六羰基钨催化制备聚苯乙炔及其荧光性能的研究

用W(CO) 6 催化体系聚合苯乙炔 ,以高产率获得较高相对分子质量的聚苯乙炔。使用UV、IR、GPC等分别对聚苯乙炔结构进行表征。采用不同波长的激发光对聚苯乙炔荧光性能进行了详细研究 ,结果表明 :当聚苯乙炔用 31 0nm激光激发时 ,呈现 3个荧光发光峰 ,峰值分别在348、396和 61 0nm处 ,与其溶液的紫外吸收有类似的光谱曲线特征。荧光峰在 348nm处的荧光 ,当聚苯乙炔质量浓度大于 0 0 5g L时 ,呈现荧光猝灭效应 ;在聚苯乙炔质量浓度为 1 0 - 4g L时 ,呈现出最大的荧光发光量子效率。当激发光波长低于 2 70nm和高于 340nm时 ,348nm波长荧光消失 ;荧光峰在 396nm处的荧光 ,当聚苯乙炔的质量浓度为 1 0 - 2 g L时 ,呈现最大的发光量子效率 ,聚苯乙炔的质量浓度增大或降低 ,其发光强度均呈现减弱现象 ;荧光峰在 61 0nm的荧光 ,在聚苯乙炔质量浓度为 1 0 - 4g L时 ,呈现最大的发光量子效率。荧光性能研究结果证明这种催化剂获得的聚苯乙炔具有多种异构链结构。

Fluorescence Properties and Syntheses of Polyphenylacetylenes Catalyzed by W(CO)6

Polyphenylacetylenes were synthesized using the catalyst system W(CO)\-6 in different solvents.The polymers with high weight average molecular weight were obtained in high yield.Their structures were characterized by UV,IR,and GPC.The fluorescences of the polymers were investigated using variable excitation wavelength from UV to visible region.At the excitation wavelength of 310 nm,the polymer solution in THF showed the fluorescence emission peaks at 348,396 and 610 nm.For the fluorescence emitted at 348 nm,the hightest yield was obtained in the polymer solution of 10 -4 g/L and the fluorescence exhibited concentration quenching effect when the concentration of polymer was higher than 0 05 g/L.The fluorescence emitted at 348 nm vanished was observed when the excitation wavelength was lower than 270nm or higher than 340 nm.For the fluorescence emitted at 396nm,the highest yield was obtained in the polymer solution of 10 -2 g/L and at 310-nm excitation wavelength.For the fluorescence emitted at 610 nm, the highest yield was obtained in the polymer solution of 10 -4 g/L and at excitatiom wavelength of 270 nm.The relations between structure and fluorescence properties were discussed.These results showed the uneven polymer structure.