Abstract
A new confined
p-phenylenevinylene (PPV)-type polymer (PPVS) has been synthesized using Wittig condensation. The chemical structure of the polymer was well defined by
1H NMR,
13C NMR, and FTIR spectroscopic analysis. PPVS contains oligomeric PPV units separated by sulfide bridges in the main chain; it is fully soluble in common organic solvents and has a number-average molecular weight of 3500
g
mol
−1. Thermogravimetric analysis and differential scanning calorimetry indicate that PPVS is amorphous, stable up to 360
°C in air and displays a glass transition temperature of 98
°C. The optical properties of the polymer were investigated by UV–visible absorption and photoluminescence spectroscopies. The polymer film absorbs at 375
nm and emits at 517
nm with a narrow emission spectrum. From the cyclic voltammetry analysis, the electrochemical bandgap was estimated to be 2.78
eV. A single-layer diode device of the configuration indium-tin oxide/PPVS/aluminium has been fabricated and has a relatively low turn-on voltage of 3.4
V. An electroluminescent emission similar to photoluminescence is demonstrated in a multilayer device.