POLY 555 |
| This article reports a new polymerization technique for the functionalization of the vinyl-type polynorbornene via the copolymerization of norbornene (N) with styrene (S) in polar solvents like dichlorobenzene catalyzed by a substituted ansa-fluorenylamidodimethyltitanium activated with a suitable cocatalyst. The resulting copolymers possess much higher molecular weights and stereoregularity comparable with those of the copolymers obtained from the nickel-based catalysts. Because of the specific molecular structure of the vinyl-type N-S copolymers that composed of positive birefringence and highly rigid norbornene rings in combination with negative birefringence styrene units, the titanium-based N-S copolymers exhibited superior optical properties than that of PMMA or PC, and exceptionally high heat resistance property up to 300 oC comparable with that of the commercial engineering plastics. |
|
General Papers: Functional Materials
8:00 AM-12:00 PM, Wednesday, August 22, 2007 Westin Boston Waterfront -- Douglas, Oral
Division of Polymer Chemistry |