A_2和B_3单体重氮偶合反应制备超支化偶氮聚合物

HYPERBRANCHED AZO POLYMERS SYNTHESIZED BY AZO-COUPLING REACTION OF A_2/B_3 MONOMERS

利用A2/B3单体通过重氮偶合反应制备了超支化偶氮聚合物.利用核磁共振、红外光谱、紫外光谱和DSC热分析手段表征了聚合物的结构、光谱性能和玻璃化转变温度.合成的超支化偶氮聚合物具有很好的光响应性能,用488nm Ar+激光对超支化偶氮聚合物薄膜进行光加工,得到了规则的表面起伏光栅.

An A2 ＋ B3 method of preparing hyperbranched azo polymers by azo-coupling reactions was described.The hyperbranched precursor with diazonium salt groups on the periphery was prepared by step-growth polymerization of A2 （diazonium salts of 4, 4＇-diamino diphenyl sulphone）/B3 （benzene-1, 3, 5-tricarboxylic acid tri-2-（ N- ethylanilino） ethyl ester）monomers through azo-coupling reaction. Benzene-1, 3, 5-tricarboxylic acid tri-2-（ N- ethylanilino） ethyl ester was prepared by Schotten-Baumann reactions between 1,3,5-benzenetricarbonyl chloride andN-ethyl-N-hydroxyethyl-aniline. Then the hyperbranched precursor with diazonium salt groups on the periphery was further reacted with N, N-diethyl aniline by azo-coupling reaction to obtain the final hyperbranched azo polymer. The azo polymer was characterized by the spectroscopic methods and thermal analysis. The phase transition behavior of the hyperbranched azo polymer was studied by using the differential scanning calorimetry （DSC）. The hyperbranched polymer showed a second-order phase transition of typical amorphous substances. The Tg of thehyperbranched azo polymer was about 161℃. As containing the donor-acceptor type azo chromophores, the polymer showed typical spectral characteristics of the pseudo-stilbene type azo chromophores. The λmax value of the hyperbranched azo polymer, corresponding to the π-π^＋ transition, was about 465 nm. Spin-coated thin films of the hyperbranched azo polymer were used to carry out the SGR inscription experiments. Two p-polarized Ar^＋ laserbeams （488 nm） with an intensity 80 mW/cm^2 were used to produce the interference pattern on the polymer film. After irradiated for 1000 s at room temperature, the surface modulation depth was about 100 nm, and the grating spacing was about 730 nm. The modulation depth depended on the irradiation energy, and the spatial period depended on both the angle between the two interfering beams and the wavelength of the writing beams. Complex patterns could be inscribed when two gratings were recorded orthogonally to each other at the same location.