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Due to cross‐linked structures, thermoset polymers cannot provide sufficient free volume for nanofillers to maneuver. Related composites are therefore governed by phase separation where filler‐deficit regions become mechanical weakness. This work discovers that carbon nanotubes can be redispersed in thermoset polymer through heat treatments, thus, enhancing strength, thermal, and electrical conductivity of composites. Experiments carried out on a different thermoset matrix gives a similar trend where heating induced tube displacement is also verified by molecular dynamic simulations and piezo‐resistivity tests. [ABSTRACT FROM AUTHOR]

Due to oxygenation, carbon nanotubes cannot operate field emission for a long period of time. So far, the emission-induced oxygenation mechanism has not been studied in detail; particularly, the underlying mechanism that causes a drastic increase of the emitting current contiguous to the turn-on voltage remains unclear. Cold plasma is a nonthermal equilibrium process and can also oxygenate carbon materials through radiolysis. In this work, electrical measurements of single-walled carbon nanotubes are in situ carried out in O2 and N2 plasma irradiation, and the tube resistance due to irradiative damages is found to increase in three steps, defined as regions I, II, and III. In region I, the increase is rapid and involves extraction of intercalated O2 between the nanotubes. The nanotubes become severely oxygenated in region II, thus enhancing the on-tube scattering and resistance. Nanotube segmentation takes place in region III, where the opened edges are likely bonded with oxygenated and nitride groups. Experimental data successfully explain the field emission instability of carbon nanotubes, including a low life cycle, sudden increase in emitting current around the turn-on voltage, and thermal decomposition of carbon lattices. [ABSTRACT FROM AUTHOR]