Nanoporous materials with spherical and gyroid cavities created by quantitative etching of polydimethylsiloxane in polystyrene-polydimethylsiloxane block copolymers.
A new method for quantitative etching of the poly(dimethylsiloxane) block in polystyrene-poly(dimethylsiloxane) (PS-PDMS) block copolymers is reported. Reacting the block copolymer with anhydrous hydrogen fluoride renders a nanoporous material (NPM) with the remaining glassy PS maintaining the original bulk morphology. 1H NMR, mass difference, size exclusion chromatography, and X-ray photoelectron spectroscopy were used to characterize the materials before and after etching. NPMs containing spherical and gyroid cavities were prepared, as ascertained by small-angle X-ray scattering. This is the first report on block copolymer-based NPM films of millimeter thickness containing secluded spherical holes. Surface images by AFM and SEM are consistent with the SAXS findings.
The Danish Polymer Centre, Risø National Laboratory, bldg. 111-124, DK-4000, Roskilde, Denmark. sokol.ndoni@risoe.dk
Sokol
S
Ndoni
Martin E
ME
Vigild
Rolf H
RH
Berg