Gopalan Padma, Katz Howard E, McGee David J, Erben Chris, Zielinski Thomas, Bousquet Danielle, Muller David, Grazul John, Olsson Ylva
Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, New Jersey 07974, USA.
J Am Chem Soc. 2004 Feb 18;126(6):1741-7. doi: 10.1021/ja039768k.
Three new azo-benzene-based push-pull chromophores with dendritic architecture were synthesized as active materials for electro-optic applications. These chromophores were synthesized in six or seven synthetic steps with an overall yield of around 80% per step and high purity. UV-vis spectroscopy showed significant influence of the transient dipole moment on the observed r(33) values. The chromophores were stable to photochemical oxidation in ambient light and air. The electrical poling conditions were optimized for each chromophore as the T(g) of the composite material varied significantly. The highest EO coefficient achieved was 22-25 pm/V at 1550 nm wavelength. STEM analysis of the blends enabled the correlation of the activity of these large chromophores with the blend morphology. An amorphous polycarbonate host effectively disperses the chromophores in 2-20 nm aggregates in the active materials. However, macrophase separation into 200-500 nm aggregates was observed in a methacrylate host matrix.
合成了三种具有树枝状结构的新型基于偶氮苯的推拉型发色团，作为电光应用的活性材料。这些发色团通过六步或七步合成，每步总产率约为80%，且纯度较高。紫外-可见光谱表明，瞬态偶极矩对观测到的r(33)值有显著影响。这些发色团在环境光和空气中对光化学氧化稳定。由于复合材料的玻璃化转变温度（T(g)）变化显著，针对每个发色团优化了电场极化条件。在1550 nm波长下实现的最高电光系数为22 - 25 pm/V。对共混物的扫描透射电子显微镜（STEM）分析能够将这些大型发色团的活性与共混物形态相关联。无定形聚碳酸酯主体有效地将发色团分散在活性材料中形成2 - 20 nm的聚集体。然而，在甲基丙烯酸酯主体基质中观察到形成了200 - 500 nm的宏观相分离聚集体。
