Polynorbornene
“Norbornene or norbornylene or norcamphene is a bridged cyclic hydrocarbon. It is a white solid with a pungent sour odor. The molecule consists of a cyclohexene ring bridged with a methylene group in the para position. The molecule carries a double bond which induces significant ring strain and significant reactivity.”
“Norbornenes are important monomers in ring-opening metathesis polymerizations (ROMP) with for instance the Grubbs' catalyst. Polynorbornenes are polymers with high glass transition temperatures and high optical clarity.”
Recent US Patents
Hydrogen-Bonding-Induced One-Handed Helical Polynorbornenes Appended With Chiral Alaninegland
(2328–2338) Macromolecular Chemistry and Physics 212 #21 (2011)
Kao et al of the National Taiwan University, Taiwan, synthesized polynorbornenes appended with anthracene and chiral alanine linkers. Hydrogen bonding between the adjacent bisamidic linkers brings adjacent anthracene chromophores in a more suitable orientation for exciton coupling and renders one-handed helical structures for these polymers. Excimer formation is observed from their emission spectra. Monoamidic linkers provide only one hydrogen bond, which would be less robust and result in much lower circular dichroic response. (RDC 11/3/2011)