重氮偶合方法合成主链型光响应偶氮聚合物

提出了一种利用重氮偶合方法合成主链偶氮聚合物的新方法,合成了一种主链含有假芪型偶氮生色团的聚合物.对合成聚合物的结构、热性能以及光响应性能进行了详细表征.在线偏振激光的作用下,聚合物膜中的偶氮苯生色团发生光致取向,用偏振紫外-可见光光谱测量了此聚合物膜的二向色性,得到聚合物膜的取向有序度为0.03.用波长为488 nm,能量密度为150 mW/cm2的相干Ar+激光对聚合物膜照射1000 s,得到形貌规整的正弦波形表面起伏光栅,光栅的周期为900 nm,起伏深度为89 nm.

SYNTHESIS OF A MAIN-CHAIN PHOTO-RESPONSIVE AZO POLYMER THROUGH AZO-COUPLING REACTION

A novel polymer PAPE,containing electron donator-acceptor azobenzene chromophores in the main chain,has been synthesized by azo-coupling reaction.The azo polymer was characterized by()~1H-NMR,UV-Vis spectrometry and thermal analysis.The λ_(max) of the polymer film and DMF solution was determined to be 445 nm and 446 nm,respectively.The number average molecular weight determined by GPC was M_n=5600 with a polydispersion index 2.2.The glass transition temperature(T_g) of the polymer was 132℃ observed from DSC thermogram.The results showed the azo polymer can be successfully synthesized through azo-coupling reaction.The synthetic scheme demonstrated in this work is a feasible way to prepare main-chain azo polymers under an extremely mild condition.Dichroism was optically induced in the PAPE films under the irradiation of Ar~+ laser beam at 488 nm,and the orientational order parameter obtained was 0.03.Surface-relief-gratings were observed on PAPE films after irradiated by an interference pattern of Ar~+ laser beam for 1000 s.The surface modulation depth and the grating spacing were measured by AMF to be 89 nm and 900 nm.