Synthetic oil

Synthetic oil is a lubricant consisting of chemical compounds that are artificially made. Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be synthesized from other raw materials.

Synthetic oil is used as a substitute for petroleum-refined oils when operating in extreme temperature.. Aircraft jet engines, for example, require the use of synthetic oils, whereas aircraft piston engines do not. Synthetic oils are also used in metal stamping to provide environmental and other benefits when compared to conventional petroleum and animal-fat based products. These products are also referred to as "non-oil" or "oil free".

Full synthetic oils are derived from crude oil or byproducts through a chemical process rather than the distillation process used for conventional oil. The resulting synthetic oil has a more consistent molecular size and therefore tends to have somewhat more uniform properties. The [base oil] s are categorized by American Petroleum Institute into API Groups III, IV & V.

Poly-alpha-olefin (or poly-α-olefin, abbreviated as PAO) is a polymer made by polymerizing an alpha-olefin. They are designated at API Group IV and are a 100% synthetic chemical compound. It is a specific type of olefin (organic) that is used as a base stock in the production of some synthetic lubricants. An alpha-olefin (or α-olefin) is an alkene where the carbon-carbon double bond starts at the α-carbon atom, i.e. the double bond is between the #1 and #2 carbons in the molecule.

Group V base oils are defined by API as any other type of oil other than mineral oils or PAO lubricants.

Esters are the most famous synthetics in Group V, which are 100% Synthetic chemical compounds consisting of a carbonyl adjacent to an ether linkage. They are derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH (hydroxyl) group is replaced by an -O-alkyl (alkoxy) group, most commonly from carboxylic acids and alcohols. That is to say, esters are formed by condensing an acid with an alcohol.

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