Chlorendic acid

Chlorendic acid (CAS 115-28-6, EC 204-078-9), also known as HET acid, is a chlorinated cyclic dicarboxylic acid derived from hexachlorocyclopentadiene. With the molecular formula C9H4Cl6O4, it carries six chlorine atoms per molecule, giving it a high halogen content that underpins its functional properties in reactive polymer systems.

In flame-retardant polyester and alkyd resin formulations, chlorendic acid is incorporated as a reactive comonomer, chemically bonding into the polymer backbone rather than acting as an additive. This covalent integration reduces leaching and delivers durable fire resistance in electrical laminates, construction panels, and aerospace composite components.

Chlorendic acid is supplied as a solid and is subject to REACH registration requirements within the European Economic Area. Procurement teams should verify current SVHC status and request a full safety data sheet prior to ordering. Standard industrial packaging applies; consult our team for available lot sizes and documentation.