Near-infrared two-zone photothermal hyperbranched conjugated polymer and its sealant antifungal application

Abstract

This invention discloses a near-infrared II photothermal hyperbranched conjugated polymer and its antifungal application in sealants. Using 4,7-bis(2-bromo-5-thiophene)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) as the electron acceptor unit, 2,6-di(trimethyltin)-4H-cyclopentano[2,1-B:3,4-B']dithiophene as the electron donor unit, and tri(4-bromophenyl)amine as the branching unit, a neutral hyperbranched conjugated polymer is obtained through coupling polymerization. This neutral hyperbranched conjugated polymer undergoes a quaternization reaction with dimethylamine, followed by functionalization modification with 3-bromomethylphenylboronic acid to prepare a cationic phenylboronic acid-functionalized hyperbranched conjugated polymer. This polymer exhibits broad and strong absorption and highly efficient photothermal conversion capabilities in the near-infrared II region.

Description

Technical Field

[0001] This invention belongs to the field of sealant application technology, and relates to a near-infrared II photothermal hyperbranched conjugated polymer and its anti-mildew sealant application. Specifically, it relates to a hyperbranched conjugated polymer with near-infrared II absorption and photothermal effect, a photo-irradiated antibacterial sealant, its preparation method and application. Background Technology

[0002] Silicone materials are mostly paste-like, allowing for easy control of thickness and application shape. Compared to the aforementioned materials, they offer advantages such as a wider range of acid and alkali resistance, superior resistance to UV aging, outstanding adhesion, and good waterproofing. Silicone sealants are widely used in construction, coating, and other daily life applications, including polymer cement. In daily life, damp environments easily lead to bacterial and mold growth on coated surfaces. Existing antibacterial methods include adding antibacterial agents and antifungal materials such as nano-silicone to silicone sealants. However, these methods suffer from drawbacks such as limited antifungal effect, high cost, and short-lived antifungal effect. Therefore, it is necessary to develop antifungal silicone sealants using novel antibacterial agents to address these issues.

[0003] Photothermal therapy utilizes materials with high photothermal conversion efficiency. These materials are cultured with bacteria, and then, under the irradiation of an external light source (white light and near-infrared light), the light energy is converted into heat energy to kill the bacteria. Similarly, cationic molecules have a certain inhibitory effect on the reproduction of bacteria and other microorganisms. Summary of the Invention

[0004] Objective: To address the problem of mold growth in silicone sealants, this invention utilizes the photothermal effect in the second region to provide a novel method for effective antibacterial and anti-mold treatment. It develops a near-infrared second-region photothermal hyperbranched conjugated polymer and an antibacterial and anti-mold silicone sealant prepared using this hyperbranched conjugated polymer. This invention aims to improve the antibacterial effect of silicone sealants in their application environment, enhance the timeliness of antibacterial and anti-mold treatment, and achieve high-quality, light-controlled antibacterial and anti-mold effects.

[0005] The technical solution adopted in this invention is as follows:

[0006] In a first aspect, a hyperbranched conjugated polymer with near-infrared II absorption and photothermal effect is provided, wherein the hyperbranched conjugated polymer is a phenylboronic acid-functionalized cationic hyperbranched conjugated polymer with the following chemical structural formula:

[0007] ,

[0008] Where n represents the number of repeating units, and n is 3 to 9.

[0009] Furthermore, the hyperbranched conjugated polymer hyperbranched framework is constructed by electron acceptor units, electron donor units, and branching units via Stille coupling reaction. The electron acceptor unit is 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole), the electron donor unit is 2,6-bis(trimethyltin)-4H-cyclopentano[2,1-B:3,4-B']dithiophene, and the branching unit is tris(4-bromophenyl)amine.

[0010] Secondly, a method for preparing the hyperbranched conjugated polymer is provided, comprising:

[0011] S1: A coupling polymerization reaction was carried out using 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) as an electron acceptor unit, 2,6-di(trimethyltin)-4H-cyclopentano[2,1-B:3,4-B']dithiophene as an electron donor unit, and tris(4-bromophenyl)amine as a branching unit to obtain a neutral hyperbranched conjugated polymer; the structural formula of the neutral hyperbranched conjugated polymer is as follows:

[0012] ;

[0013] S2: The neutral hyperbranched conjugated polymer obtained in step S1 is subjected to a quaternization reaction with dimethylamine, and then reacted with 3-bromomethylphenylboronic acid to obtain the final product.

[0014] In this embodiment, the synthetic route for the hyperbranched conjugated polymer is as follows:

[0015]

[0016] In some embodiments, in step S1, the molar ratio of 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole), 2,6-bis(trimethyltin)-4H-cyclopenta[2,1-B:3,4-B']dithiophene to tris(4-bromophenyl)amine is 1:1:0.2;

[0017] In some embodiments, in step S2, the molar ratio of the neutral hyperbranched conjugated polymer, dimethylamine, and 3-bromomethylphenylboronic acid is 1:180:180.

[0018] In step S1, anhydrous toluene is used as the reaction solvent;

[0019] In step S1, the reaction conditions are 2-6 hours in an oxygen-free environment at 110°C;

[0020] In step S1, dipalladium (dibenzylacetone) and tris(o-methylphenyl)phosphine are added as catalysts during the reaction.

[0021] In step S2, the quaternization reaction conditions are: reaction in an ice bath for 1 hour, followed by reaction in an oil bath at 50°C for 3 days;

[0022] In step S2, the reaction with 3-bromomethylphenylboronic acid is carried out under anhydrous and oxygen-free conditions for 3 days.

[0023] Thirdly, the application of the hyperbranched conjugated polymer in the antibacterial and antifungal properties of sealants is provided.

[0024] Fourthly, a silicone sealant comprising the aforementioned hyperbranched conjugated polymer doped with is provided.

[0025] In some embodiments, the method for preparing the silicone sealant includes:

[0026] Step 1: The toluene solution of the hyperbranched conjugated polymer in the near-infrared II region is rapidly added to water under ultrasonic conditions and dispersed. Then the dispersion is mixed with the base glue to obtain the masterbatch.

[0027] Step 2: Mix the obtained masterbatch with the base adhesive, crosslinking agent, filler, catalyst, plasticizer and coupling agent to obtain silicone sealant.

[0028] In some embodiments, the base adhesive is α,ω-dihydroxypolydimethylsiloxane, the crosslinking agent is methyltributanone oxime silane, the filler is calcium carbonate, the catalyst is dibutyltin dilaurate, the plasticizer is polydimethylsiloxane, and the coupling agent is γ-aminopropyltriethoxysilane.

[0029] In some embodiments, the mixing is carried out in a mixer at room temperature;

[0030] In some embodiments, in step 1, the mass ratio of the hyperbranched conjugated polymer to the base adhesive is 1:5 to 1:100;

[0031] In some embodiments, in step 2, the mass ratio of the masterbatch to the base adhesive, crosslinking agent, filler, catalyst, plasticizer, and coupling agent is 0.1:70:5:10:0.1:10:2.

[0032] Fifthly, the application of the aforementioned silicone sealant in antibacterial and antifungal applications is provided.

[0033] The beneficial effects of this invention include: This invention designs, synthesizes, and prepares a hyperbranched conjugated polymer with near-infrared II absorption and photothermal effects. This hyperbranched conjugated polymer is obtained through a coupling reaction using 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) as an electron acceptor unit, 2,6-di(trimethyltin)-4H-cyclopentano[2,1-B:3,4-B']dithiophene as an electron donor unit, and tris(4-bromophenyl)amine as a branching unit. The resulting neutral hyperbranched conjugated polymer is then obtained through quaternization and phenylboronic acid modification. The synthetic route and preparation method are simple and efficient. The obtained hyperbranched conjugated polymer exhibits broad and strong absorption in the near-infrared II region and excellent photothermal conversion efficiency. It can effectively solve the problem of mold growth in sealants under humid environments. When this polymer is mixed with silicone sealant, it generates a localized photothermal effect under near-infrared II laser irradiation, achieving efficient, controllable, and long-lasting antibacterial and antifungal effects, and has good application prospects. Attached Figure Description

[0034] Figure 1 The NMR spectrum of the hyperbranched conjugated polymer with near-infrared II absorption and photothermal effect obtained in Example 1 of this invention;

[0035] Figure 2 The absorption spectrum of the hyperbranched conjugated polymer with near-infrared II absorption and photothermal effect obtained in Example 1 of the present invention is shown.

[0036] Figure 3 The 1064 nm laser photothermal heating curve of the near-infrared II fluorescent conjugated polymer with near-infrared II absorption and photothermal effect obtained in Example 1 of this invention;

[0037] Figure 4 This is an image of the temperature rise caused by 1064 nm laser irradiation of the hyperbranched conjugated polymer with near-infrared II absorption and photothermal effect obtained in Example 1 of the present invention.

[0038] Figure 5 These are photographs of the reactants and the resulting near-infrared II photothermal hyperbranched conjugated polymer-doped silicone sealant from Example 2 of this invention (left: hyperbranched conjugated polymer; right: silicone sealant).

[0039] Figure 6 This is a temperature rise imaging image of the near-infrared II region photothermal hyperbranched conjugated polymer-doped silicone sealant obtained in Example 2 of the present invention.

[0040] Figure 7 This is a photograph of the antibacterial effect of the silicone sealant doped with near-infrared II absorption and photothermal hyperbranched conjugated polymer obtained in Example 2 of the present invention. Detailed Implementation

[0041] To further illustrate the present invention, a series of embodiments are given below. These embodiments are purely illustrative and are only used to specifically describe the present invention. They should not be construed as limiting the present invention.

[0042] In this embodiment of the application, the synthetic route of the hyperbranched conjugated polymer is as follows:

[0043]

[0044] Example 1: A method for synthesizing a hyperbranched conjugated polymer, comprising:

[0045] The electron acceptor unit 4,8-bis(5-bromo-2-thienyl)-benzo[1,2-c:4,5-c']bis[1,2,5]thiadiazole (1.0 mmol, 516 mg), the electron donor unit (4,4-bis(6-bromohexyl)-4H-cyclopentadien[2,1-b:3,4-b']dithiophene-2,6-diyl)bis(trimethylstanane) (1.0 mmol, 830 mg), and the branching unit tri(4-bromophenyl)amine (0.2 mmol, 96.4 mg) were added to a polymerization tube in a molar ratio of 1:1:0.2. Then, the catalyst (tribenzylacetone) dipalladium (0.0064 mmol, 2.0 mg), the ligand triphenylphosphine (0.00436 mmol, 4.0 mg), and anhydrous toluene (2.5 mL) were added. The reaction was carried out in an anaerobic environment in an oil bath at 110°C. The reaction ended when the solution changed from dark green to black. After cooling, the reaction solution was poured into a large amount of methanol to settle. The black solid was collected by filtration and dried to obtain a neutral hyperbranched conjugated polymer.

[0046] 100 mg of neutral hyperbranched conjugated polymer was dissolved in 10 mL of anhydrous tetrahydrofuran. 3 mL of 33 wt% dimethylamine solution was slowly added under ice bath conditions. The reaction was first carried out in an ice bath for 1 hour, then transferred to an oil bath at 50 °C and reacted for 3 days. The solvent was removed by rotary evaporation. Subsequently, 10 mL of anhydrous tetrahydrofuran and 20 mg of 3-bromomethylphenylboronic acid were added, and the reaction was carried out under anaerobic and anhydrous conditions for 3 days. Finally, phenylboronic acid-functionalized cationic hyperbranched conjugated polymer was precipitated in the solvent. The NMR spectrum of the prepared hyperbranched conjugated polymer is shown below. Figure 1 As shown.

[0047] like Figure 2 and Figure 3 As shown, the absorption and photothermal heating curves of the prepared hyperbranched conjugated polymer are presented. Figure 2 It can be seen that its UV-Vis-NIR absorption peaks in tetrahydrofuran cover the range of 700 nm to 1300 nm. Under 1064 nm laser irradiation, the hyperbranched conjugated polymer solution can be rapidly heated to above 70 °C. Figure 3It exhibits significantly superior near-infrared II absorption and photothermal properties. From Figure 4 It can be seen that the temperature increases with the extension of laser irradiation time, which demonstrates its excellent photothermal performance.

[0048] A 3.0 mg / mL deuterated chloroform solution of the hyperbranched conjugated polymer was prepared, and its 1H NMR spectrum was measured. Figure 1 As shown.

[0049] A tetrahydrofuran solution with a hyperbranched conjugated polymer concentration of 0.02 mg / mL was prepared and tested using a UV-Vis-NIR spectrometer. Figure 2 As shown, the absorption peak covers the range of 700-1300 nm, with strong absorption still present at 1064 nm.

[0050] A tetrahydrofuran solution with a hyperbranched conjugated polymer concentration of 0.02 mg / mL was prepared, and its photothermal heating curve was tested, as shown below. Figure 3 As shown, the temperature can rise to over 70°C under 1064 nm laser irradiation.

[0051] A tetrahydrofuran solution with a hyperbranched conjugated polymer concentration of 0.02 mg / mL was prepared and gradually irradiated with a 1064 nm laser. The solution temperature gradually increased, indicating that the hyperbranched conjugated polymer has excellent photothermal effect.

[0052] Example 2: A method for preparing a hyperbranched conjugated polymer-doped silicone sealant, comprising:

[0053] 100 mg of hyperbranched conjugated polymer was dissolved in 20 mL of tetrahydrofuran. Under strong sonication, the dissolved tetrahydrofuran solution of the hyperbranched conjugated polymer was directly added to 20 mL of water. Excess tetrahydrofuran was then removed using a vacuum method to obtain a dispersion of phenylboronic acid-functionalized cationic hyperbranched conjugated polymer. The dispersion was further added to 1000 mg of the base adhesive α,ω-dihydroxypolydimethylsiloxane to obtain a green masterbatch.

[0054] In a mixer, the obtained 1 gram of masterbatch is mixed with 700 grams of base adhesive α,ω-dihydroxypolydimethylsiloxane, 50 grams of crosslinking agent methyl tributanone oxime silane, 100 grams of filler calcium carbonate, 1 gram of catalyst dibutyltin dilaurate, 100 grams of plasticizer polydimethylsiloxane, and 20 grams of coupling agent γ-aminopropyltriethoxysilane to obtain the final product.

[0055] Example 3: A method for preparing a hyperbranched conjugated polymer-doped silicone sealant, comprising:

[0056] 900 mg of hyperbranched conjugated polymer was dissolved in 20 mL of tetrahydrofuran. Under strong sonication, the dissolved tetrahydrofuran solution of hyperbranched conjugated polymer was directly added to 20 mL of water. Excess tetrahydrofuran was then removed using a vacuum method to obtain a dispersion of the hyperbranched conjugated polymer. The dispersion was further added to 90,000 mg of the base adhesive α,ω-dihydroxypolydimethylsiloxane, and excess tetrahydrofuran was removed again using a vacuum method to obtain a yellow-green masterbatch.

[0057] In a mixer, the obtained 10g of masterbatch is mixed with 7000g of base adhesive α,ω-dihydroxypolydimethylsiloxane, 500g of crosslinking agent methyl tributanone oxime silane, 1000g of filler calcium carbonate, 10g of catalyst dibutyltin dilaurate, 1000g of plasticizer polydimethylsiloxane, and 200g of coupling agent γ-aminopropyltriethoxysilane to obtain the final product.

[0058] Photographs of the hyperbranched conjugated polymer-doped silicone sealant prepared in Example 2 are shown. Figure 5 As shown;

[0059] The hyperbranched conjugated polymer-doped silicone sealant prepared in Example 2 was coated onto a glass slide, and its photothermal heating performance was tested. Figure 6 As shown, the temperature can be raised to over 70°C under irradiation by a 1064 nm laser.

[0060] The hyperbranched conjugated polymer-doped silicone sealant prepared in Example 2 ( Figure 7 (Left side) and sealant that does not contain hyperbranched conjugated polymers ( Figure 7 (Right side) After 30 days of mold treatment, such as Figure 7 As shown, the hyperbranched conjugated polymer of the present invention has a good anti-mildew effect.

[0061] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hyperbranched conjugated polymer exhibiting near-infrared II absorption and photothermal effect, characterized in that, The hyperbranched conjugated polymer is a phenylboronic acid-functionalized cationic hyperbranched conjugated polymer, with the following chemical structural formula: ， Where n represents the number of repeating units, and n is 3 to 9.

2. The hyperbranched conjugated polymer according to claim 1, characterized in that, The hyperbranched conjugated polymer hyperbranched framework is constructed by coupling reaction of electron acceptor unit, electron donor unit and branching unit. The electron acceptor unit is 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole), the electron donor unit is 2,6-bis(trimethyltin)-4H-cyclopenta[2,1-B:3,4-B']dithiophene, and the branching unit is tris(4-bromophenyl)amine.

3. The method for preparing the hyperbranched conjugated polymer according to claim 1, characterized in that, include: S1: A coupling polymerization reaction was carried out using 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) as an electron acceptor unit, 2,6-di(trimethyltin)-4H-cyclopentano[2,1-B:3,4-B']dithiophene as an electron donor unit, and tris(4-bromophenyl)amine as a branching unit to obtain a neutral hyperbranched conjugated polymer; the structural formula of the neutral hyperbranched conjugated polymer is as follows: ； S2: The neutral hyperbranched conjugated polymer obtained in step S1 is subjected to a quaternization reaction with dimethylamine, and then reacted with 3-bromomethylphenylboronic acid to obtain the final product.

4. The method for preparing the near-infrared II absorption and photothermal hyperbranched conjugated polymer according to claim 3, characterized in that, In step S1, the molar ratio of 4,7-bis(2-bromo-5-thienyl)-benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole), 2,6-bis(trimethyltin)-4H-cyclopenta[2,1-B:3,4-B']dithiophene to tri(4-bromophenyl)amine is 1:1:0.2; And / or, in step S2, the molar ratio of the neutral hyperbranched conjugated polymer, dimethylamine, and 3-bromomethylphenylboronic acid is 1:180:

180.

5. The method for preparing the near-infrared II absorption and photothermal effect hyperbranched conjugated polymer according to claim 3, characterized in that, And / or, in step S1, anhydrous toluene is used as the reaction solvent; And / or, in step S1, the reaction conditions are 2-6 hours in an oxygen-free environment at 110°C; And / or, in step S1, (dibenzylacetone)dipalladium and tris(o-methylphenyl)phosphine are added as catalysts during the reaction; And / or, in step S2, the quaternization reaction conditions are: reaction in an ice bath for 1 hour, followed by reaction in an oil bath at 50°C for 3 days; And / or, in step S2, the reaction with 3-bromomethylphenylboronic acid is carried out under anhydrous and oxygen-free conditions for 3 days.

6. The application of the hyperbranched conjugated polymer according to claim 1 or 2 in the antibacterial and antifungal properties of sealants.

7. A silicone sealant comprising a hyperbranched conjugated polymer doped according to claim 1 or 2.

8. The method for preparing the silicone sealant according to claim 7, characterized in that, include: Step 1: The toluene solution of the hyperbranched conjugated polymer in the near-infrared II region is rapidly added to water under ultrasonic conditions and dispersed. Then the dispersion is mixed with the base glue to obtain the masterbatch. Step 2: Mix the obtained masterbatch with the base adhesive, crosslinking agent, filler, catalyst, plasticizer and coupling agent to obtain silicone sealant.

9. The method for preparing the silicone sealant according to claim 8, characterized in that, The base adhesive is α,ω-dihydroxypolydimethylsiloxane, the crosslinking agent is methyltributanone oxime silane, the filler is calcium carbonate, the catalyst is dibutyltin dilaurate, the plasticizer is polydimethylsiloxane, and the coupling agent is γ-aminopropyltriethoxysilane. And / or, the mixing is carried out in a mixer at room temperature; And / or, in step 1, the mass ratio of the hyperbranched conjugated polymer to the base adhesive is 1:5 to 1:100; And / or, in step 2, the mass ratio of masterbatch to base adhesive, crosslinking agent, filler, catalyst, plasticizer, and coupling agent is 0.1:70:5:10:0.1:10:

2.

10. The application of the silicone sealant according to any one of claims 7 to 9 in antibacterial and antifungal applications.

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