An all-polymer micropump based on the conductive polymer poly(3,4-ethylenedioxythiophene) and a polyurethane channel system

An all-polymer micropunlp was realized using the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDT) as the active cODlponent. The pUlnping effect originated fronl an ac potential applied to an aSylnlnetric array of interdigitat.ed electrodes. The PEDT electrodes were fabricated using optical lithography and reactive ion etching, and dimensions down to 2 jtD) could be successfully realize·d.

The channel systeDl wasm.ade froln a flexible thennoplastic polyurethane. The chosen polyurethane exhibited good sealing without the possible contanlination issues of silicones, adequate wetting without plasma treatment, and has the potential for Dlass production, e.g., by injection lTIoulding. The assembled micropunlp showed a pUDlping speed of 150 /LID s-l at a frequency of 10 kHz and an alnplitude of 5 V.

Higher potentials resulted in pennanent dalnage to the pUlnp electrodes. Encapsulation of t.he conducting polylner electrodes by an insulating polYlTIer layer prevented electrode break-down at the cost of puolping efficiency. Continuous punlping for 40 nlin at 20 fJ..,m s-l without detectable pump degradation was delTIOnstrated in this configuration.