Cross linking-dependent properties of PVK-MEH-PPV bi-block copolymer: Vibrational, thermal and optical properties

Despite its interesting optoelectronic properties, the insolubility of poly (N-vinylcarbazole-poly [2-methoxy-5-2 (ethylhexyloxy)-1,4-phenylenevinylene] (PVK-MEH-PPV) bi-block copolymer has caused some difficulties especially for the elaboration of new composites based on this copolymer and [6,6]-phenyl-C61-butanoate of methyl (PCBM). To solve the problem of insolubility, we first modify quantitatively a main parameter in the chemical synthesis, namely the oxidant agent and then replaced with a new one. Dramatic changes in the vibrational and optical properties are founded by varying the FeCl3 amount in the synthesis way due to the cross-linking of PVK units. This is induces the modulation of copolymers properties particularly theirs emissive proprieties due to the modulation of PVK and MEH-PPV contribution. A red shifting of the maximum of photoluminescence and a quenching was observed with increasing of the oxidation yields. Composite based PCBM and copolymer was elaborated due the solubility of one of copolymer by changing the oxidant agent.