Synthesis and properties of novel polyimide optical materials with different haloid pendant

Abstract

To investigate the difference of trifluoromethyl group and chlorine group affecting the optical properties of polyimides (PIs), two diamine monomers with different haloid pendants were designed and synthesized including (1,4‐(4‐amino‐2‐trifluoromethylphenoxy)‐2‐(3′5′‐ditrifluoromethylphenyl)benzene and (1,4‐(4‐amino‐2‐trifluoromethylphenoxy)‐2‐(3′‐trifluoromethyl‐4′‐chlorophenyl) benzene). From both diamines, two series of PIs with different haloid pendants were prepared via two‐step chemical imidization methods with various dianhydride compounds. All the PIs have the high Tg, excellent thermal stability and good solubility, and can be formed the transparent, strong, and flexible films. All the PIs also are good transparent in UV‐evisible absorption spectra, and have the low birefringences (0.0128–0.0157 at 650 nm) and low optical loss at communication windows. Two series of PIs exhibit the similar optical properties, except for refractive index. Based on the fantastic characterization, a series of optical materials with the tunable refractive indices were obtained by copolymerization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

In situ preparation of transparent polyimide nanocomposite with a small load of graphene oxide

“…So, chemical imidization method was chosen in this work. Acetic anhydride (used as dehydrating agent) and triethylamine (used as catalyzer) together with GO are added to the reaction system following the production of PAA by polycondensation with the comonomers 32,33. The synthetic route is shown in Figure 1.…”

Design and synthesis of organosoluble and transparent polyimides containing bulky substituents and noncoplanar structures

“…Many efforts to chemically modify PIs have been made to overcome these weaknesses; these efforts include the introduction of bulky units or bulky pendent substituents [6][7][8][9][10][11] and the twisting of noncoplanar structures, [12][13][14][15][16] unsymmetrical structures, [17][18][19][20][21] and flexible linkages [22][23][24][25] into the polymer backbones. However, the glass-transition temperature (T g ) values of polymers containing flexible units will be greatly decreased because of the abundant flexible linkages in the macromolecular backbones.…”

Novel polyimide/graphene oxide composite films with ultralow dielectric constants

“…As shown in Figure , the PIs were prepared by a conventional two‐step polymerization method . Typically, molar equivalents (0.001 mol) of BDAPM and 6FDA were added to dried NMP with a 10% solid concentration under a nitrogen atmosphere at room temperature for 24 h. Then, GO powder was added in NMP at different mass ratios and dispersed ultrasonically for 0.5 h. The mixture was dropped into the solution prepared previously and stirred for 6 h at room temperature; this was followed by ultrasonic dispersion for 0.5 h again.…”