Preparation method and application of amphiphilic sulfur-rich polymer material

Abstract

The invention relates to a preparation method and application of an amphiphilic sulfur-rich polymer material, an amphiphilic sulfur-rich polymer is synthesized by taking elemental sulfur S8, a lipophilic monomer and a hydrophilic monomer as comonomers, and the preparation method comprises the following steps: S1, heating and mixing the elemental sulfur S8, the lipophilic monomer and the hydrophilic monomer to prepare a dispersed phase; s2, adding an emulsifier into a solvent, and heating to completely dissolve the emulsifier to prepare a continuous phase; and S3, adding the dispersed phase into the continuous phase, completely emulsifying the mixture, and reacting to generate a product. According to the invention, the preparation process of the sulfur-rich polymer is improved, and the reverse vulcanization reaction of elemental sulfur and multi-olefin is realized under the conditions of lower temperature and no catalyst by utilizing a free radical polymerization reaction mechanism. The elemental sulfur S8, the lipophilic monomer and the hydrophilic monomer are used as the comonomers, the raw materials are green and non-toxic, a toxic catalyst or high-temperature and high-pressure conditions possibly used in the traditional preparation process are avoided, the production cost is remarkably reduced, and the requirements of environmental protection and sustainable development are met.

Description

Technical Field

[0001] The invention belongs to the field of polymer adsorption materials, and in particular relates to a preparation method and application of an amphiphilic sulfur-rich polymer material. Background Art

[0002] With the rapid development of social economy, heavy metal pollution has become an increasingly prominent environmental problem. Among them, the discharge of heavy metal-containing wastewater is one of the main forms of heavy metal pollution. How to effectively control heavy metal pollution has become the focus and hot spot of attention.

[0003] Among the many heavy metal wastewater treatment methods, adsorption is considered to be one of the most attractive methods. In the adsorption method, the removal efficiency of heavy metal ions is closely related to the performance of the adsorbent. Although traditional adsorbents such as activated carbon, clay, zeolite and fly ash have been widely used to adsorb heavy metal ions, these adsorbents have small adsorption capacity, weak resistance to interference from coexisting ions, and poor selective adsorption capacity for heavy metal ions. Therefore, designing and synthesizing new adsorbents for efficient removal or recovery of low-concentration heavy metal ions in complex wastewater systems has become an important research topic in the field of adsorbent research.

[0004] High molecular polymers (such as modified natural polymers, high molecular sulfur polymers, geopolymers and conductive polymers, etc.) have broad application prospects due to their simple preparation, stable structure, and customizability, and they have high efficiency in adsorbing heavy metals. Among them, sulfur-containing polymers have the advantages of light weight, easy recovery after adsorbing heavy metal pollutants in water, stable products, and easy desorption, and are a new type of adsorption material with great potential.

[0005] Inverse vulcanization of polymers is the simplest and most practical method for preparing sulfur-containing polymers. Since Pyun et al. first reported the polymerization of S8 and 1,3-diisopropenylbenzene small molecule comonomers at 185°C to obtain high-sulfur polymers in 2013, scientists have developed a wider range of organic comonomers, including olefins, alkynes, natural olefins, allyl ethers, oleylamine, maleimide and benzoxazine. Sulfur-rich copolymers are becoming more and more popular as a new type of material that is expected to replace traditional copolymers. At present, the preparation of sulfur-rich polymers is mainly achieved by introducing cross-linking agents and catalysts. If there is no catalyst, the reaction needs to be carried out at high temperature, and the reaction monomers are relatively single. Therefore, how to achieve low-temperature inverse vulcanization reaction in the absence of catalysts and expand more polymerization monomers to make their application more extensive is an urgent problem to be faced and solved. Summary of the invention

[0006] In order to overcome the above-mentioned problems existing in the prior art, the purpose of the present invention is to provide a method for preparing an amphiphilic sulfur-rich polymer material and its application, utilizing the free radical polymerization reaction mechanism to synthesize an amphiphilic sulfur-rich polymer with elemental sulfur S8, a lipophilic monomer and a hydrophilic monomer as copolymer monomers at a relatively low temperature and in the absence of a catalyst.

[0007] The specific technical solutions provided by the present invention are as follows:

[0008] A method for preparing an amphiphilic sulfur-rich polymer material, using elemental sulfur S8, a lipophilic monomer and a hydrophilic monomer as copolymers to synthesize an amphiphilic sulfur-rich polymer, comprising the following steps:

[0009] S1, heating and mixing elemental sulfur S8, lipophilic monomer and hydrophilic monomer to prepare a dispersed phase;

[0010] S2, adding an emulsifier to the solvent, heating to completely dissolve the emulsifier, and obtaining a continuous phase;

[0011] S3. Add the dispersed phase into the continuous phase to completely emulsify the mixture and react to generate an amphiphilic sulfur-rich polymer.

[0012] Preferably, in step S1, the molar ratio of elemental sulfur S8, lipophilic monomer and hydrophilic monomer is (1-3):(1-3):(1-3), the heating temperature is 100-150°C, the elemental sulfur is melted, and stirred evenly to obtain a dispersed phase.

[0013] Preferably, the lipophilic monomer is one or more of aromatic hydrocarbons, aliphatic hydrocarbons and alkyl olefins.

[0014] Preferably, the aromatic hydrocarbons include styrene and substituted styrene, the aliphatic hydrocarbons include hexene and octene, and the alkyl olefins include tert-butyl olefin and isopentene.

[0015] Preferably, the hydrophilic monomer is one or more of olefin-containing anhydride substances and acrylamide substances.

[0016] Preferably, the olefin-containing anhydride substance includes one or more of maleic anhydride and itaconic anhydride, and the acrylamide substance is methacrylamide.

[0017] Preferably, in step S2, the ratio of the emulsifier to the solvent is (1-5) g: 200 mL, and the heating temperature is 100-150°C.

[0018] Preferably, the solvent is one or both of glycerol and polyethylene glycol, and the emulsifier is one or more of polyglycerol ricinoleate, glycerol monolaurate, fatty alcohol polyoxyethylene ether, polyethylene glycol 200, monolaurate, AbilEM90, nonylphenoxypolyethoxyethanol and OP series.

[0019] In the present invention, the boiling point of glycerol is much higher than the reaction temperature, and it is cheap and easy to obtain, so it is suitable as a reaction solvent in the reaction. However, elemental sulfur is insoluble in glycerol, and the solubility of styrene in glycerol is limited, so it is necessary to add an emulsifier to the reaction system to form a microemulsion, and hydrophilic maleic anhydride and lipophilic styrene and elemental sulfur are easily polymerized at the microemulsion interface to form a copolymer. The emulsifier mainly plays a role in improving the conversion rate of the reactants in the reaction.

[0020] Preferably, in step S3, the mixture is completely emulsified by ultrasound, the mixture is reacted at 100-150° C. for 3-5 hours, and after being cooled to room temperature, it is filtered to obtain an amphiphilic sulfur-rich polymer.

[0021] The present invention also provides an application of an amphiphilic sulfur-rich polymer material prepared by the preparation method of the amphiphilic sulfur-rich polymer material to adsorb heavy metals.

[0022] The preparation method and application of an amphiphilic sulfur-rich polymer material of the present invention have the following characteristics:

[0023] Beneficial effects:

[0024] (1) The present invention improves the preparation process of sulfur-rich polymers, and utilizes the free radical polymerization reaction mechanism to achieve the reverse vulcanization reaction of sulfur and polyolefins at a relatively low temperature and without a catalyst.

[0025] (2) The present invention uses elemental sulfur S8, lipophilic monomers and hydrophilic monomers as copolymers. The raw materials are widely available and are green and non-toxic. It avoids toxic catalysts or high temperature and high pressure conditions that may be used in traditional preparation processes, significantly reduces production costs, and meets the requirements of environmental protection and sustainable development.

[0026] (3) The amphiphilic sulfur-rich polymer material prepared by the present invention has both lipophilic and hydrophilic properties by introducing lipophilic monomers and hydrophilic monomers. This unique amphiphilic property enables the material to exhibit higher selectivity and efficiency in adsorbing heavy metal ions; it can effectively separate and enrich heavy metal ions in the solution. This property makes the material have broad application prospects in the fields of wastewater treatment, environmental protection, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a schematic diagram of the process for preparing the amphiphilic sulfur-rich polymer material. DETAILED DESCRIPTION

[0028] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation method, structure, characteristics and effects of the present invention are described in detail below in combination with the preferred embodiments.

[0029] Example 1

[0030] This embodiment provides a method for preparing an amphiphilic sulfur-rich polymer material, wherein elemental sulfur S8, a lipophilic monomer and a hydrophilic monomer are used as comonomers to synthesize an amphiphilic sulfur-rich polymer, such as Figure 1 As shown, it is a schematic diagram of the process of preparing amphiphilic sulfur-rich polymer materials according to the present invention.

[0031] Specifically, the preparation method comprises the following steps:

[0032] S1. Accurately weigh 1 mol of S8, 1 mol of styrene (St) and 1 mol of maleic anhydride (MA), mix them, heat them at 130°C, and stir them for about 30 minutes to melt the elemental sulfur and mix the reactants evenly to obtain a dispersed phase;

[0033] S2, adding 4 g of polyglycerol ricinoleate (PGPR) to 200 mL of glycerol, heating to 130° C. to completely dissolve it, and preparing a continuous phase;

[0034] S3, adding the dispersed phase to the continuous phase, mixing the two phases, and performing ultrasonic treatment for 10 minutes to completely emulsify the mixture, and then continuing the reaction at 130°C for 4 hours, cooling the reaction system naturally to room temperature, and then filtering to obtain an amphiphilic sulfur-rich polymer material. The reaction equation is as follows:

[0035]

[0036] Example 2

[0037] This embodiment provides a method for preparing an amphiphilic sulfur-rich polymer material, comprising the following steps:

[0038] S1. Accurately weigh 1 mol of S8, 1 mol of hexene and 1 mol of itaconic anhydride, mix them, heat at 130°C, and stir for about 30 minutes to melt the elemental sulfur and mix the reactants evenly to obtain a dispersed phase:

[0039] S2, adding 4 g of glyceryl monolaurate to 200 mL of glycerol, heating to 130° C. to completely dissolve it, to prepare a continuous phase;

[0040] S3. Add the dispersed phase to the continuous phase to mix the two phases, and perform ultrasonic treatment for 10 minutes to completely emulsify the mixture. Then, the mixture is reacted at 130° C. for 4 hours. The reaction system is naturally cooled to room temperature and filtered to obtain an amphiphilic sulfur-rich polymer material.

[0041] Example 3

[0042] This embodiment provides a method for preparing an amphiphilic sulfur-rich polymer material, comprising the following steps:

[0043] S1. Accurately weigh 1 mol of S8, 1 mol of tert-butyl olefin and 1 mol of methacrylamide, mix them, heat them at 130°C, and stir them for about 30 minutes to melt the elemental sulfur and mix the reactants evenly to obtain a dispersed phase;

[0044] S2, adding 4 g of fatty alcohol polyoxyethylene ether to 200 mL of polyethylene glycol, heating to 130° C. to completely dissolve it, to obtain a continuous phase;

[0045] S3. Add the dispersed phase to the continuous phase to mix the two phases, and perform ultrasonic treatment for 10 minutes to completely emulsify the mixture. Then, the mixture is reacted at 130° C. for 4 hours. The reaction system is naturally cooled to room temperature and filtered to obtain an amphiphilic sulfur-rich polymer material.

[0046] Application Example 1

[0047] The amphiphilic sulfur-rich polymer material prepared in Example 1 was subjected to an adsorption experiment. The experimental object was heavy metal ions in simulated wastewater. The experimental conditions were an initial metal ion concentration of 100 mg / L, an adsorbent dosage of 1.0 g / L, a temperature of 25°C, a pH of 6.0-7.0, and static adsorption for 24 hours. The adsorption experimental results are shown in Table 1.

[0048] Table 1 Heavy metal ion data in simulated wastewater

[0049]

[0050] Application Example 2

[0051] The amphiphilic sulfur-rich polymer material prepared in Example 1 was applied to remove heavy metal ions from actual electroplating industrial wastewater, where the concentration of heavy metal ions in the actual wastewater was 316 mg / L. The adsorption results are shown in Table 2.

[0052] Table 2 Data on adsorbent dosage and removal rate in actual wastewater

[0053]

[0054] Comparative Example 1

[0055] The difference between this comparative example and Example 1 is that the polymer is different.

[0056] The preparation method of the polymer in this comparative example is as follows: 1 mol of maleic anhydride monomer and 2 g of azobisisobutyl ester (initiator) are added to 500 mL of ethyl butyrate and ultrasonically dispersed to obtain reaction solution 1, nitrogen is introduced for 30 min, and the temperature is slowly raised to 80° C., 1 mol of styrene monomer and 12 mL of divinylbenzene (cross-linking agent) are dissolved in 500 mL of ethyl butyrate to obtain reaction solution 2, and then reaction solution 2 is dripped into reaction solution 1 at a speed of 5 d / s, reacted at 80° C. for 8 h, centrifuged, washed with ethanol, and dried at 35° C. for 24 h to obtain poly(styrene-maleic anhydride) nanospheres.

[0057] Application Example 3

[0058] The product prepared in Comparative Example 1 was subjected to the same adsorption test as in Application Example 1, and the results are shown in Table 3.

[0059] Table 3 Adsorption results of comparative examples

[0060]

[0061] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for preparing an amphiphilic sulfur-rich polymer material, characterized in that: The amphiphilic sulfur-rich polymer is synthesized by using elemental sulfur S8, a lipophilic monomer and a hydrophilic monomer as comonomers, comprising the following steps: S1, heating and mixing elemental sulfur S8, lipophilic monomer and hydrophilic monomer to prepare a dispersed phase; S2, adding an emulsifier to the solvent, heating to completely dissolve the emulsifier, and obtaining a continuous phase; S3. Add the dispersed phase into the continuous phase to completely emulsify the mixture and react to generate an amphiphilic sulfur-rich polymer.

2. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: In step S1, the molar ratio of elemental sulfur S8, lipophilic monomer and hydrophilic monomer is (1-3): (1-3): (1-3), the heating temperature is 100-150°C, the elemental sulfur is melted, and stirred evenly to obtain a dispersed phase.

3. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: The lipophilic monomer is one or more of aromatic hydrocarbons, aliphatic hydrocarbons and alkyl olefins.

4. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 3, characterized in that: Aromatic hydrocarbons include styrene and substituted styrenes, aliphatic hydrocarbons include hexene and octene, and alkyl olefins include tert-butyl olefin and isopentene.

5. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: The hydrophilic monomer is one or more of olefin-containing anhydride substances and acrylamide substances.

6. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 5, characterized in that: The olefin-containing anhydride substance includes one or both of maleic anhydride and itaconic anhydride, and the acrylamide substance is methacrylamide.

7. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: In step S2, the ratio of the emulsifier to the solvent is (1-5) g:200 mL, and the heating temperature is 100-150°C.

8. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: The solvent is one or both of glycerol and polyethylene glycol, and the emulsifier is one or more of polyglycerol ricinoleate, glycerol monolaurate, fatty alcohol polyoxyethylene ether, polyethylene glycol 200, monolaurate, AbilEM90, nonylphenoxypolyethoxyethanol and OP series.

9. The method for preparing an amphiphilic sulfur-rich polymer material according to claim 1, characterized in that: In step S3, the mixture is completely emulsified by ultrasound, and the mixture is reacted at 100-150° C. for 3-5 h. After cooling to room temperature, the mixture is filtered to obtain an amphiphilic sulfur-rich polymer.

10. Use of the amphiphilic sulfur-rich polymer material prepared by the preparation method according to any one of claims 1 to 9, characterized in that: Amphiphilic sulfur-rich polymer materials are used in heavy metal adsorption.

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