Fast and self-recoverable photoinduced deformation behavior of azobenzene-containing poly(arylene ether)s with binaphthalene groups

The research on the photomechanical effects of azobenzene-containing high performance polymer materials has received much attention due to their potential applications in high temperature environments. At present, there are few types of photoinduced deformable polymers based on azobenzene-containing high performance polymers, and their photoinduced deformation rates need to be improved. In this paper, a novel series of azobenzene-containing poly(arylene ether)s with various contents of binaphthalene groups were synthesized. Introducing binaphthalene groups into azobenzene-containing poly(arylene ether)s was a helpful strategy to increase the free volume, which could increase the photoinduced deformation rates of the polymers. Under 442 nm unpolarized laser irradiation, the photoinduced deformation rates increased with the contents of binaphthalene groups of the polymers. Under 442 nm polarized laser irradiation, the cantilevers of the azobenzene-containing poly(arylene ether)s have shown unusual photoinduced deformation behavior. When the polarization direction of the polarized laser was perpendicular to the long axis of the cantilevers of the polymers, the cantilevers bent away from the excitation laser at the beginning, then bent towards the excitation laser and could reach the initial position. The angles of the polymers bent away from the excitation laser increased with the contents of binaphthalene groups of the polymers. The photoinduced deformation behavior of the polymers could be adjusted by adjusting the polarization direction of the polarized laser, the laser power and the thickness of the cantilevers of the polymer. This interesting phenomenon has not been reported in previous research on the photoinduced deformation behavior of azobenzene-containing high performance polymers.