posted on 2023-12-06, 22:06authored byVolodymyr Tkachenko, Sara Coppola, Veronica Vespini, Daniele Tammaro, Pier Luca Maffettone, Pietro Ferraro, Simonetta Grilli
The electrohydrodynamic (EHD) jetting
of fluids is used for several
applications such as inkjet printing, atomization of analyte in mass
spectrometry, liquid metal alloy ion sources, and electrospinning
of polymer fibers. Historically, the bulk of research has focused
on nonviscous, highly conductive fluids which are most suitable for
EHD spray and printing, while there is relatively little experimental
work on EHD jetting of highly viscous liquid dielectrics. We studied
the dynamics of oscillation and pulsating jetting from a suspended
drop of polydimethylsiloxane (PDMS) polymers in an electric
field, with particular attention to the viscosity dependence of the
oscillation period and meniscus elongation and contraction time over
a wide viscosity range (102–105 cSt).
The reported results could help the appropriate design of EHD processes
and may open new possibilities for the rheological characterization
of liquid polymers using small volumes at the scale of nanoliters.