A compound is prepared, suitable for forming fluoroelastomers, having the
unique features of a low glass transition temperature and desirable
permeation resistance. The compound generally comprises two primary
components. The first component is an amorphous copolymer including
interpolymerized units derived from one or more perfluorinated ethers.
The second component is a curable component including at least one filler
having at least 10 parts per 100 parts of the first component. Upon
vulcanization the resulting elastomeric compound has desirable physical
characteristics as indicated by the durometer, the retraction at lower
temperatures (TR-10) and permeation resistance.