conjugated polymers - metathesis - nanoparticles
Significance
<P>Nanoparticles of a conjugated poly(phenylene vinylene) (PPV) were synthesized by
step-growth polymerization of a divinyl monomer in an aqueous emulsion. Model studies
in toluene revealed that the Hoveyda-Grubbs metathesis catalyst afforded the highest
yield (>95%) of moderately high molecular weight PPV (Mn 2400 g/mol); additionally,
the optimal monomer/catalyst ratio was also determined. Using these conditions, approximately
230 nm-sized PPV nanoparticles were synthesized within surfactant-stabilized toluene
microemulsions in water.</P>
Comment
<P>Dispersions of conjugated polymer nanoparticles have been shown to possess superior
processability over simple polymer solutions (Scherf et al.
Nat. Mater. 2003,
2, 408). Moreover, nanoparticles open the door to using conjugated organic polymers
in a host of bioimaging applications. In this paper, the authors present a unique,
‘bottom-up’ method of synthesizing PPV nanoparticles. Whereas it is most common to
form conjugated polymer nanoparticles by crosslinking individual polymer chains,
the authors perform the reverse by growing polymer chains within a micelle.</P>
