Synthesis, molecular and morphological characterization of second generation dendritic copolymers of butadiene and isoprene with different microstructures

POLY 193

Apostolos Avgeropoulos, aavger@cc.uoi.gr1, Sofia Rangou1, Edwin L. Thomas2, and Vahik Krikorian3. (1) Department of Materials Science & Engineering, University of Ioannina, University Campus - Dourouti, Administration Building, Ioannina -45110, Greece, (2) Institute for Soldier Nanotechnologies and Department of Materials Science and Engineering, Massachusetts Institute of Technology, Room NE47-581, 77 Massachusetts Avenue, Cambridge, MA 02139, (3) Department of Material Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
We report the synthesis of well-defined 2nd generation dendritic copolymers consisting of polybutadiene (PB) of 1,4 microstructure and polyisoprene enriched in 3,4 microstructure (at least 55% PI3,4). The preparation of these materials was achieved via anionic polymerization techniques in combination with chlorosilane chemistry potentials. The molecular characterization of the final dendritic materials was made via Size Exclusion Chromatography (SEC), Membrane and Vapor Pressure Osmometries (MO and VPO respectively), Dilute Solution Viscometry and 1H-Nuclear Magnetic Resonance (NMR) Spectroscopy, leading to the conclusion that they can be considered model polymers. Morphological studies on the copolymers have proven that the two dienic branches exhibit microphase separation leading to the observation via TEM (Transmission Electron Microscopy) instrumentation of hexagonally close packed cylinders consisting of the 1st generation chains (minority) in a matrix of the 2nd generation segments (majority).

 

General Papers: Polymers in Nanotechnology
6:00 PM-8:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007