Waterborne polyurethane capsule, abrasion-resistant concrete and preparation method of abrasion-resistant concrete

Abstract

The invention discloses a waterborne polyurethane capsule, abrasion-resistant concrete and a preparation method of the abrasion-resistant concrete, and the waterborne polyurethane capsule is prepared from the following components in parts by weight: 60 to 100 parts of polyvinyl alcohol aqueous solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose and 1200 to 1400 parts of waterborne polyurethane. The abrasion-resistant concrete is prepared from 42.5 high-heat cement, aggregate, water, a waterborne polyurethane capsule finished product and an additive, wherein the mass ratio of the 42.5 high-heat cement to the aggregate to the water to the waterborne polyurethane capsule finished product to the additive is (383.84 to 400) to (1818.18) to (171.72) to (19.19 to 20) to 1; the preparation method of the waterborne polyurethane capsule is simple and low in cost; according to the preparation method of the anti-abrasion concrete, the polyurethane can be uniformly dispersed, and the compressive strength and the anti-abrasion strength of the concrete are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of concrete, and specifically relates to waterborne polyurethane capsules, a preparation method of the waterborne polyurethane capsules, abrasion-resistant concrete, and a preparation method of the abrasion-resistant concrete. Background Art

[0002] Hydraulic channels are channels specifically designed to guide, control, or regulate water flow in water conservancy projects. According to different functions and water flow directions, hydraulic channels can be divided into various types. As a key material in hydraulic structures, the flow channel concrete needs to have high compressive strength and abrasion-resistant strength to ensure that it can withstand the pressure and impact force generated by water flow. At the same time, it also needs to have good frost resistance, durability, and corrosion resistance to ensure the safety and efficient operation of water conservancy projects.

[0003] Waterborne polyurethane is a material with excellent properties. By combining it with cement, the performance of cement-based materials can be significantly improved. Such as enhancing the bond strength, reducing brittleness, improving durability, improving mechanical properties and microstructures, and reducing surface permeability, etc. Waterborne polyurethane cement not only improves its mechanical properties and durability by modifying traditional cement, but also reduces brittleness and surface permeability, making it have a wider application prospect in construction engineering. Therefore, polyurethane concrete is an effective method to solve concrete deterioration and improve durability. In the existing preparation process of polyurethane concrete, polyurethane is directly added, but polyurethane is prone to agglomeration and uneven distribution in concrete, resulting in unstable quality of polyurethane concrete. Currently, by adding polyurethane capsules to concrete, when the hydration reaction causes the outer wall of the capsule to rupture, the internal waterborne polyurethane is released, which can solve the problem of easy agglomeration of polyurethane.

[0004] Existing preparation methods of polyurethane capsules include interfacial polymerization method, in-situ polymerization method, solvent evaporation method, spray drying method, etc. The above methods all need to prepare the core material first and then coat the outer shell on the surface of the core material, which has the problems of complex process and high preparation cost. Summary of the Invention

[0005] The first object of the present invention is to provide waterborne polyurethane capsules to solve the problem of high preparation cost of existing polyurethane capsules.

[0006] The second object of the present invention is to provide a preparation method of the waterborne polyurethane capsules.

[0007] The third object of the present invention is to provide abrasion-resistant concrete to solve the problem of uneven dispersion of polyurethane in existing polyurethane concrete.

[0008] The fourth object of the present invention is to provide a preparation method of the abrasion-resistant concrete.

[0009] The first technical solution adopted by the present invention is an aqueous polyurethane capsule, which is composed of the following components in parts by weight: 60 to 100 parts of an aqueous polyvinyl alcohol solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of aqueous polyurethane.

[0010] The characteristics of the present invention also lie in: The aqueous polyvinyl alcohol solution is formed by mixing polyvinyl alcohol particles, water, and an auxiliary agent. The mass ratio of polyvinyl alcohol particles: water: auxiliary agent is 5 to 15: 85 to 95: 0.1 to 1.5; The degree of polymerization of the polyvinyl alcohol particles is 500 to 2400, and the degree of alcoholysis is 87% to 89%.

[0011] The second technical solution adopted by the present invention is a preparation method of an aqueous polyurethane capsule, which is specifically implemented according to the following steps: Step 1, weigh the following raw materials in parts by weight: 60 to 100 parts of an aqueous polyvinyl alcohol solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of aqueous polyurethane; Step 2, after uniformly mixing the weighed aqueous polyvinyl alcohol solution, starch, glycerol, and glucose, apply them to a stainless steel conveyor belt, and stop applying when the thickness reaches the preset thickness to obtain a wet outer shell material; Step 3, remove the wet outer shell material from the stainless steel conveyor belt and place it into an outer shell mold and a partition mold respectively to prepare a capsule outer shell and a closed partition; Step 4, paste the open ends of the two capsule outer shells on both sides of the closed partition respectively, and obtain a spherical polyvinyl alcohol capsule outer shell after heat treatment; Step 5, inject aqueous polyurethane into the spherical polyvinyl alcohol capsule outer shell through an injection port, and seal the injection port after injection to obtain a finished product of the aqueous polyurethane capsule.

[0012] The characteristics of the present invention also lie in: The aqueous polyvinyl alcohol solution is formed by mixing polyvinyl alcohol particles, water, and an auxiliary agent. The mass ratio of polyvinyl alcohol particles: water: auxiliary agent is 5 to 15: 85 to 95: 0.1 to 1.5; the degree of polymerization of the polyvinyl alcohol particles is 500 to 2400, and the degree of alcoholysis is 87% to 89%.

[0013] The outer shell mold includes a bottom plate, on which a magnetic suction hemispherical base is arranged. A hemispherical cover plate is sleeved on the outer wall of the magnetic suction hemispherical base. The hemispherical cover plate is concentric with the magnetic suction hemispherical base. A cylindrical cutting knife is inserted at the midpoint of the hemispherical cover plate. A protrusion is arranged on the outer wall of the hemispherical cover plate and close to the bottom plate. The protrusion is connected to the upper surface of the bottom plate through a double-ear seat; The partition die includes a cutting bottom plate and a movable plate. Load-bearing columns are provided at the four corners of the cutting bottom plate. Sliding tracks are provided on the opposite side walls of two load-bearing columns located on the same side, and sliding tracks are also provided on the opposite side walls of the other two load-bearing columns located on the same side. A slider is arranged in each sliding track, and the four sliders are respectively arranged on the two side walls of the movable plate. A number of cutting tools arranged in a matrix are provided on the lower surface of the movable plate. A through hole A is provided at one end of each load-bearing column and sliding track away from the cutting bottom plate, a through hole B is provided on each slider, and a pin is inserted into each through hole A and its corresponding through hole B.

[0014] In step 4, the heat treatment temperature is 60°C to 80°C, and the time is 10 min to 30 min.

[0015] The third technical solution adopted by the present invention is that the impact-resistant and abrasion-resistant concrete is composed of forty-two point five high-heat cement, aggregate, water, finished waterborne polyurethane capsules and admixtures. The mass ratio of forty-two point five high-heat cement, aggregate, water, finished waterborne polyurethane capsules and admixtures is 383.84 - 400:1818.18:171.72:19.19 - 20:1; The finished waterborne polyurethane capsules are prepared by the preparation method of the above-mentioned waterborne polyurethane capsules.

[0016] The characteristics of the present invention also lie in: The aggregate is composed of sand and crushed stone, and the mass ratio of sand to crushed stone is 1:1.5; The admixture is composed of a water reducer, an air-entraining agent and a retarder, and the mass ratio of the water reducer, the air-entraining agent and the retarder is 19:1:4.75.

[0017] The fourth technical solution adopted by the present invention is a preparation method of impact-resistant and abrasion-resistant concrete, which is specifically implemented according to the following steps: Step 1, weigh the raw materials according to the mass ratio: the mass ratio of forty-two point five high-heat cement, aggregate, water, finished waterborne polyurethane capsules and admixtures is 383.84 - 400:1818.18:171.72:19.19 - 20:1; The finished waterborne polyurethane capsules are prepared by the preparation method of the above-mentioned waterborne polyurethane capsules; Step 2, add forty-two point five high-heat cement, aggregate, water and admixtures into a mixer and stir well to obtain a mixture. When the temperature of the mixture reaches 30°C - 35°C, add the finished waterborne polyurethane capsules and continue to stir until the capsule shell of the finished waterborne polyurethane capsules is completely hydrated and dissolved to obtain the impact-resistant and abrasion-resistant concrete.

[0018] The characteristics of the present invention also lie in: The mixer includes a mixing drum, with a motor installed at the top of the mixing drum. The output shaft of the motor is connected to one end of a mixing rod, and the other end of the mixing rod extends into the interior of the mixing drum. The other end of the mixing rod is connected to the open ends of multiple U-shaped blades. A temperature sensor is provided at one end of the mixing rod. A partition is arranged inside the mixing drum and below the mixing rod, and a temperature sensor is provided on the lower surface of the partition. A discharge port is arranged on the side wall of the mixing drum near the partition, and a feed port is arranged on the side wall of the mixing drum far from the partition.

[0019] The beneficial effects of the present invention are as follows: (1) The finished product of the waterborne polyurethane capsule prepared by the method of the present invention has good temperature sensitivity. The capsule is dissolved due to the self-hydration heat release of 42.5 high-heat cement, which promotes the uniform distribution of the waterborne polyurethane in the concrete, can improve the bonding force between the aggregate and the cement mortar, effectively hinder the development of cracks in all directions in the concrete, and significantly improve the compressive, crack-resistant and durability properties of the concrete; (2) The abrasion-resistant concrete prepared by the method of the present invention has stronger impact resistance compared with ordinary concrete, and it is clear that the waterborne polyurethane can improve the abrasion resistance of the polyurethane concrete; (3) The abrasion-resistant concrete prepared by the method of the present invention has a complete wall surface and a dense structure. The waterborne polyurethane can fully wrap the aggregate, and the filling density of the internal voids is relatively high, and there are no fine cracks; (4) The finished product of the waterborne polyurethane capsule prepared by the method of the present invention has a simple preparation process, low cost, and can reach a high compressive strength in a short time; at the same time, when used to prepare the abrasion-resistant concrete, it will continuously increase the connection strength between the concretes and improve the overall compressive strength of the abrasion-resistant concrete. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the outer shell mold in the preparation method of the waterborne polyurethane capsule of the present invention; Figure 2 It is a schematic structural diagram of the partition board in the preparation method of the waterborne polyurethane capsule of the present invention; Figure 3 It is a schematic structural diagram of the finished product of the waterborne polyurethane capsule prepared by the method of the present invention; Figure 4 It is a schematic structural diagram of the mixer in the preparation method of the abrasion-resistant concrete of the present invention.

[0021] In the figure, 1. bottom plate, 2. magnetic suction hemispherical base, 3. hemispherical cover plate, 4. cylindrical cutting knife, 5. double-ear seat, 6. protrusion, 7. movable plate, 8. load-bearing column, 9. wet outer shell material, 10. cutting bottom plate, 11. cutting tool, 12. capsule outer shell, 13. closed partition, 14. injection port, 15. waterborne polyurethane, 16. motor, 17. discharge port, 18. temperature sensor, 19. feed port, 20. partition, 21. stirring rod, 22. blade, 23. stirring cylinder, 24. bolt, 25. sliding track. Detailed implementation mode

[0022] The present invention will be described in detail below with reference to the accompanying drawings and specific implementation modes.

[0023] The waterborne polyurethane capsule of the present invention is composed of the following components by weight: 60 to 100 parts of aqueous polyvinyl alcohol solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of waterborne polyurethane.

[0024] Among them, the aqueous polyvinyl alcohol solution is mixed by polyvinyl alcohol particles, water, and an auxiliary agent. The mass ratio of polyvinyl alcohol particles: water: auxiliary agent is 5 to 15: 85 to 95: 0.1 to 1.5; the auxiliary agent is glycerol; The degree of polymerization of the polyvinyl alcohol particles is 500 to 2400, and the degree of alcoholysis is 87% to 89%.

[0025] The preparation method of the waterborne polyurethane capsule of the present invention is specifically implemented according to the following steps: Step 1, weigh the following raw materials by weight: 60 to 100 parts of aqueous polyvinyl alcohol solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of waterborne polyurethane; Step 2, after mixing the weighed aqueous polyvinyl alcohol solution, starch, glycerol, and glucose evenly, apply them to the stainless steel conveyor belt, and stop applying when the thickness reaches the preset thickness to obtain the wet outer shell material; Step 3, take the wet outer shell material off the stainless steel conveyor belt and put it into the outer shell mold and the partition mold respectively to prepare the hemispherical capsule outer shell and the closed partition; As Figure 1As shown in the figure, the outer shell mold includes a bottom plate 1, on which a magnetic suction hemispherical base 2 is provided. The bottom plate 1 is made of metal material. The magnetic suction hemispherical base 2 can be adsorbed on the bottom plate 1, which is convenient for disassembly, replacement and position adjustment. A hemispherical cover plate 3 is sleeved on the outer wall of the magnetic suction hemispherical base 2. The hemispherical cover plate 3 is concentric with the magnetic suction hemispherical base 2. A cylindrical cutting knife 4 is inserted at the midpoint of the hemispherical cover plate 3. The cutting edge of the cylindrical cutting knife 4 extends into the interior of the hemispherical cover plate 3 and the extending length is the same as the thickness of the wet outer shell material, which is used to cut the injection port on the wet outer shell material. A protrusion 6 is provided on the outer wall of the hemispherical cover plate 3 and close to the bottom plate 1. The protrusion 6 is connected to the upper surface of the bottom plate 1 through a double-ear seat 5; The diameter of the magnetic suction hemispherical base 2 is 20 mm; As Figure 2 As shown in the figure, the partition mold includes a cutting bottom plate 10 and a movable plate 7. Load-bearing columns 8 are provided at the four corners of the cutting bottom plate 10. Sliding tracks 25 are provided on the opposite side walls of two load-bearing columns 8 located on the same side, and sliding tracks 25 are also provided on the opposite side walls of the other two load-bearing columns 8 located on the same side. A slider is provided in each sliding track 25. The four sliders are respectively arranged on the two side walls of the movable plate 7. Through the cooperation of the sliders and the sliding tracks 25, the movable plate 7 can slide up and down relative to the load-bearing columns 8. A number of cutting tools 11 arranged in a matrix are provided on the lower surface of the movable plate 7. The cutting tools 11 are cylindrical with an inner diameter of 25 mm. The cut closed partition is circular. A through hole A is provided at one end of each load-bearing column 8 and the sliding track 25 away from the cutting bottom plate 10. Each slider is provided with a through hole B. A pin 24 is inserted into each through hole A and its corresponding through hole B. After cutting, the movable plate 7 is moved up to align the through hole A with the through hole B, and then the pin 24 is inserted into the through hole A and the through hole B to fix the position of the movable plate 7. When in use, the pin 24 is taken out and the movable plate 7 can be moved down for cutting.

[0026] The specific process is as follows: Open the hemispherical cover plate 3, take the wet outer shell material off the stainless steel conveyor belt and place it on the magnetic suction hemispherical base 2 to ensure that the wet outer shell material completely covers the magnetic suction hemispherical base 2. After closing the hemispherical cover plate 3, press the hemispherical cover plate 3, and the wet outer shell material is cut out with an injection port by the cylindrical cutting knife 4. After drying, it is peeled off to obtain a hemispherical capsule shell with a wall thickness of 5 mm; Take the wet outer shell material off the stainless steel conveyor belt and place it on the cutting bottom plate 10. Take out the pin 24, and the movable plate 7 moves down along the sliding track 25. Cut the wet outer shell material with the cutting tools 11. After cutting, move the movable plate 7 up along the sliding track 25 to align the through hole A with the through hole B, and then insert the pin 24 into the through hole A and the through hole B to fix the movable plate 7. After the cut wet outer shell material dries, take it out to obtain a closed partition; Step 4: Take two hemispherical capsule shells and a closed partition board. Paste the acrylic adhesives at the open ends of the two capsule shells on both sides of the closed partition board respectively, and obtain a spherical polyvinyl alcohol capsule shell after heat treatment. Among them, the temperature of the heat treatment is 60°C to 80°C, and the time is 10 min to 30 min. Step 5: Inject aqueous polyurethane into the spherical polyvinyl alcohol capsule shell through the injection port. After the injection is completed, apply hot melt adhesive or inject PVA solution to seal the injection port, and obtain the finished aqueous polyurethane capsule as Figure 3 shown. The finished aqueous polyurethane capsule is spherical, and its structure is as follows: it includes a closed partition board 13, hemispherical capsule shells 12 are bonded on both sides of the closed partition board 13, an injection port 14 is arranged at the center of each hemispherical capsule shell 12, and aqueous polyurethane 15 is filled in each hemispherical capsule shell 12.

[0027] For the spherical polyvinyl alcohol capsule shell of the present invention, through the esterification cross-linking reaction between starch and polyvinyl alcohol, the hydroxyl groups between molecules are reduced, the hydrogen bond action is weakened, the crystallinity is reduced, and at the same time, a small molecule plasticizer glycerol is added to reduce the melting point.

[0028] The abrasion-resistant and erosion-resistant concrete of the present invention is composed of 42.5°C high-heat cement, aggregate, water, finished aqueous polyurethane capsules and admixtures. The mass ratio of 42.5 high-heat cement, aggregate, water, finished aqueous polyurethane capsules and admixtures is 383.84 - 400:1818.18:171.72:19.19 - 20:1. The finished aqueous polyurethane capsule is prepared by the above-mentioned preparation method of aqueous polyurethane capsules. Among them, the aggregate is composed of sand and crushed stone, and the mass ratio of sand to crushed stone is 1:1.5. The admixture is composed of a water reducer, an air-entraining agent and a setting retarder, and the mass ratio of the water reducer, the air-entraining agent and the setting retarder is 19:1:4.75.

[0029] The preparation method of the abrasion-resistant and erosion-resistant concrete of the present invention is specifically implemented according to the following steps: Step 1: Weigh the raw materials according to the mass ratio: the mass ratio of 42.5 high-heat cement, aggregate, water, finished aqueous polyurethane capsules and admixtures is 383.84 - 400:1818.18:171.72:19.19 - 20:1. The finished aqueous polyurethane capsule is prepared by the above-mentioned preparation method of aqueous polyurethane capsules. Step 2: Add 42.5 high-heat cement, aggregates, water, and admixtures into a mixer and stir thoroughly to obtain a mixture. After the temperature of the mixture reaches 30°C to 35°C, add the finished product of waterborne polyurethane capsules and continue stirring until the capsule shells of the waterborne polyurethane capsules are completely hydrated and dissolved to obtain abrasion-resistant concrete; Among them, the stirring process after adding the finished product of waterborne polyurethane capsules is as follows: First, stir at a low speed for 1 minute, then adjust the frequency of the motor 16 and stir at a high speed for 2 minutes; Among them, as Figure 4 shown, the mixer includes a mixing drum 23. A motor 16 is provided at the top of the mixing drum 23. The output shaft of the motor 16 is connected to one end of a stirring rod 21. The other end of the stirring rod 21 extends into the interior of the mixing drum 23. The other end of the stirring rod 21 is connected to the open ends of a plurality of U-shaped blades 22. A partition 20 is provided in the mixing drum 23 and below the stirring rod 21. A temperature sensor 18 is provided on the lower surface of the partition 20. A discharge port 17 is provided on the side wall of the mixing drum 23 and near the partition 20. A feed port 19 is provided on the side wall of the mixing drum 23 and far from the partition 20. A valve is provided on the discharge port 17; The specific process of adding and stirring in the mixer is as follows: Add the heated cement, aggregates, water, and admixtures into the mixing drum 23, start the motor 16, and the stirring rod 21 drives the blades 22 to rotate for stirring.

[0030] The use of U-shaped blades 22 can support low-speed or progressive stirring and can reduce the shear force during stirring.

[0031] After the abrasion-resistant concrete of the present invention is poured, it needs to be vibrated immediately to avoid the initial setting of the concrete; The vibration process is as follows: The abrasion-resistant concrete is poured in layers, and the thickness of each layer of pouring is 15 cm to 20 cm. After each layer of pouring is completed, it needs to be vibrated with an inserted vibrator. The vibrator is vertically inserted into the abrasion-resistant concrete of each layer of pouring until it reaches the abrasion-resistant concrete of the lower layer that has been poured. At the same time, when inserting the vibrator, it needs to move from the edge to the center. During vibration, the spacing between the insertion points of the vibrator is controlled at 30 cm to 50 cm, and the vibration time for each point is 10 s to 20 s, based on the surface showing slurry and no bubbles emerging, to avoid over-vibration or missed vibration, and the vibration frequency is 30 Hz to 50 Hz.

[0032] During vibration, avoid staying at the same position for a long time. You can slightly move the vibrator after each insertion to ensure uniform vibration, and air bubbles and voids are fully excluded. Slowly pull out the vibrator during vibration to avoid generating cavities.

[0033] The curing process of using the abrasion-resistant concrete of the present invention is as follows: The anti-abrasion concrete is cured after its initial setting (2 h - 4 h after pouring). Steam curing is adopted, with the curing temperature being 40°C - 60°C to avoid the decomposition of polyurethane or the decline of its performance caused by high temperature. The heating rate should not be greater than 10°C / h to avoid cracking caused by sudden temperature changes. The relative humidity should be maintained at 90% - 100% to ensure the full hydration of cement. The curing time is 12 h - 24 h. After the curing ends, the cooling rate should not be greater than 10°C / h to avoid excessive temperature difference.

[0034] Example 1 The preparation method of the waterborne polyurethane capsule of the present invention is specifically implemented according to the following steps: Step 1: Weigh the following raw materials by weight: 60 parts of aqueous polyvinyl alcohol solution, 400 parts of starch, 5 parts of glycerol, 10 parts of glucose, and 1200 parts of waterborne polyurethane; The aqueous polyvinyl alcohol solution is composed of polyvinyl alcohol particles with a polymerization degree of 500 - 2400 and a degree of alcoholysis of 88%, water, and glycerol. The mass ratio of polyvinyl alcohol particles: water: glycerol is 5:85:0.1; Step 2: After uniformly mixing the weighed aqueous polyvinyl alcohol solution, starch, glycerol, and glucose, apply them on the stainless - steel conveyor belt. Stop applying when the thickness reaches 5 mm to obtain the wet outer - shell material; Step 3: Open the hemispherical cover 3, take the wet outer - shell material off the stainless - steel conveyor belt and place it on the magnetic - absorption hemispherical base 2 to ensure that the wet outer - shell material completely covers the magnetic - absorption hemispherical base 2. After closing the hemispherical cover 3, press the hemispherical cover 3, and the wet outer - shell material is cut out an injection port by the cylindrical cutting knife 4. After drying, peel it off to obtain the hemispherical capsule shell; Take the wet outer - shell material off the stainless - steel conveyor belt and place it on the cutting bottom plate 10. Take the hook off the U - shaped connecting piece, press the movable plate 7 down along the load - bearing column 8, cut the wet outer - shell material with the cutting tool 11. After cutting, move the movable plate 7 up along the load - bearing column 8, hang the hook on the U - shaped connecting piece, and take out the cut wet outer - shell material after drying to obtain the closed partition. The diameter of the closed partition is 25 mm; Step 4: Take two hemispherical capsule shells and a closed partition, and paste the acrylic adhesives at the open ends of the two capsule shells on both sides of the closed partition respectively. After heat treatment, obtain the spherical polyvinyl alcohol capsule shell; Among them, the temperature of the heat treatment is 60°C and the time is 30 min; Step 5: Inject waterborne polyurethane into the spherical polyvinyl alcohol capsule shell through the injection port. The filling amount of waterborne polyurethane is 95% of the volume of the polyvinyl alcohol capsule shell. After the injection ends, apply hot - melt adhesive or inject PVA solution to seal the injection port. After curing for 30 min, obtain the finished waterborne polyurethane capsule.

[0035] The preparation method of the anti - abrasion concrete of the present invention is specifically implemented according to the following steps: Step 1: Weigh the raw materials according to the mass ratio. The mass ratio of cement, aggregate, water, finished product of waterborne polyurethane capsules and admixture is 383.84:1818.18:171.72:19.19:1; Step 2: Add 42.5 high-heat cement, aggregate, water and admixture into a mixer and stir thoroughly to obtain a mixture. After the temperature of the mixture reaches 30 °C, add the finished product of waterborne polyurethane capsules and continue to stir until the capsule shell of the waterborne polyurethane capsules is completely hydrated and dissolved to obtain abrasion-resistant concrete; Among them, the stirring process after adding the finished product of waterborne polyurethane capsules is as follows: first stir at a low speed for 1 min, then adjust the frequency of the motor 16 and stir at a high speed for 2 min.

[0036] Example 2 The difference between the preparation method of the waterborne polyurethane capsules of the present invention and that of Example 1 lies in: Weigh the following raw materials by weight: 80 parts of aqueous polyvinyl alcohol solution, 450 parts of starch, 6.5 parts of glycerol, 15 parts of glucose, and 1300 parts of waterborne polyurethane.

[0037] The preparation method of the abrasion-resistant concrete of the present invention is the same as that of Example 1.

[0038] Example 3 The difference between the preparation method of the waterborne polyurethane capsules of the present invention and that of Example 1 lies in: Weigh the following raw materials by weight: 100 parts of aqueous polyvinyl alcohol solution, 500 parts of starch, 8 parts of glycerol, 20 parts of glucose, and 1400 parts of waterborne polyurethane; The aqueous polyvinyl alcohol solution is composed of polyvinyl alcohol particles with a polymerization degree of 500 - 2400 and a degree of alcoholysis of 89%, water, and glycerol. The mass ratio of polyvinyl alcohol particles: water: glycerol is 5:85:0.1. The preparation method of the abrasion-resistant concrete of the present invention is the same as that of Example 1.

[0039] Example 4 The preparation method of the waterborne polyurethane capsules of the present invention is specifically implemented according to the following steps: Step 1: Weigh the following raw materials by weight: 80 parts of aqueous polyvinyl alcohol solution, 400 parts of starch, 6 parts of glycerol, 15 parts of glucose, and 1300 parts of waterborne polyurethane; The aqueous polyvinyl alcohol solution is composed of polyvinyl alcohol particles with a polymerization degree of 500 - 2400 and a degree of alcoholysis of 87%, water, and glycerol. The mass ratio of polyvinyl alcohol particles: water: glycerol is 15:95:1.5; Step 2: After mixing the weighed aqueous polyvinyl alcohol solution, starch, glycerol, and glucose evenly, apply them on a stainless-steel conveyor belt and stop applying when the thickness reaches 5 mm to obtain a wet shell material; Step 3: open the hemispherical cover plate 3, remove the wet shell material from the stainless steel transmission belt and place it on the magnetic hemispherical base 2, ensuring that the wet shell material completely covers the magnetic hemispherical base 2. After closing the hemispherical cover plate 3, press the hemispherical cover plate 3, and the wet shell material is cut into an injection port by the cylindrical cutting knife 4. After drying, peel it off to form a hemispherical capsule shell. Remove the wet shell material from the stainless steel conveyor belt and place it on the cutting base 10. Remove the hook from the U-shaped connector, press the movable plate 7 down along the load-bearing column 8, and use the cutting tool 11 to cut the wet shell material. After cutting, move the movable plate 7 up along the load-bearing column 8 and hang the hook on the U-shaped connector. After the cut wet shell material is dried, take it out to obtain a closed partition with a diameter of 25 mm. Step 4: Take two hemispherical capsule shells and a closed partition, adhere the open ends of the two capsule shells to both sides of the closed partition with acrylic adhesive, and obtain spherical polyvinyl alcohol capsule shells after heat treatment; The heat treatment temperature is 70°C and the time is 20 min. Step 5: inject water-based polyurethane into the shell of the spherical polyvinyl alcohol capsule through the injection port. The filling amount of water-based polyurethane is 100% of the volume of the polyvinyl alcohol capsule shell. After the injection, apply hot melt adhesive or inject PVA solution to the injection port for sealing. After curing for 30 minutes, the finished water-based polyurethane capsule is obtained.

[0040] The method for preparing the impact-resistant concrete of the present invention is specifically implemented according to the following steps: Step 1, weighing raw materials according to the mass ratio: 42.5 high-heat cement, aggregate, water, water-based polyurethane capsule finished product and admixture are 383.84:1818.18:171.72:19.46:1; Step 2: Add 42.5 high-heat cement, aggregate, water, and admixtures into a mixer and stir thoroughly to obtain a mixture. When the mixture temperature reaches 35° C., add the finished waterborne polyurethane capsule and continue stirring until the capsule shell of the finished waterborne polyurethane capsule is completely hydrated and dissolved, thereby obtaining abrasion-resistant concrete. The stirring process after adding the finished waterborne polyurethane capsule is as follows: first stirring at a low speed for 1 minute, then adjusting the frequency of the motor 16 and stirring at a high speed for 2 minutes.

[0041] Example 5 The preparation method of the waterborne polyurethane capsule of the present invention is specifically implemented according to the following steps: Step 1: weigh the following raw materials by weight: 100 parts of polyvinyl alcohol aqueous solution, 450 parts of starch, 5 parts of glycerol, 20 parts of glucose, and 1400 parts of water-based polyurethane; The polyvinyl alcohol aqueous solution is prepared by mixing polyvinyl alcohol particles with a degree of polymerization of 500-2400 and a degree of alcoholysis of 88%, water, and glycerol. The mass ratio of polyvinyl alcohol particles: water: glycerol is 10:90:1. Step 2: Evenly mix the weighed polyvinyl alcohol aqueous solution, starch, glycerol, and glucose, and apply the mixture on a stainless steel conveyor belt. Stop applying the mixture when the thickness reaches 5 mm to obtain a wet shell material. Step 3: open the hemispherical cover plate 3, remove the wet shell material from the stainless steel transmission belt and place it on the magnetic hemispherical base 2, ensuring that the wet shell material completely covers the magnetic hemispherical base 2. After closing the hemispherical cover plate 3, press the hemispherical cover plate 3, and the wet shell material is cut into an injection port by the cylindrical cutting knife 4. After drying, peel it off to form a hemispherical capsule shell. Remove the wet shell material from the stainless steel conveyor belt and place it on the cutting base 10. Remove the hook from the U-shaped connector, press the movable plate 7 down along the load-bearing column 8, and use the cutting tool 11 to cut the wet shell material. After cutting, move the movable plate 7 up along the load-bearing column 8 and hang the hook on the U-shaped connector. After the cut wet shell material is dried, take it out to obtain a closed partition with a diameter of 25 mm. Step 4: Take two hemispherical capsule shells and a closed partition, adhere the open ends of the two capsule shells to both sides of the closed partition with acrylic adhesive, and obtain spherical polyvinyl alcohol capsule shells after heat treatment; The heat treatment temperature is 80°C and the time is 10 min. Step 5: inject water-based polyurethane into the shell of the spherical polyvinyl alcohol capsule through the injection port. The filling amount of water-based polyurethane is 100% of the volume of the polyvinyl alcohol capsule shell. After the injection, apply hot melt adhesive or inject PVA solution to the injection port for sealing. After curing for 30 minutes, the finished water-based polyurethane capsule is obtained.

[0042] The method for preparing the impact-resistant concrete of the present invention is specifically implemented according to the following steps: Step 1, weighing raw materials according to the mass ratio: 42.5 high-heat cement, aggregate, water, water-based polyurethane capsule finished product and admixture are 383.84:1818.18:171.72:19.73:1; Step 2: Add 42.5 high-heat cement, aggregate, water, and admixtures into a mixer and stir thoroughly to obtain a mixture. When the mixture temperature reaches 35° C., add the finished waterborne polyurethane capsule and continue stirring until the capsule shell of the finished waterborne polyurethane capsule is completely hydrated and dissolved, thereby obtaining abrasion-resistant concrete. The stirring process after adding the finished waterborne polyurethane capsule is as follows: first stirring at a low speed for 1 minute, then adjusting the frequency of the motor 16 and stirring at a high speed for 2 minutes.

[0043] Example 6 The preparation method of the aqueous polyurethane capsule of the present invention is specifically implemented according to the following steps: Step 1, weigh the following raw materials by weight: 100 parts of aqueous polyvinyl alcohol solution, 500 parts of starch, 8 parts of glycerol, 20 parts of glucose, and 1400 parts of aqueous polyurethane; The aqueous polyvinyl alcohol solution is composed of polyvinyl alcohol particles with a polymerization degree of 500 - 2400 and a degree of alcoholysis of 89%, water, and glycerol. The mass ratio of polyvinyl alcohol particles: water: glycerol is 15:95:1.5; Step 2, after mixing the weighed aqueous polyvinyl alcohol solution, starch, glycerol, and glucose evenly, apply them on the stainless - steel conveyor belt. Stop applying when the thickness reaches 5 mm to obtain a wet outer shell material; Step 3, open the hemispherical cover plate 3, remove the wet outer shell material from the stainless - steel conveyor belt and place it on the magnetic - absorption hemispherical base 2 to ensure that the wet outer shell material completely covers the magnetic - absorption hemispherical base 2. After closing the hemispherical cover plate 3, press the hemispherical cover plate 3. The wet outer shell material is cut out an injection port by the cylindrical cutting knife 4, and after drying, it is peeled off to obtain a hemispherical capsule shell; Remove the wet outer shell material from the stainless - steel conveyor belt and place it on the cutting bottom plate 10. Remove the hook from the U - shaped connecting piece, press down the movable plate 7 along the load - bearing column 8, cut the wet outer shell material with the cutting tool 11. After cutting, move the movable plate 7 up along the load - bearing column 8, hang the hook on the U - shaped connecting piece, and take out the cut wet outer shell material after drying to obtain a closed partition. The diameter of the closed partition is 25 mm; Step 4, take two hemispherical capsule shells and a closed partition, paste the acrylic adhesives at the open ends of the two capsule shells on both sides of the closed partition respectively, and obtain a spherical polyvinyl alcohol capsule shell after heat treatment; Among them, the temperature of the heat treatment is 60 °C and the time is 20 min; Step 5, inject aqueous polyurethane into the spherical polyvinyl alcohol capsule shell through the injection port. The filling amount of the aqueous polyurethane is 100% of the volume of the polyvinyl alcohol capsule shell. After the injection is completed, apply hot - melt adhesive or inject PVA solution to seal the injection port, and obtain the finished product of the aqueous polyurethane capsule after curing for 30 min.

[0044] The preparation method of the impact - resistant and abrasion - resistant concrete of the present invention is specifically implemented according to the following steps: Step 1, weigh the raw materials according to the mass ratio: the mass ratio of 42.5 high - heat cement, aggregate, water, the finished product of the aqueous polyurethane capsule, and the admixture is 400:1818.18:171.72:20:1; Step 2: Add 42.5 high-heat cement, aggregates, water, and admixtures into a mixer and stir thoroughly to obtain a mixture. After the temperature of the mixture reaches 30°C, add the finished product of waterborne polyurethane capsules and continue stirring until the capsule shell of the waterborne polyurethane capsules is completely hydrated and dissolved to obtain abrasion-resistant concrete. Among them, the stirring process after adding the finished product of waterborne polyurethane capsules is as follows: First, stir at a low speed for 1 minute, then adjust the frequency of the motor 16 and stir at a high speed for 2 minutes.

[0045] Comparative example The difference between the concrete preparation method and that of Example 1 is that the finished product of waterborne polyurethane capsules is not added, and the rest is exactly the same as that of Example 1.

[0046] Respectively make the abrasion-resistant concrete obtained in Example 1, Example 2, and Example 3 and the concrete obtained in the comparative example into specimens. The conditions and methods of the preparation time are exactly the same. The specimens are used to measure the compressive strength and abrasion resistance. The specific test data are shown in Table 1.

[0047] Table 1

[0048] It can be seen from Table 1 that the compressive strength and abrasion resistance of the abrasion-resistant concrete prepared by the method of the present invention far exceed those of the comparative example. Therefore, the compressive strength and abrasion resistance of the abrasion-resistant concrete prepared by the method of the present invention are both relatively high.

Claims

1. A waterborne polyurethane capsule, characterized in that It consists of the following components by weight parts: 60 to 100 parts of polyvinyl alcohol aqueous solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of waterborne polyurethane.

2. The aqueous polyurethane capsule according to claim 1, wherein The polyvinyl alcohol aqueous solution is made by mixing polyvinyl alcohol particles, water, and an auxiliary agent. The mass ratio of polyvinyl alcohol particles: water: auxiliary agent is 5 - 15: 85 - 95: 0.1 - 1.

5. The degree of polymerization of the polyvinyl alcohol particles is 500 - 2400, and the degree of alcoholysis is 87% - 89%.

3. Preparation method of aqueous polyurethane capsules, characterized in that, Specifically, it is implemented according to the following steps: Step 1, weigh the following raw materials by weight parts: 60 to 100 parts of polyvinyl alcohol aqueous solution, 400 to 500 parts of starch, 5 to 8 parts of glycerol, 10 to 20 parts of glucose, and 1200 to 1400 parts of waterborne polyurethane. Step 2, after uniformly mixing the weighed polyvinyl alcohol aqueous solution, starch, glycerol, and glucose, apply it to a stainless - steel conveyor belt. Stop applying when the thickness reaches the preset thickness to obtain a wet outer shell material. Step 3, remove the wet outer shell material from the stainless - steel conveyor belt and put it into an outer shell mold and a partition mold respectively to prepare a capsule outer shell and a closed partition. Step 4, paste the open ends of the two capsule outer shells on both sides of the closed partition respectively, and obtain a spherical polyvinyl alcohol capsule outer shell after heat treatment. Step 5, inject waterborne polyurethane into the spherical polyvinyl alcohol capsule outer shell through an injection port. After injection, seal the injection port to obtain a finished waterborne polyurethane capsule.

4. The preparation method of the aqueous polyurethane capsule according to claim 3, characterized in that, The polyvinyl alcohol aqueous solution is made by mixing polyvinyl alcohol particles, water, and an auxiliary agent. The mass ratio of polyvinyl alcohol particles: water: auxiliary agent is 5 - 15: 85 - 95: 0.1 - 1.

5. The degree of polymerization of the polyvinyl alcohol particles is 500 - 2400, and the degree of alcoholysis is 87% - 89%.

5. The preparation method of the aqueous polyurethane capsule according to claim 3, wherein, The outer shell mold includes a bottom plate (1). A magnetic - adsorption hemispherical base (2) is arranged on the bottom plate (1). A hemispherical cover plate (3) is covered on the outer wall of the magnetic - adsorption hemispherical base (2). The hemispherical cover plate (3) is concentric with the magnetic - adsorption hemispherical base (2). A cylindrical cutting knife (4) is inserted at the mid - point of the hemispherical cover plate (3). A protrusion (6) is arranged on the outer wall of the hemispherical cover plate (3) and near the bottom plate (1). The protrusion (6) is connected to the upper surface of the bottom plate (1) through a double - ear seat (5). The partition mold includes a cutting base plate (10) and a movable plate (7), and the four corners of the cutting base plate (10) are provided with load-bearing columns (8), wherein two load-bearing columns (8) located on the same side are provided with sliding rails (25) on the opposite side walls, and the other two load-bearing columns (8) located on the same side are provided with sliding rails (25) on the opposite side walls, and each of the sliding rails (25) is provided with a slider, and the four sliders are respectively provided on the two side walls of the movable plate (7), and a plurality of cutting tools (11) arranged in a matrix are provided on the lower surface of the movable plate (7), and each of the load-bearing columns (8) and the sliding rail (25) is provided with a through hole A at one end away from the cutting base plate (10), and each of the sliders is provided with a through hole B, and each through hole A and its corresponding through hole B are inserted with a pin (24).

6. The preparation method of the aqueous polyurethane capsule according to claim 3, characterized in that, In step 4, the heat treatment temperature is 60° C. to 80° C., and the time is 10 min to 30 min.

7. Impact-resistant and wear-resistant concrete, characterized in that, The method comprises 42.5 high-heat cement, aggregate, water, a finished water-based polyurethane capsule product and an admixture, wherein the mass ratio of the 42.5 high-heat cement, aggregate, water, the finished water-based polyurethane capsule product and the admixture is 383.84-400:1818.18:171.72:19.19-20:1; The finished waterborne polyurethane capsule is prepared by the preparation method according to any one of claims 3 to 7.

8. The abrasion-resistant concrete according to claim 7, wherein The aggregate is composed of sand and gravel, and the mass ratio of the sand to the gravel is 1:1.5; The admixture consists of a water reducer, an air entraining agent, and a retarder, and the mass ratio of the water reducer, the air entraining agent, and the retarder is 19:1:4.

75.

9. A method for preparing abrasion-resistant concrete, characterized in that, Please follow the steps below to implement it: Step 1, weighing raw materials according to the mass ratio: 42.5 high-heat cement, aggregate, water, water-based polyurethane capsule product and admixture are 383.84~400:1818.18:171.72:19.19~20:1; The finished waterborne polyurethane capsule is prepared by the preparation method according to any one of claims 3 to 7; Step 2: Add sand and 42.5 high-heat cement, aggregate, water and other additives during stirring, stir thoroughly to obtain a mixture, add the finished water-based polyurethane capsule when the mixture temperature reaches 30°C to 35°C, and continue stirring until the capsule shell of the finished water-based polyurethane capsule is completely hydrated and dissolved to obtain impact-resistant concrete.

10. The preparation method of the abrasion-resistant concrete according to claim 9, characterized in that, The mixer includes a mixing drum (23), a motor (16) is provided at the top of the mixing drum (23), the output shaft of the motor (16) is connected to one end of a stirring rod (21), the other end of the stirring rod (21) extends into the interior of the mixing drum (23), the other end of the stirring rod (21) is connected to the open ends of a plurality of U-shaped blades (22), a partition plate (20) is provided in the mixing drum (23) and below the stirring rod (21), a temperature sensor (18) is provided on the lower surface of the partition plate (20), a discharge port (17) is provided on the side wall of the mixing drum (23) and near the partition plate (20), and a feed port (19) is provided on the side wall of the mixing drum (23) and away from the partition plate (20).

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