A high density plasma from a methane–hydrogen mixture is generated in an inductively coupled plasma reactor, and multiwalled carbon nanotubes (MWNTs) are grown on silicon substrates with multilayered Al/Fe catalysts. The nanotubes are vertically aligned, and the alignment is better than the orientation commonly seen in thermally grown samples. A detailed parametric study varying inductive power, pressure, temperature, gas composition, catalyst thickness, and power to the substrate is undertaken. Transmission electron microscopy and Raman spectroscopy are used to characterize the nanotubes. Emission spectroscopy and a global model are used to characterize the plasma. The power in the lower electrode holding the substrate influences the morphology and results in a transition from MWNTs to nanofibers as the power is increased.

Dynamic mechanical analysis is commonly used to characterize thermoset polymers at temperatures ranging from well below to well above their glass transition temperatures. Many sample fixtures are available; however, the best clamp and best sample dimensions for a given material are not often readily apparent. Five different epoxy amine networks with glass transitions spanning over 1008C were characterized on three-point bending, dual cantilever, and single cantilever clamps with both constant thickness and constant span-to-thickness. Glassy modulus values were accurately measured on all clamps provided span-to-thickness ratios >10 were maintained. Thermal expansion and decreasing sample stiffness with increasing temperature greatly affect measurements in the rubbery region resulting in single cantilever clamps being best suited to measure rubbery data.

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DGEBA was cured with bimodal blends of polyetheramines as well as with single molecular weight amines while maintaining stoichiometry. Glass transition temperatures (Tgs) and moduli were measured using dynamic mechanical analysis (DMA). Fracture properties were measured using the compact tension geometry and testing was performed at both ambient and non‐ambient temperatures, investigating toughness changes as a function of temperature. For constant amine average molecular weights, the addition of high molecular weight amines caused increased glassy moduli at a constant T − Tg and decreased densities while broadening the glass transition without changing the fracture toughness. The fracture behavior, specifically the slip‐stick to brittle transition, was affected by the broadened transitions. Tg, breadth of Tg, and total damping were found to be proportional to the volume fraction of amine in the system. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1621–1631, 2013