The effect of pressure on the luminescence of poly[2-methoxy-5-(2′-ethyl hexoxy)–p-phenylene vinylene] [MEH–PPV] in two copolymers of vinylchloride

The change of emission efficiency with pressure is presented for poly[2-methoxy-5-(2′-ethylhexoxy)–p-phenylene vinylene] (MEH–PPV) in dilute solution in poly(vinyl chloride) (PVCl), poly(vinyl acetate) (PVA) and two copolymers involving VCl. The drop in efficiency below 30 kbar in all media correlates with the increase in time of transport of the electron from the exciting to the emitting state. The increase in luminescent yield above 30 kbar for PVCl and the copolymers correlates with the increase in Förster energy transfer (FET) efficiency. For PVA there is no increase in FET at higher pressure and no increase in luminescent efficiency.