Polyimide film with aggregation-induced emission effect and preparation method thereof

Abstract

The invention discloses a polyimide film with an aggregation-induced emission effect and a preparation method thereof, and belongs to the field of flexible electronic luminescence. Through the technical means of side chain grafting, the bonding of TPE fluorophore and PI polymer on the molecular level is realized for the first time, the PI film material is endowed with good photoluminescence performance, and meanwhile, the PI film material has outstanding mechanical strength and thermal stability. In addition, the invention can be expanded to other polymer systems, and is expected to solve the scientific problem that the luminescent property, the thermal property and the mechanical property of the current flexible display luminescent material cannot be considered at the same time. Therefore, according to the technical scheme provided by the invention, diversified design ideas and raw material bases can be provided for molecular structure design and efficient preparation of the PI containing the TPE element and the film material of the PI, and the application of the PI material in the field of flexible electronics can be promoted and deepened.

Description

Technical Field

[0001] The invention belongs to the field of flexible electronic luminescence, and in particular relates to a polyimide film with aggregation-induced luminescence effect and a preparation method thereof. Background Art

[0002] 2019 is the first year of flexible display. Samsung and Huawei successively launched Galaxy Fold and Mate X foldable screen mobile phones, which subverted consumers' perception of traditional mobile phones. Flexible display instantly became a hot spot in the market and the core of future development. Flexible display has greatly expanded the display space form and is also a key technical requirement in emerging display fields such as wearable devices and smartphones. In recent years, new flexible display materials have attracted more and more attention and have developed rapidly. Due to the flexibility and easy processing of polymers, and the fact that thin films can be easily formed through film-forming processes such as spin coating or inkjet printing, the exploration of polymer luminescent materials in the field of flexible display is growing. Conjugated polymers such as poly(p-phenylene)[Burroughes, JH; et al. Nature. 1990, 347.], poly(p-phenylene)[Grem, G.; et al. Synthetic Metals. 1992, 51.] and polythiophene[Perepichka, IF.; et al. Advanced Materials. 2005, 17.] have become important luminescent materials for large-area display devices, commonly known as polymer light-emitting diodes (PLEDs), and have shown great potential in advanced flexible displays. However, the solubility, thermal stability, processability, and photochemical stability of these conjugated luminescent polymers are key issues that restrict their application and development, and these issues need to be urgently addressed.

[0003] Polyimide (PI) has excellent thermal oxidation stability, unique electrical properties, good radiation resistance and solvent resistance, and high mechanical strength, and has attracted considerable attention in different fields (such as aerospace, automotive industry, and optoelectronics). Marston Bogert first reported aromatic PI in 1908. After more than a century of development, the synthesis method and molding process of PI are relatively mature. According to the functionality of the dianhydride and diamine used, researchers have constructed a series of functional PIs of different grades for different applications. However, few studies have applied PI to the field of light emission, such as polymer light-emitting diodes. Traditional PIs have no or only weak photoluminescence (PL) and low fluorescence quantum yield (Φ) due to intermolecular or intramolecular charge transfer (CT) interactions. PL ), making it difficult for PI, an excellent polymer material, to be used as a photofunctional material. Summary of the invention

[0004] Technical issues to be solved:

[0005] In order to avoid the shortcomings of the prior art, the present invention provides a polyimide film with aggregation-induced emission effect and a preparation method thereof. Through the technical means of side-chain grafting, the bonding of TPE fluorophores and PI polymers at the molecular level is realized for the first time, giving the PI film material good photoluminescence properties, while having outstanding mechanical strength and thermal stability. In addition, the present invention can be extended to other polymer systems, and is expected to solve the scientific problem that the current flexible display luminescent materials cannot take into account the luminescence performance, thermal performance, and mechanical properties. Therefore, the technical solution proposed in the present invention can provide a variety of design ideas and raw material bases for the molecular structure design and efficient preparation of PI and its film materials containing TPE elements, which is helpful to promote and deepen the application of PI materials in the field of flexible electronics.

[0006] The technical solution of the present invention is: a polyimide film with aggregation-induced emission effect, wherein the molecular structure of the polyimide film is represented by the following general formula:

[0007]

[0008] Wherein, L is a dibasic acid anhydride residue, and its molar fraction is 50%;

[0009] M is a diamine residue, and its molar fraction is 25% to 40%;

[0010] V is a diamine residue with a hydroxyl group, and its molar fraction is 10% to 25%;

[0011] TPE is a tetraphenyl vinyl element, which is grafted to the side chain of the polymer molecule through an ester group, and its molar fraction is 1 to 2 times that of the diamine V part with a hydroxyl group, that is, p is 1-2.

[0012] A further technical solution of the present invention is that the diamine M is any one or a combination of the following compounds, and its chemical structure is as follows:

[0013]

[0014] A further technical solution of the present invention is: the dibasic acid anhydride L is any one or a combination of the following compounds, and its chemical structure is as follows:

[0015]

[0016] A further technical solution of the present invention is that the diamine V with a hydroxyl group is any one or a combination of the following compounds, and its chemical structure is as follows:

[0017]

[0018] A method for preparing a polyimide film having an aggregation-induced emission effect, the specific steps are as follows:

[0019] Step 1: Add carboxylic acid compound B with TPE moiety and solvent K into a reactor, stir and dissolve, then cool to -10-5°C, add compound W, and continue stirring and reacting for 10-24 hours; concentrate the reaction system, remove solvent K and excess compound W, and obtain compound D;

[0020] The molar ratio of the compound W to the carboxylic acid compound B having a TPE moiety is 1.0 to 3.0:1;

[0021] The mass fraction of the carboxylic acid compound B with TPE moiety in the above reaction system is 2wt% to 8wt%;

[0022] Step 2: using solvent K to dissolve the polyimide polymer T with hydroxyl groups to obtain solution C;

[0023] Step 3: Add compound D, acid binding agent Q and solvent K into the reactor, stir and dissolve, cool to -10-5°C, add solution C, and continue to react at -10-5°C for 2-6h;

[0024] The mass ratio of the compound D to the polymer T is 3 to 6:1;

[0025] Step 4: heating the reaction system of step 3 to reflux, and cooling the reaction solution to 20-35° C. after reflux reaction for 12-24 hours, and pouring the reaction solution into an alcohol solvent S for precipitation to obtain a fibrous polymer; washing the fibrous polymer with the alcohol solvent S for 2-3 times, and then washing the fibrous polymer with distilled water for 2-3 times to obtain a polymer Z; performing Soxhlet extraction on the polymer Z with the alcohol solvent S for 8-24 hours, and finally vacuum drying at 80-160° C. to obtain a polymer E containing a TPE unit;

[0026] Step 5: dissolving polymer E containing TPE unit in solvent K, casting it into a watch glass after dissolution and standing it at 40-80° C. for 10-20 hours to volatilize the solvent, then raising the temperature to 100-180° C., vacuum drying for 2-6 hours, and removing the film after the temperature drops to 20-35° C. to obtain a polyimide film with aggregation-induced emission effect;

[0027] The solid content of the polymer E containing TPE units in the solvent K is 4 wt % to 15 wt %.

[0028] A further technical solution of the present invention is: the preparation method of the carboxylic acid compound B with TPE motif is:

[0029] Step 1: Add bromo-triphenylethylene, 4-(ethoxycarbonyl)phenylboronic acid, basic compound G, catalyst F, toluene, alcohol solvent S and distilled water into a reactor in sequence, and reflux at 80-130° C. for 6-18 hours;

[0030] The molar ratio of the bromo-triphenylethylene to 4-(ethoxycarbonyl)phenylboronic acid is 1:1 to 3.0;

[0031] The molar ratio of the bromo-triphenylethylene to the basic compound G is 1:8-16;

[0032] The molar ratio of the bromo-triphenylethylene to the catalyst F is 1:0.1-0.01;

[0033] The volume ratio of distilled water, toluene and alcohol solvent S is 1:3-6:0.5-2.0;

[0034] The sum of the mass fractions of bromo-triphenylethylene and 4-(ethoxycarbonyl)phenylboronic acid in the reaction system is 3wt% to 10wt%;

[0035] Step 2: After cooling the reaction system of step 1 to 20-35° C., pour it into an aqueous solution of the basic compound G for precipitation, and extract it with dichloromethane 2-3 times, and concentrate the organic phase to obtain a crude product C;

[0036] The mass fraction of the alkaline compound G in the aqueous solution is 5wt% to 30wt%;

[0037] Step 3: Recrystallize the crude product C 2 to 3 times using a mixed solvent of an alcohol solvent S and water to obtain compound A;

[0038] The volume ratio of the alcohol solvent S to water is 4 to 1:1;

[0039] Step 4: Add compound A, alkaline compound H, tetrahydrofuran and distilled water into the reactor in sequence, and reflux at 60-120° C. for 20-30 hours;

[0040] The molar ratio of the basic compound H to the compound A is 2 to 6:1;

[0041] The volume ratio of tetrahydrofuran to distilled water is 0.5 to 2.0:1;

[0042] The mass fraction of compound A in the above reaction system is 2wt% to 10wt%;

[0043] Step 5: Cool the reaction solution obtained in step 4 to 20-35° C., adjust the pH of the reaction system to 1-4 with an acid solution; concentrate to remove tetrahydrofuran, precipitate a white solid, filter, collect the filter cake, wash the filter cake with distilled water 2-3 times, and vacuum dry at 60-120° C. for 6-15 hours to obtain a crude product J;

[0044] Step 6: Recrystallize the crude product J 2-3 times using a mixed solvent of an alcohol solvent S and water to obtain a carboxylic acid compound B with a TPE motif;

[0045] The volume ratio of the alcohol solvent S to water is 4 to 1:1.

[0046] A further technical solution of the present invention is that the compound W is any one of oxalyl chloride, thionyl chloride, phosphorus trichloride, chloride-free phosphorus, thionyl chloride, cyanuric chloride, chloroacetyl chloride, and acetyl chloride, or a combination thereof.

[0047] A further technical solution of the present invention is that the solvent K is any one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, m-cresol, acetonitrile, and dimethyl sulfoxide, or a combination thereof.

[0048] A further technical solution of the present invention is: the preparation method of the polyimide polymer T with hydroxyl group is:

[0049] Step 1: Add diamine M, diamine V with hydroxyl group, dibasic acid anhydride L, and catalyst P into a reactor in sequence, and add solvent U to dissolve the solid, and react at 60-100° C. for 2-8 hours;

[0050] The molar ratio of the dibasic acid anhydride L, the diamine M, and the diamine V having a hydroxyl group is 1:0 to 1:1 to 0;

[0051] The molar ratio of the catalyst P to the dibasic acid anhydride L is 1.0 to 3:1;

[0052] The total mass fraction of the diamine M, the diamine V with hydroxyl groups, and the dibasic acid anhydride L in the above reaction system is 10wt% to 25wt%;

[0053] Step 2: Add catalyst R, heat the reaction system to 180-200°C and continue the reaction for 12-24 hours; cool the reaction system to 20-35°C, slowly precipitate the reaction solution in an alcohol solvent S to obtain a fibrous polymer; wash the polymer with the alcohol solvent S for 2-3 times, and vacuum dry it at 80-140°C for 8-24 hours to obtain a polyimide polymer T with hydroxyl groups.

[0054] A further technical solution of the present invention is that the solvent U is any one of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, m-cresol, and γ-butyrolactone, or a combination thereof.

[0055] Beneficial Effects

[0056] The beneficial effects of the present invention are as follows: the present invention provides a method for preparing a polyimide film material with aggregation-induced emission effect, aiming to utilize the advantages of tetraphenylethylene (TPE) being easy to synthesize, convenient for functionalization, and still having a considerable AIE effect after being modified with different functional groups, and to solve the polyimide Φ at the molecular level by connecting the TPE unit to the polyimide side chain. PL The scientific problem of too low or even no light at all.

[0057] The technical solution proposed in the present invention is completed in three steps, and the product of each step has a precise molecular structure, no raw material waste and high yield, and the overall yield can reach more than 90%. The monomers that can be selected when synthesizing PI have diverse molecular structures, which makes the final PI polymer with hydroxyl groups also diverse in molecular structure. Therefore, PI with AIE effect has greater flexibility and adjustability in molecular structure design, diversified molecular structure, wider application, and the synthesis process is more suitable for mass production. In addition, by regulating the content of hydroxyl groups on the PI molecular chain, the present invention can achieve controllable adjustment of the amount of TPE unit grafting, thereby achieving the final PI material luminescence properties and Φ PL Fine control of.

[0058] The present invention introduces TPE motifs into the PI molecular skeleton to solve the problem of PI non-luminescence. A TPE functional molecule (TPE-COOH) with a carboxyl functional group in the molecular structure is designed and synthesized. Through esterification grafting reaction, the TPE motifs are connected to the PI side chain for the first time, and a series of PI membrane materials with AIE effect are obtained. PL The maximum value can reach 17.6%. By adjusting the flexibility of dianhydride or the grafting amount of TPE fluorophore, the Φ PL Flexible control.

[0059] In addition, the PI film prepared by the present invention also has high mechanical strength (tensile strength>85.0MPa, tensile modulus 2-3GPa), good flexibility (elongation at break>10.0%), outstanding heat resistance (T g >230℃, T d5％ >400℃), which will help promote the widespread application of PI thin film materials in the field of flexible displays. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 Schematic diagram of the synthesis route of TPE-COOH functional molecules;

[0061] Figure 2 Schematic diagram of the synthesis route of polyimide with hydroxyl groups on the side chain;

[0062] Figure 3 Schematic diagram of the synthesis route of photoluminescent polyimide containing TPE motif in the side chain;

[0063] Figure 4 The following are photos of the polyimide with TPE motif in the side chain prepared in Example 8: (a) its appearance under natural light, and (b) its luminescence photo after irradiation with 365nm ultraviolet light in a dark room;

[0064] Figure 5 Thermal performance curves of the photoluminescent polyimide films containing TPE units in the side chains prepared in Example 1, Example 4, Example 5, Example 7, and Example 8: (a) TGA curve, (b) curve of the change of internal friction factor with temperature;

[0065] Figure 6 The tensile stress-strain curves of the photoluminescent polyimide films containing TPE units in the side chains prepared in Example 1, Example 4, Example 5, Example 7 and Example 8;

[0066] Figure 7 Fluorescence excitation spectra and fluorescence emission spectra of the photoluminescent polyimide films containing TPE units in the side chains prepared in Example 2, Example 3, Example 4, Example 6, and Example 8;

[0067] Figure 8 The luminescence of the photoluminescent polyimide containing TPE motifs in the side chain prepared in Example 8 in different solutions: (a) pure DMF solution, (b) a mixed solution of DMF and water (V DMF / V H2O =1:9), (c) a mixed solution of DMF and water (V DMF / V H2O =1:19), the concentration of polymer in the three solutions was c=20 mg / L. DETAILED DESCRIPTION

[0068] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0069] At present, tetraphenylethylene (TPE) is one of the most studied AIE small molecules. It is an efficient fluorophore with aggregation-induced emission characteristics. It can emit blue fluorescence in an aggregated state, and its powder fluorescence quantum yield can reach more than 49%. As a pure hydrocarbon AIE functional molecule, TPE has a simple structure and is easy to functionalize. It is an excellent functional molecule that gives polymers the AIE effect.

[0070] Tetraphenylethylene has many properties:

[0071] (1) TPE is easy to synthesize, and the four benzene rings of TPE are easy to modify;

[0072] (2) After being modified with various functional groups, TPE still has considerable AIE effect;

[0073] (3) TPE elements have excellent stability under most conditions except for some extreme conditions, such as strong ultraviolet rays or high temperatures exceeding 500°C.

[0074] Based on the above problems, the present invention bonds functional molecules with AIE effect to PI at the molecular level to construct a series of PI materials with good luminescent properties, so as to solve the scientific problems of poor thermal stability and insufficient photochemical stability faced by current luminescent polymers, and focus on overcoming the scientific problem of poor luminescent properties of PI materials. Since TPE molecules have good AIE effects and are easy to functionalize, the present invention synthesizes a functional molecule containing a carboxyl functional group (TPE-COOH, with a structural formula such as Figure 1 As shown), and a PI polymer having a hydroxyl group in the molecular side chain is prepared (the polymer chain structure is as shown Figure 2 As shown), the carboxyl group is then chlorinated, and the TPE functional molecule is grafted onto the side chain of the PI molecule for the first time by using the esterification reaction between the acyl chloride and the hydroxyl group (the synthesis process is shown in Figure 3 As shown), the TPE fluorescent group is combined with PI at the molecular level, giving PI an excellent photoluminescence effect.

[0075] The molecular structure of the polyimide film with aggregation-induced emission effect of the present invention has the following general formula:

[0076]

[0077] Wherein, L is a dibasic acid anhydride residue, and its molar fraction is 50%;

[0078] M is a diamine residue, and its molar fraction is 25% to 40%;

[0079] V is a diamine residue with a hydroxyl group, and its molar fraction is 10% to 25%;

[0080] TPE is a tetraphenyl vinyl element, which is grafted to the side chain of the polymer molecule through an ester group, and its molar fraction is 1 to 2 times that of the diamine V part with a hydroxyl group, that is, p is 1-2.

[0081] The diamine M is any one or a combination of the following compounds, and its chemical structural formula is:

[0082]

[0083] The dibasic acid anhydride L is any one or a combination of the following compounds, and its chemical structural formula is:

[0084]

[0085] The diamine V with hydroxyl group is any one or a combination of the following compounds, and its chemical structural formula is:

[0086]

[0087] The present invention provides a method for preparing a polyimide film having an aggregation-induced emission effect, and the specific steps are as follows:

[0088] Step 1: Carboxylic acid compound B with TPE moiety is prepared by the following steps:

[0089] Step 1.1: Add bromo-triphenylethylene, 4-(ethoxycarbonyl)phenylboronic acid, basic compound G, catalyst F, toluene, alcohol solvent S and distilled water in sequence to a single-mouth round-bottom flask equipped with a magnetic rod, and reflux at 80-130° C. for 6-18 hours;

[0090] The molar ratio of the bromo-triphenylethylene to 4-(ethoxycarbonyl)phenylboronic acid is 1:1 to 3.0;

[0091] The molar ratio of the bromo-triphenylethylene to the basic compound G is 1:8-16;

[0092] The molar ratio of the bromo-triphenylethylene to the catalyst F is 1:0.1-0.01;

[0093] The volume ratio of distilled water, toluene and alcohol solvent S is 1:3-6:0.5-2.0;

[0094] The sum of the mass fractions of bromo-triphenylethylene and 4-(ethoxycarbonyl)phenylboronic acid in the reaction system is 3wt% to 10wt%;

[0095] Step 1.2: Cool the reaction system to 20-35° C., pour the reaction solution into an aqueous solution of the basic compound G for precipitation, and extract with dichloromethane 2-3 times, and concentrate the organic phase to obtain a crude product C;

[0096] The mass fraction of the alkaline compound G in the aqueous solution is 5wt% to 30wt%;

[0097] Step 1.3: Recrystallize the crude product C 2 to 3 times using a mixed solvent of an alcohol solvent S and water to obtain compound A;

[0098] The volume ratio of the alcohol solvent S to water is 4 to 1:1;

[0099] Step 1.4: Add compound A, alkaline compound H, tetrahydrofuran and distilled water to a three-necked flask equipped with a condenser in sequence, and reflux at 60-120° C. for 20-30 h;

[0100] The molar ratio of the basic compound H to the compound A is 2 to 6:1;

[0101] The volume ratio of tetrahydrofuran to distilled water is 0.5 to 2.0:1;

[0102] The mass fraction of compound A in the above reaction system is 2wt% to 10wt%;

[0103] Step 1.5: After the reaction is completed, the system is cooled to 20-35°C, and the pH of the reaction system is adjusted to 1-4 with an acid solution; tetrahydrofuran is removed by concentration, a white solid is precipitated, and the filter cake is collected by filtration, and the filter cake is washed with distilled water for 2-3 times, and vacuum dried at 60-120°C for 6-15h to obtain a crude product J;

[0104] Step 1.6: Recrystallize the crude product J 2-3 times using a mixed solvent of an alcohol solvent S and water to obtain a carboxylic acid compound B with a TPE motif;

[0105] The volume ratio of the alcohol solvent S to water is 4 to 1:1;

[0106] Step 2: The polyimide with hydroxyl groups is prepared by the following steps:

[0107] Step 2.1: Add diamine M, diamine V with hydroxyl group, dibasic acid anhydride L, catalyst P in sequence to a three-necked flask equipped with mechanical stirring, and add solvent U to dissolve the solid, and react at 60-100° C. for 2-8 hours;

[0108] The molar ratio of the dibasic acid anhydride L, the diamine M, and the diamine V having a hydroxyl group is 1:0 to 1:1 to 0;

[0109] The molar ratio of the catalyst P to the dibasic acid anhydride L is 1.0 to 3:1;

[0110] The total mass fraction of the diamine M, the diamine V with hydroxyl groups, and the dibasic acid anhydride L in the above reaction system is 10wt% to 25wt%;

[0111] Step 2.2: Add catalyst R, heat the reaction system to 180-200°C and continue the reaction for 12-24 hours; cool the reaction system to 20-35°C, slowly precipitate the reaction solution in an alcohol solvent S to obtain a fibrous polymer; wash the polymer with the alcohol solvent S 2-3 times and vacuum dry it at 80-140°C for 8-24 hours to obtain a polyimide polymer T with hydroxyl groups;

[0112] Step 3: The polyimide film with aggregation-induced emission effect is prepared by the following steps:

[0113] Step 3.1: Add compound B and solvent K to a single-necked flask equipped with a magnetic rod, and stir to dissolve; cool the reaction system to -10 to 5°C, add compound W, and continue to stir and react for 10 to 24 hours; concentrate the reaction system, remove solvent K and excess compound W, and obtain compound D;

[0114] The molar ratio of the compound W to the compound B is 1.0 to 3.0:1;

[0115] The mass fraction of the compound B in the above reaction system is 2wt% to 8wt%;

[0116] Step 3.2: Add compound D, acid-binding agent Q and solvent K to a three-necked flask equipped with a magnetic rod, stir to dissolve, and cool the reaction system; dissolve polymer T with solvent K to obtain solution C; when the system is cooled to -10 to 5°C, add solution C and continue to react at -10 to 5°C for 2 to 6 hours;

[0117] The mass ratio of the compound D to the polymer T is 3 to 6:1;

[0118] Step 3.3: heating the system to reflux, continuing the reaction for 12 to 24 hours, cooling the reaction solution to 20 to 35° C., pouring the reaction solution into an alcohol solvent S for precipitation to obtain a fibrous polymer; washing the polymer with the alcohol solvent S for 2 to 3 times, and then washing the polymer with distilled water for 2 to 3 times to obtain a polymer Z; performing Soxhlet extraction on the polymer Z with the alcohol solvent S for 8 to 24 hours, and finally vacuum drying at 80 to 160° C. to obtain a polymer E containing a TPE unit;

[0119] Step 3.4: dissolving polymer E in solvent K, then casting it into a watch glass and standing it at 40-80°C for 10-20 hours to volatilize the solvent, then raising the temperature to 100-180°C and vacuum drying it for 2-6 hours, and removing the film after the temperature drops to 20-35°C to obtain a polyimide film with aggregation-induced emission effect;

[0120] The solid content of the polymer E in the solvent K is 4 wt % to 15 wt %.

[0121] The alkaline compound G is any one of sodium carbonate, potassium carbonate, cesium carbonate, rubidium carbonate, potassium acetate, and sodium acetate, or a combination thereof; the catalyst F is any one of tetrakis(triphenylphosphine)palladium, di(tri-tert-butylphosphine)palladium, palladium acetate, palladium pivalate, and palladium trifluoroacetate, or a combination thereof; the alkaline compound H is any one of sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, francium hydroxide, strontium hydroxide, barium hydroxide, diammine silver hydroxide, calcium hydroxide, tetrabutylammonium bromide, trioctylmethylammonium chloride, trimethylbenzylammonium chloride, hexadecyltrimethylammonium bromide, triethylbenzylammonium chloride, and 2-hydroxy-N,N,N-trimethylethylamine, or a combination thereof; the catalyst P is any one of glacial acetic acid, benzoic acid, phenylacetic acid, and methylbenzoic acid, or a combination thereof; the catalyst R is isoquinoline, quinoline, pyridine, picoline, any one or a combination of methylquinoline; the alcohol solvent S is any one or a combination of ethanol, methanol, and isopropanol; the solvent K is any one or a combination of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, meta-cresol, acetonitrile, and dimethyl sulfoxide; the acyl chloride compound W is any one or a combination of oxalyl chloride, thionyl chloride, phosphorus trichloride, chloride-free phosphorus, thionyl chloride, cyanuric chloride, chloroacetyl chloride, and acetyl chloride; the acid binding agent Q is any one or a combination of medium pyridine, triethylamine, sodium carbonate, cesium carbonate, potassium carbonate, sodium acetate, N,N-diisopropylethylamine, quinoline, and isoquinoline; the solvent U is any one or a combination of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, meta-cresol, and γ-butyrolactone.

[0122] The above technical solution is further described below in conjunction with embodiments:

[0123] Embodiment 1:

[0124] Bromo-triphenylethylene (1.3410 g, 4.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 5.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (0.2888 g, 0.25 mmol), 100.0 mL toluene, 22.0 mL ethanol and 20.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 130°C for 10 h; the reaction system was cooled to 30°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of ethanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.6168 g, 4.00 mmol), sodium hydroxide (480 mg, 12.00 mmol), 15 mL of tetrahydrofuran and 18 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 hours; the system was cooled to 25°C, and the pH of the reaction system was adjusted to 2 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed with distilled water twice and dried under vacuum at 120°C for 6 hours to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.5058 g, 4.00 mmol, 40 mL tetrahydrofuran to a single-necked flask equipped with a magnetic electron, stir to dissolve; cool the reaction system to 5°C, add oxalyl chloride (0.9519 g, 7.50 mmol), and continue stirring to react for 16 h; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 3°C ​​for later use.To a three-necked flask equipped with a mechanical stirrer, diamine DDS (0.3228 g, 1.30 mmol), diamine APAF with a hydroxyl group (0.2563 g, 0.70 mmol), dibasic acid anhydride BTDA (0.6444 g, 2.00 mmol), benzoic acid (0.7328 g, 6.00 mmol), and 20 mL of m-cresol were added in sequence, and the mixture was reacted at 60 °C for 8 h; 3 drops of isoquinoline were added, and the reaction system was heated to 180 °C for further reaction. The reaction mixture was stirred for 24 hours; the reaction system was cooled to 25°C, and the reaction solution was slowly precipitated in methanol to obtain a fibrous polymer; the polymer was washed with methanol for 3 times and dried under vacuum at 120°C for 12 hours to obtain a polyimide T with hydroxyl groups; TPE-COCl (1.5796 g, 4.00 mmol), triethylamine (0.8095 g, 8.00 mmol), and 40 mL of tetrahydrofuran were added to a three-necked flask equipped with a magnetic electron, stirred to dissolve, and the reaction system was cooled; 90 ml THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to 5°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at 5°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 24 hours, and finally vacuum dried at 100°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMF, and then cast into a watch glass and allowed to stand at 60°C for 20 hours to volatilize the solvent, and then the temperature is raised to 160°C and vacuum dried for 4 hours, and the film is removed after the temperature drops to 25°C to obtain a polyimide film with photoluminescent properties.

[0125] Embodiment 2:

[0126] Bromo-triphenylethylene (1.3410 g, 4.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 5.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (0.2888 g, 0.25 mmol), 100.0 mL toluene, 20.0 mL ethanol and 20.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 110°C for 12 h; the reaction system was cooled to 25°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of methanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.6168 g, 4.00 mmol), sodium hydroxide (480 mg, 12.00 mmol), 25 mL of tetrahydrofuran and 25 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 2 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed with distilled water 3 times and dried in vacuo at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.5058 g, 4.00 mmol) and 40 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 0°C, add oxalyl chloride (1.1423 g, 9.00 mmol), and continue to stir and react for 16 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, add diamine ODA (0.6007 g, 3.00 mmol), diamine APAF with a hydroxyl group (0.3662 g, 1.00 mmol), dibasic acid anhydride 6FDA (1.7770 g, 4.00 mmol), benzoic acid (0.9770 g, 8.00 mmol), and 27 mL of m-cresol in sequence, and react at 80 ° C for 4 h; add 4 drops of isoquinoline, and heat the reaction system to 200 ° C to continue the reaction. 20h; Cool the reaction system to 25°C, slowly precipitate the reaction solution in ethanol to obtain a fibrous polymer; wash the polymer with ethanol three times and vacuum dry at 120°C for 12h to obtain polyimide T with hydroxyl groups; add TPE-COCl (1.5796g, 4.00mmol), triethylamine (1.0119g, 10.00mmol) and 45mL tetrahydrofuran to a three-necked flask equipped with a magnetic electron, stir to dissolve, and cool the reaction system; use 100mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to -5°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at -5°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 16 hours, and finally vacuum dried at 130°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMF, and then cast into a watch glass and allowed to stand at 60°C for 20 hours to volatilize the solvent, and then the temperature is raised to 160°C and vacuum dried for 6 hours, and the film is removed after the temperature drops to 30°C to obtain a polyimide film with photoluminescent properties.

[0127] Embodiment 3:

[0128] Bromo-triphenylethylene (2.0115 g, 6.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 8.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (1.2933 g, 0.25 mmol), 150.0 mL toluene, 35.0 mL ethanol and 35.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 100°C for 12 h; the reaction system was cooled to 25°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of methanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (2.4252 g, 6.00 mmol), sodium hydroxide (800 mg, 20.00 mmol), 40 mL of tetrahydrofuran and 40 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 3 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed with distilled water 3 times and dried in vacuo at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (2.2587 g, 6.00 mmol) and 80 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 0°C, add oxalyl chloride (1.9038 g, 15.00 mmol), and continue to stir and react for 16 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, add diamine ODA (0.6007 g, 2.60 mmol), diamine APAF with a hydroxyl group (0.3662 g, 1.40 mmol), dibasic acid anhydride 6FDA (1.7770 g, 4.00 mmol), benzoic acid (0.9770 g, 8.00 mmol), and 30 mL of m-cresol in sequence, and react at 80 ° C for 4 h; add 4 drops of isoquinoline, and heat the reaction system to 200 ° C to continue the reaction. 20h; Cool the reaction system to 25°C, slowly precipitate the reaction solution in ethanol to obtain a fibrous polymer; wash the polymer with ethanol three times and vacuum dry at 120°C for 12h to obtain polyimide T with hydroxyl groups; add TPE-COCl (2.3694g, 6.00mmol), triethylamine (1.5179g, 15.00mmol) and 75mL tetrahydrofuran to a three-necked flask equipped with a magnet, stir to dissolve, and cool the reaction system; use 100mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to -5°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at -5°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 14 hours, and finally vacuum dried at 130°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMAC, and then cast into a watch glass and allowed to stand at 70°C for 24 hours to volatilize the solvent, and then the temperature is raised to 160°C and vacuum dried for 4 hours, and the film is removed after the temperature drops to 30°C to obtain a polyimide film with photoluminescent properties.

[0129] Embodiment 4:

[0130] Bromo-triphenylethylene (1.3410 g, 4.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 5.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (0.2888 g, 0.25 mmol), 100.0 mL toluene, 20.0 mL ethanol and 20.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 110°C for 12 h; the reaction system was cooled to 25°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of methanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.6168 g, 4.00 mmol), sodium hydroxide (480 mg, 12.00 mmol), 20 mL of tetrahydrofuran and 20 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 3 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed twice with distilled water and dried under vacuum at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.5058 g, 4.00 mmol) and 40 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 5°C, add oxalyl chloride (1.0154 g, 8.00 mmol), and continue to stir and react for 16 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, diamine ODA (0.6007 g, 3.00 mmol), diamine APAF with a hydroxyl group (0.3662 g, 1.00 mmol), dibasic acid anhydride BPADA (2.0820 g, 4.00 mmol), benzoic acid (0.9770 g, 8.00 mmol), and 27 mL of m-cresol were added in sequence and reacted at 80 °C for 4 h; 4 drops of isoquinoline were added, and the reaction system was heated to 200 °C and continued to react. The reaction mixture was stirred for 20 hours; the reaction system was cooled to 25°C, and the reaction solution was slowly precipitated in ethanol to obtain a fibrous polymer; the polymer was washed with ethanol for 3 times and dried in vacuo at 120°C for 12 hours to obtain a polyimide T with hydroxyl groups; TPE-COCl (1.5796 g, 4.00 mmol), triethylamine (0.8095 g, 8.00 mmol), and 40 mL of tetrahydrofuran were added to a three-necked flask equipped with a magnetic particle, stirred to dissolve, and the reaction system was cooled; 110 mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to -5°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at -5°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 12 hours, and finally vacuum dried at 120°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMF, and then cast into a watch glass and allowed to stand at 60°C for 20 hours to volatilize the solvent, and then the temperature is raised to 160°C and vacuum dried for 5 hours, and the film is removed after the temperature drops to 25°C to obtain a polyimide film with photoluminescent properties.

[0131] Embodiment 5:

[0132] Bromo-triphenylethylene (1.5086 g, 4.50 mmol), 4-(ethoxycarbonyl)phenylboric acid (1.1174 g, 5.40 mmol), Na2CO3 (5.2995 g, 50.00 mol), tetrakis(triphenylphosphine)palladium (0.2889 g, 0.25 mmol), 100.0 mL toluene, 25.0 mL ethanol and 25.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 100°C for 18 h; the reaction system was cooled to 30°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of methanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.8189 g, 4.50 mmol), sodium hydroxide (600 mg, 15.00 mmol), 30 mL of tetrahydrofuran and 30 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 100°C for 30 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 2 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed with distilled water 3 times and dried in vacuo at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.6940 g, 4.50 mmol) and 45 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 5°C, add oxalyl chloride (1.2693 g, 10.00 mmol), and continue to stir and react for 18 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, diamine ODA (0.6007 g, 3.00 mmol), diamine BAP with a hydroxyl group (0.2583 g, 1.00 mmol), dibasic acid anhydride BPDA (1.1769 g, 4.00 mmol), benzoic acid (1.0991 g, 9.00 mmol), and 27 mL of m-cresol were added in sequence, and the mixture was reacted at 80 °C for 4 h; 4 drops of isoquinoline were added, and the reaction system was heated to 180 °C and the reaction was continued for 2 h. 4h; cool the reaction system to 25°C, slowly precipitate the reaction solution in methanol to obtain a fibrous polymer; wash the polymer with methanol three times and vacuum dry at 120°C for 16h to obtain polyimide T with hydroxyl groups; add TPE-COCl (1.7771g, 4.50mmol), triethylamine (1.0119g, 10.00mmol) and 60mL tetrahydrofuran to a three-necked flask equipped with a magnetic electron, stir to dissolve, and cool the reaction system; use 150mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to -5°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at -5°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 12 hours, and finally vacuum dried at 120°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMSO, and then cast into a watch glass and allowed to stand at 80°C for 20 hours to volatilize the solvent, and then the temperature is raised to 160°C and vacuum dried for 5 hours, and the film is removed after the temperature drops to 25°C to obtain a polyimide film with photoluminescent properties.

[0133] Embodiment 6:

[0134] Bromo-triphenylethylene (2.0115 g, 6.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 8.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (1.2933 g, 0.25 mmol), 150.0 mL toluene, 35.0 mL ethanol and 35.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 120°C for 12 h; the reaction system was cooled to 30°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of methanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (2.4252 g, 6.00 mmol), sodium hydroxide (800 mg, 20.00 mmol), 40 mL of tetrahydrofuran and 40 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 100°C for 24 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 2 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed with distilled water 3 times and dried in vacuo at 120°C for 16 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 3 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (2.2587 g, 6.00 mmol) and 80 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 0°C, add oxalyl chloride (1.9038 g, 15.00 mmol), and continue to stir and react for 16 h; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, add diamine ODA (0.6007 g, 2.60 mmol), diamine APAF with a hydroxyl group (0.3662 g, 1.40 mmol), dibasic acid anhydride BPADA (2.0820 g, 4.00 mmol), benzoic acid (0.9770 g, 8.00 mmol), and 30 mL of m-cresol in sequence, and react at 80 ° C for 4 h; add 4 drops of isoquinoline, and heat the reaction system to 200 ° C to continue the reaction. 20h; Cool the reaction system to 25°C, slowly precipitate the reaction solution in ethanol to obtain a fibrous polymer; wash the polymer with ethanol three times and vacuum dry it at 100°C for 16h to obtain polyimide T with hydroxyl groups; add TPE-COCl (2.3694g, 6.00mmol), triethylamine (1.5179g, 15.00mmol) and 80mL tetrahydrofuran to a three-necked flask equipped with a magnetic particle, stir to dissolve, and cool the reaction system; use 120mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to 0°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at 0°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 14 hours, and finally vacuum dried at 120°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMAC, and then cast into a watch glass and allowed to stand at 70°C for 24 hours to volatilize the solvent, and then the temperature is raised to 180°C and vacuum dried for 4 hours, and the film is removed after the temperature drops to 30°C to obtain a polyimide film with photoluminescent properties.

[0135] Embodiment 7:

[0136] Bromo-triphenylethylene (1.3410 g, 4.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 5.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (0.2888 g, 0.25 mmol), 80.0 mL toluene, 20.0 mL ethanol and 20.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 110°C for 12 h; the reaction system was cooled to 25°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of ethanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.6168 g, 4.00 mmol), potassium hydroxide (672 mg, 12.00 mmol), 20 mL of tetrahydrofuran and 20 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 h; the system was cooled to 30°C, and the pH of the reaction system was adjusted to 3 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed twice with distilled water and dried under vacuum at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.5058 g, 4.00 mmol) and 40 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 5°C, add oxalyl chloride (1.2693 g, 10.00 mmol), and continue to stir and react for 16 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, diamine BAPP (1.2316 g, 3.00 mmol), diamine BAP with a hydroxyl group (0.2583 g, 1.00 mmol), dibasic acid anhydride BPDA (1.1769 g, 4.00 mmol), benzoic acid (1.0991 g, 9.00 mmol), and 27 mL of m-cresol were added in sequence, and the mixture was reacted at 80 °C for 4 h; 4 drops of isoquinoline were added, and the reaction system was heated to 180 °C to continue the reaction. 24h; Cool the reaction system to 25°C, slowly precipitate the reaction solution in ethanol to obtain a fibrous polymer; wash the polymer with ethanol three times and vacuum dry at 140°C for 10h to obtain polyimide T with hydroxyl groups; add TPE-COCl (1.5796g, 4.00mmol), triethylamine (0.8095g, 8.00mmol) and 45mL tetrahydrofuran to a three-necked flask equipped with a magnet, stir to dissolve, and cool the reaction system; use 150mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to 0°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at 0°C for 4 hours; the system is heated to reflux and the reaction is continued for 14 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 12 hours, and finally vacuum dried at 120°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMF, and then cast into a watch glass and allowed to stand at 70°C for 20 hours to volatilize the solvent, and then the temperature is raised to 180°C and vacuum dried for 5 hours, and the film is removed after the temperature drops to 25°C to obtain a polyimide film with photoluminescent properties.

[0137] Embodiment 8:

[0138] Bromo-triphenylethylene (1.3410 g, 4.00 mmol), 4-(ethoxycarbonyl)phenylboric acid (0.9700 g, 5.00 mmol), Na2CO3 (4.7696 g, 45.00 mol), tetrakis(triphenylphosphine)palladium (0.2888 g, 0.25 mmol), 100.0 mL toluene, 20.0 mL ethanol and 20.0 mL distilled water were added to a single-mouth round-bottom flask equipped with a magnetic electron, and the mixture was refluxed at 110°C for 12 h; the reaction system was cooled to 25°C, the reaction solution was poured into an aqueous solution of sodium bicarbonate for precipitation, and extracted with dichloromethane for 3 times, and the organic phase was concentrated to obtain a crude product; the crude product C was recrystallized using a mixed solvent of ethanol and water 3 times to obtain 4-(1,2,2-triphenylethylene) ethyl benzoate; 4-(1,2,2-triphenylethylene) ethyl benzoate (1.6168 g, 4.00 mmol), sodium hydroxide (480 mg, 12.00 mmol), 20 mL of tetrahydrofuran and 20 mL of distilled water were added to a three-necked flask equipped with a condenser in sequence, and refluxed at 90°C for 24 h; the system was cooled to 25°C, and the pH of the reaction system was adjusted to 3 with an acid solution; tetrahydrofuran was removed by concentration to precipitate a white solid, which was filtered and the filter cake was collected. The filter cake was washed twice with distilled water and dried under vacuum at 120°C for 12 h to obtain a crude product J; the crude product J was recrystallized using a mixed solvent of methanol and water 2 times to obtain the carboxylic acid compound 4-(1,2,2-triphenylethylene)benzoic acid with TPE moiety; add 4-(1,2,2-triphenylethylene)benzoic acid (1.5058 g, 4.00 mmol) and 40 mL of tetrahydrofuran into a single-necked flask equipped with a magnetic electron, and stir to dissolve; cool the reaction system to 5°C, add oxalyl chloride (0.9519 g, 7.50 mmol), and continue to stir and react for 16 hours; concentrate the reaction system to remove tetrahydrofuran and excess oxalyl chloride to obtain TPE-COCl; seal the single-necked flask and refrigerate at 2°C for later use.To a three-necked flask equipped with a mechanical stirrer, diamine ODA (0.2002 g, 1.00 mmol), diamine APAF with a hydroxyl group (0.3662 g, 1.00 mmol), dibasic acid anhydride BPADA (0.8885 g, 2.00 mmol), benzoic acid (0.4885 g, 4.00 mmol), and 11 mL of m-cresol were added in sequence and reacted at 85 °C for 4 h; 3 drops of isoquinoline were added, and the reaction system was heated to 190 °C for further reaction. The reaction mixture was stirred for 18 hours; the reaction system was cooled to 30°C, and the reaction solution was slowly precipitated in ethanol to obtain a fibrous polymer; the polymer was washed with ethanol for 3 times and dried in vacuo at 120°C for 12 hours to obtain a polyimide T with hydroxyl groups; TPE-COCl (1.5796 g, 4.00 mmol), triethylamine (0.8095 g, 8.00 mmol), and 40 mL of tetrahydrofuran were added to a three-necked flask equipped with a magnetic electron, stirred to dissolve, and the reaction system was cooled; 80 mL THF dissolves polyimide T to obtain a tetrahydrofuran solution of polyimide T; when the system is cooled to 0°C, the tetrahydrofuran solution of polyimide T is added and the reaction is continued at 0°C for 4 hours; the system is heated to reflux and the reaction is continued for 16 hours, the reaction solution is cooled to 25°C, and the reaction solution is poured into methanol for precipitation to obtain a fibrous polymer; the polymer is washed with methanol for 3 times, and then with distilled water for 3 times to obtain polymer Z; polymer Z is subjected to Soxhlet extraction with methanol for 16 hours, and finally vacuum dried at 100°C to obtain polymer E containing TPE motifs; the polyimide containing TPE motifs is dissolved in DMAC, and then cast into a watch glass and allowed to stand at 70°C for 16 hours to volatilize the solvent, and then the temperature is raised to 140°C and vacuum dried for 5 hours, and the film is removed after the temperature drops to 25°C to obtain a polyimide film with photoluminescent properties.

[0139] Table 1. Thermal performance data of photoluminescent polyimide films containing TPE motifs in side chains prepared in Example 1, Example 4, Example 5, Example 7, and Example 8

[0140]

[0141] Table 2. Mechanical properties of the photoluminescent polyimide films containing TPE motifs in the side chains prepared in Example 1, Example 4, Example 5, Example 7, and Example 8

[0142]

[0143] Table 3. Maximum excitation wavelength, maximum emission wavelength and fluorescence quantum yield data of the photoluminescent polyimide films containing TPE motifs in the side chains prepared in Example 2, Example 3, Example 4, Example 6 and Example 8

[0144]

[0145] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A polyimide film having aggregation-induced emission effect, characterized in that: The molecular structure of the polyimide film is represented by the following general formula: Wherein, L is a dibasic acid anhydride residue, and its molar fraction is 50%; M is a diamine residue, and its molar fraction is 25% to 40%; V is a diamine residue with a hydroxyl group, and its molar fraction is 10% to 25%; TPE is a tetraphenyl vinyl element, which is grafted to the side chain of the polymer molecule through an ester group, and its molar fraction is 1 to 2 times that of the diamine V part with a hydroxyl group, that is, p is 1-2.

2. A polyimide film having aggregation-induced emission effect according to claim 1, characterized in that: The diamine M is any one or a combination of the following compounds, and its chemical structure is as follows:

3. The polyimide film having aggregation-induced emission effect according to claim 1, characterized in that: The dibasic acid anhydride L is any one or a combination of the following compounds, and its chemical structure is as follows:

4. The polyimide film having aggregation-induced emission effect according to claim 1, characterized in that: The diamine V with hydroxyl group is any one or a combination of the following compounds, and its chemical structure is as follows:

5. A method for preparing a polyimide film having aggregation-induced emission effect according to any one of claims 1 to 4, characterized in that The specific steps are as follows: Step 1: Add carboxylic acid compound B with TPE moiety and solvent K into a reactor, stir and dissolve, then cool to -10-5°C, add compound W, and continue stirring and reacting for 10-24 hours; concentrate the reaction system, remove solvent K and excess compound W, and obtain compound D; The molar ratio of the compound W to the carboxylic acid compound B having a TPE moiety is 1.0 to 3.0:1; The mass fraction of the carboxylic acid compound B with TPE moiety in the above reaction system is 2wt% to 8wt%; Step 2: using solvent K to dissolve the polyimide polymer T with hydroxyl groups to obtain solution C; Step 3: Add compound D, acid-binding agent Q and solvent K into a reactor, stir to dissolve, cool to -10-5°C, add solution C, and continue to react at -10-5°C for 2-6h; The mass ratio of the compound D to the polyimide polymer T having a hydroxyl group is 3 to 6:1; Step 4: heating the reaction system of step 3 to reflux, and cooling the reaction solution to 20-35° C. after reflux reaction for 12-24 hours, and pouring the reaction solution into an alcohol solvent S for precipitation to obtain a fibrous polymer; washing the fibrous polymer with the alcohol solvent S for 2-3 times, and then washing the fibrous polymer with distilled water for 2-3 times to obtain a polymer Z; performing Soxhlet extraction on the polymer Z with the alcohol solvent S for 8-24 hours, and finally vacuum drying at 80-160° C. to obtain a polymer E containing a TPE unit; Step 5: dissolving polymer E containing TPE unit in solvent K, casting it into a watch glass after dissolution and standing it at 40-80° C. for 10-20 hours to volatilize the solvent, then raising the temperature to 100-180° C., vacuum drying for 2-6 hours, and removing the film after the temperature drops to 20-35° C. to obtain a polyimide film with aggregation-induced emission effect; The solid content of the polymer E containing TPE units in the solvent K is 4 wt % to 15 wt %.

6. The method for preparing a polyimide film having aggregation-induced emission effect according to claim 5, characterized in that: The preparation method of the carboxylic acid compound B with TPE motif is: Step 1: Add bromo-triphenylethylene, 4-(ethoxycarbonyl)phenylboronic acid, basic compound G, catalyst F, toluene, alcohol solvent S and distilled water into a reactor in sequence, and reflux at 80-130° C. for 6-18 hours; The molar ratio of the bromo-triphenylethylene to 4-(ethoxycarbonyl)phenylboronic acid is 1:1 to 3.0; The molar ratio of the bromo-triphenylethylene to the basic compound G is 1:8-16; The molar ratio of the bromo-triphenylethylene to the catalyst F is 1:0.1-0.01; The volume ratio of distilled water, toluene and alcohol solvent S is 1:3-6:0.5-2.0; The sum of the mass fractions of bromo-triphenylethylene and 4-(ethoxycarbonyl)phenylboronic acid in the reaction system is 3wt% to 10wt%; Step 2: After cooling the reaction system of step 1 to 20-35° C., pour it into an aqueous solution of the basic compound G for precipitation, and extract it with dichloromethane 2-3 times, and concentrate the organic phase to obtain a crude product C; The mass fraction of the alkaline compound G in the aqueous solution is 5wt% to 30wt%; Step 3: Recrystallize the crude product C 2 to 3 times using a mixed solvent of an alcohol solvent S and water to obtain compound A; The volume ratio of the alcohol solvent S to water is 4 to 1:1; Step 4: Add compound A, alkaline compound H, tetrahydrofuran and distilled water into the reactor in sequence, and reflux at 60-120° C. for 20-30 hours; The molar ratio of the basic compound H to the compound A is 2 to 6:1; The volume ratio of tetrahydrofuran to distilled water is 0.5 to 2.0:1; The mass fraction of compound A in the above reaction system is 2wt% to 10wt%; Step 5: Cool the reaction solution obtained in step 4 to 20-35° C., adjust the pH of the reaction system to 1-4 with an acid solution; concentrate to remove tetrahydrofuran, precipitate a white solid, filter, collect the filter cake, wash the filter cake with distilled water 2-3 times, and vacuum dry at 60-120° C. for 6-15 hours to obtain a crude product J; Step 6: Recrystallize the crude product J 2-3 times using a mixed solvent of an alcohol solvent S and water to obtain a carboxylic acid compound B with a TPE motif; The volume ratio of the alcohol solvent S to water is 4 to 1:

1.

7. The method for preparing a polyimide film having aggregation-induced emission effect according to claim 5, characterized in that: The compound W is any one of oxalyl chloride, thionyl chloride, phosphorus trichloride, phosphorus trichloride, thionyl chloride, cyanuric chloride, chloroacetyl chloride, and acetyl chloride, or a combination thereof.

8. The method for preparing a polyimide film having aggregation-induced emission effect according to claim 5, characterized in that: The solvent K is any one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, m-cresol, acetonitrile and dimethyl sulfoxide, or a combination thereof.

9. The method for preparing a polyimide film having aggregation-induced emission effect according to claim 5, characterized in that: The preparation method of the polyimide polymer T with hydroxyl group is: Step 1: Add diamine M, diamine V with hydroxyl group, dibasic acid anhydride L, and catalyst P into a reactor in sequence, and add solvent U to dissolve the solid, and react at 60-100° C. for 2-8 hours; The molar ratio of the dibasic acid anhydride L, the diamine M, and the diamine V having a hydroxyl group is 1:0 to 1:1 to 0; The molar ratio of the catalyst P to the dibasic acid anhydride L is 1.0 to 3:1; The total mass fraction of the diamine M, the diamine V with hydroxyl groups, and the dibasic acid anhydride L in the above reaction system is 10wt% to 25wt%; Step 2: Add catalyst R, heat the reaction system to 180-200°C and continue the reaction for 12-24 hours; cool the reaction system to 20-35°C, slowly precipitate the reaction solution in an alcohol solvent S to obtain a fibrous polymer; wash the polymer with the alcohol solvent S for 2-3 times, and vacuum dry it at 80-140°C for 8-24 hours to obtain a polyimide polymer T with hydroxyl groups.

10. The method for preparing a polyimide film having aggregation-induced emission effect according to claim 5, characterized in that: The solvent U is any one of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, m-cresol, and γ-butyrolactone, or a combination thereof.

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