CN110698651B

CN110698651B - Aggregation-induced red-shift luminescent polymer and preparation method and application thereof

Info

Publication number: CN110698651B
Application number: CN201910972263.1A
Authority: CN
Inventors: 余振强; 孟振功; 付阔; 张燕凤
Original assignee: Shenzhen University
Current assignee: Shenzhen University
Priority date: 2019-10-14
Filing date: 2019-10-14
Publication date: 2022-04-01
Anticipated expiration: 2039-10-14
Also published as: CN110698651A

Abstract

The invention discloses an aggregation-induced red-shift luminescent polymer and a preparation method and application thereof, wherein the general structural formula of the aggregation-induced red-shift luminescent polymer is

Wherein n is an integer greater than or equal to 8; r₁、R₂Independently selected from alkyl groups. According to the invention, the AIE element is introduced into the side chain of the polymer by using the short spacer, and the sector alkyl chain is introduced into the side chain, so that the rheological property and the processing property of the polymer are improved, and the obtained AIE material has the property of ultralong red shift; when the side chain regulation strategy of the invention introduces functional groups, the main chain structure is not damaged, and simultaneously, the material can be endowed with more abundant functions.

Description

Aggregation-induced red-shift luminescent polymer and preparation method and application thereof

Technical Field

The invention relates to the technical field of luminescent material preparation, in particular to an aggregation-induced red-shift luminescent polymer and a preparation method and application thereof.

Background

Aggregation-Induced Emission (AIE) refers to a gradual increase in luminescence of a luminescent material with increasing degree of molecular Aggregation, as opposed to traditional Aggregation resulting in quenching. In view of the fact that the fluorescent material is more widely used in the luminescence of the body state, the AIE phenomenon is developed rapidly after being discovered, and through the process of nearly two decades, the fields of development of novel AIE molecules, discussion of luminescence mechanism, application development and the like are greatly improved. However, few AIE materials have been reported that are very long red-shifted (red-shifted distances greater than 100 nm).

The polyarylalkyne compound has unique chemical structure and diversified functions, and can be widely applied to chemical sensing, biological imaging, optical information storage, stimulus-responsive intelligent materials and the like as a fluorescent material. The polymer main chain has continuous pi conjugation, and a main chain conjugation unit is easy to change or a side chain modification group is easy to regulate, so that the function regulation of the material is realized, and particularly the excellent optical performance of the material is realized. The main chain conjugated element usually adopts an aromatic large conjugated structure, so that the rigidity of the polymer is often further increased in the process of regulating and controlling the polymer, and further solution processing is not facilitated.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention aims to provide an aggregation-induced red-shift luminescent polymer, and a preparation method and application thereof, and aims to solve the problems of few existing solution-processable ultra-long red-shift AIE materials.

The technical scheme of the invention is as follows:

an aggregation-induced red-shift luminescent polymer, wherein the structural general formula of the aggregation-induced red-shift luminescent polymer is shown in the specification

Wherein n is an integer greater than or equal to 8; r₁、R₂Independently selected from alkyl groups.

The preparation method of the aggregation-induced red-shift luminescent polymer comprises the following steps of

As shown in the reaction formula (1), the method comprises the following steps: under the inert atmosphere, in the presence of a palladium catalyst, CuI and an acid binding agent, carrying out polymerization reaction on a compound M1 and a compound M2 in an organic solvent to obtain an aggregation-induced red-shift luminescent polymer P1.

Use of an aggregation-induced bathochromic shift luminescent polymer as described above for the preparation of a fluorescent array.

Has the advantages that: according to the invention, the AIE element is introduced into the side chain of the polymer by using the short spacer, and the sector alkyl chain is introduced into the side chain, so that the rheological property and the processing property of the polymer are improved, and the obtained AIE material has the property of ultralong red shift; when the side chain regulation strategy of the invention introduces functional groups, the main chain structure is not damaged, and simultaneously, the material can be endowed with more abundant functions.

Drawings

FIG. 1 shows compound M1 (R) in example 1 of the present invention₁＝C₈H₁₇) Preparation of schemes (1).

FIG. 2 is a preparation scheme of Compound 5 in example 1 of the present invention.

FIG. 3 shows compound M2 (R) in example 1 of the present invention₂＝C₈H₁₇) Preparation of schemes (1).

FIG. 4 shows that in example 1 of the present invention, H is different₂Same concentration of O volume content (10)^-4M) Compound M2 (R)₂＝C₈H₁₇) THF-H of₂Fluorescence emission curves of the O system are compared.

FIG. 5 shows the same concentration (10) in example 1 of the present invention^-4M) Compound M2 (R)₂＝C₈H₁₇) THF-H of₂Fluorescence multiplying factor (I/I) of O system₀) With H₂Graph of the variation of the volume content of O.

FIG. 6 Polymer P1 (R) in inventive example 1₁＝C₈H₁₇，R₂＝C₈H₁₇) 2D-WAXD graph of (A).

FIG. 7 shows a polymer P1 (R) in example 1 of the present invention₁＝C₈H₁₇，R₂＝C₈H₁₇) In the state of solution ((10)^-4M) UV-vis spectrum, fluorescence spectrum and solid state fluorescence spectrum.

FIG. 8 shows that in example 1 of the present invention, H is different₂O volume content of the same concentration of the polymer P1 (R)₁＝C₈H₁₇，R₂＝C₈H₁₇) THF-H of₂Fluorescence emission spectra of O system vs: (a) the fluorescence emission spectrum contrast diagram before normalization, and (b) the fluorescence emission spectrum contrast diagram after normalization.

FIG. 9 shows the polymer P1 (R) prepared by using different templates in example 1 of the present invention₁＝C₈H₁₇，R₂＝C₈H₁₇) SEM images of patterned fluorescent arrays prepared after nanoimprint: (a) the array is a linear grating array, (b) is a columnar array, (c) is a circular hole array, and (d) is a hexagonal star array.

FIG. 10 is a preparation scheme of Compound M3 in comparative example 1 of the present invention.

FIG. 11 shows the solution state ((10) of Polymer P2 in comparative example 1 of the present invention^-4M) UV-vis spectrum, fluorescence spectrum and solid state fluorescence spectrum.

FIG. 12 shows comparative example 1 of the present invention, which contains different H₂THF-H of the O volume content at the same concentration of Polymer P2₂Fluorescence emission spectra of O system vs: (a) the fluorescence emission spectrum contrast diagram before normalization, and (b) the fluorescence emission spectrum contrast diagram after normalization.

Detailed Description

The invention provides an aggregation-induced red-shift luminescent polymer and a preparation method and application thereof, and the invention is further described in detail below in order to make the purpose, technical scheme and effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment of the invention provides an aggregation-induced red-shift luminescent polymer, and the structural general formula of the aggregation-induced red-shift luminescent polymer is shown in the specification

In the embodiment, the AIE element is introduced into a polymer side chain by using a short spacer, and a fan-shaped alkyl chain is introduced into the side chain, so that the rheological property and the processing property of the polymer are improved, and the obtained AIE material has the property of ultralong red shift; the side chain regulation and control strategy of the invention can not damage the main chain structure when introducing the functional group, and can endow the material with more abundant functions.

In one embodiment, in the aggregation-induced bathochromic light-emitting polymer, R₁、R₂Independently selected from linear alkyl with 4-12 carbon atoms. Preferably, R₁、R₂Are all CH₂C₇H₁₅。

The embodiment of the invention also provides a preparation method of the aggregation-induced red-shift luminescent polymer, wherein the reaction formula is

In the embodiment, a polymerization reaction is designed by utilizing a Sonogashira coupling of a p-phenylenediacetylene monomer and a p-diiodobenzene monomer under the action of a palladium catalyst to prepare a polymer of a phenylalkyne alternating main chain; the variety and performance of the AIE material are further expanded through side chain modification, namely the obtained aggregation-induced red-shift luminescent polymer has good solution processability and ultra-long red shift (the red shift distance is more than 100 nm); in addition, the synthesis conditions of the aggregation-induced red-shift luminescent polymer of the embodiment are not harsh, and the synthesis is easy to control and beneficial to expanded production.

In one embodiment, the inert atmosphere may be, but is not limited to, a nitrogen atmosphere or an argon atmosphere.

In one embodiment, the palladium catalyst may be, but is not limited to, tetrakis (triphenylphosphine) palladium and/or bis (triphenylphosphine) palladium dichloride. Preferably, the palladium catalyst is tetrakis (triphenylphosphine) palladium.

In one embodiment, the compound M1, the compound M2, the palladium catalyst, and the CuI are present in a molar ratio of 1: 1:0.01-0.1: 0.01-0.1. Preferably, the molar ratio of the compound M1 to the compound M2 to the palladium catalyst to the CuI is 1:1:0.05: 0.05.

In one embodiment, the acid scavenger may be, but is not limited to, triethylamine and/or diisopropylamine. Preferably, the acid scavenger is triethylamine.

In one embodiment, the organic solvent may be, but is not limited to, chloroform and/or tetrahydrofuran. Preferably, the organic solvent is chloroform.

In one embodiment, the volume ratio of the organic solvent to the acid scavenger is 1: 0.5-1.1. Preferably, the volume ratio of the organic solvent to the acid scavenger is 1: 1.

in one embodiment, the temperature of the polymerization reaction is 60 to 80 ℃ and/or the time of the polymerization reaction is 12 to 72 hours. Preferably, the polymerization conditions are at 70 ℃ for 48 h.

Under the reaction conditions, the compound M1 and the compound M2 can better perform polymerization reaction, and the obtained aggregation-induced red-shift luminescent polymer has good solution processability and ultra-long red shift (the red shift distance is more than 100 nm).

The invention provides an embodiment of the application of the aggregation-induced red-shift luminescent polymer in preparing a fluorescent array.

In one embodiment, the aggregation-induced red-shift luminescent polymer can be used to prepare fluorescent arrays with controlled morphology by solution processing. Preferably, the solution processing is by nanoimprinting.

The present invention will be described in detail with reference to specific examples; it should be noted that the preparation reactions mentioned in the following examples and comparative examples were carried out under an inert atmosphere (nitrogen atmosphere or argon atmosphere).

Example 1

(1) Preparation of Compound M1 (R)₁＝C₈H₁₇) The preparation route is shown in figure 1, and the specific preparation steps comprise:

(1.1) preparation of 1, 4-bis (octyloxy) benzene (1): 1-bromooctane (15.7mL,90mmol), K₂CO₃(16.6g,120mmol) was added to hydroquinone (3.3g, 30mmol) in DMF (N, N-dimethylformamide) and stirred at 80 ℃ overnight, the reaction was monitored by Thin Layer Chromatography (TLC), after completion of the reaction, cooled to room temperature, the solvent was removed, extracted with dichloromethane (3X 50mL), concentrated and isolated by silica gel column Chromatography to give compound 1 as a white solid (8.6g, 86%). The structure identification data is as follows:¹H NMR(CDCl₃,400MHz,δ/ppm):6.82(s,4H),3.90(t,J＝6.0Hz,4H),1.74–1.65(m,4H),1.34–1.27(m,20H),0.89(t,J＝6.6Hz,6H).¹³C NMR(CDCl₃,100MHz,δ/ppm):153.4,115.6,68.9,32.0,29.7,29.6,29.5,26.3,22.8,14.3.

(1.2) preparation of Compound M1 (R)₁＝C₈H₁₇):1, 4-bis (octyloxy) benzene (3.3g,10mmol) was dissolved in 110mL of a mixed solvent (CH) at 80 ℃₃COOH:H₂O:H₂SO₄50:4:1), then KIO is added₃(0.87g,4mmol) and I₂(3.3g,26 mmol); the mixture was stirred for 10h, cooled to room temperature, the precipitate was collected by filtration and taken up with Na₂CO₃Aqueous solution (10 wt%), NaHSO₃(5 wt%) and water wash the precipitate. With n-hexane/CH₂Cl₂(V/V-1/1) as eluent, and purifying the crude product by column chromatography to obtain the product M1 (R)₁＝C₈H₁₇) As a white solid (4.8g, 82% yield). The data for their employment identification are:¹H NMR(CDCl₃,400MHz,δ/ppm):δ7.17(s,2H),3.92(t,J＝6.4Hz,4H),1.79(tt,J＝6.4Hz,J＝6.8Hz,4H),1.49(q,J＝6.8Hz,4H),1.32(m,16H),0.89(t,J＝6.9Hz,6H).¹³C NMR(CDCl₃,100MHz,δ/ppm):152.9,122.8,86.3,70.4,31.8,29.2(2C),29.1,26.0,22.7,14.1.

(2) the preparation method of 2- (4- ((3,4, 5-tri (octyloxy) benzyl) oxy) phenyl) acetonitrile (compound 5) is shown in a figure 2, and the specific preparation steps comprise:

(2.1) preparation of

ethyl

3,4, 5-tris (octyloxy) benzoate (2):

methyl

3,4, 5-trihydroxybenzoate (3.68g, 0.02mol), 1-bromooctane (10.5ml, 0.06mol) and K₂CO₃(16.56g, 0.12mol) was added to a round-bottomed flask containing 100ml of DMF. The mixture was stirred at 75 ℃ for 24 h. The mixture is then poured into 150ml of water and extracted 3 times with ethyl acetate. The combined organic phases were washed with saturated NaCl solution and with anhydrous Na₂SO₄Dried, filtered and concentrated under reduced pressure. The crude product was isolated by silica gel column chromatography using a dichloromethane/n-hexane mixture (v/v-1/4) as eluent to yield 9.37g of a colorless oil (90% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):7.25(s,2H),4.04-4.00(m,6H),3.89(s,3H),1.85–1.71(m,6H),1.51-1.43(m,6H),1.33–1.29(m,24H),0.88(t,J＝6.8Hz,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):153.2,137.4,136.2,105.2,73.4,69.0,68.0,65.5,31.8,31.6,30.3,29.4,25.8,25.6,22.7,22.6,14.1,14.0.

(2.2) preparation of 3,4, 5-tris (octyloxy) benzyl alcohol (3): to a solution of

ethyl

3,4, 5-tris (octyloxy) benzoate (10.5g, 0.02mol) in THF (tetrahydrofuran) was added LiAlH slowly at 0 deg.C₄(1.9g, 0.05 mol). The mixture was stirred at 80 ℃ for 10h, then quenched overnight by the sequential slow addition of isopropanol (3mL), water (10mL) and 30% NaOH (2 mL). The mixture was then extracted three times with ethyl acetate, dried over anhydrous sodium sulfate, and the organic phases were combined. After removal of the solvent from the organic phase under reduced pressure, the product was obtained as a colorless oil (8.4g, 85% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):6.54(s,2H),4.59(d,2H),3.97(t,4H,J＝7.0Hz),3.94(t,2H,J＝6.8Hz),1.84-1.71(m,6H),1.50–1.42(m,6H),1.31–1.28(m,24H),0.88(t,J＝6.8Hz,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):153.2,138.3,132.3,107.0,73.4,69.1,68.0,47.0,31.8,31.6,30.3,29.3,25.8,25.6,22.7,22.6,14.1,14.0.

(2.3) preparation of 5- (chloromethyl) -1,2, 3-tris (octyloxy) benzene (4): compound 3(3,4, 5-tris (octyloxy) benzyl alcohol, 5.4g) was dispersed in 30mL of THF, and SO was slowly added to the above solution₂Cl₂(3.5 mL). The mixture was stirred vigorously at room temperature for 3h, then quenched with water. Extraction with dichloromethane, combined organic phases, dried and solvent removed gave oil 4(5.04g, 90% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):6.57(s,2H),4.61(d,2H),4.00-3.92(m,6H),1.89-1.67(m,6H),1.50–1.42(m,6H),1.40–1.22(m,24H),0.88(t,J＝8Hz,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):153.2,138.4,132.3,107.1,73.4,69.2,46.9,31.9,31.8,30.4,29.6,29.4(2),29.3,26.1(2),22.7,22.7,14.1.

(2.4) preparation of 2- (4- ((3,4, 5-tris (octyloxy) benzyl) oxy)Yl) phenyl) acetonitrile (5): to a solution of compound 4(1.10g, 2.15mmol) and 20mL acetonitrile was added 2- (4-hydroxyphenyl) acetonitrile (0.29g, 2.15mmol) followed by an excess of K₂CO₃(0.89g, 6.45 mmol). Refluxing the mixture for 12h, cooling to room temperature, extracting with dichloromethane for 3 times, and removing the solvent; the crude product was purified by column chromatography to give the title compound 5 as a colorless oil (1.06g, 81% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):7.29(d,J＝5.2Hz,2H),7.00(d,J＝8.4Hz,2H),6.64(s,2H),4.98(s,2H),4.02-4.00(m,6H),3.82(s,2H),1.85-1.80(m,6H),1.53-1.48(m,6H),1.40-1.28(m,24H),0.9(t,J＝6.8Hz,9H)；¹³C NMR(CDCl₃100Hz,. delta./ppm) 158.6,153.3,138.0,131.5,129.1,122.1,118.2,115.5,106.1,73.4,70.5,69.1,53.4,31.8,31.6,30.3,29.4(2),25.8(2),22.7,22.6,14.1(2). Note:¹³the number in parentheses after the peak in the C NMR indicates the number of groups of peaks having the peak, for example: the number 2 in parentheses of "29.4 (2)" indicates that there are 2 groups of peaks of 29.4.

(3) Preparation of Compound M2 (R)₁＝C₈H₁₇) The preparation route is shown in fig. 3, and the preparation steps comprise:

(3.1) preparation of 1, 4-dibromo-2- (bromomethyl) benzene (6): to a solution of 2, 5-dibromotoluene (1mL, 7.26mmol) in chloroform was added N-bromosuccinimide (NBS) (1.422g, 8.00mmol) and benzoyl peroxide (176.8mg, 0.73 mmol). The mixture was stirred at room temperature for 1h, followed by reflux overnight; after the reaction is finished, filtering the mixture, and removing the solvent to obtain a crude product; the crude product was isolated by silica gel column chromatography using n-hexane as eluent to give compound (6) as a white solid (2.10g, 88% yield). The structure identification data is as follows:¹H NMR(CDCl3,400MHz,δ):7.60(d,J＝2.4Hz,1H),7.44(d,J＝8.8Hz,1H),7.30(d,J＝2.4Hz,1H),4.53(s,2H)；¹³C NMR(CDCl3,100MHz,δ):139.0,134.7,134.0,133.1,123.0,121.5,32.2.

(3.2) preparation of 4- ((2, 5-dibromobenzyl) oxy) benzaldehyde (7): to a mixture of Compound 6(1.9g, 5.8mmol) and 20mL of acetone was added 4-hydroxybenzaldehyde (0.85g, 6.96mmol) followed byExcess of K₂CO₃(1.6g, 11.6 mmol). The mixture was refluxed for 12 hours, then cooled to room temperature, the solvent was removed, and the crude product was extracted 3 times with dichloromethane; concentration and column chromatography gave target compound 7 as a white solid (1.72g, 80% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):9.83(s,1H),7.80(d,J＝8.8Hz,2H),7.61(s,1H),7.39(d,J＝8.48Hz,1H),7.27(d,J＝2.44Hz,1H),7.04(d,J＝8.72Hz,2H),5.09(s,2H).

(3.3) preparation of 4- ((2, 5-bis ((trimethylsilyl) ethynyl) benzyl) oxy) benzaldehyde (8): to compound 7(0.74g, 2mmol) in CH₂Cl₂/ET₃To the N (v/v ═ 1/1) solution was added tetrakis (triphenylphosphine) palladium (Pd (PPh)₃)₄50mg), CuI (30 mg). After the solution was stirred at 0 ℃ for 30min, trimethylsilylacetylene (2mL) was added to form a suspension, the suspension was heated to 75 ℃ for 24h, then the mixture was cooled to room temperature, and the solvent was removed, and the mixture was chromatographed on silica gel column using n-hexane/dichloromethane (v/v ═ 3/1) as an eluent to give compound 8(0.63g, 78% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):9.89(s,1H),7.85(d,J＝8.8Hz,2H),7.59(s,1H)；7.44(d,J＝7.88Hz,1H),7.38(dd,J＝7.96Hz,1.6Hz,1H),7.09(d,J＝8.72Hz,2H),5.25(s,2H),0.24(s,9H),0.20(s,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):190.7,163.6,138.1,132.4,132.0,131.9,131.6,131.2,130.6,123.7,121.7,115.2,114.9,104.2,102.3,101.5,96.8,68.0,-0.1,-0.2(2).

(3.4) preparation of Compound M2 (R)₂＝C₈H₁₇): 4- ((2, 5-bis ((trimethylsilyl) ethynyl) benzyl) oxy) benzaldehyde (compound 8, 0.52g, 1.28mmol) and 2- (4- ((3,4, 5-tris (octyloxy) benzyl) oxy) phenyl) acetonitrile (compound 5, 0.78g,1.28mmol) were dissolved in 40mL EtOH (ethanol) and 4mL THF (tetrahydrofuran), then NaOH (0.21g, 5.12mmol) was added under nitrogen and the mixture was stirred at room temperature, protected from light, for 5 h. The precipitate in the reaction solution was filtered, washed with EtOH and dried to obtain Compound M2 (R)₂＝C₈H₁₇) (0.98g, yield 90%). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):7.86(d,J＝8.84Hz,2H),7.68(s,1H),7.59(d,J＝8.8Hz,2H),7.50(d,J＝7.96Hz,1H),7.41(dd,J＝8.88,1.48Hz,1H),7.36(s,1H),6.63(s,2H),5.27(s,2H),4.99(s,2H),4.00-3.94(m,6H),3.46(s,1H),3.19(s,1H),1.84-1.72(m,6H),1.49-1.44(m,6H),1.33-1.29(m,24H),0.89(t,J＝6.76Hz,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):159.9,159.3,153.4,139.8,139.0,138.0,132.7,131.4,131.3,131.0,130.7,129.0,127.5,127.2,123.0,120.7,118.6,115.3,115.2,108.6,106.1,84.5,82.9,80.2,79.4,73.5,70.6,69.1,67.6,32.0,31.9,30.4,29.6,29.4(2),26.2(2),22.8,22.7,14.2.

containing different H₂Compound M2 (R) at the same concentration with O volume content (0%, 20%, 40%, 60%, 80%, 90%, 95%) (R)₂＝C₈H₁₇) THF-H of₂The results of comparing the fluorescence emission (excitation wavelength 340nm) curves of O system (g/mL) are shown in FIG. 4, and the same concentration of compound M2 (R)₂＝C₈H₁₇) THF-H of₂Fluorescence magnification (I/I) of O System (g/mL)₀Wherein I represents compound M2 (R)₂＝C₈H₁₇) At a different H₂Fluorescence intensity at volume content of O, I₀Represents Compound M2 (R)₂＝C₈H₁₇) At H₂Fluorescence intensity at 0% by volume of O) with H₂The relationship between the changes in the O content by volume (0%, 20%, 40%, 60%, 80%, 90%, 95%) is shown in FIG. 5; it is found that the compound M2 (R) increased with the degree of aggregation₂＝C₈H₁₇) The fluorescence of (a) is significantly increased; indicating that Compound M2 (R)₂＝C₈H₁₇) May be an AIE primitive.

(4) Preparation of Polymer P1 (R)₁＝C₈H₁₇，R₂＝C₈H₁₇) See, scheme (1): mixing Compound M1 (R)₁＝C₈H₁₇0.22g, 0.38mmol) and compound M2 (R)₂＝C₈H₁₇0.33g, 0.38mmol) in 30mL of CHCl₃/Et₃N (v/v-1/1) and stirred for 30min, followed by addition of Pd (PPh)₃)₄(10mg) and CuI (5 mg). Mixture ofStirred at 70 ℃ for 48h and the solvent removed in vacuo. With CHCl₃Extracting and purifying with CHCl₃As eluent, the residue was washed with fast neutral Al₂O₃And (4) performing column chromatography filtration, and removing the volatile solvent to obtain a crude product. Redissolving the crude product in a small amount of CHCl₃Precipitating in methanol, and centrifuging; with CHCl₃-repeating the precipitation 3 times in a methanol system; drying under vacuum gave Polymer P1 (R)₁＝C₈H₁₇，R₂＝C₈H₁₇). The identification data of the physicochemical properties are as follows: IR (KBr, cm)^-1):2208(-C≡N),2105(-C≡C-)；¹H NMR(400MHz,CDCl₃,δ):7.87-7.84(m,2H),7.73-7.68(m,1H),7.60-7.54(m,3H),7.46(s,1H),7.37-7.30(m,2H),7.09-6.95(m,6H),6.62(s,2H),4.99-4.97(m,2H),4.04-3.91(m,12H),1.83-1.73(m,10H),1.47-1.42(m,10H),1.38-1.20(m,40H),0.90-0.81(m,15H).GPC(THF):M_w＝29386,M_n＝11838,PDI＝M_w/M_n＝2.48.

(5) Polymer P1 (R)₁＝C₈H₁₇，R₂＝C₈H₁₇) The Two-Dimensional Wide-Angle X-ray Diffraction (2D-WAXD) test results of (2D-Dimensional Wide-Angle X-ray Diffraction) shown in FIG. 6, three pairs of Diffraction rings (corresponding to 2. theta. angles of 1.7, 3.3 and 5.1, respectively) in the equatorial direction in the low-Angle region showed a q-value ratio of 1:2:3, indicating that the polymer P1 is layered in a smectic phase. This molecular packing pattern is closely related to the aggregation-induced bathochromic shift process.

(6) The polymer P1 obtained in this example was tested for its light emitting properties: this sample P1 was dissolved in THF to give a concentration of c ═ 1.0 × 10^-3Mother liquor of M, then diluted to c 1.0 × 10^-5M, adding water to prepare H with water content (volume percentage) of 0%, 20%, 40%, 60%, 80%, 90% and 95% respectively₂O-THF mixed system, test H₂UV-Visible Absorption Spectrum (UV-vis) and fluorescence emission Spectrum (excitation wavelength of 350nm) of P1 in O-THF mixed system. The UV-vis and fluorescence spectra of P1 in solution and in solid state are shown in FIG. 7, where 348nm andthe absorption peak at 412nm was attributed to the side chain and main chain of polymer P1, respectively, and in addition, the solid-state fluorescence emission appeared red-shifted by more than 110nm with respect to the solution state. The red shift mechanism of the compound is realized by researching H with different water contents₂The fluorescence spectrum of P1 in the O-THF mixture was revealed, as shown in FIG. 8(a, b), when the water content fw in the system was<At 60%, the fluorescence intensity decreases sharply with increasing water content and is accompanied by a red shift, the main emission peak of which comes from the polymer backbone; when the water content fw in the system is more than or equal to 60 percent, the fluorescence intensity of P1 does not change greatly along with the increase of the water content, but the emission is obviously transferred from the main chain to the side chain, which indicates that the aggregation-induced red shift of the polymer P1 is caused by the energy transfer between the main chain and the side chain in the stacking mode of polymer molecules.

(7) Nanoimprinting of the polymer P1 prepared in this example: this sample, P1, was dissolved in CHCl₃The concentration of the intermediate is 1.0 multiplied by 10^-3And (3) dropwise adding the mother solution of M onto a silicon wafer (substrate), covering a polymethoxysilane soft template with a characteristic pattern on the silicon wafer, pressurizing for 5min, and taking down the template to obtain the fluorescent array pattern of P1. Polymer P1 (R)₁＝C₈H₁₇，R₂＝C₈H₁₇) SEM test results of various patterned fluorescent arrays prepared after nanoimprint are shown in fig. 9(a-d), in which (a) is a linear grating array, (b) is a columnar array, (c) is a circular hole-shaped array, and (d) is a hexagonal star-shaped array; the polymer P1 can be processed by solution to prepare precise micro/nano fluorescent array with controllable appearance.

Comparative example 1

(1) Compound M3 was prepared according to the route shown in fig. 10, comprising the specific steps of:

(1.1) preparation of ((2-methyl-1, 4-phenylene) bis (acetylene-1, 1-diyl)) bis (trimethylsilane) (9): to 2, 5-dibromotoluene (0.5g, 2mmol) in CH₂Cl₂/Et₃Adding catalyst Pd (PPh) into N (v/v-1/1) solution₃)₄(50mg), CuI (30 mg). Stirring at 0 deg.C for 30min, adding trimethylsilylacetylene (2mL) to form a suspension, heating the suspension to 75 deg.C for 24h, monitoring the reaction by TLC, and reactingAfter completion of the reaction, the reaction mixture was cooled to room temperature. The solvent was removed and the residue was purified by silica gel column chromatography using n-hexane as an eluent to give compound 9(1.78 g, 81% yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):7.35(d,J＝7.92Hz,1H),7.31(s,1H),7.22(d,J＝7.96Hz,1H),2.39(s,3H),0.26(s,9H),0.24(s,9H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):140.5,132.7,131.9,129.0,123.1,122.9,104.8,103.5,100.2,95.7,20.4,-0.0,-0.1.

(1.2) preparation of compound M3: (2-methyl-1, 4-phenylene) bis (acetylene-2, 1-diyl) bis (trimethylsilane) (compound 9, 0.2g, 0.7mmol) was dissolved in 20ml of ethanol, and then excess K was added₂CO₃(0.39g,2.8 mmol). The mixture was stirred at room temperature for 6h, then CH was used₂Cl₂Extracting for 3 times; the organics were combined and the solvent removed in vacuo. The crude product was purified by silica gel column chromatography using n-hexane as eluent to give compound M3 (stoichiometric yield). The structure identification data is as follows:¹H NMR(CDCl₃,400Hz,δ/ppm):7.23(d,J＝7.92Hz,1H),7.16(s,1H),7.09(d,J＝7.72Hz,1H),3.18(s,1H),2.96(s,1H),2.24(s,3H)；¹³C NMR(CDCl₃,100Hz,δ/ppm):140.8,133.0,132.4,129.2,122.6,12.3,83.3,82.8,82.0,78.6,20.4.

(2) preparation of Polymer P2, according to reaction scheme (2)

Replacement of Compound M2 (R) with Compound M3₂＝C₈H₁₇) The remaining preparation steps were the same as for polymer P1 (R) in example 1₁＝C₈H₁₇，R₂＝C₈H₁₇). The obtained identification data of the physicochemical properties of P2 are as follows: IR (KBr, cm)^-1):2108(-C≡C-)；¹H NMR(400MHz,CDCl₃,δ):7.55-7.51(m,1H),7.50-7.44(m,1H),7.42-7.37(m,1H),7.35-7.29(m,1H),7.01-7.00(m,1H),4.84-4.78(m,2H),4.06-3.94(m,4H),2.54-2.52(m,3H),1.94-1.81(m,4H),1.51-1.46(m,4H),1.38-1.24(m,16H),0.90-0.84(m,6H).GPC(THF):M_w＝19229,M_n＝8337,PDI＝M_w/M_n＝2.31.

(3) The polymer P2 obtained in this comparative example was tested for its light emitting properties: polymer P2 was dissolved in THF to give a concentration of c ═ 1.0 × 10^-3Mother liquor of M, then diluted to c 1.0 × 10^-5M, adding water to prepare H with water content (volume percentage) of 0%, 20%, 40%, 60%, 80%, 90% and 95% respectively₂O-THF mixed system, test H₂UV-Visible Absorption Spectrum (UV-vis) and fluorescence emission Spectrum (excitation wavelength of 350nm) of P2 in O-THF mixed system. The UV-vis and fluorescence spectra of P2 in solution and the fluorescence spectra in solid state are shown in FIG. 11, the UV-vis of polymer P2 has only 441nm of strong absorption peak from the main chain, and the solid state fluorescence emission is significantly weaker than that of polymer P1 (red-shifted by 110nm) although it is also red-shifted (95nm) relative to the solution state. The red shift mechanism of the compound is realized by researching H with different water contents₂The fluorescence spectrum of P2 in the O-THF mixed system is revealed, as shown in FIG. 12(a, b), the fluorescence emission peak from the main chain is gradually decreased with the increase of the water content in the system, indicating that the aggregation-induced red shift of the polymer P2 is caused by the aggregation of H between different molecules of the polymer P2, further proving the energy transfer between the main chain and the side chain in the polymer P1.

In conclusion, the invention provides a gathering-induced red-shift luminescent polymer and a preparation method and application thereof, wherein AIE elements are introduced into a polymer side chain by using a short spacer, and a fan-shaped alkyl chain is introduced into the side chain, so that the rheological property and the processing property of the polymer are improved, and the obtained AIE material has ultralong red-shift performance; the side chain regulation and control strategy of the invention can not damage the main chain structure when introducing the functional group, and can endow the material with more abundant functions.

It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.

Claims

1. A kind ofThe aggregation-induced red-shift luminescent polymer is characterized in that the structural general formula of the aggregation-induced red-shift luminescent polymer is shown in the specification

2. The aggregation-induced bathochromic luminescent polymer as defined in claim 1, wherein R is₁、R₂Independently selected from linear alkyl with 4-12 carbon atoms.

3. A process for preparing an aggregation-induced bathochromic luminescent polymer as defined in claim 1 or 2, characterized in that the reaction formula is

4. The production method according to claim 3, wherein the palladium catalyst is tetrakis (triphenylphosphine) palladium and/or bis (triphenylphosphine) palladium dichloride.

5. The preparation method according to claim 3, wherein the molar ratio of the compound M1, the compound M2, the palladium catalyst and the CuI is 1: 1:0.01-0.1: 0.01-0.1.

6. The preparation method according to claim 3, wherein the acid-binding agent is triethylamine and/or diisopropylamine.

7. The method according to claim 3, wherein the organic solvent is chloroform and/or tetrahydrofuran.

8. The preparation method according to claim 3, wherein the volume ratio of the organic solvent to the acid scavenger is 1: 0.5-1.1.

9. The process according to claim 3, wherein the polymerization temperature is 60 to 80 ℃ and/or the polymerization time is 12 to 72 hours.

10. Use of an aggregation-induced bathochromic shift luminescent polymer as defined in claim 1 or 2 for the preparation of a fluorescent array.