Functional modified polyurethane foam adsorption material and preparation process

Abstract

The present invention relates to the technical field of polyurethanes, and discloses a functional modified polyurethane foam adsorbent material and a preparation process, wherein methacrylic acid and 3-(dimethylamino)-1-propanethiol react with a benzoin dimethyl ether photoinitiator to obtain a dimethylaminothiopropionic acid intermediate, and the tertiary amine in the obtained product reacts with the epoxy in the epoxy group POSS to obtain a carboxylic acid-hydroxy quaternary ammonium salt POSS; polyethylene glycol and hexamethylene diisocyanate react with the catalysis of dibutyltin dilaurate to obtain a terminal isocyanate-based polyurethane prepolymer. Carboxylic acid-hydroxy quaternary ammonium salt POSS is added to the terminal isocyanate-based polyurethane prepolymer, foamed, and a polyurethane foam material is obtained, and the polyurethane foam material prepared by the present invention has an excellent adsorption effect.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane, in particular to a functional modified polyurethane foam adsorption material and a preparation process. Background Art

[0002] Nowadays, water pollution is a very serious problem, among which the pollution problem of heavy metal ions to the water environment is particularly serious. How to design high-efficiency and high-adsorption materials and apply them to the water environment to repair water pollution is of great significance. Polyurethane, also known as polyurethane, has two types: polyester type and polyether type. It has the advantages of low temperature resistance, aging resistance, high elasticity, etc., and is widely used in furniture, construction, home appliances and other fields. Polyurethane foam plastics are prepared by polymerization and foaming of isocyanates and hydroxyl compounds. They have excellent elasticity, elongation, softness, and chemical stability. They are widely used in cushioning packaging, cushioning materials, packaging containers and other fields. For example, the patent with patent application number CN109126743A discloses a method for preparing a polyurethane foam adsorption material, in which polyethyleneimine is modified to the foam surface with glutaraldehyde as a cross-linking agent. The polyethyleneimine functionalized polyurethane foam adsorption material prepared by the invention is an efficient and low-cost adsorption material.

[0003] Cage polysilsesquioxane (POSS) is an inorganic core linked by alternating silicon-oxygen bonds. It is a three-dimensional compound with excellent solvent resistance, high temperature resistance, weather resistance and other properties. It is widely used in adsorption materials, biomedicine, optical materials and other fields. For example, the patent application number CN109400903B reports a cage polysilsesquioxane / metal-2-aminoterephthalic acid organic framework hybrid material and its preparation method. The material prepared by the invention has excellent adsorption performance. The present invention applies the modified cage polysilsesquioxane to polyurethane materials, which have excellent adsorption performance. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies of the prior art, the present invention provides a functional modified polyurethane foam adsorption material and a preparation process, which has excellent adsorption capacity.

[0006] (II) Technical solution

[0007] A preparation process of a functional modified polyurethane foam adsorbent material, the preparation process is as follows:

[0008] (1) Epoxy POSS is dissolved in a flask containing anhydrous ethanol solution, and dimethylaminothiopropionic acid intermediate is added thereto. The reaction is refluxed for 36-72 hours, and the solvent is removed by distillation under reduced pressure. The product is washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0009] (2) Adding the terminal isocyanate polyurethane prepolymer and the carboxylic acid-hydroxy quaternary ammonium salt POSS into a reaction kettle filled with deionized water, stirring at room temperature for 50-100 seconds, pouring it into a tray, drying it for 5-15 minutes, washing it with deionized water, and drying it at 50-70° C. for 5-10 hours to obtain a polyurethane foam adsorbent material.

[0010] Preferably, in the step (1), the molar ratio of epoxy POSS to dimethylaminothiopropionic acid intermediate is 1:8-10.

[0011] Preferably, the mass of the carboxylic acid-hydroxy quaternary ammonium salt POSS in step (2) is 1-10% of the mass of the terminal isocyanate polyurethane prepolymer.

[0012] Preferably, the preparation process of the dimethylaminothiopropionic acid intermediate in step (1) is as follows:

[0013] (3) Methacrylic acid and benzoin dimethyl ether are placed in a flask containing tetrahydrofuran solution, subjected to ultrasonic treatment for 20-40 min, 3-(dimethylamino)-1-propanethiol is added thereto, stirred for 10-30 min under ultraviolet light, concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate; the reaction formula is:

[0014]

[0015] Preferably, in step (3), the molar ratio of methacrylic acid to 3-(dimethylamino)-1-propanethiol is 1:1.5-2.

[0016] Preferably, the mass of benzoin dimethyl ether in step (3) is 0.5-2% of the total molar amount of methacrylic acid and 3-(dimethylamino)-1-propanethiol.

[0017] Preferably, the preparation process of the terminal isocyanate-based polyurethane prepolymer in step (2) is as follows:

[0018] (4) Under a nitrogen atmosphere, polyethylene glycol, hexamethylene diisocyanate, and dibutyltin dilaurate catalyst are dissolved in a tetrahydrofuran solution, stirred and reacted at 60-80° C. for 2-3 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0019] Preferably, in step (4), the molar ratio of polyethylene glycol to hexamethylene diisocyanate is 1:2-2.3.

[0020] Preferably, the mass of dibutyltin dilaurate in step (4) is 0.5-1% of the total molar amount of polyethylene glycol and hexamethylene diisocyanate.

[0021] (III) Beneficial technical effects

[0022] Methacrylic acid and 3-(dimethylamino)-1-propanethiol react with each other under the action of benzoin dimethyl ether photoinitiator to obtain a dimethylaminothiopropionic acid intermediate, and the tertiary amine in the obtained product reacts with the epoxy in the epoxy POSS to obtain a carboxylic acid-hydroxy quaternary ammonium salt POSS; polyethylene glycol and hexamethylene diisocyanate react with each other under the catalysis of dibutyltin dilaurate to obtain an isocyanate-terminated polyurethane prepolymer. The carboxylic acid-hydroxy quaternary ammonium salt POSS is added to the isocyanate-terminated polyurethane prepolymer for foaming to obtain a polyurethane foam adsorption material.

[0023] The POSS used in the present invention has a large number of silicon-oxygen-silicon bonds that can electrostatically interact with metal ions, promoting the adsorption of metal ions by POSS. In order to improve the adsorption amount of POSS, the present invention introduces functional groups-quaternary ammonium salts and carboxyl groups into POSS, wherein quaternary ammonium cations can be complexed with metal ions, and can also be electrostatically interacted with negative ions, and carboxylate anions can be electrostatically adsorbed with metal ions, further improving the adsorption capacity of POSS. In addition, the polyurethane prepared by the present invention is a three-dimensional network porous structure, with high specific surface area, coexisting micro-mesopores, large pore volume and interconnected pore structure, which can promote ion diffusion in micropores, thereby promoting adsorption. The polyurethane foam adsorbent material prepared by the present invention has excellent adsorption capacity. DETAILED DESCRIPTION

[0024] The present invention is described in detail in conjunction with various embodiments, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the protection scope of the present invention.

[0025] Preparation process of epoxy POSS: At room temperature, add tetramethylammonium hydroxide to 3-glycidyl propoxy trimethoxy silane, stir and catalyze hydrolysis for 6 hours to obtain 3-glycidyl propoxy trihydroxy silane; then dissolve it in toluene solution, stir and reflux for 6 hours, wash with saturated sodium chloride solution, add anhydrous sodium sulfate to dry, and distill under reduced pressure to obtain epoxy POSS.

[0026] The structural formula is

[0027] Example 1

[0028] (1) 0.03 mol of methacrylic acid and 0.5% of the total molar amount of benzoin dimethyl ether photoinitiator are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 30 minutes. 0.06 mol of 3-(dimethylamino)-1-propanethiol is added thereto, and the mixture is stirred for 20 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

[0029] (2) 0.04 mol of epoxy POSS was dissolved in a flask containing anhydrous ethanol solution, and 0.4 mol of dimethylaminothiopropionic acid intermediate was added thereto. The reaction was refluxed for 48 h, and the solvent was removed by distillation under reduced pressure. The solution was washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0030] (3) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.115 mol of hexamethylene diisocyanate, and 1% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 2 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0031] (4) 200 g of terminal isocyanate polyurethane prepolymer and 2 g of carboxylic acid-hydroxy quaternary ammonium salt POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 80 seconds, poured into a tray, dried for 12 minutes, washed with deionized water, and dried at 60° C. for 8 hours to obtain a polyurethane foam adsorbent material.

[0032] Example 2

[0033] (1) 0.03 mol of methacrylic acid and 1% of the total molar amount of benzoin dimethyl ether photoinitiator are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 30 minutes. 0.05 mol of 3-(dimethylamino)-1-propanethiol is added thereto, and the mixture is stirred for 20 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

[0034] (2) 0.04 mol of epoxy POSS was dissolved in a flask containing anhydrous ethanol solution, and 0.4 mol of dimethylaminothiopropionic acid intermediate was added thereto. The reaction was refluxed for 72 h, and the solvent was removed by distillation under reduced pressure. The solution was washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0035] (3) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.115 mol of hexamethylene diisocyanate, and 0.5% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 2 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0036] (4) 200 g of terminal isocyanate polyurethane prepolymer and 6 g of carboxylic acid-hydroxy quaternary ammonium salt POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 60 seconds, poured into a tray, dried for 10 minutes, washed with deionized water, and dried at 60° C. for 8 hours to obtain a polyurethane foam adsorbent material.

[0037] Example 3

[0038] (1) 0.03 mol of methacrylic acid and 0.1% of the total molar amount of benzoin dimethyl ether photoinitiator are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 30 minutes. 0.045 mol of 3-(dimethylamino)-1-propanethiol is added thereto, and stirred for 30 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

[0039] (2) 0.04 mol of epoxy POSS was dissolved in a flask containing anhydrous ethanol solution, to which 0.35 mol of dimethylaminothiopropionic acid intermediate was added, and the reaction was refluxed for 72 h. The solvent was removed by distillation under reduced pressure, washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0040] (3) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.1 mol of hexamethylene diisocyanate, and 0.6% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 3 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0041] (4) 200 g of terminal isocyanate polyurethane prepolymer and 10 g of carboxylic acid-hydroxy quaternary ammonium salt POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 100 s, poured into a tray, dried for 5 min, washed with deionized water, and dried at 60 ° C for 8 h to obtain a polyurethane foam adsorbent material.

[0042] Example 4

[0043] (1) 0.03 mol of methacrylic acid and 0.5% of the total molar amount of benzoin dimethyl ether photoinitiator are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 30 minutes. 0.045 mol of 3-(dimethylamino)-1-propanethiol is added thereto, and stirred for 30 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

[0044] (2) 0.04 mol of epoxy POSS was dissolved in a flask containing anhydrous ethanol solution, and 0.32 mol of dimethylaminothiopropionic acid intermediate was added thereto. The reaction was refluxed for 48 h, and the solvent was removed by distillation under reduced pressure. The solution was washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0045] (3) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.115 mol of hexamethylene diisocyanate, and 0.8% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 3 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0046] (4) 200 g of terminal isocyanate polyurethane prepolymer and 15 g of carboxylic acid-hydroxy quaternary ammonium salt POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 50 seconds, poured into a tray, dried for 10 minutes, washed with deionized water, and dried at 70° C. for 10 hours to obtain a polyurethane foam adsorbent material.

[0047] Example 5

[0048] (1) 0.03 mol of methacrylic acid and 1% of the total molar amount of benzoin dimethyl ether photoinitiator are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 20 minutes. 0.06 mol of 3-(dimethylamino)-1-propanethiol is added thereto, and stirred for 20 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

[0049] (2) 0.04 mol of epoxy POSS was dissolved in a flask containing anhydrous ethanol solution, and 0.4 mol of dimethylaminothiopropionic acid intermediate was added thereto. The reaction was refluxed for 72 h, and the solvent was removed by distillation under reduced pressure. The solution was washed with isopropanol, recrystallized with acetone, and dried to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS.

[0050] (3) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.1 mol of hexamethylene diisocyanate, and 1% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 3 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0051] (4) 200 g of terminal isocyanate polyurethane prepolymer and 20 g of carboxylic acid-hydroxy quaternary ammonium salt POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 50 seconds, poured into a tray, dried for 15 minutes, washed with deionized water, and dried at 60° C. for 8 hours to obtain a polyurethane foam adsorbent material.

[0052] Comparative Example 1

[0053] (1) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.115 mol of hexamethylene diisocyanate, and 1% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 2 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0054] (2) 200 g of isocyanate-terminated polyurethane prepolymer and 2 g of epoxy POSS were added to a reaction kettle filled with deionized water, stirred at room temperature for 80 seconds, poured into a tray, dried for 12 minutes, washed with deionized water, and dried at 60° C. for 8 hours to obtain a polyurethane foam material.

[0055] Comparative Example 2

[0056] (1) Under a nitrogen atmosphere, 0.05 mol of polyethylene glycol, 0.115 mol of hexamethylene diisocyanate, and 1% of the total molar amount of dibutyltin dilaurate catalyst were dissolved in a tetrahydrofuran solution, stirred at 70° C. for 2 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

[0057] (2) 200 g of the isocyanate-terminated polyurethane prepolymer was added to a reaction kettle filled with deionized water, stirred at room temperature for 80 seconds, poured into a tray, dried for 12 minutes, washed with deionized water, and dried at 60° C. for 8 hours to obtain a polyurethane foam material.

[0058] 20 mg of polyurethane foam material was placed in an iodine volumetric flask, 50 mL of a divalent copper ion operating solution with a mass concentration of 30 μg / mL was added, the mixture was shaken for 3 h, filtered, and the divalent copper ion mass concentration B of the filtrate was determined by atomic absorption spectrometry.

[0059] Adsorption rate C = [(AB) / A] × 100%.

[0060] A is the initial mass concentration of the adsorbed solution, μg / mL. B is the equilibrium mass concentration of the adsorbed solution, μg / mL.

[0061]

[0062] The polyurethane foam material of Example 3 has the best adsorption effect on divalent copper ions, while the adsorption effects of Comparative Examples 1 and 2 are relatively poor. This is because Examples 1-5 contain carboxylic acid-hydroxy quaternary ammonium salt POSS, in which the carboxylate cations can produce electrostatic adsorption with divalent copper ions, and the nitrogen and silicon-oxygen-silicon bonds in the quaternary ammonium salt can produce coordination chelation with divalent copper ions. In addition, the huge cross-linked network structure has a large specific surface area and mesopores, which can also produce adsorption effects on divalent copper ions. Therefore, the adsorption effects of Examples 1-5 are better, and in Comparative Example 1, only POSS is added, and its effect is better than the adsorption effect of Comparative Example 2 without adding any substance.

[0063] The above disclosure is only a few specific embodiments of the present application, but the present application is not limited thereto. Any changes made by any technician in this field to the formula, process, implementation method, etc. on the basis of the present invention should be within the scope of protection of the present application.

Claims

1. A process for preparing a functional modified polyurethane foam adsorbent material, characterized in that: The preparation process is as follows: (1) dissolving epoxy POSS in a flask containing anhydrous ethanol solution, adding dimethylaminothiopropionic acid intermediate thereto, reflux reaction for 36-72h, removing the solvent by distillation under reduced pressure, washing with isopropanol, recrystallizing with acetone, and drying to obtain carboxylic acid-hydroxy quaternary ammonium salt POSS; (2) Adding the terminal isocyanate polyurethane prepolymer and the carboxylic acid-hydroxy quaternary ammonium salt POSS into a reaction kettle filled with deionized water, stirring at room temperature for 50-100 seconds, pouring it into a tray, drying it for 5-15 minutes, washing it with deionized water, and drying it at 50-70° C. for 5-10 hours to obtain a polyurethane foam adsorbent material.

2. The preparation process of the functional modified polyurethane foam adsorbent material according to claim 1, characterized in that: In the step (1), the molar ratio of epoxy POSS to dimethylaminothiopropionic acid intermediate is 1:8-10.

3. The preparation process of the functional modified polyurethane foam adsorbent material according to claim 1, characterized in that: The mass of the carboxylic acid-hydroxy quaternary ammonium salt POSS in the step (2) is 1-10% of the mass of the terminal isocyanate polyurethane prepolymer.

4. The preparation process of the functional modified polyurethane foam adsorbent material according to claim 1, characterized in that: The preparation process of the dimethylaminothiopropionic acid intermediate in step (1) is as follows: (3) Methacrylic acid and benzoin dimethyl ether are placed in a flask containing tetrahydrofuran solution, and ultrasonicated for 20-40 minutes. 3-(dimethylamino)-1-propanethiol is added thereto, and stirred for 10-30 minutes under ultraviolet light. The mixture is concentrated, washed with petroleum ether, and dried to obtain a dimethylaminothiopropionic acid intermediate.

5. The process for preparing the functionalized modified polyurethane foam adsorbent material according to claim 4, characterized in that: In the step (3), the molar ratio of methacrylic acid to 3-(dimethylamino)-1-propanethiol is 1:1.5-2.

6. The process for preparing the functionalized modified polyurethane foam adsorbent material according to claim 4, characterized in that: The mass of benzoin dimethyl ether in step (3) is 0.5-2% of the total molar mass of methacrylic acid and 3-(dimethylamino)-1-propanethiol.

7. The process for preparing the functionalized modified polyurethane foam adsorbent material according to claim 1, characterized in that: The preparation process of the terminal isocyanate-based polyurethane prepolymer in step (2) is as follows: (4) Under a nitrogen atmosphere, polyethylene glycol, hexamethylene diisocyanate, and dibutyltin dilaurate catalyst are dissolved in a tetrahydrofuran solution, stirred and reacted at 60-80° C. for 2-3 h, cooled to room temperature, concentrated, and washed with ethanol to obtain an isocyanate-terminated polyurethane prepolymer.

8. The process for preparing the functionalized modified polyurethane foam adsorbent material according to claim 7, characterized in that: In the step (4), the molar ratio of polyethylene glycol to hexamethylene diisocyanate is 1:2-2.

3.

9. The process for preparing the functionalized modified polyurethane foam adsorbent material according to claim 7, characterized in that: The mass of dibutyltin dilaurate in step (4) is 0.5-1% of the total molar mass of polyethylene glycol and hexamethylene diisocyanate.

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