Fluorine-containing resin, photopolymer type holographic recording medium as well as preparation method and application of photopolymer type holographic recording medium

Abstract

The invention provides fluorine-containing resin, a photopolymer type holographic recording medium and a preparation method and application of the photopolymer type holographic recording medium, the fluorine-containing resin has a structure shown as G1 or G2, the fluorine-containing resin has a low refractive index (refractive index lt: 1.35), the compatibility of film-forming resin and recording monomers is effectively improved, and the production cost of the material is remarkably reduced. The recording monomer is used in cooperation with a high-refractive-index monomer (the refractive index is larger than 1.55), and the refractive index difference between the recording monomer and the film-forming resin is increased to 0.25 or above. The sensitivity of the holographic recording medium is greater than 100 cm / mJ, the diffraction efficiency of the recording grating is greater than 95%, the refractive index modulation degree is greater than 0.1, and the haze is lower than 1%.

Description

Technical Field

[0001] This application belongs to the field of optical functional materials technology, and relates to a fluorinated resin, a photopolymer type holographic recording medium, its preparation method and application. Background Technology

[0002] Photopolymer materials used for holographic recording mainly include photosensitive dyes, initiators, chain transfer agents, recording monomers, film-forming resins, and plasticizers. Holographic recording is achieved by using light to polymerize the monomers, which then combine with the film-forming resin to form a phase-type holographic grating with refractive index modulation. In the coherent bright region, monomer polymerization consumes and reduces concentration, while in the coherent dark region, monomers hardly react. The difference in monomer concentration between the bright and dark regions causes monomers in the dark region to migrate towards the bright region. Simultaneously, the film-forming resin in the bright region is squeezed into the dark region. Ultimately, the refractive index of the bright region approaches the refractive index of the polymer, and the refractive index of the dark region approaches the refractive index of the film-forming resin, thus forming a phase-type volume holographic grating with refractive index modulation.

[0003] Improving the performance of photopolymers generally requires a lower refractive index for the base resin and a higher refractive index for the recording monomer. However, the refractive index of film-forming resins is typically around 1.45, while the refractive index of recording monomers is usually greater than 1.55. This results in a small refractive index difference between the recording monomer and the film-forming resin (typically ~0.1), leading to low holographic recording performance of the photopolymer. Increasing the refractive index difference between the two is beneficial for achieving higher performance in photopolymers. However, a high refractive index difference can cause the recording monomer to separate from the film-forming resin after polymerization, thus increasing sample haze. Using a resin with a high fluorine content as the film-forming resin can effectively reduce the refractive index of the film-forming resin, thereby obtaining a high refractive index difference between the film-forming resin and the recording monomer. However, excessively high fluorine content can lead to a large structural difference between the film-forming resin and the recording monomer. Therefore, after the photopolymer is prepared, the film-forming resin may separate from the recording monomer during storage, resulting in the loss of holographic recording performance. In addition, excessive structural differences can also cause the polymer formed by the polymerization of the recording monomer to separate from the film-forming resin during holographic recording, resulting in high haze of the recording grating.

[0004] Therefore, the above-mentioned problems urgently need to be addressed by those skilled in the art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a fluoropolymer-containing resin, a photopolymer-type holographic recording medium, its preparation method, and its application.

[0006] To achieve this objective, the present application adopts the following technical solution:

[0007] In a first aspect, this application provides a fluorinated resin having the structure shown in G1 or G2 below:

[0008]

[0009] ;

[0010] Where x is an integer from 100 to 200, y is an integer from 20 to 400, z is an integer from 100 to 2000, a is an integer from 10 to 150, b is an integer from 10 to 150, n is an integer from 1 to 9, R1 represents hydrogen or methyl, and R2 represents a straight-chain alkyl or branched-chain alkyl from C1 to C12, or a cycloalkyl from C3 to C12.

[0011] In this application, the fluorinated resin is a random copolymer containing fluorine (F) atoms in its structure. It contains both F-containing and F-free structural segments. The F-containing segment results in a lower refractive index, increasing the refractive index difference between the resin and the high-refractive-index monomer. The F-free segment improves its compatibility with the high-refractive-index monomer as a film-forming resin, avoiding the problem of resin-monomer phase separation during the early stages of photopolymer film exposure. The presence of segments with unsaturated double bonds allows it to participate in the thiol ene click reaction during holographic exposure, resulting in a covalent bond between the polymer generated by the thiol ene click reaction and the film-forming resin, effectively reducing the haze of the holographic grating.

[0012] In this application, X is an integer from 100 to 200, such as 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, or 200, etc.; y is an integer from 20 to 400, such as 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280, 300, 320, 340, 360, 380, or 400, etc.; and z is an integer from 100 to 2000, such as 100, 200, 300, 400, 500, 60, etc. 0, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 or 2000, etc., where a is an integer from 10 to 150, such as 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140 or 150, etc., where b is an integer from 10 to 150, such as 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140 or 150, etc., and n is an integer from 1 to 9, such as 1, 2, 3, 4, 5, 6, 7, 8 or 9.

[0013] In this application, C1~C12 can be C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12, and C3~C12 can be C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12.

[0014] In this application, R2 is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl, etc. Dodecyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.

[0015] In some preferred embodiments, the fluorinated resin is any one of the following resins:

[0016] .

[0017] Secondly, this application provides a method for preparing the fluorinated resin as described above, the method comprising the following steps:

[0018] (1) Synthesis of fluorinated resin G1:

[0019] S1-1, compound P1, compound P2, and trichlorofluoroethylene undergo a polymerization reaction to obtain polymer P3, as shown in the following reaction formula:

[0020] ;

[0021] S1-2 and polymer P3 undergo an elimination reaction in the presence of an alkaline substance to yield fluorinated resin G1, as shown in the following reaction formula:

[0022] ;

[0023] (2) Synthesis of fluorinated resin G1:

[0024] S2-1, compound P4, compound P2, and monochlorotrifluoroethylene undergo a polymerization reaction to obtain polymer P5, as shown in the following reaction formula:

[0025] ;

[0026] S2-2 and polymer P5 undergo an elimination reaction in the presence of an alkaline substance to yield fluorinated resin G2, as shown in the following reaction formula:

[0027] .

[0028] In some embodiments, the molar ratio of compound P1 to compound P2 in step S1-1 is (0.1-10):1, for example, 0.1:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1 or 10:1.

[0029] In some embodiments, the molar ratio of compound P1 in step S1-1 to trichlorotrifluoroethylene is 1-100:1, for example 1:1, 3:1, 5:1, 8:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1 or 100:1.

[0030] In some embodiments, the polymerization reaction described in step S1-1 is carried out under the initiation of a thermal initiator.

[0031] In some embodiments, the thermal initiator includes, but is not limited to, any one or a combination of at least two of azobisisobutyronitrile (AIBN), azobisisoheptanenitrile (ABVN), benzoyl peroxide (BPO), dicumyl peroxide (DCP), potassium persulfate (KPS), ammonium persulfate (APS), diisopropyl peroxide (IPP), dicyclohexyl peroxide (DCPD), lauroyl peroxide (LPO), tert-butyl hydroperoxide (TBHP), acetylacetone peroxide (AAPH), di-tert-butyl peroxide (DTBP), or di(4-tert-butylcyclohexyl) peroxide (TBCP).

[0032] In some embodiments, the molar ratio of the thermal initiator to compound P1 is 1:100-1000, for example 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650, 1:700, 1:750, or 1:1000, etc.

[0033] In some embodiments, the polymerization reaction described in step S1-1 is carried out in an organic solvent.

[0034] In this application, the organic solvent is a commonly used solvent in the art, including but not limited to one or a combination of at least two of petroleum ether, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide or dimethyl sulfoxide.

[0035] In this application, the thermal initiator, compound P1, compound P2 and monochlorotrifluoroethylene are dissolved in an organic solvent in an environment of -70 to -5°C (e.g., -70°C, -65°C, -60°C, -55°C, -50°C, -45°C, -40°C, -35°C, -30°C, -20°C, -10°C or -5°C, etc.).

[0036] In some embodiments, the temperature of the polymerization reaction in step S1-1 is 20~100℃ (e.g., 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃ or 100℃, etc.), and the reaction time is 1~36 h (e.g., 1h, 3h, 6h, 12h, 16h, 21h, 24h, 30h or 36h, etc.).

[0037] In some embodiments, the polymerization reaction in step S1-1 is carried out under the protection of an inert gas, preferably nitrogen.

[0038] In this application, after the polymerization reaction in step S1-1 is completed, the obtained polymer is recovered and washed with methanol, and then vacuum dried to obtain copolymer P3.

[0039] In this application, the base mentioned in steps S1-2 is a commonly used organic base in the art, including but not limited to any one or a combination of at least two of the following: triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, sodium methoxide, sodium ethoxide, or potassium tert-butoxide.

[0040] In some embodiments, the mass ratio of polymer P3 to alkaline substance in steps S1-2 is 1:0.3 to 1, for example 1:0.3, 1:0.5, 1:0.8 or 1:1.

[0041] In some embodiments, the elimination reaction described in steps S1-2 is carried out in a solvent, which is a commonly used solvent in the art, including but not limited to one or a combination of at least two of petroleum ether, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide.

[0042] In some embodiments, the elimination reaction temperature in steps S1-2 is 50~200℃ (e.g., 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃ or 200℃, etc.), and the reaction time is 3~48 h (e.g., 3h, 8h, 13h, 18h, 23h, 28h, 33h, 38h, 43h or 48h, etc.).

[0043] In some embodiments, the elimination reaction described in steps S1-2 is carried out under the protection of an inert gas, preferably nitrogen.

[0044] In some embodiments, after the elimination reaction described in steps S1-2 is completed, excess alkali is removed by precipitation with hydrochloric acid, and then the precipitate is dissolved in acetone and precipitated three times with methanol to obtain polymer G1.

[0045] In some embodiments, the molar ratio of compound P4 to compound P2 in step S2-1 is (0.1-10):1, for example, 0.1:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1 or 10:1.

[0046] In some embodiments, the molar ratio of compound P4 in step S2-1 to trichlorotrifluoroethylene is 1-100:1, for example 1:1, 3:1, 5:1, 8:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1 or 100:1.

[0047] In some embodiments, the polymerization reaction described in step S2-1 is carried out under the initiation of a thermal initiator.

[0048] In some embodiments, the thermal initiator includes, but is not limited to, any one or a combination of at least two of azobisisobutyronitrile (AIBN), azobisisoheptanenitrile (ABVN), benzoyl peroxide (BPO), dicumyl peroxide (DCP), potassium persulfate (KPS), ammonium persulfate (APS), diisopropyl peroxide (IPP), dicyclohexyl peroxide (DCPD), lauroyl peroxide (LPO), tert-butyl hydroperoxide (TBHP), acetylacetone peroxide (AAPH), di-tert-butyl peroxide (DTBP), or di(4-tert-butylcyclohexyl) peroxide (TBCP).

[0049] In some embodiments, the molar ratio of the thermal initiator to compound P4 is 1:100-1000, such as 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650, 1:700, 1:750, or 1:1000.

[0050] In some embodiments, the polymerization reaction described in step S2-1 is carried out in an organic solvent.

[0051] In this application, the organic solvent is a commonly used solvent in the art, including but not limited to one or a combination of at least two of petroleum ether, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide.

[0052] In this application, the thermal initiator, compound P4, compound P2 and monochlorotrifluoroethylene are dissolved in an organic solvent in an environment of -70 to -5°C (e.g., -70°C, -65°C, -60°C, -55°C, -50°C, -45°C, -40°C, -35°C, -30°C, -20°C, -10°C or -5°C, etc.).

[0053] In some embodiments, the polymerization reaction in step S2-1 is carried out at a temperature of 20-100°C (e.g., 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C) and for a reaction time of 1-36 h (e.g., 1 h, 3 h, 6 h, 12 h, 16 h, 21 h, 24 h, 30 h, or 36 h).

[0054] In some embodiments, the polymerization reaction in step S2-1 is carried out under the protection of an inert gas, preferably nitrogen.

[0055] In this application, after the polymerization reaction in step S2-1 is completed, the obtained polymer is recovered and washed with methanol, and then vacuum dried to obtain copolymer P5.

[0056] In this application, the base mentioned in step S2-2 is a commonly used organic base in the art, including but not limited to any one or a combination of at least two of the following: triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, sodium methoxide, sodium ethoxide or potassium tert-butoxide.

[0057] In some embodiments, the mass ratio of polymer P4 to alkaline substance in step S2-2 is 1:0.3 to 1, for example 1:0.3, 1:0.5, 1:0.8 or 1:1.

[0058] In some embodiments, the elimination reaction in step S2-2 is carried out in a solvent, which is a commonly used solvent in the art, including but not limited to one or a combination of at least two of petroleum ether, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide or dimethyl sulfoxide.

[0059] In some embodiments, the elimination reaction in step S2-2 is carried out at a temperature of 50-200°C (e.g., 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, or 200°C), and the reaction time is carried out at a temperature of 3-48 h (e.g., 3h, 8h, 13h, 18h, 23h, 28h, 33h, 38h, 43h, or 48h).

[0060] In some embodiments, the elimination reaction in step S2-2 is carried out under the protection of an inert gas, preferably nitrogen.

[0061] In some embodiments, after the elimination reaction described in step S2-2 is completed, excess alkali is removed by precipitation with hydrochloric acid at a concentration of 1~10wt% (e.g., 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, or 10wt%). The precipitate is then dissolved in acetone and precipitated three times with methanol to obtain polymer G2.

[0062] Thirdly, this application provides a photopolymer-type holographic recording medium, which comprises the following components (a) to (h) by weight percentage.

[0063] Component a) 10-30% of the fluorinated resin described in the first aspect

[0064] Component b) Solvent 50-80%

[0065] Component c) Polythiols 5-20%

[0066] Component d) can polymerize 5-20% of monomers.

[0067] Component e) Photosensitive initiation system 0.1~2%

[0068] Component f) Chain transfer agent 0.1~2%

[0069] Component h) optionally contains 0.1-3% additives.

[0070] In the photopolymer holographic recording medium of this application, the content of the fluorinated resin is 10-30%, the content of the solvent is 50-80%, the content of the polythiol is 5-20%, the content of the polymerizable monomer is 5-20%, the content of the photoinitiating system is 0.1-2%, and the content of the additive is 0.1-3%.

[0071] In some embodiments, the solvent includes, but is not limited to, any one or a combination of at least two of the following: dichloromethane, pentane, 2-methylbutane, cyclopentane, acetone, chloroethane, acetonitrile, tetrahydrofuran, methanol, ethanol, isopropanol, n-hexane, ethyl acetate, methyl formate, ethyl formate, or butanone.

[0072] In some embodiments, the polythiols include, but are not limited to, 1,2-ethanedithiol, 1,3-propanedithiol, 1,2-propanedithiol, 1,4-butanedithiol, 1,2-butanedithiol, 2,3-butanedithiol, 1,3-butanedithiol, 1,6-hexanedithiol, 2,3-butanedithiol, dithiodiethylene glycol, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), tris(2-mercaptoethyl)isocyanurate, pentaerythritol tetra(3-mercaptopropionic acid) ester, 1,4-benzenedithiol, 1,3-benzenedithiol, 1,2-benzenedithiol, 2,5-dimercapto-1,3,4-thiadiazole, 2,3-dithio(2 1,4-dithiodimethylthiosulfate, 2,5-dimethylmercapto-1,4-dithiane, 1,4-benzenedimethylthiol, 1,3-benzenedimethylthiol, 1,2-benzenedimethylthiol, 4,4-dimercaptodiphenyl sulfide, rutin dithiol, 2,7-naphthyl dithiol, 1,8-naphthyl dithiol, 2,6-naphthyl dithiol, 2,6-pyridine dithiol, 4,4'-biphenyl dithiol, 2,3-quinoxaloline dithiol, 4-chloro-1,3-benzenediol, 5-bromo-1,3-phenyl dithiol, 3-hydroxypropanedithiol-[1,2] or 3,6-dichloro-1,2-benzenediol, any one or a combination of at least two of these.

[0073] In a further preferred embodiment, the polythiol is a polythiol with a refractive index greater than 1.55.

[0074] In some embodiments, the polymerizable monomer is selected from at least one of allyl ether compounds, propargyl ether compounds, acrylic acid compounds, or methacrylic acid compounds.

[0075] In a further preferred embodiment, the polymerizable monomer is selected from polymerizable monomers with a refractive index greater than 1.55.

[0076] Exemplary examples include, but are not limited to, 1,4-bis(allyloxy)benzene, 1,3-bis(allyloxy)benzene, 1,2-bis(allyloxy)benzene, 4,4'-bis(allyloxy)biphenyl, bis(4-allyloxyphenyl)methane, bis(4-allyloxyphenyl)ether, bis(4-allyloxyphenyl)sulfone, bis(4-allyloxyphenyl)sulfide, 9,10-bis(allyloxy)anthracene, 2,7-bis(allyloxy)naphthalene, 1,5-bis(allyloxy)naphthalene, 4,4'-bis(allyloxy)benzophenone, and bis(4-allyloxyphenyl)diphenylmethane. bis(4-allyloxy-3-methylphenyl) ether, bis(4-allyloxy-2-chlorophenyl) ether, bis(4-allyloxy-3-bromophenyl) ether, bis(4-allyloxy-2-nitrophenyl) ether, bis(4-allyloxy-3-methoxyphenyl) ether, bis(4-allyloxy-2,6-dimethylphenyl) ether, bis(4-allyloxy-3,5-di-tert-butylphenyl) ether, bis(4-allyloxy-2-hydroxyphenyl)methane, bis(4-allyloxyphenyl) disulfide, bis(4-allyloxyphenyl) selenide, bis(4-allyloxyphenyl) telluride, bis(4-allyloxyphenyl) phenyl)siloxane, bis(4-allyloxyphenyl)boronic acid ester, bis(4-allyloxyphenyl)phosphate, bis(4-allyloxyphenyl)carbonate, bis(4-allyloxyphenyl)carbamate, bis(4-allyloxyphenyl)urea, bis(4-allyloxyphenyl)thiourea, bis(4-allyloxyphenyl)sulfonamide, bis(4-allyloxyphenyl)trifluoromethanesulfonamide, bis(4-allyloxyphenyl)maleimide, bis(4-allyloxyphenyl)phthalimide, bis(4-allyloxyphenyl)naphthalenedicarboximide, bis(4-allyloxyphenyl)fluorene, bis(4-allyloxyphenyl) The first one or a combination of at least two of the following: bis(4-allyloxyphenyl)carbazole, bis(4-allyloxyphenyl)dibenzofuran, bis(4-allyloxyphenyl)dibenzothiophene, bis(4-allyloxyphenyl)phenoxazine, bis(4-allyloxyphenyl)phenthiazine, bis(4-allyloxyphenyl)triphenylamine, bis(4-allyloxyphenyl)triphenylmethane, bis(4-allyloxyphenyl)triphenylsilane, bis(4-allyloxyphenyl)triphenylphosphine, bis(4-allyloxyphenyl)triphenylphosphine oxide, bis(4-allyloxyphenyl)triphenylborane, and bis(4-allyloxyphenyl)triphenylgermanane.

[0077] For example, the propargyl ether compounds include, but are not limited to, 1,4-bis(propargyloxy)benzene, 1,3-bis(propargyloxy)benzene, 1,2-bis(propargyloxy)benzene, 4,4'-bis(propargyloxy)biphenyl, bis(4-propargyloxyphenyl)methane, bis(4-propargyloxyphenyl)ether, bis(4-propargyloxyphenyl)sulfone, bis(4-propargyloxyphenyl)sulfide, 9,10-bis(propargyloxy)anthracene, 2,7-bis(propargyloxy)naphthalene, 1,5-bis(propargyloxy)naphthalene, 4,4'-bis(propargyloxy)benzophenone, and bis(4-propargyloxyphenyl)diphenylmethane. bis(4-propynoxy-3-methylphenyl) ether, bis(4-propynoxy-2-chlorophenyl) ether, bis(4-propynoxy-3-bromophenyl) ether, bis(4-propynoxy-2-nitrophenyl) ether, bis(4-propynoxy-3-methoxyphenyl) ether, bis(4-propynoxy-2,6-dimethylphenyl) ether, bis(4-propynoxy-3,5-di-tert-butylphenyl) ether, bis(4-propynoxy-2-hydroxyphenyl)methane, bis(4-propynoxyphenyl) disulfide, bis(4-propynoxyphenyl) selenide, bis(4-propynoxyphenyl) telluride, bis(4-propynoxyphenyl) phenyl)siloxane, bis(4-propoxyphenyl)boronic acid ester, bis(4-propoxyphenyl)phosphate, bis(4-propoxyphenyl)carbonate, bis(4-propoxyphenyl)carbamate, bis(4-propoxyphenyl)urea, bis(4-propoxyphenyl)thiourea, bis(4-propoxyphenyl)sulfonamide, bis(4-propoxyphenyl)trifluoromethanesulfonamide, bis(4-propoxyphenyl)maleimide, bis(4-propoxyphenyl)phthalimide, bis(4-propoxyphenyl)naphthalenedicarboximide, bis(4-propoxyphenyl)fluorene, bis(4-propoxyphenyl) The following are any one or a combination of at least two of the following: bis(4-propoxyphenyl)carbazole, bis(4-propoxyphenyl)dibenzofuran, bis(4-propoxyphenyl)dibenzothiophene, bis(4-propoxyphenyl)phenoxazine, bis(4-propoxyphenyl)phenthiazine, bis(4-propoxyphenyl)triphenylamine, bis(4-propoxyphenyl)triphenylmethane, bis(4-propoxyphenyl)triphenylsilane, bis(4-propoxyphenyl)triphenylphosphine, bis(4-propoxyphenyl)triphenylphosphine oxide, bis(4-propoxyphenyl)triphenylborane, and bis(4-propoxyphenyl)triphenylgermanane.

[0078] Exemplary examples include, but are not limited to, 1,4-phenyl diacrylate, 1,3-phenyl diacrylate, 1,2-phenyl diacrylate, 4,4'-biphenyl diacrylate, bisphenol A diacrylate, bisphenol F diacrylate, bisphenol S diacrylate, bis(4-acrylate phenyl)methane, bis(4-acrylate phenyl) ether, bis(4-acrylate phenyl) sulfone, 2,6-naphthalene diacrylate, 2,7-naphthalene diacrylate, 1,5-naphthalene diacrylate, 1,8-naphthalene diacrylate, 9,10-anthracene diacrylate, bis(4- Fibre phenyl sulfide, bis(4-acrylate phenyl) disulfide, bis(4-acrylate phenyl)amine, bis(4-acrylate phenyl)trifluoromethanesulfonamide, bis(4-acrylate phenyl)sulfonamide, bis(4-acrylate-2-chlorophenyl) ether, bis(4-acrylate-3-bromophenyl) ether, bis(4-acrylate-2-nitrophenyl) ether, bis(4-acrylate-3-methoxyphenyl) ether, bis(4-acrylate-2,6-dimethylphenyl) ether, bis(4-acrylate-3,5-di-tert-butylphenyl) ether, bis(4-acrylate- 2-Hydroxyphenyl)methane, 4,4'-benzophenone diacrylate, bis(4-acrylate phenyl)benzophenone, bis(4-acrylate phenyl)fluorene, bis(4-acrylate phenyl)carbazole, bis(4-acrylate phenyl)dibenzofuran, bis(4-acrylate phenyl)dibenzothiophene, bis(4-acrylate phenyl)phenoxazine, bis(4-acrylate phenyl)phenothiazine, bis(4-acrylate phenyl)triphenylamine, bis(4-acrylate phenyl)siloxane, bis(4-acrylate phenyl)boronic acid ester, bis(4-acrylate phenyl)phosphate ester, bis( The following are any one or a combination of at least two of the following: 4-acrylate phenyl) carbonate, bis(4-acrylate phenyl) carbamate, bis(4-acrylate phenyl) urea, bis(4-acrylate phenyl) thiourea, bis(4-acrylate phenyl) maleimide, bis(4-acrylate phenyl) phthalimide, bis(4-acrylate phenyl) naphthyldicarboximide, bis(4-acrylate phenyl) triphenylmethane, bis(4-acrylate phenyl) triphenylsilane, bis(4-acrylate phenyl) triphenylphosphine, and bis(4-acrylate phenyl) triphenylphosphine oxide.

[0079] Exemplary examples include, but are not limited to, 1,4-phenylenedimethacrylate, 1,3-phenylenedimethacrylate, 1,2-phenylenedimethacrylate, 4,4'-biphenylenedimethacrylate, bisphenol A dimethacrylate, bisphenol F dimethacrylate, bisphenol S dimethacrylate, bis(4-methacrylate phenyl)methane, bis(4-methacrylate phenyl) ether, bis(4-methacrylate phenyl) sulfone, 2,6-naphthalene dimethacrylate, 2,7-naphthalene dimethacrylate, 1,5-naphthalene dimethacrylate, 1,8-naphthalene dimethacrylate, and 9,10-anthracene dimethylpropene. Ester, bis(4-methacrylate phenyl) sulfide, bis(4-methacrylate phenyl) disulfide, bis(4-methacrylate phenyl)amine, bis(4-methacrylate phenyl)trifluoromethanesulfonamide, bis(4-methacrylate phenyl)sulfonamide, bis(4-methacrylate-2-chlorophenyl) ether, bis(4-methacrylate-3-bromophenyl) ether, bis(4-methacrylate-2-nitrophenyl) ether, bis(4-methacrylate-3-methoxyphenyl) ether, bis(4-methacrylate-2,6-dimethylphenyl) ether, bis(4-methacrylate-3,5-di-tert-butylphenyl) ether, bis(4-methyl 2-hydroxyphenyl)methane, 4,4'-benzophenone dimethacrylate, bis(4-methacrylate phenyl)benzophenone, bis(4-methacrylate phenyl)fluorene, bis(4-methacrylate phenyl)carbazole, bis(4-methacrylate phenyl)dibenzofuran, bis(4-methacrylate phenyl)dibenzothiophene, bis(4-methacrylate phenyl)phenoxazine, bis(4-methacrylate phenyl)phenothiazine, bis(4-methacrylate phenyl)triphenylamine, bis(4-methacrylate phenyl)siloxane, bis(4-methacrylate phenyl)boronic acid, bis(4-methacrylate phenyl)phosphate The ester, bis(4-methacrylate phenyl) carbonate, bis(4-methacrylate phenyl) carbamate, bis(4-methacrylate phenyl) urea, bis(4-methacrylate phenyl) thiourea, bis(4-methacrylate phenyl) maleimide, bis(4-methacrylate phenyl) phthalimide, bis(4-methacrylate phenyl) naphthiadicarboximide, bis(4-methacrylate phenyl) triphenylmethane, bis(4-methacrylate phenyl) triphenylsilane, bis(4-methacrylate phenyl) triphenylphosphine, bis(4-methacrylate phenyl) triphenylphosphine oxide, etc., any one or a combination of at least two of the following:

[0080] In some preferred embodiments, component e) of the photosensitive initiation system consists of component i) a photosensitizer and component g) a photoinitiator; preferably, the mass ratio of component i) to component g) is 0.001~0.1:0.1~2. Different broadband responses can be achieved by adjusting the type of photosensitizer. However, when a photoinitiator with an appropriate wavelength is selected in the raw material of the photopolymer holographic recording medium of this application, the photosensitizer may not be added.

[0081] For example, the photosensitizer is a dye with high electron transfer efficiency under light irradiation, including but not limited to any one or a combination of at least two of cyanine dyes, fluorescein dyes, coumarin ketone dyes, nitrogen-containing aromatic heterocyclic compounds, aromatic amine compounds, and benzylidene cycloalkane ketone compounds. Examples include one or a combination of at least two of the following: neomethylene blue, thionine, basic yellow, pinacyanine chloride, rhodamine 6G, gallium cyanide, ethyl violet, Victoria blue R, azurite blue, methylene blue, Astrazon Orange G, Darrow Red, pyrrole red Y, basic red 29, quinaldinium red, crystal violet, ethyl violet, brilliant green, pyrimethium I, azure A, crystal violet cyanonitrile, and malachite green cyanonitrile.

[0082] Furthermore, the photoinitiator is an initiator that can be activated by photochemical radiation and initiate a polymerization reaction of the corresponding polymerizable groups. This includes, but is not limited to, any one or a combination of at least two of aromatic ketone compounds, benzoin and its derivatives, benzoyl ketals, acylphosphine oxides, ammonium arylboronate, chromium salts, aryl diazonium salts, onium salts, and organometallic compounds. Examples include one or a combination of at least two of the following: benzophenone, alkylbenzophenone, 4,4'-bis(dimethylamino)benzophenone, anthrone and halogenated benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, diacylphosphine oxide, phenyl dihydroxyacetate, camphorquinone, α-aminoalkylphenyl ketone, α,α-dialkoxyacetophenone, α-hydroxyalkylphenyl ketone, tetrabutylammonium triphenylhexylborate, tetrabutylammonium tri-(3-fluorophenyl)hexylborate, tetrabutylammonium tri-(3-chloro-4-methylphenyl)hexylborate, ferrocene-based compounds, iodonium salts, thiodonium salts, and hexaaryldiimidazole.

[0083] In some preferred embodiments, the chain transfer agent includes, but is not limited to, one or a combination of at least two of the following: triethylsilane, triphenylmethane, formic acid, isopropanol, benzyl dithiobenzoate, 2-cyano-2-propyl dithiobenzoate, bis(thiobenzoyl) disulfide, 2-cyano-2-propyl dodecyl trithiocarbonate, and O-ethyl-S-(1-methoxycarbonyl)ethyl xanthate.

[0084] In some preferred embodiments, the additive includes one or a combination of at least two of defoamers, leveling agents, and plasticizers.

[0085] Furthermore, when the additive includes an antifoaming agent, the content of the antifoaming agent does not exceed 3% based on the total mass of the photopolymer-type holographic recording medium.

[0086] Furthermore, when the additive includes a leveling agent, the content of the leveling agent does not exceed 3% based on the total mass of the photopolymer-type holographic recording medium.

[0087] Furthermore, when the additive includes a plasticizer, the content of the plasticizer does not exceed 3% based on the total mass of the photopolymer-type holographic recording medium.

[0088] In some preferred embodiments, the defoamer is an organosilicone defoamer, such as one or a combination of at least two of the following: BYK-011, BYK-012, BYK-014, BYK-023, BYK-051N, BYK-085, BYK-1610, BYK-1707, BYK-1740, BYK-1760 manufactured by BYK Corporation, and DC65 and AFE-7820 manufactured by Dow Corning.

[0089] In some preferred embodiments, the leveling agent is a silicone surface additive, such as one or a combination of at least two of BYK-302, BYK-306, BYK-307, BYK-327, BYK-329, BYK-333, BYK-356, BYK-358, BYK-378, BYK-3455, or BYK-3566 manufactured by BYK Corporation.

[0090] In some preferred embodiments, the plasticizer is one or a combination of at least two of toluene, xylene, dimethylformamide, dimethylacetamide, glycerol, or phthalates.

[0091] Fourthly, this application provides a holographic optical element, the raw material of which includes the photopolymer type holographic recording medium as described in the third aspect above.

[0092] Compared with the prior art, this application has the following advantages:

[0093] The fluorinated resin of this application has a low refractive index (refractive index <1.35), which effectively improves the compatibility between the film-forming resin and the recording monomer, and significantly reduces the production cost of the material. When used in conjunction with a high refractive index monomer (refractive index greater than 1.55), it increases the refractive index difference between the recording monomer and the film-forming resin to more than 0.25. This holographic recording medium has a sensitivity greater than 100 cm / mJ, a recording grating diffraction efficiency greater than 95%, a refractive index modulation degree greater than 0.1, and a haze less than 1%. Attached Figure Description

[0094] Figure 1 The infrared spectra of polymers P3-2 and G1-2 prepared in Example 2 are shown.

[0095] Figure 2 An optical photograph of the grating was prepared for application example 1.

[0096] Figure 3 An optical photograph of the grating was prepared for Comparative Example 1. Detailed Implementation

[0097] The technical solution of this application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely to help understand this application and should not be regarded as specific limitations on this application.

[0098] Example 1

[0099] In this embodiment, the synthesis of polymer G1-1 is provided, and the synthesis method is as follows:

[0100] Under an inert gas atmosphere and at -40°C, the thermal initiator azobisisobutyronitrile (1 equivalent), compound P1-1 (300 equivalents), compound P2-1 (300 equivalents), and trichlorofluoroethylene (50 equivalents) were dissolved in the organic solvent dichloromethane. The mixture was then slowly heated and stirred at 30°C for 12 h. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P3-1.

[0101] .

[0102] Under S2 and inert gas protection, polymer P3-1 and triethylamine (mass ratio of polymer P3-1 to triethylamine 1:0.5) were dissolved in the organic solvent acetonitrile and stirred until the polymer dissolved. The mixture was then heated to 60°C and stirred for 10 h. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G1-1.

[0103] .

[0104] Example 2

[0105] In this embodiment, the synthesis of polymer G1-2 is provided, and the synthesis method is as follows:

[0106] Under an inert gas atmosphere and at -50°C, thermal initiator benzoyl peroxide (1 equivalent), compound P1-2 (100 equivalent), compound P2-2 (100 equivalent), and trichlorofluoroethylene (50 equivalent) were dissolved in the organic solvent chloroform. The mixture was then slowly heated and stirred at 50°C for 10 h. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P3-2.

[0107]

[0108] Under S2 and inert gas protection, polymer P3-2 and pyridine (mass ratio of polymer P3-2 to pyridine 1:1) were dissolved in the organic solvent chloroform and stirred until the polymer dissolved. Then, the mixture was heated to 50°C and stirred for 5 h. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G1-2.

[0109] .

[0110] Example 3

[0111] In this embodiment, the synthesis of polymer G1-3 is provided, and the synthesis method is as follows:

[0112] Under an inert gas atmosphere and at -20°C, the thermal initiator azobisisobutyronitrile (1 equivalent), compound P1-3 (500 equivalents), compound P2-3 (800 equivalents), and trichlorotrifluoroethylene (100 equivalents) were dissolved in the organic solvent toluene. The mixture was then slowly heated and stirred at 100°C for 3 hours. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P3-3.

[0113]

[0114] Under S2 and inert gas protection, polymer P3-3 and sodium methoxide (mass ratio of polymer P3-3 to sodium methoxide 1:0.3) were dissolved in the organic solvent toluene and stirred until the polymer dissolved. Then, the mixture was heated to 100°C and stirred for 48 h. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G1-3.

[0115] .

[0116] Example 4

[0117] In this embodiment, the synthesis of polymer G2-1 is provided, and the synthesis method is as follows:

[0118] Under an inert gas atmosphere and at -30°C, thermal initiator azobisisobutyronitrile (1 equivalent), compound P4-1 (100 equivalent), compound P2-4 (100 equivalent), and trichlorotrifluoroethylene (10 equivalent) were dissolved in the organic solvent dichloromethane. The mixture was then slowly heated and stirred at 30°C for 36 h. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P5-1.

[0119]

[0120] Under an inert gas atmosphere, polymer P4-1 and triethylamine (mass ratio of polymer P4-1 to triethylamine 1:0.5) were dissolved in the organic solvent N,N-dimethylformamide and stirred until the polymer dissolved. The mixture was then heated to 140°C and stirred for 3 hours. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G2-1.

[0121] .

[0122] Example 5

[0123] In this embodiment, the synthesis of polymer G2-2 is provided, and the synthesis method is as follows:

[0124] Under an inert gas atmosphere and at -5°C, the thermal initiator azobisisobutyronitrile (1 equivalent), compound P4-2 (1000 equivalent), compound P2-5 (1000 equivalent), and trichlorotrifluoroethylene (50 equivalent) were dissolved in the organic solvent acetonitrile. The mixture was then slowly heated and stirred at 60°C for 20 h. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P5-2.

[0125]

[0126] Under S2 and inert gas protection, polymer P4-2 and triethylamine (mass ratio of polymer P4-2 to triethylamine 1:0.3) were dissolved in the organic solvent acetonitrile and stirred until the polymer dissolved. The mixture was then heated to 50°C and stirred for 48 h. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G2-2.

[0127] .

[0128] Example 6

[0129] In this embodiment, the synthesis of polymer G2-3 is provided, and the synthesis method is as follows:

[0130] Under an inert gas atmosphere and at -20°C, the thermal initiator azobisisobutyronitrile (1 equivalent), compound P4-3 (500 equivalents), compound P2-6 (1000 equivalents), and trichlorotrifluoroethylene (100 equivalents) were dissolved in the organic solvent toluene. The mixture was then slowly heated and stirred at 100°C for 5 h. After the reaction was complete, the resulting polymer was recovered, washed with methanol, and vacuum dried to obtain copolymer P5-3.

[0131]

[0132] Under an inert gas atmosphere (S2), polymer P4-3 and triethylamine (mass ratio of polymer P4-3 to triethylamine 1:0.3) were dissolved in the organic solvent dimethyl sulfoxide and stirred until the polymer dissolved. The mixture was then heated to 170°C and stirred for 3 hours. The resulting mixture was precipitated with 5 wt% hydrochloric acid to remove excess alkali. The precipitate was then dissolved in acetone and precipitated three times with methanol to obtain polymer G2-3.

[0133] .

[0134] The polymers prepared in the above examples were subjected to the following tests:

[0135] Weight-average molecular weight test method: The polymer is dissolved in acetone (concentration ~1 mg / mL), filtered, and the molecular weight of the polymer is determined by gel permeation chromatography (GPC).

[0136] Method for measuring refractive index: The polymer is dissolved in acetone and injected into a mold. After the solvent evaporates, a polymer block is obtained. The block is polished to obtain a smooth surface. The surface is placed on an Abbe refractometer (with bromine naphthalene added in the middle) and the refractive index of the polymer is measured.

[0137] The polymers P3-2 and G1-2 prepared in Example 1 were characterized by infrared spectroscopy (Thermo Scientific, Nicolet iS50), as follows: Figure 1 As shown in the infrared spectrum, compared with P3-2, G1-2 has a lower concentration in the 1600-1750 cm⁻¹ range. -1 A stretching vibration peak of C=C in non-conjugated alkenes appeared at 3000-3020 cm⁻¹. -1 The presence of a weak =CH stretching vibration peak nearby confirms the formation of double bonds in the polymer.

[0138] The weight-average molecular weight and refractive index results of the polymers obtained from the above tests are shown in Table 1.

[0139] Table 1

[0140]

[0141] Application Example 1

[0142] Photopolymer-based holographic recording media were prepared using the polymer G1-1 described above. The specific components and amounts are shown in Table 2.

[0143] Table 2

[0144]

[0145] Application Example 2

[0146] Photopolymer-based holographic recording media were prepared using the polymer G1-2 described above. The specific components and amounts are shown in Table 3.

[0147] Table 3

[0148]

[0149] Application Example 3

[0150] Photopolymer-based holographic recording media were prepared using the polymer G1-3 as described above. The specific components and amounts are shown in Table 4.

[0151] Table 4

[0152]

[0153] Application Example 4

[0154] Photopolymer-based holographic recording media were prepared using the polymer G2-1 described above. The specific components and amounts are shown in Table 5.

[0155] Table 5

[0156]

[0157] Application Example 5

[0158] Photopolymer-based holographic recording media were prepared using the polymer G2-2 described above. The specific components and amounts are shown in Table 6.

[0159] Table 6

[0160]

[0161] Application Example 6

[0162] Photopolymer-based holographic recording media were prepared using the polymer G2-3 described above. The specific components and amounts are shown in Table 7.

[0163] Table 7

[0164]

[0165] Comparative Example 1

[0166] The only difference from Application Example 2 is that G1-2 is replaced with copolymer P3-2 prepared in Example 2.

[0167] Photopolymer sample preparation: Stir and dissolve each component evenly, then use a scraper to coat it onto the substrate surface, bake at 80°C, and after the solvent evaporates, cover with a protective film.

[0168] The testing method for the performance of holographic recording media includes the following steps:

[0169] For the holographic recording medium, solid-state lasers with wavelengths of 633nm, 457nm, 532nm, and 633nm were used as light sources according to their photosensitive wavelengths. After passing through a beam expander, beam splitter, and half-wave plate, two beams with the same intensity and a diameter of 8 mm were obtained. The two beams were intersected and exposed within the prepared holographic recording medium at an intensity of 3mW / cm². 2 The detection light source uses a 785 nm wavelength solid-state laser that does not react with the recording medium. The detection light is incident on the exposure area from the Bragg angle. The transmitted light and diffracted light are monitored in real time by a photodetector. The single grating diffraction efficiency (η) and the photosensitivity (S) of the photopolymer holographic recording medium are calculated by formulas (1) to (3).

[0170]

[0171] In the formula, η is the diffraction efficiency, η max For the highest diffraction efficiency, I d For diffracted light, I t S represents transmitted light, S represents photosensitivity, E represents exposure energy, and ΔE represents the exposure energy required to achieve the highest diffraction efficiency.

[0172] After the grating recording is completed, its diffraction efficiency at different angles is tested and obtained by fitting based on Kogelnik's coupled-wave theory.

[0173] The haze of the sample was obtained by measuring with a haze meter.

[0174] Table 8

[0175]

[0176] The applicant declares that this application illustrates the fluorinated resin, photopolymer-type holographic recording medium, its preparation method, and its application through the above embodiments. However, this application is not limited to the above embodiments, meaning that this application does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this application, equivalent substitutions of the raw materials used, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this application.

Claims

1. A fluorinated resin, characterized in that, The fluorinated resin has the structure shown in G1 or G2 as follows: ； Where x is an integer from 100 to 200, y is an integer from 20 to 400, z is an integer from 100 to 2000, a is an integer from 10 to 150, b is an integer from 10 to 150, n is an integer from 1 to 9, R1 represents hydrogen or methyl, and R2 represents a straight-chain alkyl or branched-chain alkyl from C1 to C12, or a cycloalkyl from C3 to C12.

2. The fluorinated resin according to claim 1, characterized in that, R2 is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl, etc. dodecyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl.

3. The fluorinated resin according to claim 1, characterized in that, The fluorinated resin is any one of the following resins: 。 4. The method for preparing the fluorinated resin according to any one of claims 1-3, characterized in that, The preparation method includes the following steps: (1) Synthesis of fluorinated resin G1: S1-1, compound P1, compound P2, and trichlorofluoroethylene undergo a polymerization reaction to obtain polymer P3, as shown in the following reaction formula: ； S1-2 and polymer P3 undergo an elimination reaction in the presence of an alkaline substance to yield fluorinated resin G1, as shown in the following reaction formula: ； (2) Synthesis of fluorinated resin G1: S2-1, compound P4, compound P2, and monochlorotrifluoroethylene undergo a polymerization reaction to obtain polymer P5, as shown in the following reaction formula: ； S2-2 and polymer P5 undergo an elimination reaction in the presence of an alkaline substance to yield fluorinated resin G2, as shown in the following reaction formula: 。 5. The preparation method according to claim 4, characterized in that, The molar ratio of compound P1 to compound P2 in step S1-1 is (0.1-10):1; The molar ratio of compound P1 to trichlorotrifluoroethylene in step S1-1 is 1-100:

1.

6. The preparation method according to claim 4, characterized in that, The polymerization reaction described in step S1-1 is carried out under the initiation of a thermal initiator; The thermal initiator includes any one or a combination of at least two of the following: azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, dicumyl peroxide, potassium persulfate, ammonium persulfate, diisopropyl peroxide, dicyclohexyl peroxide, lauroyl peroxide, tert-butyl hydroperoxide, acetylacetone peroxide, di-tert-butyl peroxide, or di(4-tert-butylcyclohexyl) peroxide. The molar ratio of the thermal initiator to compound P1 is 1:100-1000.

7. The preparation method according to claim 4, characterized in that, The polymerization reaction described in step S1-1 is carried out in an organic solvent, which includes one or a combination of at least two of petroleum ether, dichloromethane, trichloromethane, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide. In step S1-1, the thermal initiator, compound P1, compound P2 and trichlorotrifluoroethylene are dissolved in an organic solvent at an environment of -70~-5℃. The polymerization reaction in step S1-1 is carried out at a temperature of 20~100℃ and for a reaction time of 1~36 h. The polymerization reaction described in step S1-1 is carried out under the protection of an inert gas, namely nitrogen.

8. The preparation method according to claim 4, characterized in that, The base mentioned in steps S1-2 includes any one or a combination of at least two of the following: triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, sodium methoxide, sodium ethoxide, or potassium tert-butoxide. The mass ratio of polymer P3 to alkaline substance in steps S1-2 is 1:0.3~1; The elimination reaction described in steps S1-2 is carried out in a solvent, which includes one or a combination of at least two of petroleum ether, dichloromethane, trichloromethane, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide. The elimination reaction in steps S1-2 is carried out at a temperature of 50~200℃ for 3~48 h. The elimination reaction described in steps S1-2 is carried out under the protection of an inert gas, namely nitrogen.

9. The preparation method according to claim 4, characterized in that, The molar ratio of compound P4 to compound P2 in step S2-1 is (0.1-10):1; The molar ratio of compound P4 to trichlorotrifluoroethylene in step S2-1 is 1-100:

1.

10. The preparation method according to claim 4, characterized in that, The polymerization reaction described in step S2-1 is carried out under the initiation of a thermal initiator; The thermal initiator includes any one or a combination of at least two of the following: azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, dicumyl peroxide, potassium persulfate, ammonium persulfate, diisopropyl peroxide, dicyclohexyl peroxide, lauroyl peroxide, tert-butyl hydroperoxide, acetylacetone peroxide, di-tert-butyl peroxide, or di(4-tert-butylcyclohexyl) peroxide. The molar ratio of the thermal initiator to compound P4 is 1:100-1000.

11. The preparation method according to claim 4, characterized in that, The polymerization reaction described in step S2-1 is carried out in an organic solvent, which includes one or a combination of at least two of petroleum ether, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide. In step S2-1, the thermal initiator, compound P1, compound P2 and trichlorotrifluoroethylene are dissolved in an organic solvent at an environment of -70~-5℃. The polymerization reaction in step S2-1 is carried out at a temperature of 20~100℃ for 1~36 h. The polymerization reaction described in step S2-1 is carried out under the protection of an inert gas, namely nitrogen.

12. The preparation method according to claim 4, characterized in that, The base mentioned in step S2-2 includes any one or a combination of at least two of the following: triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, sodium methoxide, sodium ethoxide, or potassium tert-butoxide; The mass ratio of polymer P4 to alkaline substance in step S2-2 is 1:0.3~1; The elimination reaction described in step S2-2 is carried out in a solvent, which includes one or a combination of at least two of petroleum ether, dichloromethane, trichloromethane, ethyl acetate, tetrahydrofuran, toluene, acetonitrile, N,N-dimethylformamide, or dimethyl sulfoxide. The elimination reaction in step S2-2 is carried out at a temperature of 50~200℃ for 3~48 h. The elimination reaction described in step S2-2 is carried out under the protection of an inert gas, namely nitrogen.

13. A photopolymer-based holographic recording medium, characterized in that, The photopolymer holographic recording medium comprises the following components (a) to (h) by weight percentage. Component a) 10-30% of the fluorinated resin according to any one of claims 1-3 Component b) Solvent 50-80% Component c) Polythiols 5-20% Component d) can polymerize 5-20% of monomers. Component e) Photosensitive initiation system 0.1~2% Component f) Chain transfer agent 0.1~2% Component h) optionally contains 0.1-3% additives.

14. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The solvent includes any one or a combination of at least two of the following: dichloromethane, pentane, 2-methylbutane, cyclopentane, acetone, chloroethane, acetonitrile, tetrahydrofuran, methanol, ethanol, isopropanol, n-hexane, ethyl acetate, methyl formate, ethyl formate, or butanone.

15. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The polythiols include 1,2-ethanedithiol, 1,3-propanedithiol, 1,2-propanedithiol, 1,4-butanedithiol, 1,2-butanedithiol, 2,3-butanedithiol, 1,3-butanedithiol, 1,6-hexanedithiol, 2,3-butanedithiol, dithiodiglycol, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), tris(2-mercaptoethyl)isocyanurate, pentaerythritol tetra(3-mercaptopropionic acid) ester, 1,4-benzenedithiol, 1,3-benzenedithiol, 1,2-benzenedithiol, 2,5-dimercapto-1,3,4-thiadiazole, and 2,3-dithio(2 1,4-dithiodimethylthiosulfate, 2,5-dimethylmercapto-1,4-dithiane, 1,4-benzenedimethylthiol, 1,3-benzenedimethylthiol, 1,2-benzenedimethylthiol, 4,4-dimercaptodiphenyl sulfide, rutin dithiol, 2,7-naphthyl dithiol, 1,8-naphthyl dithiol, 2,6-naphthyl dithiol, 2,6-pyridine dithiol, 4,4'-biphenyl dithiol, 2,3-quinoxaloline dithiol, 4-chloro-1,3-benzenediol, 5-bromo-1,3-phenyl dithiol, 3-hydroxypropanedithiol-[1,2] or 3,6-dichloro-1,2-benzenediol, any one or a combination of at least two of these.

16. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The polythiol is a polythiol with a refractive index greater than 1.

55.

17. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The polymerizable monomer is selected from at least one of allyl ether compounds, propargyl ether compounds, acrylic acid compounds, or methacrylic acid compounds.

18. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The polymerizable monomer is selected from polymerizable monomers with a refractive index greater than 1.

55.

19. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The photoinitiating system of component e) is composed of component i) photosensitizer and component g) photoinitiator; the mass ratio of component i) to component g) is 0.001~0.1:0.1~2.

20. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The chain transfer agent includes one or a combination of at least two of the following: triethylsilane, triphenylmethane, formic acid, isopropanol, benzyl dithiobenzoate, 2-cyano-2-propyl dithiobenzoate, bis(thiobenzoyl) disulfide, 2-cyano-2-propyl dodecyl trithiocarbonate, and O-ethyl-S-(1-methoxycarbonyl)ethyl xanthate.

21. The photopolymer-type holographic recording medium according to claim 13, characterized in that, The additives include one or a combination of at least two of the following: defoamers, leveling agents, and plasticizers.

22. A holographic optical element, characterized in that, The raw material of the holographic optical element includes any one of the photopolymer holographic recording media according to claims 13-21.

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