Other applications bayhydur xp 2655 hydrophilic hdi polyisocyanate low viscosity and easy to disperse type hydrophilic aliphatic polyisocyanate based on hexamethylene diisocyanate (hdi), used as curing ... 11/15196Covestro Bayhydur XP 2655 Hydrophilic HDI polyisocyanate Low viscosity and easy to disperse