Pillar[n]arene derivative-dcoit sustained-release supramolecular self-assembly, applications and preparation methods

Abstract

The application relates to the technical field of supramolecules, in particular to a pillar[n]arene derivative-DCOIT slow-release supramolecular self-assembly body, application and a preparation method. The supramolecular self-assembly body loads DCOIT by taking a pillar[n]arene derivative as a molecular carrier; the pillar[n]arene serving as the carrier can form a supramolecular assembly body with DCOIT through hydrogen bond interaction between pi and CH2, the host-guest complexation of the two is strong, and the pillar[n]arene derivative can effectively control the slow release of DCOIT; the supramolecular self-assembly body is good in safety and stability, low in cost, beneficial to industrialized production, and wide in application field; the method is simple in operation, low in preparation cost, easy to realize, and beneficial to industrial promotion.

Description

Technical Field

[0001] This invention relates to the field of supramolecular technology, and more specifically, to column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assemblies, their applications, and preparation methods. Background Technology

[0002] Marine biofouling refers to the biofouling formed by the adhesion and growth of marine microorganisms, plants, and animals on the surface of marine facilities. It can reduce ship speed, accelerate the corrosion of marine equipment, clog seawater cooling pipes, and affect marine aquaculture production, thus profoundly impacting marine industry and marine development. Therefore, developing environmentally friendly antifouling agents and extending their lifespan has always been an important research topic in the field of marine antifouling technology.

[0003] In the 1990s, Rohm & Hass Corporation of the United States developed and produced an antifouling agent with the chemical name 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), and registered it under the trademark Sea-NineTM 211. DCOIT degrades and disperses rapidly in the environment, accumulates very little in marine environments, has minimal build-up in organisms, and poses little harm to organisms other than the target organism, offering advantages such as environmental friendliness and low toxicity. It provides good protection for ship antifouling and is widely used in antifouling materials. However, DCOIT antifouling agents often exhibit explosive release during use. Initially, the DCOIT content is high, the concentration is high, and the release is rapid, with the release concentration far exceeding the effective concentration for inhibiting marine organisms. Later, the antifouling agent content is low, the concentration is low, and the release is slow, failing to meet the requirements for inhibiting biofouling. Throughout the entire process, the DCOIT antifouling agent is not effectively utilized, significantly shortening the antifouling period.

[0004] Currently, the most widely used methods for sustained-release antifouling agents are microencapsulation-based sustained-release technology, microtubule-based controlled-release technology, and temperature-sensitive chitosan controlled-release technology. However, these sustained-release technologies exhibit significant differences in effectiveness, produce composite materials with poor stability, and involve complex and costly preparation methods, making them unsuitable for industrial application. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled body, its application and preparation method, so as to prevent the explosive release of DCOIT.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0007] This invention provides a column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly, wherein the supramolecular self-assembled assembly uses a column[n]aromatic derivative as a molecular carrier to load DCOIT; the molecular structure of the column[n]aromatic derivative is shown in Formula 1:

[0008]

[0009] Where the value of n is 5 to 15;

[0010] R1 and R2 are independently represented as straight-chain or branched alkyl groups, wherein the number of carbon atoms in the alkyl group is 1 to 10; the alkyl group is substituted or unsubstituted, wherein the substituent in the substituted alkyl group is one or more of halogen, carboxyl, ester, alkynyl, aromatic, and N-containing substituents.

[0011] Based on the above technical solution, the present invention can be further improved as follows.

[0012] Furthermore, the characteristic is that the value of n is 5.

[0013] Furthermore, R1 and R2 are independently represented as -CH3, -CH2CH3, -CH2COOCH3, -CH2CH2CH2Br, -CH2C≡CH, -CH2CH2COOH,

[0014] Furthermore, both R1 and R2 are represented as -CH3.

[0015] Furthermore, the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly was used to prepare an antifouling additive.

[0016] Furthermore, the additive is a coating additive, paint additive, latex paint additive, rubber additive, plastic additive, lubricant additive, or wood additive.

[0017] The present invention also provides a method for preparing the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly as described above, wherein the organic solution of DCOIT is stirred and added dropwise to the organic solution of the column[n]aromatic derivative for reaction, and after removing the organic solvent, the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly is obtained.

[0018] Furthermore, the molar ratio of the column[n]aromatic derivative to the DCOIT is 1:1.02-1.2.

[0019] Furthermore, the following steps are included:

[0020] S1. The column[n]aromatic derivative is added to a first organic solvent and stirred to dissolve, thereby obtaining an organic solution of the column[n]aromatic derivative; the mass-to-volume ratio of the column[n]aromatic derivative to the first organic solvent is 1g:55-60ml;

[0021] S2. Add the DCOIT to the second organic solvent and stir to dissolve it to obtain an organic solution of the DCOIT; the mass-to-volume ratio of the DCOIT to the second organic solvent is 1g:8-12ml;

[0022] S3. Stir the organic solution of the column[n] aromatic hydrocarbon derivative, and simultaneously add the organic solution of DCOIT dropwise to the organic solution of the column[n] aromatic hydrocarbon derivative; the dropping rate is 1-2 drops / second;

[0023] S4. After the addition is complete, a reaction solution is obtained. The solvent in the reaction solution is removed to obtain the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled body.

[0024] Furthermore, the first organic solvent and the second organic solvent may be the same or different; the first organic solvent and the second organic solvent are one or more of dichloromethane, chloroform, N,N-dimethylformamide, N,N-dimethylacetamide, methanol, ethanol, and acetone, respectively.

[0025] The beneficial effects of this invention are as follows:

[0026] (1) The column[n]arene derivative-DCOIT sustained-release supramolecular self-assembly of the present invention, wherein the column[n]arene as the carrier can form a supramolecular assembly with DCOIT through hydrogen bonding between π···CH2, and can effectively control the sustained release of DCOIT.

[0027] (2) The column[n] aromatic derivative-DCOIT sustained-release supramolecular self-assembly of the present invention has a strong host-guest complexation effect between the column[n] aromatic derivative and DCOIT and a high complexation constant;

[0028] (3) The column[n] aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly of the present invention has a loading rate of up to 99% for column[n] aromatic derivative and DCOIT.

[0029] (4) The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled structure of the present invention has a stable DCOIT release rate over time and has a good sustained-release effect.

[0030] (5) The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly of the present invention has good safety, good stability, and low cost, which is conducive to industrial production;

[0031] (6) The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly of the present invention. The supramolecular self-assembly sustained-release material obtained by the present invention can not only be used in marine antifouling coatings, but also in various industrial fields such as rubber, plastics, fibers, lubricating oil, and wood industry.

[0032] (7) The preparation method of the column [n] aromatic derivative-DCOIT sustained-release supramolecular self-assembly of the present invention is simple to operate, low in preparation cost, easy to implement, and conducive to industrial promotion. Attached Figure Description

[0033] Figure 1 The column[n]arene derivative-DCOIT sustained-release supramolecular self-assembly of the present invention is shown in the example, which is a schematic diagram of the molecular structure of the all-methoxy column[5]arene-DCOIT sustained-release self-assembly. Figure 1 In this context, 'a' represents the molecular structural formula. Figure 1 b and c are schematic diagrams of the three-dimensional structure simulation from different perspectives;

[0034] Figure 2 The present invention is a column[n]arene derivative-DCOIT sustained-release supramolecular self-assembled assembly. In the examples, the NMR titration diagram of the all-methoxy column[5]arene-DCOIT sustained-release self-assembled assembly is shown.

[0035] Figure 3 The present invention is a column[n]arene derivative-DCOIT sustained-release supramolecular self-assembled assembly. In the examples, the sustained-release curve of the all-methoxy column[5]arene-DCOIT sustained-release self-assembled assembly in simulated seawater is shown. Detailed Implementation

[0036] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0037] The column [n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly of the present invention can be represented as follows: DCOIT was loaded using column[n]aromatic derivatives as molecular supports; the molecular structure of the column[n]aromatic derivatives is shown in Formula 1:

[0038]

[0039] Where the value of n is 5 to 15;

[0040] R1 and R2 are independently represented as straight-chain or branched alkyl groups, in which the number of carbon atoms is 1 to 10; the alkyl group is substituted or unsubstituted, and in substituted alkyl groups, the substituent is one or more of halogen, carboxyl, ester, alkynyl, aromatic, and N-containing substituents.

[0041] The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly of the present invention utilizes column[n]aromatics as a carrier to form a supramolecular assembly with DCOIT through hydrogen bonding between π···CH2 groups, effectively controlling the sustained release of DCOIT. This supramolecular self-assembled assembly possesses advantages such as good safety, good stability, low cost, and suitability for industrial production; it can be used not only in marine antifouling coatings but also in various industrial fields such as rubber, plastics, fibers, lubricants, and wood.

[0042] The column [n]aromatic derivative of this invention, DCOIT, is a sustained-release supramolecular self-assembled compound belonging to the supramolecular family. The advent of supramolecular chemistry was epoch-making in the chemical community, revealing that molecules are no longer the smallest units that retain physical properties, and that function arises within supramolecular assemblies. The main research object of supramolecular chemistry is the non-covalent interaction between molecules. Compared to the covalent bonds studied in traditional chemistry, the non-covalent bonds studied in supramolecular chemistry have weaker bond energies and are reversible. Examples include hydrogen bonds, metal coordination, van der Waals forces, and π-π interactions. The study of supramolecular chemistry has elucidated new concepts such as molecular self-assembly, molecular recognition, and host-guest chemistry. Column [n]aromatics are a class of cyclic, symmetrical "column"-type next-generation macrocyclic molecules formed by the para-linking of hydroquinone or hydroquinone ethers with methylene groups on the benzene ring. Due to their simple synthesis methods, ease of functionalization, symmetrical columnar cavity structure, and strong host-guest recognition ability, they have experienced rapid development in recent years, attracting great attention from the supramolecular chemistry community. These characteristics of columnar [n]aromatics give them great advantages in constructing supramolecular materials, making them widely used in supramolecular polymers, supramolecular self-assembly, supramolecular organic framework materials, supramolecular probes and molecular carriers.

[0043] Preferably, R1 and R2 are independently represented as -CH3, -CH2CH3, -CH2COOCH3, -CH2CH2CH2Br, -CH2C≡CH, -CH2CH2COOH,

[0044] Preferably, in Formula 1 above, both R1 and R2 are represented as -CH3.

[0045] Preferably, in Equation 1 above, the value of n is 5.

[0046] DCOIT is 4,5-dichloro-2-n-octyl-3(2H)isothiazolidinone, with the following structural formula:

[0047]

[0048] Preferably, the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly is used to prepare antifouling additives, which gives the antifouling additives a good sustained-release effect and can effectively extend the service life of the antifouling additives.

[0049] Preferably, the antifouling additive is a coating additive, paint additive, latex paint additive, rubber additive, plastic additive, lubricant additive, or wood additive. The preparation method of the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly of the present invention involves stirring an organic solution of DCOIT and adding it dropwise to an organic solution of the column[n]aromatic derivative. After removing the organic solvent, the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembly is obtained.

[0050] The above method is simple to operate, low in cost, and conducive to industrial application. The resulting supramolecular self-assembled bodies have advantages such as good stability and good sustained-release effect.

[0051] Preferably, in the above method, the molar ratio of column[n]aromatic derivative to DCOIT is 1:1.02-1.2.

[0052] Specifically, the method of the present invention includes the following steps:

[0053] S1. Add the column[n] aromatic hydrocarbon derivative to the first organic solvent and stir to dissolve to obtain an organic solution of the column[n] aromatic hydrocarbon derivative.

[0054] The mass-to-volume ratio of the column[n]aromatic derivative to the first organic solvent is determined by the standard that the first organic solvent can dissolve the column[n]aromatic derivative. Specifically, the mass-to-volume ratio of the column[n]aromatic derivative to the first organic solvent is 1 g: 55–60 ml.

[0055] S2. Add DCOIT to the second organic solvent and stir to dissolve to obtain an organic solution of DCOIT.

[0056] The mass-to-volume ratio of DCOIT to the second organic solvent is determined by ensuring that the second organic solvent can dissolve DCOIT. Specifically, the mass-to-volume ratio of DCOIT to the second organic solvent is 1 g: 2–8 ml.

[0057] In steps S1 and S2 above, preferably, the first organic solvent and the second organic solvent are the same or different; the first organic solvent and the second organic solvent are one or more of dichloromethane, chloroform, N,N-dimethylformamide, N,N-dimethylacetamide, methanol, ethanol, and acetone.

[0058] S3. Stir the organic solution of the [n] aromatic hydrocarbon derivative in the column, and simultaneously add the organic solution of DCOIT dropwise into the organic solution of the [n] aromatic hydrocarbon derivative in the column.

[0059] Preferably, the organic solution of DCOIT is added slowly at a rate of 1 to 2 drops per second.

[0060] S4. After the addition is complete, a reaction solution is obtained. The solvent in the reaction solution is removed to obtain the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled body.

[0061] Preferably, the solvent is removed by rotary evaporation.

[0062] The present invention will be described below through specific embodiments. Unless otherwise specified, the raw materials used in the embodiments are all conventional raw materials that can be obtained commercially; unless otherwise specified, the methods used in the embodiments are all prior art.

[0063] Example

[0064] The carrier of the supramolecular self-assembly in this embodiment is a fully methoxy columnar aromatic hydrocarbon [5], that is, in Formula 1, n is 5, and R1 and R2 are both represented as -CH3.

[0065] The specific steps for preparing the supramolecular self-assembled structure in this embodiment are as follows:

[0066] (1) Weigh 0.5010g of all-methoxy[5] aromatic hydrocarbons and add them to 30mL of dichloromethane. Stir to dissolve and obtain an all-methoxy[5] aromatic hydrocarbon-dichloromethane solution.

[0067] (2) Weigh 0.1881 g of DCOIT, add it to 2 mL of dichloromethane, stir to dissolve, and obtain DCOIT-dichloromethane solution.

[0068] (3) Under stirring conditions, the all-methoxy-column[5]arene-dichloromethane solution was slowly added dropwise to the DCOIT-dichloromethane solution at a rate of 1 drop / second. After the addition was completed, the solvent was removed by rotary evaporation to obtain a supramolecular self-assembled structure mainly composed of all-methoxy-column[5]arene.

[0069] The structure of the DCOIT sustained-release self-assembled assembly prepared in this embodiment, using all-methoxy-column [5] aromatic hydrocarbons as molecular carriers, is as follows: Figure 1 As shown. Figure 1 In this context, 'a' represents the molecular structural formula. Figure 1 Figures b and c in the diagram are schematic diagrams of the three-dimensional structure simulation from different perspectives. Figure 1 As can be seen, the alkyl chain of DCOIT passes through the all-methoxy column[5] aromatic hydrocarbon, and DCOIT is encapsulated inside the cavity of the all-methoxy column[5] aromatic hydrocarbon, thus forming an assembly. According to calculations using high-performance liquid chromatography, the loading rate of this supramolecular self-assembled structure is as high as 99%.

[0070] The NMR titration diagram of the DCOIT sustained-release assembly prepared in this embodiment, using all-methoxy-column[5]arene as a molecular carrier, is shown below. Figure 2 As shown.

[0071] The structural formula of the all-methoxy columnar aromatic hydrocarbon in this embodiment is shown in Formula 2:

[0072]

[0073] In this embodiment, the H on the alkyl chain in the molecular formula of DCOIT is labeled as shown in Formula 3:

[0074]

[0075] In deuterated chloroform NMR solution, due to the π···CH2 hydrogen bonding between the all-methoxy[5] aromatic hydrocarbon and the DCOIT guest molecule, a set of 1H NMR spectra of the guest molecule DCOIT with the change of the concentration of the host molecule all-methoxy[5] aromatic hydrocarbon was obtained when the concentration of the host molecule all-methoxy[5] aromatic hydrocarbon was 4mM-43mM (e.g. Figure 2 As shown). Analysis revealed that with the increase of the concentration of the all-methoxy column[5] aromatic host, the proton H1 in the host P[5] benzene ring region shifts to the lower field due to the enhanced intermolecular forces, and the H on the alkyl chain of DCOIT a H b H c H d H e H f H g The chemical shift moves to a higher field and gradually widens, which is due to the signal shielding caused by the alkyl chain of DCOIT entering the cavity of the all-methoxy column[5] aromatic hydrocarbon. This demonstrates effective host-guest complexation, where the complexation constant K between the all-methoxy column[5] aromatic hydrocarbon and DCOIT is... a = (0.217 ± 0.004) × 10 2 M -1 .

[0076] The slow-release curve of the DCOIT sustained-release supramolecular self-assembled assembly with all-methoxy columnar[5] aromatics as the main molecule prepared in this embodiment in simulated seawater is as follows: Figure 3 As shown. From Figure 3 As can be seen from this, self-assembly The release rate showed a good linear relationship, indicating that the assembly The outward diffusion behavior of DCOIT in the medium is very stable. Figure 3It can be observed that by day 22, the release rate of DCOIT began to slow down, and by day 28, the release rate of DCOIT was basically balanced, with a release rate of 39%, and the release amount was less than half of the loading amount. This indicates that the DCOIT slow-release supramolecular self-assembled molecule with all-methoxy columnar aromatics as the main molecule [5] Its anti-fouling effect is long-lasting.

[0077] Overall, the above experiments show that DCOIT releases from P[5] at a stable rate, avoiding burst release, achieving a slow-release effect and a long-lasting anti-fouling effect.

[0078] Regarding the specific structure of the column[n]aromatic derivative, the above examples verified its complexation with DCOIT when n is 5. When n is greater than 5, the number of aromatics in the column[n]aromatic derivative increases. Since the column[n]aromatic derivative and DCOIT mainly enter the aromatic cavity through the alkyl chain of DCOIT, the complexation effect is better when the number of aromatics increases, which is more conducive to the sustained release of DCOIT. However, when the number of aromatics is too large, for example, when n is greater than 15, the aromatic cavity is too large, which leads to a decrease in the complexation ability between the column[n]aromatic derivative and DCOIT, resulting in an excessively fast release rate and a shorter lifespan of DCOIT.

[0079] For the specific substituents in the column[n]aromatic derivatives, the above examples verified the case where both R1 and R2 are -CH3. In the column[n]aromatic derivatives, different substituents have varying degrees of influence on the self-assembly of the column[n]aromatic derivative and DCOIT. When R1 and R2 are straight-chain or branched alkyl groups, these substituents may compete with the alkyl chain of DCOIT as the carbon chain grows. When R1 and R2 contain other substituents such as halogens, carboxyl groups, ester groups, or alkyne groups, the presence of electronic effects will have a certain impact on the formation of supramolecular assemblies. In particular, electron-deficient groups such as halogens will reduce the electron cloud density on the benzene ring of the column[n]aromatic, negatively affecting the formation of supramolecular self-assemblies. Furthermore, when the alkyl length is too long or the branches and substituents are too complex, it will affect complexation, leading to a decrease in the loading rate of DCOIT.

[0080] When R1 and R2 are substituents containing aromatic rings, such as benzyl and pyrene, these substituents have aromatic rings, and the electron cloud density on the benzene ring is greater. The π···CH2 hydrogen bonding between them will be stronger, which is more conducive to the formation of supramolecular assemblies.

[0081] In the description of this invention, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0082] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A columnar[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly, characterized in that, The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly uses the column[n]aromatic derivative as a molecular carrier to load DCOIT; the molecular structure of the column[n]aromatic derivative is shown in Formula 1: Formula 1 Where n is 5; R1 and R2 are both represented as -CH3.

2. The application of the column [n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly as described in claim 1, characterized in that, The column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly is used to prepare antifouling additives.

3. The application of the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly according to claim 2, characterized in that, The antifouling additive is a coating additive, rubber additive, plastic additive, lubricating oil additive, or wood additive.

4. A method for preparing the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly as described in claim 1, characterized in that, The organic solution of DCOIT was stirred and added dropwise to the organic solution of the column[n]arene derivative to carry out the reaction. After removing the organic solvent, the column[n]arene derivative-DCOIT sustained-release supramolecular self-assembled body was obtained.

5. The method for preparing a column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly according to claim 4, characterized in that, The molar ratio of the column[n]aromatic derivative to the DCOIT is 1:1.02-1.

2.

6. The method for preparing a column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly according to claim 5, characterized in that, Includes the following steps: S1. The column[n] aromatic derivative is added to a first organic solvent and stirred to dissolve, thereby obtaining an organic solution of the column[n] aromatic derivative; the mass-to-volume ratio of the column[n] aromatic derivative to the first organic solvent is 1g:55~60ml; S2. Add the DCOIT to the second organic solvent and stir to dissolve it to obtain an organic solution of the DCOIT; the mass-to-volume ratio of the DCOIT to the second organic solvent is 1g:2~8ml; S3. Stir the organic solution of the column[n] aromatic hydrocarbon derivative, and simultaneously add the organic solution of DCOIT dropwise to the organic solution of the column[n] aromatic hydrocarbon derivative to carry out the reaction; the dropping rate is 1~2 drops / second; S4. After the addition is complete, a reaction solution is obtained. The solvent in the reaction solution is removed to obtain the column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled body.

7. The method for preparing a column[n]aromatic derivative-DCOIT sustained-release supramolecular self-assembled assembly according to claim 6, characterized in that, The first organic solvent and the second organic solvent may be the same or different; the first organic solvent and the second organic solvent are one or more of dichloromethane, trichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, methanol, ethanol, and acetone.

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