Multicolor fluorescent carbon fiber as well as preparation method and application thereof

Abstract

The invention relates to a multicolor fluorescent carbon fiber and a preparation method and application thereof.The preparation method of the multicolor fluorescent carbon fiber comprises the following steps that S1, modified treatment is conducted on calcined halloysite through amino silane, and modified halloysite is obtained; s2, mixing a waste polyester raw material with the modified halloysite, and sintering in an oxygen-free environment to obtain the multicolor fluorescent carbon fiber. The multicolor fluorescent carbon fiber prepared by adopting a specific method has the characteristics of light absorption, light conversion and temperature increasing, emits blue light, red light and green at the same time, and can be used as a luminescent material to be applied to the fields of biomedical imaging and diagnosis, sensors, light conversion films and the like.

Description

Technical Field

[0001] The present application relates to the field of material technology, and in particular to a multicolor fluorescent carbon fiber and a preparation method and application thereof. Background Art

[0002] The core technology of light conversion film is the development of light energy converter (light conversion agent). The key to preparing light conversion film is to make the light conversion film produce blue and red peaks after sunlight passes through to obtain the gain effect of photosynthesis. Whether it can be finally achieved depends on the light conversion agent and its compatibility with the substrate and light energy conversion. Traditional light conversion agents generally use organic fluorescent molecular light conversion agents, inorganic salt light conversion agents, rare earth complexes, etc. However, organic fluorescent molecular light conversion agents are easily decomposed by long-term light exposure, have a short service life, and have a low light conversion rate; inorganic salt light conversion agents can improve the intensity and service life of light conversion, but there are problems such as low light transmittance, fast light conversion attenuation, and poor compatibility with film resins; horticultural greenhouse films made of rare earth complexes have the advantages of long service life and strong stability, and are favored by researchers, but the structures of most rare earth elements and ligand structures are relatively fixed, which limits their absorption of certain specific bands of ultraviolet light, making it difficult for light conversion films to further enhance their absorption of ultraviolet light, and the preparation process of rare earth complex light conversion agents is relatively complex and expensive. More importantly, existing photoconversion agents have biocompatibility and environmental safety issues. The development of safe, non-toxic, efficient, stable and low-cost photoconversion agents is an urgent need currently faced.

[0003] The difficulties of long-term warming are: 1) The current service life of the degradable film is 60-70 days. How to extend the service life to obtain a degradable mulch film with a service life of more than 100 days is a huge challenge; 2) After the film with warming effect is warmed, the aging rate of the film accelerates as the temperature rises. Therefore, it is a huge technical challenge to meet the requirements of warming and long life at the same time.

[0004] In summary, there is an urgent need for a light conversion agent that can achieve long-term warming of the light conversion film. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides a multi-color fluorescent carbon fiber and a preparation method and application thereof to meet the long-term warming requirements of the light conversion film.

[0006] To achieve the above objectives, the scheme of this application is as follows: In a first aspect, the present invention provides a multicolor fluorescent carbon fiber, wherein the multicolor fluorescent carbon fiber is a fibrous amorphous carbon nanomaterial.

[0007] Optionally, the multicolor fluorescent carbon fiber has a diameter of 25-52 nm and a length of 176-365 nm.

[0008] In a second aspect, the present application also provides a method for preparing the multicolor fluorescent carbon fiber as described above, comprising the following steps: S1. Modifying the calcined halloysite by aminosilane to obtain modified halloysite; S2. Mixing the waste polyester raw material with the modified halloysite, and sintering them in an oxygen-free environment to obtain the multi-color fluorescent carbon fiber.

[0009] Optionally, in step S1, the aminosilane is selected from (3-aminopropyl)triethoxysilane.

[0010] Optionally, in step S1, modifying the calcined halloysite with aminosilane comprises: adding the calcined halloysite to an alcohol solution of aminosilane, stirring at 70-90° C. for 12-24 hours, separating, and drying.

[0011] Optionally, in step S1, the material ratio of the calcined halloysite to the aminosilane is 10 g: 5-10 mL.

[0012] Optionally, in step S2, the mass ratio of the waste polyester raw material to the modified halloysite is 100:0.5-10.

[0013] In a third aspect, the present application also provides the use of the multicolor fluorescent carbon fiber as described above or the multicolor fluorescent carbon fiber prepared according to the method as described above in the preparation of a biodegradable film.

[0014] Beneficial effects of the present invention: The multicolor fluorescent carbon fiber prepared by a specific method in the present application makes the film have light conversion properties. The prepared film can emit blue light, green light and red light at the same time, achieving long-term warming while effectively preventing and controlling pests. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The schematic diagram of this application; Figure 2 This is an electron microscope image of the multi-color fluorescent carbon fiber prepared in Example 1; Figure 3 This is a multicolor effect diagram of the multicolor fluorescent carbon fiber prepared in Example 1; Figure 4 This is a diagram showing the test results of the temperature increase characteristics. The infrared temperature increase film is a light conversion film made of multi-color fluorescent carbon fiber in Example 1. Figure 5 The left figure is the result of the life test of the light-converting film made of the multi-color fluorescent carbon fiber in Example 1, and the right figure is the result of the life test of the light-converting film made of the multi-color fluorescent carbon fiber in Example 2. DETAILED DESCRIPTION

[0016] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0017] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0018] like Figure 1 As shown, the principle of this application is: The multicolor fluorescent carbon fiber is used to give the film light-converting properties. The film can emit blue light and red light at the same time. Traditional light-converting films are single-color light-converting films.

[0019] Unlike the existing light conversion agents, the multicolor fluorescent carbon fiber has stable light conversion performance, long life, and low price. Compared with the three existing light conversion agents, the multicolor fluorescent carbon fiber has good biocompatibility, environmental protection and greenness. When used as a ground film, it is safe for the soil and crop environment. Secondly, the current technology generally uses light conversion greenhouse film with polyethylene as the matrix. This type of material is very stable. After being discarded, the greenhouse film is recycled. This application belongs to a fully degradable agricultural light conversion ground film. The fully biodegradable matrix used will age and degrade under the action of light. The light-converting degradable ground film itself will emit light. It is necessary to solve the problems of luminescence and degradation rate regulation at the same time, which is much more difficult than the traditional light conversion film technology. In this application, the light conversion agent is stable, environmentally friendly, safe and non-toxic, and low-priced; it has the effects of light conversion warming, insect prevention, and increased production; and the light conversion performance is stable and long-lasting, and it can emit light stably throughout the entire use cycle.

[0020] In the following description, numerous details are discussed to provide a more thorough explanation of embodiments of the present invention; however, it is apparent to one skilled in the art that embodiments of the present invention may be practiced without these specific details. Example 1

[0021] A method for preparing multicolor fluorescent carbon fiber, the specific steps are as follows: S1. 10 g of calcined halloysite (commercially available) was added to an ethanol solution of APTES (prepared by 8 mL of APTES and 200 mL of anhydrous ethanol), stirred at 80 ° C for 18 h, filtered, and the filtered solid was dried to dryness to obtain modified halloysite; S2. Mixing the waste polyester raw material (specifically, biodegradable agricultural film containing PBAT and PLA) with the modified halloysite in a mass ratio of 100:5, and then placing it in a tubular furnace, sintering it at 800°C for 2h in a nitrogen atmosphere (flow rate of 20mL / min) to obtain multicolor fluorescent carbon fibers; The obtained multi-color fluorescent carbon fiber was scanned by electron microscope, and the results are as follows: Figure 1 shown.

[0022] The multicolor effect of the prepared multicolor fluorescent carbon fiber was verified. The specific steps were as follows: the luminescence characteristics were characterized using a laser confocal microscope. Figure 2 shown.

[0023] The blue and red light properties of the prepared multi-color fluorescent carbon fiber were verified. The specific steps were as follows: the fluorescent carbon fiber was mixed with biodegradable resin and blown into a film material, and the luminescence properties of the film were characterized using a laser confocal microscope. The results are as follows Figure 3 shown.

[0024] Depend on Figure 2 It can be seen that the multicolor fluorescent carbon fiber prepared in this embodiment is in a fiber shape, specifically, a fiber-like amorphous carbon nanomaterial.

[0025] Statistical analysis of the electron microscope images shows that the multicolor fluorescent carbon fibers prepared in this embodiment have a diameter of 25-52 nm, an average diameter of 38 nm, a maximum length of 365.6 nm, a minimum length of 176.5 nm, and an average length of 247.4 nm.

[0026] Depend on Figure 3 It can be seen that the multicolor fluorescent carbon fiber prepared in this embodiment can absorb light with a wavelength of 400-700nm and emit blue, red and green at the same time. Example 2

[0027] A method for preparing multicolor fluorescent carbon fiber, the specific steps are as follows: S1. 10 g of calcined halloysite (commercially available) was added to an ethanol solution of APTES (prepared by 10 mL of APTES and 200 mL of anhydrous ethanol), stirred at 90 ° C for 12 h, filtered, and the filtered solid was dried to dryness to obtain modified halloysite; S2. Waste polyester raw materials (a mixture of PET bottle flakes and PBAT films in a mass ratio of 1:1) were mixed with modified halloysite in a mass ratio of 100:0.5, and then placed in a tubular furnace and sintered at 600°C for 3 hours in a nitrogen atmosphere (flow rate of 50 mL / min) to obtain multi-color fluorescent carbon fibers. Example 3

[0028] A method for preparing multicolor fluorescent carbon fiber, the specific steps are as follows: S1. 10 g of calcined halloysite (commercially available) was added to an ethanol solution of APTES (prepared by 5 mL of APTES and 200 mL of anhydrous ethanol), stirred at 70 ° C for 24 h, filtered, and the filtered solid was dried to dryness to obtain modified halloysite; S2. Waste polyester raw materials (a mixture of PET, PBT and PBAT in a mass ratio of 1:1:1) and modified halloysite in a mass ratio of 100:10 were mixed, then placed in a tubular furnace, and sintered at 1000°C for 1 hour in a nitrogen atmosphere (flow rate of 5 mL / min) to obtain multi-color fluorescent carbon fibers. Example 4

[0029] A method for preparing multicolor fluorescent carbon fiber, the specific steps are as follows: S1. 10 g of calcined halloysite (commercially available) was added to an ethanol solution of APTES (prepared by 6 mL of APTES and 200 mL of anhydrous ethanol), stirred at 75 ° C for 20 h, filtered, and the filtered solid was dried to dryness to obtain modified halloysite; S2. The waste polyester raw material and the modified halloysite were mixed in a mass ratio of 100:8, and then placed in a tubular furnace, sintered at 750°C for 1.5 hours in a nitrogen atmosphere (flow rate of 2 mL / min) to obtain multi-color fluorescent carbon fiber. Performance Testing The multicolor fluorescent carbon fiber of Example 1-2 is made into a light conversion film;

[0030] The temperature increase characteristics of the light-converting film made of the multicolor fluorescent carbon fiber of Example 1 were detected. Specifically, the film was tested using an infrared thermal imager and compared with an ordinary film. The results are as follows: Figure 4 As shown; The life of the multicolor fluorescent carbon fiber prepared in Example 1-2 is detected by conducting an actual application experiment in the field and observing its use time. The results are as follows: Figure 5 shown.

[0031] Depend on Figure 4It can be seen that compared with the common film, the temperature-increasing effect of the light-converting film made of the multicolor fluorescent carbon fiber of Example 1 is significantly improved. This result shows that the multicolor fluorescent carbon fiber of the present invention can improve the temperature-increasing effect of the light-converting film.

[0032] Depend on Figure 5 It can be seen that the life of the fully biodegradable light-conversion film made of the multicolor fluorescent carbon fiber of Example 1-2 is longer. This result shows that the present application improves the life of the film made of the multicolor fluorescent carbon fiber.

[0033] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A multicolor fluorescent carbon fiber, characterized in that: The multicolor fluorescent carbon fiber is a fibrous amorphous carbon nanomaterial.

2. The multicolor fluorescent carbon fiber according to claim 1, characterized in that: The multicolor fluorescent carbon fiber has a diameter of 25-52 nm and a length of 176-365 nm.

3. The method for preparing the multicolor fluorescent carbon fiber according to claim 1 or 2, characterized in that: The following steps are involved: S1. Modifying the calcined halloysite by aminosilane to obtain modified halloysite; S2. Mixing the waste polyester raw material with the modified halloysite, and sintering them in an oxygen-free environment to obtain the multi-color fluorescent carbon fiber.

4. The preparation method according to claim 3, characterized in that: In step S1, the aminosilane is selected from (3-aminopropyl)triethoxysilane.

5. The preparation method according to claim 3, characterized in that: In step S1, the modification treatment of the calcined halloysite with aminosilane includes: adding the calcined halloysite into an alcohol solution of aminosilane, stirring at 70-90° C. for 12-24 hours, separating, and drying.

6. The preparation method according to claim 3, characterized in that: In step S1, the material ratio of the calcined halloysite to the aminosilane is 10 g: 5-10 mL.

7. The preparation method according to claim 3, characterized in that: In step S2, the mass ratio of the waste polyester raw material to the modified halloysite is 100:0.5-10.

8. Use of the multicolor fluorescent carbon fiber according to claim 1 or 2 or the multicolor fluorescent carbon fiber prepared according to the method according to any one of claims 3 to 7 in the preparation of biodegradable films.

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