Jump to main content
Jump to site search


Self-assembly of Fluoride-encapsulated Polyhedral Oligomeric Silsesquioxane (POSS) nanocrystals

Abstract

The self-assembly and crystal packing of a unique series of nanocrystalline fluoride ion-encapsulated polyhedral oligomeric silsesquioxane compounds (F-POSS), with substituted electron-withdrawing group (EWG) perfluorinated alkyl chain arms of varying lengths was investigated. The fluorine-encapsulated T8[(CH2)n-EWG]8F—18-crown-6-ether-M+ and T8[(CH2)n-EWG]8F--tetrabutyl ammonium TBA+ compounds with fluorinated alkyl chain arms, were synthesized and subsequently analyzed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and simultaneous small- and wide-angle X-ray scattering SAXS/WAXS techniques. DSC and TGA of the compounds showed that the melting temperatures occurred below 100 °C and were thermally stable above their melting temperatures. SAXS/WAXS data probed the crystalline structure and self-assembly of the nanocrystalline compounds. At ambient temperatures, the crystalline structures of the compounds were seen to be complex with triclinic unit cells. On cooling from the melt, the self-assembly of the compounds with shorter fluorinated alkyl chain arms is dominated by the ionic attraction between the cages such that the arms form a disordered state that only reorder on standing. In contrast, the self-assembly of the compounds with longer fluorinated alkyl chain arms is dominated by the alignment of the arms into rod-like morphologies such that a fully ordered solid is formed from the melt. Electrical characterization has revealed that the POSS cages exhibited an insulating behavior. The POSS cages with or without fluoride ion encapsulation had similar AC conductivities but cages without fluoride ion encapsulation have the highest relative permittivity. The results show that due to the inorganic-organic-ionic nature the F-POSS ion encapsulated compounds and nanocrystalline self-assembly, they have great potential as interfacial compatibilizers enhancing miscibility of polymer composites and aiding interactions between polar and non-polar solvents as ionic liquids.

Back to tab navigation

Supplementary files

Publication details

The article was received on 13 Oct 2018, accepted on 30 Nov 2018 and first published on 01 Dec 2018


Article type: Paper
DOI: 10.1039/C8CE01750F
Citation: CrystEngComm, 2018, Accepted Manuscript
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    Self-assembly of Fluoride-encapsulated Polyhedral Oligomeric Silsesquioxane (POSS) nanocrystals

    E. Heeley, Y. El Aziz, C. Ellingford, A. Jetybayeva, C. Wan, E. Crabb, P. Taylor and A. Bassindale, CrystEngComm, 2018, Accepted Manuscript , DOI: 10.1039/C8CE01750F

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements