| Abstract
| - We have examined charge stability limits of single evaporating microdroplets that were suspended inan electrodynamic balance. A high precision light scattering technique based on optical resonances wasused to determine the size and the size change of a droplet at a charge instability induced breakup. Thecharge level and the charge loss at the breakup were obtained from the dc voltages required to balancethe droplet prior to and following the breakup. The results on droplets of diethyl phthalate (DEP), diethyleneglycol (DEG), triethylene glycol (TEG), and hexadecane show that breakups due to the charge instabilityoccur at the Rayleigh charge limit. The observed charge losses during breakups range from about 15.3%for hexadecane droplets to about 41.1% for TEG droplets. Hexadecane droplets lose about 1.5% of theirmass, while DEP droplets, about 2.3%. Within the detectable limit of 0.03%, no mass losses were observedduring breakups of DEG and TEG droplets. The observation of extremely low mass losses that accompanyhigh charge losses from DEG and TEG droplets suggests that the process of breakups of DEG and TEGdroplets is distinct from that of DEP and hexadecane droplets. An analysis of the results indicates thatbreakups of DEP and hexadecane droplets result in the formation of a few large progeny droplets, whileTEG and DEG droplets produce thousands of fine progeny droplets.
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