Triblock copolymers via ring opening metathesis polymerization using organometallic bimetallic initiators

INOR 202

Rojendra Singh, roje@mit.edu, Department of Chemistry, MIT, 77 Mass. Ave., 6-420, Cambridge, MA 02139 and Richard R. Schrock, rrs@mit.edu, Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-331, Cambridge, MA 02139.
The first series of bimetallic ROMP initiators of the type 1-4-[(DME)(RF6O)2(ArN)MCH]2C6H4 and 1-4-[(RO)2(ArN)MoCH]2C6H4 (M = Mo and W, Ar = 2,6-diisopropylphenyl, OR=OCMe3, ORF6=OC(CF3)2Me) have been synthesized. Initiation of both alkylidene groups within each catalyst was established by the polymerization of cyclic olefins using 1H-NMR studies. Polymerization reactions with the difunctional initiators were conducted to obtain both homopolymers and triblock (ABA) copolymers. The catalysts showed living behavior yielding polymers with narrow polydispersities. A substituted norbornene, with a liquid crystal moiety was synthesized and polymerized, to be used as a central low Tg block in a ABA type triblock copolymers. The triblock copolymers showed significant phase separation based on DSC studies. The polymers prepared were also analyzed for their mechanical, optical and thermodynamic properties.
 

Organometallic General and Catalysis
7:00 PM-9:00 PM, Sunday, 13 March 2005 Convention Center -- Hall D, Poster

Division of Inorganic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005