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Title: Impact of drops of epoxy resin and hardener, silicone and turpentine oils onto balsa wood and polypropylene substrates
Electrowetting and wettability-driven spreading of liquids on porous and nonporous substrates was investigated using impact of drops of epoxy resin, epoxy hardener, and epoxy resin and hardener, as well as silicone and turpentine oils with oil-soluble aniline dyes onto balsa wood and polypropylene surfaces. The experimental results revealed that the electric field stretched drops of epoxy resin, epoxy hardener, and epoxy resin and hardener after impact on polypropylene substrate in the long-term. The spreading of drops of epoxy resin and turpentine oil with dyes after impact onto porous balsa wood under the action of a 10 kV applied voltage was relatively weak. In addition, the measured footprint areas corresponding to drops of epoxy resin, epoxy hardener, and epoxy resin and hardener demonstrated a significant increase in the wetted areas driven by the applied voltage of 10 kV on polypropylene substrate, whereas on balsa wood, the footprint is practically unaffected by the electric field. Furthermore, it was determined that surface wettability was the main mechanism of spreading of epoxy resin, as well as silicone and turpentine oils with aniline dyes on porous balsa without the electric field applied. On the other hand, insufficient concentration of ions and counterions in silicone oil was responsible for the absence of electrohydrodynamic effects after impact of such drops onto porous balsa substrate subjected to high potentials of 7 and 10 kV. Hence, wettability-driven spreading with imbibition on balsa wood was the only reason for an increase in the wetted area in the case of silicone oil.  more » « less
Award ID(s):
2312197
PAR ID:
10520512
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Physics of Fluids
Volume:
36
Issue:
5
ISSN:
1070-6631
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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