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Polymers based on N-phenyl maleimide, N-4-propargyl methoxy phenyl maleimide and methyl methacrylate was synthesized. High glass temperatures 183, 179, 159 °C respectively for P 1 , P 2 and P 3 were achieved. EO polymer P 3 –C 1 , P 3 –C 2 and P 3 –C 3 with about 30 wt% chromophore loading density were prepared by attaching Chromophore C 1 , C 2 and C 3 to polymer P 3 using copper-catalyzed Huisgen cycloaddition reactions in mild reaction conditions and high yield. Among the EO polymers, P 3 –C 3 showed us the best solubility in normal solvents and suitable glass temperature. EO films based on EO polymer P 3 –C 3 showed us large EO coefficient of 50 pm/V @1310 nm and good long-term stability, 85% EO activity was kept after annealing at 85 °C for 200 h. [ABSTRACT FROM AUTHOR]

Abstract: Two novel nonlinear optical (NLO) chromophores with 4-hydroxycarbazole as the electron donor were successfully designed and synthesized. The 4-hydroxycarbazole had two reaction sites where the isolated groups were introduced to the chromophores. The prepared chromophores were characterized by MS, 1H NMR and UV–vis spectra. Poled films of the chromophores doped in APC afforded the maximum electro-optic (EO) coefficient (r 33) of 40pm/V at 1310nm. This result was better than the similar chromophores reported using carbazole and aniline derivates as electron donor, which indicated that the introduction of isolated groups suppressed the dipole–dipole interaction between chromophores effectively and could aid the alignment of chromophores and improve the EO activity. This had been further demonstrated by the crystal structure analysis. [Copyright &y& Elsevier]

A new nonlinear optical chromophore with strong electron-withdrawing acceptor and rigid-flexible dendron was synthesized. An electro-optic (EO) attenuated total reflectance modulator was prepared to measure the EO coefficient of the films. Modification of the tricyanopyrroline chromophore with rigid-flexible dendron group provided reduction of dipole-dipole interactions and improvement of its solubility. As the chromophore loading increased, there was a great improvement on the macroscopic EO response of the polymeric materials obtained by incorporating this chromophore as a guest in amorphous polycarbonate. The largest EO coefficient was 42 pm/V at 1310 nm. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

New tricyanopyrroline (TCP) chromophores with rigid-flexible dendron were prepared for second-order nonlinear optical (NLO) application. The chromophores were fully characterized using ultraviolet-visible spectroscopy, nuclear magnetic resonance spectroscopy and mass spectrometry. Thermal gravimetric analysis (TGA) revealed that the chromophores had excellent thermal stability. Large λ and high solvate chromic effects revealed that the chromophores had large second-order optical nonlinearity. The electro-optic coefficients ( r) were measured in the chromophores-doped poly(bisphenol A carbonate) films at the fundamental wavelength of 1310 nm, and the highest γ achieved was 217 pmV. Copyright © 2010 John Wiley & Sons, Ltd. Modification of the TCP chromophore with bulky groups provides reduction of dipole-dipole interactions, thus great improvement of the macroscopic electro-optic (EO) response was achieved by incorporating these chromophores as a guest into amorphous polycarbonate (APC). Furthermore, the modificated chromophore possesses good processability and exhibits high thermal decomposition temperature. [ABSTRACT FROM AUTHOR]

Organic electro-optic (EO) materials have been widely studied and used in microwave photonic devices, due to their advantages in half-wave voltage, bandwidth, low cost and ease of integration. Nonlinear optical (NLO) chromophores, as the core of organic EO materials, can directly decide the characters of organic EO materials, including large EO activity, long term stability, solubility and optical loss. Auxiliary donors have attracted great attentions in NLO chromophores for their strong electron donating ability and significant isolation effect. This feature article describes the application of auxiliary donor in NLO chromophores, including the EO activities, optical characters, stability, crystal structures and machinability. [ABSTRACT FROM AUTHOR]

Dual D-Pi-A nunchaku-like structure chromophore was designed and synthesized to improve electro-optic (EO) materials׳ EO coefficients ( r 33 ) and long term stability by a simple doping system. The r 33 values of poled APC/10% DIMER1 and APC/20% DIMER1 are 23 pm/V and 45 pm/V respectively. After annealed at 85 °C for 500 h, the poled film of APC/20% DIMER1 can retain more than 85% of its initial r 33 value. All these characters showed us superior prospects of application in EO devices. Chromophore DIMER1 also showed us good thermal stability; its decomposition temperature (Td) was higher than 280 °C, which is enough for its application in the EO devices. Also chromophore DIMER1 had good solubility in amorphous polycarbonate (APC); it could be dissolved in APC at high loading density (25%). [ABSTRACT FROM AUTHOR]

Abstract: Novel NLO chromophore with 3, 5-bis(trifluoromethyl) benzoyl as the isolated group in electron bridge was prepared for investigating the NLO character. Chromophore FTC-wl was characterized using UV–Visible spectra, nuclear magnetic resonance, and mass spectrometry and showed us excellent thermal stability. EO films prepared by poly(bisphenol A carbonate) polymer doped with this chromophore at different content had been poled to afford the highest electro optic coefficients (r33) of 28pm/V. [Copyright &y& Elsevier]

Benchmark chromophore C1 and counterpart chromophore C2 with the same electron donor and acceptor was designed and synthesized to compare their different electro-optic coefficients and long term stability by doping system. The electro-optic coefficient of a poled film containing 25 wt% of C1 doped in amorphous polycarbonate (25 wt% C1 /APC) afforded a value of 22 pm/V at 1310 nm, while 25 wt% C2 /APC afforded a value of 60 pm/V. After annealing at 85 °C for 500 h, the poled film of 25 wt% C2 /APC could retain more than 85% of its initial r 33 value. In contrast, only 75% of the initial r 33 value of the poled film of 25 wt% C1 /APC was kept after 300 h. The excellent thermostability and its good temporal stability in APC made C2 a favorable candidate for practical application. [ABSTRACT FROM AUTHOR]

Abstracts In this work, a series of novel second order nonlinear optical chromophores modified by heteroatom-groups in electron-donor has been synthesized and systematically investigated. The resulting nonlinear optical chromophores exhibited both good thermal stability and good solubility in common organic solvents. UV–Vis spectra and density functional theory calculations were carried out to investigate the influence of heteroatom-groups on the electro-optic activities. The results revealed that increasing the electron-donor strength will not always improve the nonlinear optical activity of chromophore. There is a best match for electron-donor and acceptor. As to electro-optic activities, the doped polymer film- d3 displayed the highest electro-optic coefficient value of 37 pm/v at the doping concentration of 25 wt%. These results indicated that the nonlinear optical activities could be enhanced by finding the best match for electron-donor and acceptor in chromophore design. [ABSTRACT FROM AUTHOR]

Three novel nonlinear optical chromophores based on the same bis( N,N -diethyl)aniline donor have been synthesized and systematically characterized. These chromophores showed good thermal stability and chromophore y1 showed the best thermal stability of 249 °C. Besides, compared with the chromophore (y1) without the substituted group, chromophores y2 and y3 show better intramolecular charge-transfer absorption. Most importantly, the high molecular hyperpolarizability of these chromophores can be effectively translated into large electro-optic coefficients. The electro-optic coefficient of poled films containing 25% wt of chromophores y1–y3 doped in amorphous polycarbonate afforded values of 149, 138 and 157 pm/V at 1310 nm for chromophores y1–y3 respectively. These results indicated that the double donors of bis( N,N -diethyl)aniline unit can efficiently improve the electron-donating ability and the special structure can reduce intermolecular electrostatic interactions, thus enhancing the macroscopic electro-optic activity. These properties, together with good solubility, suggest the potential use of these chromophores as advanced materials. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel second-order nonlinear optical chromophores containing additional heteroatoms in donor moieties has been synthesized and systematically characterized. The resulting nonlinear optical chromophores exhibited both good thermal stability (the decomposition temperature in the range of 249 °C–275 °C) and good solubility in common organic solvents such as chloroform, acetone and N, N-dimethyl formamide. In order to investigate the influence of additional heteroatom on the electro-optic activities, UV–Vis spectra and density functional theory calculations were carried out. The results revealed that the donor derived from m-phenylenediamine had higher electron density compared with other three donors. As to electro-optic activities, the doped polymer film-C displayed the highest electro-optic coefficient value of 31 pm/v at the doping concentration of 20 wt%. All these results indicated that the nonlinear optical activities could be enhanced by introducing suitable additional heteroatoms into donor moiety. [Copyright &y& Elsevier]

One novel second order nonlinear optical chromophore based on benzoxazin donor and tricyanovinyldihydrofuran acceptor linked together via thiophene bridge has been synthesized and characterized. According to cyclic voltammetry measurement, chromophore Z showed low energy gap. In addition, chromophore Z displayed good thermal stability with the onset decomposition temperature over 221 °C. The electro-optic coefficient of a poled film containing 25 wt% of chromophore Z doped in polymethylmethacrylate afforded a value of 64 pm/V at 1310 nm. The result showed that chromophore Z , which had good thermal stability and high r 33 values after poling in films, was a promising candidate for practical use. [ABSTRACT FROM AUTHOR]