Liquid crystal compound, composition and high-frequency component with ultra-low dielectric loss

Abstract

The present invention discloses a liquid crystal compound, a composition and a high-frequency component with ultra-low dielectric loss, and the structural formula of the compound is shown in Formula I: wherein R is selected from an alkyl or alkoxy group having 1 to 10 carbon atoms, an alkenyl or alkenyloxy group having 2 to 10 carbon atoms, a fluorinated alkyl group, a fluorinated alkenyl group and a cycloalkyl group or an alkyl group substituted with a cycloalkyl group; X1 to X8 are methyl or hydrogen, and at least two substituents in X1 to X8 are methyl groups; Z1 and Z2 are respectively selected from a single bond, -C≡C-, -CH=CH-, -CF=CF- and -CH2CH2; Ring A is a benzene ring, cyclohexane or cyclohexene, wherein the hydrogen atoms on the benzene ring can also be substituted by methyl or halogen; n=0, 1 or 2. The liquid crystal compound and the composition of the present invention not only have ultra-low dielectric loss and high quality factor, but also have a wide nematic phase temperature range and low viscosity, and are suitable for fields such as filters, phase shifters, phased array radars and 5G communications.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid crystal materials, and specifically relates to a liquid crystal compound, a composition and a high-frequency component with ultra-low dielectric loss, which is mainly suitable for fields such as filters, adjustable frequency selective surfaces, microwave phase shifters, and microwave phased array antennas. Background Art

[0002] Liquid crystal materials have been widely used in optoelectronic display devices, such as various LCD TVs, desktop LCD monitors, mobile display terminals, etc. By taking advantage of the property that the effective dielectric constant of liquid crystal materials changes with the application of an external electric field or magnetic field, new high-frequency (1GHz to 100GHz) components based on liquid crystal materials have been developed, such as microwave phase shifters based on liquid crystal materials.

[0003] In these high-frequency components based on liquid crystal, the dielectric tuning rate of the liquid crystal material determines the tuning ability of the microwave device. For liquid crystal materials, the dielectric tuning rate (τ) is shown in the following formula (1), which is the dielectric anisotropy (Δε) of the liquid crystal material at high frequencies and the dielectric constant (ε ∥ ) determines:

[0004] τ=Δε / ε ∥ Formula (1);

[0005] The dielectric loss of liquid crystal materials is an important factor affecting the insertion loss of their microwave devices. In order to obtain high-performance liquid crystal microwave devices, the dielectric loss of liquid crystal materials must be reduced. For liquid crystal materials, the loss tangent (tanδ) changes with the arrangement of the liquid crystal molecule director, that is, the loss tangent values ​​of the long axis and short axis directions of the liquid crystal molecules are different. When calculating the loss of liquid crystal materials, the maximum loss value, max(tanδ ∥ ,tanδ ⊥ ) is used to measure the dielectric loss parameters of liquid crystal materials.

[0006] In order to evaluate the performance parameters of liquid crystal materials under microwaves, the quality factor (η) parameter is introduced, as shown in the following formula (2):

[0007] η=τ / max(tanδ ∥ ,tanδ ⊥ ) Formula (2);

[0008] For high frequency device applications, the quality factor (η) needs to be as large as possible. This requires the liquid crystal material to have a large dielectric tuning rate (τ), a low dielectric loss tangent (tanδ ∥ ,tanδ ⊥ However, the dielectric loss tangent value (tanδ ∥,tanδ ⊥ ) is large, resulting in large insertion loss of high-frequency components and low device efficiency, which has become a technical bottleneck for the application and industrialization of microwave devices based on liquid crystals. Therefore, it is urgent to solve the problem of reducing the dielectric loss of liquid crystal materials.

[0009] For practical applications, liquid crystal materials need to be optimized and improved in the following aspects.

[0010] (1) To meet the requirements of outdoor harsh environments, liquid crystal materials must have high-definition bright spots, low crystallization temperature, and the fluctuation of high-frequency performance parameters of liquid crystal materials with changes in external ambient temperature must be as small as possible.

[0011] (2) In order to meet the needs of fast response of high-frequency components, liquid crystal materials need to have low rotational viscosity.

[0012] (3) In order to meet the requirements of high-frequency components working under electric field drive, the liquid crystal material is also required to have an appropriate dielectric anisotropy value at low frequencies, such as 1 kHz.

[0013] In the paper titled “Characterisation and Applications of Nematic Liquid Crystals in Microwave Devices” in Molecular Crystals and Liquid Crystals, 2011, 542(1):196 /

[718] -203 /

[725] , the high-frequency performance and applications of commercial high-birefringence liquid crystal materials were reported. Among them, liquid crystal materials containing cyanobiphenyl and cyanoterphenyl, such as E7 and E44, have the disadvantages of low adjustability and large loss at high frequencies.

[0014] In response to the needs of high-frequency applications, patent CN103443245A discloses a liquid crystal medium containing a bis(phenylacetylene) liquid crystal material, such as the structure shown in the following formula:

[0015]

[0016] Although the compound has a relatively high quality factor at high frequencies, it has a relatively low dielectric loss tangent, tanδ at 30 GHz. ⊥ =0.0064; however, its tuning rate is relatively small, τ = 0.242. The dielectric constant of this compound is relatively small at low frequencies, only 0.8.

[0017] Patents CN107955630A and CN105368465A disclose liquid crystal compositions with NCS groups at the molecular ends and fluorine-substituted benzene rings as the molecular skeleton. Although they have a large dielectric constant and tuning rate at high frequencies, the dielectric loss value is large. In the embodiments disclosed therein, the dielectric loss tanδ ⊥ (19GHz) are all above 0.01.

[0018] Patents CN110499163A and US2019292458A1 disclose liquid crystal compositions having NCS groups at the molecular ends and fluorine-substituted benzene rings as the molecular skeleton. In the disclosed embodiments, the dielectric loss tanδ ⊥ (19GHz)≥0.083. Summary of the invention

[0019] In order to overcome the defects or shortcomings in the prior art, the purpose of the present invention is to provide a liquid crystal compound, composition and high-frequency component with ultra-low dielectric loss, wherein the liquid crystal compound has ultra-low dielectric loss at high frequencies, greater dielectric tunability, a wide nematic phase temperature range, lower rotational viscosity and / or a larger dielectric constant at low frequencies.

[0020] In order to achieve the above tasks, the present invention adopts the following technical solutions:

[0021] A liquid crystal compound with ultra-low dielectric loss, the structure of which is shown in general formula I:

[0022]

[0023] wherein R is selected from an alkyl or alkoxy group having 1 to 10 carbon atoms, an alkenyl or alkenyloxy group having 2 to 10 carbon atoms, a fluorinated alkyl group, a fluorinated alkenyl group, and a cycloalkyl group or an alkyl group substituted with a cycloalkyl group;

[0024] X1-X8 are methyl or hydrogen, and at least two substituents among X1-X8 are methyl;

[0025] Z1 and Z2 are independently selected from a single bond, -C≡C-, -CH=CH-, -CF=CF- and -CH2CH2-;

[0026] Ring A is a benzene ring, cyclohexane or cyclohexene, wherein the hydrogen atoms on the benzene ring may be substituted by methyl or halogen;

[0027] n=0, 1 or 2.

[0028] According to the liquid crystal compound of the present invention, the preferred structure is shown in Table 1:

[0029] Table 1

[0030]

[0031]

[0032] The liquid crystal compound described in the present invention introduces two or more methyl substituents in the direction of the short axis of the molecule, and it is found that there is an unexpected effect: compared with the known liquid crystal containing lateral fluorine substituents and one lateral methyl, the dielectric loss value at high frequency is greatly reduced; and it also maintains a large high-frequency dielectric anisotropy, which is very beneficial to the working needs of microwave devices; at the same time, with the number and position of the methyl substituents, it can also play a significant role in regulating the liquid crystal phase region. For example, compared with the known compounds with one lateral methyl or lateral fluorine substitution, two methyl substituents are conducive to obtaining a nematic liquid crystal phase and suppressing the smectic phase region; when the two methyl groups are on different benzene rings, they can play a role in greatly reducing the melting point of the liquid crystal, which is beneficial to improving the low-temperature performance of the liquid crystal composition; when the two methyl groups are located on the same side of the benzene ring connected to the NCS group, such as the 2,3-dimethyl substituted compound, the clearing point is greatly improved compared with the known one methyl substituted compound, and the clearing point of the liquid crystal composition can be adjusted.

[0033] The synthesis of the liquid crystal compound of the present invention can be carried out by using a palladium-catalyzed coupling reaction strategy to establish a basic molecular skeleton, and then obtaining the target product through appropriate functional group transformation. Specifically, for the compound of the present invention with the general structural formula shown in I:

[0034]

[0035] When Z2 = single bond, a palladium-catalyzed Suzuki coupling reaction is used to establish a molecular skeleton by coupling an aromatic boronic acid and a bromo- or iodo-aniline derivative, and then the aniline derivative intermediate is converted into the target isothiocyanate product:

[0036]

[0037] Synthesis route 1;

[0038] When Z2=-C≡C-, a palladium-catalyzed Sonogashira coupling reaction is used to establish a molecular skeleton by coupling an aryl acetylene with a bromo- or iodo-aniline derivative, and then the aniline derivative intermediate is converted into the target isothiocyanate product:

[0039]

[0040] Synthesis route 2;

[0041] When Z2 = -CH = CH-, -CF = CF-, a palladium-catalyzed Heck coupling reaction is used to establish a molecular skeleton by coupling an aromatic vinyl and a brominated or iodinated aniline derivative, and then the aniline derivative intermediate is converted into the target isothiocyanate product:

[0042]

[0043] Synthesis route 3;

[0044] When Z2=-CH2CH2-, the aniline derivative containing acetylene or ethylene bridge can be hydrogenated to saturated ethylene under palladium catalysis, and then the aniline intermediate can be converted into the isothiocyanate target product through the functional group.

[0045]

[0046] Synthetic route 4;

[0047] Another object of the present invention is to provide a liquid crystal composition with ultra-low dielectric loss, comprising one or more compounds represented by structural formula I.

[0048] The liquid crystal composition of the present invention may further comprise one or more compounds selected from the group consisting of compounds represented by the general structural formula II as a second component:

[0049]

[0050] Wherein R1 and R2 are alkyl groups with 1 to 10 carbon atoms, alkenyl groups with 2 to 10 carbon atoms, fluorinated alkyl groups, fluorinated alkenyl groups, cycloalkyl groups, halogen groups, or NCS groups; Ring A and Ring B are benzene rings, cyclohexane, or cyclohexene, wherein the hydrogen atoms on the benzene rings may be replaced by fluorine atoms;

[0051] and comprising one or more compounds selected from the group consisting of the general structural formula III as the third component:

[0052]

[0053] wherein R1 is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a fluorinated alkyl group, or a fluorinated alkenyl group; 13 is H, methyl, ethyl, and wherein X9~X 13 One of them is methyl or ethyl; k, m and n are 0 or 1 respectively; Ring A is benzene ring, cyclohexane or cyclohexene;

[0054] and comprising one or more compounds selected from the group consisting of the general structural formula IV as the fourth component:

[0055]

[0056] wherein R1 is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a fluorinated alkyl group, or a fluorinated alkenyl group; 14 ~X 17 is H, methyl, ethyl, and X 14 ~X 17One of them is methyl or ethyl, and the rest are H.

[0057] In the composition of the present invention, the compound of the general formula I is further preferably a structure shown in Table 2:

[0058] Table 2

[0059]

[0060]

[0061]

[0062]

[0063] Compared with the currently disclosed high-frequency liquid crystal compositions based on isothiocyanate, the compound of the structural formula I of the present invention is characterized in that there is no lateral fluorine atom substituent in the molecule, and a large and non-polar methyl group is used as a lateral substituent; after introducing two lateral methyl substituents into the molecule, the dielectric loss value of the liquid crystal material at high frequency is greatly reduced.

[0064] The components of the general structural formula II in the composition of the present invention, preferably the specific compound structure is as follows:

[0065]

[0066] The molecular structure of the general structural formula II of the present invention is composed of two rings and has the characteristics of low viscosity, low melting point and low dielectric loss. It can further improve the low-temperature compatibility of the liquid crystal composition, greatly reduce the viscosity of the liquid crystal composition, and reduce the dielectric loss at the same time.

[0067] The general structural formula II-A of the present invention is more preferably the following specific compounds:

[0068]

[0069] Among them, II-B further prefers the following structural compounds:

[0070]

[0071] Among them, II-C further prefers the following structural compounds:

[0072]

[0073] The compound of the general structural formula III in the composition of the present invention has the following preferred specific compound structure:

[0074]

[0075] The compound of the general structural formula III in the composition of the present invention has a wider liquid crystal phase range, lower viscosity, and a larger dielectric constant, and can play a role in adjusting the liquid crystal phase range and the dielectric constant of the composition at low frequencies.

[0076] The compound of the general structural formula IV in the composition of the present invention, preferably the specific compound structure is as follows:

[0077]

[0078] The compound of the general structural formula IV in the composition of the present invention has a wider liquid crystal phase range, a high birefringence, and a large dielectric constant, and can play a role in adjusting the liquid crystal phase range and the dielectric constant of the composition at low frequencies.

[0079] In a preferred embodiment of the present invention, the liquid crystal composition comprises one or more compounds selected from the general formula (I), one or more compounds selected from the general formula (II). In another preferred embodiment of the present invention, the liquid crystal composition comprises one or more compounds of the general formula (I), one or more compounds of the general formula (II) and one or more compounds of the general formula (III). In another preferred embodiment of the present invention, the liquid crystal composition comprises one or more compounds of the general formula (I), one or more compounds of the general formula (II) and one or more compounds of the general formula (III) and one or more compounds of the general formula IV.

[0080] The liquid crystal composition according to the present invention comprises 1% to 100%, preferably 10% to 90%, and more preferably 20% to 80% of the compound of formula I, based on the total amount of the mixture. The liquid crystal composition of the present invention may also comprise 0% to 40%, preferably 5% to 30%, and particularly preferably 10% to 20% of the compound of formula II, based on the total amount of the mixture. The liquid crystal composition of the present invention may also comprise 0% to 90%, preferably 10% to 80%, and particularly preferably 20% to 70% of the compound of formula III, based on the total amount of the mixture. The liquid crystal composition of the present invention may also comprise 0% to 50%, preferably 10% to 40%, and particularly preferably 15% to 30% of the compound of formula IV, based on the total amount of the mixture.

[0081] The liquid crystal composition according to the present invention may further contain 0.001% to 1% of additives, such as hindered phenol antioxidants, amine light stabilizers, etc. wherein the hindered phenol antioxidant is preferably selected from the following structures:

[0082]

[0083] Wherein R is an alkyl group or alkoxy group having 1 to 9 carbon atoms.

[0084] The hindered amine light stabilizer is preferably selected from the following structures:

[0085]

[0086] The preferred amount of hindered phenol antioxidants and amine light stabilizers added is 0.01% to 0.5%, more preferably 0.02% to 0.2%.

[0087] The liquid crystal composition of the present invention may further comprise one or more chiral additives, the content of which is 0.01% to 1%, preferably 0.1% to 0.5%. The chiral additives are preferably selected from the following structures:

[0088]

[0089] wherein it is an alkyl group or an alkoxy group having 1 to 9 carbon atoms.

[0090] The liquid crystal composition according to the present invention is composed of a plurality of compounds, preferably 3 to 20 compounds, more preferably 5 to 18 compounds. These compounds can be mixed in a conventional manner: various compounds are weighed according to a predetermined mass ratio, and then heated, and mixed homogeneously by stirring methods such as magnetic stirring or ultrasound until each component is completely dissolved; and then filtered to obtain. The liquid crystal composition can also be prepared in other conventional ways, such as using a so-called premix, or using a so-called "multi-bottle" system, the components of which are themselves ready-to-use mixtures.

[0091] The performance of liquid crystal at high frequencies was tested using the test method reported in the literature: Penirschke, A. (2004). Cavityperturbation method for characterization of liquid crystals up to 35 GHz. Microwave Conference,2004.34th European .

[0092] Liquid crystal is poured into a polytetrafluoroethylene (PTFE) or fused silica capillary, and the capillary filled with liquid crystal is inserted into the middle of the resonant chamber. Then an input signal source is applied, and the output signal result is recorded with a vector network analyzer. The changes in the resonant frequency and Q factor between the capillary filled with liquid crystal and the blank capillary are measured, and the dielectric constant and loss tangent are calculated. The dielectric constant components perpendicular and parallel to the liquid crystal director are obtained by the orientation of the liquid crystal in the magnetic field, and the direction of the magnetic field is set accordingly, and then rotated 90° accordingly.

[0093] The preferred liquid crystal composition of the present invention has a tuning rate τ≥0.25, more preferably τ≥0.28; the preferred vertical dielectric loss tanδ of the liquid crystal material is ⊥ ≤0.006, more preferably tanδ ⊥≤0.005; material quality factor η≥50, preferably η≥60. The nematic phase temperature range of the liquid crystal composition of the present invention is 0 to 90°C or above, preferably the nematic phase temperature range is -10 to 100°C or above; more preferably the nematic phase temperature range of the liquid crystal composition is -20 to 120°C or above. The dielectric constant of the liquid crystal composition of the present invention at a low frequency of 1KHz is ≥6.0, more preferably ≥7.0.

[0094] The liquid crystal composition according to the invention is very suitable for preparing microwave components, which can operate in the UHF band (0.3-1 GHz), L band (1-2 GHz), S band (2-4 GHz), C band (4-8 GHz), X band (8-12 GHz), Ku band (12-18 GHz), K band (18-27 GHz), Ka band (27-40 GHz), V band (50-75 GHz), W band (75-110 GHz) and up to 1 THz. The construction of phase shifters according to the present application is known to experts. Typically, loaded line phase shifters, inverted microstrip lines, fin line phase shifters, preferably antipodal fin line phase shifters, slotted phase shifters, microstrip line phase shifters or coplanar waveguide (CPW) phase shifters are used. These components can realize reconfigurable antenna arrays.

[0095] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0096] The liquid crystal compound and the composition thereof of the present invention have ultra-low dielectric loss, large dielectric tuning rate and very high quality factor at high frequency, and also have a wide liquid crystal operating temperature range. DETAILED DESCRIPTION

[0097] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0098] The present invention is further described in detail below in conjunction with specific embodiments.

[0099] The mixed liquid crystal is tested for physical properties and photoelectric properties. The detailed test methods for the physical properties and photoelectric properties involved in the present invention are as follows:

[0100] (1) Clearing point (Tni):

[0101] Polarized light hot stage method: Apply the liquid crystal sample on a glass slide and place it in an orthogonal polarized light microscope hot stage, and set the heating rate to 2°C / min. The temperature at which the liquid crystal sample starts to turn black from bright state under a polarized light microscope is the clearing point.

[0102] Alternatively, differential scanning calorimetry was used: under nitrogen atmosphere, the heating rate was set to 2°C / min.

[0103] (2) Low temperature storage temperature (LTS): Place about 1 mL of mixed liquid crystal into a transparent glass bottle and place it in a low temperature refrigerator. Set the temperature to -20℃, -30℃, and -40℃, store for 10 days respectively, and observe whether there is crystal precipitation or smectic phase. If no crystal precipitation occurs at -30℃, LTS ≤ -30℃.

[0104] (3) Birefringence (Δn): Using an Abbe refractometer, at a constant temperature of 25°C and a light source of 589 nm, the ordinary light (n o ) and extraordinary light (n e ) refractive index, birefringence Δn = n e -n o .

[0105] (4) Dielectric constant (Δε): Tested with an LCR meter at a constant temperature of 25°C. Δε = ε ∥ -ε ⊥ , that is, the dielectric constant along the long axis of the molecule (ε ∥ ) and the dielectric constant along the molecular short axis (ε ⊥ ) is the difference between .

[0106] (5) Elastic constant (K 11 , K 33 ): Under the condition of 25℃ constant temperature, the capacitance-voltage (CV) curve of liquid crystal is tested and K is obtained by fitting. 11 and K 33 .

[0107] (6) Rotational viscosity (γ1): Under a constant temperature of 25°C, by applying voltage to the liquid crystal test box, the instantaneous current value Ip of the liquid crystal molecules deflected by the electric field movement is tested, and the rotational viscosity γ1 is calculated.

[0108] See Table 3-5 for codes and descriptions:

[0109] Table 3 Physical parameters

[0110]

[0111]

[0112] Table 4 Structural abbreviations

[0113]

[0114] Table 5 Examples of abbreviations

[0115]

[0116] Liquid crystal phase transition temperature: C represents melting point, S represents smectic phase, N represents nematic phase, and Iso represents liquid state.

[0117] Example 1: Synthesis of 1-isothiocyanate-2,3-dimethyl-4-((4-n-butylphenyl)ethynyl)benzene

[0118] The synthesis method is as follows:

[0119]

[0120] Abbreviated as: 5PTP(M-2,3)S;

[0121] Synthesis step 1: Under nitrogen protection, add 24.7g 2,3-dimethyl-4-iodoaniline, 200mL triethylamine, 2.1g ditriphenylphosphine palladium chloride, and 1.1g cuprous iodide to a three-necked flask, stir and heat to above 40°C, and slowly drop 100mL of triethylamine solution containing 17.2g 4-n-pentylphenylacetylene. After the addition is complete, heat to 50-60°C and continue stirring and reacting for 2h. Cool to room temperature, filter to remove the salt produced by the reaction, and remove triethylamine by vacuum distillation. Add 200mL toluene and wash with water until neutral. Concentrate to remove the solvent, and the resulting product is recrystallized from petroleum ether to obtain 27g of brown solid.

[0122] Synthesis step 2: Add 27g of the brown solid obtained in the previous step to a three-necked flask, add 200mL of chloroform and 50mL of water, cool to below 5°C, and slowly drop 15.5g of thiophosgene. After the addition is complete, heat to reflux for 2h. Cool to room temperature, separate the liquids, wash the organic layer with sodium bicarbonate aqueous solution, and then wash with water until neutral. Remove the solvent by vacuum distillation, and pass the resulting product through a silica gel column and elute with n-heptane. The product is recrystallized from n-heptane to obtain 23.4g of a white solid with a gas chromatographic purity of 99.8%.

[0123] The structural identification data are as follows:

[0124] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.89 (d, J=7.5Hz, 3H), 1.32–1.33 (m, 4H), 1.61 (m, 2H), 2.31 (s, 3H), 2.47 ( s,3H),2.59-2.62(m,2H),7.04–7.07(m,1H),7.14–7.17(m,2H),7.30–7.33(m,1H),7.41–7.44(m,2H).

[0125] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.1, 15.6, 18.3, 22.7, 31.0, 31.6, 36.1, 87.7, 95.0, 120.5, 123.0, 123.9, 128.7, 130.2, 130.3, 133.5, 140.3, 143.9.

[0126] MS m / z(RI,%):333.2(M + ,100),276.1(89),202.1(17),121.5(2).

[0127] DSC: C 64.39N (59.78) Iso.

[0128] Example 2: Synthesis of 1-isothiocyanate-2,6-dimethyl-4-((4-n-pentylphenyl)ethynyl)benzene

[0129] Abbreviated as: 5PTP(M-2,6)S;

[0130] Substituting 2,6-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 1-isothiocyanate-2,6-dimethyl-4-((4-n-pentylphenyl)ethynyl)benzene was obtained by the same synthesis method as in Example 1.

[0131] The structural identification data are as follows:

[0132] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.89 (t, J = 7Hz, 3H), 1.28–1.38 (m, 4H), 1.57–1.63 (m, 2H) ),2.34(s,6H),2.59(t,J=7.5Hz,2H),7.19(d,J=8Hz,2H),7.47(d,2H),7.56(s,2H).

[0133] 13 CNMR (125MHz, CDCl3) δ (ppm): 14.1, 17.7, 20.1, 22.6, 30.9, 31.5, 35.9, 86.9, 95.2, 120.4, 122.6, 126.7, 128.6, 131.5, 133.7, 136.2, 138.9, 143.7.

[0134] MS m / z(RI,%):333.3(M +,100),276.2(90),244.2(2),202.1(18),189.1(3).

[0135] DSC: C 43.26Iso.

[0136] Example 3: Synthesis of 4-((4-isothiocyanate-3,5-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl

[0137] Abbreviated as: 5PPTP(M-2,6)S;

[0138] Substituting 4'-n-pentyl-4-ethynylbiphenyl for 4-n-pentylphenylacetylene in Example 1, and substituting 2,6-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 4-((4-isothiocyanate-3,5-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl was obtained by the same synthesis method as in Example 1.

[0139] The structural identification data are as follows:

[0140] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.90 (t, J = 7Hz, 3H), 1.33-1.37 (m, 4H), 1.61-1.67 (m, 2H), 2.34 (s, 6 H),2.63(t,J=8Hz,2H),7.21(s,2H),7.24(d,J=8Hz,2H),7.50(d,J=8Hz,2H),7.53–7.56(m,4H).

[0141] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.1, 18.7, 22.7, 31.2, 31.7, 35.8, 89.3, 91.0, 121.7, 1 22.1,127.0,129.1,129.7,131.3,132.2,135.4,136.8,137.8,141.4,141.8,142.9.

[0142] MS m / z(RI,%):MS m / z(RI,%):409.2(M + ,100),352.1(73),320.1(4),277.1(3),175.9(10).

[0143] DSC: C 121.99N 153.19Iso.

[0144] Example 4: Synthesis of 4-((4-isothiocyanate-2,3-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl

[0145] Abbreviated as: 5PPTP(M-2,3)S;

[0146] 4-((4-isothiocyanate-2,3-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl was obtained by using the same synthesis method as in Example 1, by replacing 4-n-pentylphenylacetylene in Example 1 with 4'-n-pentyl-4-ethynylbiphenyl.

[0147] The structural identification data are as follows:

[0148] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.90 (t, J = 7Hz, 3H), 1.33–1.37 (m, 4H), 1.50–1.52 (m, 2H), 2.33 (s, 2H), 2.49 (s, 2H), 2.64 (d,J=7.5Hz,2H),7.07(t,J=8Hz,1H),7.24–7.26(m,3H),7.34(d,J=8.5Hz,1H),7.50–7.52(m,1H),7.53–7.58(m,4H).

[0149] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.1, 15.6, 18.4, 22.7, 31.2, 31.7, 35.8, 88.9, 94.8, 121.9, 122. 9,123.9,127.0,127.0,129.1,130.4,130.6,132.1,133.5,136.0,137.8,140.4,141.4,142.9.

[0150] MS m / z(RI,%):409.2(M + ,100),377.1(6),352.1(61),294.1(18),253.0(6),176.2(9).

[0151] DSC: C 99.31S 194.30N 254.89 ISO.

[0152] Example 5: Synthesis of 4-((4-isothiocyanate-2,5-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl

[0153] Abbreviated as: 5PPTP(M-2,5)S;

[0154] Substituting 4'-n-pentyl-4-ethynylbiphenyl for 4-n-pentylphenylacetylene in Example 1, and substituting 2,5-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 4-((4-isothiocyanate-2,5-dimethylphenyl)ethynyl)-4'-n-pentylbiphenyl was obtained by the same synthesis method as in Example 1.

[0155] The structural identification data are as follows:

[0156] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.91 (t, J = 7Hz, 3H), 1.31–1.38 (m, 4H), 1.63–1.69 (m, 2H), 2.34 (s, 3H), 2.46 (s, 3H) ),2.65(t,J=8Hz,2H),7.07(s,1H),7.26(d,J=8Hz,2H),7.35(s,1H),7.52(d,J=8.5Hz,2H),7.55–7.59(m,4H).

[0157] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.1, 17.9, 20.2, 22.7, 31.3, 31.7, 35.8, 88.2, 95.1, 121.9, 122. 6,127.0,127.0,127.1,129.1,130.0,132.1,132.3,133.9,136.3,137.8,139.2,141.5,142.9.

[0158] MS m / z(RI,%):409.2(M + ,100),352.1(57),294.1(14),204.5(4),175.9(11).

[0159] DSC: C 97.66N 153.60 Iso.

[0160] Example 6: Synthesis of 4-((4-isothiocyanate-2-methylphenyl)ethynyl-3-methyl)-4'-n-pentylbiphenyl

[0161] Abbreviated as: 5PP(M-2)TP(M-3)S;

[0162] Substituting 4'-n-pentyl-3-methyl-4-ethynylbiphenyl for 4-n-pentylphenylacetylene in Example 1, and substituting 3-methyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 4-((4-isothiocyanate-2-methylphenyl)ethynyl-3-methyl)-4'-n-pentylbiphenyl was obtained by the same synthesis method as in Example 1.

[0163] The structural identification data are as follows:

[0164] 1 H NMR (500MHz, CDCl3) δ (ppm): 0.91 (t, J = 7Hz, 3H), 1.31–1.40 (m, 4H), 1.62–1.68 (m, 2H), 2.51 (s, 3H), 2.57 (s, 3H), 2.65 (t, J = 7.5 Hz,2H),7.04(dd,J1=8Hz,J2=1.5Hz,1H),7.12(s,1H),7.25(d,J=8Hz,2H),7.41(dd,J1=8Hz,J2=1.5Hz,1H),7.47-7.55(m,5H).

[0165] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.2, 21.0, 21.2, 22.7, 31.3, 31.7, 35.8, 91.9, 94.6, 121.6, 123. 0,123.2,124.4,126.9,127.0,128.3,129.1,132.5,133.0,137.9,140.5,141.6,141.8,142.8.

[0166] MS m / z(RI,%):409.2(M + ,100),352.1(52),294.1(13),277.1(4),204.7(3),176.0(7).

[0167] DSC: C 78.21N 183.71 Iso.

[0168] Example 7: 1-isothiocyanate-2,3-dimethyl-4-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene

[0169] Abbreviated as: 5CPTP(M-2,3)S;

[0170] Substituting 4-(4-n-pentylcyclohexyl)phenylacetylene for 4-n-pentylphenylacetylene in Example 1, the same synthesis method as in Example 1 was used to obtain 1-isothiocyanate-2,3-dimethyl-4-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene.

[0171] 1 H NMR(500MHz, CDCl3)δ(ppm):0.89(t,3H),0.99–1.08(m,2H),1.20–1.45(m,11H),1.87-1.90(m,4H),2.31(s,3H) ,2.44(t,J=12Hz,1H),2.47(s,3H),7.04–7.07(m,1H),7.14–7.17(m,2H),7.30–7.33(m,1H),7.41–7.44(m,2H).

[0172] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.2, 18.7, 22.9, 26.8, 32.4, 33.7, 34.4, 37.5, 39.1, 44.8,87.7,95.0,120.5,123.0,123.9,128.7,130.2,130.3,133.5,140.3,143.9.

[0173] MS m / z(RI,%):415.4(M + ,100),302.2(8),276.2(19),229.2(13).

[0174] DSC: C 105.96N 244.02 Iso.

[0175] Example 8: 2-isothiocyanate-1,3-dimethyl-5-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene

[0176] Abbreviated as: 5CPTP(M-2,6)S;

[0177] Substituting 4-(4-n-pentylcyclohexyl)phenylacetylene for 4-n-pentylphenylacetylene in Example 1, and substituting 2,6-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, the same synthetic method as in Example 1 was used to obtain 2-isothiocyanate-1,3-dimethyl-5-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene.

[0178] The structural identification data are as follows:

[0179] 1H NMR (500MHz, CDCl3) δ (ppm): 0.89 (t, 3H), 0.98–1.05 (m, 2H), 1.19–1.44 (m, 11H), 1.88-1. 91(m,4H),2.31(s,6H),2.44(t,J=12Hz,1H),7.13–7.15(m,4H),7.38–7.39(d,J=8Hz,2H).

[0180] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.2, 18.7, 22.9, 26.8, 32.4, 33.7, 34.4, 37.5, 39.1, 44.8,88.1,91.3,120.5,122.3,127.1,129.5,131.2,131.8,135.3,136.7,148.8.

[0181] MS m / z(RI,%):415.4(M + ,100),302.2(6),276.1(16),229.1(10),215.1(2).

[0182] DSC: C 81.87N 158.72 Iso.

[0183] Example 9: 1-isothiocyanate-2,5-dimethyl-4-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene

[0184] Abbreviated as: 5CPTP(M-2,5)S;

[0185] Substituting 4-(4-n-pentylcyclohexyl)phenylacetylene for 4-n-pentylphenylacetylene in Example 1, and substituting 2,5-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, the same synthetic method as in Example 1 was used to obtain 1-isothiocyanate-2,5-dimethyl-4-((4-(4-n-pentylcyclohexyl)phenyl)ethynyl)benzene.

[0186] The structural identification data are as follows:

[0187] 1H NMR (500MHz, CDCl3) δ (ppm): 0.90 (t, J = 7.5Hz, 3H), 1.06–1.31 (m, 11H), 1.50–1.53 (m, 2H), 1.87 (m, 4H), 2.34 (m, 3 H),2.46(s,3H),2.62(t,1H),7.04–7.05(d,J=7Hz,1H),7.17–7.20(m,2H),7.24–7.27(m,1H),7.41–7.43(m,2H).

[0188] 13 C NMR (125MHz, CDCl3) δ (ppm): 14.2, 17.7, 20.1, 22.8, 26.7, 32.3, 33.6, 34.2, 37.4, 37.4, 44. 7,86.9,95.3,120.5,122.6,126.7,128.0,129.7,131.5,132.1,133.7,136.2,139.0,148.6.

[0189] MS m / z(RI,%):415.4(M + ,100),302.2(4),276.1(11),229.1(9),215.1(4).

[0190] DSC: C 77.44N 157.95 Iso.

[0191] Example 10: 4-isothiocyanate-2,5-dimethyl-4"-n-pentyl-1,1':4',1"-terphenyl

[0192]

[0193] Abbreviated as: 5PPP(M-2,5)S;

[0194] Synthesis step 1: Under nitrogen protection, add 24.7g 2,5-dimethyl-4-iodoaniline, 26.8g 4'-pentylbiphenylboric acid, 1.2g tetrakis(triphenylphosphine)palladium, 27.6g potassium carbonate, 100ml toluene, 100ml ethanol, and 100ml water into a three-necked flask, stir and heat to reflux, and react for 8h. Cool to room temperature, add 100mL toluene, and separate the organic layer. Wash the organic layer with water until neutral, and concentrate to remove the solvent. The obtained product is recrystallized from petroleum ether to obtain 27.8g of brown solid.

[0195] Synthesis step 2: Add 27.8g of the brown solid obtained in the previous step to a three-necked flask, add 200mL of chloroform and 50mL of water, cool to below 5°C, and slowly drop 14.0g of thiophosgene. After the addition is complete, heat to reflux for 2h. Cool to room temperature, separate the liquids, wash the organic layer with sodium bicarbonate aqueous solution, and then wash with water until neutral. Remove the solvent by vacuum distillation, and pass the resulting product through a silica gel column and elute with n-heptane. The product is recrystallized from n-heptane to obtain 23.7g of a white solid with a gas chromatographic purity of 99.9%.

[0196] The structural identification data are as follows:

[0197] 1 HNMR: 0.91(t,J=7Hz,3H),1.35–1.39(m,4H),1.64–1.70(m,2H),2.25(s,3H),2.38(s,3H),2.66(t,J=8Hz,2H), 7.12(d,J=3Hz,2H),7.27(d,J=8.5Hz,2H),7.33(q,J=8.5Hz,2H),7.55(d,J=8.5Hz,2H),7.63(d,J=8.5Hz,2H).

[0198] 13 CNMR: 14.2,18.0,20.1,22.7,31.3,31.7,35.8,110.2,126.9,127.1,127.7,1 29.1,129.3,129.5,132.2,132.3,134.5,138.1,139.5,140.3,141.1,142.5.

[0199] MS m / z (RI,%): 385.3 (M + ,100),328.2(91),296.2(24),255.1(4),164.1(5).

[0200] DSC: C 76.79 Iso.

[0201] Example 11: 4-(4-butylcyclohexyl)-4'-((4-isothiocyanato-2,5-dimethylphenyl)ethynyl)-1,1'-biphenyl

[0202] Abbreviated as: 4CPPTP(M-2,5)S;

[0203] Substituting 4'-(4-n-butylcyclohexyl)-4-ethynylbiphenyl for 4-n-pentylphenylacetylene in Example 1, and substituting 2,5-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 4-(4-butylcyclohexyl)-4'-((4-isothiocyanato-2,5-dimethylphenyl)ethynyl)-1,1'-biphenyl was obtained by the same synthesis method as in Example 1.

[0204] The structural identification data are as follows:

[0205] 1 HNMR: 0.90(t,3H),1.31~1.61(m,15H),2.34(s,3H),2.48(s,3H),2.72(m,1H), 7.03(s,1H),7.36(d,2H),7.37(d,2H),7.62(d,2H),7.65(d,2H),7.78(s,1H). .

[0206] 13 CNMR: 14.4,17.0,19.6,23.0,29.5,29.6,30.9(2C),31.2(2C),43.7,88.3,95.2,121.6,122 .5,127.1,127.6(2C),128.5(2C),129.2(2C),130.9,132.8(2C),138.0,140.5(2C),145.9.

[0207] DSC: C121.15 N>300 Iso.

[0208] Example 12: 4-(4-((4-isothiocyanato-2,5-dimethylphenyl)ethynyl)phenyl)-4'-propyl-1,1'-bicyclohexane

[0209] Abbreviated as: 3CCPTP(M-2,5)S;

[0210] Substituting 4-(4-ethynylphenyl)-4'-propyl-1,1'-bicyclohexane for 4-n-pentylphenylacetylene in Example 1, and substituting 2,5-dimethyl-4-iodoaniline for 2,3-dimethyl-4-iodoaniline in Example 1, 4-(4-((4-isothiocyanato-2,5-dimethylphenyl)ethynyl)phenyl)-4'-propyl-1,1'-bicyclohexane was obtained by the same synthesis method as in Example 1.

[0211] The structural identification data are as follows:

[0212] 1HNMR: 0.90(t,3H),1.25~1.61(m,23H),2.34(s,3H),2.48(s,3H),2.72(m,1H),7.03(s,1H),7.26(d,2H),7.51(d,2H),7.78(s,1H).

[0213] 13 CNMR:14.4,17.0,19.6,20.5,23.5(2C),26.8(2C),29.3,30.9(2C),31.4(2C),37.1,41.6(2C),4 3.1,88.3,95.3,119.9,122.5,126.1(2C),127.1,129.0,130.9,132.0(2C),134.5,140.5,146.7.

[0214] DSC: C 118.92N 288.88 Iso.

[0215] Embodiment 13:

[0216] Liquid crystal composition M0: composed of the monomeric liquid crystal compounds in Table 6.

[0217] Table 6 Composition of liquid crystal composition M0

[0218] Monomer Liquid Crystal Mass ratio / % 2CPUS 25 3CPUS 25 5CPUS 25 3CCV 25

[0219] In order to evaluate the performance of the newly synthesized liquid crystal compound, the liquid crystal compounds prepared in Examples 7 to 9 and 11 were uniformly mixed with M0 at a mass ratio of 15:85 to obtain test compositions M1 to M4, as shown in Table 7 for details.

[0220] Table 7 Liquid crystal composition mass ratio

[0221] Composition Compound Mass ratio (compound: M0) M1 (Example 7) 5CPTP(M-2,3)S 15:85 M2 (Example 8) 5CPTP(M-2,6)S 15:85 M3 (Example 9) 5CPTP(M-2,5)S 15:85 M4 (Example 11) 4CPPTP(M-2,5)S 15:85

[0222] Liquid crystal compositions M0 to M4 were respectively poured into polytetrafluoroethylene tubes, and the dielectric constant and loss tangent value at 19 GHz were tested by cavity perturbation method at 25° C., and the quality factor was calculated. The results are shown in Table 8 below.

[0223] Table 8 Microwave performance of M0~M4

[0224]

[0225]

[0226] From the test data in the table, it can be found that after adding the compound of the present invention to M0, the obtained liquid crystal compositions M1 to M4 have a tan δ ⊥There is a significant decrease, Δε increases, and η increases significantly.

[0227] Embodiment 14:

[0228] The performance data of the liquid crystal composition and mass ratio are shown in Table 9.

[0229] Table 9 Liquid crystal composition and properties of Example 14

[0230]

[0231] Embodiment 15:

[0232] The performance data of the liquid crystal composition and mass ratio are shown in Table 10.

[0233] Table 10 Liquid crystal composition and properties of Example 15

[0234]

[0235]

[0236] Embodiment 16:

[0237] The performance data of the liquid crystal composition and mass ratio are shown in Table 11.

[0238] Table 11 Liquid crystal composition and properties of Example 16

[0239]

[0240]

[0241] Embodiment 17:

[0242] The performance data of the liquid crystal composition and mass ratio are shown in Table 12.

[0243] Table 12 Liquid crystal composition and properties of Example 17

[0244]

[0245] Comparative Example 1:

[0246] Patent CN107955630A discloses a compound 5CPTUS having two lateral fluorine atoms at the molecular end, and the structural formula is as follows:

[0247]

[0248] The monomer liquid crystal was uniformly mixed with M0 at a mass ratio of 15:85 to obtain a liquid crystal composition M5.

[0249] Chinese patent application 202010288457.2 discloses an isothiocyanate liquid crystal having three ring structures, the structure of which is shown in the figure below:

[0250]

[0251] This monomer liquid crystal is uniformly mixed with M0 in a mass ratio of 15:85 to obtain a liquid crystal composition M6.

[0252] The physical properties of liquid crystal compositions M5 and M6 at 19 GHz were tested at 25°C. The data are shown in Table 12.

[0253] Table 12 Test data of liquid crystal composition of comparative example 1

[0254] Liquid crystal composition <![CDATA[ε ⊥ ]]> <![CDATA[ε ∥ ]]> ∆ε <![CDATA[tanδ ⊥ ]]> <![CDATA[tanδ ∥ ]]> τ η M5 2.365 3.080 0.715 0.0112 0.0050 0.232 20.74 M6 2.402 3.106 0.704 0.0096 0.0042 0.227 23.65

[0255] By comparing the liquid crystal compositions M5-M6 of comparative example 1 with the liquid crystal compositions M1-M4 of example 12, it can be seen that the liquid crystal compounds of the present invention have significantly reduced dielectric loss and a larger quality factor η at high frequencies.

[0256] Comparative Example 2:

[0257] CN107955630A discloses a liquid crystal composition for high-frequency components, wherein the components are selected from fluorine-substituted isothiocyanate liquid crystal compounds. In its Example 1, the following composition and performance parameters are disclosed, as shown in Table 13:

[0258] Table 13 Mass ratio and performance of liquid crystal composition of comparative example 2

[0259]

[0260]

[0261] Compared with Comparative Example 2, the dielectric loss of Examples 14 to 17 of the liquid crystal composition of the present invention is greatly reduced and the quality factor is doubled.

[0262] Comparative Example 3:

[0263] Example N52 in patent CN110499163A discloses a composition containing a fluorine-substituted isothiocyanate liquid crystal compound and its high-frequency dielectric constant and other properties, as shown in Table 14:

[0264] Table 14 Performance data of liquid crystal composition of comparative example 3

[0265]

[0266]

[0267] Compared with comparative example 3, the dielectric loss of liquid crystal composition examples 14-17 of the present invention is greatly reduced and the quality factor is doubled.

[0268] The preferred embodiments of the present disclosure are described in detail above; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0269] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0270] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A liquid crystal compound with ultra-low dielectric loss, characterized in that: The specific compounds are shown in the following table: Wherein R is selected from an alkyl group having 1 to 10 carbon atoms, X1 to X8 are methyl groups or hydrogen, and at least two substituents among X1 to X8 are methyl groups.

2. The liquid crystal compound with ultra-low dielectric loss according to claim 1, characterized in that: The structural formula of the compound is shown in the following table: 。 3. A liquid crystal composition with ultra-low dielectric loss, characterized in that: Contains one or more liquid crystal compounds with ultra-low dielectric loss selected from any one of claims 1-2.

4. The liquid crystal composition with ultra-low dielectric loss according to claim 3, characterized in that: Calculated by mass percentage, the content of the liquid crystal compound with ultra-low dielectric loss is 1% to 100%.

5. The liquid crystal composition with ultra-low dielectric loss according to claim 3 or 4, characterized in that: Contains one or more compounds selected from the general structural formula II as the second component: ； wherein R2 and R3 are respectively an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a fluorinated alkyl group, a fluorinated alkenyl group, a cycloalkyl group, a halogen group or NCS; Ring A and Ring B are respectively a benzene ring, cyclohexane, cyclohexene or a benzene ring in which hydrogen atoms are replaced by fluorine atoms; Calculated by mass percentage, the content of the compound represented by general structural formula II is 0% to 40%.

6. The liquid crystal composition with ultra-low dielectric loss according to claim 5, characterized in that: Contains one or more compounds selected from the general structural formula III as the third component: ； wherein R1 is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a fluorinated alkyl group, a fluorinated alkenyl group or a cycloalkyl group; 13 is selected from H, F, methyl and ethyl, and X9 to X 13 One of them is methyl or ethyl; k, m and n are 0 or 1; Ring A is benzene ring, cyclohexane or cyclohexene; Calculated by mass percentage, the content of the compound represented by the general structural formula III is 0% to 90%.

7. The liquid crystal composition with ultra-low dielectric loss according to claim 6, characterized in that: Contains one or more compounds selected from the general structural formula IV as the fourth component: ； wherein R1 is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a fluorinated alkyl group, or a fluorinated alkenyl group; 14 ~X 17 is H, methyl, ethyl, and X 14 ~X 17 One of them is methyl or ethyl, and the rest are H; Calculated by mass percentage, the content of the compound represented by the general structural formula IV is 0% to 50%.

8. The liquid crystal composition with ultra-low dielectric loss according to claim 3 or 4, characterized in that: The liquid crystal composition has: Tuning rate τ ≥0.25, vertical dielectric loss tanδ ⊥ ≤0.006, material quality factor η≥50, nematic phase temperature range is 0~90℃, low frequency 1KHz dielectric constant ≥6.

0.

9. A high frequency component, characterized in that: The high-frequency component comprises the liquid crystal compound with ultra-low dielectric loss described in any one of claims 1-2 or the liquid crystal composition with ultra-low dielectric loss described in any one of claims 3-8.

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