High-performance rapid-hardening hydrogel soil stabilizer as well as preparation method and application thereof
By achieving rapid free radical polymerization under aerobic conditions, hydrogel soil stabilizers with high mechanical properties and swelling resistance were prepared, which solved the problem of long curing time and insufficient mechanical properties of existing hydrogel soil stabilizers, and reduced the risk of environmental pollution.
Patent Information
- Application Number
- CN202510197879.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-21
- Publication Date
- 2025-06-06
AI Technical Summary
The existing hydrogel soil stabilizer has a long curing time and insufficient mechanical properties, making it difficult to meet the emergency needs of geological disaster prevention and control, and its production and application have environmental pollution problems.
A hydrogel soil stabilizer with high mechanical properties and anti-swelling properties is prepared by a hydrogel precursor solution composed of acrylamide monomer, acrylic monomer, catalyst, initiator and water.
The curing time of the hydrogel is significantly shortened, the mechanical properties are significantly improved, the toughness can reach more than 30MJ/m3, and the strength can reach more than 300MPa, while reducing the risk of environmental pollution.
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Figure CN120098183A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of engineering materials, and in particular relates to a high-performance quick-setting hydrogel soil stabilizer and a preparation method and application thereof. Background Art
[0002] Geological disasters are geological actions or phenomena caused by natural or human factors that cause loss of human life and property and damage to the environment. In Southwest my country, especially in the mountainous areas around the Sichuan Basin and the Yunnan-Guizhou Plateau, due to its complex topography and diverse climatic conditions, geological disasters such as landslides and mud-rock flows frequently occur, which has brought serious obstacles to local social and economic development. It is estimated that the economic losses caused by geological disasters in the southwest region are as high as tens of billions of yuan each year, and there is a trend of increasing year by year; at the same time, these disasters also pose a huge threat to people's lives and safety, which highlights the urgency of preventing and controlling geological disasters. One of the key reasons for the frequent occurrence of these disasters is the instability of the soil, so achieving soil stability is crucial to reducing the risks and impacts of future geological disasters.
[0003] Rapid soil stabilization technology plays an important role in the management and prevention of geological disasters such as landslides and mudslides. The principle is that when these geological disasters are about to occur or have just occurred, by quickly solidifying unstable soil, the further development of the disaster can be effectively curbed, and precious time can be gained for rescue work and post-disaster reconstruction. Rapid soil stabilization technology can not only respond quickly to emergencies, but also stabilize the soil for a long time to reduce disaster risks, providing an efficient solution for the prevention and control of geological disasters such as landslides. Among them, adding chemical stabilizers such as cement and concrete to the soil has been proven to be an effective strategy. However, cement and concrete materials themselves have poor fluidity and limited penetration depth in the soil, which often leads to the stabilization of the surface soil and is difficult to effectively solve the instability of deep soil. In addition, its production and application involve the use of heavy machinery and huge energy consumption, resulting in increased emissions of carbon dioxide and hazardous waste, causing serious environmental problems. Therefore, it is particularly important to develop a new rapid stabilization technology that can penetrate deeply and reduce environmental hazards.
[0004] The application of hydrogel soil stabilizers is simple and fast. Just pour the prepared hydrogel precursor into the target area and stabilize the soil in the area after in-situ curing. Secondly, hydrogels are usually gelled using low-viscosity precursors to ensure good permeability. More importantly, compared with other developed organic or inorganic soil stabilizers, the strength of hydrogel-stabilized soil is comparable to that of cement-stabilized soil. However, existing hydrogel stabilizers take a long time to cure and easily absorb water and swell violently, resulting in greatly reduced mechanical properties.
[0005] The literature (DOI: 10.1021 / acs.chemmater.2c02350) reported a waterproof hydrogel soil stabilizer containing methacrylic acid and acrylamide, but the mechanical properties of the hydrogel are poor and need to be further improved. At the same time, its curing time is long, which makes it difficult to meet the emergency needs of geological disaster prevention and control. Summary of the invention
[0006] In view of the problems existing in the prior art, the present invention proposes a method for realizing rapid polymerization of free radicals under aerobic conditions, and quickly preparing a hydrogel with high mechanical properties and anti-swelling properties under harsh conditions, which is used as a soil stabilizer.
[0007] The purpose of the present invention is to provide a high-performance quick-setting hydrogel soil stabilizer and a preparation method and application thereof.
[0008] The invention provides a hydrogel precursor solution, which consists of acrylamide monomer, acrylic acid monomer, catalyst, initiator and water, wherein the acrylamide monomer is methacrylamide and acrylamide; the ratio of methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1-5M: 0-7M: 5-10M: 0-0.5M: 0.01-0.5M: 10-35ml.
[0009] Furthermore, the ratio of the methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1.96M:5.63M:7.75M:0-0.5M:0.03M:10-35ml.
[0010] Furthermore, the ratio of the methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1.96M:5.63M:7.75M:0.07M:0.03M:15ml.
[0011] The unit "M" means "mol / L".
[0012] Furthermore, the acrylic acid monomer is methacrylic acid; the catalyst is a boron-containing hydroxy compound; and the initiator is persulfate.
[0013] "Boron-containing hydroxyl compounds" refer to compounds that contain both boron (B) elements and hydroxyl (-OH) groups in their molecular structures. The characteristic of this type of compound is that the boron atom is directly or indirectly bonded to the hydroxyl group to form a specific chemical structure.
[0014] Furthermore, the acrylic acid monomer is methacrylic acid; the catalyst is tetrahydroxydiboron; and the initiator is potassium persulfate.
[0015] The present invention also provides a method for preparing the hydrogel precursor solution, which comprises the following steps: mixing methacrylamide, acrylic acid monomer, a catalyst and water, and then adding acrylamide and an initiator to obtain a hydrogel.
[0016] The invention also provides a hydrogel, which is a product obtained by gelling the hydrogel precursor solution.
[0017] The present invention also provides a method for preparing the hydrogel, which comprises the following steps: gelling a hydrogel precursor solution to obtain the hydrogel.
[0018] The present invention also provides uses of the hydrogel precursor solution and the hydrogel in preparing soil engineering materials.
[0019] Furthermore, the soil engineering material is a soil stabilizer.
[0020] The present invention uses MAAc (methacrylic acid), MAAm (methacrylamide), and AM (acrylamide) as main raw materials, and utilizes hydrophilic THDB (tetrahydroxydiboron) and potassium persulfate (KPS) to achieve rapid preparation of free radical polymerization hydrogel under aerobic conditions. The present invention optimizes the content of THDB and water, screens and obtains the preferred ratio shown in Example 1, and prepares a physically cross-linked hydrogel soil stabilizer. The hydrogel soil stabilizer has excellent mechanical properties and anti-swelling properties.
[0021] The present invention adopts MAAc, MAAm and AM to copolymerize to form a polymer network, and introduces THDB to induce rapid gelation, so as to prepare a high-performance quick-setting hydrogel soil stabilizer, which can guide the rapid quantitative preparation of high-performance hydrogels in harsh environments, meet the stringent requirements of the soil stabilization field on the curing time, permeability and high performance of hydrogels, and provide an effective solution strategy for the prevention and management of geological disasters.
[0022] Compared with the hydrogel soil stabilizer reported in the literature (DOI: 10.1021 / acs.chemmater.2c02350), the curing time of the hydrogel soil stabilizer prepared by the present invention is shortened from several hours to about 20 minutes, which meets the demand for rapid soil stabilization; in addition, its mechanical properties are significantly improved, and its toughness can reach 30MJ / m 3 The strength can reach more than 300MPa; while the toughness of hydrogel soil stabilizer reported in the literature is only 2.1MJ / m 3 The innovation of the present invention is that the rapid gelation process induced by THDB drives the hydrogel to form a unique inhomogeneous network structure and microphase separation structure, which is beneficial to improving the mechanical properties and anti-swelling properties of the hydrogel.
[0023] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.
[0024] The above contents of the present invention are further described in detail below through specific implementation methods in the form of examples. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 Effects of tetrahydroxydiboron (THDB) on hydrogels with and without THDB: (a) gelation time; (b) infrared total reflection spectrum; (c) ultraviolet spectrum; (d) small-angle X-ray diffraction pattern; (e) tensile stress-strain curve; (f) material toughness and Young's modulus.
[0026] Figure 2 The effect of different contents of tetrahydroxydiboron (THDB) on the gelation time.
[0027] Figure 3 The effect of different water contents on anti-swelling properties.
[0028] Figure 4 Mechanical properties test results of hydrogel soil stabilizer: (a) Effect of different THDB contents on stress; (b) Effect of different THDB contents on toughness and Young's modulus; (c) Effect of different water contents on stress; (d) Effect of different water contents on toughness and Young's modulus. DETAILED DESCRIPTION
[0029] The raw materials and equipment used in the present invention are all known products, which are obtained by purchasing commercially available products.
[0030] Example 1. Preparation of high performance quick-setting hydrogel
[0031] 1.96M (mol / L) methacrylamide (MAAm), 7.75M methacrylic acid (MAAc) and 0.07M tetrahydroxydiboron (THDB) were dissolved in 15g (i.e. 15ml) of deionized water. After 15 minutes, 5.63M acrylamide (AM) and 0.03M potassium persulfate (KPS) were added to the solution to obtain a hydrogel precursor solution, which was gelled to obtain a high-performance quick-setting hydrogel, recorded as B0.1 / B0.10 or H15.
[0032] Example 2: Preparation of high performance quick-setting hydrogel
[0033] Referring to the method of Example 1, the only difference is that 0.07M THDB is replaced by 0.04M to prepare a hydrogel precursor solution, which is gelled to obtain a high-performance rapid-setting hydrogel, denoted as B0.05.
[0034] Example 3: Preparation of high performance quick-setting hydrogel
[0035] Referring to the method of Example 1, the only difference is that 0.07M THDB is replaced by 0.11M to prepare a hydrogel precursor solution, which is gelled to obtain a high-performance rapid-setting hydrogel, which is recorded as B0.15.
[0036] Example 4: Preparation of high performance quick-setting hydrogel
[0037] Referring to the method of Example 1, the only difference is that 0.07M THDB is replaced by 0.15M to prepare a hydrogel precursor solution, and the high-performance rapid-setting hydrogel is obtained by gelation, which is recorded as B0.2 / B0.20.
[0038] Example 5: Preparation of high performance quick-setting hydrogel
[0039] The method of Example 1 was referred to, except that 0.07 M THDB was replaced with 0.19 M to prepare a hydrogel precursor solution, which was gelled to obtain a high-performance rapid-setting hydrogel, denoted as B0.25.
[0040] Example 6: Preparation of high performance quick-setting hydrogel
[0041] The method of Example 1 was used with reference to that of Example 1, except that 15 g of deionized water was replaced by 10 g to prepare a hydrogel precursor solution, which was then gelled to obtain a high-performance rapid-setting hydrogel, which was recorded as H10.
[0042] Example 7: Preparation of high performance quick-setting hydrogel
[0043] The method of reference example 1 is different in that 15 g of deionized water is replaced by 20 g to prepare a hydrogel precursor solution, which is gelled to obtain a high-performance rapid-setting hydrogel, denoted as H20.
[0044] Example 8: Preparation of high performance quick-setting hydrogel
[0045] The method of reference example 1 is different in that 15 g of deionized water is replaced by 25 g to prepare a hydrogel precursor solution, which is gelled to obtain a high-performance rapid-setting hydrogel, which is recorded as H25.
[0046] Example 9: Preparation of high performance quick-setting hydrogel
[0047] The method of reference example 1 is different in that 15 g of deionized water is replaced by 30 g to prepare a hydrogel precursor solution, which is gelled to obtain a high-performance rapid-setting hydrogel, which is recorded as H30.
[0048] Example 10: Preparation of high performance quick-setting hydrogel
[0049] The method of Example 1 was used with reference to that of Example 1, except that 15 g of deionized water was replaced by 35 g to prepare a hydrogel precursor solution, which was then gelled to obtain a high-performance rapid-setting hydrogel, which was designated as H35.
[0050] The following is a control sample preparation.
[0051] Comparative Example 1: Preparation of hydrogel without tetrahydroxydiboron addition
[0052] The method of Example 1 was used with reference to that of Example 1, except that 0.07 M THDB was replaced with 0 M to prepare a hydrogel, which was recorded as B0.
[0053] The beneficial effects of the present invention are demonstrated by experimental examples below.
[0054] Experimental Example 1: Testing the properties of hydrogel precursor solution and hydrogel
[0055] 1. Experimental methods
[0056] The properties of the hydrogel precursor solutions and hydrogels prepared in Examples 1 to 10 and Comparative Example 1 were tested.
[0057] (1) Determination of gelation time
[0058] The gelation time of hydrogel was tested by the Fisher method for determining the gelation time of epoxy resin matrix. 35 mL of the precursor solution containing initiator (i.e. the prepared hydrogel solution) was poured into a glass dish with a diameter of 9 cm. The time required for the precursor solution to reach the wire drawing state was measured with a glass rod, and this time was defined as the gelation time. All tests were carried out at 25°C. In order to make the gelation more intuitive, the vial inversion method was used for demonstration.
[0059] (2) Determination of mechanical properties
[0060] The tensile properties of the hydrogel were tested using an Instron 5567 universal testing machine (USA). The hydrogel samples were prepared in a dumbbell shape (length 20 mm, width 4 mm, thickness 1 mm). The stress-strain curve was obtained by stretching the sample at a speed of 100 mm / min until it broke.
[0061] (3) Determination of anti-swelling properties
[0062] The prepared dumbbell-shaped hydrogel samples were immersed in excess deionized water at 25°C, and the weight of the hydrogels immersed in deionized water was recorded at 0 h, 12 h, 1 d, 3 d, 5 d, 7 d, 15 d, 21 d, and 30 d. The swelling rate was calculated as follows: Swelling rate (g / g) = W t / W 0 ×100%(W t and W 0 are the weight of the sample at time t and the initial weight of the sample, respectively. )
[0063] 2. Experimental results
[0064] Figure 1 a and Figure 2 It shows that the gel time of hydrogel without THDB is longer. After being placed at 50°C for 5 to 6 hours, it is in a gelled state when inverted. The gel time of hydrogel with THDB is significantly shortened, and with the increase of THDB content in the system, the gel time of hydrogel is gradually shortened. When the content is 0.07M, the hydrogel can be gelled in about 15 minutes. Continuing to increase the amount of THDB has no obvious effect on the gel time. THDB provides the basis for its use as a soil stabilizer to achieve rapid free radical polymerization. Figure 1 be shows that there is a strong hydrogen bond interaction inside the hydrogel (B0.1) with THDB added, and its transparency is lower than that of the hydrogel (B0) without THDB added, and there is also phase separation inside. Figure 1 f shows that the mechanical properties of the hydrogel with THDB added (B0.1) are significantly improved compared with the hydrogel without THDB added (B0).
[0065] Since the water content in the hydrogel has a great influence on its anti-swelling performance, the initial water content of the hydrogel was changed to measure the anti-swelling performance. Figure 3 ) showed that the hydrogel with an initial water content of 10g would absorb more water through osmosis due to its low water content, causing the hydrogel structure to swell and have poor anti-swelling performance. However, other hydrogels showed excellent anti-swelling performance, with swelling rates less than 1.35g / g.
[0066] The present invention explores the effect of THDB content on the mechanical properties of hydrogel by regulating the THDB content in the system. The results show that when the THDB content of the hydrogel is 0.07M, the mechanical properties (stress, toughness and Young's modulus) of the hydrogel are the best ( Figure 4 a, b). This indicates that excessive THDB content will lead to dispersed hydrogel network density, stress concentration and reduced mechanical properties. At the same time, the results show that when the water content is 10g, the chemical crosslinking density will be significantly increased, thereby improving the mechanical properties of the hydrogel, and its stress, toughness and Young's modulus are the best ( Figure 4 c, d). However, when the water content was 10 g, the anti-swelling property of the hydrogel was poor and was not suitable for soil stabilization, so the hydrogel with a water content of 15 g was preferred for research.
[0067] In summary, the hydrogel soil stabilizer prepared by selecting 0.07M THDB content and 15g water content can quickly achieve gelation in a short time and has the best mechanical properties.
[0068] In summary, the present invention provides a high-performance quick-setting hydrogel soil stabilizer, a preparation method and use thereof. The present invention uses methacrylic acid, methacrylamide, and acrylamide as main raw materials, and introduces tetrahydroxydiboron and potassium persulfate to prepare a high-performance quick-setting hydrogel soil stabilizer. The hydrogel soil stabilizer has excellent mechanical properties and anti-swelling properties. The present invention can guide the rapid quantitative preparation of high-performance hydrogels in harsh environments, meet the stringent requirements of the field of soil stabilization on the curing time, permeability and high performance of hydrogels, and provide an effective solution strategy for the prevention and management of geological disasters.
Claims
1. A hydrogel precursor solution, characterized in that: It consists of acrylamide monomer, acrylic acid monomer, catalyst, initiator and water, wherein the acrylamide monomer is methacrylamide and acrylamide; the ratio of methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1-5M: 0-7M: 5-10M: 0-0.5M: 0.01-0.5M: 10-35ml.
2. The hydrogel precursor solution according to claim 1, characterized in that The ratio of the methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1.96M:5.63M:7.75M:0-0.5M:0.03M:10-35ml.
3. The hydrogel precursor solution according to claim 2, characterized in that: The ratio of the methacrylamide, acrylamide, acrylic acid monomer, catalyst and initiator is 1.96M:5.63M:7.75M:0.07M:0.03M:15ml.
4. The hydrogel precursor solution according to claim 1, characterized in that The acrylic acid monomer is methacrylic acid; the catalyst is a boron-containing hydroxyl compound; and the initiator is persulfate.
5. The hydrogel precursor solution according to claim 1, characterized in that: The acrylic acid monomer is methacrylic acid; the catalyst is tetrahydroxydiboron; and the initiator is potassium persulfate.
6. A method for preparing the hydrogel precursor solution according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: mixing methacrylamide, acrylic acid monomer, catalyst and water, and then adding acrylamide and initiator to obtain hydrogel.
7. A hydrogel, characterized in that: It is a product obtained by gelling the hydrogel precursor solution described in any one of claims 1 to 5.
8. A method for preparing the hydrogel according to claim 7, characterized in that: The method comprises the following steps: gelling a hydrogel precursor solution to obtain a hydrogel.
9. Use of the hydrogel precursor solution according to any one of claims 1 to 5 and the hydrogel according to claim 7 in the preparation of soil engineering materials.
10. The use according to claim 9, characterized in that The soil engineering material is a soil stabilizer.