Auteur / Autrice : | Fanny Bonnet |
Direction : | Denise Barbier-Baudry, Marc Visseaux |
Type : | Thèse de doctorat |
Discipline(s) : | Chimie - Physique |
Date : | Soutenance en 2003 |
Etablissement(s) : | Dijon |
Mots clés
Mots clés contrôlés
Résumé
With an ansa samarocene complex it was possible to synthesis copolymers of dienes with a-olefines of various lengths. We studied the influence of the chain length of the olefin inserted on the physical-chemical properties. Functional copolymers were also obatined by the use of a,w-dienes as comonomers (octa-1,7-diene, hexa-1,5-diene), and by the insertion of only one double bond in the polydiene chain. With the same complex we were able to elaborate block copolymers of dienes with polar monomers (e-caprolactone, methyl methacrylate), and we have shown that these copolymers were efficient compatibilisers in polar and non polar polymer blends. A new family of rare earth hemimetallocene complexes was then developped. Samarium and Neodymium complexes were synthesised by the use of chloride and borohydride precursors, with a cyclopentadienyl ligand close to the permethylcyclopentadienyl one (Cp*'), with the general formula Cp*'Ln X2 (THF)n, X=BH4, Cl. By substitution of one X ligand by a diiminate one (NN), we could isolate genuine heteroleptic complexes Cp*'Ln X (NN). These new complexes, in the presence of MgR2 as co-activator, are efficient catalysts for the polymerisation of dienes with a trans specificity up to 98. 9% in the case of the borohydride ones, this result gives some outlooks for the copolymerisation with olefins.