Abstracts Book - IMRC 2018

• SB1-O036
MULTILEVEL TOPOGRAPHICAL CHANGES OF POLYMERIC
SURFACES CONTROL THEIR AEROPHOBIC BEHAVIOR
Yi Jiang 1 , Mansfeld Ulrich 1 , Karl Kratz 1 , Andreas Lendlein 1
1 Helmholtz Zentrum Geesthacht, Institute of Biomaterial Science, Germany.
Tailoring of polymeric materials with regard to surface functions is a major
challenge within the development of advanced materials. In particular, surfaces
showing controlled wettability of gas bubbles are of great interest in many fields
such as electrode design and medical devices. Alteration of the aerophobicity of
polymeric surfaces is often associated to changes in the materials´ chemical
nature. Here we present non-swellable polymeric surfaces responding to heat
with multilevel topographical shape changes causing a drastic change in their
aerophobic behavior. The functional surfaces were prepared by structuring of
well-defined micro- and nanostructured polymeric materials based on a crosslinked
poly[ethylene-co-(vinyl acetate)] and subsequent thermomechanical
treatment. The smart surfaces were able to restore their topographical microand
nanostructures with high precision upon heating, whereby the switching
temperature could be adjusted in the range 41±1 °C to 79±1 °C by solely
physical manipulation. Simultaneous topographic changes on nano- and
microscale were achieved as monitored by in-situ AFM investigations. The
material’s hydrophobicity allows to conduct wettability investigations via the
captive bubble method in an aqueous environment. Upon heating, a significant
change in contact angle aerophilic to aerophobic behavior was observed and in
this way the initial adhesion of air bubbles could be turned into repellence. The
temperature where the repellence of air bubbles starts can be adjusted 58±1 °C
to 73±1 °C by varying the thermomechanical treatment. The presented soft
surfaces are attractive candidates for biotechnological applications, where a
temperature-controlled on demand gas bubble repellence is advantageous.
Acknowledgment:
The work was supported by the German Federal Ministry for Education and
Research and the Helmholtz association of program-oriented funding.
Keywords: aerophobicity, polymer surface, tunable switching temperature
Presenting authors email: ulrich.mansfeld@hzg.de