Why Are Some E-liquids Thicker?

This type of phenomenon is usually most noticeable in e-Liquid blends that use 100%VG (vegetable glycerin) as the base liquid. The confusion comes from the fact that an “all VG base” is not necessarily the same as an “all VG eLiquid”.

The thickness or thinness of a liquid blend (i.e., “viscosity” in geek-speak) depends on the chemical components in the blend, their relative amounts, and their compatibilities (think of oil and water). We pre-dissolve some flavoring components to make them more compatible with VG. These flavor solutions can then be easily mixed (in very small amounts) with VG and appropriate amount of liquid nicotine to produce a desired eLiquid blend.

Since these solvents have very different viscosities, the relative amounts of VG, PG, and/or ethanol determine the thickness of the final blend.  Viscosities are typically measured in centipoise - abbreviated cP in honor of the scientist Jean Léonard Marie Poiseuille.  While ethanol (and water) have a viscosity of about 1 cP at normal room temperatures, PG is somewhat thicker at 45-50 cP, and VG clocks in at 1200-1400 cP.

With all that being said, some flavorings we use are very intense and concentrated, and take only a little to achieve a desired taste. Other flavors are more subtle, needing a stronger dose to get the desired taste. What this can cause is for some liquids to have different consistencies in thickness.

Our Blue Label eLiquid blends are essentially 100% VG as defined by its base liquid. There are no 100% VG eLiquids; as the contents of the bottle would only be VG. When you add nicotine and flavoring the VG becomes less than 100% (as liquid total… not as base liquid total) by definition. Adding other ingredients changes each eLiquids viscosity (thickness) as all ingredient types are different and react different with other ingredients. 

Written by:

Ph.D. chemist Dr. Tony Pace.

• BS Chemistry - University of Florida
• PhD Chemistry - University of Texas, Austin
• Robert A Welch Foundation Research Fellowships
• Adjunct Professor of Chemistry - Emory University, Atlanta
• Visiting Research Fellow - Georgia Institute of Technology, Chemistry Dept.
• 25 years experience in Industrial R&D with Fortune 500 companies
• Holds 3 US Patents
• Has 7 Journal Publications