Photocatalytic composite catalyst and photocatalytic vinyl compound polymerization method
The photocatalytic initiator at room temperature is solved by photocatalytic composite catalyst, which requires high temperature reflux in traditional vinyl monomer polymerization reaction, and the vinyl compound polymerization in air is achieved, which is suitable for industrial production.
Patent Information
- Application Number
- CN202311828004.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-28
- Publication Date
- 2025-07-01
AI Technical Summary
The polymerization of traditional vinyl monomers requires high temperature reflux and strict water and oxygen removal conditions, which are harsh and not suitable for industrial production.
Using a photocatalytic composite catalyst, the photocatalytic initiator is generated under room temperature ultraviolet light irradiation, and the polymerization of vinyl compounds is initiated.
It avoids the harsh conditions of high temperature reflux. The reaction is feasible in the air without water removal and oxygen removal. The conditions are mild, there are few side reactions, high product yields, easy to adjust molecular weight, and suitable for industrial-scale production.
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of organic compound synthesis, and specifically relates to a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds. Background Art
[0002] Polyvinyl materials are very important polymer compounds in functional polymer materials and are commonly used raw materials in industrial production. They can be used as conductive materials, membrane materials, luminescent materials, antistatic coatings, and battery materials.
[0003] Currently, for the polymerization reaction of vinyl monomers, the traditional method is to carry out the polymerization reaction of vinyl monomers under heating reflux and the action of initiators. Such reaction conditions are harsh, requiring heating reflux and strict control of the water content and oxygen content. There is an urgent need to conduct research on the polymerization reaction of vinyl monomers to solve the problems of the existing technology. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for photocatalytic polymerization of a photocatalytic composite catalyst and a vinyl compound, which avoids the harsh conditions of high-temperature reflux required by traditional polymerization reactions. This reaction can be carried out in air without the need for water and oxygen removal.
[0005] To achieve the purpose of this invention, the following technical solutions are adopted:
[0006] The first purpose of the present invention is to provide a photocatalytic composite catalyst, which includes a solid-phase nanomaterial and a photosensitizer loaded on the surface of the solid-phase nanomaterial.
[0007] Specifically, the solid-phase nanomaterial is selected from one of Fe2O3, WO3, ZnO, SiO2, or diatomite.
[0008] Specifically, the photosensitizer is selected from one of pheophorbide A, chlorophyllin, phycobilin, curcumin, resveratrol, and cercosporin.
[0009] Specifically, the feeding mass ratio of the solid-phase nanomaterial to the photosensitizer is 10:(1 - 2); preferably, the feeding mass ratio of the solid-phase nanomaterial to the photosensitizer can be 10:1, 10:1.1, 10:1.2, 10:1.3, 10:1.4, 10:1.5, 10:1.6, 10:1.7, 10:1.8, 10:1.9, or 10:2, etc., but not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0010] The second purpose of the present invention is to provide a method for photocatalytic polymerization of vinyl compounds. Under light irradiation conditions, the above photocatalytic composite catalyst photocatalyzes an initiator to initiate the polymerization of vinyl compounds to obtain a polymer.
[0011] Specifically, the initiator is one selected from triethylborane, photoinitiator TPO, photoinitiator 2959, and photoinitiator 1173;
[0012] Preferably, the polymerization reaction further includes a solvent, and the solvent is one selected from water, methanol, dimethylformamide, and dimethyl sulfoxide.
[0013] Specifically, the vinyl compound is one selected from N-vinylpyrrolidone, styrene, sodium styrene sulfonate, N-vinylcaprolactam, N-vinylformamide, ethyl vinyl ether, and ethylene glycol divinyl ether.
[0014] Specifically, the mass ratio of the vinyl compound to the composite catalyst in the feed is 10:(1-2); preferably, the mass ratio of the vinyl compound to the composite catalyst in the feed can be 10:1, 10:1.1, 10:1.2, 10:1.3, 10:1.4, 10:1.5, 10:1.6, 10:1.7, 10:1.8, 10:1.9, or 10:2, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0015] Preferably, the molar concentration of the vinyl compound is 1-10 mol / L; more preferably, the molar concentration of the vinyl compound can be 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, or 10 mol / L, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0016] Specifically, the molar ratio of the vinyl compound to the initiator in the feed is 1:(0.001-0.05); preferably, the molar ratio of the vinyl compound to the initiator in the feed can be 1:0.001, 1:0.002, 1:0.003, 1:0.004, 1:0.005, 1:0.006, 1:0.007, 1:0.008, 1:0.009, 1:0.01, 1:0.015, 1:0.02, 1:0.025, 1:0.03, 1:0.035, 1:0.04, 1:0.045, or 1:0.05, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] The present invention provides a method for preparing a photocatalytic composite catalyst and photocatalytic polymerization of vinyl compounds. A photosensitizer is loaded on the surface of a solid-phase nanomaterial to form a photocatalytic composite catalyst. Under the irradiation of room-temperature ultraviolet light, the photocatalytic composite catalyst photocatalyzes an initiator to generate free radicals, which initiate the polymerization of vinyl compounds. This avoids the harsh conditions of high-temperature reflux required in traditional polymerization reactions. This reaction can be carried out in air without the need for water and oxygen removal; the reaction conditions are mild, side reactions are few, the product yield is high, and the molecular weight of the product is easily adjustable, which is conducive to industrial scale production. Specific Embodiments
[0019] The technical solution of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.
[0020] Any method in the prior art can be used to prepare the photosensitizer material supported on the solid-phase nanomaterial. One of the methods we prepared is listed here.
[0021] Example 1
[0022] This example provides a method for preparing a photocatalytic composite catalyst and photocatalytic polymerization of vinyl compounds, including the following steps:
[0023] 1. The photocatalytic composite catalyst is cercosporin@SiO2, and its preparation method is as follows: Add 50 g of mesoporous silica nanospheres to 100 ml of water, then add 7.5 g of cercosporin, stir at room temperature overnight, filter, wash, and dry to obtain 56.5 g of cercosporin@SiO2 nanospheres for standby;
[0024] 2. Add 20 g of sodium styrene sulfonate, 75 ml of water, 2 g of cercosporin@SiO2 nanospheres, and 0.05 g of initiator triethylborane to the reaction flask, and react overnight under room-temperature ultraviolet light irradiation. After the reaction is completed, filter and recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrene sulfonic acid solution with a molecular weight of about 30,000 was obtained.
[0025] Example 2
[0026] This example provides a method for preparing a photocatalytic composite catalyst and photocatalytic polymerization of vinyl compounds, including the following steps. The cercosporin@SiO2 nanospheres prepared in Example 1 are used for the preparation of step 2, as follows:
[0027] Add 20 g of sodium styrene sulfonate, 75 ml of water, 2 g of cercosporin@SiO2 nanospheres and 0.025 g of initiator triethylborane into a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrene sulfonic acid solution with a molecular weight of about 60,000 was obtained.
[0028] Example 3
[0029] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps. The cercosporin@SiO2 nanospheres prepared in Example 1 are selected for the preparation in Step 2 as follows:
[0030] Add 20 g of sodium styrene sulfonate, 75 ml of water, 2 g of cercosporin@SiO2 nanospheres and 0.1 g of initiator triethylborane into a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrene sulfonic acid solution with a molecular weight of about 15,000 was obtained.
[0031] Example 4
[0032] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps. The cercosporin@SiO2 nanospheres prepared in Example 1 are selected for the preparation in Step 2 as follows:
[0033] Add 20 g of sodium styrene sulfonate, 10 ml of water, 2 g of cercosporin@SiO2 nanospheres and 0.05 g of initiator triethylborane into a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrene sulfonic acid solution with a molecular weight of about 50,000 was obtained.
[0034] Example 5
[0035] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps. The cercosporin@SiO2 nanospheres prepared in Example 1 are selected for the preparation in Step 2 as follows:
[0036] Add 20 g of sodium styrenesulfonate, 75 ml of water, 1 g of cercosporin@SiO₂ nanospheres, and 0.025 g of initiator triethylborane to a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrenesulfonic acid solution with a molecular weight of about 55,000 was obtained.
[0037] Example 6
[0038] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps. The cercosporin@SiO₂ nanospheres prepared in Example 1 are selected for the preparation in Step 2 as follows:
[0039] Add 20 g of sodium styrenesulfonate, 75 ml of water, 1.5 g of cercosporin@SiO₂ nanospheres, and 0.025 g of initiator triethylborane to a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrenesulfonic acid solution with a molecular weight of about 70,000 was obtained.
[0040] Example 7
[0041] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps:
[0042] 1. The photocatalytic composite catalyst is chlorophyllin@ZnO, and its preparation method is as follows: Add 50 g of zinc oxide nanospheres to 100 ml of water, then add 10.1 g of chlorophyllin, stir overnight at room temperature, filter, wash, and dry to obtain 54 g of chlorophyllin@ZnO nanospheres for standby;
[0043] 2. Add 14 g of N-vinylcaprolactam, 75 ml of methanol, 1.4 g of chlorophyllin@ZnO nanospheres, and 0.35 g of initiator TPO to a reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter to recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a poly-N-vinylcaprolactam solution with a molecular weight of about 14,000 was obtained.
[0044] Example 8
[0045] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps:
[0046] 1. The photocatalytic composite catalyst is phycobilin@Fe2O3, and its preparation method is as follows: Add 50 g of Fe2O3 nanospheres to 100 ml of water, then add 8.2 g of phycobilin, stir overnight at room temperature, filter, wash, and dry to obtain 56 g of phycobilin@Fe2O3 nanospheres for standby;
[0047] 2. Add 7.2 g of ethyl vinyl ether, 75 ml of dimethylformamide, 0.72 g of phycobilin@Fe2O3 nanospheres, and 0.22 g of photoinitiator 2959 to the reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter and recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polyethyl vinyl ether solution with a molecular weight of about 7500 is obtained.
[0048] Example 9
[0049] This example provides a photocatalytic composite catalyst and a method for photocatalytic polymerization of vinyl compounds, including the following steps:
[0050] 1. The photocatalytic composite catalyst is resveratrol@diatomite, and its preparation method is as follows: Add 50 g of diatomite nanospheres to 100 ml of water, then add 3.2 g of resveratrol, stir overnight at room temperature, filter, wash, and dry to obtain 52 g of resveratrol@diatomite nanospheres for standby;
[0051] 2. Add 13.2 g of ethylene glycol divinyl ether, 75 ml of dimethyl sulfoxide, 1 g of resveratrol@diatomite nanospheres, and 0.16 g of photoinitiator 1173 to the reaction flask, and react overnight under ultraviolet light irradiation at room temperature. After the reaction is completed, filter and recover the catalyst, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polyethylene glycol divinyl ether solution with a molecular weight of about 12000 is obtained.
[0052] Comparative Example 1
[0053] This comparative example provides a method for polymerizing vinyl compounds. Add 20 g of sodium styrene sulfonate and 75 ml of water (purged with nitrogen for half an hour) to the reaction flask, and under the condition of nitrogen protection, add 0.11 g of sodium persulfate and react overnight at 90°C. After the reaction is completed, cool to room temperature, pass the filtrate through the prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, a polystyrene sulfonic acid solution with a molecular weight of about 30000 is obtained.
[0054] Comparative Example 2
[0055] This comparative example provides a method for polymerizing vinyl compounds. 14 g of N-vinylcaprolactam and 75 ml of water (purged with nitrogen for half an hour) were added to a reaction flask. Under nitrogen protection, 0.041 g of azobisisobutyronitrile was added, and the reaction was heated at 90 °C overnight. After the reaction was completed, it was cooled to room temperature, and the filtrate was passed through a prepared cation exchange resin to exchange sodium ions into hydrogen ions. By GPC detection, an N-vinylcaprolactam solution with a molecular weight of about 55,000 was obtained.
[0056] Comparing the examples and comparative examples, the preparation method of the present invention avoids the harsh conditions of high-temperature reflux required in traditional polymerization reactions. This reaction can be carried out in air without the need for water and oxygen removal.
[0057] From the comparison of Examples 1-3, it can be seen that changing the amount of initiator will change the number of active centers in the polymerization reaction. The more initiator, the more active centers are generated, the shorter the polymer chain segments formed, and the smaller the molecular weight. Conversely, the molecular weight is larger.
[0058] From the comparison of Examples 1 and 4, it can be seen that changing the concentration of the polymerization monomer will change the polymerization reaction rate, change the collision frequency between the monomer and the active chain segment, and thus change the molecular weight.
[0059] From the comparison of Examples 1, 5-6, it can be seen that changing the feeding molar ratio of the composite catalyst to the vinyl compound will change the polymerization reaction rate, change the collision frequency between the monomer and the active chain segment, and thus change the molecular weight of the polymer.
[0060] From the comparison of Examples 1, 7-9, it can be seen that changing the type of the photocatalytic composite catalyst does not affect the molecular weight of the polymers polymerized by different monomers, solvents, and initiators.
[0061] In summary, the present invention provides a method for photocatalytic polymerization of a photocatalytic composite catalyst and a vinyl compound. The photosensitizer is loaded on the surface of the solid-phase nanomaterial to form a photocatalytic composite catalyst; under the irradiation of room-temperature ultraviolet light, the photocatalytic composite catalyst photocatalyzes triethylborane to generate ethyl radicals, which initiate the polymerization of vinyl compounds. It avoids the harsh conditions of high-temperature reflux required in traditional polymerization reactions. This reaction can be carried out in air without the need for water and oxygen removal; the reaction conditions are mild, the side reactions are few, the product yield is high, the product molecular weight is easy to adjust, and it is conducive to industrial scale production.
[0062] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.
Claims
1. A photocatalytic composite catalyst, characterized in that, It includes solid-phase nanomaterials and photosensitizers loaded on the surface of the solid-phase nanomaterials.
2. The photocatalytic composite catalyst according to claim 1, wherein The solid-phase nanomaterials are selected from one of Fe2O3, WO3, ZnO, SiO2 or diatomite.
3. The photocatalytic composite catalyst according to claim 1, wherein The photosensitizer is selected from one of pheophorbide A, chlorophyllin, phycobilin, curcumin, resveratrol and cercosporin.
4. The photocatalytic composite catalyst according to claim 1, wherein, The mass ratio of the solid-phase nanomaterials to the photosensitizer in the feed is 10:(1-2).
5. A method for photocatalytic polymerization of vinyl compounds, characterized in that, Under light irradiation conditions, the photocatalytic initiator is used with the photocatalytic composite catalyst according to any one of claims 1-4 to initiate the polymerization of vinyl compounds to obtain a polymer.
6. The method according to claim 5, wherein The initiator is selected from one of triethylborane, photoinitiator TPO, photoinitiator 2959, photoinitiator 1173; Preferably, the polymerization reaction further includes a solvent, and the solvent is selected from one of water, methanol, dimethylformamide, dimethyl sulfoxide.
7. The method according to claim 5, characterized in that, The vinyl compound is selected from one of N-vinylpyrrolidone, styrene, sodium styrene sulfonate, N-vinylcaprolactam, N-vinylformamide, ethyl vinyl ether, ethylene glycol divinyl ether.
8. The method according to any one of claims 5 to 7, characterized in that The mass ratio of the vinyl compound to the composite catalyst in the feed is 10:(1-2).
9. The method according to any one of claims 5 to 7, characterized in that, The molar concentration of the vinyl compound is 1-10 mol / L.
10. The method according to any one of claims 5-7, characterized in that The molar ratio of the vinyl compound to the initiator in the feed is 1:(0.001-0.05).