Chloroprene, 2-chloro-1,3-butadiene, is a colorless, volatile
synthetic liquid that has a pungent ether-like odor. Synthesis
of chloroprene was first reported by chemists of the E. I. du
Pont de Nemours Company in 1931 following studies of
acetylene polymerization with the objective of producing
synthetic rubber. The chloroprene monomer differs from
isoprene, the fundamental monomer of natural rubber, only
by substitution of chlorine for the methyl group of isoprene.
Chloroprene was observed to polymerize much more
quickly than did isoprene. In industrial processes prior to
1960, chloroprene was produced in relatively high yields by
reacting vinyl acetylene with hydrogen chloride. Today,
chloroprene is produced more efficiently by chlorination of
1,3-butadiene.
When compared with natural rubber the chloroprene
synthetic polymer, polychloroprene, was noted to be much
denser, more resistant to water and hydrocarbon solvents,
less permeable to many gases, and was more resistant
to degradation by oxygen, ozone, hydrogen chloride,
hydrogen fluoride, and other chemicals. Due to desirable
physical and chemical properties, polychloroprene and its
latex polymers are produced in quantities exceeding
200 000 metric tons at a limited number of facilities
around the world. Chloroprene production is closely tied to
demand for polychloroprene.
