The preparation and spectral characterisation of vinylferrocene-styrene copolymer latexes

A series of vinylferrocene-styrene copolymer latexes having different vinyl ferrocene to styrene ratios were prepared via a free radical mechanism. The oretical DLVO calculations have been used to model the aggregation behaviou r of the polymer latexes with respect to a change in particle zeta potentia l. It has been shown that a critical value of the zeta potential of approxi mately - 25 mV is necessary to confer latex stability. The Mossbauer spectr a of the copolymers at 78 K showed the doublet characteristic of that expec ted for ferrocene and vinylferrocene monomer. The spectra also revealed tha t a second iron site was present. The Mossbauer parameters were consistent with oxidation having occurred yielding the ferrocenium ion. At room temper ature, however. there was little evidence of the spectrum due to ferrocene. The major spectral feature had parameters similar to those for the ferroce nium site observed at the lower temperatures. The values obtained in this s tudy are compared with those previously reported for other ferrocene-contai ning polymers, which were explained in terms of a cross-linked structure in the polymer consisting of two ferrocene units. (C) 2001 Elsevier Science B .V. All rights reserved.