What is VG
What is VG? (Vegetable Glycerin)
VG, or Vegetable Glycerin, is the other component of e-liquid. This liquid will be sweet and also really thick. The result of the VG thickness will be more vapor when exhaling than PG. The negative about the thickness of the VG is the possibility of burning or clogging problems in some e-cig equipment if the concentration of the VG is high. Higher volumes should not be used with standard tanks. Because of the VG sweetness, the flavor will tend to dull or change a little bit and will also have throat hits reduced that someone experiences.
Where Does VG Come From?
The VG part of e-liquid is a polyol compound and is obtained from animal and plant sources when occurring as a triglyceride, which is an ester of glycerol that has carboxylic acids with long chains. The triglycerides will produce glycerol through transesterification, saponification, or hydrolysis. The usual sources that are plant based are palm or soybeans. Tallow, which is derived from animals, is another triglyceride source. Glycerol is also able to be produced using a variety of routes from propylene. This method is not usually cost effective. A process called epichlorohydrin is most vital. It will involve propylene chlorination that will produce allyl chloride. The allyl chloride will then be oxidized using hypochlorite to dichlorohydrins, which will then react with a sturdy base that gives epichlorohydrin that will be hydrolyzed, giving glycerol.
What are Other Uses of VG?
Like PG, VG also has other uses other than for e-liquid. In the food industry, VG is used as a sweetener, solvent, humectant, and could help preserve some foods. In low-fat foods, like cookies, it is used as a filler. In liqueurs, it is used as a thickening agent. Along with water, VG can help preserve particular plant leaves. It is also used for substituting sugar but is not as sweet as sucrose. However, VG does NOT feed bacteria that forms plaque that causes cavities on teeth. Frosting, or icing, has VG to keep it from setting too hard. In personal care products and medications, it is used to improve the smoothness that provides lubrication. Examples of this use are cough syrups, expectorants and elixirs, mouthwash, toothpaste, products for skin care and hair care, shaving cream, personal lubricants that are water-based, and soaps.
As a chemical intermediate, glycerol is used for producing nitroglycerin, an essential ingredient for a variety of explosives like gelignite, dynamite, and cordite. The reliance on making soap to supply glycerol was hard to have the production increased during wartime to meet demand. Therefore, processes for producing synthetic glycerol became a national defense priority during the time that led to WWII. There is a lot of research being done for making products that are value-added from crude glycerol that is obtained from producing biodiesel. Also being explored is using crude glycerol as a biomass additive for renewable energy. As a couple of fun facts, Vegetable Glycerol is used for powering diesel generators that supply electricity for FIA Formula E race cars and in the filming industry, it is used by filmmakers that involve water scenes to prevent the areas being filmed from drying out too fast.