Tailing treatment method and application of novel polymer curing agent

Abstract

The invention relates to the technical field of materials, in particular to a tailing treatment method and application of a novel polymer curing agent, and a copolymer composite material has good water resistance, aging resistance and mechanical property. The curing speed is high, and the curing time can be shortened to be within 24 hours under proper conditions; the curing strength is high, and the compressive strength of a cured tailing sample is remarkably improved; and the permeability resistance is good, permeation of water in the tailings is effectively reduced, and leaching of harmful substances is reduced. The paint is environment-friendly, low in VOC (volatile organic compound) emission, biodegradable and pollution-free to the environment.

Description

Technical Field

[0001] The invention relates to the field of polymer materials, and in particular to a tailings treatment method and application of a novel polymer curing agent. Background Art

[0002] Tailings are the remaining parts of the ore with low content of useful components after selection, and their treatment has always been an important issue facing the mining industry. Traditional tailings treatment methods have many limitations, such as poor stability of the treated tailings and easy environmental pollution. With the increasing environmental protection requirements and the emphasis on the effective use of resources, it is imperative to develop new and efficient tailings treatment methods. Polymer curing agents have been widely used in other fields such as coatings, adhesives, composite materials, etc., and have shown significant advantages in improving material properties. Given that they can change the physical and chemical properties of substances through chemical reactions, the application of polymer curing agents in tailings treatment has great potential. It can be expected that the stability of tailings can be improved through curing and the risk of environmental pollution can be reduced. Although attempts have been made to apply polymer curing agents to tailings treatment, there are still some problems with the existing technology. For example, the selection of curing agents lacks specificity and does not fully consider the differences in the composition and properties of tailings; the performance of curing agents is not ideal and cannot effectively meet the complex requirements of tailings treatment; in the curing process, improper treatment of tailings affects the curing effect and may also cause new environmental problems. Summary of the invention

[0003] Based on this, the present invention provides a method and application of the tail payment of a new polymer curing agent. Specifically, a new polymer curing agent includes: an amino-epoxy copolymer (P (Am - Ep)), which is prepared by reacting an amine compound and an epoxy compound in a molar ratio of 1:2, wherein the amine compound is diethylenetriamine, and the epoxy compound is bisphenol A epoxy resin.

[0004] Furthermore, the catalyst used in the preparation process of the copolymer is triphenylphosphine, and its dosage is 1% of the total mass of the reactants. The reaction solvent is toluene, the reaction temperature is 90° C., the reaction time is 5 hours, and a uniform stirring device is used during the reaction.

[0005] Furthermore, in the tailings treatment method of the amino-epoxy copolymer (P (Am - Ep)), when the treated P (Am - Ep) copolymer is applied to tailings treatment, it is mixed with the tailings in a mass ratio of 1:20, and the curing agent is evenly distributed in the tailings by stirring and the like, and then a curing reaction is carried out under suitable conditions.

[0006] The present invention also provides an epoxy resin curing agent of the amino-epoxy copolymer (P (Am - Ep)), wherein the mass ratio of the amino-epoxy copolymer (P (Am - Ep)) to the epoxy resin is 1:3, and the epoxy resin curing agent further comprises a pigment, a filler and an additive.

[0007] On the other hand, the present invention also provides a polyester-isocyanate copolymer (P (Pe-Iso)), which is prepared by synthesizing a polyester prepolymer from adipic acid and ethylene glycol in a molar ratio of 1:1.5, and then reacting the polyester prepolymer with toluene diisocyanate in a mass ratio of 3:2. The catalyst used in the reaction is tetrabutyl titanate, and its amount is 0.5% of the total mass of the reactants.

[0008] Furthermore, in the polyester-isocyanate copolymer (P (Pe-Iso)), the synthesis temperature of the polyester prepolymer is 180°C, the reaction time is 6 hours, and the segmented temperature control technology is adopted during the synthesis process; the reaction temperature of the polyester prepolymer and toluene diisocyanate is 70°C, and the reaction time is 4 hours.

[0009] Furthermore, the tailings treatment method of the polyester-isocyanate copolymer (P (Pe-Iso)) is to mix it with the tailings in a mass ratio of 1:20, and evenly distribute the curing agent in the tailings by stirring, etc., and then carry out a curing reaction under suitable conditions, thereby improving the stability of the tailings and reducing the risk of leaching of harmful substances in the tailings.

[0010] Furthermore, the invention also provides a curing agent containing the polyester-isocyanate copolymer (P (Pe-Iso)), characterized in that the mass ratio of the polyester-isocyanate copolymer (P (Pe-Iso)) to the polyurethane resin is 1:4, and it also contains a curing accelerator and a filler.

[0011] The present invention also provides an acrylate-siloxane copolymer (P (Ac - Si)), which is prepared by polymerizing methyl methacrylate in the presence of an initiator benzoyl peroxide (accounting for 2% of the total weight of the monomer) and a solvent ethyl acetate at 80° C. for 3 hours to obtain an acrylate prepolymer, and then reacting the acrylate prepolymer with γ-glycidyloxypropyltrimethoxysilane at a mass ratio of 4:1 at 80° C. for 3 hours, and adopting an inert gas protection technology during the reaction process.

[0012] Furthermore, the tailings treatment method of the acrylate-siloxane copolymer (P (Ac - Si)) is as follows: mixing it with tailings in a mass ratio of 1:20, uniformly distributing the curing agent in the tailings by stirring, etc., and then performing a curing reaction under suitable conditions.

[0013] Beneficial technical effects: The curing speed is fast. Under suitable conditions, the curing time can be shortened to less than 24 hours. The curing strength is high, and the compressive strength of the cured tailings samples is significantly improved. The impermeability is good, which effectively reduces the penetration of water in the tailings and reduces the leaching of harmful substances. It is environmentally friendly, has low VOC emissions, is biodegradable, and has no pollution to the environment. DETAILED DESCRIPTION Example 1

[0014] P (Am - Ep) is designed and synthesized based on the demand for optimizing the performance of polymer curing agents. By introducing amine and epoxy groups into the same copolymer, the curing process can be regulated by utilizing the reactivity of amine and epoxy groups. Group action mechanism: Amine group: Amine groups have high reactivity and can react with a variety of functional groups. During the curing process, amine groups can react rapidly with epoxy groups in matrix resins such as epoxy resins to form a cross-linked structure, thereby achieving curing. The presence of amine groups can accelerate the curing speed and improve the curing efficiency. Epoxy group: Epoxy groups can undergo ring-opening reactions with amine groups under certain conditions, and self-polymerization reactions can also occur between epoxy groups. By adjusting the ratio of amine groups to epoxy groups, the cross-linking density and network structure of the cured product can be controlled, and then the performance of the cured product can be adjusted. For example, appropriately increasing the content of epoxy groups can increase the hardness and strength of the cured product, while increasing the content of amine groups can increase the flexibility of the cured product. First, select suitable amine compounds (such as diethylenetriamine) and epoxy compounds (such as bisphenol A epoxy resin) as raw materials. The amine compound and the epoxy compound are added to the reaction vessel in a molar ratio of 1:2, and a catalyst triphenylphosphine accounting for 1% of the total mass of the reactants and an appropriate amount of solvent toluene are added. The reaction is carried out at 90°C for 5 hours. During the reaction, a uniform stirring device is used to ensure that the reaction proceeds uniformly. After the reaction is completed, the solvent is removed by reduced pressure distillation to obtain a P (Am - Ep) copolymer.

[0015] Introducing a uniform stirring device during the reaction process can allow the reactants to fully contact, improve the uniformity and conversion rate of the reaction, and thus obtain a copolymer with higher purity and more stable performance.

[0016] In the synthesis process of P (Am - Ep), there may be tails such as unreacted amine compounds and epoxy compounds. For these tails, the extraction method can be used to treat them. Choose ethanol as the extractant, dissolve the reaction product in toluene, then add ethanol to the toluene solution, stir evenly and let it stand for stratification. Take out the lower ethanol phase, repeat the extraction operation 3 times to remove the tails. Finally, dry and purify the treated product to obtain a high-purity P (Am - Ep) copolymer.

[0017] P (Am - Ep) copolymer can be used as a polymer curing agent in epoxy resin curing agent. In the preparation process of the curing agent, P (Am - Ep) copolymer and epoxy resin are mixed in a mass ratio of 1:3, and appropriate amounts of pigments (such as titanium dioxide), fillers (such as calcium carbonate) and additives (such as leveling agents, defoamers, etc.) are added. After stirring evenly, a high-performance epoxy resin curing agent can be obtained. The curing agent has the advantages of fast curing speed, high hardness, and strong adhesion.

[0018] Comparative synergy test (compared with existing technology)

[0019] Example 2 P (Pe - Iso) is designed and synthesized to improve the flexibility and weather resistance of polymer curing agents. The polyester segment and the isocyanate group are combined together, and the flexibility of the polyester and the reactivity of the isocyanate group are used to prepare a curing agent with excellent performance. Polyester segment: The polyester segment has good flexibility and elasticity, which can give the cured product good impact resistance and bending properties. During the curing process, the polyester segment can be embedded in the network structure of the cured product as a flexible segment, increasing the mobility of the molecular chain, thereby improving the flexibility of the cured product. Isocyanate group: The isocyanate group has high reactivity and can react with a variety of compounds containing active hydrogen. When reacting with the matrix resin, the isocyanate group can react with groups such as hydroxyl and amine to form a cross-linked structure to achieve curing. At the same time, the isocyanate group can also react with moisture in the air to form a urea bond, further enhancing the performance of the cured product.

[0020] First, synthesize the polyester prepolymer. Adipic acid and ethylene glycol were selected as raw materials, and the polycondensation reaction was carried out at 180°C under the action of the catalyst tetrabutyl titanate (accounting for 0.5% of the total mass of the reactants) in a molar ratio of 1:1.5, and the reaction time was 6 hours. During the reaction process, the segmented temperature control technology was adopted, that is, the heating rate was slow in the early stage of the reaction, the temperature was kept stable in the middle stage, and the temperature was gradually lowered in the later stage to improve the uniformity of the molecular weight distribution of the polyester prepolymer. After obtaining the polyester prepolymer, the polyester prepolymer was mixed with an isocyanate compound (such as toluene diisocyanate) in a mass ratio of 3:2, and reacted at 70°C for 4 hours to obtain a P (Pe-Iso) copolymer. The segmented temperature control technology can better control the synthesis process of the polyester prepolymer, make the molecular weight distribution more uniform, and thus improve the performance stability of the copolymer.

[0021] The tails produced during the synthesis of P (Pe - Iso) copolymers can be treated by thin film evaporation. The reaction product is passed through a thin film evaporator under reduced pressure, the evaporator temperature is controlled at 120°C, and the vacuum degree is -0.09MPa, so that the tails are volatilized, while the copolymer remains at the bottom of the evaporator. After thin film evaporation treatment, a P (Pe - Iso) copolymer with higher purity can be obtained.

[0022] P (Pe - Iso) copolymer can be used in the field of curing agents. It is mixed with a suitable curing agent matrix resin (such as polyurethane resin), the mass ratio of P (Pe - Iso) copolymer to polyurethane resin is 1:4, and curing accelerators (such as dibutyltin dilaurate), fillers (such as white carbon black) and other additives are added to prepare high-performance adhesives. The curing agent has good flexibility, bonding strength and weather resistance.

[0023] Comparative synergy test (compared with existing technology)

[0024] Example 3 P (Ac - Si) is designed and synthesized to improve the water resistance and aging resistance of polymer curing agents. The acrylate group and the siloxane group are combined together to prepare a high-performance curing agent by utilizing the fast curing characteristics of acrylate and the low surface energy and weather resistance of siloxane. Acrylate group: The acrylate group has the characteristics of fast curing and can form a cross-linked structure in a short time. During the curing process, the acrylate group can be quickly cured through free radical polymerization, providing the initial strength and hardness of the cured product. At the same time, the acrylate group can also copolymerize with other functional groups to further optimize the performance of the cured product. Siloxane group: The siloxane group has low surface energy and good weather resistance. The siloxane group can form a hydrophobic layer on the surface of the cured product to prevent water penetration and improve the water resistance of the cured product. In addition, the siloxane group can also absorb ultraviolet rays, reduce the damage of ultraviolet rays to the cured product, and improve the aging resistance of the cured product.

[0025] First, an acrylate prepolymer was synthesized. Methyl methacrylate was selected as the monomer, and a polymerization reaction was carried out at 80°C for 3 hours in the presence of an initiator benzoyl peroxide (accounting for 2% of the total weight of the monomer) and a solvent ethyl acetate to obtain an acrylate prepolymer. Then, the acrylate prepolymer was mixed with a siloxane-containing compound (such as γ-glycidyloxypropyltrimethoxysilane) in a mass ratio of 4:1 and reacted at 80°C for 3 hours. During the reaction, an inert gas protection technology was used to prevent oxygen from interfering with the reaction and improve the selectivity and conversion rate of the reaction. After the reaction, a P (Ac-Si) copolymer was obtained. The inert gas protection technology can effectively avoid the influence of oxygen on the reaction and improve the purity and performance stability of the copolymer.

[0026] The tails produced during the synthesis of P (Ac - Si) copolymers can be treated by activated carbon adsorption. The reaction product and activated carbon are mixed in a mass ratio of 10:1, stirred for 2 hours, and then the activated carbon is filtered to remove the tails. Activated carbon can adsorb unreacted monomers and impurities to improve the purity of the copolymer. P (Ac -Si) copolymers can be used in the field of composite materials. It is compounded with fiber reinforcement materials (such as glass fiber) and matrix resins (such as unsaturated polyester resins). The mass ratio of P (Ac - Si) copolymer, glass fiber and unsaturated polyester resin is 1:3:6 to prepare a high-performance composite material. The composite material has good water resistance, aging resistance and mechanical properties.

[0027] Comparative synergy test (compared with existing technology)

[0028] The copolymer composite material has good water resistance, aging resistance and mechanical properties. It has fast curing speed. Under suitable conditions, the curing time can be shortened to less than 24 hours. It has high curing strength. The compressive strength of the cured tailings sample is significantly improved. It has good impermeability, effectively reducing the penetration of water in the tailings and reducing the leaching of harmful substances. It is environmentally friendly, has low VOC emissions, is biodegradable, and has no pollution to the environment.

Claims

1. An amino-epoxy copolymer (P (Am - Ep)), characterized in that: The amine compound and the epoxy compound are reacted in a molar ratio of 1:2, wherein the amine compound is diethylenetriamine and the epoxy compound is bisphenol A epoxy resin.

2. The amino-epoxy copolymer (P (Am - Ep)) according to claim 1, characterized in that The catalyst used in the preparation process of the copolymer is triphenylphosphine, and its dosage is 1% of the total mass of the reactants. The reaction solvent is toluene, the reaction temperature is 90° C., the reaction time is 5 hours, and a uniform stirring device is used during the reaction.

3. The tailings treatment method of the amino-epoxy copolymer (P (Am - Ep)) according to claim 1 or 2, characterized in that: When the treated P (Am - Ep) copolymer is used for tailings treatment, it is mixed with the tailings in a mass ratio of 1:20, and the curing agent is evenly distributed in the tailings by stirring, and then a curing reaction is carried out under suitable conditions.

4. An epoxy resin curing agent containing the amino-epoxy copolymer (P (Am-Ep)) according to any one of claims 1 to 2, characterized in that: The mass ratio of the amino-epoxy copolymer (P (Am - Ep)) to the epoxy resin is 1:3, and the copolymer also contains pigments, fillers and additives.

5. A polyester-isocyanate copolymer (P (Pe-Iso)), characterized in that The polyester prepolymer is synthesized from adipic acid and ethylene glycol in a molar ratio of 1:1.5, and then the polyester prepolymer is reacted with toluene diisocyanate in a mass ratio of 3:

2. The catalyst used in the reaction is tetrabutyl titanate, and its amount is 0.5% of the total mass of the reactants.

6. The polyester-isocyanate copolymer (P (Pe-Iso)) according to claim 5, characterized in that The synthesis temperature of the polyester prepolymer is 180° C., the reaction time is 6 hours, and the segmented temperature control technology is adopted during the synthesis process; the reaction temperature of the polyester prepolymer and toluene diisocyanate is 70° C., and the reaction time is 4 hours.

7. The method for treating tailings of polyester-isocyanate copolymer (P (Pe-Iso)) according to claim 5 or 6, characterized in that: Mix it with the tailings in a mass ratio of 1:20, and evenly distribute the curing agent in the tailings through stirring and other means, and then carry out the curing reaction under suitable conditions to improve the stability of the tailings and reduce the risk of leaching of harmful substances in the tailings.

8. A curing agent containing the polyester-isocyanate copolymer (P (Pe-Iso)) according to any one of claims 5 to 6, characterized in that: The polyester-isocyanate copolymer (P (Pe-Iso)) has a mass ratio of 1:4 to the polyurethane resin, and further comprises a curing accelerator and a filler.

9. An acrylate-siloxane copolymer (P (Ac - Si)), characterized in that: The acrylate prepolymer is obtained by polymerizing methyl methacrylate in the presence of an initiator benzoyl peroxide (accounting for 2% of the total weight of the monomer) and a solvent ethyl acetate at 80°C for 3 hours, and then the acrylate prepolymer is reacted with γ-glycidyloxypropyltrimethoxysilane at a mass ratio of 4:1 at 80°C for 3 hours. Inert gas protection is used during the reaction.

10. The acrylate-siloxane copolymer (P (Ac - Si)) according to claim 9, characterized in that The tailings treatment method of the copolymer is: mixing the copolymer with tailings at a mass ratio of 1:20, uniformly distributing the curing agent in the tailings by stirring or the like, and then performing a curing reaction under suitable conditions.

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