Core-Cell is styreneacrylonitrile. More detail at
http://www.atc-chem.com/Core_Cell/Core_cell.asp
I wouldn't be surprised if its sales volume has surpassed Airex and Klegecell.
It's very nice stuff to work with.

GIDE wrote:

Klegecell is a PVC foam , Core-cell is a polyurethane foam , it is not the
same , Airex is the polyurethane foam mostly used in boatbuilding . There
many kind of foam and they have different specification , it is really not
like rhum.

SNIP