Cationic Polymerization Alkene is treated with an acid. Intermediate must be a stable carbocation. Initiation steps:The catalyst protonates the monomer,starting the chain. F H CH: B*+H,O:- CH; →H-C-C +FBOH CH, H isobutylene initiated chain Propagation step:Another molecule of monomer adds to the chain. H H CH,H CH CH CH CH,- CH CH CH H CH,H CH; growing chain isobutylene elongated chain polymer Chapter 26 => 7Chapter 26 7 Cationic Polymerization • Alkene is treated with an acid. • Intermediate must be a stable carbocation. =>