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Polyurethane/organophilic montmorillonite (PU/OMT) nanocomposites based on polyether, organophilic montmorillonite, phenylmethane diisocyante, diglycol, and glycerine were synthesized and characterized by x-ray diffraction (XRD). Delaminated or intercalated structures in polyurethane/OMT nanocomposites with different OMT content were found. The mechanical, thermal, and inflammability properties of PU/OMT nanocomposites were investigated through tensile, thermogravimetry, differential scanning calorimetry, and cone calorimetry experiments. It is shown that polyurethane/OMT nanocomposites have enhanced tensile strength, improved thermal stability, and flame retardant properties relative to bulk polyurethane. The tensile strength of PU/OMT with 4.7 wt% OMT content was double compared to that of bulk PU. The thermal and flame retardant properties of PU/OMT were enhanced compared to that of bulk PU. The thermal and flame retardant properties of PU/OMT increased with increasing OMT content. [ABSTRACT FROM AUTHOR]

In the present work, a facile compounding and electrospinning method was used to prepare PAN/Fe-OMT composite nanofibers. Electrospinning solution properties including viscosity, surface tension, and conductivity were measured and combined with the results of Fourier transform-infrared (FT-IR) spectra, high-resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM) to investigate the effects of Fe-OMT on the structure and morphology of electrospun PAN nanofibers, respectively. It was found from FT-IR and HRTEM that the silicate clay layers were well dispersed within the composite nanofibers and were oriented along the fiber axis. The SEM images indicated that the loading of Fe-OMT decreased the average diameters of composite nanofibers due to the increased conductivity of composite solutions. Then, the prepared PAN nanofibers and PAN/Fe-OMT composite nanofibers were further pre-oxidized and carbonized. The effects of Fe-OMT on the structure and morphology of PAN-based carbon nanofibers were also investigated by FT-IR and SEM. The FT-IR spectra indicated that there were different characteristic absorption peaks for pure PAN nanofibers and PAN/Fe-OMT composite nanofibers during the pre-oxidation and carbonization processes. The SEM images revealed that the morphology of nanofibers underwent marked changes before and after carbonization. The Fe-OMT loadings might promote the dehydrogenation, cyclization, and cross-linking reactions of the PAN composite nanofibers during carbonization. [ABSTRACT FROM AUTHOR]