CN109265713B - Method for constructing single-domain liquid crystal elastomer by liquid crystal polymer modified nano particles - Google Patents

Method for constructing single-domain liquid crystal elastomer by liquid crystal polymer modified nano particles Download PDF

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CN109265713B
CN109265713B CN201811144267.2A CN201811144267A CN109265713B CN 109265713 B CN109265713 B CN 109265713B CN 201811144267 A CN201811144267 A CN 201811144267A CN 109265713 B CN109265713 B CN 109265713B
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谢鹤楼
胡俊
匡泽洋
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Xiangtan University
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Abstract

The invention discloses a method for constructing a single-domain liquid crystal elastomer by using liquid crystal polymer modified nano particles. Firstly, preparing liquid crystal polymer modified nano particles, spin-coating the nano particles on the surface of a cover glass, and annealing to prepare a liquid crystal box. And then blending the liquid crystal monomer, the cross-linking agent and the initiator to form a uniform liquid crystal mixture, sucking the obtained liquid crystal mixture into a liquid crystal box above the isotropic temperature of the liquid crystal mixture, slowly cooling to a liquid crystal phase interval of the mixture, and carrying out in-situ polymerization on the liquid crystal mixture in the temperature interval to obtain the single-domain oriented liquid crystal elastomer film. The method utilizes the nano particles modified by the liquid crystal polymer to construct the single-domain liquid crystal elastomer, can generate special thermotropic deformation, is simple and easy to prepare the liquid crystal elastomer, has high orientation degree, and has potential application value in the aspects of artificial muscles, sensors, actuators and the like.

Description

Method for constructing single-domain liquid crystal elastomer by liquid crystal polymer modified nano particles
Technical Field
The invention discloses a method for preparing a vertically-oriented liquid crystal elastomer, belongs to the technical field of materials, and particularly relates to a method for constructing a single-domain liquid crystal elastomer by using liquid crystal polymer modified nano particles.
Background
The liquid crystal elastomer is formed by partially crosslinked liquid crystal macromolecules, and is a shape memory material combining the ordering of liquid crystal and the soft elasticity of a three-dimensional space network structure. When the temperature of the monodomain-oriented liquid crystal elastomer is raised to the isotropic transition temperature, the oriented liquid crystal primitives are changed from order to disorder to cause the change of the shape of the material, and the original shape can be recovered when the temperature is reduced to a liquid crystal phase interval, so that the reversible shape change enables the liquid crystal elastomer to have potential application values in the aspects of sensors, actuators, artificial muscles and the like. The monodomain orientation liquid crystal elastomer is prepared by a two-step method generally, but the synthesis method is complex and high in cost, and most of the monodomain orientation liquid crystal elastomers are parallel orientation liquid crystal elastomers.
In order to prepare the single-domain oriented liquid crystal elastomer, the invention tries to utilize nano particles modified by liquid crystal macromolecules as a substrate to induce the orientation of liquid crystal monomers, and then utilizes an in-situ polymerization one-step method to quickly prepare the single-domain liquid crystal elastomer. Meanwhile, the single-orientation liquid crystal elastomer can generate thermal deformation, so that the preparation process is simplified, the process cost is reduced, and more feasible selection schemes are provided for the application of shape memory materials in the future.
Disclosure of Invention
The invention aims to provide a method for constructing a single-domain liquid crystal elastomer by using nanoparticles modified by liquid crystal polymers.
The technical scheme of the invention is as follows:
a method for constructing a single-domain liquid crystal elastomer by using liquid crystal polymer modified nano particles. The method comprises the following steps:
(1) preparing liquid crystal polymer modified nano particles, dissolving the obtained liquid crystal polymer modified nano particles in an organic solvent, spin-coating on a cover glass, and annealing to prepare a liquid crystal box.
(2) The liquid crystal monomer, the cross-linking agent and the initiator are blended and dissolved in the organic solvent, and a uniform liquid crystal mixture is formed after the solvent is volatilized.
(3) And (3) sucking the obtained liquid crystal mixture into a liquid crystal box, annealing, carrying out in-situ polymerization, crosslinking a liquid crystal monomer to form a liquid crystal elastomer, and removing a glass substrate to obtain the single-domain oriented liquid crystal elastomer film.
Further, the structure of the liquid crystal polymer modified nanoparticles in the step (1) is shown as formula I:
Figure BDA0001816451460000021
in the formula I, M is one of gold nanoparticles, nickel nanoparticles, carbon nanotubes and polyhedral oligomeric silsesquioxane (POSS);
in the formula I, N is one of sulfur, alkyl, alkoxy, ester group and carbonyl;
in the formula I, n is more than or equal to 30, A is one of alkyl, alkoxy, ester group and carbonyl;
in the formula I, B is one of hydrogen, alkyl or alkoxy;
in the formula I, C is one of the formulas II:
Figure BDA0001816451460000022
in the formula II, wherein R1Is (CH)2)n，(CH2)nO, and n is more than or equal to 0 and less than or equal to 18;
wherein R is2Is H, (CH)2)nCH3，O(CH2)nCH3，NH(CH2)nCH3，CN， NO2，SO3One of Na, and n is more than or equal to 0 and less than or equal to 18.
Further, the molecular structure of the liquid crystal monomer in the step (2) is shown as a formula III:
Figure BDA0001816451460000031
in the formula III, wherein R1Is (CH)2)nAnd n is more than or equal to 0 and less than or equal to 10;
wherein R is2Is (CH)2)n，(CH2)nAnd n is more than or equal to 0 and less than or equal to 10.
Further, the molecular structure of the cross-linking agent in the step (2) is shown as a formula IV:
Figure BDA0001816451460000032
in the formula IV, R3Is (CH)2)nAnd n is more than or equal to 0 and less than or equal to 10;
wherein R is4Is H, CH3One of (1) and (b).
Further, the initiator in the step (2) is one of a thermal initiator and a photoinitiator. Wherein the photoinitiator is one of 2, 2-dimethoxy-2-phenyl acetophenone, methyl o-benzoylbenzoate and 2-hydroxy-2-methylphenyl propane-1-ketone. Wherein the thermal initiator is one of azodiisobutyronitrile, azodiisoheptonitrile and dibenzoyl peroxide.
Further, the organic solvent used for forming a uniform mixture in the step (2) is one of dichloromethane, chloroform and acetone.
Further, the temperature of the mixture absorbed into the liquid crystal cell in the step (3) is above the isotropic temperature of the mixture.
Further, the in-situ polymerization in the step (3) is one of photo-initiated polymerization and thermal initiated polymerization.
Further, in the step (3), a hydrofluoric acid solution is used for etching the cover glass to obtain the liquid crystal elastomer film.
The invention has the following technical effects:
(1) the invention utilizes the nano particles modified by liquid crystal polymers as the substrate to prepare the liquid crystal elastomer, is synthesized by a one-step method, has simple operation and low cost, and provides a new synthesis method for preparing soft elastic materials.
(2) The liquid crystal elastomer prepared by the invention has uniform single domain orientation, has special thermotropic deformation, and has potential application value in the aspects of actuators, artificial muscles and the like.
Drawings
FIG. 1 is a polarization diagram of the orientation of the mixture of the liquid crystal monomer, the crosslinking agent and the photoinitiator in the liquid crystal cell in example 1 (the upper right corner is a conoscopic diagram);
FIG. 2 is a two-dimensional wide-angle X-ray diffraction pattern of the single-domain liquid crystal elastomer film in example 1;
FIG. 3 is a diagram showing the thermotropic deformation of a single-domain liquid-crystalline elastomer film in example 1.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the present invention is not limited thereto.
Example 1
A method for preparing a single-domain oriented liquid crystal elastomer by using gold nanoparticles modified by biphenyl liquid crystal macromolecules comprises the following steps:
raw materials: 4- (6-acryloyloxyhexyloxy) -4' -cyanobiphenyl, 1, 4-bis- [4- (6-acryloyloxyhexyloxy) benzoyloxy]-2-methylbenzene, 2, 2-dimethoxy-2-phenylacetophenone, ethylene glycol, 2-bromo-2-methylpropanoyl bromide, triethylamine, pentamethyldiethylenetriamine, cuprous bromide, alpha-lipoic acid, tetrachloroauric acid trihydrate, tetraoctylammonium bromide, sodium borohydride, 4-dimethylaminopyridine, Tetrahydrofuran (THF), toluene, alumina (Al)2O3)。
(1) Synthesis of biphenyl liquid crystal polymer modified gold nanoparticles and preparation of liquid crystal box
Liquid crystal monomer: 6- [ 4' - (4-phenoxy) p-butylbiphenyl ] hexyl methacrylate
Catalyst: cuprous bromide (CuBr)
Initiator: isobromobutyric acid Hydroxyethyl Ester (HEBI)
Ligand: pentamethyldiethylenetriamine (PMDETA)
A small magneton, a monomer, PMDETA, CuBr and HEBI (molar charge ratio is n: 1: 1: 1, wherein n is the polymerization degree of a target polymer, and n is 50) are put into a clean polymerized glass tube in sequence. Then, purified chlorobenzene was added as a solvent, and the reaction concentration was adjusted to 30%. After freezing, vacuumizing and nitrogen blowing for more than three times, vacuum sealing the tube, placing the tube in a constant-temperature oil bath at 75 ℃, reacting for 6 hours at constant temperature, taking out the polymerization tube, placing the tube in an ice-water bath, and stopping the polymerization reaction. The polymerization tube was carefully knocked open, the polymer solution was diluted with chlorobenzene solution and added dropwise to the solution containing AlO3In a chromatography column of (1). Spin-dry to a small amount of solvent and settle to a large amount of anhydrous methanol to remove the monomer. Filtering, drying the obtained polymer in a vacuum drying oven, and keeping the temperature at 40 ℃ for 12h to obtain the biphenyl liquid crystal polymer.
A500 mL round-bottomed flask containing 200mL of purified THF was charged with biphenyl liquid crystal polymer (3g,0.2mmol), alpha-lipoic acid (0.618g,3mmol), DMAP (0.0366g,0.3mmol) and TEA (0.07g,0.6mmol) in this order, the temperature of the mixed solution was lowered to 0 ℃ after ice-cooling, DCC (0.0618g, 0.3mmol) was added thereto, the mixture was stirred for 3 hours, and the reaction was continued at room temperature for 24 hours. And (4) tracking the reaction progress by a point plate, and filtering the precipitate of the mixed solution after the reaction is finished. After spin-drying of the solvent, a yellow crude product was obtained. And dissolving the crude product in a small amount of THF, settling into a large amount of anhydrous methanol, centrifuging, and then placing a sample into a vacuum drying oven, and keeping the temperature at 40 ℃ for 24 hours to obtain the target high-molecular ligand containing biphenyl liquid crystal elements. Wherein the structural formula of the obtained liquid crystal polymer ligand is as follows:
Figure BDA0001816451460000061
wherein
Figure BDA0001816451460000062
Represents
Figure BDA0001816451460000063
Pipetting HAuCl with pipette4·3H2An aqueous O solution (0.50mL,30mmol/L,0.015mmol) and a TOAB toluene solution (2mL,50mmol/L,0.1mmol) were placed in a 100mL round bottom flask and stirred vigorously at room temperature until the lower aqueous layer was colorless. After phase separation, biphenyl liquid crystalline polymer ligand (225mg,0.015 mmol) was added. Stirring for 30min, adding NaBH4An aqueous solution (0.50mL,0.40mol/L,0.20mmol) was slowly added dropwise to the organic phase. After further stirring for 3H, the organic phase is separated off and washed with H2O wash 2 times. Spin dry to leave 1mL of solvent, and settle into 200mL of absolute ethanol. Keeping at-10 deg.C for 12 hr, ultrasonic treating, and centrifuging. And repeating the steps of sedimentation, ultrasonic treatment and centrifugation until no biphenyl liquid crystal polymer ligand (dot plate) exists in the supernatant. And (3) placing the obtained product in a vacuum drying oven at 40 ℃ and keeping the constant temperature for 24 hours to obtain the biphenyl liquid crystal polymer ligand modified gold nanoparticles.
Dissolving gold nanoparticles modified by biphenyl liquid crystal polymers in toluene by mass fraction of 1%, spin-coating on a cover glass to obtain a liquid crystal polymer nanoparticle film, and annealing. Then, two annealed cover glass containing liquid crystal polymer nano particles are used for preparing a liquid crystal box for later use.
(2) Preparation of liquid Crystal elastomer films
Dissolving 4- (6-acryloyloxyhexyloxy) -4' -cyanobiphenyl, 1, 4-bis- [4- (6-acryloyloxyhexyloxy) benzoyloxy ] -2-methylbenzene and 2, 2-dimethoxy-2-phenyl acetophenone respectively serving as a liquid crystal monomer, a crosslinking agent and a photoinitiator (the molar ratio is 90:10:2.5) in dichloromethane, performing ultrasonic treatment, and naturally volatilizing a dry solvent at room temperature to obtain a mixture.
Placing the mixture and the liquid crystal box prepared in the step (1) on a hot bench, heating to the temperature of the clearing point of the mixture (above 100 ℃), and sucking the mixture into the liquid crystal box by utilizing a capillary effect. Then, the temperature was decreased to 60 ℃ at a rate of 1 ℃/min (i.e., the liquid crystal phase interval of the mixture), and it was observed by a polarizing microscope (POM) that the visual field was dark in the nematic phase temperature interval of the mixture and the dark cross extinction phenomenon was observed under cone light. Thus, it can be concluded that the mixture is vertically aligned within the cell. As shown in fig. 2 (upper right angle is conoscopic).
And (3) irradiating the liquid crystal box sucked into the mixture for 20min by using ultraviolet light at 60 ℃ to perform in-situ photopolymerization, etching the cover glass by using hydrofluoric acid, washing the film by using water to remove the hydrofluoric acid, and drying to obtain the liquid crystal elastomer film. The oriented structure of the film is characterized by two-dimensional wide-angle X-ray diffraction (2D WXRD), the incident direction of X-rays is perpendicular to the thickness direction of the film, as shown in figure 3, two diffraction arcs can be observed in a wide-angle area, which shows that liquid crystal elements are arranged along the thickness direction of the film, and the liquid crystal elastomer film with single domain orientation is obtained.
(3) Thermotropic deformation of liquid crystal elastomers
As shown in FIG. 3, when the liquid crystal elastomer film was heated to an isotropic temperature of 130 ℃ both sides of the film were rolled up, and when cooled to room temperature, the film was restored to its original shape. This reversible change in shape indicates that the liquid crystalline elastomer film has a particular reversible change in shape.
Example 2
A method for preparing a single-domain oriented liquid crystal elastomer by using gold nanoparticles modified by biphenyl azo liquid crystal macromolecules comprises the following steps:
raw materials: 4- (6-acryloyloxyhexyloxy) -4' -cyanobiphenyl, 1, 4-bis- [4- (6-acryloyloxyhexyloxy) benzoyloxy]-2-methylbenzene, 2, 2-dimethoxy-2-phenylacetophenone, ethylene glycol, 2-bromo-2-methylpropanoyl bromide, triethylamine, pentamethyldiethylenetriamine, cuprous bromide, alpha-lipoic acid, tetrachloroauric acid trihydrate, tetraoctylammonium bromide, sodium borohydride, 4-dimethylaminopyridine, Tetrahydrofuran (THF), toluene, alumina (Al)2O3)。
(1) Synthesis of biphenyl azo liquid crystal polymer modified gold nanoparticles and preparation of liquid crystal box
Liquid crystal monomer: 6- [ 4' - (4-phenoxy) p-butylazobiphenyl ] hexyl methacrylate
Catalyst: cuprous bromide (CuBr)
Initiator: isobromobutyric acid Hydroxyethyl Ester (HEBI)
Ligand: pentamethyldiethylenetriamine (PMDETA)
A small magneton, a monomer, PMDETA, CuBr and HEBI (molar charge ratio is n: 1: 1: 1, wherein n is the polymerization degree of a target polymer, and n is 50) are put into a clean polymerized glass tube in sequence. Then, purified chlorobenzene was added as a solvent, and the reaction concentration was adjusted to 30%. After freezing, vacuumizing and nitrogen blowing for more than three times, vacuum sealing the tube, placing the tube in a constant-temperature oil bath at 75 ℃, reacting for 6 hours at constant temperature, taking out the polymerization tube, placing the tube in an ice-water bath, and stopping the polymerization reaction. The polymerization tube was carefully knocked open, the polymer solution was diluted with chlorobenzene solution and added dropwise to the solution containing AlO3In a chromatography column of (1). Spin-dry to a small amount of solvent and settle to a large amount of anhydrous methanol to remove the monomer. Filtering, drying the obtained polymer in a vacuum drying oven, and keeping the temperature at 40 ℃ for 12h to obtain the biphenyl azo liquid crystal polymer.
A500 mL round-bottomed flask containing 200mL of purified THF was charged with biphenyl azo liquid crystal polymer (3g,0.2mmol), alpha-lipoic acid (0.618g,3mmol), DMAP (0.0366g,0.3mmol), TEA (0.07g,0.6mmol) in this order, the temperature of the mixed solution was lowered to 0 ℃ after ice-cooling, DCC (0.0618g, 0.3mmol) was added thereto, the mixture was stirred for 3 hours, and the reaction was continued at room temperature for 24 hours. And (4) tracking the reaction progress by a point plate, and filtering the precipitate of the mixed solution after the reaction is finished. After spin-drying of the solvent, a yellow crude product was obtained. And dissolving the crude product in a small amount of THF, settling into a large amount of anhydrous methanol, centrifuging, and then placing a sample into a vacuum drying oven, and keeping the temperature at 40 ℃ for 24 hours to obtain the target high-molecular ligand containing biphenyl azo mesogen. Wherein the structural formula of the obtained liquid crystal polymer ligand is as follows:
Figure BDA0001816451460000091
wherein
Figure BDA0001816451460000092
Represents
Figure BDA0001816451460000093
Pipetting HAuCl with pipette4·3H2An aqueous O solution (0.50mL,30mmol/L,0.015mmol) and a TOAB toluene solution (2mL,50mmol/L,0.1mmol) were placed in a 100mL round bottom flask and stirred vigorously at room temperature until the lower aqueous layer was colorless. After phase separation, biphenyl azo liquid crystalline polymer ligand (225mg,0.015 mmol) was added. Stirring for 30min, adding NaBH4An aqueous solution (0.50mL,0.40mol/L,0.20mmol) was slowly added dropwise to the organic phase. After further stirring for 3H, the organic phase is separated off and washed with H2O wash 2 times. Spin dry to leave 1mL of solvent, and settle into 200mL of absolute ethanol. Keeping at-10 deg.C for 12h, ultrasonic treating, and centrifuging. The sedimentation-ultrasonic-centrifugation steps are repeated until no biphenyl azo liquid crystal polymer ligand (dot plate) is present in the supernatant. And (3) placing the obtained product in a vacuum drying oven at 40 ℃ and keeping the constant temperature for 24 hours to obtain the biphenyl azo liquid crystal polymer ligand modified gold nanoparticles.
Dissolving gold nanoparticles modified by biphenyl azo liquid crystal polymers in toluene by mass fraction of 1%, spin-coating on a cover glass to obtain a liquid crystal polymer nanoparticle film, and annealing. Then, two annealed cover glass containing liquid crystal polymer nano particles are used for preparing a liquid crystal box for later use.
(2) Preparation of a Single-Domain liquid Crystal elastomer film
Dissolving 4- (6-acryloyloxyhexyloxy) -4' -cyanobiphenyl, 1, 4-bis- [4- (6-acryloyloxyhexyloxy) benzoyloxy ] -2-methylbenzene and 2, 2-dimethoxy-2-phenyl acetophenone respectively serving as a liquid crystal monomer, a crosslinking agent and a photoinitiator (the molar ratio is 90:10:2.5) in dichloromethane, performing ultrasonic treatment, and naturally volatilizing a dry solvent at room temperature to obtain a mixture.
Placing the mixture and the liquid crystal box prepared in the step (1) on a hot bench, heating to the temperature of the clearing point of the mixture (above 100 ℃), and sucking the mixture into the liquid crystal box by utilizing a capillary effect. Then, the temperature was decreased to 60 ℃ at a rate of 1 ℃/min (i.e., the liquid crystal phase interval of the mixture), and it was observed by a polarizing microscope (POM) that the visual field was dark in the nematic phase temperature interval of the mixture and the dark cross extinction phenomenon was observed under cone light. Thus, it can be concluded that the mixture is vertically aligned within the cell.
And (3) irradiating the liquid crystal box sucked into the mixture for 20min by using ultraviolet light at 60 ℃ to perform in-situ photopolymerization, etching the cover glass by using hydrofluoric acid, washing the film by using water to remove the hydrofluoric acid, and drying to obtain the liquid crystal elastomer film. The oriented structure of the film is characterized by two-dimensional wide-angle X-ray diffraction (2D WXRD), the incident direction of X-rays is perpendicular to the thickness direction of the film, two diffraction arcs can be observed in a wide-angle area, and the liquid crystal elements are shown to be arranged along the thickness direction of the film, so that the liquid crystal elastomer film with single-domain orientation is obtained.
(3) Thermotropic deformation of liquid crystal elastomers
When the liquid crystalline elastomer film was heated to an isotropic temperature of 130 c, both sides of the film rolled up, and when cooled to room temperature, the film returned to its original shape. This reversible change in shape indicates that the liquid crystalline elastomer film has a particular reversible change in shape.

Claims (5)

1. A method for constructing a single-domain liquid crystal elastomer by using liquid crystal polymer modified nano particles comprises the following steps:
(1) preparing liquid crystal polymer modified nano particles, dissolving the obtained liquid crystal polymer modified nano particles in an organic solvent, then spin-coating on a cover glass, and annealing to prepare a liquid crystal box;
(2) blending a liquid crystal monomer, a cross-linking agent and an initiator, dissolving in an organic solvent, and forming a uniform liquid crystal mixture after the solvent is volatilized;
(3) sucking the obtained liquid crystal mixture into a liquid crystal box, annealing, carrying out in-situ polymerization, crosslinking a liquid crystal monomer to form a liquid crystal elastomer, and removing a glass substrate to obtain a single-domain oriented liquid crystal elastomer film;
the structure of the liquid crystal polymer modified nano particle in the step (1) is shown as a formula I:
Figure FDA0003195261170000011
in the formula I, M is one of gold nanoparticles, nickel nanoparticles, carbon nanotubes and polyhedral oligomeric silsesquioxane (POSS); in the formula I, N is one of sulfur, alkyl, alkoxy, ester group and carbonyl; in the formula I, n is more than or equal to 30, A is one of alkyl, alkoxy, ester group and carbonyl; in the formula I, B is one of hydrogen, alkyl or alkoxy; in the formula I, C is one of the formulas II:
Figure FDA0003195261170000012
in the formula II, wherein R1Is (CH)2)n，(CH2)nO, and n is more than or equal to 0 and less than or equal to 18; wherein R is2Is H, (CH)2)nCH3，O(CH2)nCH3，NH(CH2)nCH3，CN，NO2，SO3One of Na, and n is more than or equal to 0 and less than or equal to 18;
the molecular structure of the liquid crystal monomer in the step (2) is shown as a formula III:
Figure FDA0003195261170000021
in the formula III, wherein R1Is (CH)2)nAnd n is more than or equal to 0 and less than or equal to 10; wherein R is2Is (CH)2)n，(CH2)nO, and n is more than or equal to 0 and less than or equal to 10;
the molecular structure of the cross-linking agent in the step (2) is shown as a formula IV:
Figure FDA0003195261170000022
in the formula IV, wherein R3Is (CH)2)nAnd n is more than or equal to 0 and less than or equal to 10; wherein R is4Is H, CH3One kind of (1); the initiator in the step (2) is one of a thermal initiator and a photoinitiator; wherein the photoinitiator is one of 2, 2-dimethoxy-2-phenyl acetophenone, methyl o-benzoylbenzoate and 2-hydroxy-2-methylphenyl propane-1-ketone; wherein the thermal initiator is one of azodiisobutyronitrile, azodiisoheptonitrile and dibenzoyl peroxide.
2. The method for preparing a monodomain liquid crystalline elastomer from liquid crystal polymer-modified nanoparticles as claimed in claim 1, wherein the organic solvent used in the step (2) is one of dichloromethane, chloroform and acetone.
3. The method for preparing a monodomain liquid crystalline elastomer from nanoparticles modified with a liquid crystalline polymer as claimed in claim 1, wherein the temperature at which the mixture is drawn into the liquid crystal cell in step (3) is higher than the isotropic temperature of the mixture.
4. The method for preparing a monodomain liquid crystal elastomer from nanoparticles modified by a liquid crystal polymer as claimed in claim 1, wherein the in-situ polymerization in the step (3) is one of photo-initiated polymerization and thermal initiated polymerization.
5. The method for preparing a monodomain liquid crystal elastomer from nanoparticles modified by liquid crystal polymers as claimed in claim 1, wherein the step (3) is performed by etching a cover glass with a hydrofluoric acid solution to obtain a liquid crystal elastomer film.
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* Cited by examiner, † Cited by third party
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CN104449542A (en) * 2014-12-11 2015-03-25 江南大学 Preparation method of novel dual-cured UV curing binder
CN104529781A (en) * 2014-11-14 2015-04-22 泰州市产品质量监督检验所 A synthetic method of a chiral liquid crystal monomer, a cross-linking agent and an elastomer of the monomer
CN107121844A (en) * 2017-05-23 2017-09-01 湘潭大学 The method that the golden nanometer particle modified by liquid crystal polymer regulates and controls liquid crystal aligning

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JP5827161B2 (en) * 2012-03-28 2015-12-02 富士フイルム株式会社 Cholesteric liquid crystalline mixture, film, infrared reflector, laminate and laminated glass

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104529781A (en) * 2014-11-14 2015-04-22 泰州市产品质量监督检验所 A synthetic method of a chiral liquid crystal monomer, a cross-linking agent and an elastomer of the monomer
CN104449542A (en) * 2014-12-11 2015-03-25 江南大学 Preparation method of novel dual-cured UV curing binder
CN107121844A (en) * 2017-05-23 2017-09-01 湘潭大学 The method that the golden nanometer particle modified by liquid crystal polymer regulates and controls liquid crystal aligning

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