Epotuf 91-139 Bisphenol F based epoxy novolac resin Reichhold Epoxide (EP) >> Phenol & Cresol (Novolacs) ADHESIVE Epotuf 91-139 EPOTUF® 91-139 is a multifunctional Bisphenol-F based epoxy novolac resin. Lower viscosity than standard epoxy novolacs Higher functionality and crosslink density than Bis-A based epoxy resins Excellent chemical resistance Multifunctional bisphenol-F based epoxy novolac resin. Used in industrial adhesives. Provides lower viscosity than standard epoxy novolacs, higher functionality and crosslink density than bisphenol-A based epoxy resins and very good chemical resistance.