Bending Materials with Light: Photoreversible Macroscopic Deformations in a Disordered Polymer

Abstract

An amorphous co‐polymer formed from norbornene and a photochromic ruthenium sulfoxide complex shows reversible macroscopic deformations when irradiated. Charge‐transfer excitation of the sulfur‐bonded isomer leads to isomerization and a macroscopic bending of the film. Charge‐transfer excitation of the oxygen‐bonded isomer reverses the bending. The macroscopic bending is ascribed to the molecular isomerization.

Switchable molecule-based materials for micro- and nanoscale actuating applications: Achievements and prospects

“…For example, Jin et al [16,71] reported a dilute, photochromic ruthenium sulfoxide-based polymer composite that efficiently deforms at room temperature under laser irradiation. The active material has a rather low concentration within the polymeric structure (2-4%) and a high level of cross-linking is present to ensure efficient propagation of the desired photomechanical effect.…”

“…Encircled numbers represent compounds. (1) Ruthenium sulfoxide-polymer composite[16], (2) diarylethene single crystal[17],(3)Fe(pyrazine)[Pt(CN)4] single crystal…”

Thermally and Optically Fixable Shape Memory in Azobenzene-Functionalized Glassy Liquid Crystalline Polymer Networks

“…The mechanical adaptivity of LCNs has garnered considerable recent attention for potential relevance in microfluidics [18], optics [19,20], structural mechanics [17,21,22], and medicine [23,24]. One of the salient features of LCN materials versus other stimuliresponsive polymers [25][26][27][28][29][30] is the ability to easily control the local director [2,[31][32][33][34] or defect [35][36][37][38][39] pattern within the film. The ability to manipulate the local anisotropy has been recently shown to be a highly distinctive method to engineer the shape and topography of LCN materials.…”

Photoinduced Bending Behaviour of Cross-linked Liquid Crystalline Polymers with High Cross-linking Densities

“…Much attention has been paid to photo-deformable materials owing to their ability to directly convert light into mechanical energy. [2,3] This photomechanical effect was exploited by incorporating a photoresponsive chromophore into organic crystals, [4] amorphous polymers, [5] and liquid crystalline (LC) polymers. [2a,6,7] Azobenzenes, which undergo reversible photoisomerization by absorbing energy from light, [7,8] have been widely used in this regard.…”