Possibilities and Limitations of Cationic Polymerisation in the Presence of Water

Résumé

In this thesis, the possibilities and limitations of conducting cationic polymerisation of vinylic monomers in the presence of water are explored. Revisiting a large amount of work in the literature has shown that previous reports of cationic polymerisations in aqueous media leading to high molecular weights actually proceed via a radical mechanism. Based on theoretical arguments backed up by experimental data, it is shown that cationic polymerisation in water is in fact limited to the synthesis of low molecular weight polymers due to a combination of intrinsic chain transfer reactions that occur at ambient temperature and reactions with water. Following these results, the use of water-tolerant catalyst systems in wet solution is explored. The synthesis of low molecular weight poly(ß-pinene) to be used as tackifiers in the formulation of pressure-sensitive adhesives as well as the controlled polymerisation of polystyrene and poly(p-methoxystyrene) using reversible addition-fragmentation chain transfer cationic polymerisation under mild conditions is studied.