LSZH insulation isn't a single construction. Several low-smoke cabling alternatives can be used as an LSZH material, with the most popular being the cost-effective XLPE (Crosslinked Polyethylene). It's important to point out the major difference between PE and XLPE, as it's the crosslinking that provides additional flame resistance and smoke prevention.
Crosslinking is the formation of covalent bonds, which holds portions of multiple polymer chains together. Extensive cross-linking produces a substance with increased rigidness, hardness, and a higher melting point than the prior non-crosslinked version. Typically all hard and rigid plastic that we use today are crosslinked polymers.
