Figure 4: Controlling micelle length in hybrid constructions.

TEM images of the structures obtained by adding different amounts (a, 10 μl or b, 20 μl) of PFS₃₀-b-P2VP₃₀₀ in THF (10 mg ml⁻¹) to 2-PrOH solutions (1 ml) of seed-coated SiO₂ NPs (0.25 mg), then aging 24 h at room temperature. (c) Two-step micelle growth. Hybrid sunflower structures 4c with elongated petals obtained by adding an aliquot of PFS₃₀-b-P2VP₃₀₀ in THF (2.5 μl, 10 mg ml⁻¹) to a 2-PrOH solution (0.5 ml) of the sunflower assemblies 4a shown in a. (d) Larger structures 4d obtained by adding PFS₃₀-b-P2VP₃₀₀ in THF (10 μl, 10 mg ml⁻¹) to a 2-PrOH solution (0.5 ml) of the assemblies 4b shown in b. Both solutions were aged for 24 h after the second addition of PFS₃₀-b-P2VP₃₀₀. Scale bars, 500 nm.