Remote radiofrequency triggering of topography changes in a surface micropatterned PANI@PNIPAM nanocomposite

L. E. MULKO; E. A. CUELLO; C. A. BARBERO; G. A. PINO; M. MOLINA; M. ROSSA

APPLIED SURFACE SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2020 vol. 509 p. 1453701 - 1453707

0169-4332

The presence of polyaniline (PANI) conducting polymer loaded in thick films of a transparent and thermosensitivepoly(N-isopropylacrylamide) (PNIPAM) hydrogel network allowed for absorption of UV light andmodification of dry (PANI@PNIPAM) nanocomposites by direct laser interference patterning (DLIP) at 355 nm.This resulted in a surface morphology of a nano-foam superimposed on a dominant line/groove pattern. Theobservations are rationalized based on currently accepted mechanisms for laser-induced polymer surfacemodification. Furthermore, the PANI in the nanocomposite films absorbs radiofrequency (RF) radiation remotelyinducing the volume phase transition of PNIPAM. The swelled, low-roughness state for PANI@PNIPAM collapsedinto a non-swelled and patterned film. The procedure provided the optimum RF dose range for preserving the surface topography of the films. The evidence suggests that the DLIP processing of PANI@PNIPAM films preservethe thermosensitivity of the original PNIPAM material and shows up the potential for tuning the surface morphology of the composite due to synergistic effects of both RF actuation on PANI and temperature rise of PNIPAM. In this sense, the surface pore size increase accompanying the development of line/groove pattern by DLIP, creates a structure onto PANI@PNIPAM films with potential for the development of remotely triggered soft-sensors and drug delivery systems.