Morphology control between microspheres and nanofibers by solvent-induced approach based on crosslinked phosphazene-containing materials

Multi-morphology control between monodisperse microspheres and uniform nanofibers was successfully achieved by adjusting the ratio of solvent composition. Through the condensation polymerization between hexachlorocyclotriphosphazene and 4,4′-sulfonyldiphenol, the corresponding hybrid inorganic–organic materials appeared. The morphology of both microspheres and nanofibers contained excellent size and shape: the monodisperse microspheres with 0.7–0.9 μm in diameter and the uniform nanofibers with 60 nm in outer diameter. We applied the concept of three-dimensional Hansen solubility parameters for the initial explanation. The activity of the primary colloid particles and the solubility of triethylamine–hydrogen chloride crystal were considered as two factors for the mechanism explanation. This interesting research shows that the nano- and micro-materials with high crosslinked molecule structure and prepared by condensation polymerization can also achieve the morphology transition. It fills the blank in nano-morphology transition research and will provide great information for the research about the control of different morphology preparations based on polymer nanomaterials.