A surfactant-encapsulated polyoxometalate complex SEP-PMo was prepared by phosphomolybdic acid (H3PMo12O40

abbreviated as HPMo)

via electrostatical interaction between HPMo and N-[12-(4-carboxylphenoxy)dodecyl]-N

N-dimethylammonium bromide (CDDA). The resulting complex was characterized in detail by elemental analysis

thermogravimetric analysis (TGA)

as well as FT-IR spectra. SEP-PMo was further complexed with poly(4-vinyl pyridine) (P4VP) via hydrogen bonding interaction to get P4VP(SEP-PMo)n(n=0.01

0.05

0.1

0.3

0.5 and 1). Mesomorphic phase behaviors of CDDA

SEP-PMo as well as P4VP(SEP-PMo)n were studied by a combination of differential scanning calorimetry (DSC)

polarized light microscopy (PLM)

small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Surfactant CDDA has a bilayer smectic A structure with a layer thickness about 4.8 nm. When increasing the temperature to 140℃

the phase structure turns into a monolayer smectic A structure with a layer thickness around 2.4 nm. SEP-PMo exhibits thermotropic liquid crystal phase behavior induced by microphase separation from organic and inorganic composites. SAXS and TEM studies revealed that SEP-PMo could form lamellar structure with the layer thickness about 2.5 nm

and within the layer PMo has relatively ordered structure. Comparing with the phase structure of P4VP-PMo-n composites

the mesophase structure of SEP-PMo could be partially kept in the hydrogen bonded complex

P4VP(SEP-PMo)n.