Optical properties of poly(p-phenylene vinylene) derivatives with ion-coordinating side groups

The optical properties of poly(p-phenylene vinylene) (PPV) derivatives with ion-coordinating side groups (ICSG) films and respective blends with poly(ethylene: oxide) (PEO) complexed with lithium triflate are studied by means UV-visible absorption and photoluminescence (PL) spectroscopy. These PPV-derivatives were synthesized with the objective to improve the physical properties of PPV-derivative: PEO: lithium salt blends to be used in light emitting electrochemical cells (LECs). We have synthesised two homopolymers: the poly(2-methoxy, 5-(triethoxymethoxy)-1,4-phenylene vinylene) (MTEM-PPV) and the poly(2-methoxy,5-(2'ethylhexyloxy)-1,4-phenylene vinylene (MEH-PPV); and a statistical copolymer: the poly(2-methoxy, 5-(2'ethylhexyloxy)-co-2-methoxy, 5-(triethoxy-methoxy) -1,4-phenylene vinylene) (MEH-co-MTEM)-PPV. The analysis of PL spectra of PPV derivatives blended with salt or PEO-salt showed that PPVs with higher amount of ICSG present higher quenching effect on the PL efficiency in the presence of lithium salt complexes.