Synthesis and polymerisation of isotopically labelled methacrylate based monomers

Abstract

This thesis is concerned with the synthesis and polymerisation of isotopically labelled methacrylate based monomers. Chapter 2 describes the preparation of methyl [2-(^13)C]-and [3-(^13)C]-methacrylate via a Wittig-Homer type reaction and a diethyl malonate route respectively. The results of the free radical polymerisation of these monomers are discussed in Chapter 4. The presence of (^13)C-isotope in the resultant polymer enhanced the low intensity signals from the end groups in the (^13)C-NMR. However, more importantly, this study allowed us to investigate the presence of head to head links by observing for the first order (^13)C-(^13)C coupling from the two quaternary carbons in the polymer of methyl [2-(^13)C]- methacrylate. The findings of this study are reported in Chapter 4, Part 1.Chapter 3 describes the preparation of methyl [a-(^13)C]-(hydroxymethyl)-[3-(^13)C]-acrylate, [(^13)C(_2)]-MHMA and methyl [a-(^2)H(^2)-(hydroxymethyl).[3-(^13)C]-acrylate, [(^2)H(_4)]- MHMA monomers. The copolymeristion with methyl methacrylate and subsequent lactonisation are reported in Chapter 4, Part 2. In the (^13)C-NMR spectrum of lactonised MMA/[(^13)C(_2)]-MHMA copolymer, the signals from any residual (^13)CH(_2)OH groups were absent, indicating that lactonisation was complete under the conditions described. Chapter 5 describes the preparation of fluorinated and non-fluorinated phosphonate based methacrylate monomers to study their potential as ionic materials and extend their application as a fire retarding material. However, attempts to polymerise these monomers by either free radical or anionic methods met with little success. The successful preparation of a polymer from a non-phosphonate based methacrylate monomer indicates that perhaps the phosphonate moiety inhibits the polymerisation by being a radical acceptor.