Abstract
The preparation of gold nanoparticles incorporated in self-assembled and ordered semifluorinated poly(ethylene oxide)-b-poly(1H,1H-dihydroperfluorooctyl methacrylate) (PEO-b-PFOMA) thin films was explored through annealing induced phase transition. The micellar thin films containing gold nanoparticles whose average size was dependent on the block length of the copolymer were produced by spin casting the solution of PEO10k-b-PFOMA12k and PEO20k-b-PFOMA22k in chloroform with a gold precursor, LiAuCl4. Three annealing modes were attempted for the Au-loaded micellar films: solvent vapor annealing, supercritical CO2 at 70°C and thermal annealing at 100°C. The nanoparticles dispersed in PEO regions were forced to follow the morphological change of the PEO phase and grew into larger single particles in PEO domains. The solvent annealing produced higher ordering of Au nanoparticles than scCO2 or thermal annealing.
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► Gold nanoparticles were formed in the PEO phase of PEO-b-PFOMA micellar films. ► Annealing methods were examined for morphology transition of the hybrid films. ► The gold nanoparticles followed the morphological transition of the PEO phase. ► Crystal growth of the nanoparticles was investigated through the phase transition.