Anti-seepage and anti-frost heaving material for water channel in cold region as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of anti-seepage and anti-frost-heaving materials, and relates to an anti-seepage and anti-frost-heaving material for a water channel in a cold region, a preparation method and application of the anti-seepage and anti-frost-heaving material. The component A comprises a prepolymer of aliphatic isocyanate and polyol, and a non-volatile diluent; the component B comprises an aliphatic chain extender, a latent curing agent, a pigment and an auxiliary agent; the volume ratio of the component A to the component B is (4-5): 1; the component A comprises the following components in parts by mass: 15-35 parts of aliphatic isocyanate, 50-80 parts of polyol and 5-15 parts of a non-volatile diluent; the component B comprises the following components in parts by mass: 40-80 parts of an aliphatic chain extender, 0-30 parts of a latent curing agent, 5-20 parts of a pigment and 2-6.5 parts of an auxiliary agent; the adhesive is solvent-free, environment-friendly, stable in curing speed, good in weather resistance, free of yellowing, free of embrittlement when bent at-40 DEG C and excellent in strength and impact resistance, and a bright and clean appearance can be obtained, and the adhesive can be quickly put into application.

Description

Technical Field

[0001] This invention belongs to the technical field of anti-seepage and anti-frost heave materials, specifically relating to an anti-seepage and anti-frost heave material for irrigation canals in cold regions, its preparation method, and its application. Background Technology

[0002] Seepage prevention in irrigation canals is crucial. Traditional methods typically involve reinforcing the bottom and slopes with gravel, followed by laying a layer of geotextile, then a waterproof membrane, then another layer of geotextile, and finally lining the geotextile with concrete, leaving gaps that are sealed with an elastic sealant. This approach is currently the primary method for solving canal reinforcement and seepage prevention problems.

[0003] However, in practical applications in cold regions, existing canal seepage prevention methods still cannot completely prevent significant water leakage, leading to a chain reaction of frost heave damage to the concrete, causing cracking and collapse of the concrete layer. There is also the risk of concrete weathering and freezing damage after water seepage. The main reasons for these problems are twofold: First, problems with the geomembrane waterproofing. During geomembrane construction, numerous joints require welding; if the welding is not strong or precise, leakage will occur. Damage to the waterproofing layer can also occur during concrete laying. Leakage combined with freezing causes the foundation to expand, leading to structural damage. Secondly, the surface lining concrete itself absorbs water and will expand and fail if it freezes. Finally, when the foundation experiences significant settlement, cracking of the concrete structure is inevitable.

[0004] Existing waterproofing materials cannot meet the diverse practical application requirements, including high strength, impact and abrasion resistance, puncture resistance, aging resistance, low-temperature resistance, excellent elasticity, and stone impact resistance. For example, while the material in invention CN109593460A can cure quickly and improve efficiency, it uses an aromatic system, especially since the chain extenders are also aromatic, leading to discoloration and unsatisfactory weather resistance. The material in invention CN110630452A also belongs to an aromatic system, causing discoloration during application, and its weather resistance cannot meet the high weather resistance requirements of cold, high-sunlight regions. Furthermore, this invention is a solvent-based coating, which is not environmentally friendly, and in practical applications, it cannot meet the needs of rapid on-site construction and application to achieve the required thickness. The material in invention CN109593460A is a single-component solvent-based material, used in the field of automotive synthetic leather. It contains solvents, making it insufficiently environmentally friendly, and it cannot achieve the requirements of solvent-free rapid construction and curing, requiring multiple applications to achieve the required thickness. Solvent-based coatings require multiple coats to achieve the required thickness, which is inefficient and cannot meet the requirements for rapid reaction. Furthermore, they tend to run and have an unsatisfactory appearance if the coating is applied too thickly. In addition, the presence of solvents makes them less environmentally friendly.

[0005] Therefore, a high-performance waterproofing material is needed that can meet the requirements of low temperature resistance, impact resistance, rapid thickness achievement, rapid application, good weather resistance, beautiful appearance, environmental protection, excellent elasticity, excellent waterproofing effect, and impact and abrasion resistance, while also ensuring excellent interlayer bonding during construction to solve the above technical problems. Summary of the Invention

[0006] The present invention provides the following technical solution: a seepage-proof and frost-resistant material for irrigation canals in cold regions, comprising: component A and component B; component A comprises: aliphatic isocyanate, polyol, and non-volatile diluent; component B comprises: aliphatic chain extender, latent curing agent, pigment, and additives; the volume ratio of component A to component B is 4 to 5:1.

[0007] Component A comprises the following components in parts by weight: 15-35 parts aliphatic isocyanate, 50-80 parts polyol, and 5-15 parts non-volatile diluent; Component B comprises the following components in parts by weight: 40-80 parts aliphatic chain extender, 0-30 parts latent curing agent, 5-20 parts pigment, and 2-6.5 parts additives.

[0008] The additives include the following components in parts by weight: 1-3 parts antioxidant, 1-3 parts light stabilizer, 0.05-0.1 parts leveling agent, and 0-0.3 parts hydrolysis accelerator.

[0009] Preferably, component A comprises the following components in parts by weight: 20-30 parts aliphatic isocyanate, 58-67 parts polyol, and 9-15 parts non-volatile diluent; component B comprises the following components in parts by weight: 55-80 parts aliphatic chain extender, 20-30 parts latent curing agent, 5.65-17 parts pigment, and 2.35-6.1 parts additives.

[0010] Preferably, the aliphatic isocyanate includes one or more of isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated diphenylmethylene diisocyanate.

[0011] Preferably, the polyol includes one or more of hydroxyl-terminated hydrogenated polybutadiene and polytetrahydrofuran ether diol; the non-volatile diluent includes one or more of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate and diisopropylnaphthalene.

[0012] More preferably, the hydroxyl-terminated hydrogenated polybutadiene has a molecular weight of 1500-2000 and a hydroxyl value of 40-75; the polytetrahydrofuran ether diol has a molecular weight of 1000-2000.

[0013] Preferably, the aliphatic chain extender includes one or more of isophorone diamine modifier and 4,4′-bis(sec-butylamino)-dicyclohexylmethane; the latent curing agent is carbamate diazonil.

[0014] More preferably, the antioxidant is octadecanoate of 3,5-di-tert-butyl-4-hydroxyphenylpropionate; the light stabilizer is Tinuvin B75; the leveling agent is Tego Glide 410; and the hydrolysis accelerator is salicylic acid.

[0015] This invention also discloses a method for preparing a seepage-proof and frost-resistant material for irrigation canals in cold regions. This method comprises the following steps: Preparation of component A: Add the polyol to the reactor and dehydrate it under reduced pressure at 100-120°C for 0.5-1.5 hours. Then cool it down to 55-65°C and add the aliphatic isocyanate. After the reaction, heat it up to 85-95°C and keep it at that temperature for 3-3.5 hours. Then add the non-volatile diluent. When the free NCO content reaches 5%-6%, cool it down and filter it to discharge the material.

[0016] Preparation of component B: The aliphatic chain extender is dehydrated under reduced pressure at 100–120°C for 0.5–1.5 hours, and then cooled to 55–65°C for later use.

[0017] Aliphatic chain extenders, latent curing agents, pigments, and additives are ground in a sand mill. When the fineness reaches 60μm, the material is filtered out.

[0018] Mix component A and component B according to the usage ratio.

[0019] The present invention also discloses the application of a seepage-proof and frost-resistant material for irrigation canals in cold regions. The application uses the above-mentioned seepage-proof and frost-resistant material, which is used to reinforce, strengthen, prevent seepage, and resist frost at the bottom and / or slope of the irrigation canal.

[0020] Preferably, the implementation steps of the application include: Step 1: Level and compact the bottom and slopes of the canal with gravel; after the canal foundation is stable, before laying the geotextile, reserve a space for a cast-in-place concrete partition wall at intervals in the Gobi cushion foundation.

[0021] Step 2: Lay geotextile on the gravel cushion layer. The standard for laying geotextile is not less than 500 grams per square meter, and geotextile with short pile should be selected.

[0022] Step 3: Apply a waterproof and frost-resistant material to the geotextile joints for rapid bonding, with an overlap width of not less than 10cm.

[0023] Step 4: Then, spray the entire geotextile with an anti-seepage and anti-frost heave material, with a spray thickness of not less than 1.5mm.

[0024] Step 5: Leave a margin for both the geotextile and the sprayed impermeable and frost-resistant material to prevent stretching caused by substrate settlement.

[0025] Step 6: After the anti-seepage and anti-frost heave material is sprayed, pour concrete on the surface of the cast-in-place concrete partition wall; increase the thickness of the anti-seepage and anti-frost heave material sprayed under and on both sides of the poured concrete.

[0026] Step 7: At the original capping plate position at the top of the channel, the geotextile is vertically folded down along the outer edge of the top and then laid horizontally outward before backfilling with sand and gravel to stabilize the top edge of the channel.

[0027] The beneficial effects of this invention are: 1. The waterproof system of the anti-seepage and anti-frost heave material of this invention is integrally formed without seams, making the anti-seepage effect more reliable and the underground foundation less prone to frost heave.

[0028] 2. The elongation of the anti-seepage and anti-frost heave material of this invention can reach more than 450%, and it does not crack when subjected to tensile and fatigue deformation, and can adapt well to the deformation of the substrate.

[0029] 3. The anti-seepage and anti-frost heave material of this invention has high wear resistance, and its anti-abrasion performance is more than 10 times that of concrete, and it can withstand long-term erosion by water flow.

[0030] 4. The anti-seepage and anti-freeze-heave material of this invention has excellent low-temperature resistance. It does not become brittle at -40℃, maintains its elasticity, and is not prone to cracking in winter.

[0031] 5. The anti-seepage and anti-freeze-heave material of this invention is environmentally friendly and non-toxic, meeting the relevant requirements for application in the drinking water field.

[0032] 6. The anti-seepage and anti-frost heave material of this invention can effectively prevent damage caused by frost heave, settlement, freezing and other issues when the original concrete is used as a covering layer.

[0033] 7. The waterproof and frost-resistant material of this invention has high weather resistance and a long service life.

[0034] 8. The anti-seepage and anti-frost heave material of this invention has a low overall cost and high cost performance. Attached Figure Description

[0035] Figure 1 This is a schematic cross-sectional view of the spraying application of a seepage-proof and frost-resistant material for irrigation canals in cold regions according to the present invention. Detailed Implementation

[0036] The related technologies of the present invention will be clearly and completely described below with reference to the accompanying drawings of 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.

[0037] The material used in this embodiment is a solvent-free polyurethane spraying material, consisting of two components, A and B. Component A is composed of a prepolymer of one, two, or three aliphatic isocyanates selected from isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated dimethyl phthalate, along with a polyol and a non-volatile diluent. Component B consists of an aliphatic chain extender, a latent curing agent, additives, and pigments.

[0038] The material is solvent-free and environmentally friendly; it has a stable curing speed, which can achieve a smooth appearance and be quickly put into application; it has good weather resistance and does not yellow; it has good low temperature resistance and does not crack when bent at -40℃; it also has excellent strength and impact resistance.

[0039] The AB material formulation of this invention is as follows: volume ratio: component A: component B = 4:1 to 5:1 The composition of component A, by mass parts: The composition includes: 15-35 parts aliphatic isocyanate, 50-80 parts polyol, and 5-15 parts non-volatile diluent. The isocyanate includes one, two, or three aliphatic isocyanates selected from isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated dimethyl phthalate diisocyanate. The polyol in component A is one or two selected from hydroxyl-terminated hydrogenated polybutadiene with excellent low-temperature resistance and polytetrahydrofuran ether diol with good low-temperature resistance and high strength. The hydroxyl-terminated hydrogenated polybutadiene has a molecular weight of 1500-2000 and a hydroxyl value of 40-75. The polytetrahydrofuran ether polyol has a molecular weight of 1000-2000; considering the viscosity and workability of the prepolymer, a molecular weight of 1000 is preferred. The non-volatile diluents are environmentally friendly and non-toxic 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB) and environmentally friendly, non-toxic, and odorless diisopropylnaphthalene (DI). One or both can be selected and used in combination. The main purpose of adding non-volatile diluents is to reduce viscosity and improve ease of application.

[0040] The composition of component B, by mass parts: The mixture includes: 40-80 parts of aliphatic chain extender, 0-30 parts of latent curing agent, 5-20 parts of pigment, and 2-6.5 parts of additives. The additives, by weight, consist of 1-3 parts of antioxidant, 1-3 parts of light stabilizer, 0.05-0.1 parts of leveling agent, and 0-0.3 parts of hydrolysis accelerator. The aliphatic chain extender includes one or both of isophorone diamine modifier and 4,4′-bis(sec-butylamino)-dicyclohexylmethane. For the isophorone diamine modifier, BASFPC136 is selected, as its reactivity is significantly lower than that of isophorone diamine, resulting in a stable reaction and easier attainment of a smooth coating appearance and good interlayer adhesion. The latent curing agent is a carbamate diazonil, preferably Covestro VP LS2142, which is more conducive to obtaining high-strength materials and also helps to adjust the overall curing speed, achieving good interlayer adhesion and a smooth surface. Different weather-resistant pigments of various colors are selected as needed. The antioxidant used is octadecanoate 3,5-di-tert-butyl-4-hydroxyphenylpropionate, CAS No. 2082-79-3, also known as antioxidant 1076. The light stabilizer used is Tinuvin B75, a product of Ciba Specialty Chemicals, Switzerland. The leveling agent used is Tego Glide 410. The hydrolysis accelerator used is salicylic acid, which promotes the hydrolysis of the latent curing agent.

[0041] Example 1, Preparation scheme 1 for anti-seepage and anti-frost heave material: Preparation of component A: Take 26 parts by weight of hydroxyl-terminated hydrogenated polybutadiene (molecular weight 1500, hydroxyl value 70) and 39 parts by weight of polytetrahydrofuran ether glycol (molecular weight 1000, hydroxyl value 112), add them to the reactor, dehydrate under reduced pressure at 100℃ for 1 hour, then cool down to 60℃, and slowly add 26 parts of isophorone diisocyanate. After reacting for half an hour, slowly raise the temperature to 90℃ and keep it at that temperature for 3 hours. Then add 9 parts of diisopropylnaphthalene (DI). When the free NCO content reaches 5.19±0.1%, cool down and filter to discharge the material.

[0042] Preparation of component B: The weather-resistant titanium dioxide was baked at 110℃ for 4 hours to remove water, and then set aside.

[0043] The aliphatic chain extender PC136 was dehydrated under reduced pressure at 100°C for 1 hour, and then cooled to 60°C for later use.

[0044] By weight, 60 parts of chain extender PC136, 20 parts of latent curing agent VP LS 2142, 15.7 parts of titanium dioxide, 0.1 parts of leveling agent Glide 410, 2 parts of antioxidant 1076, 2 parts of light stabilizer Tinuvin B75, and 0.2 parts of salicylic acid were put into a sand mill and ground. When the fineness reached 60μm, the material was filtered out.

[0045] Use the following mixing ratio: Volume ratio A:B = 5:1 Example 2, Preparation scheme 2 for anti-seepage and anti-frost heave material: Preparation of component A: Take 30 parts by weight of hydroxyl-terminated hydrogenated polybutadiene (molecular weight 1500, hydroxyl value 70) and 28 parts by weight of polytetrahydrofuran ether glycol (molecular weight 1000, hydroxyl value 112), add them to the reactor, dehydrate under reduced pressure at 110℃ for 1 hour, then cool down to 60℃, and slowly add 30 parts of dicyclohexylmethane diisocyanate (HMDI). After reacting for half an hour, slowly raise the temperature to 90℃ and keep it at that temperature for 3 hours. Then add 12 parts of diisopropylnaphthalene (DI). When the free NCO content reaches 5.69±0.1%, cool down and filter to discharge the material.

[0046] Preparation of component B: The weather-resistant Hansa Yellow pigment was baked at 115℃ for 4 hours to remove water, and then set aside.

[0047] The aliphatic chain extender 4,4′-bis(sec-butylamino)-dicyclohexylmethane (HMDBA) was dehydrated under reduced pressure at 110°C for 1 hour, and then cooled to 60°C for later use.

[0048] By weight, 55 parts of chain extender HMDBA, 28 parts of latent curing agent VP LS 2142, 13 parts of Hansa Yellow pigment, 0.1 parts of leveling agent Glide 410, 1.8 parts of antioxidant 1076, 1.8 parts of light stabilizer Tinuvin B75, and 0.3 parts of salicylic acid were put into a sand mill and ground. When the fineness reached 60μm, the material was filtered out.

[0049] Use the following mixing ratio: A:B volume ratio 4:1 Example 3, Preparation scheme 3 for anti-seepage and anti-frost heave material: Preparation of component A: Take 20 parts by weight of hydroxyl-terminated hydrogenated polybutadiene (molecular weight 1500, hydroxyl value 70) and 40.8 parts by weight of polytetrahydrofuran ether glycol (molecular weight 1000, hydroxyl value 112), and put them into a reactor. Dehydrate under reduced pressure at 110℃ for 1 hour, then cool down to 60℃, and slowly add 24.2 parts of hydrogenated dimethyl phthalate (HXDI). After reacting for half an hour, slowly raise the temperature to 90℃ and keep it at that temperature for 3 hours. Then add 15 parts of TXIB. When the free NCO content reaches 6.0±0.1%, cool down and filter to discharge the material.

[0050] Preparation of component B: The aliphatic chain extender PC136 was dehydrated under reduced pressure at 110°C for 1 hour, and then cooled to 60°C for later use.

[0051] By weight, 62 parts of chain extender PC136, 30 parts of latent curing agent VP LS 2142, 5.65 parts of carbon black pigment, 0.05 parts of leveling agent Glide 410, 1 part of antioxidant 1076, 1 part of light stabilizer Tinuvin B75, and 0.3 parts of salicylic acid were put into a sand mill and ground. When the fineness reached 60μm, the material was filtered out.

[0052] Use the following mixing ratio: Volume ratio A:B = 5:1 Example 4, Preparation scheme 4 for anti-seepage and anti-frost heave material: Preparation of component A: Take 67 parts by weight of hydroxyl-terminated hydrogenated polybutadiene (molecular weight 2000, hydroxyl value 50), add it to the reactor, dehydrate it under reduced pressure at 110℃ for 1 hour, then cool it down to 60℃, and slowly add 20 parts of isophorone diisocyanate (IPDI). After reacting for half an hour, slowly raise the temperature to 90℃ and keep it at that temperature for 3 hours. Then add 13 parts of diisopropylnaphthalene (DI). When the free NCO content reaches 5.0±0.1%, cool it down, filter it and discharge it.

[0053] Preparation of component B: The weather-resistant Hansa Yellow pigment was baked at 115℃ for 4 hours to remove water, and then set aside.

[0054] The aliphatic chain extender 4,4′-bis(sec-butylamino)-dicyclohexylmethane (HMDBA) and the chain extender PC136 were dehydrated under reduced pressure at 110°C for 1 hour, and then cooled to 60°C for later use.

[0055] By weight, 15 parts of chain extender HMDBA, 44 parts of chain extender PC136, 20 parts of latent curing agent VP LS 2142, 17 parts of Hansa Yellow pigment, 0.1 parts of leveling agent Glide 410, 1.8 parts of antioxidant 1076, 1.8 parts of light stabilizer Tinuvin B75, and 0.3 parts of salicylic acid were put into a sand mill and ground. When the fineness reached 60μm, the material was filtered out.

[0056] Mixing ratio: A:B volume ratio 5:1 Example 5, Preparation scheme 5 for anti-seepage and anti-frost heave material: Preparation of component A: Take 61 parts by weight of polytetrahydrofuran ether diol (molecular weight 1000, hydroxyl value 112), add it to the reactor, dehydrate it under reduced pressure at 120℃ for 1 hour, then cool it down to 60℃, and slowly add 24 parts of hydrogenated dimethyl phthalate (HXDI). After reacting for half an hour, slowly raise the temperature to 90℃ and keep it at that temperature for 3 hours. Then add 15 parts of diisopropylnaphthalene (DI). When the free NCO content reaches 5.2±0.1%, cool it down and filter it to discharge the material.

[0057] Preparation of component B: The weather-resistant permanent red pigment was baked at 120℃ for 4 hours to remove water, and then set aside.

[0058] The aliphatic chain extender PC136 was dehydrated under reduced pressure at 120°C for 1 hour, and then cooled to 60°C for later use.

[0059] By weight, 80 parts of chain extender PC136, 13.9 parts of permanent red pigment, 0.1 parts of leveling agent Glide 410, 3 parts of antioxidant 1076, and 3 parts of light stabilizer Tinuvin B75 were put into a sand mill for grinding. When the fineness reached 60μm, the material was filtered out.

[0060] Use the following ratio: A:B volume ratio 5:1.

[0061] The performance of Examples 1-5 is shown in Table 1, and the performance tests of Examples are based on the standards shown in Table 2.

[0062] The formulas in this invention and the corresponding technical effects produced by them have the following relationship: 1. The material in the embodiments of the present invention has good weather resistance, does not yellow, and is not easily powdered.

[0063] This invention utilizes aliphatic materials, which exhibit significantly higher weather resistance and aging resistance compared to traditional aromatic polyurethanes and polyureas. For example, this invention employs aliphatic isocyanates: isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated diphenylmethylene diisocyanate, while simultaneously using aliphatic chain extenders: 4,4′-bis(sec-butylamino)-dicyclohexylmethane (HMDBA) and chain extender PC136 to ensure high weather resistance. Traditional aromatic polyurethanes quickly discolor and chalk.

[0064] 2. Another advantage of this invention is its resistance to low temperatures and high elongation.

[0065] This invention utilizes a low-NCO content prepolymer and chain extender reaction, with the prepolymer containing 5%–6% NCO. The resulting product exhibits better low-temperature resistance, higher elongation, and greater flexibility. In other words, the lower the NCO content, the softer the material, the better its low-temperature resistance, and the higher its elongation. However, too low a content negatively impacts strength; therefore, an optimal balance needs to be struck.

[0066] 3. The present invention has good low-temperature resistance and wear resistance.

[0067] The present invention mainly uses hydroxyl-terminated polybutadiene and polytetrahydrofuran ether polyol, which have better low-temperature resistance, and polytetrahydrofuran ether polyol has better wear resistance.

[0068] 4. If the aliphatic amino chain extender 4,4′-bis(sec-butylamino)-dicyclohexylmethane (HMDBA) is used, the reaction rate is very fast, curing in just a few seconds, resulting in an unattractive surface finish and poor wettability and leveling. To moderate the reaction rate, this invention uses the slower-reacting chain extender PC136, along with the high-strength latent curing agent VP LS 2142. VP LS 2142 releases ammonia upon contact with moisture in the air after material spraying, and then rapidly reacts with the isocyanate. Therefore, the reaction rate of VP LS 2142 is even slower than that of the chain extender PC136 used in this solution.

[0069] In the embodiments of the present invention, the higher the NCO content, the higher the strength of the material, but the elongation will decrease and the low-temperature resistance will deteriorate. The polyurethane prepolymer in Example 3 has the highest NCO content, at 6%, so it has the highest tensile strength. Of course, a high NCO content does not necessarily mean high strength; it also depends on the raw materials used and the type of chain extender in component B. The five embodiments of the present invention verify the different effects of different schemes. In practical applications, different balance points can be selected and different technical solutions can be adopted according to different needs.

[0070] Application examples like Figure 1 As shown, the construction plan for the irrigation canal is as follows: This application example was formed using the following method: spraying with a spraying machine. The spraying machine used was a variable ratio airless sprayer DF-YB30 / 32. The material used for spraying was the impermeable and frost-resistant material prepared in Example 1.

[0071] Temperature settings for the spraying equipment: Set component A to 70℃, component B to 60℃, pipeline temperature to 65℃, and spraying pressure to 2000-2500 psi. Fix heating belts to the outside of the A and B material containers to reduce viscosity, heating the materials inside to 50-75℃. Stir component B before use. Practice has shown that if the material sprayed onto geotextile reacts too quickly, many burrs will form on the surface, resulting in poor leveling and wetting. Therefore, the material reaction rate needs to be appropriately slow to ensure a dense coating.

[0072] The construction steps are as follows: 1. Level and compact the bottom and side slopes of the existing excavated canal with gravel, ensuring there are no sharp protrusions.

[0073] 2. Lay geotextile on the gravel cushion layer. Polyester-reinforced geotextile is preferred. The standard for geotextile is not less than 500 grams per square meter, and geotextile with short pile should be selected.

[0074] 3. The geotextile joints shall be quickly bonded with impermeable and frost-resistant materials, with an overlap width of not less than 10cm.

[0075] 4. Finally, apply a waterproof and anti-freeze-heave material to the entire surface. The thickness of the waterproof material should be no less than 1.5mm, and 1.5-2mm is recommended.

[0076] 5. Allow for a margin in geotextiles and sprayed impermeable and frost-resistant materials to prevent stretching caused by substrate settlement.

[0077] 6. After the channel foundation is stabilized, before laying the geotextile, reserve a 30cm wide and 20cm thick cast-in-place concrete partition wall every 50 meters in the Gobi cushion foundation. After the surface of the anti-seepage and anti-frost heave material is sprayed, pour the concrete. The thickness of the anti-seepage and anti-frost heave material sprayed under the poured concrete and on both sides should be appropriately increased, and it can be sprayed with a width of 50cm and a thickness of 2.5mm.

[0078] 7. For the original capping plate at the top of the channel, the geotextile can be vertically folded down 20cm along the outer edge of the top, then horizontally laid out 30cm of geotextile, and then backfilled with 30cm of gravel for spraying anti-seepage and anti-frost heave material to stabilize the top edge of the channel.

[0079] In summary, the waterproof system implemented with the anti-seepage and anti-frost heave material of this invention is integrally formed without seams, resulting in more reliable seepage prevention and making underground foundations less prone to frost heave. Therefore, this invention has broad application prospects in the field of polyurethane elastomer low-temperature resistant, weather-resistant, and impact-resistant anti-seepage materials.

[0080] It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A seepage-proof and frost-resistant material for irrigation canals in cold regions, characterized in that, include: Component A and Component B; Component A comprises: aliphatic isocyanate, polyol, and non-volatile diluent; Component B comprises: aliphatic chain extender, latent curing agent, pigment, and additives; the volume ratio of component A to component B is 4-5:

1. Component A comprises the following components in parts by weight: 15-35 parts aliphatic isocyanate, 50-80 parts polyol, and 5-15 parts non-volatile diluent; Component B comprises the following components in parts by weight: 40-80 parts aliphatic chain extender, 0-30 parts latent curing agent, 5-20 parts pigment, and 2-6.5 parts additives; The additives comprise the following components in parts by weight: 1-3 parts antioxidant, 1-3 parts light stabilizer, 0.05-0.1 parts leveling agent, and 0-0.3 parts hydrolysis accelerator.

2. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 1, characterized in that, Component A comprises the following components in parts by weight: 20-30 parts aliphatic isocyanate, 58-67 parts polyol, and 9-15 parts non-volatile diluent; Component B comprises the following components in parts by weight: 55-80 parts aliphatic chain extender, 20-30 parts latent curing agent, 5.65-17 parts pigment, and 2.35-6.1 parts additives.

3. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 1, characterized in that, The aliphatic isocyanate includes one or more of isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated diphenylmethylene diisocyanate.

4. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 1, characterized in that, The polyol includes one or more of hydroxyl-terminated hydrogenated polybutadiene and polytetrahydrofuran ether diol; The non-volatile diluent includes one or more of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate and diisopropylnaphthalene.

5. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 4, characterized in that, The hydroxyl-terminated hydrogenated polybutadiene has a molecular weight of 1500-2000 and a hydroxyl value of 40-75; the polytetrahydrofuran ether diol has a molecular weight of 1000-2000.

6. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 1, characterized in that, The aliphatic chain extender includes one or more of isophorone diamine modifier and 4,4′-bis(sec-butylamino)-dicyclohexylmethane; The latent curing agent is carbamate diazonil.

7. The seepage-proof and frost-resistant material for irrigation canals in cold regions according to claim 1, characterized in that, The antioxidant is octadecanoate of 3,5-di-tert-butyl-4-hydroxyphenylpropionate; The light stabilizer is Tinuvin B75; The leveling agent is Tego Glide 410; The hydrolysis accelerator is salicylic acid.

8. A method for preparing a seepage-proof and frost-heave-resistant material for irrigation canals in cold regions, characterized in that, The preparation method is used to prepare the impermeable and frost-resistant material according to any one of claims 1 to 7, and the preparation method includes the following steps: Preparation of component A: Add polyol to a reaction vessel and dehydrate under reduced pressure at 100-120°C for 0.5-1.5 hours. Then cool down to 55-65°C and add aliphatic isocyanate. After reaction, heat up to 85-95°C and keep warm for 3-3.5 hours. Then add non-volatile diluent. When the free NCO content reaches 5%-6%, cool down and filter to discharge the material. Preparation of component B: The aliphatic chain extender is dehydrated under reduced pressure at 100–120°C for 0.5–1.5 hours, and then cooled to 55–65°C for later use. Aliphatic chain extenders, latent curing agents, pigments, and additives are put into a sand mill and ground. When the fineness reaches 60μm, the material is filtered out. Mix component A and component B according to the usage ratio.

9. The application of a seepage-proof and frost-heave-resistant material for irrigation canals in cold regions, characterized in that, The application uses the seepage-proof and frost-resistant material as described in any one of claims 1 to 7, which is used for the reinforcement, strengthening, seepage prevention, and frost resistance of the bottom of the canal and / or the slope.

10. The application of the seepage-proof and frost-heave-resistant material for irrigation canals in cold regions according to claim 9, characterized in that, The implementation steps of the application include: Step 1: Level and compact the bottom and side slopes of the canal with gravel; after the canal foundation is stable, before laying the geotextile, reserve a space for a cast-in-place concrete partition wall at intervals in the Gobi cushion foundation. Step 2: Lay geotextile on the gravel cushion layer. The standard for laying geotextile is not less than 500 grams per square meter, and geotextile with short pile should be selected. Step 3: Apply a waterproof and frost-resistant material to the geotextile joints for rapid bonding, with an overlap width of not less than 10cm; Step 4: Then, spray the entire geotextile with an anti-seepage and anti-frost heave material, with a spray thickness of not less than 1.5mm; Step 5: Leave a margin for both the geotextile and the sprayed impermeable and frost-resistant material to prevent stretching caused by substrate settlement; Step 6: After the anti-seepage and anti-frost heave material is sprayed, pour concrete on the surface of the cast-in-place concrete partition wall; increase the thickness of the anti-seepage and anti-frost heave material sprayed under and on both sides of the poured concrete. Step 7: At the original capping plate position at the top of the channel, the geotextile is vertically folded down along the outer edge of the top and then laid horizontally outward before backfilling with sand and gravel to stabilize the top edge of the channel.

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