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Zeolites NaY and ZSM-5 were used as hosts for styrene polymerization after ion-exchange with europium ions. The parent and hybrid, polystyrene coated Eu-NaY (Eu-NaY/PS) and Eu-ZSM-5 (Eu-ZSM-5/PS) zeolites were investigated by using thermal analysis, SEM, PXRD, FT-IR, DR-UV/Vis, steady state and time-resolved photoluminescence spectroscopy. FT-IR spectra evidenced for the interaction between the zeolitic hosts and polystyrene while the PXRD spectra supported for the presence of the polymer inside the channels/pores of Eu-NaY/PS and Eu-ZSM-5/PS materials. The optical properties of Eu-NaY/PS and Eu-ZSM-5/PS were significantly changed relative to those of the parent zeolites, giving further evidence for the presence of polymer inside zeolites. An interesting case is presented by NaY zeolite: following styrene polymerization, the polymer interacted selectively with one of the two main species co-existing inside zeolite while for ZSM-5 a similar effect was not observed.
A series of terbium- and europium-exchanged microporous-mesoporous zeolite Socony Mobil Five (MFI)-type materials such as Zeotile-1 and Zeogrid with varying Si/Al ratios was investigated using FTIR, PXRD, adsorption- desorption isotherms of N-2 at 77 K and time-resolved luminescence spectroscopy. Silylation of the lanthanides-exchanged Zeotile-1 and Zeogrid with hexadecyl trimethoxysilanes via post-synthesis grafting was also studied. The results showed that the lanthanide's photoluminescence spectra and decays were modified due to silylation. The different silylation effects in Zeotile-1 and Zeogrid were correlated with the textural properties of the investigated materials. (C) 2007 Elsevier B.V. All rights reserved.