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Abstract— Carbon‐nanotube (CNT) films on plastic are incorporated as the touch electrode in a four‐wire resistive touch panel. Single‐point actuation tests show superior mechanical performance to ITO touch electrodes, with no loss of device functionality up to 3 million actuations. Sliding‐stylus‐pen tests reveal no loss of device linearity after 1 million stylus cycles. A CNT refractive index of ∼1.55 leads to CNT touch panels with low reflection (<9% over the visible range) without costly anti‐reflective coatings. CNT films on PET currently have 86% total transmission (including the PET) over the visible and 600 Ω/□, with lab scale tests giving 88% at 500 Ω/□. CNT films are neutrally colored (a* ∼ 0, b* ∼ 1.5), low haze (<1%), uniform, and both chemically and environmentally stable. Unidym's solution‐based coatings can be printed directly onto both flexible and rigid polycarbonate using solution coating processes. Unidym films can be patterned using subtractive methods such as laser ablation with resolution down to 10 μm, or additive methods such as patterned gravure. CNTs are grown, purified, formulated into inks, and coated using scalable processes, allowing films to be attractive from a cost perspective as well.

Nonuniform fields decrease the accuracy of dielectric characterization by microwave cavity perturbation. These fields are due to the slot in the cavity through which the sample is inserted and the boundary between the sample and the metallic walls inside of the cavity. To address this problem, we measured the natural frequency and damping ratio of a resonant cavity as a sample is inserted into the rectangular cavity. We found that for a range of cavity filling fractions, a linear regression on the natural frequency and damping ratio versus the effective volume fraction of the sample in the cavity could be used to extract the complex permittivity of the sample. We verified our technique by measuring a known quartz substrate and comparing the results to finite-element simulations. When compared to the conventional technique, we found a significant improvement in the accuracy for our samples and measurement setup. We confirmed our technique on two lossy samples: a neat stoichiometric mixture bisphenol A epoxy resin and one containing a mass fraction of 3.5% multi-walled carbon nanotubes (MWCNTs). At the mode (7.31 GHz), the permittivity and loss tangent of the epoxy were measured to be and , respectively. The epoxy with a mass fraction of 3.5% MWCNTs had a permittivity of and loss tangent of .Index Terms-Bisphenol A epoxy, metrology, microwave, multi-walled carbon nanotubes (MWCNTs), nanocomposites, noncontact, nondestructive, resonator.

Carbon nanotube (CNT) reinforced polymers are next-generation, high-performance, multifunctional materials with a wide array of promising applications. The successful introduction of such materials is hampered by the lack of a quantitative understanding of process-structure-property relationships. These relationships can be developed only through the detailed characterization of the nanoscale reinforcement morphology within the embedding medium. Here, we reveal the three-dimensional (3D) nanoscale morphology of high volume fraction (V(f)) aligned CNT/epoxy-matrix nanocomposites using energy-filtered electron tomography. We present an automated phase-identification method for fast, accurate, representative rendering of the CNT spatial arrangement in these low-contrast bimaterial systems. The resulting nanometer-scale visualizations provide quantitative information on the evolution of CNT morphology and dispersion state with increasing V(f), including network structure, CNT alignment, bundling and waviness. The CNTs are observed to exhibit a nonlinear increase in bundling and alignment and a decrease in waviness as a function of increasing V(f). Our findings explain previously observed discrepancies between the modeled and measured trends in bulk mechanical, electrical and thermal properties. The techniques we have developed for morphological quantitation are applicable to many low-contrast material systems.

Based on self‐assembly and mimicking strategies occurring in nature, peptide nanomaterials play a unique role in a new generation of hybrid materials for the electronics of the 21st century. This report describes the functionalization of diphenylalanine (FF)‐based micro/nanostructures with blue‐emitting conducting polymers of the polyfluorene (PF) family. The FF:PF polymer nanocomposites are synthesized by a liquid‐vapor phase method. Electron microscopy images reveal di‐octyl‐substituted PF (PF8) to bind better to the FF micro/nanotubes in comparison with ethyl‐hexyl PF (PF2/6), which influences its optical properties. Molecular dynamics simulations of FF nanotubes with monomeric units of PFs show that PF8 favors greater proximity to the grooves on the surface of the nanotubes due to a higher van der Waals interaction energy compared to PF2/6. The FF:PF nanocomposites are further utilized in light‐emitting diodes. Biodegradability tests from FF:PF8 nanocomposite films show more than 80% weight loss in 2 h by enzymatic action compared to PF8 pristine films, which do not degrade. Self‐assembly of FF nanostructures with organic semiconductors opens up a new generation of biocompatible and biodegradable materials in organic electronics.

The utility of gold nanorods for plasmonic applications largely depends on the relative orientation and proximity of the nanorods. Though side-by-side or chainlike nanorod morphologies have been previously demonstrated, a simple reliable method to obtain high-yield oriented gold nanorod assemblies remains a significant challenge. We present a facile, scalable approach which exploits meniscus drag, evaporative self-assembly, and van der Waals interactions to precisely position and orient gold nanorods over macroscopic areas of 1D nanostructured substrates. By adjusting the ratio of the nanorod diameter to the width of the nanochannels, we demonstrate the formation of two highly desired translationally ordered nanorod patterns. We further demonstrate a method to transfer the aligned nanorods into a polymer matrix which exhibits anisotropic optical properties, allowing for rapid fabrication and deployment of flexible optical and electronic materials in future nanoscale devices.

Self-Assembly Understanding the 3D structure of self-assembled block copolymer fi lms is essential to their applications in nanolithography. The 3D microdomain structure of a block copolymer consisting of polydimethylsiloxane cylindrical domains in a polystyrene matrix, templated by posts, is determined by TEM tomography. The cylinders form a cross-point array (left), which is compared with the predictions of self-consistent fi eld theory (right). www.afm-journal.deAdv. Funct. Mater. 2014, 24, 7564-7569

Phase equilibria of the Al2O3–CaO–FeO–SiO2–V2O3 system in synthetic slag mixtures simulating coal–petcoke slag chemistry at 1500 °C in an oxygen partial pressure of 10–8 atm were investigated by a series of quench experiments. Quenched samples were analyzed by inductively coupled plasma optical emission spectrometry (ICP), X-ray diffractometry (XRD), transmission electron microscopy (TEM), and wavelength dispersive X-ray (WDX). Two precipitated crystal phases were identified in molten slags: mullite (3Al2O3·2SiO2) in Al2O3-rich slags and karelianite (V2O3) in V2O3-rich slags. Scanning electron microscopy and TEM diffraction patterns confirmed the presence of the mullite and karelianite phases. On the basis of experimental results, an isothermal phase diagram of the Al2O3–CaO–FeO–SiO2–V2O3 system at 1500 °C and P O2 = 10–8 atm is proposed while keeping CaO = 7.0 wt % and FeO = 13.5 wt %.