Figure S1-1. (a) Partial Density of States (PDOS) of Ti-graphene I-V model.

We report on the interfacial structure, the current−voltage (I−V) characteristics, and contact resistance of metal electrode−carbon nanotube contacts for five metals, Ti, Pd, Pt, Cu, and Au, based on first-principles quantum mechanical density functional and matrix Green's function methods. We find that Ti leads to the lowest contact resistance followed by Pd, Pt, Cu, and Au. The sequence, Ti ≫ Pd > Pt > Cu > Au, correlates well with the predicted cohesive strength of the electrode−carbon interface. In addition Ti leads to linear I−V characteristics up to ∼1 V, suggesting an Ohmic contact for both metallic and semiconductor nanotubes. However, the high reactivity of the Ti electrode at the contact to the nanotube distorts the nanotube structure.

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The microphase structure of noncrystalline poly(ethylene-co-13.3 mol % methacrylic acid) (E-0.133MAA) ionomers was investigated by using infrared (IR) spectroscopic, X-ray scattering, differential scanning calorimetric (DSC), and dielectric measurements. The noncrystallinity was confirmed by small-angle X-ray scattering (SAXS) and DSC studies, which has enabled a quantitative analysis of the SAXS ionic peak associated with ionic aggregates without being perturbed by the polyethylene lamellae peak. In 60% neutralized Na ionomer, it was revealed that almost 100% of MAA side groups including unneutralized COOH are incorporated into the ionic aggregates with an average ionic core radius (R 1) of ∼6 Å. The dielectric relaxation studies showed that the ionic aggregates form a microphase-separated ionic cluster. Analysis of dielectric strengths indicated the most (∼90%) of the COONa groups are present in the ionic cluster. On the other hand, in the 60% neutralized Zn ionomer, both SAXS and dielectric studies indicated that the ionic aggregates with R 1 ∼ 4 Å are almost isolated and dispersed in the matrix; the formation of ionic cluster was not recognized. Similarly to partly crystalline E-MAA ionomers, all noncrystalline E-0.133MAA ionomers exhibited an endothermic peak at 320−330 K (labeled T i) on the first heating, depending on the aging time at room temperature. Several factors that would be critical for the DSC T i peak were discussed. It was concluded that the DSC T i peak is certainly associated with changes of the state of ionic aggregate region.