A lineup of highly efficient ruthenium catalysts with N-containing substituents in the benzylidene ligand is developed that differ in the rate of initiation of dicyclopentadiene metathesis polymerization. The choice of the optimal catalyst makes it possible to control the lifetime of the monomer–catalyst reaction mixture in a wide range, which makes the use of various technologies effective for the production of polymer and composite materials. The new catalysts have been used to design a series of innovative polymer and polymer-composite materials with a polymer matrix based on a finished monomer, dicyclopentadiene, which is a raw material of the petrochemical industry. The polymeric materials are distinguished by a unique combination of high mechanical properties and good thermal stability in a wide temperature range (from –60 to +320°C), which allows their use in various climatic zones. Composites with a matrix based on polydicyclopentadiene are not inferior to commercially available counterparts based on epoxy and polyester resins and even surpass them in a number of parameters.