Abstract
Light-responsive devices are becoming increasingly relevant in many applications ranging from soft-robotics, energy harvesting, regenerative medicine and tissue engineering. Here we present a two-photon fabrication process based on a photocurable azopolymeric compound that we successfully employed to manufacture suspended micro-membranes. Thanks to the incorporation of azobenzene units, the membranes are shown to exhibit a remarkable mechanical photo-responsivity despite the disordered, amorphous structure of the crosslinked network. When irradiated with a focused laser beam at 532 nm wavelength, a reversible shape modification is observed, with a linear expansion coefficient as large as 28%. This effect is accompanied by a refractive index decrease of about 0.16, as measured interferometrically. The initial state of the membrane is fully recovered when the irradiation is switched off, as the cyclic photoisomerization process is stopped. The presented approach can be extended to light-induce complex modifications of the mechanical features in 3D printed objects by remotely providing arbitrary illumination patterns.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 10428-10434 |
| Number of pages | 7 |
| Journal | Journal of Materials Chemistry C |
| Volume | 6 |
| Issue number | 39 |
| DOIs | |
| State | Published - 2018 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): BAS/1/1064-01-01
Acknowledgements: This research has received funding from the Italian Flagship Project NANOMAX (Progetto Bandiera MIUR PNR 2011–2013) and from King Abdullah University of Science and Technology (KAUST) (BAS/1/1064-01-01). Dr Angelo Angelini is acknowledged for assistance at the interferometric imaging system. Mr Mauro Raimondo is acknowledged for technical assistance in electron microscopy imaging.