We have developed a simple, efficient process for solubilization of single-wall carbon nanotubes (SWNTs) with amylose in aqueous DMSO. This process requires two important conditions, presonication of SWNTs and subsequent amylose treatment in an optimum mixture of DMSO/H2O. The former step separates SWNT bundles, and the latter step provides a maximum cooperative interaction of SWNTs with amylose, leading to the immediate and complete solubilization. The best solvent condition for this is around 10-20% DMSO, in which amylose assumes a random conformation or an interrupted helix. This indicates that the amylose helix is not the prerequisite for encapsulation of SWNTs. The SEM and AFM images of the encapsulated SWNTs manifest loosely twisted ribbons wrapping around SWNTs, which are locally intertwined as a multiple twist, but no clumps of the host amylose are seen on SWNT capsules.

The J-aggregation of Cyanine-1dye in the presence of carboxymethyl amylose (CMA) is described. The J-aggregation requires a large excess CMA concentration; the J-band maximum appears in the concentration range, [CMA]/[dye] = 10-50, depending on the degree of substitution (DS) of carboxylation, where [CMA] is the concentration of polymer repeat units. An extraordinarily large induced circular dichroism (CD) is observed from J-aggregates of the achiral cyanine dye in association with a random coil CMA, suggesting that the CMA is transformed into a helix. The magnitude of CD intensity increases with increasing DS of CMA and pH up to neutral (where a maximum J-aggregation occurs), while the CMA-bound dye monomer and H-aggregates (occurring at pH > or = 9) exhibit no induced CD. The trend in the CD intensity (of the J-aggregates) is in parallel with the fluorescence intensity of the J-aggregates. This suggests that binding of the J-aggregates onto the template CMA is sterically controlled by the asymmetric environment of glucose residues (of CMA) so that more twisting power is exerted with increasing DS (of CMA), rendering the cyanine dye/CMA complex a more rigid (a high fluorescence intensity) super-helix. This is also revealed by the AFM image of a long strand.

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Fluoromethylene cyanate ester resins derived from the monomer series N⋮CO−CH2(CF2) n CH2−OC⋮N (where n = 3, 4, 6, 8, and 10) have been synthesized and characterized. Monomer melting points range from −8 to 181 °C, and characterization includes 1H, 13C, and 19F NMR and IR spectroscopy and DSC. Purification is a critical requirement for melt processing. The thermal curing reaction is a cyclotrimerization reaction of the cyanate functional group to the cyanurate heterocycle. Physical properties of resin castings and their variation with an increase in fluoromethylene sequence length from 3 to 10 CF2 units include density, 1.77−1.91 g/cm3; critical surface tension, 40−23 dyn/cm; refractive index, 1.447−1.382; dielectric constant, 2.7−2.3; 100 °C immersion water absorption, 1.67−0.68%; T g, 84−101 °C; glass/rubber thermal expansion coefficient, (109/238−152/275 ppm/ °C; and gravimetric thermal stability, 0.0196−0.0064% weight loss/min at 300 °C). Compared with aromatic cyanate ester resins, the fluoromethylene cyanate esters have significantly lower T g, dielectric constant, critical surface tension, and water absorption. For low-dielectric applications, the optimum trade-off between properties and processing occurs at a fluoromethylene chain length of 6.