Polyurethane grouting material and preparation method thereof

Abstract

The invention relates to the technical field of sealants, and discloses a polyurethane grouting material and a preparation method thereof.The polyurethane grouting material comprises a component A and a component B. The polyurethane grouting material is characterized in that the component A takes long-chain fatty acid modified polyether polyol as a matrix; and the component B takes a bio-based epoxy resin modified polyurethane prepolymer compound as a matrix. The preparation method of the polyurethane grouting material comprises the following steps: step 1, taking the long-chain fatty acid modified polyether polyol, the flexibilizer, the foaming agent, the adhesion promoter, the antioxidant and the catalyst, and continuously stirring to obtain the long-chain fatty acid modified polyether polyol, step 2, taking the bio-based epoxy resin, dehydrating, dropwise adding the isocyanate tripolymer under the protection of nitrogen, and stirring to obtain the polyurethane grouting material. The bio-based epoxy resin modified polyurethane prepolymer is obtained; and step 3, uniformly mixing the component A and the component B according to a certain ratio, adding a flexibilizer and a diluent, and stirring at normal temperature to obtain the bio-based epoxy resin modified polyurethane prepolymer compound. And the common problems of out-of-control foaming and insufficient strength of a traditional material in a humid environment are effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sealant, in particular to a polyurethane grouting material and a preparation method thereof. BACKGROUND

[0002] Polyurethane grouting material is widely used in highway crack repair, foundation reinforcement and waterproof plugging engineering due to its excellent permeability and construction convenience. Polyurethane grouting material is mainly divided into two categories: hydrophilic type and hydrophobic type, their preparation principles and formulations are different, but the core chemical basis is the polymerization reaction of isocyanate and polyol, the main raw materials include: isocyanate, oligomer polyol, additives (catalyst, plasticizer, flame retardant, etc.), isocyanate and oligomer polyol react to form a prepolymer agent with isocyanate groups (-NCO) at the end, during construction, the prepolymer reacts with moisture (or additional catalyst, hydroxyl-containing compounds), the foaming rate of the hydrophobic type is relatively low, and the foam structure is relatively dense. It is mainly used for structural reinforcement, foundation lifting and void filling.

[0003] Chinese patent document CN103173006A discloses a preparation method of a hydrophobic polyurethane grouting material, (1) mixing polyether polyol and chain extender uniformly, dehydrating and degassing to a water content of less than 0.05%, cooling to 30-50℃, then adding isocyanate, and reacting at a temperature of 78-85℃ for 2-3 hours to obtain a polyurethane prepolymer, the reaction endpoint is determined by the -NCO wt% content of the polyurethane prepolymer being 10-20%; wherein the weight ratio of polyether polyol: chain extender: isocyanate in the raw materials of the polyurethane prepolymer is (15-30): (0.75-3): (67-84.25);

[0004] (2) After cooling the above polyurethane prepolymer to 45℃-70℃, adding 7-10% of a solvent, 0.001-0.004% of a retarder, 1-5% of a surfactant, 0.1-2% of a catalyst and 10-30% of a plasticizer, and mixing uniformly, it is ready; wherein the percentages are weight percentages of the polyurethane prepolymer;

[0005] The polyether polyol includes polyoxypropylene polyol; the chain extender includes ethylene glycol and / or butanediol, the isocyanate includes diisocyanate and / or polyisocyanate; wherein the diisocyanate is diphenylmethane-4,4'-diisocyanate, and the polyisocyanate is polymethylene polyphenyl polyisocyanate; the catalyst is a tertiary amine catalyst; the plasticizer is one or more of diethyl phthalate, dibutyl phthalate and dioctyl phthalate; and the solvent is an organic ketone solvent. The compressive strength is 15-17kPa, and it will further decrease in a humid environment.

[0006] For example, Chinese patent document CN102341421A discloses a polyurethane foam comprising a lipid-based polyol, the isocyanate-modified polyol being used in a production process for the production of a polyurethane foam (preferably flexible) by reacting at least one polyol with at least one polyfunctional isocyanate, wherein the proportion of isocyanate is from 0.01% (preferably 0.05%, most preferably 0.1%) to 70%, preferably 60%, preferably 50%, preferably 33%, most preferably 30%, of the weight of isocyanate theoretically required for the reaction with all the available hydroxyl groups of the polyol, wherein the isocyanate-modified polyol has available hydroxyl groups for reaction with further isocyanate, the at least one polyol used to produce the isocyanate-modified polyol comprising a lipid-based polyol which preferably reacts with isocyanate in the presence of a polyurethane gel catalyst.

[0007] The conventional foaming type polyurethane material has a significant shortcoming in practical application: the density of the polyurethane grouting material decreases sharply in a humid environment, which seriously weakens the mechanical strength, resulting in insufficient adhesion to the concrete cracks and reduced reinforcement effect. Not only does it affect the penetration and filling capacity in the water-containing cracks, but also it increases the cost of the material and process. The existing grouting material is difficult to balance between application effect and economic benefit, which greatly limits its application scenarios. SUMMARY

[0008] The present application provides a polyurethane grouting material to solve the technical problem of low mechanical strength of polyurethane grouting material in a humid environment, comprising component A and component B, characterized in that component A uses long-chain fatty acid modified polyether polyol as the matrix; component B uses bio-based epoxy resin modified polyurethane prepolymer complex as the matrix.

[0009] Preferably, the bio-based epoxy resin is at least one of epoxy soybean oil, epoxy castor oil, and epoxy palm oil.

[0010] Preferably, the long-chain fatty acid is at least one of lauric acid, myristic acid, and palmitic acid.

[0011] Preferably, the weight ratio of components A and B is 100:100-120.

[0012] A preparation method of a polyurethane grouting material, comprising the following steps:

[0013] Step 1, preparation of component A: weigh 60-80 parts of long-chain fatty acid modified polyether polyol, 10-20 parts of toughening agent, 3-5 parts of foaming agent, 1-3 parts of adhesion promoter, 0.5-1 part of antioxidant, and 0.5-1 part of catalyst, continuously stir at room temperature for 1 h, to obtain long-chain fatty acid modified polyether polyol, which is component A.

[0014] Step 2, preparation of component B: 50-60 parts of bio-based epoxy resin is dehydrated, and 120-140 parts of isocyanate trimer is added dropwise under the protection of nitrogen to obtain a bio-based epoxy resin modified polyurethane prepolymer; secondly, 20-30 parts of a toughening agent and 10-15 parts of a diluent are added, and stirring is carried out at room temperature for 0.5 h to obtain a bio-based epoxy resin modified polyurethane prepolymer compound, which is component B;

[0015] Step 3: uniformly mixing components A and B at room temperature at a weight ratio of 100:100~120 to obtain a low water sensitivity high strength polyurethane grouting material.

[0016] Preferably, the preparation of long-chain fatty acid modified polyether polyol: 100-120 parts of polyether polyol and 50-60 parts of long-chain fatty acid are added, and 1-3 parts of a titanate catalyst is added, and heating and stirring are carried out to obtain a long-chain fatty acid modified polyether polyol.

[0017] Preferably, the preparation of isocyanate trimer: 40-60 parts of polyisocyanate is weighed; then 0.1-0.3 parts of a catalyst is dissolved in 20-30 parts of an aprotic solvent to prepare a solution, and the solution is slowly added dropwise under a nitrogen atmosphere, continuous stirring is carried out, 0.1 parts of phosphoric acid is added, continuous stirring is carried out, and finally excessive aprotic solvent and polyisocyanate are removed by distillation.

[0018] The present application has the following beneficial effects:

[0019] The present application proposes a multiple synergistic hydrophobic modification scheme aiming at the technical defects of high water sensitivity and easy excessive foaming of existing polyurethane grouting materials when encountering water, which leads to a decrease in strength. First, the end group of polyether polyol is modified by long-chain acid to significantly enhance the hydrophobic properties of the molecular chain; then bio-based epoxy resin is introduced into the system to further strengthen the water resistance of the material body; at the same time, a special hydrophobic catalyst is compounded to ensure that a low water sensitivity environment can be maintained during the curing reaction stage. The above three ways synergistically act on the three levels of molecular design, component compounding and reaction catalysis, and together build an efficient and stable multiple hydrophobic protection system, thereby significantly reducing the sensitivity of the material to water in a fundamental way, realizing the unity of low water absorption, high stability and good mechanical properties, and effectively overcoming the common problem of foaming out of control and insufficient strength of traditional materials in a humid environment.

[0020] 2、The present application is aimed at the problem of low strength of existing foaming polyurethane grouting materials, and innovatively constructs a cross-linking structure with multiple enhancement synergies. By introducing a bio-based epoxy resin with high-rigidity molecular chains, the mechanical strength and overall cross-linking density of the material body are effectively improved; meanwhile, the trimerization reaction of isocyanate groups is utilized to form a stable isocyanurate ring network, further strengthening the cross-linking degree of the system. These two enhancement mechanisms synergize with each other to construct a stereo network with rigidity and flexibility and high-density cross-linking inside the material, thereby realizing controllable foaming while significantly guaranteeing and improving the mechanical properties of the material in a high-foaming state. DETAILED DESCRIPTION

[0021] The following will be further described in detail through specific embodiments:

[0022] The raw materials are as follows:

[0023] 1. Polyisocyanate: at least one of polyphenyl polymethylene polyisocyanate (PAPI), 4,4'-diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI);

[0024] 2. Polyether polyol: at least one of polyether polyol YD-380, polyether polyol YD-1050, and polyether polyol YD-8238;

[0025] 3. Long-chain fatty acid: at least one of lauric acid, myristic acid, and palmitic acid;

[0026] 4. Bio-based epoxy resin: at least one of epoxy soybean oil, epoxy castor oil, and epoxy palm oil;

[0027] 5. Aprotic solvent: at least one of N,N-dimethylformamide, dimethyl sulfoxide, and toluene;

[0028] 6. Adhesion promoter: at least one of oligomeric siloxane, aminosiloxane, and vinyl oligomeric siloxane;

[0029] 7. Toughening agent: at least one of dioctyl phthalate, trimethylphenyl phosphate, and dibutyl phthalate;

[0030] Example 1

[0031] A preparation method of a polyurethane grouting material, comprising the following steps:

[0032] (1) Preparation of long-chain fatty acid modified polyether polyol: 100 parts of polyether polyol and 50 parts of lauric acid are placed in a three-necked flask, 1 part of a titanate catalyst is added, heated to 108°C, and continuously stirred for 6 h to obtain long-chain fatty acid modified polyether polyol;

[0033] (2) Preparation of A component: 60 parts of long-chain fatty acid modified polyether polyol, 10 parts of toughening agent, 3 parts of foaming agent, 1 part of adhesion promoter, 0.5 parts of antioxidant, 0.5 parts of catalyst, continuously stirring at room temperature for 1 h, to obtain modified polyether polyol, which is A component;

[0034] (3) Preparation of trimer: 40 parts of polyisocyanate is weighed in a 1000 mL three-necked flask and placed in a 55°C oil bath; then 0.1 parts of catalyst is dissolved in 20 parts of aprotic solvent to prepare a solution, which is slowly added dropwise under a nitrogen atmosphere, and continuously stirred for 6 h; the conversion rate of the reaction is monitored by sampling and control analysis of the mass fraction of -NCO, when the reaction reaches the expected conversion rate, 0.1 parts of phosphoric acid is added, and continuously stirred for 0.5 h, and finally excessive aprotic solvent and polyisocyanate are removed by distillation to obtain isocyanate trimer;

[0035] (4) Preparation of B component: 50 parts of epoxy soybean oil is dehydrated at 120°C for 2 h, then cooled to 70°C, and 120 parts of isocyanate trimer is added dropwise under the protection of nitrogen, kept at 80°C and continuously stirred for 1 h to obtain a bio-based epoxy modified polyurethane prepolymer; secondly, 20 parts of toughening agent and 10 parts of diluent are added, and stirred at room temperature for 0.5 h to obtain a bio-based epoxy modified polyurethane prepolymer compound, which is B component;

[0036] (5) The A component and the B component are mixed uniformly at room temperature according to a weight ratio of 100:120 to obtain a low water sensitivity and high strength polyurethane grouting material.

[0037] Example 2

[0038] A preparation method of a polyurethane grouting material, comprising the following steps:

[0039] (1) Preparation of long-chain fatty acid modified polyether polyol: 120 parts of polyether polyol and 60 parts of myristic acid are placed in a three-necked flask, 3 parts of titanate catalyst is added, heated to 108°C, and continuously stirred for 6 h to obtain long-chain fatty acid modified polyether polyol;

[0040] (2) Preparation of A component: 80 parts of long-chain fatty acid modified polyether polyol, 20 parts of toughening agent, 5 parts of foaming agent, 3 parts of adhesion promoter, 1 part of antioxidant, 1 part of catalyst, continuously stirring at room temperature for 1 h, to obtain modified polyether polyol, which is A component;

[0041] (3) Trimer preparation: 60 parts of polyisocyanate were weighed into a 1000 mL three-necked flask and placed in a 55 °C oil bath; then 0.3 parts of catalyst was dissolved in 30 parts of aprotic solvent to prepare a solution, which was slowly added dropwise under a nitrogen atmosphere, and stirring was continued for 6 h; the conversion rate of the reaction was monitored by sampling and analyzing the change in the mass fraction of -NCO; when the reaction reached the expected conversion rate, 0.1 parts of phosphoric acid was added, and stirring was continued for 0.5 h; finally, excess aprotic solvent and polyisocyanate were removed by distillation to obtain an isocyanate trimer;

[0042] (4) Preparation of B component: 60 parts of epoxy castor oil was dehydrated at 120 °C for 2 h, then cooled to 80 °C, and 140 parts of isocyanate trimer was added dropwise under the protection of nitrogen, kept at 80 °C and stirred for 1 h to obtain a bio-based epoxy modified polyurethane prepolymer; secondly, 30 parts of a toughening agent and 15 parts of a diluent were added, and stirred at room temperature for 0.5 h to obtain a bio-based epoxy modified polyurethane prepolymer compound, which was the B component;

[0043] (5) The A component and the B component were mixed uniformly at room temperature according to a weight ratio of 100:110 to obtain a low water sensitivity and high strength polyurethane grouting material.

[0044] Comparative Example 1

[0045] A method for preparing a polyurethane grouting material, comprising the following steps:

[0046] (1) Preparation of A component: 60 parts of polyether polyol, 10 parts of toughening agent, 3 parts of foaming agent, 1 part of adhesion promoter, 0.5 parts of antioxidant, and 0.5 parts of catalyst were weighed, and stirred at room temperature for 1 h to obtain the A component;

[0047] (2) Trimer preparation: 40 parts of polyisocyanate were weighed into a 1000 mL three-necked flask and placed in a 55 °C oil bath; then 0.1 parts of catalyst was dissolved in 20 parts of aprotic solvent to prepare a solution, which was slowly added dropwise under a nitrogen atmosphere, and stirring was continued for 6 h; the conversion rate of the reaction was monitored by sampling and analyzing the change in the mass fraction of -NCO; when the reaction reached the expected conversion rate, 0.1 parts of phosphoric acid was added, and stirring was continued for 0.5 h; finally, excess aprotic solvent and polyisocyanate were removed by distillation to obtain an isocyanate trimer;

[0048] (3) Preparation of B component: 50 parts of epoxy soybean oil was dehydrated at 120 °C for 2 h, then cooled to 70 °C, and 120 parts of isocyanate trimer was added dropwise under the protection of nitrogen, kept at 80 °C and stirred for 1 h to obtain a bio-based epoxy modified polyurethane prepolymer; secondly, 20 parts of a toughening agent and 10 parts of a diluent were added, and stirred at room temperature for 0.5 h to obtain a bio-based epoxy modified polyurethane prepolymer compound, which was the B component;

[0049] (4) The A component and the B component are mixed uniformly at room temperature according to a weight ratio of 100:120, and a polyurethane grouting material is obtained.

[0050] Comparative Example 2

[0051] A preparation method of a polyurethane grouting material, comprising the following steps:

[0052] (1) Preparation of long-chain fatty acid modified polyether polyol: 100 parts of polyether polyol and 50 parts of lauric acid are placed in a three-necked flask, 1 part of a titanate catalyst is added, heated to 108°C, and continuously stirred for 6h to obtain a long-chain fatty acid modified polyether polyol preparation;

[0053] (2) Preparation of A component: 60 parts of long-chain fatty acid modified polyether polyol preparation, 10 parts of toughening agent, 3 parts of foaming agent, 1 part of adhesion promoter, 0.5 parts of antioxidant, and 0.5 parts of catalyst are weighed, and continuously stirred at room temperature for 1h to obtain a modified polyether polyol, which is the A component;

[0054] (3) Preparation of B component: 120 parts of isocyanate, 20 parts of toughening agent, and 10 parts of diluent are added, and stirred at room temperature for 0.5h to obtain the B component;

[0055] (4) The A component and the B component are mixed uniformly at room temperature according to a weight ratio of 100:120, and a polyurethane grouting material is obtained.

[0056] Comparative Example 3 (neither long-chain diacid modified polyol nor trimer epoxy is added, and a conventional grouting material is prepared for comparison)

[0057] According to Examples 1, 2 and Comparative Examples 1, 2, polyurethane grouting materials are prepared, and the foaming ratio of the polyurethane grouting material under the same room temperature water-rich environment condition, the compressive strength of the polyurethane solidified body formed, are tested according to the standard JC / T 2041-2020 “Polyurethane Grouting Material”, and the adhesion strength of the polyurethane grouting material to the wet concrete base surface is tested according to the standard GB / T 16777-2008 “Building Waterproof Coating Test Method”. The test results are shown in Table 1.

[0058] Table 1 Test results Test item

[0059]

[0060] As shown in Table 1, the modified polyurethane grouting material of the present application not only has controllable foaming ratio in water-rich environment, but also exhibits excellent mechanical properties. This is due to the multiple synergistic mechanisms of its molecular design: first, the end group modification of polyether polyol by long-chain acid, and the synergistic introduction of bio-based epoxy resin and special catalyst, significantly enhance the hydrophobicity of the molecular chain, so as to realize the controllable foaming in water-rich environment. Secondly, the introduction of high-rigidity bio-based epoxy resin and the trimerization reaction of isocyanate group, together build a high-density crosslinking network with rigidity and flexibility, which essentially guarantees the mechanical strength of the material in the high-foaming state.

[0061] The above-mentioned is only an embodiment of the present application, and the common knowledge of specific structures and properties in the scheme is not described in detail here. The person skilled in the art knows all the ordinary technical knowledge in the field of the present application before the filing date or the priority date, can know all the prior art in this field, and has the ability to apply conventional experimental means before that date. The person skilled in the art can improve and implement the present scheme based on their own ability under the guidance of this application. Some typical known structures or known methods should not be an obstacle for the person skilled in the art to implement the present application. It should be noted that for those skilled in the art, without departing from the structure of the present application, a number of modifications and improvements can be made, which should also be considered as the protection scope of the present application. These will not affect the effect and practicality of the present application. The protection scope of the present application should be subject to the content of its claims, and the specific implementation mode and the like in the specification can be used to explain the content of the claims.

Claims

1. A polyurethane grouting material comprising a component A and a component B, characterized in that, A component is long-chain fatty acid modified polyether polyol as the matrix; B component is bio-based epoxy resin modified polyurethane prepolymer complex as the matrix.

2. The polyurethane grouting material according to claim 1, characterized in that: Bio-based epoxy resin: at least one of epoxy soybean oil, epoxy castor oil, epoxy palm oil.

3. Polyurethane grouting material according to claim 2, characterized in that: Long-chain fatty acid: at least one of lauric acid, myristic acid, palmitic acid.

4. The polyurethane grouting material according to claim 3, characterized in that: The weight ratio of A and B components is 100:100~120.

5. Process for the production of polyurethane grouts according to claim 4, characterized in that: Comprising the following steps: Step 1, A component preparation: weigh 60-80 parts of long-chain fatty acid modified polyether polyol, 10-20 parts of toughening agent, 3-5 parts of foaming agent, 1-3 parts of adhesion promoter, 0.5-1 parts of antioxidant, 0.5-1 parts of catalyst, continuously stirring at room temperature for 1h, obtaining long-chain fatty acid modified polyether polyol, which is A component; Step 2, B component preparation: weigh 50-60 parts of bio-based epoxy resin dehydration, under the protection of nitrogen, drop 120-140 parts of isocyanate trimer, obtain bio-based epoxy resin modified polyurethane prepolymer; Secondly, add 20-30 parts of toughening agent, 10-15 parts of diluent, stir at room temperature for 0.5h, obtain bio-based epoxy resin modified polyurethane prepolymer complex, which is B component Step 3, mix A component and B component according to the weight ratio of 100:100~120 at room temperature, you can get low water sensitivity high strength polyurethane grouting material.

6. The process for the preparation of polyurethane grouts according to claim 5, characterized in that: Preparation of long-chain fatty acid modified polyether polyol: 100-120 parts of polyether polyol and 50-60 parts of long-chain fatty acid, then add 1-3 parts of titanate catalyst, heating and stirring, obtaining long-chain fatty acid modified polyether polyol.

7. The process for the preparation of polyurethane grouts according to claim 6, characterized in that: Preparation of isocyanate trimer: weigh 40-60 parts of polyisocyanate; Then 0.1-0.3 parts of catalyst is dissolved in 20-30 parts of aprotic solvent to prepare a solution, slowly drop the solution under nitrogen atmosphere, continuously stirring, add 0.1 parts of phosphoric acid, continuously stirring, finally remove excess aprotic solvent and polyisocyanate by distillation.

Images