Preparation method and application of maleic rosin-based hydrogel

Abstract

This invention discloses a method for preparing maleic rosin-based hydrogels and their applications. The method includes: (1) synthesizing N-aminoethyl maleic rosin imide by reacting maleic rosin with ethylenediamine; (2) reacting N-aminoethyl maleic rosin imide with acryloyl chloride to synthesize N-(N′-acryloyl)aminoethyl maleic rosin imide; and (3) preparing the maleic rosin-based hydrogel by crosslinking and copolymerizing N-(N′-acryloyl)aminoethyl maleic rosin imide with dimethylaminopropylacrylamide. This method has simple reaction operation, mild reaction conditions, and low cost; the reaction has good specificity, and subsequent separation and purification are relatively simple; finally, the hydrogel product obtained by this method has good water absorption properties and can be used to remove toxic heavy metal cations from environmental water bodies, meeting the application needs of some special occasions, and possessing strong practical value and market prospects.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, specifically relating to a method for preparing maleic rosin-based hydrogels and their applications. Background Technology

[0002] Hydrogels are a class of polymers with a network structure that can swell in water, retain a large amount of water, and remain insoluble. Due to their excellent hydrophilicity and biocompatibility, hydrogels are widely used in agriculture, forestry and horticulture, industry, animal husbandry, food processing, medical materials, hygiene products, and textiles. Hydrogels are also a promising adsorbent material. Compared with traditional separation techniques such as membrane separation, chemical precipitation, and liquid-liquid extraction, hydrogel adsorbents offer high efficiency, ease of operation, low energy consumption, and no secondary pollution, making them widely used for the enrichment and separation of metal ions in industrial wastewater and environmental sewage. To improve wastewater reuse rates and reduce the harm caused by heavy metals, there is an urgent need to find a green, pollution-free, and highly efficient method for treating heavy metal wastewater. Adsorption, as a wastewater treatment process, has advantages such as simple operation, wide application, and long service life, and is considered the most practical wastewater treatment technology, widely used in multiple industrial sectors. However, the renewability and recovery rate of adsorbents remain challenges. Therefore, researchers have gradually begun to focus on the research of green, pollution-free, and low-cost new natural adsorbent materials, and hydrogel adsorbents are one of the research hotspots in this field.

[0003] Hydrogels can be classified into natural polymers and synthetic resins based on their raw material sources. Natural polymers are economical to obtain, possess excellent biocompatibility and biodegradability, and exhibit minimal toxicity. Therefore, natural polymers have become important raw materials for hydrogel preparation. This invention prepares a maleic rosin-based hydrogel, one of whose raw materials is a renewable, environmentally degradable, and biocycle-recyclable natural forest resource. Rosin itself has strong biochemical activity, and its hydrogen phenanthrene ring skeleton endows it with good structural rigidity and mechanical properties, making it widely used in many fields. Furthermore, rosin acid can undergo chemical reactions through the carboxyl group and conjugated double bond, two active groups, to target and prepare various rosin derivatives for different applications.

[0004] Maleic rosin is a product obtained by the addition reaction of rosin and maleic anhydride. Introducing maleic rosin into a hydrogel structure is expected to yield a series of maleic rosin-based hydrogel systems with good biocompatibility, degradability, and compliance with green chemistry requirements, thus greatly expanding the research scope of natural product hydrogels. Compared with other polymeric adsorbents such as chitosan, fibers, and resins, the hydrogel of this invention contains a large number of water molecules between its meshes, exhibiting a looser hydrophilic three-dimensional network structure. This results in higher mass transfer efficiency for adsorbates such as metal ions on the maleic rosin-based hydrogel adsorbent. This invention leverages my country's abundant rosin resources and unique chemical structure, promoting the development of rosin raw materials and products, exploring new avenues for the high-value utilization of rosin, and laying the foundation for the application of natural product rosin in new technological fields. Summary of the Invention

[0005] The technical objective of this invention is to address the shortcomings of existing technologies by providing a method for preparing maleic rosin-based hydrogels and their applications.

[0006] The technical objective of this invention is achieved as follows: a method for preparing maleic rosin-based hydrogels and their applications, characterized by comprising the following steps:

[0007] (1) Add male rosin to an appropriate amount of methanol, then add a certain amount of ethylenediamine, stir and react to obtain N-aminoethyl male rosin imide.

[0008] (2) At a certain temperature, an appropriate amount of acryloyl chloride was added dropwise into a dichloromethane solution of N-aminoethyl maleic rosin imide, the reaction was stirred for an appropriate time, and the mixture was separated and purified to obtain N-(N′-acryloyl)aminoethyl maleic rosin imide monomer.

[0009] (3) N-(N′-acryloyl)aminoethyl maleic rosin imide was added to an appropriate amount of toluene, followed by a certain amount of initiator, emulsifier, water, and dimethylaminopropylacrylamide. The reaction temperature was set, and the reaction was continued for a period of time. After the reaction was completed, the product was washed and dried to obtain maleic rosin-based hydrogel.

[0010] Preferably, in step (1), the molar ratio of maleic rosin to ethylenediamine is 1:1 to 3. The mass ratio of methanol to maleic rosin is 1:2.5 to 5.5.

[0011] Preferably, in step (2), the temperature at which acryloyl chloride is added is -5℃ to 15℃. The molar ratio of N-aminoethyl maleic rosin imide to acryloyl chloride is 1:2 to 6. The stirring time is 3 to 6 hours.

[0012] Preferably, in step (3), the mass ratio of N-(N′-acryloyl)aminoethyl maleic rosin imide to dimethylaminopropylacrylamide is 1:3.3 to 6.3. The volume ratio of toluene to water is 1:3 to 4. The initiator is azobisisobutyronitrile and potassium persulfate, and the amount of initiator is 1% to 10% of the total mass of N-(N′-acryloyl)aminoethyl maleic rosin imide and dimethylaminopropylacrylamide. The emulsifier is Tween 60 and Span 85. The reaction temperature is 60°C to 75°C, and the reaction time is 6 to 12 hours.

[0013] Preferably, the rosin in step (1) is derived from modified rosin, a renewable biomass resource.

[0014] By adopting the above solution, the present invention has the following advantages:

[0015] This invention uses Malaysian rosin as the starting material, with its precursor derived from modified rosin, a renewable biomass resource. Rosin is widely available and inexpensive, bringing economic benefits while reducing pollution, thus achieving comprehensive utilization of rosin and providing both economic and environmental benefits. The method is simple to operate, operates under mild conditions, and is low in cost. The reaction also exhibits good specificity, making subsequent separation and purification relatively simple. Finally, the hydrogel product obtained by this method has good water absorption properties and can be used to remove toxic heavy metal cations from environmental water bodies, meeting the application needs of some special occasions and possessing strong practical value and market prospects. Attached Figure Description

[0016] Figure 1 Schematic diagram of the chemical reaction principle of the maleic rosin-based hydrogel prepared by this invention

[0017] Figure 2 Infrared spectra of the maleic rosin-based hydrogel products prepared in this invention Detailed Implementation

[0018] The present invention is further illustrated by the following embodiments. Unless otherwise specified, all methods are conventional, and the experimental reagents and materials involved are conventional biochemical reagents and materials unless otherwise specified.

[0019] Example 1

[0020] (1) Add 10g of maleic rosin to 70ml of methanol, then add 1.5g of ethylenediamine, stir to react, and filter to obtain N-aminoethyl maleic rosin imide.

[0021] (2) 5.84 g of acryloyl chloride was added dropwise to a 10 g solution of N-aminoethyl maleic rosin imide in dichloromethane at 0 °C. The mixture was stirred for 3 hours. The mixture was extracted with saturated saline solution, and the organic phase was collected and rotary evaporated to obtain N-(N′-acryloyl)aminoethyl maleic rosin imide monomer.

[0022] (3) Take 2.5g of N-(N′-acryloyl)aminoethyl maleic rosin imide and add it to 30ml of toluene, 15.623g of dimethylaminopropylacrylamide, then add 200mg of azobisisobutyronitrile and 200mg of potassium persulfate, 0.8ml of Tween 60, 0.2ml of Span 85, and 100ml of pure water. Set the reaction temperature to 60℃ and stir mechanically for 8 hours. After the reaction is complete, wash the product with ethyl acetate and dry it to obtain maleic rosin-based hydrogel.

[0023] Example 2

[0024] (1) Add 10g of maleic rosin to 70ml of methanol, then add 3g of ethylenediamine, stir to react, and filter to obtain N-aminoethyl maleic rosin imide.

[0025] (2) 9.73 g of acryloyl chloride was added dropwise to a 10 g solution of N-aminoethyl maleic rosin imide in dichloromethane at 0 °C. The mixture was stirred for 5 hours. The mixture was extracted with saturated saline solution, and the organic phase was collected and rotary evaporated to obtain N-(N′-acryloyl)aminoethyl maleic rosin imide monomer.

[0026] (3) Take 1.5g of N-(N′-acryloyl)aminoethyl maleic rosin imide and add it to 30ml of toluene, 7.812g of dimethylaminopropylacrylamide, then add 200mg of azobisisobutyronitrile and 200mg of potassium persulfate, 0.8ml of Tween 60, 0.2ml of Span 85, and 100ml of pure water. Set the reaction temperature to 60℃ and stir mechanically for 8 hours. After the reaction is complete, wash the product with ethyl acetate and dry it to obtain maleic rosin-based hydrogel.

[0027] Example 3

[0028] (1) Add 10g of maleic rosin to 70ml of methanol, then add 4.5g of ethylenediamine, stir to react, and filter to obtain N-aminoethyl maleic rosin imide.

[0029] (2) 11.679 g of acryloyl chloride was added dropwise to a 10 g solution of N-aminoethyl maleic rosin imide in dichloromethane at 0 °C. The mixture was stirred for 6 hours. The mixture was extracted with saturated saline solution, and the organic phase was collected and rotary evaporated to obtain N-(N′-acryloyl)aminoethyl maleic rosin imide monomer.

[0030] (3) Take 5g of N-(N′-acryloyl)aminoethyl maleic rosin imide, add 30ml of toluene, 15.623g of dimethylaminopropylacrylamide, then add 200mg of azobisisobutyronitrile and 200mg of potassium persulfate, 0.8ml of Tween 60, 0.2ml of Span 85, and 100ml of pure water. Set the reaction temperature to 60℃ and stir mechanically for 12 hours. After the reaction is complete, wash the product with ethyl acetate and dry to obtain maleic rosin-based hydrogel.

[0031] Example 4

[0032] (1) Add 10g of maleic rosin to 70ml of methanol, then add 1.5g of ethylenediamine, stir to react, and filter to obtain N-aminoethyl maleic rosin imide.

[0033] (2) 11.679 g of acryloyl chloride was added dropwise to a 10 g solution of N-aminoethyl maleic rosin imide in dichloromethane at 0 °C. The mixture was stirred for 6 hours. The mixture was extracted with saturated saline solution, and the organic phase was collected and rotary evaporated to obtain N-(N′-acryloyl)aminoethyl maleic rosin imide monomer.

[0034] (3) Take 5g of N-(N′-acryloyl)aminoethyl maleic rosin imide, add 30ml of toluene, 15.623g of dimethylaminopropylacrylamide, then add 200mg of azobisisobutyronitrile and 200mg of potassium persulfate, 0.8ml of Tween 60, 0.2ml of Span 85, and 100ml of pure water. Set the reaction temperature to 60℃ and stir mechanically for 8 hours. After the reaction is complete, wash the product with ethyl acetate and dry to obtain maleic rosin-based hydrogel.

[0035] Example 5

[0036] This embodiment uses synthesized maleic rosin-based hydrogel as raw material to treat Cu. 2+ The specific process for simulated wastewater with an initial concentration of 50 mg / L is as follows:

[0037] Take 0.03 g of the prepared maleic rosin-based hydrogel and add it to 25 mL of a solution containing Cu. 2+ The wastewater was treated with shaking at room temperature for 24 hours. After treatment, the solution was filtered through a membrane and analyzed using atomic absorption spectrometry.

[0038] Experiments showed that maleic rosin-based hydrogels adsorb Cu 2+ The adsorption capacity was 29.348 mg / g.

[0039] Example 6

[0040] This embodiment uses synthesized maleic rosin-based hydrogel as raw material to treat Ni 2+ The specific process for simulated wastewater with an initial concentration of 50 mg / L is as follows:

[0041] Take 0.03 g of the prepared maleic rosin-based hydrogel and add it to 25 mL of a solution containing Ni. 2+ The wastewater was treated with shaking at room temperature for 24 hours. After treatment, the solution was filtered through a membrane and analyzed using atomic absorption spectrometry.

[0042] Experiments showed that the maleic rosin-based hydrogel adsorbed Ni 2+ The adsorption capacity was 21.828 mg / g.

[0043] Example 7

[0044] This embodiment uses synthesized maleic rosin-based hydrogel as raw material to treat Pb. 2+ The specific process for simulated wastewater with an initial concentration of 50 mg / L is as follows:

[0045] Take 0.03 g of the prepared maleic rosin-based hydrogel and add it to 25 mL of Pb-containing solution. 2+ The wastewater was treated with shaking at room temperature for 24 hours. After treatment, the solution was filtered through a membrane and analyzed using atomic absorption spectrometry.

[0046] Experiments showed that maleic rosin-based hydrogels adsorb Pb 2+ The adsorption capacity was 23.923 mg / g.

Claims

1. A method for preparing a maleic rosin-based hydrogel, characterized in that, It includes the following steps: (1) Add maleic rosin to methanol, then add ethylenediamine, stir and react to obtain N-aminoethyl maleic rosin imide; (2) Acryloyl chloride was added dropwise to a dichloromethane solution of N-aminoethyl maleic rosin imide, stirred, and purified to obtain N-(N ′ -Acryloyl)aminoethyl maleic rosin imide monomer; (3) N-(N′-acryloyl)aminoethyl maleic rosin imide was added to toluene, followed by an initiator, emulsifier, water and dimethylaminopropylacrylamide to react; after the reaction was completed, the product was washed and dried to obtain maleic rosin-based hydrogel. N-(N ′ The mass ratio of 1:3.3 to 6.3 is (-acryloyl)aminoethyl maleic rosin imide to dimethylaminopropylacrylamide.

2. The method for preparing a maleic rosin-based hydrogel according to claim 1, characterized in that, In step (1), the molar ratio of maleic rosin to ethylenediamine is 1:1 to 3; the mass ratio of methanol to maleic rosin is 1:2.5 to 5.

5.

3. The method for preparing a maleic rosin-based hydrogel according to claim 1, characterized in that, In step (2), the temperature at which acryloyl chloride is added is -5℃ to 15℃; the molar ratio of N-aminoethyl maleic rosin imide to acryloyl chloride is 1:2 to 6; and the stirring time is 3 to 6 hours.

4. The method for preparing a maleic rosin-based hydrogel according to claim 1, characterized in that, In step (3), the volume ratio of toluene to water is 1:3 to 4; the initiator is azobisisobutyronitrile and potassium persulfate, and the amount of initiator is 1% to 10% of the total mass of N-(N′-acryloyl)aminoethyl maleic rosin imide and dimethylaminopropylacrylamide; the emulsifier is Tween 60 and Span 85; the reaction temperature is 60℃ to 75℃, and the reaction time is 6 to 12 hours.

5. The method for preparing a maleic rosin-based hydrogel according to claim 1, characterized in that, The rosin described in step (1) is derived from the modification of rosin, a renewable biomass resource.

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