New functional monomers for well-controlled ROMP polymerizations

The ring-opening metathesis polymerization of cyclobutene-containing monomers based on the endo-tricyclo[4.2.2.0(2,5)]deca-3,9-diene structure bearing cyclic anhydride and N-alkyl- or N-phenylsubstituted succinimides at the 7- and 8-positions was investigated. Well-defined molybdenum and ruthenium complexes were used as catalysts. Cl2Ru(CHPh)(PCy3)(2) (III) was shown to be the most suitable catalyst as a well-controlled and even living polymerization was observed. Mainly cis stereochemistry (approximate to 75%) was observed in the main chain. Kinetic studies with different substituted succinimide moieties indicated that the polymerization rate depended on electronic effects in the monomer. F-19 NMR of fluorinated polymers suggests that through-space interactions between fluorine groups and the main polymer chain occur. These new polymers have a good thermal stability (304 degreesC < T-d < 344 degreesC). Upon hydrogenation, the N-methylsuccinimide functionalized polymer exhibited a T-g at 285 degreesC, and the thermal stability increased by about 100 degreesC.