The photoluminescence behaviors of poly(2-methyoxy-5-(2′-ethylhexyloxy)-1

4-phenylenevinylene) (MEH-PPV)/organoclay (OMMT) nanocompsites in both solvent and solid were investigated in this paper.The results demonstrated that nano-layered silicates may enhance the luminescent performance of MEH-PPV primarily based on structural and conformational modulation.The appearance of OMMT could induce more J aggregates other than H aggregates of MEH-PPV

which result in a red-shift of the emission and higher electroluminescence efficiency.To understand the mechanism of the luminescent enhancement for the nanocomposites

the measurements of steady fluorescence emission

fluorescence lifetime (τ) and spin-lattice relaxation time (t1) of the individual carbon atoms in MEH-PPV for the nanocomposite films were carried out.It is obviously that with increasing OMMT content in the nanocomposites

the Stokes shift together with the fluorescence lifetime showed a prolonging tendency

and the t1 of the conjugated carbon atoms in MEH-PPV backbone shortened linearly.All of the results indicated that

with the increase of OMMT content

the interchain interaction and π-π* transition decreased

the proportion of J-aggregation and the mobility of the conjugated segments increased.Consequentially

both the self-aggregation of the polymer chains and the self-quenching of luminescent emission reduced.