Polymer fluorescent agent with super-high photoluminescence property and application thereof

Abstract

The application discloses a high-molecular fluorescent agent with super-high photoluminescence characteristics and application of the high-molecular fluorescent agent in preparation of a polyamide-based fluorescent composite material. The high-molecular fluorescent agent is prepared by using 1,3,6,8-tetrabromopyrene, 1,4-benzene diboronic acid bis(pinacol) ester, 3,6-dibromothiophene [3,2-b] thiophene and tetrakis(triphenylphosphine) palladium as raw materials, the preparation process is simple, the obtained high-molecular fluorescent agent has super-high photoluminescence characteristics, and the preparation of the polyamide-based fluorescent composite material can be realized under the condition of greatly reducing the addition amount of the fluorescent agent; meanwhile, the obtained high-molecular fluorescent agent has a highly conjugated structure, and the obtained polyamide-based fluorescent composite material has good heat resistance, and various health problems (sensitization, carcinogenesis, teratogenesis and the like) caused by the exudation of small-molecule organic dye fluorescent molecules can be avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of fluorescent material preparation, and particularly relates to a high-molecular fluorescent agent with super-high photoluminescence characteristics and application thereof in preparation of a polyamide-based fluorescent composite material. BACKGROUND

[0002] In the textile industry, the main role of the fluorescent agent is fluorescent whitening, which is to convert the invisible ultraviolet radiation absorbed by the product into violet-blue fluorescent radiation, which is complementary to the original yellow radiation to become white light, thereby improving the whiteness of the product under sunlight. The fluorescent agent has been widely used in textiles, papermaking, laundry powder, laundry liquid, soap, rubber, plastic, pigment and paint, etc. In addition, by adding specific fluorescent materials, the fluorescent materials can display specific color light under specific light irradiation, and different color fluorescent fibers can be prepared by composite spinning, which have application value in clothing decoration, warning and safety fields.

[0003] Common fluorescent agents are mostly small-molecule organic dyes, such as pyrazoline type and phthalimide type small-molecule fluorescent agents. The small-molecule fluorescent agent can be absorbed by the human body through the skin, causing a series of health problems. Especially in infant fabric, the exudation of the fluorescent agent can cause immeasurable health hazards to infants. The present application provides a new type of high-molecular fluorescent material, which has high photoluminescence efficiency, and can obtain a polyamide-based composite material with high fluorescent effect under a very small amount of addition, avoiding various health problems (allergy, carcinogenicity, teratogenicity, etc.) caused by the exudation of small-molecule organic dye fluorescent molecules, and the polyamide-based composite material prepared by using the same has important value and broad market application prospect in the field of textiles. SUMMARY

[0004] To solve the series of problems existing in the prior art small-molecule fluorescent agent, the present application provides a new type of high-molecular fluorescent agent, which has very high photoluminescence characteristics, which can impart excellent fluorescent effect to polyamide under a very small amount of addition, thereby obtaining a polyamide-based fluorescent composite material. At the same time, the high-molecular fluorescent agent obtained by the present application has a high conjugated structure, which can impart good heat resistance to the obtained polyamide-based fluorescent composite material.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] A high-molecular fluorescent agent with super-high photoluminescence characteristics, the preparation method thereof comprises the following steps:

[0007] 1) 1,3,6,8-tetrabromopyrene, 1,4-benzenediboronic acid bis(pinacol ester), 3,6-dibromothiophene[3,2-b]thiophene and tetrakis(triphenylphosphine)palladium are added into a mixed solution containing N,N-dimethylformamide and K2CO3;

[0008] 2) After the solution system obtained in step 1) is degassed and purged with nitrogen three times, it is heated and stirred for a period of time;

[0009] 3) After the solution system is cooled to room temperature, it is filtered, then washed with methanol, deionized water, acetone, chloroform and tetrahydrofuran in sequence, and then dried at 70°C to obtain the high-molecular fluorescent agent.

[0010] Further, the molar ratio of total-Br contained in 1,3,6,8-tetrabromopyrene and 3,6-dibromothiophene[3,2-b]thiophene to the borate group contained in 1,4-benzenediboronic acid bis(pinacol ester) in step 1) is 1:1; preferably, the molar ratio of 1,3,6,8-tetrabromopyrene, 3,6-dibromothiophene[3,2-b]thiophene monomers to 1,4-benzenediboronic acid bis(pinacol ester) is 0.9:0.2:2.

[0011] Further, the molar ratio of tetrakis(triphenylphosphine)palladium to 1,4-benzenediboronic acid bis(pinacol ester) used in step 1) is 1:100-1:300.

[0012] Further, the volume ratio of K2CO3 to N,N-dimethylformamide in the mixed solution in step 1) is 1:4-1:5.

[0013] Further, the temperature of the reaction in step 2) is 100-200°C, and the time is 24-72h; preferably, the temperature of the reaction is 150°C, and the time is 48h.

[0014] The high-molecular fluorescent agent with super-high photoluminescence can be used to prepare a polyamide-based fluorescent composite material. The preparation method comprises the following steps:

[0015] 1) Dry polyamide is stirred in formic acid until it is completely dissolved, then the high-molecular fluorescent agent is thoroughly ground and added into the formic acid solution of polyamide, and stirred to uniformly disperse;

[0016] 2) The obtained dispersion is ultrasonically treated, then poured into a culture dish at one time, and heated to slowly evaporate to obtain the polyamide-based fluorescent composite material.

[0017] Further, the amount of the high-molecular fluorescent agent used is 0.1%-5% of the mass of polyamide; preferably, the amount of the high-molecular fluorescent agent used is 0.1%, 0.5% or 1% of the mass of polyamide.

[0018] The significant advantages of the present application are:

[0019] 1. The high molecular fluorescent agent prepared by the present application has high photoluminescence characteristics, and a high fluorescent effect of the polyamide-based composite material can be obtained under the condition of a small amount of addition;

[0020] 2. The high molecular fluorescent agent prepared by the present application has a high degree of conjugated structure, which makes it have good thermal stability, and can avoid various health problems (sensitization, carcinogenesis, teratogenesis, etc.) caused by the exudation of small molecule organic dye fluorescent molecules;

[0021] 3. The polyamide-based fluorescent composite material prepared by using the high molecular fluorescent agent of the present application can be applied to the textile industry, such as the preparation of fluorescent fibers or textile whitening, and has practical value. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The infrared spectrum of the high molecular fluorescent agent prepared for Example 1.

[0023] Figure 2 The thermogravimetric curve of the high molecular fluorescent agent prepared for Example 1.

[0024] Figure 3 The fluorescence spectrum of the high molecular fluorescent agent prepared for Example 1 and the high molecular fluorescent agent / nylon 6 composite material prepared for Example 2 under 365 nm ultraviolet light.

[0025] Figure 4 The fluorescence spectrum of the high molecular fluorescent agent prepared for Example 1 and the high molecular fluorescent agent / nylon 6 composite material prepared for Example 2 under 365 nm ultraviolet light.

[0026] Figure 5 The fluorescence spectrum of the high molecular fluorescent agent prepared for Example 1 and the high molecular fluorescent agent / nylon 6 composite material prepared for Example 2 under 365 nm ultraviolet light. DETAILED DESCRIPTION

[0027] In order to make the content of the present application more convenient to understand, the technical solutions described in the present application will be further described below in combination with specific embodiments, but the present application is not limited thereto.

[0028] Example 1

[0029] A new type of high-molecular fluorescent agent was prepared by Suzuki coupling reaction, i.e. 0.9 mmol of 1,3,6,8-tetrabromopyrene, 2 mmol of 1,4-benzenediboronic acid bis(pinacol ester), 0.2 mmol of 3,6-dibromothiophene[3,2-b]thiophene and 0.01 mmol of tetrakis(triphenylphosphine)palladium were added into a mixed solution consisting of 25 mL of N,N-dimethylformamide and 5 mL of 2M K2CO3 solution, after degassing and purging with nitrogen for three times, the solution was heated to 150°C and stirred for 48 h, after the solution system was cooled to room temperature, the filtrate was washed with methanol, deionized water, acetone, chloroform and tetrahydrofuran in turn, and then dried at 70°C, thus a high-molecular fluorescent agent was obtained.

[0030] Example 2

[0031] The nylon 6 was dried overnight, then 1000 mg of dried nylon 6 was weighed into a beaker, 10 mL of formic acid was added and stirred until completely dissolved, then 5 mg of the high-molecular fluorescent agent prepared in Example 1 was weighed, ground thoroughly and added to the beaker and stirred until uniformly dispersed, after ultrasonic treatment for 30 min, the obtained mixture was cast into a culture dish at one time, and placed on a heating table at 60°C to slowly evaporate the solvent, thus a new type of high-molecular fluorescent agent / nylon 6 composite material containing 0.5 wt% of fluorescent agent was obtained.

[0032] Example 3

[0033] 500 mg of dried nylon 6 was taken, and a new type of high-molecular fluorescent agent / nylon 6 composite material containing 1 wt% of fluorescent agent was prepared according to Example 2.

[0034] Example 4

[0035] 1 mg of the high-molecular fluorescent agent prepared in Example 1 was taken, and a new type of high-molecular fluorescent agent / nylon 6 composite material containing 0.1 wt% of fluorescent agent was prepared according to Example 2.

[0036] Comparative Example

[0037] No high-molecular fluorescent agent was added in the operation, and the other steps were the same as in Example 2.

[0038] Figure 1 The infrared spectrum of the high-molecular fluorescent agent prepared in Example 1 is shown in Figure 1. Figure 1 It can be seen that the characteristic peak at 833 cm -1 corresponds to the in-plane deformation vibration of thiophene ring =H, and the characteristic peaks at 1600 cm -1 and 1359 cm -1 belong to the skeleton vibration of aromatic ring, indicating the successful preparation of the high-molecular fluorescent agent.

[0039] Figure 2Thermogravimetric curve of the polymeric fluorescent agent prepared in Example 1. Figure 2 It can be seen that the main weight loss temperature of the obtained fluorescent agent is above 400℃, and the residual mass after 800℃ is about 65.2%, which shows high thermal stability.

[0040] Figure 3 The fluorescence spectrum of the polymeric fluorescent agent prepared in Example 1 under 365 nm ultraviolet light. Figure 3 It can be seen that it emits a yellow-green fluorescence under ultraviolet light.

[0041] Figure 4 The fluorescence spectra of the polymeric fluorescent agent prepared in Example 1 and the polymeric fluorescent agent / nylon 6 composite material prepared in Example 2 are shown. As can be seen from the figures, the fluorescent agent exhibits a very strong emission peak under 365 nm ultraviolet light irradiation, indicating its extremely high photoluminescence properties. Furthermore, the addition of only 0.5 wt% of the fluorescent agent to nylon 6 results in significant photoluminescence, proving it to be an effective composite method.

[0042] Figure 5 The images show a comparison of the fluorescence of the polymer fluorescent agent / nylon 6 composite materials prepared in Examples 2, 3, and 4 (a, b, c) and the pure nylon 6 prepared in Comparative Example (d) under natural light (left) and 365nm ultraviolet light (right). It is clearly visible from the images that the composite materials prepared with the three different proportions of fluorescent agent doping can all emit blue-green fluorescence, exhibiting high photoluminescence properties; while the pure PA 6 obtained in the Comparative Example does not possess photoluminescence capability.

[0043] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A method for preparing a polymeric fluorescent agent with ultra-high photoluminescence properties, characterized in that, Includes the following steps: 1) Add 1,3,6,8-tetrabromopyrene, 1,4-benzenediboronic acid bis(pinacol) ester, 3,6-dibromothiophene[3,2-b]thiophene and tetra(triphenylphosphine)palladium to a mixed solution containing N,N-dimethylformamide and K2CO3; 2) After degassing the solution system obtained in step 1) and purging it with nitrogen three times, heat and stir the reaction for a period of time; 3) After the solution system is cooled to room temperature, it is filtered, and then washed sequentially with methanol, deionized water, acetone, chloroform and tetrahydrofuran, and dried at 70°C to obtain the polymeric fluorescent agent.

2. The method for preparing the polymeric fluorescent agent according to claim 1, characterized in that, In step 1), the molar ratio of the total -Br in 1,3,6,8-tetrabromopyrene and 3,6-dibromothiophene [3,2-b]thiophene to the borate ester group in 1,4-phenyldiboronic acid bis(pinacol) ester is 1:1; the molar ratio of tetra(triphenylphosphine)palladium to 1,4-phenyldiboronic acid bis(pinacol) ester is 1:100 to 1:

300.

3. The method for preparing the polymeric fluorescent agent according to claim 1, characterized in that, Step 1) The volume ratio of K2CO3 to N,N-dimethylformamide in the mixed solution is 1:4 to 1:

5.

4. The method for preparing the polymeric fluorescent agent according to claim 1, characterized in that, Step 2) The reaction temperature is 100-200℃ and the time is 24-72h.

5. A polymeric fluorescent agent with ultra-high photoluminescence properties prepared by the preparation method described in claim 1.

6. The application of a polymeric fluorescent agent with ultra-high photoluminescence properties as described in claim 5 in the preparation of polyamide-based fluorescent composite materials.

7. The application according to claim 6, characterized in that, Its application method includes the following steps: 1) Stir the dried polyamide in formic acid until fully dissolved, then grind the polymer fluorescent agent thoroughly and add it to the formic acid solution of the polyamide, stirring to disperse it evenly; 2) After sonicating the obtained dispersion, pour it into a petri dish all at once and heat it to slowly evaporate, thus obtaining the polyamide-based fluorescent composite material.

8. The application according to claim 7, characterized in that, The amount of the polymeric fluorescent agent used is 0.1%-5% of the mass of the polyamide.

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