A delicate maneuver on conjugated rod-rod structures composed of poly(3-hexylthiophene) and polyaniline subtending patched-fibrillar,ringed-fibrillar,double-fibrillar and sandwiched configurations

Full-conjugated rod-rod structures comprising patched-fibrillar, ringed-fibrillar, and double-fibrillar configurations were designed from poly(3-hexylthiophene) (homo-P3HT) and polyaniline (PANI) nanorods in chloroform, p-xylene, and amyl acetate dilute solutions, respectively. Solvent quality, seeding effect, and constituent material were focused while characterizing the developed structures. By exacerbating the processing solvent quality from chloroform to p-xylene, a ringed-fibrillar configuration was detected instead of patched-fibrillar structure. In a poor solvent, double-fibrillar structures were acquired from homo-P3HT chains and PANI nanorods. Towards a poorer solvent, P3HT chains were capable of developing their own crystals by less sensing presence of PANI nanorods as seeds. In another experiment, by copolymerization of both P3HT and PANI with crystallizable PEG blocks, sandwiched rod-rod mixed-brush single crystals were developed. Molecular weight of neither P3HT nor PANI was effective on surface patterning of P3HT/PANI mixed-brushes. Via elevating crystallization temperature, PANI dispersed patterns became more delicate and their width decreased from 80 to 160 nm to 12–30 nm. P3HT backbones were tethered with a extended flat-on orientation onto the PEG substrate at either low or high crystallization temperatures. Beside sandwiched single crystals seeded with homo-PEG tiny crystals, slightly and highly curved half-ring crystals were also developed in the PEG-b-P3HT systems.

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