Fluorine-containing ferroelectric nematic phase liquid crystal molecule and application thereof

Abstract

The invention discloses a fluorine-containing ferroelectric nematic phase liquid crystal molecule and application thereof, relates to the technical field of photoelectric materials, and solves the problem that the application of a traditional liquid crystal material in a photoelectric functional device is restricted due to low dielectric constant. The molecule adopts a unique achiral 'V'-shaped configuration design, takes a benzene ring as a core skeleton, and realizes performance optimization through meta-position connection of differentiated functional side chains. In the molecular structure design, strong electron-withdrawing trifluoromethyl substituents are introduced into the 2 and 4 sites of a benzene ring of a side chain at one end, so that the intermolecular interaction force is enhanced, and the long-range orderliness of the material is maintained; an alkoxy flexible chain structure is adopted at the other end, so that the dissolving property of the material is improved, and the thermal stability is enhanced. Raw materials are easy to obtain, preparation is simple, fluorine-containing ferroelectric liquid crystal molecules are in a nematic phase, the dielectric constant can reach 1.4 * 10 < 4 > (1kHz), and the fluorine-containing ferroelectric liquid crystal has wide ferroelectric nematic phase transition temperature, high polarization intensity and nonlinear optical response and has important application value in the field of photoelectric functional materials.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic materials, and in particular to a fluorine-containing ferroelectric nematic liquid crystal molecule and applications thereof. Background Art

[0002] Liquid crystal materials are a special class of mesomorphic substances that exhibit both liquid fluidity and crystalline anisotropy. While these materials lose their solid-state rigidity in the molten state, their molecules retain their ordered orientation, resulting in unique macroscopic physical properties. Based on the ability of liquid crystal molecules to undergo orientational changes under the influence of an external field, these materials can be used to modulate light fields by controlling their molecular arrangement. These materials have been widely used in fields such as display devices. However, as non-polar fluids, the low dielectric constant of traditional liquid crystal materials has severely limited their application in optoelectronic devices. This technological bottleneck has been overcome with the discovery of ferroelectric liquid crystal materials.

[0003] Ferroelectric liquid crystals are a class of functional liquid crystal materials that exhibit spontaneous polarization. The separation of positive and negative charge centers within their molecular structure creates an intrinsic dipole moment, which generates spontaneous polarization below the Curie temperature. This polarization direction can be reversibly switched by an external electric field. Compared to traditional liquid crystals, ferroelectric liquid crystals offer significant advantages, including fast response speeds (up to microseconds) and high dielectric constants. This has led to significant potential for applications in cutting-edge fields such as electro-optical modulators and non-volatile memory.

[0004] However, the research reports on ferroelectric liquid crystal materials are still relatively limited. The development of new high-performance ferroelectric liquid crystal materials has become an important research direction in the field of optoelectronic functional materials. Summary of the Invention

[0005] In order to solve the problem that the dielectric constant of traditional liquid crystal materials is low, which restricts their application in optoelectronic functional devices, the present invention proposes a fluorine-containing ferroelectric nematic liquid crystal molecule and its application.

[0006] The technical solutions of the present invention are as follows: A fluorine-containing ferroelectric nematic liquid crystal molecule having the following structure: , named ETC-912.

[0007] In addition, the present invention also provides an application of the above-mentioned fluorine-containing ferroelectric nematic liquid crystal molecules in the field of optoelectronic materials.

[0008] Compared with the prior art, the present invention has the following specific beneficial effects: The present invention provides a fluorine-containing ferroelectric nematic liquid crystal material with an innovative molecular structure design, which shows excellent application potential in the field of optoelectronic functional devices. The liquid crystal molecule adopts a unique non-chiral "V" configuration design, with a benzene ring as the core skeleton, and achieves performance optimization by connecting differentiated functional side chains at the meta position. In the molecular structure design, strong electron-withdrawing trifluoromethyl substituents are introduced at the 2nd and 4th positions of the benzene ring of the side chain at one end, which significantly enhances the intermolecular interaction force and effectively maintains the long-range order of the material; the other end adopts an alkoxy flexible chain structure, which not only improves the solubility performance of the material, but also enhances its thermal stability.

[0009] Experimental verification shows that the fluorine-containing ferroelectric liquid crystal material provided by the present invention has excellent comprehensive performance: under 1kHz test conditions, its dielectric constant is as high as 1.4×10 4 , while also exhibiting wide-temperature ferroelectric nematic phase characteristics, high polarization strength, and significant nonlinear optical response characteristics. These outstanding performance indicators make it of great application value in a variety of high-tech fields, including but not limited to optoelectronic functional materials such as high-speed optical communication devices, next-generation liquid crystal display units, and high-efficiency nonlinear optical elements. In particular, the material's high dielectric constant and fast response characteristics provide new material options for the development of high-performance electro-optical modulation devices, while its excellent nonlinear optical performance opens up new avenues for the research and development of nonlinear optical devices such as optical switches and optical limiters. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A preparation roadmap for the fluorine-containing ferroelectric nematic liquid crystal molecules provided by the present invention; Figure 2 is the intermediate 1 described in the embodiment 1 H-NMR spectrum; Figure 3 is the intermediate 1 described in the embodiment 13 C-NMR spectrum; Figure 4 is the intermediate 2 described in the embodiment 1 H-NMR spectrum; Figure 5 is the intermediate 2 described in the embodiment 13 C-NMR spectrum; Figure 6 is the intermediate 3 described in the embodiment 1 H-NMR spectrum; Figure 7 is the intermediate 3 described in the embodiment 13 C-NMR spectrum; Figure 8 is the intermediate 4 described in the embodiment 1 H-NMR spectrum; Figure 9 is the intermediate 4 described in the embodiment 13 C-NMR spectrum; Figure 10 is the intermediate 5 described in the embodiment 1 H-NMR spectrum; Figure 11 is the intermediate 5 described in the embodiment 13 C-NMR spectrum; Figure 12 is the intermediate 6 described in the embodiment 1 H-NMR spectrum; Figure 13 is the intermediate 6 described in the embodiment 13 C-NMR spectrum; Figure 14 is the intermediate 7 described in the embodiment 1 H-NMR spectrum; Figure 15 is the intermediate 7 described in the embodiment 13 C-NMR spectrum; Figure 16 is the fluorine-containing ferroelectric nematic liquid crystal molecule in the embodiment 1 H-NMR spectrum; Figure 17 is the fluorine-containing ferroelectric nematic liquid crystal molecule in the embodiment 13 C-NMR spectrum; Figure 18 The DSC graph of the fluorine-containing ferroelectric nematic liquid crystal molecules prepared in Example; Figure 19 The hysteresis loop of the fluorine-containing ferroelectric nematic liquid crystal molecules prepared in Example at 100°C; Figure 20 SHG signal intensity of the fluorine-containing ferroelectric nematic liquid crystal molecules prepared in the embodiment at different temperature regions; Figure 21 This is a test diagram of the dielectric properties of the fluorine-containing ferroelectric nematic liquid crystal molecules prepared in Example; Figure 22 This is the thermogravimetric analysis diagram of the new fluorine-containing ferroelectric nematic liquid crystal molecules prepared in Example. DETAILED DESCRIPTION

[0011] In order to make the technical solution of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the specification of the present invention. It should be noted that the following embodiments are only used to better understand the technical solution of the present invention and should not be understood as limiting the present invention.

[0012] Example. The synthetic routes of intermediate 1, intermediate 2, intermediate 3, intermediate 4, intermediate 5, intermediate 6, intermediate 7 and novel fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912 are as shown in the attached specification. Figure 1 shown.

[0013] 3,5-Difluorobenzonitrile (raw material 1, CAS: 64248-63-1), 3-bromophenylboronic acid (raw material 4, CAS: 89598-96-9), 3,5-bis(trifluoromethyl)benzoic acid (raw material 5, CAS: 725-89-3), 4-bromo-2,6-difluorophenol (raw material 6, CAS: 104197-13-9), and biphenylboronic acid pinacol ester (raw material 7, CAS: 73183-34-3) were all purchased directly from Shanghai Haohong Biopharmaceutical Technology Co., Ltd. p-Benzoquinone (raw material 2, CAS: 106-51-4) and bromobutane (raw material 3, CAS: 109-65-9) were purchased directly from Sigma-Aldrich (Shanghai) Trading Co., Ltd.

[0014] 1. Synthesis of Intermediate 1: 3,5-Difluorobenzonitrile (10 g, 35.94 mmol, 1 eq) and anhydrous tetrahydrofuran (300 ml) were added to a three-necked flask. Maintaining the system below 0°C, magnesium dichloride (2,2,6,6-tetramethylpiperidinium) lithium salt (11.33 g, 46.73 mmol, 1.3 eq) was added dropwise. After returning the system to room temperature, iodine (10 g, 39.54 mmol, 1.1 eq) was added. The reaction was allowed to react at room temperature for 8 hours. After completion, the reaction was quenched with saturated ammonium chloride and extracted with ethyl acetate. Anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure. The crude product was purified by column chromatography using a 10:1 ratio of n-hexane to ethyl acetate as the eluent to obtain a white solid, Intermediate 1, in an 81% yield. The structural formula is as follows: .

[0015] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 7.76 (m, 2H); Carbon spectrum: 13 C NMR (125 MHz, DMSO) δ 157.25, 157.18, 155.23, 155.17, 118.15,118.12, 117.99, 117.96, 115.94, 115.91, 115.87, 108.17, 108.11, 108.04,94.23, 94.07, 93.91; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C7H2F2IN,264.92; found, 265.88.

[0016] 2. Synthesis of Intermediate 2: Intermediate 1 (7.5 g) was dissolved in dichloromethane (180 mL) in a three-necked flask. The reaction system was maintained at -10°C under an ice bath. Under nitrogen, diisobutylaluminum hydride (30 mL, 1 M in THF) was slowly added dropwise. The system was allowed to react at room temperature for 1 hour before quenching with 6M hydrochloric acid (150 mL). Extraction was performed with dichloromethane, and anhydrous sodium sulfate was added to the organic phase, which was dried, filtered, and the solvent evaporated under reduced pressure. The crude product was purified by column chromatography using a 5:1 ratio of petroleum ether to dichloromethane as the eluent to afford a pale yellow solid, Intermediate 2, in a 68% yield. The structural formula is as follows: .

[0017] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 9.84 (s, 1H), 7.64 (m, 2H); Carbon spectrum: 13 C NMR (125 MHz, DMSO) δ 191.66, 163.85, 163.85, 138.14, 109.43,109.43, 67.89; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C7H3F2IO, 267.92; found, 268.89.

[0018] 3. Synthesis of Intermediate 3: In a three-necked flask, intermediate 3 (5 g, 18.66 mmol, 1 eq), copper acetate monohydrate (268 mg, 1.34 mmol, 0.072 eq), and TBHP (6.73 g, 74.63 mmol, 0.072 eq) were added to dimethyl sulfoxide (60 ml). p-Benzoquinone (3 g, 27.98 mmol, 1.5 eq) was then added and the temperature was raised to 120°C for overnight reaction. After completion of the reaction, the mixture was cooled to room temperature and extracted with water / ethyl acetate. Anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure. The crude product was purified by column chromatography using ethyl acetate:petroleum ether (1:10) as the eluent to obtain a yellow solid, intermediate 3, in a 73% yield. The structural formula is as follows: .

[0019] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 9.56 (s, 1H), 7.97 (m, 2H), 7.17 (m, 2H), 6.78 (m, 2H); Carbon spectrum: 13 C NMR (125 MHz, DMSO) δ 166.65, 166.63, 166.61, 157.25, 157.18,155.23, 155.17, 154.63, 144.56, 124.31, 124.25, 124.18, 122.66, 116.43,115.53, 115.51, 115.37, 115.35, 94.23, 94.07, 93.91; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 13 H7F2IO3, 375.94; found, 376.92.

[0020] 4. Synthesis of Intermediate 4: In a three-necked flask, bromobutane (1.82 g, 13.29 mmol, 1 eq), potassium carbonate (3.67 g, 26.59 mmol, 2 eq), and intermediate 3 (5 g, 13.29 mmol, 1 eq) were added to N,N-dimethylformamide (30 ml) and reacted at 100°C overnight. After completion of the reaction, the mixture was extracted with ethyl acetate and washed three times with water. Anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure to obtain a crude product. Methanol was added to the crude product, and the mixture was stirred at low temperature in an ethanol dry ice bath for 1 hour. The mixture was then filtered and rinsed with a small amount of petroleum ether. The filter cake was a pale yellow solid, intermediate 4, with a yield of 62%. The structural formula is as follows: .

[0021] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 7.30(m, 2H), 7.18 (m, 2H), 6.99 (m,2H), 3.97 (s, 2H), 1.74 (s, 2H), 1.48 (s, 2H), 1.02 (s, 3H); Carbon spectrum: 13C NMR (125 MHz, DMSO) δ 166.65, 166.63, 166.61, 157.25, 157.18, 156.53, 155.23, 155.17, 144.56, 124.31, 124.25, 124.18, 122.49,117.22, 115.53, 115.51, 115.37, 115.35, 94.23, 94.07, 93.91, 67.81, 31.13,19.20, 13.78; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 17 H 15 F2IO3,432.00; found,432.99.

[0022] 5. Synthesis of Intermediate 5: In a three-necked flask, intermediate 4 (3.5 g, 8.1 mmol, 1 eq), 3-bromophenylboronic acid (1.95 g, 9.72 mmol, 1.2 eq), and 2M aqueous sodium carbonate solution (4 eq) were dissolved in dioxane (50 ml). Under nitrogen, tetrakis(triphenylphosphine)palladium (190 mg, 0.02 eq) was added. The reaction was heated to reflux and allowed to react overnight. After the reaction was completed and cooled to room temperature, the mixture was filtered through a pad of celite and the filter cake was rinsed with ethyl acetate. The filtrate was washed three times with water. Anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure. The crude product was added to a 1:1 ratio of petroleum ether and ethyl acetate. The mixture was stirred overnight in an ethanol dry ice bath, then filtered. The filter cake was rinsed with a small amount of petroleum ether. The filter cake, a white solid, was obtained, which was intermediate 5 in a 59% yield. The structural formula is as follows: .

[0023] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 7.62 (dd, 4H), 7.51 (s, 1H), 7.42 (s,1H), 7.18 (m, 2H), 6.94 (m, 2H), 4.00 (s, 2H), 1.78 (s, 2H), 1.52 (s, 2H),1.03 (s, 3H); Carbon spectrum: 13C NMR (125 MHz, DMSO) δ 166.05, 166.03, 166.00, 159.95, 159.89,157.94, 157.87, 156.53, 144.88, 133.46, 133.40, 133.34, 132.82, 130.89,130.87, 130.84, 130.03, 127.03, 126.97, 126.91, 126.63, 126.61, 126.59,123.17, 122.64, 117.52, 117.36, 117.20, 116.86, 113.90, 113.88, 113.74,113.72, 67.81, 31.13, 19.20, 13.78; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 23 H 19 BrF2O3, 460.05; found, 461.02.

[0024] 6. Synthesis of Intermediate 6: In a three-necked flask, 4-bromo-2,6-difluorophenol (5 g, 23.92 mmol, 1 eq), 3,5-bis(trifluoromethylbenzoic acid) (7.41 g, 28.71 mmol, 1.2 eq), and N,N'-dicyclohexylcarbodiimide (DCC, 8.89 g, 43.06 mmol, 0.08 eq) were added to anhydrous dichloromethane (50 mL). The mixture was ice-cooled under nitrogen. 4-Dimethylaminopyridine (DMAP, 0.24 g, 1.91 mmol, 0.08 eq) dissolved in 10 mL of dichloromethane was then added. The mixture was allowed to react on ice for 4 hours before returning to room temperature and reacting overnight. After completion of the reaction, the mixture was poured into a saturated sodium chloride aqueous solution and extracted with dichloromethane. Anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure. The crude product was purified by column chromatography using petroleum ether: dichloromethane (1:5) as the eluent to obtain a white solid, Intermediate 6, in a yield of 76.6%. The structural formula is as follows: .

[0025] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 8.42 (m, 2H), 8.17 (s, 1H), 7.23 (m, 2H).

[0026] Carbon spectrum:13 C NMR (125 MHz, DMSO) δ 164.73, 164.70, 164.66, 154.54, 154.47,152.52, 152.45, 132.98, 132.97, 132.95, 132.72, 132.71, 132.69, 132.47,132.45, 132.42, 132.21, 130.75, 130.72, 130.69, 130.65, 130.53, 130.37,130.34, 130.32, 130.31, 130.28, 130.21, 125.92, 123.78, 123.70, 123.67,123.63, 123.60, 123.57, 121.64, 119.50, 118.25, 118.23, 118.16, 118.09,118.07, 118.03.

[0027] Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 15 H5BrF8O2,447.93; found,448.91.

[0028] VII. Synthesis of Intermediate 7: Intermediate 6 (7 g, 15.59 mmol, 1 eq) was dissolved in ultra-dry tetrahydrofuran (50 ml) in a three-necked flask and cooled to -78°C. 2M n-butyllithium solution (5 ml) was added dropwise over 5 minutes. After stirring for 0.5 hours, pinacol diboronate (4.75 g, 18.7 mmol, 1.2 eq) was added. After returning to room temperature, the reaction was allowed to proceed overnight. After the reaction, 2M HCl was added to adjust the pH to 3-4. The mixture was extracted with ether, and anhydrous sodium sulfate was added to the organic phase. The mixture was dried, filtered, and the solvent evaporated under reduced pressure. A yellow solid, Intermediate 7, was obtained in a 61.2% yield. The structural formula is as follows: .

[0029] NMR characterization results: Proton spectrum: 1 H NMR (500 MHz, DMSO) δ 8.42 (s, 3H), 6.77 (m, 2H), 1.28 (s, 12H); Carbon spectrum: 13C NMR (125 MHz, DMSO) δ 164.73, 164.70, 164.66, 153.76, 153.69,151.74, 151.67, 142.23, 142.17, 142.10, 133.08, 132.92, 132.76, 132.72,132.71, 132.68, 132.45, 130.75, 130.72, 130.69, 130.65, 130.34, 130.33,130.31, 123.78, 123.70, 123.67, 123.63, 123.60, 123.57, 121.64, 119.50,119.37, 119.34, 119.21, 119.18, 84.11, 24.88; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 21 H 17 BF8O4,496.11; found, 497.05.

[0030] 8. Synthesis method of fluorine-containing ferroelectric nematic liquid crystal molecules: In a three-necked flask, Intermediate 7 (2 g, 4.03 mmol, 1 eq), Intermediate 5 (2.05 g, 4.43 mmol, 1.1 eq), and potassium acetate (0.48 g, 4.84 mmol, 1.2 eq) were added to 75 ml of toluene and 15 ml of methanol. Under nitrogen, bistriphenylphosphine palladium dichloride (56.59 g, 80.62 mmol, 0.02 eq) was added. After the addition of the ingredients, the reaction flask was transferred to a preheated oil bath and reacted at 120°C for 4 hours. After the reaction, the reaction system was poured into water and extracted with toluene. The organic phase was washed three times with water, anhydrous sodium sulfate was added to the organic phase, dried, filtered, and the solvent evaporated under reduced pressure. The crude product was purified by column chromatography using ethyl acetate:petroleum ether in a ratio of 1:10 as the eluent to obtain a pale yellow solid, designated ETC-912, in a 46.8% yield. The structural formula is as follows: .

[0031] NMR characterization results: Proton spectrum: 1H NMR (500 MHz, DMSO) δ 8.42 (m, 5H), 7.72 (m, 3H), 7.50 (m,2H), 7.20 (m, 2H), 7.10 (p, 1H), 6.95 (m, 2H), 4.00 (d, 2H), 1.74 (p, 2H),1.53 (h, 2H), 0.98 (t, 3H); Carbon spectrum: 13 C NMR (125 MHz, DMSO) δ 166.05, 166.03, 166.00, 164.73, 164.70,164.66, 159.95, 159.89, 157.94, 157.87, 156.53, 153.61, 153.54, 151.58,151.52, 144.88, 140.02, 139.96, 139.89, 138.25, 138.23, 138.21, 133.48,133.42, 133.35, 132.72, 132.45, 131.13, 130.97, .64, 117.52, 117.36, 117.20, 116.86, 114.06, 114.04,113.90, 114.78, 114.04,113.91, 114.78, 114.86, 114.90, 114.78, 114.86, 114.90, 114.78, 114.86, 114.90, 114.78, 114.86, 114.90, 114.86, 114.90, 114.86, 114.90, 114.86, 114.90, 114.86, 114.90, 114.86, 114.90, 114.86, 114.90, 113.88, 113.74, 113.72, 67.81, 31.13, 19.20, 13.78; Mass spectrometry characterization results: ESI (m / z): [M+H] ＋ Calcd. for C 38 H 24 F 10 O5,750.15;found, 751.12.

[0032] Effect example. (1) Thermodynamic properties test of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912: Differential scanning calorimetry (DSC) was used to test the thermodynamic properties of the new ferroelectric nematic liquid crystal molecules. Figure 18 This figure shows the phase transition process of the novel fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912 at a heating and cooling rate of 10°C / min. The solid line represents the first cooling curve, showing two phase transition peaks: at 170°C, the transition from the nematic phase to the ferroelectric nematic phase; at 75°C, the transition from the ferroelectric nematic phase to the crystalline phase, i.e., crystallization at 75°C. The dashed line represents the heating curve, also showing two phase transition peaks, corresponding to the melting point peak and the clearing point peak.

[0033] (2) Hysteresis loop test of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912: The hysteresis loop is an important basis for proving whether the new ferroelectric nematic liquid crystal molecules have ferroelectric properties. Figure 19 The PE hysteresis loop of the novel fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912 in the ferroelectric nematic phase at 150°C is shown. The saturation polarization value of the novel fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912 reaches 5.4 µC / cm -2 In summary, the parallelogram-shaped hysteresis loop presented by the new ferroelectric nematic liquid crystal molecules is consistent with the properties of general ferroelectric materials, and the saturation polarization value is significant.

[0034] (3) Second harmonic nonlinear optics (SHG) signal measurement: In order to prove the existence of ferroelectric nematic phase, the second harmonic nonlinear optical (SHG) signal of the new ferroelectric nematic phase liquid crystal molecules was measured. The variation of polarization intensity with temperature can be obtained by measuring the intensity change of SHG signal. Figure 20 As shown in the figure, SHG signals were detected in the temperature range (75~170℃) corresponding to the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912, while no SHG signals were detected in the temperature range of the non-ferroelectric nematic phase, proving the existence of the ferroelectric nematic phase.

[0035] (4) Dielectric properties test of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912: The specific method is to take 2 pieces of paper and use a 1cm 2 The new fluorine-containing ferroelectric nematic liquid crystal molecules prepared in the example were heated to the liquid crystal state, sandwiched between corresponding ITO glasses, and connected in series with gold foil. A dielectric measurement unit with an average electrode gap of 2 μm was formed. The node performance of the liquid crystal molecules was tested, and the results are shown in Figure 2. Figure 21 In the temperature range of 0~225℃, the dielectric constant measured at 1kHz can reach as high as 1.4×10 4 .

[0036] (5) Thermogravimetric analysis of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912: Thermogravimetric analysis is used to detect the thermal decomposition temperature of ferroelectric nematic liquid crystal molecules. Figure 22 This is the thermogravimetric analysis diagram of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912. When the mass loss is 5%, the thermal decomposition temperature of the new fluorine-containing ferroelectric nematic liquid crystal molecule ETC-912 is 290℃, indicating that the new ferroelectric nematic liquid crystal molecule has excellent thermal stability.

[0037] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A fluorine-containing ferroelectric nematic liquid crystal molecule, characterized in that: Has the following structure: 。 2. An application of the fluorine-containing ferroelectric nematic liquid crystal molecules as claimed in claim 1 in the field of optoelectronic materials.

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