Abstract: A series of palladium compounds as described herein are found to be superior vinyl addition polymerization catalysts. Specifically the compounds of formulae (I) and (II) as described herein surprisingly exhibit much higher reactivity than the compounds known in the art in the vinyl addition polymerization of a variety of cyclo-olefinic monomers, and thus polymers of very high molecular weight can be formed. Also disclosed are the formation of a variety of solid three dimensional objects, such as for example, solution extrusion of the polymer solutions formed from the vinyl addition polymerization of a variety of cyclic-olefinic monomers utilizing very low levels of palladium compounds of formulae (I) or (II) as described herein. The polymer films formed from the polymerization composition exhibit hitherto unattainable properties, for example superior transparent properties, higher thermal and mechanical properties, among other improved properties.