Technical Field The present invention relates to monomers to develop new, UV-curable, fluorinated polyacrylate compounds for information and electronic devices, and more particularly to, new acrylate monomers and polymers which are fluorinated at the polymeric main chain and thus show low optical transmission loss at optical communication wavelength regions of 1. 3 J, m and 1.5 um and which have'low birefringence and high thermal stability as a result of the fine control of refractive index, as well as a method fcr preparing them.

Background Art In order to realize the huge capacity of optical communication and the ultra-high speed of information recording and processing in cope with the high-degree information and communication society in the coming 21-century, the application of photonic technology is inevitable since only the use of electronic technology encounters limitations. As the speed of an optical transmitter (~1015 Hz) is far faster than that of an

electronic transmitter (~109 Hz), it was expected that the application of this ultra-high speed characteristic of light to telecommunication systems would overcome limitations in current information process capability. By this expectation, researches on optical communication were started. As an optical waveguide device, which had been developed using a polymer by Akzo Novel (the Netherlands), was recently sold under the trademark BeamBOX a competition to develop polymeric materials for passive optical devices is being promoted between Japan and USA enterprises. The initial research team manufactured a linear optical waveguide device using mainly PMMA. However, PMMA shows high optical loss in the near-infrared region, and in an attempt to solve this problem, Japan's NTT prepared a copolymer substituted with deuterium and embodied optical devices having a very low optical loss of about 0.08 dB/cm at 1.3 pm using a material of well- controlled refractive index as a cladding and core. However, the PMMA system has a Tg of about 100 °C, which indicates low thermal stability. To improve the problem of low thermal stability, Japan's NTT developed and presented a deuterated polysiloxane (Electron. Lett., 30,958 (1994) ), and a fluorinated polyimide.

Fluorinated polyimide, which was developed and commercialized for use in optical devices by Amoco Chemical Co. (USA) and sold under the trademark Ultradel 9000D, has problems of relatively high optical loss and high birefringence, but is designed to be photo-crosslinked such that it can be easily fabricated into

optical devices by photolithography. Recently, Allied Signal Co.

(USA) reported the development of UV-curable fluorinated polyacrylate (USP No. 6, 306, 563). As described above, many polymeric materials for optical waveguide devices have been studied, but their practical use is still in an insufficient condition.

Considering that an optical source for optical communication currently utilizes a 1. 3 tm laser but will use a 1.55 pm laser in the near future, new polymers having little or no optical absorption at a wavelength range of 1.1-1. 6 jjm need to be developed. Since general polymers are composed of hydrocarbon < (CH), a primary or secondary absorption band by C-H bond stretching needs to be considered. In other words, new polymers, which don't have such an absorption region while showing a high dn/dT value should be developed. In fact, in the optical waveguide material research field, polymers where a C-H bond was substituted with a C-D or C-F bond are used in order to reduce the optical loss in optical waveguides (Makromol. Chem. , 189, 2861 (1988) ). For example, the results of studies on polymers, such as deuterated or fluorinated PMMA or polyimide, are being reported (Macromolecules, 27,6665 (1994) ). To fabricate thermo- optical devices having reliability in addition to this optical absorption characteristic, a multi-layer thin film must be able to be formed. Thus, amorphous polymers need to be developed, which have excellent chemical resistance and thermal resistance,

and low mechanical strength and dielectric properties and do not show optical absorption or scattering caused by the chemical structure itself.

The use of photocuring technology was rapidly increased for the past ten years. The photocuring includes polymerization by the crosslinking of monomers or polymerization by radiation. The polymerization mechanism can be described by radical or cationic polymerization, and radical initiation polymerization is most generally used. Most of commercial photocuring systems consist of multifunctional acrylate monomers and a free radical photoinitiator. The photocuring, which utilizes ultraviolet rays, has many advantages, such as the simplification of a manufacturing process, and the reduction of costs. With a dramatic growth in electric and communication industries, the development of photocurable materials for optical waveguide and interconnect applications is urgently required. Of well-known polymeric compounds having optical properties, polyacrylate- based compounds have been recently studied as optical waveguide materials due to the low birefringence and optical loss of a wide range of monomers. Particularly, halofluorinated acrylate, which is a transparent monomer useful as a waveguide material having optical characteristics, can be photocrosslinked by a photoinitiator. However, the simplification of a process by direct irradiation and the improvement of thermal stability of a material still remain as problems to be solved.

Brief Description of Drawings FIG. 1 shows the IR spectrum of a (T4F8A/B4F8FA 70: 30) copolymer, measured on a K13r pellet ; and FIG. 2 shows the absorption spectrum of photocrosslinked perfluorinated copolyacrylate in the near-infrared region.

Disclosure of Invention An object of the present invention is to provide new fluorinated acrylate : monomers and polymers for optical waveguide materials, which have low birefringence, excellent thermal properties and very low optical transmission loss and used to develop UV-curable fluorinated polyacrylates, as well as methods for preparing them.

To achieve the above object, the present invention provides new fluorinated acrylate monomers and polymers for optical waveguide materials, as well as their preparation methods, which are described by chemical mechanisms in the following reaction schemes 1-13. The concrete structure and preparing method of the monomers and polymers will be described in detail with reference to examples.

[Reaction Scheme 1]

1 1 HO--'Rf Methyleneehloride/RT HO'Rf'0-THH 0wherein Rf is one selected from and k is an integer selected from 2-10.

[Reaction Scheme 2] wherein R1, R2, R3 and R4 which may be the same or different are each independently selected from the following group; a, b, c and d which may be the same or different are each independently an integer selected from 0-4; a+b+c+d=4; and k is an integer selected from 2-10.

[Reaction Scheme 3]

R1, R2, R3, R4, a, b, c and d are the same as defined above; R1l, R22, R33 and R44 which may be the same or different are each independently selected from the following group ;

and k is an integer selected from 2-10.

[Reaction Scheme 4]

wherein the substituent groups and repeating units are the same as defined as above.

[Reaction Scheme 5]

(HO4C>oR11tO a \ A/a 'c b o 0-R22a b 0 O. b (+/tF2t /c 0 Y

O4RnO4C SoH)wherein Y is one selected from H, F, CF3, and Cl ; and the remaining substituent groups and repeating units are the same as defined above.

[Reaction Scheme 6] <BR> <BR> HOCH 2 (CF2)kCH2OH<BR> F-R-F # HO (C) O-R-O (C) OH<BR> CsCO3/DMF/RT/20h F2k F2k wherein R is one selected from the following group; and k is an integer selected from 2-10.

[Reaction Scheme 7]

wherein R, k and Y are the same as defined above.

[Reaction Scheme 8]

wherein Rf is one selected from where k is, an integer selected from 2-10.

[Reacion Scheme 9]

wherein Rf is the same as defined above.

[Reaction Scheme 10] F F F F yloyl layi xride ,"r - 0*'Fo-"'DPI t wherein Rf is the same as defined above.

[Reaction Scheme 11] Cl Hf H t n"m Xo<<ORh l o 0 rIo ORh ' Iianene170'C :/Oh Ff H O ORh wherein Rf is the same as defined above, and Rh is one selected from

[Reaction Scheme 12] H 7 .. - O loride Rf Rf zu C ORh ORh wherein Rf and Rh are the same as defined above.

[Reaction Scheme 13] tCtCt cit-C Rf'ORh /n Bmune/o'C 0 Rf ORh

wherein Rf and Rh are the same as defined above.

Best Mode for Carrying Out the Invention The following substances were used in the present invention, but they were used for convenience and other substances may also be used if they are selected by a person skilled in the art to facilitate the practice of the present invention.

In the following example, pentaerythritol, hexafluorobenzene, decafluorobiphenyl, decafluorobenzophenon, sulfonylchloride, pentafluorophenyl sulfide, 2-chloro-acryloyl chloride, 2-trifluoromethylacryloyl chloride, 2-fluoroacryloyl chloride, 3, 4-dihydro-2H-pyran,. 2,2, 3,3, 4,4, 5, 5-octafluoro-1, 6- hexanediol, NaH (60% dispersion in mineral oil), acryloly chloride, 2,3, 5, 6-tetrafluo]-obenzene-1, 4-diol, 2,2-bis (4- hydroxyphenyl) hexafluoropropane, 2-hydroxy-3-phenoxypropyl acetate, azobisisobutyronitrile,, aceton-d6, chroloform-d6, which are commercially available from Aldrich Co. , were used, and 1- methoxy-2-propanol acetate which is commercially available from Dow Chemical Co. was used. Potassium carbonate was used after drying. N, N-dimethyl formamide, tetrahydrofuran, methylene chloride and benzene, which are commercially available from Sam Jun Chemical Co. , was used after purification, and substances, such as chlorobenzene, p-toluenesulfonic acid, n-hexane, and ethyl acetate, were used without separate purification. The structure of prepared intermediates or monomers was examined by _NMRt 13 C-NMR and FT-IR. The H-NMR results were recorded using

a Varian 300 spectrometer, and all chemical shifts were recorded in ppm units per tetramethyl silane as the internal standard. IR spectra were measured on KBr pellets and silicon wafers using a Perkin-Elmer spectrometer. To evaluate thermal stability, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed in a 951 TGA and a Dupont 951 Thermal Analyzer equipped with a 910S DSC module, respectively, under a nitrogen atmosphere at a heating rate of 10 °C/min. The refractive index and birefringence of a polymer thin film were measured with a PCA-2000 prism coupler (Sharon Inc. , Korea).

Example 1: Synthesis of 2,2, 3,3, 4,4, 5, 5-octafluoro- (6- tetrahydro-pyran-2-yloxy)-hexan-'l-ol To a solution of 15 g (57.2 mmol) of 2, 2, 3, 3,4, 4,5, 5- octafluoro-1, 6-hexanediol and 150 mg of p-toluenesulfonic acid in 300 ml of dichloromethane, 2. 6 ml (28.5 mmol) of 3,4-dihydro- 2H-pyrane was slowly added dropwise and stirred for 3 hours at room temperature. After completion of the reaction as monitored by TLC, the reaction solution was washed once with 100 ml of a saturated aqueous solution of sodium bicarbonate, and the organic layer was washed with distilled water (50 ml x 2), dried with anhydrous MgSO4 and filtered. The filtrate was distilled under reduced pressure, and the product was purified by column chromatography (hexane : ethyl acetate = 3 : 1) to give 8.9 g (90% yield) of the title compound as a colorless solid.

1H-NMR (300MHz, CDC13) : 1. 59~1. 85 (m, 6H), 3.12 (s, OH), 3. 8-4. 1 (m, 6H), 4.75 (s, 1H) ; 19F-NMR : -120. 5 (d, 2F),-123. 07 (t, 2F),-124. 44 (m, 4F).

Example 2: Synthesis of tetrakis- (2, 3,5, 6-pentafluoro- phenoxy) methylmethane 'Under a nitrogen stream, 2 g (14.7 mmol) of pentaerythritol was dissolved in 50 ml of anhydrous dimethylformamide in a round-bottom flask and added with 2.64 g (66.1 mmol) of NaH (60% dispersion in mineral oil). The solution was stirred for 2 hours at room temperature. In another flask, 7.6 ml (66.1 mmol) of hexafluorobenzene was dissolved in 100 ml of anhydrous dimethylformamide, to which the reaction solution prepared previously was then slowly added dropwise at-10 °C. After completion of the addition, the mixture was stirred for 20 hours at room temperature. After completion of the reaction as monitored by TLC, the reaction solution was distilled under reduced pressure to remove the solvent, and the product was purified by column chromatography (hexane) to give 9.4 g (80% yield) of the title compound as a white solid.

1H-NMR (300MHz, CDCl3) : 4.56 (s, 2H, CH2) ; 19F-NMR :-157. 15 (d, 2F), -162. 26 (t, 1F),-162. 86 (t, 2F) Example 3: Synthesis of tetrakis- {4'- [6- (2-tetrahydro-pyranyloxy)-

2, 2, 3, 3, 4, 4, 5, 5, 6, 6-octafluorohexyloxy] -2, 3, 5, 6- tetrafluorophenoxymethyllmethane Under a nitrogen stream in a round-bottom flask, 1 g (1.25 mmol) of tetrakis- (2, 3, 5, 6-pentafluorophenoxy) methylmethane was dissolved in 30 ml of anhydrous tetrahydrofuran, to which 0.21 g (5.37 mmol) of NaH (60% dispersion in mineral oil) was added.

The solution was stirred for 30 minutes at room temperature. In another flask, 1. 86 g (5.37 mmol) of 2,2, 3, 3, 4, 4, 5, 5-octafluoro- (6-tetrahydropyran-2-yloxy)-hexan-l-ol was dissolved in 10 ml of tetrahydrofuran, to which the reaction solution prepared previously was then slowly added dropwise. After completion of the addition, the mixture was stirred for 20 hours at room temperature. After completion of the reaction as indicated by TLC, the reaction mixture was distilled under reduced pressure to remove the solvent, and the product was purified by column chromatography (hexane : ethyl acetate = 3: 1) to give 2.5 g (95% yield) of the title compound as a colorless solid.

1H-NMR (300MHz, CDC13) : 1. 53-1. 84 (m, 6H), 3.57 (t, 1H), 3.79 (m, 1H), 3.96 (t, 1H), 4.75 (m, 4H), 4.76 (s, 1H) ;. 19F-NMR : - 120.36 (s, 2F), -121. 58 (t, 2F),-123. 96 (m, 4F), -155. 87 (d, 2F), -157. 07 (d, 2F) Synthesis of tetrakis- {4'- [8- (2-tetrahydropyranyloxy)- 2,2, 3, 3,4, 4,5, 5,6, 6,7, 7,8, 8-dodecafluorooctyloxy]-2, 3, 5,6- tetrafluorophenoxymethyl} methane

Under a nitrogen stream in a round-bottom flask, 1 g (1. 25 mmol) of tetrakis- (2, 3,5, 6-pentafluorophenoxy) methylmethane was dissolved in 30 ml of anhydrous tetrahydrofuran, to which 0. 21 g (5.37 mmol) of NaH (60% dispersion in mineral oil) was added.

The solution was stirred for 30 minutes at room temperature. In another flask, 3.90 g (8.75 mmol) of 2,2, 3, 3, 4,4, 5,5, 6,6, 7,7- dodecafluoro-8- (tetrahydro-pyran-2-yloxy)-octan-1-ol was dissolved in 10 ml of tetrahydrofuran, to which the reaction solution prepared previously was then slowly added dropwise.

After completion of the addition, the mixture was stirred for 20 hours at room temperature. After completion of the, reaction as monitored by TLC, the reaction mixture was distilled under reduced pressure to remove the solvent, and the product was purified by column chromatography (hexane: ethyl acetate = 3 : 1) to give 2.0 g (70% yield) of the title compound as a colorless solid.

1H-NMR (300MHz, CDC13) : 1. 53-1. 84 (m, 6H), 3.58 (t, 1H), 3.80 (m, 1H), 4.02 (t, 1H), 4.72 (m, 4H), 4.96 (s, 1H) ; 19F-NMR : - 121. 26 (s, 2F), -121. 78 (t, 2F),-124. 02 (m, 8F), -155. 87 (d, 2F), -157. 07 (d, 2F) Example 4 : Synthesis of tetrakis- [4'- (6-hydroxy- 2,2, 3,3, 4,4, 5,5, 6, 6-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- phenoxymethyl] methane 1.54 g (0.73 mmol) of tetrakis- {4'- [6- (2-tetrahydro-

pyranyloxy)-2, 2,3, 3,4, 4,5, 5,6, 6-octafluorohexyloxy]-2, 3,5, 6- tetrafluoro-phenoxymethyl} methane was dissolved in 20 ml of methanol, to which 150 mg of p-toluenesulfonic acid was then added. The solution was stirred for 6 hours at room temperature.

After completion of the reaction as indicated by TLC, the reaction was terminated by the addition of triethylamine. The reaction solution was distilled under reduced pressure to remove the methanol, and the product was dissolved in 20 ml of chloroform, washed with distilled water (50 ml x 2), dried with anhydrous MgSO4 and filtered. The filtrate was distilled under reduced pressure and the product was purified by column chromatography (hexane : ethyl acetate = 3: 1) to give 1.2 g (86% yield) of the title compound as a colorless solid.

1H-NMR (300MHz, Acetone-d6) : 3.62 (s, OH), 4.12 (t, 2H), 4.70 (s, 2H), 4. 8 : (m, 2H) ; 19F-NMR :-121. 2 (t, 2F), -121. 9 (t, 2F), - 122.1 (m, 4F), -157. 88 (d, 2F),-158. 87 (d, 2F) Example 5: Synthesis of tetrakis [4'-(6-acryloxy-2,2,3,3,4,4,5,5-octa- fluorohexyloxy)-2, 3, 5, 6-tetrafluorophenoxymethyl] methane (T4F8A) Under a nitrogen stream, 1. 24 g (0.70 mmol) of tetrakis- [4'-(6-hydroxy-2, 2,3, 3,4, 4,5, 5,6, 6-octafluorohexyloxy)-2, 3,5, 6- tetrafluoro-biphenoxymethyljmethane was dissolved in 20 ml of dichloromethane, to which 0.5 g (4.3 mmol) of triethylamine was then added. The solution was stirred for 30 minutes at room

temperature, to which 0.27 g (4.3 mmol) of acryloyl chloride was then added dropwise in an ice bath. After completion of the reaction as monitored by TLC, the reaction solution was distilled under vacuum to remove the dichloromethane, and the product was dissolved in 20 ml of chloroform, washed with distilled water (50 ml x 2), dried with anhydrous MgS04 and filtered. The filtrate was distilled under reduced pressure and purified by column chromatography (hexane : ethyl acetate = 3: 1) to give 0.97 g (70% yield) of the title compound as a colorless solid.

1H-NMR (300MHz, CDCl3) : 4.64-4. 79 (m, 6H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; l9F-NMR :-120. 11 (t, 2F),-121. 54 (t, 2F),-124. 13 (m, 4F),- 155.84 (d, 2F),-157. 58 (d, 2F).

Example 6: Synthesis of tetrakis- (2, 3,5, 6, 2', 3', 4', 5', 6'-nonafluoro- biphenyl-4-oxy) methylmethane The title compound was prepared at a 58% yield in the same manner as in Example 2.

1H-NMR (300MHz, CDCl3) : 4. 86 (s, 2H, CH2) ; 19F-NMR : -137. 86 (d, 2F), -138. 90 (t, 2F), -150. 24 (t, 1F), 156.22 (d, 2F), -160. 85 (t, 2F) Example 7:

Synthesis of tetrakis- {4'- [6- (2-tetrahydro-pyranyloxy)- 2, 2, 3, 3, 4, 4, 5, 5,6, 6-octafluorohexyloxy]-2, 3,5, 6,2', 3', 5', 6'- octafluoro-(4-biphenoxy) methyl} methane The title compound was prepared at a 92% yield in the same manner as in Example 3.

1H-NMR (300MHz, Acetone-d6) 2.98 (s, OH), 4.17 (t, 2H), 5.02- 5.15 (m, 4H) ; 19F-NMR (300 MHz, Acetone-d6) : -122. 02 (t, 2F), - 122.93 (t, 2F),-124. 51 (m, 4F), -141. 20 (m, 4F),-157. 10 (d, 2F),-157. 78 (d, 2F).

Example 8: Synthesis of tetrakis- [4'- (6-hydroxy-2, 2,3, 3,4, 4,5, 5- octafluorohexyloxy)-2, 3,5, 6, 2', 3', 5', 6'-octafluoro-(4-biphenoxy) methyl] methane The title compound was prepared at a 92% yield in the same manner as in Example 4.

1H-NMR (300MHz, Acetone-d6) : 2.9 (s, OH), 4.08#4. 19 (d, 2H), 5. 02#5. 16 (m, 4H); 19F-NMR : -122. 02 (t, 2F), -122. 93 (t, 2F),- 124.51 (d, 4F), -141. 25 (d, 2F), -141. 4 (d, 2F), -157. 03 (d, 2F),- 157.8 (d, 2F) Example 9: Synthesis of tetrakis [4'-(6-acryloxy- 2, 2, 3,3, 4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6, 2', 3', 5', 6'- octafluoro- (4-biphenoxy) methyl] methane (T8F8A) The title compound was prepared at a 50% yield in the same

manner as in Example 5.

1H-NMR (300MHz, CDCl3) : 4.56 (s, 2H, CH2), 5. 97-6.00 (d, J=10 Hz, 1H), 6. 14-6. 24 (dd, J=17, 10 Hz, 1H), 6. 50-6. 56 (d, J=17 Hz, 1H) ; 19F-MMR : -120. 24 (t, 2F),-121. 56 (t, 2F),-124. 22 (m, 4F),- 138.96 (t, 2F), -139. 38 (t, 2F),-156. 08 (d, 2F), -156. 79 (d, 2F).

Example 10: Synthesis of tetrakis- [2, 3,5, 6-tetrafluoro- (4- pentafluorophenyloxy)-phenoxy] methylmethane The title compound was prepared at a 50% yield in the same manner as in Example 2.

1H-NMR (300MHz, CDC13) : 4.56 (s, 2H, CH2) ; 19F-NMR : -158. 8 (d, 2F), -159. 3 (d, 4F), -162. 26 (t, 1F),-162. 86 (t, 2F) Example 11: Synthesis of tetrakis-14'- [6- (2-tetrahydro- pyranyloxy)-2, 2,3, 3,4, 4,5, 5,6, 6-octafluorohexyloxy]-2, 3,5, 6- tetrafluoro- (4-tetrafluorophenyloxy)-phenoxymethyl}methane The title compound was prepared at a 90% yield in the same manner as in Example 3.

1H-NMR (300MHz, CDCl3) : 1. 53-1. 84 (m, 6H), 3.57 (t, 1H), 3.79 (m, 1H), 3.96 (t, 1H), 4. 75 (m, 4H), 4. 76 (d, 1H) ; 19F-NMR : - 121.2 (s, 2F), -121. 9 (s, 2F),-122. 1 (d, 4F), -157. 17 (d, 2F),- 157.65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 12: Synthesis of tetrakis- [4'- (6-hydroxy-

2,2, 3,3, 4,4, 5,5, 6,6-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenyloxy)-phenoxymethyl] methane The title compound was prepared at a 92% yield in the same manner as in Example 4.

1H-NMR (300MHz, Acetone-d6) : 4. 05#4. 12 (m, 2H), 4. 67-4. 84 (m, 3H), 5.12 (t, 1H) ; 19F-NMR :-122. 1 (d, 2F),-123. 07 (d, 2F),- 124.74 (d, 4F), -121. 2 (s, 2F), -121. 9 (s, 2F),-122. 1 (d, 4F),- 157.17 (d, 2F),-157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 13: Synthesis of tetrakis-[4' - (6-acryloxy- 2,2, 3, 3, 4,4, 5, 5-octafluorohexyloxy)-2, 3, 5, 6-tetrafluoro- (4- tetrafluorophenyloxy) -phenoxymethyl] methane The title compound was prepared at a 70% yield in the same manner as in Example 5.

1H-NMR (300MHz, CDC13): 4. 64-4. 79 (m, 6H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR :-119. 8 (t, 2F),-121. 9 (t, 2F),-123. 92 (d, 4F),- 138. 5 (d, 2F),-138. 87 (d, 2F), -155. 69 (d, 2F), -156. 38 (d, 2F),- 157., 17 (d, 2F),-157. 65 (d, 2F) Example 14: Synthesis of tetrakis- [2, 3,5, 6-tetrafluoro- (4- pentafluorophenylsulfanyl)-phenoxy] methylmethane The title compound was prepared at a 40% yield in the same manner as in Example 2.

1H-NMR (300MHz, CDC13) : 4.56 (s, 2H, CH2) ; 19F-NMR :-158. 8 (d,

2F), -159. 3 (d, 4F), -162. 26 (t, 1F), -162. 86 (t, 2F) Example 15 : Synthesis of tetrakis-{4'-[6-(2-tetrahydro- pyranyloxy)-2, 2, 3, 3, 4, 4,5, 5,6, 6-octafluorohexyloxy]-2, 3, 5,6- <BR> <BR> <BR> <BR> <BR> tetrafluoro- (4-tetrafluorophenylsulfanyl)-phenoxymethyl} methane The title compound was prepared at a 97% yield in the same manner as in Example 3.

1H-NMR (300MHz, CDC13) : 1. 53-1. 84 (m, 6H), 3. 57 (t, 1H), 3. 79 (m, 1H), 3.96 (t, 1H), 4.75 (m, 4H), 4.76 (d, 1H) ; 19F-NMR : - 121.2 (s, 2F),-121. 9 (s, 2F),-122. 1 (d, 4F),-157. 17 (d, 2F),- 157.65 (d, 2F),-158. 8 (d, 2F), -159. 3 (d, 2F) Example 16 : Synthesis of tetrakis- [4'- (6-hydroxy- 2,2, 3,3, 4,4, 5,5, 6, 6-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenylsulfanyl)-phenoxymethyl] methane The title compound was prepared at a 92% yield in the same manner as in Example 4.

1H-NMR (300MHz, Acetone-d6) : 4. 05-4. 12 (m, 2H), 4. 67-4. 84 (m, 3H), 5.12 (t, 1H) ; 19F-NMR : -122. 1 (d, 2F),-123. 07 (d, 2F),- 124.74 (d, 4F), -121. 2 (s, 2F),-121. 9 (s, 2F),-122. 1 (d, 4F),- 157.17 (d, 2F), -157. 65 (d, 2F),-158. 8 (d, 2F),-159. 3 (d, 2F) Example 17: Synthesis of tetrakis- [4'- (6-acryloxy- 2,2, 3,3, 4,4, 5,5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenylsulfanyl)-phenoxymethyl] methane

The title compound was prepared at a 70% yield in the same manner as in Example 5.

1H-NMR (300MHz, CDCl3) : 4. 55#4. 71 (m, 6H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17,10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -119. 8 (t, 2F), -121. 9 (t, 2F), -123. 92 (d,. 4F), - 138. 5 (d, 2F),-138. 87 (d, 2F),-155. 69 (d, 2F),-156. 38 (d, 2F), - 157.17 (d, 2F),-157. 65 (d, 2F) Example 18 : Synthesis of tetrakis- [2, 3,5, 6-tetrafluoro- (4- pentafluorobebzenesulEonyl)-phenoxy] methylmethane The titl compound was prepared at a 40% yield in the same manner as in Example 2.

1H-NMR (300MHz, CDC13) : 4.56 (s, 2H, CH2) ; l9F-NMR : -158. 8 (d, 2F), -159. 3 (d, 4F),-162. 26 (t, 1F),-162. 86 (t, 2F) Example 19: Synthesis of tetrakis-{4'-[6-(2-tetrahydro- pyranyloxy)-2, 2,3, 3,4, 4,5, 5,6, 6-octafluorohexyloxy]-2, 3, 5,6- <BR> <BR> <BR> <BR> <BR> tetrafluoro- (4-tetrafluorobenzenesulfonyl)-phenoxymethyl} methane The title compound was prepared at a 97% yield in the same manner as in Example 3.

1H-NMR (300MHz, CDCl3) : 1. 53-1. 84 (m, 6H), 3.57 (t, 1H), 3.79 (m, 1H, 3.96 (t, 1H), 4.75 (m, 4H), 4.76 (d, 1H) ; 19F-NMR :-121. 2 (s, 2F),-121. 9 (s, 2F),-122. 1 (d, 4F),-157. 17 (d, 2F),-157. 65 (d, 2F),-158. 8 (d, 2F), -159. 3 (d, 2F)

Example 20: Synthesis of tetrakis- [4'- (6-hydroxy- 2, 2, 3, 4,4,5,5,6,6-octafluorohexyloxy)-2,3,5,6-tetrafluoro-(4- tetrafluorobenzenesulfonyl)-phenoxymethyl] methane The title compound was prepared at a 92% yield in the same manner as in Example 4.

1H-NMR (300MHz, Acetone-d6) 4. 05-4. 12 (m, 2H), 4. 67-4. 84 (m, 3H), 5.12 (t, 1H) ; 19F-NMR : -122. 1 (d, 2F), -123. 07 (d, 2F),- 124.74 (d, 4F), -121. 2 (s, 2F), -121. 9 (s, 2F),-122. 1 (d, 4F),- 157. 17 (d, 2F),-157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 21: Synthesis of tetrakis- [4'- (6-acryloxy- 2, 2, 3,3, 4,4, 5,5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorobenzenesulfonyl) -phenoxymethyl] methane The title compound was prepared at a 65% yield in the same manner as in Example 5.

1H-NMR (300MHz, CDCl3) : 4. 55-4. 71 (m, 6H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17,10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -119. 8 (t, 2F), -121. 9 (t, 2F),-123. 92 (d, 4F),- 138.5 (d, 2F),-138. 87 (d, 2F),-155. 69 (d, 2F),-156. 38 (d, 2F),- 157.17 (d, 2F),-157. 65 (d, 2F) Example 22: Synthesis of tetrakis- {2, 3, 5,6-tetrafluoro-4- (2,2, 3, 3, 4, 4,5, 5-octafluoro-6-hexyloxy)-phenoxy} methylmethane The title compound was prepared at a 42% yield in the same

manner as in Example 2.

H-NMR (300MHz, CDC13) : 4.56 (s, 2H, CH2); 19F-NMR: -121. 2 (s, 2F),-121. 9 (s, 2F), -122.1 (d, 4F), -157. 17 (d, 2F),-157. 65 (d, 2F),-158. 8 (d, 2F),-159. 3 (d, 2F) Example 23: Synthesis of tetrakis-{4'-[6-(2-tetrahydro- pyranyloxy)-2, 2, 3,3, 4, 4, 5, 5, 6, 6-octafluorohexyloxy]-2, 3, 5, 6- tetrafluoro-4- (2, 2,3, 3,4, 4,5, 5-octafluoro-6-hexyloxy)- phenoxymethyl} methane The title compound was prepared at a 97% yield in the same manner as in Example 3.

1H-NMR (300MHz, CDCl3) : 1.53#1. 84 (m, 12H), 3. 57 (t, 2H), 3.79 (m, 2H), 3.96 (t, 2H), 4.75 (m, 8H), 4. 7'6 (d, 2H) ; 19F-NMR : - 121.2 (s, 4F), -121. 9 (s, 4F),-122. 1 (d, 8F), -157. 17 (d, 2F),- 157.65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 24: Synthesis of tetrakis- [4'- (6-hydroxy- 2, 2,3, 3,4, 4,5, 5,6, 6-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro-4- (2,2, 3,3, 4,4, 5, 5-octafluoro-6-hexyloxy) -phenoxymethyl] methane The title compound was prepared at a 90% yield in the same manner as in Example 4. lH-NMR (300MHz, Acetone-d6) : 4. 05#4. 12 (m, 2H), 4. 67-4. 84 (m, 6H), 5.12 (t, 2H); 19F-NMR : -121. 2 (s, 4F), -121. 9 (s, 4F),-122. 1 (d, 8F), -157. 17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F), 159.3 (d, 2F)

Example 25: Synthesis of tetrakis- [4- (6-acryloxy- 2,2,3, 3, 4,4,5,5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro-4- (2,2, 3,3, 4, 4r5, 5-octafluoro-6-hexyloxy)-phenoxymethyl] methane The title compound was prepared at a 65% yield in the same manner as in Example 5.

1H-NMR (300MHz, CDCl3) : 4. 55-4. 71 (m, 10H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17,10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -120. 08 (t, 4F), -121. 9 (t, 4F),-124. 1 (d,. 8F), - 157. 1 (d, 2F), -157. 6 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 26 : 4,4'-bis (6-hydroxy-2,2, 3,3, 4,4, 5,5- octafluorohexyloxy)-2, 3,5, 6, 2', 3', 5', 6'-octafluorobiphenyl Under a nitrogen stream in a round-bottom flask, 5 g (19. 1 mmol) of 2,2, 3,3, 4,4, 5, 5-octafluoro-1, 6-hexanediol and 13.7 g (41.9 mmol) of cesium carbonate were dissolved in 150 ml of anhydrous dimethylformamide, to which 12.7 g (38.1 mmol) of decafluorobiphenyl was added. The solution was stirred for 20 hours at room temperature. After completion of the reaction as indicated by TLC, the reaction solution was distilled under reduced pressure to remove the solvent, added with distilled

water (30 ml), extracted with ethyl acetate (50 ml x 2), dried with'anhydrous MgS04 and filtered. The filtrate was distilled under vacuum, and the product was purified by column chromatography (hexane : ethyl acetate = 3 : 1) to give 14.6 g (90% yield) of the title compound as a white solid. lH-NMR (300MHz, CDC13) : 3.94 (m, 2H), 4.63 (s, OH), 4.72 (m, 2H) ; 19F-NMR (300 MHz, CDC13) : -121. 64 (t, 2F),-122. 85 (t, 2F), - 124. 36 (m, 4F), -141. 20 (t, 4F), -157. 05 (d, 4F).

Example 27 : Synthesis of 4, 4'-bis (6-acryloxy- 2,2, 3, 3,4, 4,5, 5-octafluorohexyloxy) -2, 3,5, 6, 2', 3', 5', 6'- octafluorobiphenyl (B4F8FA) The title compound was prepared at an 80% yield in the same manner as in Example 5.

1H-NMR : H-NMR (300MHz, CDC13) : 4.61-4. 79 (m, 4H), 5.94-5. 97 (d, J=10 Hz, 1H), 6.13-6. 23 (dd, J=17, 10 Hz, 1H), 6.47-6. 52 (d, J=17 Hz, 1H) ; 19F-NMR (300 MHz, CDC13):-120. 05 (t, 2F), -121. 32 (t, 2F), -123. 92-124.15 (m, 4F), -138. 57 (t, 4F),-155. 67 (d, 4F).

Example 28 : Synthesis of 4, 4'-bis (6-hydroxy- 2,2, 3,3, 4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenyloxy) phenyl The title compound was prepared at an 85% yield in the same

manner as in Example 26.

1H-NMR (300MHz, (CDCl3) : 3.94 (m, 2H), 4.63 (s, OH), 4.72 (m, 2H) ; 19F-NMR : -121. 64 (d, 2F), -122. 85 (d, 2F), -124. 36 (d, 4F),- 157.17 (d, 2F), -157. 65 (d, 2F),-158. 8 (d, 2F),-159. 3 (d, 2F) Example 29 : Synthesis of 4, 4'-bis (6-acryloxy- 2,2, 3,3,4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenyloxy) phenyl . The title compound was prepared at an 80% yield in the same manner as in Example 5.

1H-NMR : H-NMR (300MHz, CDC13) : 4. 61-4. 79 (m, 4H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -120. 05 (t, 2F), -121. 32 (t, 2F),- 123. 92-124. 15 (d 4F),-157. 17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 30 : Synthesis of 4,4'-bis (6-hydroxy- 2,2, 3,3, 4,4, 5,5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorophenylsulfanyloxy) phenyl The title compound was prepared at an 85% yield in the same manner as in Example 26.

H-NMR (300MHz, CDC13) : 3. 94 (m, 2H), 4.63 (s, OH), 4.72 (m, 2H) ; 19F-NMR : -121. 64 (d, 2F),-122. 85 (d, 2F),-124. 36 (d, 4F),- 157.17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F)

Example 31: Synthesis of 4, 4'-bis (6-acryloxy- 2, 2, 3, 3,4, 4, 5, 5-octafluorohexyloxy)-2, 3, 5, 6-tetrafluoro- (4- tetrafluorophenylsulfanyloxy) phenyl The title compound was prepared at an 80% yield in the same manner as in Example 5.

1H-NMR : H-NMR (300MHz, CDCl3) : 4. 61-4. 79 (m, 4H), 5.97-6. 00 (d, J=10 Hz, 1H),'6. 14-6.24 (dd, J=17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -120. 05 (t, 2F),-121. 32 (t, 2F),- 123. 92-124. 15 (d, 4F),-157. 17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F),-159. 3 (d, 2F) Example 32 : Synthesis of 4, 4'-bis (6-hydroxy- 2,2, 3,3, 4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4- tetrafluorobenzenesulfonyloxy) phenyl The title compound was prepared at an 85% yield in the same manner as in Example 26.

1H-NMR (300MHz, CDCl3) : 3. 94 (m, 2H),. 4.63 (s, OH), 4.72 (m, 2H) ; l9F-NMR :-121. 64 (d, 2F), -122. 85 (d, 2F), -124. 36 (d,. 4F), - 157.17 (d, 2F),-157. 65 (d, 2F),-158. 8 (d, 2F), -159. 3 (d, 2F) Example 33 : Synthesis of 4, 4'-bis (6-acryloxy- 2,2, 3,3, 4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro- (4-

tetrafluorobenzenesulfonyloxy) phenyl The title compound was prepared at an 80% yield in the same manner as in Example 5.

1H-NMR : H-NMR (300MHz, CDCl3) : 4. 61-4. 79 (m, 4H), 5.97-6. 00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J==17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -120. 05 (t, 2F), -121. 32 (t, 2F),- 123. 92-124. 15 (d, 4F), -157. 17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 34 : Synthesis of 4, 4'-bis (6-hydroxy- 2,2, 3,3, 4,4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro-4- (2,2, 3,3, 4,4, 5,5-octafluoro-6-hexyloxy) phenyl The title compound was prepared at an 85% yield in the same manner as in Example 26.

1H-NMR (300MHz, CDCl3) : 3.94 (m, 4H), 4.1 (m, 4H), 4.63 (s, OH), 4.72 (m, 4H) ; 19F-NMR : -121. 64 (d, 6F), -122. 85 (d, 6F),-124. 36 (d, 12F),-157. 17 (d, 2F),-157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 35 Synthesis of 4,4'-bis (6-acryloxy- 2,2, 3, 3,4, 4, 5, 5-octafluorohexyloxy)-2, 3,5, 6-tetrafluoro-4- (2,2, 3, 3, 4, 4,5, 5-octafluoro-6-hexyloxy) phenyl The title compound was prepared at an 80% yield in the same manner as in Example 5.

1H-NMR : H-NMR (300MHz, CDC13) : 4. 61-4. 79 (m, 14H), 5. 97-6.00 (d, J=10 Hz, 1H), 6.14-6. 24 (dd, J=17, 10 Hz, 1H), 6.50-6. 56 (d, J=17 Hz, 1H) ; 19F-NMR : -121. 64 (d, 6F), -122. 85 (d, 6F), -124. 36 (d, 12F), -157. 17 (d, 2F), -157. 65 (d, 2F), -158. 8 (d, 2F), -159. 3 (d, 2F) Example 36 : Synthesis of copolymer by photocrosslinking and thermal curing Copolymers of T4F8A/B4F8FA and T8F8A/B4F8FA were synthesized in the presence of a photoinitiator at various monomer molar ratios (10 : 90, 20 : 80,30 : 70,50 : 50,70 : 30 and 80 : 20). As the photoinitiator, 1 wt% of TA2-107 [2-benzo- (1, 3) dioxol-5-yl-4, 6-bis-trichloromethyl-(1, 3, 5) triazine3 was used. The monomers were dissolved in PGMEA (propyleneglycol monoethyletheracetate) of an amount corresponding to 80 wt% relative to the total weight of the monomers, and the. mixture was filtered through a thin film filter of Teflon. The resulting solution was spin-coated on a silicon wafer at a speed of 1,100 rpm for 30 seconds, and the coated thin film was left to stand in a vacuum oven for 12 hours to remove the solvent. The remaining thin film was preheated for 10 minutes at 80 °C, cured in a 100W/cm mercury lamp UV curing system at a speed of 1 m/min, and thermally cured in a 250 °C oven for 2 hours.

The structure of the copolymers synthesized by the photocrosslinking was analyzed by an FR-IR spectrometer. As

shown in FIG. 1, the comparison of FT-IR spectrum between the monomer mixture (a), the photoinitiator (b) and the thermal crosslinked copolymer (c) (which are sequentially shown from downward to upward on the figure) indicated that, in the case of the copolymer of T4F8A/B4F8FA with a monomer molar ratio of 70: 30, the band at 1650 cm-1 by CH-stretching of the ethylene group of the monomers was remarkably reduced, and the conversion of the copolymer was 90%.

Furthermore, in order to examine the optical and thermal properties of the photocrosslinked copolymers, the refractive index and birefringence of the photocrosslinked perfluorinated copolyacrylate thin films having various monomer molar ratios were measured with a PCA-200 prism coupler at a wavelength of 1,550 nm. The results are given in Table below. The refractive index wp., s in a range from 1.441 to 1.400, and the birefringence of the typical copolymer (T4F8A/B4F8A=2 : 8) was 0.0002. In - adjusting the birefringence of the copolyacrylates, the molar ratio between the monomer T4F8A or T8F8A and the monomer B4F8FA was important, and as the molar ratio of the monomer B4F8FA to the monomer T4F8A or T8F8A was increased, the birefringence of the resulting polyacrylates was reduced. Moreover, the thermal stability of the synthesized copolymers was analyzed with a thermogravimetric analyzer (TGA) in a nitrogen atmosphere. The initial decomposition temperature (Td) of the copolymer was mostly measured to be 360 °C or above. The glass transition temperature (Tg) of the copolymer was not measured.

Table : Photocrosslinking of UV-curable multifunctional perfluorinated acrylic monomers

- Td Td C) d nTE nTM nTE-TM (7 : 1. 4423 1. 4387 0. 0035 (2 4336 1. 4334 0. 0002 (7 : 4128 0. 0012 (2 8) 4401 1. 4404 0. 0003 (@ 1550nm)aT4F8FA/B4F8FA, bT8F8FA/B4F8FA, CFrom DSC thermograms measured in N2, d5 o weight loss, N2 . Furthermore, as shown in FIG. 2, the comparison of the absorption spectrum in the near infrared region (NIR) between polymethylmethacrylate (PMMA) and the photocrosslinked fluorinated copolyacrylates indicated that the copolyacrylates had low absorbance at wavelengths of 1,300 nm and 1,550 nm.

Example 37: Synthesis of monomers for binders Synthesis of 2, 2,3, 3,4, 4,5, 5-octafluoro-6- (2,3, 5,6, 2', 3', 4', 5', 6'-nonafluoro-biphenyl-4-yloxy)-hexane-1-ol Under a nitrogen stream in a round-bottom flask, 6.0 g (22.9 mmol) of 2,2, 3, 3,4, 4, 5, 5-octafluoro-1, 6-hexanediol and

1.58 g (11.4 mmol) of potassium carbonate were dissolved in 60 ml of anhydrous dimethylformamide, to which 3.82 g (11.4 mmol) of decafluorobiphenyl was added. The solution was stirred for 24 hours at room temperature. After completion of the reaction as indicated by TLC, the reaction solution was distilled under reduced pressure to remove the solvent, added with 30 ml of distilled water, extracted with ethyl acetate (50 ml x 2), dried with anhydrous MgS04 and filtered. The filtrate was distilled under reduced pressure, and the product was purified by column chromatography (hexane : ethyl acetate = 3 : 1) to give 3.0 g (46% yield) of the title compound as a white solid.

1H-NMR (300MHz, CDC13) : 4.0-4. 1 (m, 2H), 5.01-5. 11 (t, 2H); 9F-NMR (300 MHz, CDC13) : -122. 0 (t, 2F), -123. 0 (t, 2F),- 124.53-124. 73 (d, 4F), -140. 59 (m, 2F), -141. 07-141.17 (m, 2F). - 152.93 (t, 1F),-156. 89 (d, 2F), -163. 11-163.30 (dt, 2F) Synthesis of 2, 2,3, 3,4, 4,5, 5-octafluoro-6- (2,3, 5,6, 2', 3', 4', 5', 6'-nonafluoro-biphenyl-4-yloxy)-hexyl acrylate Under a nitrogen stream, 1.0 g (1.69 mmol) of 2, 2,3, 3,4, 4,5, 5-octafluoro-6- (2, 3,5, 6,2', 3', 4', 5', 6'-nonafluoro- biphenyl-4-yloxy)-hexan-l-ol was dissolved in 20 ml of dichloromethane, to which 0.47 ml (3.38 mmol) of triethylamine was added. The solution was stirred for 30 minutes at room

temperature, to which 0.18 ml (2.19 mmol) of acryloyl chloride was then slowly added dropwise in an ice bath. After completion of the reaction as indicated by TLC, the reaction solution was distilled under reduced pressure'to remove the dichloromethane, and the product was dissolved in 20 ml of chloroform, washed with distilled water (50 ml x 2), dried with anhydrous magnesium sulfate and filtered. The filtrate was distilled under reduced pressure, and the product was purified by column chromatography (hexane : ethyl acetate = 3 : 1) to give 0.74 g (70% yield) of the title compound as colorless oil.

1H-NMR (300MHz, CDC13) : 5 4.82-4. 91 (t, 2H), 5.09-5. 18 (t, 2H), 6.05-6. 09 (d, J=10 Hz, 1H), 6.21-6. 30 (dd, J=17, 10 Hz, 1H), 6.46-6. 53 (d, J=17 Hz, 1H) ; 19F-NMR (300 MHz, CDC13) : 5-122. 50 (t, 2F), -121. 93 (t, 2F),-124. 35-124.64 (d, 4F),-139. 98- 140.06 (m, 2F), -141. 04-141.13 (m, 2F). -152. 95 (t, 1F),-156. 89 (d, 2F), -163. 15-163.28 (dt, 2F) Example 38: Synthesis of binder polymer (F9BPH-HPP) I In a flask dried under vacuum, 1.0 g (0. 79' mmol) of 2, 2,3, 3,4, 4,5, 5-octafluoro-6- (2, 3,5, 6,2', 3', 4', 5', 6'-nonafluoro- biphenyl-4-yloxy)-hexyl acrylate and 2-hydroxy-3-phenoxy propyl acrylate were dissolved in 3 ml of anhydrous benzene under a nitrogen stream, to which 5 mg of azobisisobutyronitrile was added. The solution was left to stand at 70 °C for 50 hours.

The reactor was cooled and the reaction solution was precipitated in an excess of methyl alcohol. The produced precipitate was dried under vacuum, and its weight was measured to calculate polymerization yield. 1.0 g (83% yield) of the polymer (F9BPH-HPP) was obtained. The content ratio of the monomers in the synthesized polymer was calculated by measuring the area ratio between the monomer peaks of lH-NMR. The result indicated that the monomers in the polymers were quantitatively polymerized at a molar ratio of 1: 1. The synthesized polymer had a number-average molecular weight of 5.7 x 104 (g/mol) and a molecular weight distribution of 4.0-4. 9.

1H-NMR (300MHz, CDC13) : 7.18 (2H), 6.88 (3), 5.06 (2H), 4.72 (2H), 4.19 (3H), 3.99 (2H), 2.68 (2H), 1.67 (4H) ; 19F-NMR : -120. 53 (2F),- 121. 88 (2F),-124. 62 (4F), -140. 01 (2F),-141. 06 (2F),-152. 90 (1F), - 156. 93 (2F),-163. 17 (2F) Example 39: Synthesis of binder polymer (F9BPH-HPP) II with reactivity Under a nitrogen stream, 1.0 g of binder polymer (F9BPH- HPP) I was dissolved in a solvent mixture of 20 ml dichloromethane and 2 ml pyridine, to which 0.15 ml of acryloyl chloride was then slowly added dropwise. The solution was stirred for 12 hours at room temperature. The reaction solution was put in an excess of methanol, stirred in an ice bath for one

hour. Then, the methanol layer was separated, to which 50 ml of a mixed solution (1: 1) of ethyl acetate and hexane was added.

The solution was stirred for one hour at room temperature. The produced precipitate was removed by filter paper, and the filtrate was freeze-dried to give 0.7 g (70% yield) of the binder polymer (F9BPH-HPP) II having reactivity. The synthesized polymer had a molecular weight of 7.3 x 104 (g/mol) and a molecular weight distribution of 3.1-3. 4. Furthermore, the thermal stability of the synthesized polymer was analyzed with a thermogravimetric analyzer (TGA) under a nitrogen atmosphere.

The initial decomposition temperature (Td) of the polymer was mostly measured to be 350 °C or above, which indicates excellent thermal stability.

1H-NMR (300MHz, CDC13) 5 1.67 (4H), 2.68 (2H), 3.99 (2H), 4.19 (3H), 4.72 (2H), 5.06 (2H), 5.55-5. 67 (1H), 5.82-6. 20 (1H), 6. 31-6. 39 (1H) ; 19F-NMR : -120. 53 (2F),-121. 88 (2F), -124. 62 (4F),- 140. 01 (2F), -141. 06 (2F), -152. 90 (1F), -156. 93 (2F), -163. 17 (2F) Example 40: Synthesis of binder polymer (HBP) III In a flask dried under vacuum, 1.0 g (0.79 mmol) of 2,2, 3,3, 4,4, 5, 5-octafluoro-6- (2, 3,5, 6, 2', 3', 4', 5', 6'-nonafluoro- biphenyl-4-yloxy)-hexyl acrylate was dissolved in 3 ml of anhydrous benzene under a nitrogen stream, to which 5 mg of azobisisobutyronitrile was added. The solution was left to stand at 70 °C for 50 hours. The reactor was allowed to cool and the

reaction solution was precipitated in an. excess of methyl alcohol. The produced precipitate was filtered and dried under vacuum, and then its weight was measured to calculate the polymerization yield. 0.9 g (90% yield) of the binder polymer (HBP) was obtained. The synthesized polymer had a number-average molecular weight of 3.3 x 104 (g/mol) and a molecular weight distribution of 3.1. Furthermore, the thermal stability of the polymer was examined with a thermogravimetric analyzer (TGA), and the result showed the polymer had excellent thermal stability at a temperature of less than 350 °C.

1H-NMR (300MHz, CDC13) : 5.00-5. 09 (2H), 4.74-4. 82 (2H), 4.19 (3H), 3.99 (2H), 2.68 (1H), i. 68 (2H) ; 19F-NMR : -120. 53 (2F),- 121.88 (2F),-124. 62 (4F), -140. 01 (2F),-141. 06 (2F), -152. 90 (1F), - 156. 93 (2F), -162. 17 (2F) Example 41: Synthesis of photocrosslinked copolymer using binder polymer (HBP) III A copolymer of polymer HBP III and a monomer mixture (T8F8A/B4F8FA) was synthesized in the presence of a photoinitiator while changing the weight ratio between the HBP III and the monomer mixture (T8F8A/B4F8FA) from 20: 80 to 30: 70, 50: 50,70 : 30 and 80: 20. The molar ratio between the monomers T8F8A and B4F8FA was 50: 50, and as the photoinitiator, 1 wt% of 2-benzo- (1, 3) dioxol-5-yl-4, 6-bis-trichloromethyl- (1, 3,5) triazine

(TA2-107) was used. The polymer and monomers were dissolved in chlorobenzene of an amount corresponding to 80 wt% relative to the total weight of the polymer and monomers, and the mixture was filtered through a thin film filter of Teflon. The resulting solution was spin-coated on a silicon wafer at a speed of 1,100 rpm for 30 seconds, and the coated thin film was left to stand in a vacuum oven for 12 hours to remove the solvent. The remaining thin film was preheated for 10 minutes at 80 °C, cured in a 100W/cm mercury lamp UV curing system at a speed of, 1 m/min, and thermally cured in a 250 °C oven for 2 hours.

In order to examine the structure of the photocrosslinked copolymer, the synthesized copolymer was analyzed by an FR-IR spectrometer. The result showed that the band at 1650 cm~1 by CH-stretching of the ethylene group of the monomers was remarkably reduced, and the polymerization conversion was more than 90%.

Furthermore, in order to examine the optical and. thermal properties of the photocrosslinked copolymer, the photocrosslinked perfluorinated copolyacrylate of 50wt% HBP III and 50 wt% monomer mixture (T8F8A/B4F8FA) (50: 50 monomer molar ratio) was measured for its physical properties. The refractive index and birefringence of the copolymer thin film were measured using a PCA-200 prism coupler at a 1,550 nm wavelength. The results showed that the copolymer thin film had a TE mode refractive index of 1.4468, a TM mode refractive index of 1.4563,

and a birefringence of 0.0005. Thus, it could be found that the copolyacrylate containing no binder polymer (HBP) III had a birefringence of 0.0017 whereas the copolyacrylate containing the binder polymer (HBP) III had a reduced birefringence of 0.0005. Moreover, the thermal stability of the synthesized copolymers was analyzed with a thermogravimetric analyzer (TGA) under a nitrogen analyzer. The initial decomposition temperature (Td) of the copolymers was mostly measured to be above 390 °C, which indicates excellent thermal stability.

Industrial Applicability As described above, the present invention provides a variety of the fluorinated acrylate monomers and polymers, which satisfy properties required for low-loss optical waveguide materials and are used. to develop new UV-curable polyacrylate compounds.

The fluorinated polyacrylate compounds synthesized by the present invention have the following effects. Namely, they show minimized optical loss in the near-infrared region, since they contain fluorine. Also, they have low birefringence caused by the fine control of refractive index. Moreover, by virtue of the aromatic compound introduced into their molecule, they show increased thermal stability and allow a device fabrication process to be simplified by UV-curing.

In addition, the inventive copolymers containing the binder polymer have various advantages, such as remarkably reduced refractive index and birefringence, increased thermal stability, low optical loss, and reduced synthetic costs.