A composition is described comprising a ring opening metathesis polymerization catalyst or precatalyst thereof; and an unreactive dispersant having a viscosity at 25° C. of at least 10 Pa·sec at a shear rate of 1 1/sec. Also described is a cartridge (e.g. or a dispensing and mixing apparatus) comprising such composition. The cartridge typically comprises a first chamber comprising unpolymerized cyclic olefin; and a second chamber comprising the catalyst and dispersant. Also described are compositions including two-part compositions and methods of bonding a substrate.