Dynamic behavior of pyrene fluorescence in highly oriented polymer LB films

The photophysical properties of the pyrene chromophore in poly(tert-pentylacrylamide-co-1-pyrenylmethyl acrylate) (p(tPA/PyMA)) Langmuir–Blodgett (LB) monolayer were studied. It is found that the emission property of the pyrene is drastically changed by capping with polymer LB films. When the pyrene monolayer was capped with poly(N-dodecylacrylamide) (p(DDA)) LB films, the emission intensity ratio of the excimer to the monomer (IEx/IMon) was increased with increasing temperature, whereas the IEx/IMon value was decreased with increasing temperature in the capping with poly(tert-pentylacrylamide) (p(tPA)) LB film. This interesting effect is discussed on the basis of the time-resolved emission spectroscopy.