1,1-Difluoroethylene

1,1-Difluoroethylene, also known as vinylidene fluoride, is a hydrofluoroolefin. This colorless, flammable gas is a difluorinated derivative of ethylene. Global production in 1999 was approximately 33,000 metric tons. It is primarily used in the production of fluoropolymers such as polyvinylidene fluoride and FKM.

Preparation
1,1-Difluoroethylene can be prepared by elimination reaction from a 1,1,1-trihaloethane compound, for example, loss of hydrogen chloride from 1-chloro-1,1-difluoroethane:


 * Preparation of 1,1-difluoroethylene from 1-chloro-1,1-difluoroethane.png

or loss of hydrogen fluoride from 1,1,1-trifluoroethane:


 * Preparation of 1,1-difluoroethylene from 1,1,1-trifluoroethane.png