Luminescent and Electrochromic PAs

Light-emitting phenomena are a characteristic of luminescence materials. Among the different types of luminescence, light-emitting aromatic PAs are of importance that produces electroluminescence (EL) or photoluminescence (PL) phenomena upon exposure to an electric current or due to absorption of photons 

Additionally, the film formation properties and outstanding mechanical properties of aramids make these polymers suitable for the production of organic light emitting diodes (OLEDs), and specifically polymer hght emitting diodes (PLEDs). Despite this, classical condensation polymers are rarely studied for these applications. Moreover, some luminescence materials also show electrochromism (EC), a phenomenon in which materials exhibit a reversible change in optical properties when they are oxidized and reduced. Electrochromic materials are now been exploited in diverse applications such as mirrors, displays, windows, and earth-tone chameleon materials [95]. 

DMA solution and 295-345 in the solid (film) state, and their PL spectra exhibited maximum bands at 452-456 nm in the purple-to-green region in DMA solution, and 451-520 in the films. The films showed high optical transparency, with cut-off wavelengths in the range of 296-391 nm. Moreover, the PA-28c exhibited excellent elec-trochromic contrast and coloration efficiency, changing from the colorless neutral form to green, and then to dark blue upon oxidation (potentials from 0.00 to 1.35 V). 

Rules and Regulations Under the Textile Fiber Products Identification Act http //www.ftc.gov/os/statutes/textile/rr-textl. pdf). Part 303.7 (Generic names and definitions for manufactured fibers), US Federal Trade Commission (FCT) 2002. 

Nasr-Isfahani, K. Faghihi, and N. Valikhani, Journal of Applied Polymer Science, Vol. Ill, p. 1769,2009. 

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