Richard Vance's credentials suggest that he might be a person who could
tell us why Perflex -- that infamous pouch panacea of the '70s turned
plague of the '80s -- disintegrated spontaneously after a few years.
I've heard various theories, including the popular notion that the heat
deformation to form the pouches initiates the self-destructive process,
and also that mechanical stresses resulting from valve operation are to
blame.

These may contribute to the problem, but there's more to it.  I had some
Perflex sheeting in bulk form that fell apart after being stored in a
friendly environment for several years.  I also had a set of pre-formed
Perflex pouches from Player Piano Co. that disintegrated spontaneously in
the container.  Those were presumably pre-formed by heat, but were never
put into service.

An intriguing question is whether a material with similar properties
might eventually be re-compounded to extend its life expectancy to
something on the order of several decades or more?  My knowledge of
chemistry is somewhere between scanty and nil, but it seems to me that if
the failure mechanism were known, there might be some way to circumvent
it.  Even if that could be successfully done, of course, gaining the
confidence of the restoration community might somewhat difficult at this
point in time.

Dave Saul