CN109280556B - Method for preparing polymer dispersed liquid crystal film based on epoxy step-by-step thermosetting - Google Patents
Method for preparing polymer dispersed liquid crystal film based on epoxy step-by-step thermosetting Download PDFInfo
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Abstract
The invention relates to the technical field of liquid crystal material application, in particular to a method for preparing a polymer dispersed liquid crystal film based on epoxy step-by-step thermosetting, which comprises the following steps of 1) uniformly mixing a non-liquid crystal epoxy monomer, a thiol monomer, liquid crystal and an accelerator in proportion, pouring the mixture into a liquid crystal box to obtain a sample, 2) carrying out primary thermosetting on the sample obtained in the step 1), and 3) carrying out secondary thermosetting on the sample obtained in the step 2), namely applying an electric field to the sample, and continuously curing to obtain a film of a polymer stabilized liquid crystal and polymer dispersed liquid crystal coexisting system, wherein an epoxy/thiol polymer obtained after curing has better adhesive force, stability and mechanical property, and is favorable for improving the practical value of PD L C.
Description
Technical Field
The invention relates to the technical field of liquid crystal material application, in particular to a method for preparing a polymer dispersed liquid crystal film based on epoxy step-by-step thermosetting. The method can be used for regulating and controlling the electro-optic performance of the thermosetting polymer dispersed liquid crystal, thereby providing a feasible way for preparing the polymer dispersed liquid crystal film with low driving voltage.
Background
A Polymer Dispersed liquid Crystal film (Polymer Dispersed L i liquid Crystal, hereinafter referred to as PD L C) is an important liquid Crystal/Polymer composite material, and due to the special electro-optical properties of liquid crystals, the transmittance of the film can be controlled by an external electric field, so that the change between a light scattering state and a light transmission state can be realized.
Generally, in order to consider the electricity safety of users, the saturation voltage of PD L C should not exceed 36V, in order to reduce the saturation voltage of PD L C, in the past, many researches are focused on doping nano materials, doping surfactants, improving the dielectric property of liquid crystal and the like.
Compared with other preparation processes, the epoxy thermosetting method has the advantages that monomers used by the thermosetting method are low in volatility and toxicity, meanwhile, the obtained polymer network has low shrinkage rate, and the yellowing problem of a thin film hardly exists.
Disclosure of Invention
The invention aims to provide a method for preparing a polymer dispersed liquid crystal film based on epoxy stepwise thermosetting, which can be used for regulating and controlling the electro-optical performance of thermosetting polymer dispersed liquid crystal, thereby providing a feasible way for preparing a polymer dispersed liquid crystal film with low driving voltage. The preparation method utilizes the activity difference of the non-liquid crystal epoxy monomer and the liquid crystal epoxy monomer, and thermal polymerization is carried out at a certain temperature, so that most of non-liquid crystal epoxy and the mercaptan monomer are firstly cured to form a polymer matrix of polymer dispersed liquid crystal. Due to the small curing activity of the liquid crystalline epoxy monomer, a certain amount of liquid crystalline polymerized monomers still exist in the system after pre-curing. By applying an electric field with a certain intensity, the liquid crystalline epoxy monomer can be aligned with the liquid crystal under the electric field with a certain degree of order. By continuing the long-term curing, these residual non-liquid crystal epoxy monomers can be allowed to form a liquid crystal epoxy network having a certain alignment structure by reaction with a mercapto group. The liquid crystalline epoxy network having a certain orientation can form a certain degree of order in the liquid crystal in the vicinity thereof, so that the energy required for the complete homeotropic orientation of the liquid crystal can be reduced, and thus the effect of reducing the driving voltage of the polymer dispersed liquid crystal can be achieved.
The specific technical scheme of the invention is as follows:
the invention provides a method for preparing a polymer dispersed liquid crystal film based on epoxy stepwise thermosetting, which comprises the following steps:
1) uniformly mixing a non-liquid crystal epoxy monomer, a mercaptan monomer, liquid crystal and an accelerator in proportion, and pouring the mixture into a liquid crystal box to obtain a sample;
2) carrying out primary heat curing on the sample obtained in the step 1);
3) carrying out secondary heat curing on the sample obtained in the step 2): and applying an electric field to the sample, and continuously curing to obtain the film of the polymer stable liquid crystal and polymer dispersed liquid crystal coexisting system.
The non-liquid crystal epoxy monomer accounts for 13.6-21.7% of the total mass of the system, the liquid crystal epoxy monomer accounts for 0-6% of the total mass of the system, the mercaptan monomer accounts for 24.4-38.3% of the total mass of the system, the liquid crystal monomer accounts for 38.0-59.0% of the total mass of the system, and the accelerator accounts for 1.0-2.0% of the total mass of the system.
Preferably, the non-liquid crystal epoxy monomer includes a three-membered epoxy compound 4- (2, 3-epoxypropoxy) -N, N-bis (2, 3-epoxypropyl) aniline, a two-membered epoxy compound polypropylene glycol diepoxyethylene methyl ether and bisphenol a epoxy resin E44.
Preferably, the liquid crystalline epoxy monomer is E6M, and the structure thereof is shown in fig. 1.
Preferably, the thiol monomer is polythiol Capcure3800 having a thiol value of 280 g/mol.
Preferably, the liquid crystal is nematic liquid crystal E8.
Preferably, the accelerator is 2,4, 6-tris (dimethylaminomethyl) phenol.
Preferably, the thickness of the liquid crystal cell is controlled to be 19.0 ± 1.0 μm.
Preferably, the liquid crystal cell in step 1) is made of two pieces of conductive glass coated with indium tin oxide.
Preferably, the sample curing temperature in the step 2) is 313.15K-353.15K, and the sample curing time is 1.0-24.0 h.
Preferably, the sample curing applied electric field intensity in the step 3) is 0V-100V.
Preferably, the sample curing temperature in the step 3) is 313.15K to 353.15K, and the sample curing time is 2-7 d.
The method for preparing the polymer dispersed liquid crystal film based on epoxy step-by-step thermosetting comprises the following specific processes:
the preparation of the film is divided into two processes of primary heat curing and secondary heat curing. Firstly, the sample is subjected to primary heat curing, specifically: the sample is cured at a temperature and for a time to allow the non-liquid crystal monomer and the thiol monomer to polymerize to form the polymer matrix of the polymer dispersed liquid crystal film. Then, the sample was subjected to a second heat curing, specifically: and applying an electric field with certain intensity to the sample, and continuously curing the sample under the electric field to ensure that the residual liquid crystal epoxy monomer continuously reacts with the redundant sulfydryl at the interface of the polymer matrix formed by pre-curing, so that a secondary network can be formed in a liquid crystal area, and the film of the polymer stable liquid crystal and polymer dispersed liquid crystal coexisting system is prepared.
Compared with the prior art, the invention has the advantages that:
the method is simple and convenient, is suitable for commercial production, and the selected curing monomer is low in price, has no volatility and low toxicity, and the epoxy/mercaptan polymer obtained after curing has good adhesive force, stability and mechanical property, and is beneficial to improving the practical value of PD L C.
Drawings
FIG. 1 shows the structural formula of the monomer and accelerator used in the present invention, and the relevant parameters of liquid crystal E8;
FIG. 2 shows the results of the electro-optical properties of polymer dispersed liquid crystal films prepared in examples 1 to 3 of the present invention;
FIG. 3 shows the results of the electro-optical properties of polymer dispersed liquid crystal films prepared in examples 4 to 6 of the present invention;
FIG. 4 shows the results of the electro-optical properties of polymer dispersed liquid crystal films prepared in examples 7 to 8 of the present invention;
FIG. 5 shows the results of the electro-optical properties of the polymer dispersed liquid crystal films prepared in examples 9 to 10 of the present invention;
FIG. 6 shows the results of the electro-optical properties test of the polymer dispersed liquid crystal film prepared in example 11 of the present invention;
FIG. 7 shows the results of the electro-optical properties test of the polymer dispersed liquid crystal film prepared in example 12 of the present invention;
FIG. 8 shows the results of the electro-optical properties test of the polymer dispersed liquid crystal film prepared in example 13 of the present invention;
FIG. 9 is an experimental schematic diagram of the present invention.
Detailed Description
The present invention will be further described with reference to the following specific examples.
In the invention, the percentages are mass percentages, the temperatures are absolute temperatures, and the symbols represent the following meanings:
Toffrepresents the light transmittance, T, in the off state of PD L ConRepresents the light transmittance, V, of PD L C under the application of 100V electric fieldthIndicating the threshold voltage means that when the light transmittance of PD L C reaches Ton10% of the required voltage, VsatThe expression of saturation voltage means that when the light transmittance of PD L C reaches Ton90% of the required voltage. CR represents contrast, and is calculated by: CR ═ Ton/Toff。
Example 1
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 1, and is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide after being fully stirred uniformly, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film can be obtained after two steps of curing.
Table 1 composition of the samples in example 1
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 2.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 1 are shown in table 2.
TABLE 2 Main electro-optical Properties of Polymer dispersed liquid Crystal film prepared in example 1
Example 2
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 3, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
Table 3 composition of the samples in example 2
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 2.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 2 are shown in table 4.
TABLE 4 Main electro-optical Properties of Polymer dispersed liquid Crystal film prepared in example 2
Example 3
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 5, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
Table 5 composition of the samples in example 3
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 2.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 3 are shown in table 6.
TABLE 6 Main electro-optical Properties of Polymer dispersed liquid Crystal film prepared in example 3
From the analysis of the results obtained in examples 1-3, it can be seen that the driving voltage of the PD L C film can be reduced by the two-time curing method after the liquid crystalline epoxy monomer is added into the system, however, if the content of the liquid crystalline epoxy monomer is too high, the anchoring effect of the liquid crystalline epoxy network formed by the two-time thermal curing on the liquid crystal is too large, so that the liquid crystal molecules adjacent to the liquid crystalline epoxy network still have a certain orientation in the off state, which results in too high off-state transmittance and reduced contrast of the PD L C film, therefore, in order to obtain a PD L C film with more practical value, the content of the liquid crystalline epoxy monomer needs to be reasonably controlled, and preferably, in example 2, the content of the liquid crystalline epoxy monomer is 1.5%, and the driving voltage is much lower than that of the sample in example 1, and a certain contrast can be maintained.
Example 4
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, then a 0V external electric field is applied to the sample, and the sample is continuously cured for 48h, and then after two steps of curing, a PD L C film can be obtained.
TABLE 7 compositions of samples from examples 4-10
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 3.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 4 are shown in table 8.
TABLE 8 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 4
Example 5
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, then an external electric field of 30V is applied to the sample, and the sample is continuously cured for 48h, and then after two-step curing, the PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 3.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 5 are shown in table 9.
TABLE 9 Primary electrooptical Properties of Polymer dispersed liquid Crystal films prepared in example 5
Example 6
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 3.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 6 are shown in table 10.
TABLE 10 Primary electrooptical Properties of Polymer dispersed liquid Crystal films prepared in example 6
From the analysis of the results of examples 4-6, it can be seen that PD L C films with different properties can be obtained by adjusting the strength of the applied electric field during the secondary thermal curing.
Example 7
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot table and cured for 1.0h at 313.15K, then an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 4.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 7 are shown in table 11.
TABLE 11 Main electro-optical Properties of Polymer dispersed liquid Crystal film prepared in example 7
Example 8
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 353.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 4.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 8 are shown in table 12.
TABLE 12 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 8
From the analysis of the results of examples 6 to 8, it can be seen that the temperature of the primary thermal curing is also an important factor affecting the performance of the PD L C film.
Example 9
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot table and cured for 1.5h at 313.15K, then an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 5.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 9 are shown in table 13.
TABLE 13 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 9
Example 10
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after the mixture is fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot table and cured for 24.0h at 353.15K, then an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, and after two-step curing, the PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 5.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 10 are shown in table 14.
TABLE 14 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 10
From the analysis of the results of examples 6, 9 and 10, it can be seen that the time of the primary thermal curing is also an important factor affecting the performance of the PD L C film.
Example 11
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 15, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, then an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, and then after two steps of curing, a PD L C film can be obtained.
TABLE 15 composition of samples from example 11
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 6.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 4 are shown in table 16.
TABLE 16 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 11
Example 12
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 7, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 148h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained.
The electro-optical performance curve of the PD L C film prepared above was measured by a liquid crystal comprehensive parameter tester, as shown in FIG. 7.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 12 are shown in table 17.
TABLE 17 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 12
Example 13
NDGA/E44/PGDE/E6M/Capcure 3800/E8/DMP-30 is mixed according to the mass fraction ratio of Table 18, and after being fully stirred uniformly, the mixture is poured into a liquid crystal box made of two pieces of conductive glass plated with indium tin oxide, the thickness of the liquid crystal box is controlled to be 20.0 um., a sample is firstly placed on a hot bench and cured for 1.0h at 333.15K, an external electric field of 100V is applied to the sample, and the sample is continuously cured for 48h, so that a PD L C film of a polymer dispersed liquid crystal and polymer stable liquid crystal coexisting system can be obtained after two-step curing.
TABLE 18 composition of samples from example 13
The electro-optical performance curve of the PD L C film prepared above was measured with a liquid crystal comprehensive parameter tester, as shown in fig. 8.
The main electro-optical properties of the polymer dispersed liquid crystal film prepared by example 12 are shown in table 19.
TABLE 19 Primary electrooptical Properties of Polymer dispersed liquid Crystal film prepared in example 13
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (9)
1. A method for preparing a polymer dispersed liquid crystal film based on epoxy stepwise thermal curing comprises the following steps:
1) uniformly mixing a non-liquid crystal epoxy monomer, a mercaptan monomer, liquid crystal and an accelerator in proportion, and pouring the mixture into a liquid crystal box to obtain a sample;
2) carrying out primary heat curing on the sample obtained in the step 1);
3) carrying out secondary heat curing on the sample obtained in the step 2): applying an electric field to the sample, and continuously curing to obtain a film of a polymer stable liquid crystal and polymer dispersed liquid crystal coexisting system;
the non-liquid crystal epoxy monomer accounts for 13.6-21.7% of the total mass of the system, the liquid crystal epoxy monomer accounts for 1.5-6% of the total mass of the system, the mercaptan monomer accounts for 24.4-38.3% of the total mass of the system, the liquid crystal monomer accounts for 38.0-59.0% of the total mass of the system, and the accelerator accounts for 1.0-2.0% of the total mass of the system.
2. The method according to claim 1, wherein the non-liquid crystal epoxy monomer comprises one or more of a three-membered epoxy compound, 4- (2, 3-epoxypropoxy) -N, N-bis (2, 3-epoxypropyl) aniline, a two-membered epoxy compound, polypropylene glycol diepoxide ethylene methyl ether, and bisphenol a epoxy resin E44;
wherein the chemical formula of the bisphenol A epoxy resin E44 is
3. The method according to claim 1, wherein the liquid crystalline epoxy monomer is E6M;
wherein E6M has the formula
4. The method of claim 1, wherein the thiol monomer is a polythiol, Capcure 3800.
5. The method according to claim 1, wherein the accelerator is 2,4, 6-tris (dimethylaminomethyl) phenol.
6. The production method according to claim 1, wherein the thickness of the liquid crystal cell is controlled to 19.0 ± 1.0 μm.
7. The method according to claim 1, wherein the liquid crystal cell of step 1) is made of two pieces of conductive glass coated with indium tin oxide.
8. The preparation method of claim 1, wherein the sample curing temperature in the step 2) is 313.15K to 353.15K, and the sample curing time is 1.0 to 24.0 h.
9. The preparation method of claim 1, wherein the sample curing applied electric field intensity in the step 3) is 30V-100V, the sample curing temperature is 313.15K-353.15K, and the sample curing time is 2-7 d.
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| CN111454736B (en) * | 2020-04-27 | 2022-02-22 | Tcl华星光电技术有限公司 | Circular polarization modulation device and preparation method thereof |
| CN111736377B (en) * | 2020-06-17 | 2022-04-26 | 深圳市华星光电半导体显示技术有限公司 | Liquid crystal layer, preparation method thereof and liquid crystal display device |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1421506A (en) * | 2002-12-06 | 2003-06-04 | 华东理工大学 | Prepn process of dispersed polymer liquid crystal material |
| CN102321233A (en) * | 2011-06-23 | 2012-01-18 | 北京科技大学 | Preparation method of epoxy resin-based polymer dispersion liquid crystal film material |
| CN102516498A (en) * | 2011-12-06 | 2012-06-27 | 北京科技大学 | Preparation method of polymer mixed network-based polymer dispersed liquid crystal (PDLC) film material |
| CN106324883A (en) * | 2015-07-03 | 2017-01-11 | 北京大学 | Method for preparing cholesteric liquid crystal functional film through ultraviolet light-heating two-step polymerization |
| CN106338854A (en) * | 2015-07-07 | 2017-01-18 | 北京大学 | Method for preparing Cholesteric liquid crystal functional film using heating-ultraviolet light step-by-step polymerization method |
| CN106336875A (en) * | 2015-07-07 | 2017-01-18 | 北京大学 | Preparation method of trans polymer-dispersed liquid crystal film |
-
2018
- 2018-10-26 CN CN201811258942.4A patent/CN109280556B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1421506A (en) * | 2002-12-06 | 2003-06-04 | 华东理工大学 | Prepn process of dispersed polymer liquid crystal material |
| CN102321233A (en) * | 2011-06-23 | 2012-01-18 | 北京科技大学 | Preparation method of epoxy resin-based polymer dispersion liquid crystal film material |
| CN102516498A (en) * | 2011-12-06 | 2012-06-27 | 北京科技大学 | Preparation method of polymer mixed network-based polymer dispersed liquid crystal (PDLC) film material |
| CN106324883A (en) * | 2015-07-03 | 2017-01-11 | 北京大学 | Method for preparing cholesteric liquid crystal functional film through ultraviolet light-heating two-step polymerization |
| CN106338854A (en) * | 2015-07-07 | 2017-01-18 | 北京大学 | Method for preparing Cholesteric liquid crystal functional film using heating-ultraviolet light step-by-step polymerization method |
| CN106336875A (en) * | 2015-07-07 | 2017-01-18 | 北京大学 | Preparation method of trans polymer-dispersed liquid crystal film |
Non-Patent Citations (1)
| Title |
|---|
| An electrically light-transmittance-controllable film with a low-driving voltage from a coexistent system of polymer-dispersed and polymer-stabilised cholesteric liquid crystals;Guo, Shumeng;《Liquid Crystals》;20180722;第45卷(第12期);1854-1860 * |
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