Epoxide

An epoxide is a cyclic ether with a three-atom ring. This ring approximates an equilateral triangle, which makes it strained, and hence highly reactive, more so than other ethers. They are produced on a large scale for many applications. In general, low molecular weight epoxides are colourless and nonpolar, and often volatile.

Nomenclature

A compound containing the epoxide functional group can be called an epoxy, epoxide, oxirane, and ethoxyline. Simple epoxides are often referred to as oxides. Thus, the epoxide of ethylene (C₂H₄) is ethylene oxide (C₂H₄O). Many compounds have trivial names, ethylene oxide is called "oxirane." Some names emphasize the presence of the epoxide functional group, as in the compound 1,2-epoxycycloheptane, which can also be called 1,2-heptene oxide.

A polymer formed from epoxide precursors is called an epoxy, but such materials do not contain epoxide groups (or contain only a few residual epoxy group that remain unreacted in the formation of the resin).