Phenolic resin foam material for filling and sealing of coal mine, preparation method and application

Abstract

The invention relates to a phenolic resin foam material for filling and sealing a coal mine as well as a preparation method and application thereof, belongs to the technical field of phenolic resin materials, and solves the technical problems that the performance of the existing phenolic resin foam material cannot meet the construction requirements of underground operation of the coal mine and the national safety production industry standard and the like. Comprising a component A and a component B in a volume ratio of 4: (0.85-1.15), and the component A comprises cationic waterborne polyurethane, phenolic resin, carbonate and a foam stabilizer; and the component B comprises phenolsulfonic acid, phosphoric acid and water. The preparation method comprises the following steps: step a, preparing cationic waterborne polyurethane; b, preparing the component A; c, preparing a component B; and step d, preparing the phenolic resin foaming material. Compared with the prior art, the invention has the advantages of meeting the construction requirements of coal mine underground operation and the national safety production industry standard, being convenient for large-scale production, improving the mechanical property and safety, and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of phenolic resin materials, specifically relating to a phenolic resin foaming material for coal mine filling and sealing, its preparation method, and its application. Background Technology

[0002] Phenolic resin foam is a closed-cell rigid foam plastic made primarily of phenolic resin with added additives. It possesses excellent thermal insulation, waterproofing, moisture resistance, flame retardancy, non-flame propagation, and low thermal conductivity, while also exhibiting certain mechanical strength, air tightness, and durability. Due to its superior performance, phenolic resin foam plays a vital role in various industries. Particularly in coal mine filling and sealing applications, it demonstrates unique advantages, providing strong protection for safe coal mine production. However, with increasingly stringent requirements in underground coal mines and increasingly stringent national safety standards, the maximum reaction temperature, toughness, dust shedding performance, and mechanical properties of existing phenolic resin foam materials cannot meet the construction requirements and national safety standards for certain special underground coal mine operations. Summary of the Invention

[0003] In order to overcome the shortcomings of existing technologies and solve the technical problems that the performance of existing phenolic resin foam materials cannot meet the construction requirements of underground coal mine operations and national safety production industry standards, this invention provides a phenolic resin foam material for coal mine filling and sealing, its preparation method, and its application.

[0004] The present invention is achieved through the following technical solutions.

[0005] This invention provides a phenolic resin foaming material for coal mine filling and sealing, comprising component A and component B in a volume ratio of 4:(0.85-1.15). Component A comprises cationic aqueous polyurethane, phenolic resin, carbonate, and a foaming agent. The cationic aqueous polyurethane is composed of a diol, methyl diethanolamine, toluene diisocyanate or diphenyl toluene diisocyanate, hydrochloric acid, an emulsifier, and deionized water. The diol is one or more of polyether, polytetrahydrofuran diol, and aromatic polyester polyol. The emulsifier is one or more of Tween-80 and OP-10. Component B comprises phenol sulfonic acid, phosphoric acid, and water.

[0006] Furthermore, by mass, component A comprises: 15-30 parts cationic waterborne polyurethane, 59-76 parts phenolic resin, 8 parts carbonate and 3 parts foam stabilizer.

[0007] Furthermore, by mass parts, component B comprises: 65 parts phenolsulfonic acid, 15 parts phosphoric acid, and 20 parts water.

[0008] Furthermore, the phenolic resin is a first-order phenolic resin, the solid content of the phenolic resin is 72±2%, the viscosity of the phenolic resin is 260±20 mPa·s, the pH of the phenolic resin is 7±0.3, the free formaldehyde content in the phenolic resin is ≤0.4%, and the free phenol content in the phenolic resin is ≤8%.

[0009] Furthermore, the carbonate is magnesium carbonate.

[0010] Furthermore, the foaming agent is Tween-80.

[0011] Furthermore, a method for preparing a phenolic resin foam material for coal mine filling and sealing includes the following steps: Step a: Preparation of cationic waterborne polyurethane: 400 parts of polyether or polytetrahydrofuran glycol or aromatic polyester polyol and 12 parts of methyldiethanolamine were mixed and placed at 110°C and a vacuum of -0.85 MPa or higher for 1 hour to dehydrate. After cooling to 40°C, 70-100 parts of toluene diisocyanate or diphenyltoluene diisocyanate were added dropwise and reacted at 75°C for 1.5 hours. Phenol, the end-capping agent, was added and the temperature was increased to 85°C by increasing the temperature at 5°C for 0.5 hours. Then, the temperature was decreased to 65°C by decreasing the temperature at 5°C for 0.5 hours. Finally, 3.7 parts of hydrochloric acid, 20 parts of emulsifier OP-10 and 526-556 parts of deionized water were added to emulsify and obtain cationic waterborne polyurethane. Step b, Preparation of component A: Component A is obtained by uniformly mixing 15-30 parts of cationic waterborne polyurethane, 59-76 parts of phenolic resin, 8 parts of carbonate and 3 parts of foam stabilizer obtained in step a. Step c, Preparation of component B: Component B is obtained by mixing 65 parts of phenolsulfonic acid, 15 parts of phosphoric acid and 20 parts of water evenly. Step d: Preparation of phenolic resin foam material: Component A and component B are mixed evenly at a volume ratio of 4:(0.85-1.15) to obtain phenolic resin foam material.

[0012] Furthermore, the application of the phenolic resin foaming material for coal mine filling and sealing in coal mine filling, construction of firewalls, and sealing walls.

[0013] The beneficial effects achieved by this invention are: 1. The cationic waterborne polyurethane modified phenolic resin foaming material prepared by the present invention uses cationic waterborne polyurethane to modify phenolic resin, thereby reducing the hydroxymethyl content in the phenolic foaming material so that its internal temperature does not exceed 75°C during curing. 2. The raw materials of this invention do not contain volatile, flammable, explosive, or low-boiling-point foaming agents. The foaming mechanism of this invention is that acid reacts with carbonate to generate CO2 for foaming, which avoids the problem of lowering the flash point of the material by using solvent foaming agents and improves the safety of use. 3. Compared with ordinary phenolic resin foaming materials, the cationic waterborne polyurethane modified phenolic resin foaming material prepared in this invention increases the toughness of phenolic resin through cationic waterborne polyurethane chains. The urethane bonds, ether bonds, and ester bonds form a large number of hydrogen bonds with the hydrogen on the phenolic resin, which can effectively solve the powdering phenomenon caused by the brittleness of phenolic resin. It has a certain deformation capacity. Under certain pressure, the foaming material will not break or break after the coal seam is displaced or deformed, and there will be no gas leakage through the cracks. It meets the construction requirements of underground coal mine operations and national safety production industry standards, and avoids secondary filling and sealing. 4. The cationic waterborne polyurethane modified phenolic resin foam material prepared by the present invention has long and flexible cationic waterborne polyurethane chains. Phenol is used as a capping agent. Phenol can undergo a grafting reaction with phenolic resin to uniformly distribute polyurethane chains in phenolic resin. This not only improves the comprehensive mechanical properties of the foam, but also reduces the content of hydroxymethyl groups in phenolic resin, thereby lowering the reaction temperature during curing. 5. All raw materials used in this invention are common in the market, easy to obtain, and their synthesis and preparation methods are easy to operate and facilitate large-scale production.

[0014] Compared with existing technologies, the present invention has the advantages of meeting the construction requirements of underground coal mine operations and national safety production industry standards, facilitating large-scale production, and improving mechanical properties and safety. Attached Figure Description

[0015] Figure 1 This is a product diagram of the cationic waterborne polyurethane in this invention; Figure 2 This is a product image of the cationic waterborne polyurethane modified phenolic resin foaming material of this invention; Figure 3 This is a product image of unmodified traditional phenolic resin foaming material. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0017] like Figures 1 to 3 As shown. Example 1

[0018] A phenolic resin foaming material for coal mine filling and sealing includes component A and component B in a volume ratio of 4:1. Component A includes cationic aqueous polyurethane, phenolic resin, carbonate, and a foaming agent; component B includes phenol sulfonic acid, phosphoric acid, and water. By mass, component A comprises 20 parts cationic aqueous polyurethane, 69 parts phenolic resin, 8 parts carbonate, and 3 parts foaming agent; by mass, component B comprises 65 parts phenol sulfonic acid, 15 parts phosphoric acid, and 20 parts water. The cationic aqueous polyurethane is composed of polyether (YD-220) produced by Hebei Yadong Chemical Group Co., Ltd., methyl diethanolamine (MDEA) produced by Zhangjiagang Yarui Chemical Co., Ltd., diphenyltoluene diisocyanate (MDI-50) produced by Wanhua Chemical Group Co., Ltd., hydrochloric acid (HCl aqueous solution, concentration 36.5%) produced by Gaide Chemical, emulsifier OP-10 from Jiangsu Haian Petrochemical Plant, and deionized water. The phenolic resin is a first-order phenolic resin with a solid content of 71%, a viscosity of 260 mPa·s, a pH of 7.1, a free formaldehyde content of 0.31%, and a free phenol content of 3.86%. The carbonate is magnesium carbonate. The foaming agent is Tween-80.

[0019] A method for preparing a phenolic resin foam material for sealing coal mine filling includes the following steps: Step a: Preparation of cationic waterborne polyurethane: 400 parts of polyether (YD-220) and 12 parts of methyl diethanolamine (MDEA) were mixed and dehydrated at 110°C and a vacuum of -0.85 MPa or higher for 1 hour. After cooling to 40°C, 70 parts of diphenyltoluene diisocyanate (MDI-50) were added dropwise and reacted at 75°C for 1.5 hours. Then, 21 parts of phenol, the end-capping agent, were added, and the temperature was increased to 85°C by increasing the temperature every 5°C for 0.5 hours. After cooling to 65°C by decreasing the temperature every 5°C for 0.5 hours, 3.7 parts of hydrochloric acid, 20 parts of emulsifier OP-10, and 526 parts of deionized water were added to emulsify and obtain a cationic waterborne polyurethane with a solid content of 50%. Cationic waterborne polyurethane has long and highly flexible chains. Phenol is used as a capping agent. Phenol can undergo a grafting reaction with phenolic resin, which distributes the polyurethane chains evenly in the phenolic resin. This not only improves the overall mechanical properties of the foam, but also reduces the hydroxymethyl content in the phenolic resin, thus lowering the reaction temperature during curing. Step b, Preparation of component A: The 20 parts of cationic waterborne polyurethane, 69 parts of phenolic resin, 8 parts of carbonate and 3 parts of foam stabilizer obtained in step a are mixed evenly to obtain component A. Cationic waterborne polyurethane modifies phenolic resin, increasing the toughness of the phenolic resin by forming a large number of hydrogen bonds. This effectively solves the problem of powder shedding caused by the brittleness of phenolic resin. It has a certain deformation capacity, and the foamed material does not crack or break after coal seam displacement or deformation under certain pressure. It will not cause gas to escape through cracks, meeting the construction requirements of underground coal mine operations and national safety production industry standards, and avoiding secondary filling and sealing. Step c, Preparation of component B: Component B is obtained by mixing 65 parts of phenolsulfonic acid, 15 parts of phosphoric acid and 20 parts of water evenly. Step d: Preparation of phenolic resin foam material: Component A and component B are mixed evenly at a volume ratio of 4:1 to obtain phenolic resin foam material. Example 2

[0020] A phenolic resin foaming material for coal mine filling and sealing includes component A and component B in a volume ratio of 4:1. Component A includes cationic aqueous polyurethane, phenolic resin, carbonate, and a foaming agent; component B includes phenol sulfonic acid, phosphoric acid, and water. By mass, component A comprises 20 parts cationic aqueous polyurethane, 69 parts phenolic resin, 8 parts carbonate, and 3 parts foaming agent; by mass, component B comprises 65 parts phenol sulfonic acid, 15 parts phosphoric acid, and 20 parts water. The cationic aqueous polyurethane is composed of polytetrahydrofuran diol (PTMEG2000) produced by Shandong Deyitai New Material Co., Ltd., methyl diethanolamine (MDEA) and diphenyltoluene diisocyanate (MDI-50) produced by Zhangjiagang Yarui Chemical Co., Ltd., hydrochloric acid (HCl aqueous solution, concentration 36.5%) produced by Gaide Chemical, emulsifier OP-10 from Jiangsu Haian Petrochemical Plant, and deionized water. The phenolic resin is a first-order phenolic resin with a solid content of 72%, a viscosity of 265 mPa·s, a pH of 7.2, a free formaldehyde content of 0.32%, and a free phenol content of 3.91%. The carbonate is magnesium carbonate. The foaming agent is Tween-80.

[0021] A method for preparing a phenolic resin foam material for sealing coal mine filling includes the following steps: Step a: Preparation of cationic waterborne polyurethane: 400 parts of polytetrahydrofuran glycol (PTMEG2000) and 12 parts of methyldiethanolamine (MDEA) were mixed and dehydrated at 110°C and a vacuum of -0.85 MPa or higher for 1 hour. After cooling to 40°C, 70 parts of diphenyltoluene diisocyanate (MDI-50) were added dropwise and reacted at 75°C for 1.5 hours. Then, 21 parts of phenol, the end-capping agent, were added, and the temperature was increased to 85°C by increasing the temperature every 5°C for 0.5 hours. After cooling to 65°C by decreasing the temperature every 5°C for 0.5 hours, 3.7 parts of hydrochloric acid, 20 parts of emulsifier OP-10, and 526 parts of deionized water were added to emulsify and obtain a cationic waterborne polyurethane with a solid content of 50%. Cationic waterborne polyurethane has long and highly flexible chains. Phenol is used as a capping agent. Phenol can undergo a grafting reaction with phenolic resin, which distributes the polyurethane chains evenly in the phenolic resin. This not only improves the overall mechanical properties of the foam, but also reduces the hydroxymethyl content in the phenolic resin, thus lowering the reaction temperature during curing. Step b, Preparation of component A: The 20 parts of cationic waterborne polyurethane, 69 parts of phenolic resin, 8 parts of carbonate and 3 parts of foam stabilizer obtained in step a are mixed evenly to obtain component A. Cationic waterborne polyurethane modifies phenolic resin, increasing the toughness of the phenolic resin by forming a large number of hydrogen bonds. This effectively solves the problem of powder shedding caused by the brittleness of phenolic resin. It has a certain deformation capacity, and the foamed material does not crack or break after coal seam displacement or deformation under certain pressure. It will not cause gas to escape through cracks, meeting the construction requirements of underground coal mine operations and national safety production industry standards, and avoiding secondary filling and sealing. Step c, Preparation of component B: Component B is obtained by mixing 65 parts of phenolsulfonic acid, 15 parts of phosphoric acid and 20 parts of water evenly. Step d: Preparation of phenolic resin foam material: Component A and component B are mixed evenly at a volume ratio of 4:1 to obtain phenolic resin foam material. Example 3

[0022] A phenolic resin foaming material for coal mine filling and sealing includes component A and component B in a volume ratio of 4:1. Component A includes cationic aqueous polyurethane, phenolic resin, carbonate, and a foaming agent; component B includes phenol sulfonic acid, phosphoric acid, and water. By mass, component A comprises 20 parts cationic aqueous polyurethane, 69 parts phenolic resin, 8 parts carbonate, and 3 parts foaming agent; by mass, component B comprises 65 parts phenol sulfonic acid, 15 parts phosphoric acid, and 20 parts water. The cationic aqueous polyurethane is composed of aromatic polyester polyol (PPA2000) produced by Hebei Yadong Chemical Group Co., Ltd., methyl diethanolamine (MDEA) produced by Zhangjiagang Yarui Chemical Co., Ltd., diphenyltoluene diisocyanate (MDI-50) produced by Wanhua Chemical Group Co., Ltd., hydrochloric acid (HCl aqueous solution, concentration 36.5%) produced by Gaide Chemical, emulsifier OP-10 from Jiangsu Haian Petrochemical Plant, and deionized water. The phenolic resin is a first-order phenolic resin with a solid content of 72%, a viscosity of 265 mPa·s, a pH of 7.1, a free formaldehyde content of 0.38%, and a free phenol content of 4.0%. The carbonate is magnesium carbonate. The foaming agent is Tween-80.

[0023] A method for preparing a phenolic resin foam material for sealing coal mine filling includes the following steps: Step a: Preparation of cationic waterborne polyurethane: 400 parts of aromatic polyester polyol (PPA2000) and 12 parts of methyl diethanolamine (MDEA) were mixed and placed at 110℃ and a vacuum of -0.85MPa or higher for 1 hour to dehydrate. After cooling to 40℃, 70 parts of diphenyltoluene diisocyanate (MDI-50) were added dropwise and reacted at 75℃ for 1.5 hours. Then, 21 parts of phenol, the end-capping agent, were added and the temperature was increased to 85℃ at 5℃ increments of 0.5 hours. After cooling to 65℃ at 5℃ increments of 0.5 hours, the temperature was further increased. Finally, 3.7 parts of hydrochloric acid, 20 parts of emulsifier OP-10, and 526 parts of deionized water were added to emulsify and obtain a cationic waterborne polyurethane with a solid content of 50%. Cationic waterborne polyurethane has long and highly flexible chains. Phenol is used as a capping agent. Phenol can undergo a grafting reaction with phenolic resin, which distributes the polyurethane chains evenly in the phenolic resin. This not only improves the overall mechanical properties of the foam, but also reduces the hydroxymethyl content in the phenolic resin, thus lowering the reaction temperature during curing. Step b, Preparation of component A: The 20 parts of cationic waterborne polyurethane, 69 parts of phenolic resin, 8 parts of carbonate and 3 parts of foam stabilizer obtained in step a are mixed evenly to obtain component A. Cationic waterborne polyurethane modifies phenolic resin, increasing the toughness of the phenolic resin by forming a large number of hydrogen bonds. This effectively solves the problem of powder shedding caused by the brittleness of phenolic resin. It has a certain deformation capacity, and the foamed material does not crack or break after coal seam displacement or deformation under certain pressure. It will not cause gas to escape through cracks, meeting the construction requirements of underground coal mine operations and national safety production industry standards, and avoiding secondary filling and sealing. Step c, Preparation of component B: Component B is obtained by mixing 65 parts of phenolsulfonic acid, 15 parts of phosphoric acid and 20 parts of water evenly. Step d: Preparation of phenolic resin foam material: Component A and component B are mixed evenly at a volume ratio of 4:1 to obtain phenolic resin foam material.

[0024] Comparative Example A phenolic resin foaming material for coal mine filling and sealing includes component A and component B. Component A includes phenolic resin, carbonate, and a foaming agent; component B includes phenol sulfonic acid, phosphoric acid, and water. By mass, component A comprises 89 parts phenolic resin, 8 parts carbonate, and 3 parts foaming agent; by mass, component B comprises 65 parts phenol sulfonic acid, 15 parts phosphoric acid, and 20 parts water. Component A is prepared by uniformly dispersing 89 parts phenolic resin, 8 parts carbonate, and 3 parts foaming agent; component B is prepared by uniformly mixing 65 parts phenol sulfonic acid, 15 parts phosphoric acid, and 20 parts water.

[0025] The phenolic resin foam materials of Examples 1, 2, 3 and the comparative examples were tested according to the safety production industry standard (AQ / T 1090-2020) for initiation time, foaming termination time, surface drying time, maximum reaction temperature, expansion ratio, compressive strength, flame retardancy and oxygen index. The powder shedding rate was tested according to the powdering degree test standard "Rolling Abrasion Test Method for Rigid Foamed Plastics" GBT12812-1991. Table 1 shows the test results.

[0026] Table 1. Test results of Examples 1, 2, 3 and the comparative example.

[0027] As can be seen from Table 1, compared with the comparative example, in Examples 1, 2, and 3, components A and B have no flash point, the maximum reaction temperature is lower (both are less than 75°C), the expansion ratio is lower, the flame retardancy is lower, the compressive strength is greatly improved, the initiation time, the termination time, and the surface drying time are all improved, the oxygen index and the powder shedding rate are lower, especially the compressive strain when the material is broken. The compressive strain when the material is broken is about 90% after modification, while it is 68% for the unmodified material.

[0028] The decrease in maximum reaction temperature and expansion ratio is due to the reduced density of component A. This reduced density results in a lower hydroxymethyl content when cationic waterborne polyurethane is added to phenolic resin. Since the cationic waterborne polyurethane toughens the resin, it also affects the foaming rate of the phenolic resin, thus slightly reducing the foaming ratio. The decrease in flame retardancy is mainly due to the poor char-forming properties of the cationic waterborne polyurethane itself, but it still meets the industry standard for safe production (AQ / T 1090-2020). The increase in compressive strength is mainly due to the addition of flexible segments to the phenolic resin by the cationic waterborne polyurethane, which improves the toughness of the phenolic foam material. This increase in toughness is also evidenced by the deformation of the compressive strain during breakage. Furthermore, the decrease in the powder shedding rate of the phenolic foam material also demonstrates the increased toughness of the product.

[0029] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, modifications can still be made to the embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A coal mine filling sealing phenol-aldehyde resin foamed material, characterized by: The A component and the B component with a volume ratio of 4: (0.85-1.15), the A component comprising a cationic water-based polyurethane, a phenolic resin, a carbonate and a uniform foaming agent; the cationic water-based polyurethane is composed of a dihydric alcohol, methyldiethanolamine, toluene diisocyanate or diphenyl toluene diisocyanate, hydrochloric acid, an emulsifier and deionized water; the dihydric alcohol is one or more of polyether, polytetrahydrofuran diol and aromatic polyester polyol; the emulsifier is one or more of Tween-80 and OP-10; the B component comprises phenol sulfonic acid, phosphoric acid and water.

2. The coal mine sealing and filling phenolic resin foam material according to claim 1, characterized in that: The A component comprises, in mass parts: 15-30 parts of the cationic water-based polyurethane, 59-76 parts of the phenolic resin, 8 parts of the carbonate and 3 parts of the uniform foaming agent.

3. The coal mine sealing and filling phenolic resin foam material according to claim 1, characterized in that: The B component comprises, in mass parts: 65 parts of the phenol sulfonic acid, 15 parts of the phosphoric acid and 20 parts of water.

4. The coal mine sealing and filling phenolic resin foam material according to claim 1, characterized in that: The phenolic resin is a first-order phenolic resin, the solid content of the phenolic resin is 72±2%, the viscosity of the phenolic resin is 260±20 mPa·s, the pH of the phenolic resin is 7±0.3, the free formaldehyde content in the phenolic resin is ≤0.4%, and the free phenol content in the phenolic resin is ≤8%.

5. The coal mine sealing and filling phenolic resin foam material according to claim 1, characterized in that: The carbonate is magnesium carbonate.

6. The coal mine sealing and filling phenolic resin foam material according to claim 1, characterized in that: The uniform foaming agent is Tween-80.

7. A process for the preparation of a phenol-formaldehyde resin foam for sealing coal mine backfilling according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: Step a, preparing the cationic water-based polyurethane: 400 parts of polyether or polytetrahydrofuran diol or aromatic polyester polyol and 12 parts of methyldiethanolamine are mixed, then dehydrated at a temperature of 110°C and a vacuum degree of-0.85 MPa or above for 1 h, cooled to 40°C, and then 70-100 parts of toluene diisocyanate or diphenyl toluene diisocyanate is added and reacted at 75°C for 1.5 h, a blocking agent phenol is added, the temperature is raised to 85°C at a temperature raising mode of 0.5 h per 5°C, then the temperature is lowered to 65°C at a temperature lowering mode of 0.5 h per 5°C, and then 3.7 parts of hydrochloric acid, 20 parts of emulsifier OP-10 and 526-556 parts of deionized water are added to obtain the cationic water-based polyurethane; Step b, preparing the A component: 15-30 parts of the cationic water-based polyurethane, 59-76 parts of the phenolic resin, 8 parts of the carbonate and 3 parts of the uniform foaming agent obtained in step a are uniformly mixed to obtain the A component; Step c, preparing the B component: 65 parts of the phenol sulfonic acid, 15 parts of the phosphoric acid and 20 parts of water are uniformly mixed to obtain the B component; Step d, preparing the phenolic resin foaming material: The A component and the B component are uniformly mixed at a volume ratio of 4: (0.85-1.15) to obtain the phenolic resin foaming material.

8. A coal mine sealing foam material according to any one of claims 1 to 6, characterized in that: The coal mine filling sealing phenolic resin foaming material is applied to coal mine filling, construction of fireproof wall and sealing wall.

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