resols are used extensively for the crosslinking of EPDM in the production of TPVs.
The EPDM phase is generally crosslinked with reactive alkylphenolic resins (e.g., Schenectady SP 1045) and halogen containing compounds.
Metal halides from Bronsted acid complexes like hydrated stannous chloride, ferric chloride or zinc chloride have been proposed as catalysts for this crosslinking system.