Phenylenevinylene Block Copolymers via Ring-Opening Metathesis Polymerization

Fully conjugated block copolymers containing 1,4- and 1,3-phenylenevinylene repeating units can be prepared by the sequential ring opening metathesis polymerization of strained cyclophanedienes, initiated by ruthenium carbene complexes (Grubbs metathesis catalysts). The molecular weight of the constituent blocks can be tightly controlled by changing the catalyst to monomer ratio and the volume fraction of the block copolymers independently tailored by the ratio of the monomers employed. Extensive phase separation between the constituent blocks is observed in thin films of these polymers by atomic force microscopy and efficient energy transfer between blocks containing 1,4- and 1,3-phenylenevinylene units can be seen in the photoluminescence of these materials.