Highly fluorinated and photocrosslinkable liquid prepolymers for flexible optical waveguides
作者:Seung Koo Park、Jong-Moo Lee、Suntak Park、Jin Tae Kim、Min-su Kim、Myung-Hyun Lee、Jung Jin Ju
DOI:10.1039/c0jm02604b
日期:——
We evaluate highly fluorinated liquid prepolymers and their UV-cured films for flexible optical waveguide applications. Two liquid prepolymers, 2,3,5,6,2′,3′,5′,6′-octafluoro-4,4′-bis-[2-2-[1,1-difluoro-2-(2,3,5,6-tetrafluoro-4-vinyl-phenoxy)-ethoxy]-1,1,2,2-tetrafluoro-ethoxy}-2,2-difluoro-ethoxy]-biphenyl (7) and 2,3,5,6,2′,3′,5′,6′-octafluoro-4,4′-bis-[2-(2-2-[1,1-difluoro-2-(2,3,5,6-tetrafluoro-4-vinyl-phenoxy)-ethoxy]-1,1,2,2-tetrafluoro-ethoxy}-1,1,2,2-tetrafluoro-ethoxy)-2,2-difluoro-ethoxy]-biphenyl (8), are synthesized with decafluorobiphenyl, 2,3,4,5,6-pentafluoro styrene, and fluorinated triethylene glycol or fluorinated tetraethylene glycol. The prepolymers are photocurable to give flexible and transparent films. The refractive indices of the films made from the prepolymers are controlled with their blending composition, 1.417–1.437 at a wavelength of 1.31 μm. The optical losses of the films prepared from prepolymers 7 and 8 are 0.25 and 0.23 dB cm−1 at a wavelength of 1.31 μm, respectively. The films are thermostable at temperatures over 400 °C. The ultimate stress, initial modulus, and elongation of the films prepared from prepolymers 7 and 8 are 17.1 MPa, 1.25 GPa, and 1.5% and 12.3 MPa, 0.44 GPa, and 6.9%, respectively. Optical waveguides fabricated from the prepolymers are flexible without any substrate film and the optical losses at a bending radius of 1.5 mm are under 0.2 dB. We identify the liquid prepolymers as possible good candidate materials for flexible optical waveguide applications by studying the optical transmission in flexible optical waveguides fabricated from them.
我们对用于柔性光波导的高氟化液态预聚物及其紫外固化薄膜进行了评估。Two liquid prepolymers, 2,3,5,6,2′,3′,5′,6′-octafluoro-4,4′-bis-[2-2-[1,1-difluoro-2-(2,3,5,6-tetrafluoro-4-vinyl-phenoxy)-ethoxy]-1,1,2,2-tetrafluoro-ethoxy}-2,2-difluoro-ethoxy]-biphenyl (7) and 2,3,5,6,2′,3′,5′,6′-octafluoro-4,4′-bis-[2-(2-2-[1,1-difluoro-2-(2,2-(2-2-[1,1-二氟-2-(2,3,5,6-四氟-4-乙烯基-苯氧基)-乙氧基]-1,1,2,2-四氟-乙氧基}-1,1,2,2-四氟-乙氧基)-2,2-二氟-乙氧基]-联苯 (8) 由十氟联苯、2,3,4,5,6-五氟苯乙烯和氟化三乙二醇或氟化四乙二醇合成。这些预聚物经光固化后可形成柔韧透明的薄膜。用这些预聚物制成的薄膜的折射率受其混合成分的控制,在波长为 1.31 μm 时为 1.417-1.437。在波长为 1.31 μm 时,用预聚物 7 和 8 制备的薄膜的光学损耗分别为 0.25 和 0.23 dB cm-1。薄膜在 400 °C 以上的温度下具有热稳定性。用预聚物 7 和 8 制备的薄膜的极限应力、初始模量和伸长率分别为 17.1 兆帕、1.25 千兆帕和 1.5%,以及 12.3 兆帕、0.44 千兆帕和 6.9%。用这些预聚物制造的光波导无需任何基底膜即可弯曲,弯曲半径为 1.5 毫米时的光损耗低于 0.2 分贝。通过研究用液态预聚物制造的柔性光波导中的光传输,我们确定液态预聚物可能是柔性光波导应用的理想候选材料。