Fig. 3. Kinetic study of the formation of the toroids constituting the multi-tori mesostructures.

Six vials were prepared. In each vial, 20 μl of a decane solution of PFS₅₅-b-PI₅₀₀ seeds (c = 0.2 mg ml⁻¹) was added to 1 ml of acetone/decane mixture. The solution was then left to equilibrate at 35°C, and an aliquot of PFS₂₆-b-PS₃₀₆ dissolved in THF (8 μl, c = 10 mg ml⁻¹) was injected. The solution was then annealed at 35°C. Samples were taken out from the solution and deposited on a TEM grid 30 s (A), 5 min (B), 10 min (C and D), 20 min (E), 30 min (F), and 1 hour (G and H) after injection of PFS₂₆-b-PS₃₀₆ unimer. The red arrows in (B) point at the elongated micelles that started to appear in the drupelets after 5 min of annealing. Scale bars, 100 nm (A, B, F, and H) and 200 nm (C to E and G).