Abstract: Moldable intumescent thermoplastic elastomer materials are disclosed based on suitable proportions of polyethylene, chlorinated polyethylene and a silicone elastomer with silphenylene siloxane monomer moieties and stabilizers, all with foamers, char formers and fillers. Examples of suitable silphenylene-siloxane monomer moieties are 1,4-phenylene-hexamethyltrisiloxanyl and 1,4-phenylene-1,1,3,5,5-pentamethyl-3-vinyltrisiloxanyl where the respective methyl groups may be replaced with suitable phenyl groups or other lower alkyl groups and their fluorinated analogs.