What are the key product streams from pyrolysis C5 and their main industrial applications?

What are the key product streams from pyrolysis C5 and their main industrial applications?
Pyrolysis C5, a by-product of steam cracking naphtha for ethylene, accounts for roughly 10% of ethylene output. It contains over 30 close-boiling components, with the most valuable being isoprene, piperylene, and cyclopentadiene, together comprising 40-55% of the fraction, plus 15-25% mono-olefins like 1-pentene and methylbutenes. Isoprene is the key monomer for polyisoprene rubber, SIS block copolymers, and butyl rubber, and also feeds synthesis of vitamin E, fragrances, and pyrethroid pesticides. Piperylene is mainly used for C5 petroleum resins and methyl hexahydrophthalic anhydride curing agents for epoxy resins, which are critical in electronics and outdoor LED applications. Cyclopentadiene derivatives include DCPD resins and specialty materials. The complexity of separation and the need for high-purity streams make this fraction both technically challenging and commercially attractive for integrated producers.