Tunable Thin Film Periodicities by Controlling the Orientation of Cylindrical Domains in Side Chain Liquid Crystalline Block Copolymers

Figure 3

(a) TEM micrographs showing the regular symmetric hexagonally packed cylindrical morphology of annealed PS-b-P6FMA bulk sample. Two phases noted as P1 and P2 are from top and side view of the cylinder structure, respectively. The bottom left inset in TEM images displays the Fourier-transform pattern of the real-space image and in P1 six periodic lengths of 10.6 nm with an averaged 60 intersection angle indicating symmetric hexagonal packed array are clearly revealed. (b) TEM micrographs showing the averaged 9.5 nm width lamellar morphology of annealed PS-b-P1FMA bulk sample. (c) TEM micrographs showing the averaged 12.4 nm width lamellar morphology of annealed PS-b-P4FMA bulk sample. The bright and dark region corresponds to PS and heavily ruthenium tetroxide-stained hydroxyl groups in fluorinated segments, respectively.

(a)

(b)

(c)