Preparation method, product and application of polyethyleneimine polymer hydrogel based on imine bond and borate bond

Abstract

The invention relates to the technical field of adsorption of VOCs (Volatile Organic Compounds) by polymer gel, in particular to a preparation method, a product and application of polyethyleneimine polymer hydrogel based on imine bonds and borate bonds. The preparation method comprises the following steps: dissolving polyethyleneimine and 4-acetylphenylboronic acid in absolute ethyl alcohol, refluxing at 80 DEG C for 56h, and freeze-drying to obtain a target product A; dissolving the target product A in a sodium hydroxide solution to obtain a solution S2; dispersing hydrotalcite in dimethyl sulfoxide, and then adding a tannic acid aqueous solution to obtain a solution S3; adding a monomer into the solution of S3, uniformly mixing, adding the aqueous solution of B, adding the solution of S2, an initiator and lithium chloride, uniformly mixing, and performing ultraviolet radiation to obtain the polyethyleneimine polymer hydrogel based on the imine bond and the borate bond. The method disclosed by the invention is mild in required conditions, strong in operability and good in reproducibility, and the obtained product is stable, economical and low in cost.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer gel adsorption of VOCs, and in particular to a preparation method, product and application of a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds. Background Art

[0002] Volatile organic compounds (VOCs) are a general term for a large class of air pollutants. Some types of VOCs are non-toxic, but many VOCs can cause great damage to human health and environmental safety. VOCs not only directly damage human health and cause malignant diseases such as leukemia and cancer, but also produce a variety of pollutants through atmospheric photochemical reactions, polluting the environment. Therefore, it is very important to develop adsorbents with adsorption properties for VOCs.

[0003] In the past decades, gels have been used as an effective platform for oil spill or water separation, and in many cases have achieved the removal of pollutants (e.g., metal ions) and phase separation. Many absorbents, such as porous aromatic frameworks, metal organic frameworks, mesoporous organosilicon nanoparticles or periodic mesoporous organosilicon, covalent organic frameworks, nanoparticles, carbon nanotubes, zeolites, aerogels and functional liquids have been used for gas absorption. However, efficient absorption and separation of volatile organic compounds (VOCs) in the environment has always been a challenge for chemistry and industry. Summary of the invention

[0004] Based on the above content, the present invention provides a preparation method, product and application of a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention is a method for preparing a polyethyleneimine polymer hydrogel based on an imine bond and a borate ester bond, comprising the following steps:

[0007] Dissolve polyethyleneimine and 4-acetophenylboronic acid in anhydrous ethanol to obtain S1 solution;

[0008] The S1 solution was refluxed at 80° C. for 56 h and then freeze-dried to obtain the target product A;

[0009] The target product A is dissolved in a sodium hydroxide solution to obtain a S2 solution;

[0010] Dispersing hydrotalcite in dimethyl sulfoxide, and then adding tannic acid aqueous solution to obtain S3 solution;

[0011] Add the monomer to the S3 solution and mix well, then add the aqueous solution of B, then add the S2 solution, initiator and lithium chloride, mix well and then irradiate with ultraviolet light to obtain the polyethyleneimine polymer hydrogel based on imine bonds and borate bonds;

[0012] The substance B is one of polyvinyl alcohol, sodium alginate, guar gum, and hydroxypropyl guar gum;

[0013] The monomer is one of sodium acrylate, acrylamide, acrylic acid, hydroxyethyl methacrylate, N-(2-hydroxyethyl)acrylamide, methacryloyloxyethyl trimethylammonium chloride, and 2-(dimethylamino)ethyl acrylate.

[0014] The second technical solution of the present invention is a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds prepared according to the above-mentioned preparation method.

[0015] The third technical solution of the present invention is the application of the above-mentioned polyethyleneimine polymer hydrogel based on imine bonds and borate bonds in the adsorption of VOCs.

[0016] Since polyethyleneimine is present in the polymer network of the polymer hydrogel of the present invention, the polymer hydrogel can bind heavy metal ions, dyes, gases and organic compounds in the process of pollutant removal, thereby becoming an excellent adsorbent. The gel obtained by containing polyethyleneimine can selectively absorb volatile organic compounds, and some can convert gases into solutions. The process produces two phases, namely a liquid phase (organic solvent) and a solid phase (gel), which are easy to separate. Compared with other adsorbent materials, gel has the advantages of simplicity, high adsorption and easy recovery. Based on the above reasons, the polymer hydrogel of the present invention has a good application prospect in environmental remediation.

[0017] The present invention discloses the following technical effects:

[0018] The method of the invention requires mild conditions, has strong operability, good reproducibility, and the obtained product is stable, economical and low in cost.

[0019] The invention constructs a polyethyleneimine polymer hydrogel with imine bonds and borate bonds to adsorb VOCs.

[0020] The polymer hydrogel prepared by the invention can selectively absorb volatile gases such as acetone, methanol, ethanol and acetonitrile. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a diagram of the adsorption device in Example 1 of the present invention.

[0023] Figure 2 This is a graph showing the adsorption of acetone, methanol, ethanol and acetonitrile at different adsorption times by the polymer hydrogel prepared in Example 1 of the present invention.

[0024] Figure 3 These are photos of the polymer hydrogel prepared in Example 1 of the present invention before adsorbing VOCS (acetone, methanol, ethanol, acetonitrile, carbon tetrachloride, dichloromethane, cyclohexanol, ethyl acetate, benzene, toluene, chlorobenzene, aniline, and n-hexane).

[0025] Figure 4 Photos of the polymer hydrogel prepared in Example 1 of the present invention adsorbing acetone, methanol, ethanol and acetonitrile for different time periods. DETAILED DESCRIPTION

[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0027] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0028] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0029] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0030] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0031] The "room temperature" or "normal temperature" mentioned in the present invention, unless otherwise specified, means 0-30°C.

[0032] The first aspect of the present invention provides a method for preparing a boronate bond-based polyethyleneimine polymer hydrogel, comprising the following steps:

[0033] Dissolve polyethyleneimine and 4-acetophenylboronic acid in anhydrous ethanol to obtain S1 solution;

[0034] The S1 solution was refluxed at 80° C. for 56 h and then freeze-dried to obtain the target product A;

[0035] The target product A is dissolved in a sodium hydroxide solution to obtain a S2 solution;

[0036] Dispersing hydrotalcite in dimethyl sulfoxide, and then adding tannic acid aqueous solution to obtain S3 solution;

[0037] Add the monomer to the S3 solution and mix well, then add the aqueous solution of B, then add the S2 solution, initiator and lithium chloride, mix well and then irradiate with ultraviolet light to obtain the polyethyleneimine polymer hydrogel based on imine bonds and borate bonds;

[0038] The substance B is one of polyvinyl alcohol, sodium alginate, guar gum, and hydroxypropyl guar gum;

[0039] The monomer is one of sodium acrylate, acrylamide, acrylic acid, hydroxyethyl methacrylate, N-(2-hydroxyethyl)acrylamide, methacryloyloxyethyl trimethylammonium chloride, and 2-(dimethylamino)ethyl acrylate.

[0040] The synthetic route of target product A is as follows:

[0041]

[0042] The dissolving or mixing method in the present invention can be ultrasonication for 2-3 minutes at room temperature.

[0043] In a preferred embodiment of the present invention, the polyethyleneimine is linear polyethyleneimine or branched polyethyleneimine; the molecular weight of the polyethyleneimine is 10000.

[0044] In a preferred embodiment of the present invention, the initiator is 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone.

[0045] In a preferred embodiment of the present invention, the mass volume ratio of the hydrotalcite, dimethyl sulfoxide, tannic acid, water, monomer, substance A, substance B, initiator and lithium chloride is 0.01g: 0.1mL: 0.005g: 0.6mL: (0.8-1.0)g: 0.005g: 0.01g: 0.01g.

[0046] In a preferred embodiment of the present invention, the concentration of the tannic acid aqueous solution is 5 wt %.

[0047] In a preferred embodiment of the present invention, the concentration of the aqueous solution of substance B is 1 wt %.

[0048] In a preferred embodiment of the present invention, the power of the ultraviolet irradiation is 72W and the time is 80 seconds.

[0049] The second aspect of the present invention provides a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds prepared according to the above preparation method.

[0050] The third aspect of the present invention provides an application of the above-mentioned polyethyleneimine polymer hydrogel based on imine bonds and borate bonds in the adsorption of VOCs.

[0051] The technical solutions described in the present invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are purchased from commercial channels or have been disclosed.

[0052] The molecular weight of polyethyleneimine used in the present invention is 10000

[0053] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0054] Example 1

[0055] 5 g of polyethyleneimine and 2 g of 4-acetophenylboronic acid were weighed and dissolved in 20 mL of anhydrous ethanol, refluxed at 80° C. for 56 h, and then freeze-dried to obtain the target product A. 0.21 g of the target product A was dissolved in 0.5 mL of 1 mol / L sodium hydroxide to obtain an alkaline solution of A.

[0056] 0.01 g of hydrotalcite was weighed and dissolved in 0.1 mL of dimethyl sulfoxide, and dispersed uniformly at room temperature. Then, 0.1 mL of 5 wt% tannic acid was added and dissolved by ultrasonic vibration. Then, 0.9 g of N-(2-hydroxyethyl)acrylamide was added thereto and mixed uniformly. Then, 0.5 g of 1 wt% sodium alginate and 0.1 mL of alkaline solution were added and stirred uniformly. Then, 0.01 g of 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone and 0.01 g of lithium chloride were added. After irradiation with ultraviolet light (power 72 W, time 80 seconds), a polyethyleneimine polymer hydrogel based on imine bonds and borate ester bonds (referred to as polymer hydrogel) was formed.

[0057] Effect Example 1

[0058] Weigh 0.5 g of the polymer hydrogel prepared in Example 1 and put it into a gel vial of known mass, and then put it into a conical flask containing VOC and seal it. After 2 hours, observe the changes in the gel (such as Figure 1 shown).

[0059] Results: The adsorption capacity of polymer hydrogel for acetone was 1.4 g / g (10 days), the adsorption capacity for methanol and ethanol was 2.0 g / g and 1.2 g / g respectively after 35 days, and the adsorption capacity for acetonitrile was 0.14 g / g (27 days). The color of the gel gradually darkened with the increase of adsorption time, the adsorption of acetone and acetonitrile produced phase separation, and the adsorption of methanol and ethanol increased the volume of the original gel.

[0060] Effect Example 2

[0061] Three portions of 0.5 g of the polymer hydrogel prepared in Example 1 were weighed and placed in four gel vials of known mass, which were then placed in conical flasks containing acetone, methanol, ethanol and acetonitrile and sealed. The total weight of the gel vials at different times was recorded, and the adsorption amount was calculated.

[0062] The results are as follows Figure 2 As shown, the adsorption capacity of the polymer hydrogel for acetone is 1.4 g / g (10 days), the adsorption capacity for methanol and ethanol after 35 days is 2.0 g / g and 1.2 g / g respectively, and the adsorption capacity for acetonitrile is 0.14 g / g (27 days).

[0063] Effect Example 3

[0064] Thirteen portions of 0.5 g of the polymer hydrogel prepared in Example 1 were weighed and placed in thirteen gel vials of known mass, which were then placed in conical flasks containing acetone, methanol, ethanol, acetonitrile, carbon tetrachloride, dichloromethane, cyclohexanol, ethyl acetate, benzene, toluene, chlorobenzene, aniline and n-hexane and sealed. Figure 3By observing the state of the gel vial, it was found that the polymer hydrogel could adsorb acetone, methanol, ethanol, and acetonitrile, but had no change in carbon tetrachloride, dichloromethane, cyclohexanol, ethyl acetate, benzene, toluene, chlorobenzene, aniline, and n-hexane.

[0065] Effect Example 4

[0066] Weigh 0.5 g of four portions of the polymer hydrogel prepared in Example 1 and put them into four gel vials of known mass, respectively, and then put them into conical flasks containing acetone, methanol, ethanol and acetonitrile and seal them, and record the status of the gel vials at different times. Figure 4 As shown, it can be observed that the color of the gel gradually darkens with the increase of adsorption time, the adsorption of acetone and acetonitrile produces phase separation, and the adsorption of methanol and ethanol increases the volume of the original gel.

[0067] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds, characterized in that: The following steps are involved: Dissolve polyethyleneimine and 4-acetophenylboronic acid in anhydrous ethanol to obtain S1 solution; The S1 solution was refluxed at 80° C. for 56 h and then freeze-dried to obtain the target product A; The target product A is dissolved in a sodium hydroxide solution to obtain a S2 solution; Dispersing hydrotalcite in dimethyl sulfoxide, and then adding tannic acid aqueous solution to obtain S3 solution; Add the monomer to the S3 solution and mix well, then add the aqueous solution of B, then add the S2 solution, initiator and lithium chloride, mix well and then irradiate with ultraviolet light to obtain the polyethyleneimine polymer hydrogel based on imine bonds and borate bonds; The substance B is one of polyvinyl alcohol, sodium alginate, guar gum, and hydroxypropyl guar gum; The monomer is one of sodium acrylate, acrylamide, acrylic acid, hydroxyethyl methacrylate, N-(2-hydroxyethyl)acrylamide, methacryloyloxyethyl trimethylammonium chloride, and 2-(dimethylamino)ethyl acrylate.

2. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The polyethyleneimine is linear polyethyleneimine or branched polyethyleneimine; the molecular weight of the polyethyleneimine is 10,000.

3. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The initiator is 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone.

4. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The mass volume ratio of the hydrotalcite, dimethyl sulfoxide, tannic acid, water, monomer, substance A, substance B, initiator and lithium chloride is 0.01g: 0.1mL: 0.005g: 0.6mL: (0.8-1.0)g: 0.005g: 0.01g: 0.01g.

5. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The concentration of the tannic acid aqueous solution is 5 wt %.

6. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The concentration of the aqueous solution of substance B is 1 wt %.

7. The method for preparing a polyethyleneimine polymer hydrogel based on imine bonds and borate bonds according to claim 1, characterized in that: The power of the ultraviolet irradiation is 72W, and the time is 80 seconds.

8. A polyethyleneimine polymer hydrogel based on imine bonds and borate bonds prepared according to the preparation method according to any one of claims 1 to 7.

9. Use of the polyethyleneimine polymer hydrogel based on imine bonds and borate bonds as claimed in claim 8 in the adsorption of VOCs.

Images