Perfluoroisobutylene (PFIB) is a schedule 2A substance under
the Chemical Weapons Convention, which means that while it
has significant ability to be used as a chemical weapon, it also
serves various other industrial uses.
Perfluoroisobutylene or perfluoroisobutene is a monomer used
in synthesis of Teflon and other polymeric materials. It is also
used in etching for semiconductor fabrication, and is potentially
used as a chemical warfare agent. The US Food and Drug
Administration’s CFR 21 Section 173.360 allows for use of
octafluorocyclobutane as a propellant and also allows for PFIB
at a level of <.01% as an impurity in formulation.
A deadly poison by inhalation. Askin, eye, and mucous membrane irritant. Human acuteexposure causes marked irritation of conjunctivae, throat,and lungs. When heated to decompos
PFIB exists as a gas in the atmosphere, and is degraded by
reaction with hydroxyl radicals, with a reaction half-life
of ~5.7 days. PFIB is not susceptible to significant photolysis.
The Henry’s law constant of PFIB suggests volatization as
an important fate process. The half lives for volatization
calculated from a model lake and river were 5.6 days and
4.1 h, respectively, though a small portion will adsorb to
suspended solids and sediment. PFIB can also volatize
substantially from moist soils, and to a small degree from dry
soils.
PFIB is a strong electrophile that reacts with nucleophiles. The
toxicity of PFIB may be correlated with its susceptibility to
nucleophilic attack and the generation of reactive
intermediates.
