In chemistry, vinyl or ethenyl (abbreviated as Vi) is the functional group with the formula H-C=CH2. It is the ethylene (IUPAC ethene) molecule (H2C=CH2) with one fewer hydrogen atom. The name is also used for any compound containing that group, namely R−CH=CH2 where R is any other group of atoms.
Vinyl is one of the alkenyl functional groups. On a carbon skeleton, sp2-hybridized carbons or positions are often called vinylic. Allyls, acrylates and styrenics contain vinyl groups. (A styrenic crosslinker with two vinyl groups is called divinyl benzene.)
Vinyl groups can polymerize with the aid of a radical initiator or a catalyst, forming vinyl polymers. Vinyl polymers contain no vinyl groups. Instead they are saturated. The following table gives some examples of vinyl polymers.
|Monomer example||Example of resulting polymer|
|Vinyl chloride||Polyvinyl chloride (PVC)|
|Vinyl fluoride||Polyvinyl fluoride (PVF)|
|Vinyl acetate||Polyvinyl acetate (PVAc)|
The etymology of vinyl is the Latin vinum = "wine", and the Greek word "hylos" 'υλος (matter or material), because of its relationship with ethyl alcohol. The term "vinyl" was coined by the German chemist Hermann Kolbe in 1851.