Preparation of size-controlled cross-linked fluoroalkyl end-capped oligomer/gold nanocomposites

Cross-linked fluoroalkyl end-capped cooligomeric nanoparticles, which were prepared by reaction of fluoroalkanoyl peroxide with poly(oxyethylene) unit-containing dimethacrylate monomer and acrylic acid, were applied to the preparation of novel cross-linked fluorinated cooligomer/gold nanocomposites. These fluorinated gold nanocomposites were prepared by reactions of gold ions with poly(methylhydrosiloxane) in the presence of the corresponding fluorinated nanoparticles in 1,2-dichloroethane at room temperature. The size of these fluorinated gold nanocomposites thus obtained is nanometer size-controlled, and the absorbance around 530 nm related to the formation of gold nanoparticles was found to increase by the addition of trioctylamine under these preparative conditions. The size of these composites increased effectively from 67 nm to 160 nm levels with increasing the amounts of trioctylamine. In particular, the plasmon absorption bands related to the gold nanocomposites were also dramatically red-shifted from around 530 nm to 900 nm levels under similar conditions.