosslinking degree, thereby improving the water absorption rate of the high-efficiency soil water retainer.

[0055] In the present invention, the crosslinking is preferably carried out in a microwave oven. The present invention has no special limitation on the model of the microwave oven, and the instrument equipment well-known to those skilled in the art can be adopted.

[0056] After the crosslinking is completed, the present invention preferably cools, soaks, dries, crushes and sieves the product obtained by the crosslinking in sequence to obtain the high-efficiency soil water retainer.

[0057] The present invention has no special limitation on the cooling operation, and the operation well-known to those skilled in the art can be adopted to cool to room temperature.

[0058] In the present invention, the reagent used for the soaking is preferably ethanol. The present invention has no special limitation on the soaking time, and the residual monomers can be removed.

[0059] The present invention has no special limitation on the drying operation, and it can be dried to a constant weight.

[0060] The present invention has no special limitation on the crushing operation, and the operation well-known to those skilled in the art can be adopted.

[0061] The present invention has no special limitation on the sieving operation, and it can be sieved according to the required particle size.

[0062] The present invention adopts the microwave radiation method, and the manufacturing method is simple, time-consuming is short, the cost is low, and it is suitable for large-scale production.

[0063] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the scope of protection of the present invention.

[0064] Example 1

[0065] An efficient soil water retainer is composed of the following raw materials in parts by mass: 2.102 parts of polyaspartic acid, 1.2612 parts of bentonite, 40 parts of acrylic acid, 17.50212 parts of alkaline substance, 0.012612 parts of crosslinking agent, 0.12612 parts of initiator, and 70 parts of solvent;

[0066] The polyaspartic acid is produced by Desai Chemical Co., Ltd. in Shijiazhuang, China;

[0067] The bentonite is produced by Tianjin Damao Chemical Reagent Factory;

[0068] The alkaline substance is sodium hydroxide;

[0069] The crosslinking agent is N,N'-methylenebisacrylamide;

[0070] The initiator is potassium persulfate;

[0071] The particle size of the efficient soil water retainer is 20 mesh;

[0072] The solvent is distilled water;

[0073] The preparation method of the efficient soil water retainer is as follows:

[0074] (1) Mix the alkaline substance and the solvent to obtain an alkaline solution;

[0075] (2) Add acrylic acid into a beaker, and in an ice-water bath environment, add the alkaline solution obtained in the above step (1) and mix to carry out a neutralization reaction. The degree of neutralization is 75%, and then cool to room temperature to obtain a reaction solution;

[0076] (3) Add polyaspartic acid and bentonite into the reaction solution obtained in the above step (2) in sequence. After stirring, then add the crosslinking agent and the initiator, stir evenly again, then transfer to a microwave oven, carry out crosslinking for 5 min under 210W microwave radiation, then cool to room temperature, then soak in an ethanol solution for 12 h, then place in a drying oven at 75°C for drying for 24 h, and then carry out crushing and sieving in sequence to obtain the efficient soil water retainer.

[0077] Example 2

[0078] On the basis of Example 1, change the power of microwave radiation to 350W and the crosslinking time to 3 min, and keep other conditions unchanged to obtain the efficient soil water retainer.

[0079] Example 3

[0080] On the basis of Example 1, change the power of microwave radiation to 560W and the crosslinking time to 2 min, and keep other conditions unchanged to obtain the efficient soil water retainer.

[0081] Example 4

[0082] Based on Example 1, the power of microwave radiation was changed to 700 W and the cross-linking time was 1 min, while other conditions remained unchanged, and a highly efficient soil water retainer was obtained.

[0083] Example 5

[0084] Based on Example 1, only the particle size of the highly efficient soil water retainer was changed to 60 mesh, while other conditions remained unchanged, and a highly efficient soil water retainer was obtained.

[0085] Example 6

[0086] Based on Example 2, only the particle size of the highly efficient soil water retainer was changed to 60 mesh, while other conditions remained unchanged, and a highly efficient soil water retainer was obtained.

[0087] Example 7

[0088] Based on Example 3, only the particle size of the highly efficient soil water retainer was changed to 60 mesh, while other conditions remained unchanged, and a highly efficient soil water retainer was obtained.

[0089] Example 8

[0090] Based on Example 4, only the particle size of the highly efficient soil water retainer was changed to 60 mesh, while other conditions remained unchanged, and a highly efficient soil water retainer was obtained.

[0091] The water absorption rates of the highly efficient soil water retainers prepared in Examples 1 to 8 were tested, and the results are as Figure 1 shown. The method for water absorption rate test was as follows:

[0092] Accurately weigh 1 g of the sample (accurate to 0.01 g), place it in a 2000 mL beaker, add 1000 mL of tap water, stir for 5 min, and let it stand for 30 min to allow the sample to fully absorb water and swell. Transfer the gel-like sample into a standard test sieve of known mass (100-mesh stainless steel screen), filter for 10 min, place the test sieve at an angle, filter for another 10 min, weigh the mass of the test sieve and the gel-like sample, and the water absorption multiple V is expressed in g / g. The water absorption rate is calculated according to Equation I:

[0093]

[0094] In the formula, m1 is the mass of the water absorbent and swelling equilibrium water retainer, in g; m2 is the mass of the blank test, in g; m is the mass of the water retainer sample, in g.

[0095] Figure 1 are the water absorption rate curves of the highly efficient soil water retainers prepared in Examples 1 to 8.

[0096] From Figure 1It can be seen that when the particle size of the high-efficiency soil water-retaining agent is 20 mesh and the power of microwave radiation is 350 W, the water absorption rate of the high-efficiency soil water-retaining agent is the highest.

[0097] Example 9

[0098] On the basis of Example 2, only the amount of cross-linking agent is changed to 0.002102 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0099] Example 10

[0100] On the basis of Example 2, only the amount of cross-linking agent is changed to 0.004504 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0101] Example 11

[0102] On the basis of Example 2, only the amount of cross-linking agent is changed to 0.008408 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0103] Example 12

[0104] On the basis of Example 2, only the amount of cross-linking agent is changed to 0.012612 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0105] Example 13

[0106] On the basis of Example 2, only the amount of cross-linking agent is changed to 0.02102 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0107] According to the method for testing water absorption rate described above, the water absorption rates of the high-efficiency soil water-retaining agents prepared in Examples 9 to 13 are tested, and the results are as Figure 2 shown.

[0108] Figure 2 is the water absorption rate curve of the high-efficiency soil water-retaining agents prepared in Examples 9 to 13.

[0109] From Figure 2 it can be seen that when the cross-linking agent is 0.008408 parts, the water absorption rate is the highest, reaching 468.97253 g / g.

[0110] Example 14

[0111] On the basis of Example 11, only the amount of initiator is changed to 0.08408 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0112] Example 15

[0113] On the basis of Example 11, only the amount of initiator is changed to 0.1051 parts, and other conditions remain unchanged, to obtain a high-efficiency soil water-retaining agent.

[0114] Example 16

[0115] Based on Example 11, only the amount of initiator was changed to 0.14714 parts, and other conditions remained unchanged, obtaining a highly efficient soil water retention agent.

[0116] Example 17

[0117] Based on Example 11, only the amount of initiator was changed to 0.16816 parts, and other conditions remained unchanged, obtaining a highly efficient soil water retention agent.

[0118] According to the method for testing water absorption rate described above, the water absorption rates of the highly efficient soil water retention agents prepared in Example 11 and Examples 14 - 17 were tested, and the results are as Figure 3 shown.

[0119] Figure 3 The water absorption rate curves of the highly efficient soil water retention agents prepared in Example 11 and Examples 14 - 17.

[0120] From Figure 3 it can be seen that when the initiator is 0.12612 parts, the water absorption rate is the highest, reaching 468.97253 g / g.

[0121] Comparative Example 1

[0122] Polyaspartic acid (PASP) + sodium alginate, and the mass ratio of polyaspartic acid to sodium alginate is 5:2.

[0123] Comparative Example 2

[0124] Commercially available water retention agent (Qingdao Shouke water retention agent SHK)

[0125] According to the method for testing water absorption rate described above, the water absorption rates of the highly efficient soil water retention agent prepared in Example 11 and the soil water retention agents prepared in Comparative Examples 1 - 2 were tested, and the results are as Figure 4 shown.

[0126] Figure 4 The water absorption rates of the highly efficient soil water retention agent prepared in Example 11 and the soil water retention agents prepared in Comparative Examples 1 - 2.

[0127] From Figure 4 it can be seen that the water absorption rate of the highly efficient soil water retention agent provided by the present invention can reach 468.97253 g / g, which is more than twice that of the commercially available water retention agent.

[0128] From the above examples and comparative examples, it can be seen that the highly efficient soil water retention agent provided by the present invention has excellent water absorption rate.

[0129] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. An efficient soil water retainer, characterized in that, It comprises raw materials in the following parts by mass: 1 to 5 parts of polyaspartic acid, 1.0 to 3 parts of bentonite, 10 to 50 parts of acrylic acid, 5 to 80 parts of alkaline substance, 0.002 to 0.4 parts of crosslinking agent, 0.08 to 0.2 parts of initiator, and 10 to 300 parts of solvent.

2. The high-efficiency soil water retainer according to claim 1, wherein It comprises raw materials in the following parts by mass: 2 to 4 parts of polyaspartic acid, 1.0 to 2.5 parts of bentonite, 14 to 45 parts of acrylic acid, 10 to 70 parts of alkaline substance, 0.005 to 0.03 parts of crosslinking agent, 0.09 to 0.15 parts of initiator, and 50 to 250 parts of solvent.

3. The high-efficiency soil water retainer according to claim 1 or 2, characterized in that, The alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, and sodium carbonate.

4. The high-efficiency soil water retainer according to claim 1 or 2, characterized in that, The crosslinking agent includes at least one of N,N'-methylenebisacrylamide, dimethyldiallylammonium chloride, triallylammonium chloride, and tetraallylammonium chloride.

5. The high-efficiency soil water retainer according to claim 1 or 2, characterized in that The initiator includes a mixture of potassium persulfate and sodium thiosulfate, a mixture of potassium persulfate and sodium bisulfite, potassium persulfate, or ammonium persulfate.

6. The high-efficiency soil water retention agent according to claim 1, characterized in that The particle size of the high-efficiency soil water retainer is 20 to 60 mesh.

7. The preparation method of the high-efficiency soil water-retaining agent according to any one of claims 1 to 6, characterized in that, It includes: Mix polyaspartic acid, bentonite, acrylic acid, alkaline substance, crosslinking agent, initiator, and solvent, and carry out crosslinking to obtain a high-efficiency soil water retainer.

8. The preparation method according to claim 7, characterized in that, The crosslinking is carried out under microwave radiation conditions.

9. The preparation method according to claim 8, characterized in that, The power of the microwave radiation is 200 to 700 W; the time of the microwave radiation is 1 to 6 min.

10. The preparation method according to claim 8 or 9, characterized in that, The power of the microwave radiation is 210 to 560 W.

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