%0 Journal Article %A Duell, Anna K. %A Pankow, James F. %A Gillette, Samantha M. %A Peyton, David H. %D 2018 %T Boiling points of the propylene glycol + glycerol system at 1 atmosphere pressure: 188.6–292 °C without and with added water or nicotine %U https://tandf.figshare.com/articles/journal_contribution/Boiling_points_of_the_propylene_glycol_glycerol_system_at_1_atmosphere_pressure_188_6_292_C_without_and_with_added_water_or_nicotine/6387782 %R 10.6084/m9.figshare.6387782.v1 %2 https://tandf.figshare.com/ndownloader/files/11756684 %K E-Cigarette liquid %K Electronic cigarette %K Electronic nicotine delivery system (ENDS) %K Glycerol %K Heat exchanger fluid %K Propylene glycol %X

In electronic cigarettes (“electronic nicotine delivery systems”, ENDS), mixtures of propylene glycol (PG) and/or glycerol (GL; aka “vegetable glycerin”, VG) with nicotine are vaporized to create a nicotine-containing aerosol. For a given composition, the temperature required to boil the liquid at 1 atmosphere must be at least somewhat greater than the boiling point (BP). The use of ENDS is increasing rapidly worldwide, yet the BP characteristics of the PG + GL system have been characterized as the mixtures; here we re-do this, but significantly, also study the effects of added water and nicotine. BP values at 1 atmosphere pressure were measured over the full binary composition range. Fits based on the Gibbs–Konovalov theorem provide BP as a function of composition (by mole-percent, by weight-percent, and by volume-percent). BPs of PG + GL mixtures were then tested in the presence of additives such as water (2.5 and 5 mol% added) and nicotine (3 mol%). Water was found to decrease the BP of PG + GL mixtures significantly at all compositions tested, and nicotine was found to decrease the BP of PG + GL mixtures containing ∼75 GL: 25 PG (by moles) or more. The effect of added water (5, 10, and 15 mol% added) on electronic cigarette degradation production (some aldehydes and formaldehyde hemiacetals) was examined and found to have no significant impact on solvent (PG or GL) degradation for the particular device used.

%I Taylor & Francis