Photoguided Shape Deformation of Azobenzene-Containing Polymer Microparticles.

Here we present the generation of uniform microparticles with tunable diameters from azobenzene-based homopolymer by combining the microfluidics technique and emulsion-solvent evaporation route. In addition, the photoinduced deformation behavior of these microspheres, irradiated by a linearly polarized beam with different irradiation time and direction, are systemically studied. The deformation process through real time optical microscope observation can be investigated, benefiting from the uniform and microscaled size of the polymer particles. These results indicate that the deformation degree characterized by relative variation of the long axial for the particles can be controlled by the irradiation time. Moreover, elongated particles with tunable aspect ratio or tilted shape can be generated by manipulating the irradiation direction and/or time. Interestingly, the shape transformation kinetics displays a significant dependence on initial size of the polymer particle. In addition, the shape transformation of the polymer particle can lead to the variation of the orientation and distribution of the encapsulated anisotropic gold nanorods.