Studies of the metathesis polymerization and copolymerization of syn‐ and anti‐7‐methylnorbornene initiated by the tungsten‐carbene complex

The tungsten‐carbene complex was used to initiate the metathesis polymerization of syn‐and anti‐7‐methylbicyclo [2.2.1] hept‐2‐ene (Ms and Ma). Two kinds of experiment were performed:(i) the reactions were followed at low monomer/initiator ratios by 1H NMR spectroscopy at 220–250K; (ii) polymers and copolymers of Ms and Ma were prepared at room temperature and their microstructure analysed by 13C NMR spectroscopy. The propagating tungsten‐carbene species derived from both Ma could be detected. Some rate constants were evaluated for various steps in the mechanism. A polymer of Ms was prepared for the first time, containing 90% trans double bonds and probably isotactic. After hydrogenation this polymer exhibits two first‐order transitions, with DSC maxima at 179 and 230°C. Hydrogenated atactic polymers of Ma and of norbornene also exhibit first‐order transitions. Conditions are described for the preparation of block and tapered block copolymers of Ma and Ms.