偶氮聚合物三角状聚集体的制备及光致形变行为研究

FABRICATION OF BOWL-SHAPED AGGREGATES OF AZO POLYMER AND THEIR PHOTOINDUCED DEFORMATOIN BEHAVIOR

利用滴加沉淀剂法,通过偶氮聚合物BP-AZ-2CA在DMF-H2O体系中自组装得到了碗状的聚集体.利用透射电镜等对聚集体的组装过程及最终形貌等进行了表征.研究表明,通过调节初始聚合物浓度以及制备过程中的滴加水速率,可得到不同尺寸的碗状聚集体.将碗状聚集体置于单束偏振Ar+激光(488nm,110mW/cm2)照射下,所有的碗状聚集体都发生了沿着激光偏振方向的拉伸.碗状聚集体在激光拉伸后仍然维持中空的结构.

The bowl-shaped aggregates were prepared by using an azo polymer （ BP-AZ-2CA）,and their photoinduced deformation behavior was studied. The bowl-shaped aggregates were prepared through gradual hydrophobic aggregation of the polymeric chains in DMF-H2O media and characterized by using TEM. critical water content （CWC） was obtained by the light scattering measurement. The results showed that two types of aggregates formed in the system,one was small colloidal spheres and the other was bowl-shaped aggregates. The aggregates with different average diameters were obtained by adjusting the initial polymer concentration and water-adding rate in the preparation processes. The photoinduced deformation behavior was studied by irradiating the bowl-shaped aggregates in solid state with a linearly polarized Ar ＋ laser beam （488 nm,110 mW /cm2） for different time periods. Upon the light irradiation,the bowl-shaped aggregates were elongated along the polarization direction of the laser beam especially when the irradiation time was longer than 15 min. The hollow space in the aggregates almost remained unchanged after irradiation. The morphology of the bowl- shaped aggregates after irradiation changed with the angle between the bowl-shaped aggregates and the polarization direction of the light beam.