Polyimides with a Diazo Chromophore Exhibiting High Thermal Stability and Large Electrooptic Coefficients

Abstract

To synthesize nonlinear optical polyimides exhibiting high nonlinearity and high thermal stablity, a new monomer bearing phenylenediamine and a diazo benzene-type nonlinear optical chromophore (compound 1) was synthesized and polymerized with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride. This diazo chromophore possesses a microscopic optical nonlinearity larger than either the Disperse Red 1 or DANS chromophores. Copolymerization of compound 1 and 1,4diaminophenylene with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride yielded copolyimides with higher glass transition temperatures. These polyimides exhibit large electrooptic coefficients, r33 ∼ 14-35 pm/V. The second harmonic measurements indicate long-term stability of the dipole orientation (>800 h at 100 °C) for these polyimides.

Synthesis and Nonlinear Optical Properties of Novel Polyester with Enhanced Second Harmonic Generation Thermal Stability

“…In the developments of NLO polymers for electro-optic device applications, stabilization of electrically induced dipole alignment is one of important criteria; in this context, two approaches have been proposed to minimize the randomization of dipole alignment, namely the use cross-linking method [7][8][9][10] and the utilization of high T g polymers such as polyimides. [11][12][13][14][15][16] Various polyesters with NLO chromophores in the main chain 17 or in side chain [18][19] have been prepared and their properties studied. In general, main-chain NLO polymers have good thermal stability of dipole alignments, but they often do not dissolve in organic solvents, and their intractability make them unusable to fabricate stable films.…”

Synthesis, characterizations and electro-optical properties of nonlinear optical polyimide/silica hybrid

“…To a stirred solution of p-nitroaniline (13.8 g, 0.10 mol) in methanol/HCl (50%, V/V, 50 ml) was added sodium nitrite (6.90 g, 0.10 mol) in ice-water (15%, m/m) at 0°C [13][14][15][16]. The mixture was stirred at this temperature for 1 h. Meanwhile stirred solution of aminobenzene purified by distillation (9.3 g, 0.10 mol) in HCl (50 ml, 1 mol·l -1 ).…”

Synthesis and Properties of Novel T-type Nonlinear Optical Polyurethane Containing Tricyanovinylthienyl Group with Enhanced Thermal Stability of Dipole Alignment

“…In the developments of NLO polymers for electro-optic device applications, stabilization of electrically induced dipole alignment is one of important criteria; in this context, two approaches to minimize the randomization have been proposed, namely the use of cross-linking [7][8][9][10] and the utilization of high Tg polymers such as polyimides. [11][12][13][14][15][16] A polyurethane matrix forms extensive hydrogen bonding between urethane linkages, with increased rigidity preventing the relaxation of induced. [17][18] Polyurethanes with a NLO chromophore, whose dipole moment is aligned transverse to the main chain backbone, show large second-order nonlinearity with good thermal stability.…”