Parlon
From PyroGuide
Formula: (C4H6Cl2)n
Synonyms: Chlorinated rubber, chlorub, pergut
Description: Parlon is a acetone-soluble polymer that is used as a chlorine donor and binder. It is a good example of one of the new chemicals that has become available in the past few decades for use in compositions.
Hazards: Parlon is not particularly dangerous.
Sources: Parlon seems to be available from dedicated pyro suppliers only.