Silicate modified polyurethane foaming material for coal mine spraying and preparation method of silicate modified polyurethane foaming material

Abstract

The invention discloses a silicate modified polyurethane foam material for coal mine spraying and a preparation method of the silicate modified polyurethane foam material, and belongs to the technical field of sodium silicate modified organic polymer materials. The coating is composed of a component A and a component B, the component A comprises the following raw materials in parts by weight: 25-35 parts of waterborne polyurethane and 65-75 parts of a sodium silicate aqueous solution; the component B is prepared from the following raw materials in parts by weight: 65 to 75 parts of polyisocyanate and 10 to 15 parts of polyether glycol; the foaming mechanism is that the polyurethane foam material is formed by CO2 gas generated by chemical reaction of isocyanate and water. The problem that the flash point of the material is reduced by using a foaming agent is avoided; and the product does not precipitate or layer in the storage and transportation processes.

Description

Technical Field

[0001] The present invention belongs to the technical field of sodium silicate modified organic polymer materials, and particularly relates to a sodium silicate modified polyurethane foaming material for coal mine spraying and a preparation method thereof. Background Art

[0002] With the continuous development of China's coal mining industry, some roof caving phenomena, severe truncation and penetration of water flow or rock and coal seams, emergency gas leakage plugging, emergency fire isolation, etc. often occur during coal mining. Therefore, it is necessary to take filling and repairing measures for roof caving areas, water seepage areas, gas leakage areas, etc. before coal mining can be carried out again. The currently used spraying materials are mainly polyurethane foaming resin, phenolic foaming resin and sodium silicate polyurethane foaming resin. These foaming resins all have certain defects: (1) Phenolic foaming resin has a relatively high content of free aldehyde and free phenol, and pungent gases will be released during curing. Phenolic foaming resin mainly uses organic acids and inorganic acids as curing agents, which cause serious metal corrosion. The cured product of phenolic foaming resin has a problem of flame spread after encountering fire, which is a potential safety hazard; (2) In polyurethane foaming resin, blowing agent 141b or blowing agents with low boiling point and low flash point are added. During foaming, due to severe heat release, the central temperature can exceed 230 °C, which is extremely easy to ignite the blowing agent and cause a fire. Coupled with the low oxygen index of foamed polyurethane (generally about 28), there are major safety hazards. Many coal mines in China have clearly stipulated that polyurethane foaming resin cannot be used as a filling material; (3) Sodium silicate polyurethane foaming resin is a relatively excellent spraying and foaming material. It not only has a relatively high oxygen index, generally reaching more than 35, but also has a low reaction temperature and no release of toxic and harmful gases, which is environmentally friendly and safe. However, due to the use of sodium silicate aqueous solution, the product is brittle, has no elongation rate, and even slight deformation will cause the spraying surface to break. To solve this problem, a certain amount of polyether diol is generally added to increase the toughness of the material. However, polyether diol is incompatible with sodium silicate aqueous solution and the density difference between the two is too large, resulting in rapid stratification and extremely difficult to mix evenly by shaking, which greatly changes the use effect and even causes the phenomenon of inability to foam and cure.

[0003] Chinese invention patent CN104558477 B introduces a sodium silicate modified polyurethane foaming material, its preparation method and use method. This invention adds polyether materials such as polyether diol Tdiol-400, GE-210, DL-2000, YD-2020, etc. to the sodium silicate aqueous solution to improve the comprehensive performance of the product, but the patent does not describe the stability of this component during storage.

[0004] The Chinese invention patent CN114456350 A introduces a sodium silicate modified polymer foaming material for filling and sealing. In this invention, a phosphorus-containing diol is synthesized to modify isocyanate, and polyethylene glycol 400 or polyethylene glycol 600 is added to the aqueous sodium silicate solution to obtain a sodium silicate modified polymer foaming material with good performance. However, since a thin-film evaporator is required to remove free TDI in the modified polyurethane in the patent, it causes certain difficulties in its industrial production and results in a relatively high product cost. Summary of the Invention

[0005] The present invention overcomes the deficiencies of the prior art and provides a sodium silicate modified polyurethane foaming material for coal mine spraying and its preparation method, solving the problems of easy stratification and instability of the sodium silicate modified polyurethane foaming material.

[0006] The present invention is achieved through the following technical solutions: A sodium silicate modified polyurethane foaming material for coal mine spraying consists of component A and component B; Component A includes the following raw materials in parts by weight: 25 - 35 parts of waterborne polyurethane and 65 - 75 parts of aqueous sodium silicate solution; Component B includes the following raw materials in parts by weight: 65 - 75 parts of polyisocyanate and 10 - 15 parts of polyether diol.

[0007] Preferably, component A further includes 1 - 3 parts by weight of foam stabilizer and 1 - 3 parts by weight of catalyst.

[0008] Preferably, component B further includes 15 - 20 parts by weight of halogen-free phosphorus-containing flame retardant.

[0009] Preferably, the modulus of the aqueous sodium silicate solution is 2.7 - 3.0, and the Baume degree is 48.

[0010] More preferably, the foam stabilizer is one or both of foam stabilizer SH-493 and SH-431.

[0011] More preferably, the catalyst is one or any combination of dimethylaminoethoxyethanol (DMAEE), triethylenediamine (A-33), and pentamethyldiethylenetriamine (PC-5).

[0012] Preferably, the polyether diol is polyether YD-2020 or polytetrahydrofuran diol PTMEG2000; the polyisocyanate is PM-200 or PM-400.

[0013] The preparation method of the sodium silicate modified polyurethane foaming material for coal mine spraying includes the following steps: S1. Synthesis of aqueous polyurethane: Mix 80 parts of polyether YD-204 or PTMEG-400 with 14 - 16 parts of DMPA or DMBA, then conduct dehydration treatment. Cool down to 55 - 65°C and gradually add dropwise 35 - 40 parts of TDI or MDI-50 or IPDI. React at 75 - 85°C for 1 - 2 h, then cool down to 45 - 55°C and add 5 - 7 parts of triethylamine. After emulsification, aqueous polyurethane is obtained. S2. Preparation of component A: Gradually add 25 - 35 parts of aqueous polyurethane to 65 - 75 parts of sodium silicate aqueous solution under stirring, stir evenly, and add 1 - 3 parts of catalyst under stirring. Stir evenly to obtain component A. S3. Preparation of component B: Conduct dehydration treatment on 10 - 15 parts of polyether diol, cool down to 35 - 45°C, add 65 - 75 parts of polyisocyanate, react at 70 - 80°C for 1 - 2 h, and then cool down to 25 - 35°C to obtain component B. The above parts are all parts by weight.

[0014] Preferably, when in use, mix component A and component B evenly according to a volume ratio of 1:1.

[0015] Preferably, the dehydration treatment is to dehydrate at 110°C under a vacuum of more than -0.85 MPa for 1 h.

[0016] The beneficial effects of the present invention compared with the prior art are as follows: 1. For the sodium silicate-modified polyurethane foaming material for coal mine spraying of the present invention, through the modification of silicate and polyisocyanate, during the foaming, shaping and curing process of the material, the internal temperature does not exceed 90°C at the highest.

[0017] 2. The sodium silicate-modified polyurethane foaming material for coal mine spraying of the present invention does not contain foaming agent in its raw materials. Its foaming mechanism is that the CO2 gas formed by the chemical reaction of isocyanate and water generates the polyurethane foam material. It avoids the problem of reducing the flash point of the material due to the use of foaming agent. The product does not precipitate and does not delaminate during storage and transportation.

[0018] 3. The sodium silicate-modified polyurethane foaming material for coal mine spraying of the present invention mainly uses sodium silicate aqueous solution, modified polyurethane prepolymer and chlorine-free phosphorus-containing flame retardant. Compared with phenolic foaming materials, it does not contain harmful substances such as free aldehyde and free phenol, and does not emit pungent aldehyde and phenol odors during curing; there is no problem of flame continuation after curing, and there are no acidic or alkaline substances in the cured body, and it will not cause any corrosion to metal materials.

[0019] 4. The sodium silicate modified polyurethane foaming material for coal mine spraying mainly uses an aqueous sodium silicate solution, a modified polyurethane prepolymer, and a chlorine-free phosphorus-containing flame retardant. Compared with the polyurethane foaming material, 55% of the mass fraction is an aqueous polyurethane mixed with an aqueous sodium silicate solution component, and it contains more water. Therefore, during the foaming, molding, and curing process, its heat release is lower, the internal temperature does not exceed 90 °C at the highest, and the oxygen index ≥ 35.

[0020] 5. The sodium silicate modified polyurethane foaming material for coal mine spraying of the present invention will not show problems such as stratification and sedimentation during long-term storage of its A and B components, nor will it show problems such as agglomeration and viscosity change.

[0021] 6. All raw materials of the sodium silicate modified polyurethane foaming material for coal mine spraying of the present invention are common raw materials in the market, which are simple and easy to obtain. Its synthesis and preparation method is easy to operate and convenient for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a comparison picture of Comparative Example 1; Figure 2 It is a comparison picture of Comparative Example 2; Figure 3 It is a comparison picture of Comparative Example 3; Figure 4 It is a comparison picture of Comparative Example 4; Figure 5 It is a comparison picture of Comparative Example 5; Figure 6 It is a comparison picture of Comparative Example 6; Figure 7 It is a comparison picture of Comparative Example 7; Figure 8 It is a comparison picture of Comparative Example 8; Figure 9 It is a foaming photo of Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0023] In order to make the technical problems, technical solutions, and beneficial effects to be solved by the present invention clearer and more understandable, the present invention will be further described in detail in combination with the examples and the drawings. It should be understood that the specific examples described herein are only used to explain the present invention and are not used to limit the present invention. The technical solutions of the present invention will be described in detail below in combination with the examples and the drawings, but the protection scope is not limited by this.

[0024] Example 1 This embodiment provides a sodium silicate-modified polyurethane foaming material for coal mine spraying and its preparation method; the sodium silicate-modified polyurethane foaming material for coal mine spraying mainly includes component A and component B. Among them, component A is a composition with waterborne polyurethane mixed with sodium silicate aqueous solution as the main body; component B is a prepolymer with polyisocyanate as the main body. The specific preparation method is as follows: S1. Synthesis of waterborne polyurethane Mix 80 parts of polyether YD-204 and 14 parts of DMPA together, dehydrate at 110°C and a vacuum degree above -0.85 MPa for 1 h, cool down to 60°C and gradually add 35 parts of TDI (T-80). After adding TDI, react at 80°C for 1.5 h, cool down to 50°C and add 6 parts of triethylamine (TEA), and emulsify with 150 parts of deionized water dissolved with 2 parts of NaOH to obtain waterborne polyurethane with a solid content of 45%.

[0025] S2. Mixing of component A of sodium silicate-modified polyurethane foaming material Gradually add 35 parts of waterborne polyurethane to 65 parts of sodium silicate aqueous solution under stirring, stir evenly, and add 2 parts of DMAEE under stirring, and stir evenly to obtain component A of sodium silicate-modified polyurethane foaming material.

[0026] S3. Synthesis of component B of sodium silicate-modified polyurethane foaming material Take 10 parts of polytetrahydrofuran diol PTMEG2000, dehydrate at 110°C and a vacuum degree above -0.85 MPa for 1 h, cool down to 40°C, add 75 parts of PM-200, add 15 parts of triethyl phosphate (TEP), and react at 75°C for 1.5 h and then cool down to 30°C to obtain component B of sodium silicate-modified polyurethane foaming material.

[0027] S4. Mix and foam component A and component B of sodium silicate-modified polyurethane foaming material at a volume ratio of 1:1, record the surface dry time, maximum reaction temperature, expansion ratio, and test its tensile strength, elongation at break, bond strength, air permeability, oxygen index, surface resistance, flash points of A and B materials and other properties.

[0028] Example 2 This embodiment provides a sodium silicate-modified polyurethane foaming material for coal mine spraying and its preparation method; the specific preparation method is as follows: S1. Synthesis of waterborne polyurethane 80 parts of PTMEG-400 and 16 parts of DMBA were mixed together, dehydrated at 110 °C under a vacuum of more than -0.85 MPa for 1 h, cooled to 60 °C, and 50 parts of MDI-50 were gradually added dropwise. After adding MDI-50, the reaction was carried out at 80 °C for 1.5 h, cooled to 50 °C, 6 parts of triethylamine (TEA) were added, and emulsified with 170 parts of deionized water dissolved with 2 parts of NaOH to obtain an aqueous polyurethane with a solid content of 45%.

[0029] S2. Mixing of Component A of Sodium Silicate Modified Polyurethane Foaming Material 35 parts of the aqueous polyurethane were gradually added to 65 parts of sodium silicate aqueous solution under stirring, stirred evenly, and 3 parts of A-33 were added under stirring and stirred evenly to obtain Component A of the sodium silicate modified polyurethane foaming material.

[0030] S3. Synthesis of Component B of Sodium Silicate Modified Polyurethane Foaming Material 10 parts of polytetrahydrofuran diol PTMEG2000 were dehydrated at 110 °C under a vacuum of more than -0.85 MPa for 1 h, cooled to 40 °C, 75 parts of PM-200 were added, 15 parts of triethyl phosphate (TEP) were added, and the reaction was carried out at 75 °C for 1.5 h and cooled to 30 °C to obtain Component B of the sodium silicate modified polyurethane foaming material.

[0031] S4. Mix the Component A and Component B of the sodium silicate modified polyurethane foaming material in a volume ratio of 1:1 for foaming, record the surface drying time, maximum reaction temperature, expansion ratio, and test its tensile strength, elongation at break, bonding strength, air permeability, oxygen index, surface resistance, flash points of Component A and Component B, etc.

[0032] Example 3 This example presents a sodium silicate modified polyurethane foaming material for coal mine spraying and its preparation method; the specific preparation method is as follows: S1. Synthesis of Aqueous Polyurethane 80 parts of PTMEG-400 and 16 parts of DMBA were mixed together, dehydrated at 110 °C under a vacuum of more than -0.85 MPa for 1 h, cooled to 60 °C, and 50 parts of MDI-50 were gradually added dropwise. After adding MDI-50, the reaction was carried out at 80 °C for 1.5 h, cooled to 50 °C, 6 parts of triethylamine (TEA) were added, and emulsified with 170 parts of deionized water dissolved with 2 parts of NaOH to obtain an aqueous polyurethane with a solid content of 45%.

[0033] S2. Mixing of Component A of Sodium Silicate Modified Polyurethane Foaming Material 35 parts of the aqueous polyurethane were gradually added to 65 parts of sodium silicate aqueous solution under stirring, stirred evenly, and 1 part of PC-5 was added under stirring and stirred evenly to obtain Component A of the sodium silicate modified polyurethane foaming material.

[0034] S3. Synthesis of Component B of Sodium Silicate Modified Polyurethane Foaming Material Take 10 parts of polyether YD-2020, dehydrate it at 110°C under a vacuum of more than -0.85 MPa for 1 h, cool it down to 40°C, add 75 parts of PM-400, add 15 parts of triethyl phosphate (TEP), react at 75°C for 1.5 h, and then cool it down to 30°C to obtain Component B of sodium silicate modified polyurethane foaming material.

[0035] S4. Mix and foam Component A and Component B of sodium silicate modified polyurethane foaming material at a volume ratio of 1:1, record the surface drying time, maximum reaction temperature, expansion ratio, and test its tensile strength, elongation at break, bond strength, air permeability, oxygen index, surface resistance, flash points of Component A and Component B, etc.

[0036] Example 4 This example presents a sodium silicate modified polyurethane foaming material for coal mine spraying and its preparation method; the specific preparation method is as follows: S1. Synthesis of Waterborne Polyurethane Mix 80 parts of polyether YD-204 and 14 parts of DMPA together, dehydrate it at 110°C under a vacuum of more than -0.85 MPa for 1 h, cool it down to 60°C, gradually add 35 parts of TDI (T-80) dropwise, react at 80°C for 1.5 h after adding TDI, cool it down to 50°C, add 6 parts of triethylamine (TEA), and emulsify it with 170 parts of deionized water dissolved with 2 parts of NaOH to obtain a waterborne polyurethane with a solid content of 45%.

[0037] S2. Mixing of Component A of Sodium Silicate Modified Polyurethane Foaming Material Gradually add 35 parts of waterborne polyurethane to 65 parts of sodium silicate aqueous solution under stirring, stir evenly, add 2 parts of DMAEE under stirring, and stir evenly to obtain Component A of sodium silicate modified polyurethane foaming material.

[0038] S3. Synthesis of Component B of Sodium Silicate Modified Polyurethane Foaming Material Take 10 parts of polyether YD-2020, dehydrate it at 110°C under a vacuum of more than -0.85 MPa for 1 h, cool it down to 40°C, add 75 parts of PM-400, add 15 parts of triethyl phosphate (TEP), react at 75°C for 1.5 h, and then cool it down to 30°C to obtain Component B of sodium silicate modified polyurethane foaming material.

[0039] S4. Mix and foam Component A and Component B of sodium silicate modified polyurethane foaming material at a volume ratio of 1:1, record the surface drying time, maximum reaction temperature, expansion ratio, and test its tensile strength, elongation at break, bond strength, air permeability, oxygen index, surface resistance, flash points of Component A and Component B, etc.

[0040] The sources of the above components are as follows: Polyether YD-204 produced by Hebei Yadong Chemical Group Co., Ltd.; Polytetrahydrofuran diol (PTMEG) 400 produced by Shandong Deyitai New Materials Co., Ltd.; Dimethylolpropionic acid (DMPA) produced by Zhangjiagang Yaru Chemical Co., Ltd.; Toluene diisocyanate (T-80) produced by Gansu Yinguang Chemical Industry Group; Triethylamine (TEA) produced by Guide Chemical; Polyether YD-2020 produced by Hebei Yadong Chemical Group Co., Ltd.; Polytetrahydrofuran diol PTMEG2000 produced by Shandong Deyitai New Materials Co., Ltd.; PM-200 or PM-400 produced by Yantai Wanhua Polyurethane Co., Ltd.; Flame retardant triethyl phosphate (TEP) produced by Shandong Yarong Chemical Co., Ltd.; Foam stabilizers SH-493 and SH-431 of Hubei Longsheng Sihai New Materials Co., Ltd.

[0041] The performance tests of Examples 1-4 are shown in the following table: Comparative Example 1 Mix 8 parts of polyethylene glycol 400, 1 part of cosolvent, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 1 the first from the left); mix 8 parts of polyether diol 204, 1 part of cosolvent op-10, 2 parts of catalyst (a mixture of DMAEE and PC-5 with a mass ratio of 1:1), and 89 parts of sodium silicate aqueous solution evenly ( Figure 1 the second from the left); mix 8 parts of polyether diol 220, 1 part of cosolvent, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 1 the third from the left); mix 8 parts of polyether diol 210, 1 part of cosolvent, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution ( Figure 1 the fourth from the left) evenly, and then let them all stand for 1 h; Take 22 parts of the silicate-modified polyurethane foam materials prepared in Examples 1, 2, 3, and 4 respectively and put them into four test tubes, and then add to each test tube: 1 part of foam stabilizer SH-493, 2 parts of catalyst (a mixture of DMAEE and PC-5 with a mass ratio of 1:1), and 75 parts of sodium silicate aqueous solution. After mixing evenly, let them stand for 1 h and then compare the stratification conditions in the pictures (the 4 on the right), see Figure 1 .

[0042] Comparative Example 2 Mix 8 parts of polyethylene glycol 400, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly, and then it will immediately stratify. See Figure 2 .

[0043] Comparative Example 3 After standing the 8 test tubes in Comparative Example 1 for 24 h, observe the comparative stratification. See Figure 3 .

[0044] Comparative Example 4 Mix 8 parts of polyethylene glycol 400, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 4 the first from the left); mix 8 parts of polyether diol 204, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 4 the second from the left); mix 8 parts of polyether diol 220, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 4 the third from the left); mix 8 parts of polyether diol 210, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution ( Figure 4 the fourth from the left) evenly, and then conduct a 24 - h storage experiment. See Figure 4 .

[0045] Comparative Example 5 After standing the 8 test tubes in Comparative Example 1 for 3 days, observe the comparative stratification situation. See Figure 5 .

[0046] Comparative Example 6 After standing the 8 test tubes in Comparative Example 1 for 7 days, observe the comparative stratification situation. See Figure 6 .

[0047] Comparative Example 7 After standing the 8 test tubes in Comparative Example 1 for 30 days, observe the comparative stratification situation. See Figure 7 .

[0048] Comparative Example 8 Mix 8 parts of polyethylene glycol 400, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 8 the first from the left); mix 8 parts of polyether diol 204, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 8 the second from the left); mix 8 parts of polyether diol 220, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution evenly ( Figure 8 the third from the left); mix 8 parts of polyether diol 210, 1 part of solubilizer, 2 parts of catalyst, and 89 parts of sodium silicate aqueous solution ( Figure 8The proportion of (the fourth from the left) was evenly mixed and left to stand for 3 months for the storage experiment.

[0049] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific embodiments of the present invention are limited thereto. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the present invention, several simple deductions or substitutions can still be made, and all should be regarded as falling within the scope of patent protection determined by the claims submitted for the present invention.

Claims

1. A silicate-modified polyurethane foaming material for coal mine spraying, characterized in that It consists of Component A and Component B; Component A includes the following raw materials in parts by weight: 25 - 35 parts of aqueous polyurethane and 65 - 75 parts of sodium silicate aqueous solution; Component B includes the following raw materials in parts by weight: 65 - 75 parts of polyisocyanate and 10 - 15 parts of polyether diol.

2. The silicate-modified polyurethane foaming material for coal mine spraying according to claim 1, wherein, Component A also includes 1 - 3 parts by weight of foam stabilizer and 1 - 3 parts by weight of catalyst.

3. The silicate-modified polyurethane foaming material for coal mine spraying according to claim 1, wherein, Component B also includes 15 - 20 parts by weight of halogen-free phosphorus-containing flame retardant.

4. A silicate-modified polyurethane foaming material for coal mine spraying according to claim 1, characterized in that, The modulus of the sodium silicate aqueous solution is 2.7 - 3.0, and the Baume degree is 48.

5. A silicate-modified polyurethane foaming material for coal mine spraying according to claim 2, characterized in that, The foam stabilizer is one or both of foam stabilizer SH-493 and SH-431.

6. The silicate-modified polyurethane foaming material for coal mine spraying according to claim 2, wherein, The catalyst is one or any combination of dimethylaminoethoxyethanol, triethylenediamine, and pentamethyldiethylenetriamine.

7. The silicate-modified polyurethane foaming material for coal mine spraying according to claim 1, characterized in that, The polyether diol is polyether YD-2020 or polytetrahydrofuran diol PTMEG2000; the polyisocyanate is PM-200 or PM-400.

8. The preparation method of a silicate-modified polyurethane foaming material for coal mine spraying according to any one of claims 1-7, characterized in that, It includes the following steps: S1. Synthesis of aqueous polyurethane: Mix 80 parts of polyether YD-204 or PTMEG-400 with 14 - 16 parts of DMPA or DMBA, then perform dehydration treatment, cool down to 55 - 65 °C, gradually dropwise add 35 - 40 parts of TDI or MDI-50 or IPDI, react at 75 - 85 °C for 1 - 2 h, then cool down to 45 - 55 °C and add 5 - 7 parts of triethylamine, and obtain aqueous polyurethane after emulsification. S2. Preparation of Component A: Gradually add 25 - 35 parts of aqueous polyurethane to 65 - 75 parts of sodium silicate aqueous solution under stirring, stir evenly, add 1 - 3 parts of catalyst under stirring, and stir evenly to obtain Component A. S3. Preparation of Component B: Dehydrate 10 - 15 parts of polyether diol, cool down to 35 - 45 °C, add 65 - 75 parts of polyisocyanate, react at 70 - 80 °C for 1 - 2 h, and cool down to 25 - 35 °C to obtain Component B. The above parts are all in parts by weight.

9. The preparation method of a silicate-modified polyurethane foaming material for coal mine spraying according to claim 8, characterized in that, When in use, mix Component A and Component B evenly according to a volume ratio of 1:

1.

10. The preparation method of a silicate-modified polyurethane foaming material for coal mine spraying according to claim 8, characterized in that, The dehydration treatment is to dehydrate at 110 °C and a vacuum degree above -0.85 MPa for 1 h.

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