Polyurethane grouting material and its application

Abstract

This invention provides a polyurethane grouting material and its application. The material comprises an active component and a curing agent component. This material continuously dissolves small molecule alcohols using a volatile organic solvent, increasing the collision probability between isocyanate monomers and small molecule alcohols, while simultaneously promoting the growth of oligomer molecular chains, effectively improving the reactivity between small molecule alcohols and isocyanate components. This material can solve the problem of low compressive strength in polyurethane grouting materials, making them unsuitable for repairing deep cavities in high-load-bearing roads.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane materials, specifically relating to a polyurethane grouting material and its application. Background Technology

[0002] Asphalt pavement is one of the most widely used road materials due to its advantages such as good driving comfort and high smoothness. Because pavement must withstand repeated loads from passing vehicles, asphalt pavement materials must possess sufficient high-temperature stability and low-temperature crack resistance, as well as durable wear resistance and skid resistance. However, in practical applications, asphalt pavement materials are frequently affected by long-term environmental factors, coupled with the characteristics of asphalt materials being prone to cracking at low temperatures and softening at high temperatures, often resulting in defects such as potholes, transverse and longitudinal cracks, and ruts.

[0003] Currently, industry experts have developed asphalt pavement repair technologies that can repair damaged pavement sections in various scenarios, extending the service life of asphalt pavements. For pothole repair, grouting materials are generally used for sealing and reinforcement. Types of grouting materials include water glass, acrylamide, methacrylic acid, polyurethane, modified epoxy resin, and lignin. Polyurethane grouting has received close attention from the industry due to its high strength, non-toxicity, and water-safety properties. Polyurethane grouting materials are broadly classified into water-soluble and oil-soluble types, both belonging to foamed polyurethane materials. They utilize the generation of bubbles to push low-viscosity grout into tiny gaps, achieving water sealing and pressure resistance. However, for applications with high load-bearing requirements, their compressive and yield strengths are insufficient.

[0004] CN118085227A reports a moisture-curing single-component polyurethane grouting material, which improves compressive strength by adjusting the isocyanate and polyether polyol components, with a maximum compressive strength of 35 MPa. CN117757025A reports a two-component polyurethane grouting material prepared from modified hyperbranched polyester. The hyperbranched network structure reduces water sensitivity, but as a reinforcing material, its maximum compressive strength is only 22 MPa. The strength standard for grouting in highway maintenance projects is a compressive strength ≥35 MPa, and for special pavements and sites, it may even be ≥40 MPa. Therefore, the higher the yield strength of the grouting material, the more beneficial it is for applications in special scenarios.

[0005] CN117946362A reports a modified two-component polyurethane grouting material, which improves the bonding strength and toughness of component A by modifying it with carboxymethyl cellulose / silica, achieving a compressive strength as high as 68 MPa. However, it requires the additional preparation of a modifier, and the low solubility of carboxymethyl cellulose in glycerol increases the number of production steps.

[0006] CN117466583A reports a high-strength grouting material for mining. By using ultrafine cement, silica fume hyperbranched polyurethane, and additives, the mechanical properties of the grouting reinforcement material are improved. Ultrafine cement provides the main strength, and modified polyurethane improves the adhesion of the grouting material. Although the compressive strength of the material is as high as 90MPa, the main load-bearing component is the cement component, and the silica fume modified polyurethane needs to be prepared separately, which is a complicated process. The grout has a high viscosity and does not have good fluidity.

[0007] In summary, current polyurethane chemical grouting materials suffer from several drawbacks: the curing agent preparation process is cumbersome; foamed grouting materials provide waterproofing and leak sealing but have low load-bearing capacity and low yield strength; and non-foamed grouting materials are prone to expansion when exposed to water, making it difficult to seal small cracks and exhibiting low compressive strength. The low compressive strength prevents them from being used for repairing deep cavities in high-load-bearing roads, a problem that urgently needs to be addressed. Summary of the Invention

[0008] One of the objectives of this invention is to provide a high-yield polyurethane grouting reinforcement material, which can solve the problem of low compressive strength of polyurethane grouting materials, making them difficult to apply to the repair of deep cavities in high-load-bearing roads.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] A polyurethane grouting road reinforcement material, the reinforcement material comprising an active component and a curing agent component;

[0011] The active component comprises the following components in parts by weight:

[0012] 70-90 parts of polyether polyol,

[0013] Compound catalyst A: 0.01-5 parts

[0014] Diluent A: 5-15 parts

[0015] 5-15 parts of reinforcing agent;

[0016] The curing agent component comprises the following components in parts by weight:

[0017] 5-15 parts of small molecule alcohol

[0018] 55-90 parts of isocyanate

[0019] Catalyst B 0-0.5 parts

[0020] Diluent B: 5-10 parts;

[0021] The mass ratio of the active component to the curing agent component is 100:(50-150), preferably 100:(90-110).

[0022] The inventors discovered that by designing the ratio of small-molecule polyols to isocyanates in the curing agent component and utilizing a dissolution-reaction-purification process, a prepolymer with low initial viscosity can be obtained. This synthesis method continuously dissolves the small-molecule alcohol in a volatile organic solvent, increasing the collision probability between the isocyanate monomer and the small-molecule alcohol. Simultaneously, it helps the oligomers grow their molecular chains, effectively improving the degree of reaction between the small-molecule alcohol and the isocyanate component. The resulting polyurethane prepolymer has a backbone containing highly sterically hindered / rigid units from the small-molecule alcohol, which intertwine with each other, enhancing the interaction between polymer chains.

[0023] In one embodiment of the present invention, the polyether polyol in the active component has a functionality of 2-3, a molecular weight of 300-5000, and a hydroxyl value of 20-600 mgKOH / g, preferably one or more of A303, A305, A307, A310, C2020, C2040, C2010, F3128, F3135, and F3156.

[0024] In one embodiment of the present invention, the composite catalyst A in the active component is obtained by combining an amine catalyst and / or a metal catalyst; preferably, the amine catalyst is a tertiary amine catalyst, preferably one or more of triethylenediamine, bis(dimethylaminoethyl) ether, bis(dimethylaminoethyl) ethylene glycol ether, dimethylcyclohexylamine, and N-methyldicyclohexylamine; preferably, the metal catalyst is one or more of a compound containing tin, potassium, zinc, and bismuth, preferably one or more of dibutyltin dilaurate, stannous octoate, di(dodecyl sulfide)dibutyltin, dibutyltin diacetate, potassium isooctanoate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth naphthenate, and bismuth laurate.

[0025] In one embodiment of the present invention, the reinforcing agent in the active component is an inorganic dehydrating agent and / or a silane coupling agent, preferably one or more of molecular sieves, calcium oxide, carbodiimide, epoxy silane, and aminopropyltrimethoxysilane.

[0026] In one embodiment of the present invention, the diluent A in the active component comprises one or more of ketones, esters, aromatic hydrocarbons, and vegetable oils, preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate.

[0027] In one embodiment of the present invention, the small molecule alcohol of the curing agent component is selected from C4-C10 sterically hindered aliphatic diols and / or C4-C10 heterocyclic diols, preferably one or more of 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 2,5-dihydroxy-1,4-dithiaane, 1,8-octanediol, and pinacol, more preferably pinacol and / or 1,8-octanediol.

[0028] In one embodiment of the present invention, the isocyanate of the curing agent component is an aromatic isocyanate, preferably toluene diisocyanate, 4,4'-diphenyl diisocyanate, diphenylmethane-4,4'-diisocyanate, polyphenyl polymethylene diisocyanate, and polymeric MDI or one or more of these.

[0029] In one embodiment of the present invention, the catalyst B of the curing agent component is a metal catalyst, preferably containing one or more of the compounds of tin, potassium, zinc, and bismuth, more preferably one or more of dibutyltin dilaurate, stannous octoate, di(dodecyl sulfide)dibutyltin, dibutyltin diacetate, potassium isooctanoate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth naphthenate, and bismuth laurate.

[0030] In one embodiment of the present invention, the diluent B of the curing agent component comprises ketones, esters, aromatic hydrocarbons, and vegetable oils, preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate, preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate.

[0031] In one embodiment of the present invention, the content of NCO groups in the curing agent component is 15.0-25.0 wt%.

[0032] Another object of the present invention is to provide an application of polyurethane grouting road reinforcement material.

[0033] One application of the above-mentioned polyurethane grouting road reinforcement material is that the material is used for deep repair of asphalt road defects, waterproofing and leak sealing, preferably for repair of void defects in high load-bearing roads, enhancing compressive strength and waterproofing and leak sealing.

[0034] Another object of the present invention is to provide a method for using polyurethane grouting road reinforcement material.

[0035] A method of using the above-mentioned polyurethane grouting road reinforcement material, wherein the method of use is as follows:

[0036] The active component and the curing agent component are mixed in a certain proportion to form a slurry. The uniformly mixed slurry is injected into the road defects through a pre-embedded pipe, especially into the deep defects of the road, and cured to obtain a high yield reinforcement material.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The polyurethane grouting reinforcement material of the present invention is based on the mixed reaction of active components and curing agent components, combined with compound catalyst. It has low viscosity in the early stage, easy and fast penetration, fast forming speed and timely solidification. It can achieve the effects of waterproofing and leak sealing and high pressure bearing for deep defects of asphalt pavement.

[0039] (2) The polyurethane grouting reinforcement material of the present invention has excellent compressive strength after being fully cured for 4 hours through the prepolymerization reaction of small molecule alcohol A and isocyanate B in the curing agent component. The yield strength of the solidified body is as high as 62MPa, which is suitable for scenarios with high load-bearing requirements. Detailed Implementation

[0040] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0041] Yield strength test method: Refer to GB / T 2567-2021.

[0042] Adhesion strength test method: Refer to the pull-off adhesion test GB / T 5210 2006.

[0043] Curing time test method: Refer to the finger touch method in GB / T 1728-2020.

[0044] NCO testing standard: Dibutylamine method, referring to GB12009.4-89

[0045] Polyether polyol A310: Glycerol-based, molecular weight 1000, functionality 3, hydroxyl value 168 mg KOH / g

[0046] Polyether polyol A305: Glycerol-based, molecular weight 500, functionality 3, hydroxyl value 336 mg KOH / g

[0047] Polyether polyol C2020: Starting with propylene glycol, molecular weight 2000, functionality 2, hydroxyl value 56 mgKOH / g

[0048] Polyether polyol F3156: Glycerol-based, molecular weight 3000, functionality 3, hydroxyl value 56 mgKOH / g

[0049] Polyether polyol A303: Glycerol-based, molecular weight 300, functionality 3, hydroxyl value 561 mgKOH / g

[0050] Bismuth laurate purity 95wt%

[0051] Dimorpholino diethyl ether (DMDEE) purity 95 wt%.

[0052] propylene carbonate purity 95wt%

[0053] Potassium isooctanoate, purity 95wt%.

[0054] Bismuth isooctanoate purity 95wt%

[0055] Dibutyltin dilaurate, purity 95wt%

[0056] Calcium oxide purity 98wt%

[0057] Molecular sieve KC313, viscosity 10000-20000 mPa·s, Wanhua Chemical Group Co., Ltd.

[0058] Pinanel, purity 99wt%, Beijing Inokai Technology Co., Ltd.

[0059] Polymer MDI: PM200, Wanhua Chemical Group Co., Ltd.

[0060] MDI-50, MDI-100: Wanhua Chemical Group Co., Ltd.

[0061] Preparation Example 1

[0062] The active ingredients, by mass, include the following components:

[0063] A310 15g

[0064] A305 18g

[0065] C2020 10g

[0066] F3156 46.9g

[0067] Compound catalyst A: 0.1g bismuth laurate, 0.05g DMDEE

[0068] 4.95g of propylene carbonate

[0069] Molecular sieve KC313 5g

[0070] The preparation method of the active component includes: according to the formula amount, adding polyols A310, A305, C2020, F3156, compound catalyst, and propylene carbonate into a stirred tank, stirring continuously for 20 minutes until uniformly mixed, adding molecular sieves into the reaction vessel, and stirring at 50°C for 30 minutes to obtain active component C1.

[0071] Preparation Example 2

[0072] The active ingredients, by mass, include the following components:

[0073] C2020 16g

[0074] A303 15g

[0075] A305 13.8g

[0076] F3156 45g

[0077] Compound catalyst A: 0.2g bismuth isooctanoate, 0.05g dibutyltin dilaurate

[0078] 4.95g of propylene carbonate

[0079] Calcium oxide 5g

[0080] The preparation method of the active component includes: according to the formula amount, polyol C2020, A303, A305, F3156, compound catalyst and diluent are continuously stirred for 20 minutes until uniformly mixed, calcium oxide is added to the reaction vessel, and stirred at 50℃ for 10-20 minutes to obtain active component C2.

[0081] Preparation Example 3

[0082] Curing agent component D1, by weight, comprises:

[0083] Pinarol 11g

[0084] Catalyst B: Potassium isooctanoate 0.5g

[0085] PM200 69.5g

[0086] MDI100 5g

[0087] MDI50 10g

[0088] 4g of propylene carbonate

[0089] The preparation method of the curing agent component includes: according to the formula amount, add pinacol to a 250ml three-necked flask, connect a dropping funnel and a vertical condenser, prepare a diluent of petroleum ether / chloroform = 1:3.5, add the prepared diluent to the dropping funnel, control the flow rate of the dropping funnel to 5ml / min, add propylene carbonate and potassium isooctanoate to the flask according to the formula amount, gradually raise the temperature to 60℃ and start stirring, preheat the formula amount of PM200, MDI50 and MDI100 to 60℃ and mix evenly, add them to the flask at an addition rate of 10g / min, after all the isocyanate components have been added, gradually raise the temperature to 80℃ and continue the reaction for 1h.

[0090] After the reaction was completed and cooled to room temperature, butyl acetate was slowly added to dilute the solution. The solution in the flask was collected, and the collected component was then rotary evaporated at a temperature controlled below 40°C to remove volatiles, yielding a curing agent component containing propylene carbonate and catalyst II. The NCO content was measured to be 20.9%, and curing agent component D1 was obtained.

[0091] Preparation Example 4

[0092] The curing agent components and their specific formulations are shown in Table 1; the unit of measurement for each component in Table 1 is "grams", and "--" indicates that the component was not added.

[0093]

[0094] In the comparative examples, the difference between curing agent components D5 and D6 and curing agent component D1 lies in the amount of pinacol used. In the comparative examples, the difference between curing agent components D7 and D8 and curing agent component D1 lies in the selection of acyclic / unhindered diols of non-small molecule alcohol A.

[0095] Example 1

[0096] A high-yield polyurethane grouting reinforcement material includes an active component C1 and a curing agent component D1, with a mass ratio of 1:0.9.

[0097] A molded body using the aforementioned polyurethane grouting reinforcement material is prepared by the following method:

[0098] Place 100g of active component C1 in a 1L container, add 90g of curing agent component D1 and start timing. Stir quickly for 20s with a stirring rod. After stirring, observe the mixture. Once it is completely cured, the molded body of high-yield polyurethane grouting material is obtained.

[0099] Example 2

[0100] A high-yield polyurethane grouting reinforcement material includes an active component C1 and a curing agent component D2, with a mass ratio of 1:0.9.

[0101] A molded body using the aforementioned polyurethane grouting reinforcement material is prepared by the following method:

[0102] Place 100g of active component C1 in a 1L container, add 90g of curing agent component D2 and start timing. Stir quickly for 20s with a stirring rod. After stirring, observe the mixture. Once it is completely cured, the molded body of high-yield polyurethane grouting material is obtained.

[0103] Examples 3-4, Comparative Examples 5-8

[0104] The preparation method of the polyurethane grouting reinforcement material is the same as that in Example 1.

[0105]

[0106] Compared to Example 1, Comparative Examples 5, 6, 7, and 8 differ in that the selected curing agent components are D5, D6, D7, and D8, respectively. The curing agent components in Comparative Examples 5-8, at their respective mass contents, resulted in polyurethane grouting materials with the same R-value.

[0107] Curing time, yield strength, and bond strength of Examples 1-6 were tested according to current usage specifications. The test results are as follows:

[0108]

[0109]

[0110] According to the test data in the table, the polyurethane grouting reinforcement material provided by this invention contains active components and curing agent components. The curing agent component is prepared through the prepolymerization reaction of small molecule alcohols and isocyanate B, and a diluent. The temperature response range of the grouting material is adjusted using a compound catalyst in the active component, giving the polyurethane grout excellent fluidity in the early stage, allowing it to quickly penetrate to the damaged area and fill small cracks. It then cures rapidly in the later stage, forming a solid body for waterproofing, leak sealing, and high-pressure load bearing. This polyurethane grouting reinforcement material features fast curing speed, simple preparation method, convenient on-site construction, excellent mechanical properties, and high yield strength. In the examples, after the active component and the curing agent component were mixed and molded, the curing time was within 120 seconds, and the yield strength was above 60 MPa. In contrast, Comparative Examples 5-8 showed a significant decrease in compressive strength. When the proportion of small molecule alcohol A in the curing agent component was too low, the yield strength of the grouting material was about 20 MPa. When small molecule alcohol A was not used, the yield strength of the grouting material synthesized only by conventional polyether polyester polyols was about 45-50 MPa. When the proportion of small molecule alcohol A was too high, due to the large steric hindrance of its molecular structure, the reaction rate and degree of polymerization between the active component and the curing agent component were both low. With the same additives, the curing time of the material was significantly prolonged and the yield strength was low. When catalyst II was not used in the curing agent component, the highly hindered hydroxyl component could not fully participate in the reaction, resulting in a high NCO content in the prepolymer. The structural advantages of the material led to a lower yield strength.

[0111] The applicant declares that this invention illustrates the polyurethane grouting reinforcement material and its application through the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials of this invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A polyurethane grouting road reinforcement material, characterized in that, The reinforcing material comprises an active component and a curing agent component; The active component comprises the following components in parts by weight: 70-90 parts of polyether polyol, Compound catalyst A: 0.01-5 parts Diluent A: 5-15 parts 5-15 parts of reinforcing agent; The curing agent component comprises the following components in parts by weight: 5-15 parts of small molecule alcohol 55-90 parts of isocyanate Catalyst B 0-0.5 parts Diluent B: 5-10 parts; The mass ratio of the active component to the curing agent component is 100:(50-150), preferably 100:(90-110).

2. The reinforcing material according to claim 1, characterized in that... The polyether polyol in the active component has a functionality of 2-3, a molecular weight of 300-5000, and a hydroxyl value of 20-600 mgKOH / g, preferably one or more of A303, A305, A307, A310, C2020, C2040, C2010, F3128, F3135, and F3156; And / or, the composite catalyst A in the active component is obtained by combining an amine catalyst and / or a metal catalyst; Preferably, the amine catalyst is a tertiary amine catalyst, and more preferably one or more of the following: triethylenediamine, bis(dimethylaminoethyl) ether, bis(dimethylaminoethyl) ethylene glycol ether, dimethylcyclohexylamine, and N-methyldicyclohexylamine; Preferably, the metal catalyst is a catalyst containing one or more of the following compounds: tin, potassium, zinc, and bismuth, and more preferably one or more of the following: dibutyltin dilaurate, stannous octanoate, di(dodecyl sulfide)dibutyltin, dibutyltin diacetate, potassium isooctanoate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth naphthenate, and bismuth laurate. And / or, the reinforcing agent in the active component is an inorganic dehydrating agent and / or a silane coupling agent, preferably one or more of molecular sieves, calcium oxide, carbodiimide, epoxy silane, and aminopropyltrimethoxysilane; And / or, the diluent A in the active component comprises one or more of ketones, esters, aromatic hydrocarbons, and vegetable oils, preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate.

3. The reinforcing material according to claim 1, characterized in that, The small molecule alcohol in the curing agent component is selected from C4-C10 sterically hindered aliphatic diols and / or C4-C10 alicyclic diols, preferably one or more of 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 2,5-dihydroxy-1,4-dithiane, 1,8-octanediol, and pinacol, more preferably pinacol and / or 1,8-octanediol; And / or, the isocyanate of the curing agent component is an aromatic isocyanate, preferably toluene diisocyanate, 4,4'-diphenyl diisocyanate, diphenylmethane-4,4'-diisocyanate, polyphenyl polymethylene diisocyanate, polymeric MDI or one or more of these. And / or, the catalyst B of the curing agent component is a metal catalyst, preferably containing one or more of the compounds of tin, potassium, zinc, and bismuth, more preferably one or more of dibutyltin dilaurate, stannous octanoate, di(dodecyl sulfide)dibutyltin, dibutyltin diacetate, potassium isooctanoate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth naphthenate, and bismuth laurate; And / or, the diluent B of the curing agent component comprises ketones, esters, aromatic hydrocarbons, vegetable oils, preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate; preferably one or more of vegetable oils, butyl acetate, ethyl acetate, xylene, propylene glycol methyl ether acetate, petroleum ether, chloroform, dimethyl carbonate, and propylene carbonate. And / or, the content of NCO groups in the curing agent component is 15.0-25.0 wt%.

4. The use of a polyurethane grouting road reinforcement material according to any one of claims 1-3, wherein the material is used for deep repair of asphalt road defects, waterproofing and leak sealing, preferably for repair of void defects in high load-bearing roads, enhancing compressive strength and waterproofing and leak sealing.

5. A method of using the polyurethane grouting road reinforcement material according to any one of claims 1-3, characterized in that, The method of use is as follows: The active component and the curing agent component are mixed in a certain proportion to form a slurry. The uniformly mixed slurry is injected into the road defect area through a pre-embedded pipe and cured to obtain a high yield reinforcement material.

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