Electroluminescent (EL) devices operating at alternating current (AC) electricity have been of great interest due to not only their unique light emitting mechanism of carrier generation and recombination but also their great potential for applications in displays, sensors, and lighting. Despite great success of AC–EL devices, most device properties are far from real implementation. In particular, the current state-of-the art brightness of the solution-processed AC–EL devices is a few hundred candela per square meter (cd m–2) and most of the works have been devoted to red and white emission. In this manuscript, we report extremely bright full color polymer AC–EL devices with brightness of approximately 2300, 6000, and 5000 cd m–2 for blue (B), green (G), and red (R) emission, respectively. The high brightness of blue emission was attributed to individually networked multiwalled carbon nanotubes (MWNTs) for the facile carrier injection as well as self-assembled block copolymer micelles for suppression of interchain nonradiative energy quenching. In addition, effective FRET from a solution-blended thin film of B-G and B-G-R fluorescent polymers led to very bright green and red EL under AC voltage, respectively. The solution-processed AC–EL device also worked properly with vacuum-free Ag paste on a mechanically flexible polymer substrate. Finally, we successfully demonstrated the long-term operation reliability of our AC–EL device for over 15 h.

Printable non-volatile polymer memories are fabricated with solution-processed nanocomposite films of poly(styrene-block-paraphenylene) (PS-b-PPP) and single-wall carbon nanotubes (SWNTs). The devices show stable data retention at high temperatures of up to 100 °C without significant performance degradation due to the strong, non-destructive, and isomorphic π-π interactions between the SWNTs and PPP block.

The development of polymer-filled composites with an extremely high thermal conductivity (TC) that is competitive with conventional metals is in great demand due to their cost-effective process, light weight, and easy shape-forming capability. A novel polymer composite with a large thermal conductivity of 153 W m(-1) K(-1) was prepared based on self-assembled block copolymer micelles containing two different fillers of micron-sized silver particles and multi-walled carbon nanotubes. Simple mechanical mixing of the components followed by conventional thermal compression at a low processing temperature of 160 °C produced a novel composite with both structural and thermal stability that is durable for high temperature operation up to 150 °C as well as multiple heating and cooling cycles of ΔT = 100 °C. The high performance in thermal conduction of our composite was mainly attributed to the facile deformation of Ag particles during the mixing in a viscous thermoplastic medium, combined with networked carbon nanotubes uniformly dispersed in the nanoscale structural matrix of block copolymer micelles responsible for its high temperature mechanical stability. Furthermore, micro-imprinting on the composite allowed for topographically periodic surface micropatterns, which offers broader suitability for numerous micro-opto-electronic systems.

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