含硝基噁二唑聚炔的合成及三阶非线性光学性能

Synthesis and the Third-Order Nonlinear Optical Property of Oxadiazole-Containing Polyacetylene

设计合成了一种含硝基噁二唑功能基的聚炔材料。通过红外光谱(IR)和核磁共振(1H-NMR)对该聚炔化合物进行了结构表征。利用紫外光谱(UV-vis)和热重分析(TGA)对其性能进行了评价。TGA显示其热稳定性相对于单体有很大提高,UV-vis表明它在500 nm以上长波区吸收很弱。该聚炔化合物的非线性光学性能借助Z-scan技术进行研究,其χ(3)达3.25×10-11(esu)。与含烷基的同类聚炔比较,拉电子基团硝基有效地提高了含噁二唑聚炔的三阶非线性光学性能。

The oxadiazole-containing polyacetylene was synthesized in satisfactory yield with [Rh（nbd）Cl]2 catalyst.The structure and properties of the monomer and the polymer were characterized and evaluated with Fourier transform infrared spectrum（FT-IR）,1H nuclear magnetic resonance spectrum（1H-NMR）,UV-vis and thermogravimetric analysis（TGA）.The nonlinear optical property is performed with 4 ns pulse width at 532 nm wavelength.The polymer is thermally stable and the decomposed temperature is as high as ~370 ℃.The weak electronic absorption of the polymer is observed when the wavelength is over 500 nm.The result of Z-scan measurement reveals that the oxadiazole-containing polyacetylene with nitro group shows larger third order nonlinear optical susceptibility（up to 3.25×10-11esu）.