偶氮苯取代功能聚炔(poly(PBNAA))的制备及光限幅性能

Preparation and optical limiting properties of functional polyacetylene (poly(PBNAA))

使用二环己基碳酰亚胺(DCC)和N,N-二甲基吡啶(DMAP)催化酯化合成了非线性取代炔化合物3-{4-[4′-硝基-偶氮苯-4-[N-甲基-N-亚乙氧基羰基]苯氧基]-1-丙炔(PBNAA),在金属铑催化剂作用下制备出偶氮取代功能聚炔。用紫外、红外、核磁和元素分析对材料的结构进行表征,并测定了其光限幅性能。发现高分子溶液对脉宽40ps波长1064nm激光,在低入射激光光强时,透射光强度随入射光强度增加而增加;对浓度为0.6×103mg/L溶液当入射光强度达105.4GW/cm2透射光强开始偏离线性光限幅阈值,随着入射光强进一步增加到491.2GW/cm2时,透射光强逐渐达到一个饱和值(197.8GW/cm2)。并发现随着溶液浓度增加,光限幅性能增强。对光限幅机制的分析显示,材料对1064nm波长激光的限幅机制主要是双光子吸收机制。

The nonlinear optical chromophoric group substituted acetylene, 3 {4-[4＇-nitro-azobenzene-4-（N-meth- yl, N-ethenoxy carbonyl）-lbenzene-oxy}-l-propyne （PBNAA）, was synthesized using 1,3-dicyclohexylcarbodiimide and p-dimethyaminopyridine as catalysts and polymerized by [Rh（nbd）Cl]2 as catalyst. A functional polyacetylene （poly（PBNAA）） with high molecular weight was prepared. Its optical limiting property of poly（PBNAA） in THF solution was studied. In the low fluence region, the poly （PBNAA） solution with a concentration of 0. 60 × 10^3mg/L exhibites a high linear transmittance （78%） and the transmitted fluence linearly increases with the incident fluence. In the high fluence （105. 4GW/cm^2）. With further increasing the incident fluence, the transmitted fluence reaches a plateau and saturated at 197.8GW/cm^2. Simutaneously, it is found that the optical limiting properties was enhanced with the increase of solution concentration. The limiting mechanism of poly（PBNAA） was investigated, showing that the optical limiting in poly（PBNAA） solution to the laser with 1064nm wavelength and 40ps pulses width mainly originates from the two-photon absorption of poly（PBNAA） molecules.