Bin Jonghoon, Oates William S
Florida Center for Advanced Aero Propulsion (FCAAP), Department of Mechanical Engineering, Florida State University. Tallahassee, FL, 32310, USA.
Sci Rep. 2015 Oct 6;5:14654. doi: 10.1038/srep14654.
Complex light-matter interactions in azobenzene polymers have limited our understanding of how photoisomerization induces deformation as a function of the underlying polymer network and form of the light excitation. A unified modeling framework is formulated to advance the understanding of surface deformation and bulk deformation of polymer films that are controlled by linear or circularly polarized light or vortex beams. It is shown that dipole forces strongly respond to polarized light in contrast to higher order quadrupole forces that are often used to describe surface relief grating deformation through a field gradient constitutive law. The modeling results and comparisons with a broad range of photomechanical data in the literature suggest that the molecular structure of the azobenzene monomers dramatically influences the photostrictive behavior. The results provide important insight for designing azobenzene monomers within a polymer network to achieve enhanced photo-responsive deformation.
偶氮苯聚合物中复杂的光与物质相互作用限制了我们对于光异构化如何根据基础聚合物网络和光激发形式诱导变形的理解。我们制定了一个统一的建模框架，以促进对由线性或圆偏振光或涡旋光束控制的聚合物薄膜表面变形和体变形的理解。结果表明，与通常通过场梯度本构定律描述表面起伏光栅变形的高阶四极子力相比，偶极力对偏振光有强烈响应。建模结果以及与文献中广泛的光机械数据的比较表明，偶氮苯单体的分子结构对光致伸缩行为有显著影响。这些结果为在聚合物网络中设计偶氮苯单体以实现增强的光响应变形提供了重要见解。
