Circularly polarized luminescent supramolecular assemblies, polymer thin films and methods of making and using the same

Abstract

The application discloses a circularly polarized luminescent supramolecular assembly, a polymer film and a preparation method and application thereof. The supramolecular assembly comprises an organic small molecule as a single chiral building block, a zinc salt and an achiral fluorescent dye; the organic small molecule, the zinc salt and the achiral fluorescent dye form the supramolecular assembly with the circularly polarized luminescent property through a supramolecular assembly process. The polymer film comprises the supramolecular assembly and an organic high polymer; the supramolecular assembly is mixed with a mother liquor of the organic high polymer to form a precursor of the polymer film. The single chiral building unit is used as a chiral donor to realize construction of the circularly polarized luminescent material with opposite chirality; the product has the performance of chirality amplification and light stability enhancement; the preparation method is simple and convenient to operate and is suitable for large-scale production.

Description

Technical Field

[0001] This invention relates to the field of luminescent materials technology, and more specifically, to supramolecular assemblies, polymer films, and their preparation methods and applications that emit circularly polarized light. Background Technology

[0002] Circularly polarized luminescent (CPL) materials have attracted considerable attention due to their potential applications in chiral sensing, encrypted information transmission and storage, and 3D displays. Among the various methods for constructing CPL-active materials, supramolecular assembly stands out for its excellent versatility and significantly enhanced luminescence asymmetry factor (g). lum The use of chiral components to construct CPL materials is considered a promising method for their preparation due to their chiral properties and stimulus responsiveness. In constructing CPL materials using supramolecular assembly, most multicolor left- or right-handed circularly polarized luminescent materials are obtained from co-assemblies of chiral donors with enantiomers and different achiral fluorescent dyes. However, this method requires two chiral groups (a pair of enantiomers), which means that the preparation process involves lengthy ligand synthesis and cumbersome material preparation. Therefore, the ideal method for constructing multicolor left- or right-handed circularly polarized luminescent materials is to use a single chiral building block to achieve the preparation of materials with opposite chirality. Furthermore, solid materials have significant advantages in practical applications compared to soft gels or other supramolecular assemblies in solution. Therefore, using a single chiral building block to realize solid films with multicolor left- or right-handed circularly polarized luminescence properties not only provides a simple and universal strategy for constructing circularly polarized luminescent materials but also lays the foundation for their wide application. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a circularly polarized luminescent supramolecular assembly, a polymer film, and their preparation methods and applications. The aim is to provide a simple and universal method for constructing a chiral reversible full-color circularly polarized luminescent supramolecular assembly and film material using a single chiral building unit, which can exhibit rich colors and chiral variations.

[0004] To achieve the above objectives, in a first aspect, the present invention provides a supramolecular assembly with circularly polarized light emission, characterized in that: it comprises an organic small molecule, a zinc salt, and an achiral fluorescent dye as single chiral building blocks; the organic small molecule, the zinc salt, and the achiral fluorescent dye form a supramolecular assembly with circularly polarized light emission properties through a supramolecular assembly process.

[0005] Furthermore, the organic small molecule is pyridyl-vinyl cholesterol (PVPCC). As a single chiral building block, the organic small molecule has cholesterol as a chiral unit and the pyridyl group for metal coordination.

[0006] Further, the zinc salt includes one of zinc chloride (ZnCl2), zinc nitrate (Zn(NO3)2), and zinc acetate (Zn(AcO)2). The zinc salt is used to provide zinc ions in the supramolecular assembly to coordinate with the pyridine group moiety of the small organic molecule.

[0007] Further, the non-chiral fluorescent dyes include one or more of π-conjugated dyes, rhodamine dyes, cyanide dyes, and AIE (aggregation-induced emission) dyes; wherein, the π-conjugated dyes include one or more of 9,10-diphenylethynylanthracene (BPEA), anthracene, and perylene; the rhodamine dyes include one or more of rhodamine 6G (Rh6G) and rhodamine B (RhB); the cyanide dyes include one or more of Cy3, Cy3.3, Cy5, Cy5.5, Cy7, and Cy7.5; and the AIE dyes include one or more of tetraphenylethylene series and cyanodiethylene ((2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(4-hydroxyphenyl)acrylonitrile), α-DCS).

[0008] In a second aspect, the present invention provides a circularly polarized light-emitting polymer film, characterized in that it comprises an organic polymer and the aforementioned supramolecular assembly; the supramolecular assembly is mixed with the mother liquor of the organic polymer to form a precursor of the polymer film.

[0009] Furthermore, the organic polymer is one of polymethyl methacrylate (PMMA), polyimide resin (PI), and polycaprolactone (PCL). The present invention requires that the organic polymer meet the following conditions: the solvent required for preparing the mother liquor must be consistent with the solvent of the supramolecular assembly, and it must exhibit good film-forming properties in that solvent environment.

[0010] Thirdly, the present invention provides a method for preparing the above-mentioned supramolecular assembly, characterized by comprising the following steps:

[0011] Step S11: Prepare a mother liquor of a certain concentration by adding solvents to the organic small molecule, zinc salt and non-chiral fluorescent dye respectively;

[0012] Step S12: Add an appropriate amount of the mother liquor of the organic small molecule and the mother liquor of the non-chiral fluorescent dye to the sample bottle and mix thoroughly by ultrasonication.

[0013] Step S13: Add an appropriate amount of the zinc salt mother liquor to the sample bottle, mix it evenly by ultrasonication at room temperature, then heat the mixture to dissolve it, and then let it stand at room temperature or under ice bath conditions to obtain the supramolecular assembly.

[0014] Further, in step S11, the solvent of the mother liquor for the small organic molecule is p-xylene, with a concentration of 22.8 mM, 32.8 mM, or 42.8 mM; the solvent of the mother liquor for the achiral fluorescent dye is n-butanol, with a concentration of 2.28 mM, 3.28 mM, or 4.28 mM; and the solvent of the mother liquor for the zinc salt is a mixture of p-xylene and n-butanol, with a concentration of 11.4 mM, 16.4 mM, or 21.4 mM.

[0015] Fourthly, the present invention provides a method for preparing the above-mentioned polymer film, characterized by comprising the following steps:

[0016] Step S21: Prepare a mother liquor of a certain concentration by adding solvents to the organic small molecule, zinc salt and non-chiral fluorescent dye respectively;

[0017] Step S22: Add an appropriate amount of the mother liquor of the organic small molecule and the mother liquor of the non-chiral fluorescent dye to the sample bottle and mix thoroughly by ultrasonication.

[0018] Step S23: Add an appropriate amount of the zinc salt mother liquor to the sample bottle, mix it evenly by ultrasonication at room temperature, then heat the mixture to dissolve it, and then let it stand at room temperature or under ice bath conditions to obtain supramolecular assembly;

[0019] Step S24: Add the supramolecular assembly to the mother liquor of the organic polymer and stir until homogeneous to obtain a mixture; drop the mixture onto a flat surface and wait for the solvent to evaporate completely to obtain a polymer film.

[0020] Further, in step S21, the solvent of the mother liquor for the small organic molecule is p-xylene, with a concentration of 22.8 mM, 32.8 mM, or 42.8 mM; the solvent of the mother liquor for the achiral fluorescent dye is n-butanol, with a concentration of 2.28 mM, 3.28 mM, or 4.28 mM; the solvent of the mother liquor for the zinc salt is a mixed solvent of p-xylene and n-butanol, with a concentration of 11.4 mM, 16.4 mM, or 21.4 mM; and the solvent of the mother liquor for the organic polymer in step S24 is a mixed solvent of p-xylene and n-butanol, with a concentration of 100 mg / mL, 120 mg / mL, or 140 mg / mL.

[0021] Finally, the present invention provides an application of the above-mentioned supramolecular assembly or polymer film as a circularly polarized light-emitting material.

[0022] Compared with the prior art, the above invention has the following advantages or beneficial effects:

[0023] (1) This invention uses a single chiral building unit as a chiral donor. By using a supramolecular chiral co-assembly strategy, the external stimulus response of the supramolecular assembly can be utilized to realize the construction of circularly polarized luminescent materials with opposite chirality.

[0024] (2) The circularly polarized light-emitting polymer film provided by the present invention has properties such as chiral amplification and enhanced photostability;

[0025] (3) The preparation method provided by the present invention is simple and convenient to operate and is suitable for large-scale production. Attached Figure Description

[0026] The invention, its features and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0027] Figure 1 PVPCC / Zn prepared under room temperature static conditions in one embodiment of the present invention 2+ Scanning electron microscope (SEM) images and size statistics of / dyes supramolecular assemblies;

[0028] Figure 2 In one embodiment of the present invention, an organic polymer doped with PVPCC / Zn was prepared under room temperature and static conditions. 2+ Photographs of polymer films from / dyes;

[0029] Figure 3 PVPCC / Zn prepared under ice bath static conditions in one embodiment of the present invention 2+ Scanning electron microscope (SEM) images and size statistics of / dyes supramolecular assemblies;

[0030] Figure 4 In one embodiment of the present invention, an organic polymer doped with PVPCC / Zn was prepared under ice bath static conditions. 2+ Photographs of polymer films from / dyes;

[0031] Figure 5 PVPCC / Zn is an embodiment of the present invention. 2+ CPL spectra of / dyes supramolecular assemblies under static conditions at different temperatures;

[0032] Figure 6 In one embodiment of the present invention, an organic polymer doped with PVPCC / Zn 2+ CPL spectra of / dyes polymer films after standing at different temperatures. Detailed Implementation

[0033] The technical solutions in the embodiments will be clearly and completely described below. Obviously, the embodiments described below are only some embodiments of the present invention, and not all embodiments.

[0034] The terms “comprising,” “including,” and any variations thereof in the following embodiments and comparative examples are intended to cover non-exclusive inclusion, such as a process, method, or product that includes a series of steps or units but is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, or products.

[0035] In addition, unless otherwise specified, the experimental methods shown in the following examples are conventional methods; and the materials and reagents mentioned are commercially available unless otherwise specified.

[0036] Example 1: PVPCC / Zn obtained under room temperature and static conditions 2+ / dyes supramolecular assemblies and their polymer films

[0037] Experimental methods:

[0038] 1.1 Add a certain amount of n-butanol mother liquor of non-chiral fluorescent dye to p-xylene mother liquor of PPVPCC and mix thoroughly by ultrasonication; the total volume of solvent is 100-200 μL, the molar ratio of PPVPCC to fluorescent dye is 10:1, and the ultrasonic power is 100-200 W.

[0039] 1.2. Add an appropriate amount of Zn to the above mixture. 2+ The p-xylene / n-butanol mother liquor was ultrasonically mixed at room temperature, then heated at 363 K for 1 min to dissolve the mixture. After standing at room temperature for a period of time, rod-shaped supramolecular assemblies with an average length of 4.65–8.56 μm were obtained. Figure 1 The total volume of solvent is 300–400 μL, and the mixture consists of PVPCC and Zn. 2+ The molar ratio is 2:1.

[0040] 1.3. Apply the obtained PVPCC / Zn 2+ / α-DCS、PVPCC / Zn 2+ / BPEA、PVPCC / Zn 2+ / Rh6G、PVPCC / Zn 2+An organic polymer mother liquor was added to the / RhB supramolecular co-assembly system, and the mixture was stirred using a vortex mixer to obtain a homogeneous mixture. The organic polymer was one of polymethyl methacrylate (PMMA), polyimide resin (PI), or polycaprolactone (PCL). As an example, PMMA was used in this embodiment. The homogeneous mixture was then dropped into a glass petri dish, and after the solvent had completely evaporated, organic polymer-doped PVPCC / Zn was obtained. 2+ / dyes polymer film ( Figure 2 ).

[0041] Example 2: PVPCC / Zn obtained under ice bath static conditions 2+ / dyes supramolecular assemblies and their polymer films

[0042] Experimental methods:

[0043] 1.1 Add a certain amount of n-butanol mother liquor of non-chiral fluorescent dye to p-xylene mother liquor of PPVPCC and mix thoroughly by ultrasonication; the total volume of solvent is 100-200 μL, the molar ratio of PPVPCC to fluorescent dye is 10:1, and the ultrasonic power is 100-200 W.

[0044] 1.2. Add an appropriate amount of Zn to the above mixture. 2+ The p-xylene / n-butanol mother liquor was ultrasonically mixed at room temperature, then heated at 363 K for 1 min to dissolve the mixture. Afterward, the mixture was allowed to stand in an ice bath for a period of time to obtain rod-shaped supramolecular assemblies with an average length of 0.93–1.15 μm. Figure 3 The total volume of solvent is 300–400 μL, and the mixture consists of PVPCC and Zn. 2+ The molar ratio is 2:1.

[0045] 1.3. Apply the obtained PVPCC / Zn 2+ / α-DCS、PVPCC / Zn 2+ / BPEA、PVPCC / Zn 2+ / Rh6G、PVPCC / Zn 2+ PMMA stock solution was added to the supramolecular co-assembly system of / RhB, and the mixture was stirred evenly using a vortex mixer. The homogeneous mixture was then dropped into a glass petri dish, and after the solvent had completely evaporated, organic polymer-doped PVPCC / Zn was obtained. 2+ / dyes polymer film ( Figure 4 ).

[0046] Example 3: PVPCC / Zn 2+ Circular polarization luminescence of / dyes supramolecular assemblies

[0047] Experimental methods:

[0048] The circularly polarized emission spectrum was detected by placing the PVPCC / Zn obtained in Examples 1 and 2 under room temperature and ice bath conditions. 2+ / dyes supramolecular assemblies were placed in a circular polarization spectrometer to measure their chiral luminescence.

[0049] Experimental results:

[0050] Circularly polarized emission spectra of supramolecular assemblies obtained by static treatment at room temperature and in an ice bath. Figure 5 Analysis revealed that supramolecular assemblies co-assembled with different dyes prepared at room temperature exhibited multicolor right-handed circularly polarized luminescence, while supramolecular co-assemblies prepared under ice bath conditions exhibited multicolor left-handed circularly polarized luminescence.

[0051] Example 4: PVPCC / Zn doped with organic polymers 2+ Circularly polarized luminescence of / dyes polymer thin films

[0052] Experimental methods:

[0053] The detection of circularly polarized emission spectra involved PPVPCC / Zn doped with organic polymers obtained in Examples 1 and 2 under room temperature and ice bath conditions. 2+ / dyes polymer films were placed in a circular polarization spectrometer to measure their chiral luminescence.

[0054] Experimental results:

[0055] Circularly polarized emission spectra of polymer films obtained by standing at room temperature and in an ice bath. Figure 6 Analysis revealed that polymer films prepared at room temperature exhibited multi-colored right-handed circularly polarized luminescence, while polymer films prepared under ice bath conditions exhibited multi-colored left-handed circularly polarized luminescence.

[0056] As can be seen from the test results of the above embodiments and application examples, the present invention can prepare a series of chiral reversible full-color circularly polarized luminescent supramolecular assemblies and flexible polymer films through a relatively simple synthesis method, thereby reducing the construction cost of circularly polarized luminescent materials. It has properties such as chiral amplification and enhanced photostability, and has strong compatibility and wide range of applications.

[0057] In summary, this invention discloses a supramolecular assembly with circularly polarized luminescence, a polymer film, its preparation method, and its applications. The supramolecular assembly comprises a small organic molecule, a zinc salt, and a achiral fluorescent dye as single chiral building blocks; the small organic molecule, zinc salt, and achiral fluorescent dye form a supramolecular assembly with circularly polarized luminescence properties through a supramolecular assembly process. The polymer film comprises the supramolecular assembly and an organic polymer; the mother liquor of the supramolecular assembly and the organic polymer is mixed to form the precursor of the polymer film. This invention uses a single chiral building unit as a chiral donor to achieve the construction of circularly polarized luminescent materials with opposite chirality; the product exhibits chiral amplification and enhanced photostability; the preparation method is simple and convenient, suitable for large-scale production.

[0058] Those skilled in the art should understand that variations can be implemented by combining existing technology with the above embodiments, which will not be elaborated here. Such variations do not affect the essence of the present invention, and will not be elaborated here either.

[0059] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and the devices and structures not described in detail should be understood as being implemented in a conventional manner in the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. This does not affect the essential content of the present invention. Therefore, any simple 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 present invention's technical solutions still fall within the protection scope of the present invention.

Claims

1. A circularly polarized luminescent supramolecular assembly, characterized in that: The application relates to a circularly polarized luminescent material, which comprises an organic small molecule pyridylvinylcholesterol as a single chiral building block, a zinc salt and an achiral fluorescent dye; the organic small molecule pyridylvinylcholesterol, the zinc salt and the achiral fluorescent dye form a supramolecular assembly with circularly polarized luminescent properties through a supramolecular assembly process; and the supramolecular assembly is prepared by the following steps. In step S11, the pyridylvinylcholesterol, the zinc salt and the achiral fluorescent dye are respectively prepared into mother liquor of a certain concentration by adding solvents. In step S12, the pyridylvinylcholesterol mother liquor and the achiral fluorescent dye mother liquor are added into a sample bottle, and then ultrasonic mixing is performed to obtain uniformity. In step S13, the zinc salt mother liquor is added into the sample bottle, and then ultrasonic mixing is performed at room temperature to obtain uniformity; then the mixture is heated to dissolve and clear; and then the mixture is left to stand at room temperature or in an ice bath to obtain the supramolecular assembly; the supramolecular assembly prepared at room temperature is right-handed; and the supramolecular assembly prepared in an ice bath is left-handed. The solvent of the mother liquor of the pyridylvinyl cholesterols in the step S11 is p-xylene, and the concentration is one of 22.8 mM, 32.8 mM and 42.8 mM; the solvent of the mother liquor of the achiral fluorescent dye is n-butanol, and the concentration is one of 2.28 mM, 3.28 mM and 4.28 mM; the solvent of the mother liquor of the zinc salt is a mixed solvent of p-xylene and n-butanol, and the concentration is one of 11.4 mM, 16.4 mM and 21.4 mM; the molar ratio of the pyridylvinyl cholesterols to the achiral fluorescent dye is 10:1; and the molar ratio of the pyridylvinyl cholesterols to Zn 2+ 2:

1. 2+ The solvent of the mother liquor of the pyridylvinyl cholesterols in the step S11 is p-xylene, and the concentration is one of 22.8 mM, 32.8 mM and 42.8 mM; the solvent of the mother liquor of the achiral fluorescent dye is n-butanol, and the concentration is one of 2.28 mM, 3.28 mM and 4.28 mM; the solvent of the mother liquor of the zinc salt is a mixed solvent of p-xylene and n-butanol, and the concentration is one of 11.4 mM, 16.4 mM and 21.4 mM; the molar ratio of the pyridylvinyl cholesterols to the achiral fluorescent dye is 10:1; and the molar ratio of the pyridylvinyl cholesterols to Zn 2+ 2:

1.

2. The circularly polarized luminescent supramolecular assembly according to claim 1, characterized in that, The zinc salt is one of zinc chloride, zinc nitrate and zinc acetate.

3. The circularly polarized luminescent supermolecular assembly according to claim 1, characterized in that, The achiral fluorescent dye comprises one or more of pi-conjugated dyes, rhodamine dyes, cyanine dyes and AIE dyes; the pi-conjugated dyes comprise one or more of 9,10-diphenylacetylenyl anthracene, anthracene and perylene; the rhodamine dyes comprise one or more of rhodamine 6G and rhodamine B; the cyanine dyes comprise one or more of Cy3, Cy3.3, Cy5, Cy5.5, Cy7 and Cy7.5; and the AIE dyes comprise one or more of tetraphenyl ethylene series and cyano diethylene series.

4. A circularly polarized light-emitting polymer thin film, characterized by, The application further relates to a circularly polarized luminescent material, which comprises an organic high polymer and the supramolecular assembly of any one of claims 1 to 3; the supramolecular assembly is mixed with the mother liquor of the organic high polymer to form a precursor of a polymer film; and the polymer film is prepared by the following steps. In step S21, the pyridylvinylcholesterol, the zinc salt and the achiral fluorescent dye are respectively prepared into mother liquor of a certain concentration by adding solvents. In step S22, the pyridylvinylcholesterol mother liquor and the achiral fluorescent dye mother liquor are added into a sample bottle, and then ultrasonic mixing is performed to obtain uniformity. In step S23, the zinc salt mother liquor is added into the sample bottle, and then ultrasonic mixing is performed at room temperature to obtain uniformity; then the mixture is heated to dissolve and clear; and then the mixture is left to stand at room temperature or in an ice bath to obtain the supramolecular assembly. In step S24, the supramolecular assembly is added into the mother liquor of the organic high polymer, and then stirring is performed to obtain a mixture; the mixture is dropped onto a flat surface, and then a polymer film is obtained after the solvent is completely volatilized; the polymer film prepared by using the supramolecular assembly prepared at room temperature as raw material is right-handed; and the polymer film prepared by using the supramolecular assembly prepared in an ice bath as raw material is left-handed. The solvent of the mother liquor of the organic small molecule in the step S21 is p-xylene, and the concentration is one of 22.8 mM, 32.8 mM and 42.8 mM; the solvent of the mother liquor of the achiral fluorescent dye is n-butanol, and the concentration is one of 2.28 mM, 3.28 mM and 4.28 mM; the solvent of the mother liquor of the zinc salt is a mixed solvent of p-xylene and n-butanol, and the concentration is one of 11.4 mM, 16.4 mM and 21.4 mM, the solvent of the mother liquor of the organic high polymer in the step S24 is a mixed solvent of p-xylene and n-butanol, and the concentration is one of 100 mg / mL, 120 mg / mL and 140 mg / mL; the molar ratio of the pyridine vinyl cholesterols to the achiral fluorescent dye is 10:1; and the molar ratio of the pyridine vinyl cholesterols to Zn 2+ is 2:

1.

5. The circularly polarized light emitting polymer film according to claim 4, wherein The organic high polymer is one of polymethyl methacrylate, polyimide resin and polycaprolactone.

6. Application of the supramolecular assembly of any one of claims 1 to 3 or the polymer film of claim 4 or 5 as a circularly polarized luminescent material.

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