Synthesis of Polymers and Oligomers for Nonlinear Optical Activity

非线性光学活性聚合物和低聚物的合成

• 批准号: 8815508
• 负责人: Larry Dalton
• 金额: $ 25.48万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-12-15 至 1991-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8815508&HistoricalAwards=false
• 关键词: Synthesis; Polymers; Oligomers; Nonlinear; Optical

By optimizing electron delocalization and intramolecular charge transfer, polymers yielding third order nonlinear optical susceptibilities in excess of 10-9 esu have been prepared as thin (1 micron) films. Figures of merit as high as 104 have been obtained for pristine materials. Doping (intermolecular charge transfer) yields even larger values in some cases. Ladder and penylpolyene materials prepared in preliminary studies also exhibit doping-induced visual transparency, i.e., bleaching of the pi-pi* interband transition and accompanying appearance of intraband (polaron/bipolaron) transitions. Electron-donating and withdrawing substituents are observed to stabilize these mid-gap state species. The reactivity of delocalized pi electron systems with molecular oxygen has been investigated and the effect of interruption of electron delocalization upon nonlinear optical activity has been demonstrated. This research focues upon further development of polymers, copolyers, and composite materials for enhanced nonlinear optical activity. Particular attention is paid to the development of air-stable materials and to correlation of data obtained for model compounds (oligomers) and polymers. Copolymers and composites of linear and nonlinear optical materials will be developed. Components will be so chosen that indices of refraction are matched at low light intensities but are mismatched at high intensities.

通过优化电子离域和分子内电荷转移，制备出了三阶非线性光学磁化率超过10-9 esu的聚合物薄膜（1微米）。原始材料的质量值高达104。掺杂（分子间电荷转移）在某些情况下产生更大的值。初步研究中制备的梯状和苯基多烯材料也表现出掺杂诱导的视觉透明度，即pi-pi*带间跃迁的漂白和带内（极化子/双极化子）跃迁的伴随出现。观察到供电子和吸电子取代基稳定了这些中隙态物质。研究了离域pi电子系统与分子氧的反应性，并证明了电子离域中断对非线性光学活性的影响。本研究的重点是进一步发展聚合物、共聚物和复合材料，以增强非线性光学活性。特别关注空气稳定材料的发展和模型化合物（低聚物）和聚合物获得的数据的相关性。线性和非线性光学材料的共聚物和复合材料将得到发展。元件的选择将使折射率在低光强下匹配，而在高光强下不匹配。