Other Conjugated Polymers and Polymer Blends

Interfaces with Other Conjugated Polymers and Polymer Blends 

Devices constructed using multilayered structures of PPV derivatives and emeraldine base polyaniline layers were also reported [208]. 

Polyaniline Blends. Polyaniline doped with camphor sulfonic acid, PANI-CSA, in the form of a blend with poly(methyl methacrylate), PMMA, is also used as hole injection material in PPV-based LEDs owing to the low barrier for hole injection [209,210] and the match of the PPV electroluminescent emission with the transmittance window of the PANI-CSA/PMMA blend (Fig. 10). Blends of polyester resin (PES) with PANI-CSA were also used for this purpose [209]. The barrier height for hole injection at the PANI-CSA-PES/MEH-PPV blend was found to be dependent on the PANI-CSA concentration, ranging from about 0.02 eV at a concentration of 5% w/w to about 0.1 eV for pure PANI [209]. In the case of PANI-CSA-PMMA/PPV interfaces, the barrier height for hole 

Polyaniline also presents an additional potential advantage because uniaxially oriented blends of polyaniline doped with dode-cylbenzenesulfonic acid or CSA and common bulk polymers such as polyacrylonitrile, polyethylene, and poly(vinyl alcohol) display a polarizing efficiency over the range from 400 to 4000 cm that matches, or surpasses, that of commercial wire grid polarizers [211]. These characteristics permit the use of polyaniline simultaneously as a polarizer and as an anode. 

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