The renewable triphenols, resveratrol and dihydroresveratrol, were used in the preparation of two new phthalonitrile resins (PN), each containing three phthalonitrile groups. These are the first reported PN resins generated from a renewable feedstock. These amorphous PN resins were characterized thoroughly by DSC, NMR spectroscopy and rheometry. The monomers exhibited excellent rheometric viscosities suitable for resin transfer molding and resin infusion molding. After complete cure, the PN polymers exhibited thermal stability to above 500 8C and no glass transition temperature (T g ). As a result of the highly cross-linked nature of the network, these materials exhibited a low water uptake of 1 AE 0.2 % and dielectric constant values of approximately 3.0. These results suggest that resveratrol-derived PN resins are excellent candidates for use in maritime environments and aerospace applications.[a] Dr.

The sustainable resveratrol-based phthalonitrile was used in the preparation of E-glass fiber-reinforced phthalonitrile composite panels fabricated by hot pressed prepreg consolidation with bis[4-(3-aminophenoxy)phenyl]sulfone (m-BAPS) as the curing additive. This amorphous monomer exhibited excellent viscosities at temperatures below 200 8C, which is applicable to standard processing conditions. Rheometric measurements were used to evaluate the cure of the composite as a function of the postcure conditions. The composite retains >95% of its room temperature storage modulus up to 450 8C based on these postcuring parameters. More importantly, flammability performance of the composite-which was determined in terms of ignitability, heat release, and mass loss rate-excels over other state-of-the-art polymer/glass composites. Even under the most extreme heat fluxes (e.g., 100 kWÁm 22 ), the composite performs exceptionally well suggesting that resveratrol-based phthalonitrile composites can be used in fire-resistant applications.

The question of why different races appear more susceptible to hair contamination by external drugs remains controversial. This research studied susceptibility of head hair to external cocaine and methamphetamine when hair products have been applied. Three different chemical classes of ethnic hair products were applied to Caucasian, Asian, and African hair. Some products increased the methamphetamine and cocaine concentrations in all hair types. A unique finding of this research is that certain ethnic hair products can replace moisture as a diffusion medium, thereby increasing the susceptibility to contamination over 100-fold compared to petroleum-based products.

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