Synthesis and characterization of fluorinated polyimides for optical waveguide application

Fluorinated polyimides with high thermal stability, low optical absorption loss in the optical communication wavelengths of 1.3 and 1.55 mu m, and low birefringence and water absorption have been investigated for optical waveguide applications. These polyimides were prepared from 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) with 1,4-bis-(4-amino-2-trifluoromethyl-phenoxy) tetrafluorobenzene (ATPT), 1,4-bis-(4-amino-2-trifluoromethyl-phenoxy) benzene (ATPB), and 1,3-bis(4-amino-2-trifluoromethyl-phenoxy) 4,6-dichlorobenzene (ATPD), respectively. The polyimides obtained had glass transition temperatures that ranged from 260 to 280 degrees C, and low water absorption less than 0.4% and low optical loss (> 0.2 dB/cm) at 1.3 and 1.55 mu mu m. Birefringency values of polymer films ranged from 0.0041 to 0.0066.