Single-walled and multiwalled carbon nanotube blends with polyvinylidene difluoride (and its copolymers) have been characterized. The nanotubes are observed to form a well-dispersed, structurally random nanophase within the fluoropolymer matrix. X-ray analysis coupled with differential scanning calorimetry suggests that the nanophase alters crystal formation within the polymer. For most loadings and nanotube types, the piezoelectric β-polymorph is significantly enhanced over other crystal phases. Solution-cast composite thin films exhibit enhancements in both the pyroelectric response and mechanical transduction over pure polymer. This is interpreted as resulting from the change in crystallinity.

We have developed a new method of application of C60 to cultured cells that does not require water-solubilization techniques. Normal and malignant cells take-up C60 and the inherent photoluminescence of C60 is detected within multiple cell lines. Treatment of cells with up to 200 μg/ml (200 ppm) of C60 does not alter morphology, cytoskeletal organization, cell cycle dynamics nor does it inhibit cell proliferation. Our work shows that pristine C60 is non-toxic to the cells, and suggests that fullerene-based nanocarriers may be used for biomedical applications.

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We describe the preparation and characterization of a photonic crystal filled with a luminescent conjugated polyelectrolyte, sulfonated poly(phenylene ethynylene). The conjugated polymer was coated onto the nanospheres by the layer-by-layer method and assembled directly into a fluorescent opal structure avoiding the defects associated with post-filling schemes. These structures exhibit strong angle-dependent luminescent properties. By using multiple layers, we further demonstrate control over the emissive bands of the opal.