Block and multi block copolymers via SF-RAFT : utilising macromonomers as chain transfer agents

• Main Author: Engelis, Nikolaos
• Published: University of Warwick 2018
• Subjects: 540; QD Chemistry
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759707

The objective of this work is to investigate and expand the use of methacrylic macromonomers as chain transfer agents. Although chain transfer activity had been demonstrated previously, the limits of the technique have not been fully explored. As such, a new approach for the efficient synthesis of methacrylic polymers in emulsion is presented, aiming at fully exploiting the vinyl end-group of the CCTP-derived macromonomers and consequently their chain transfer activity. Moreover, the preparation of higher MWt copolymers as well as more complex structures (e.g. triblocks etc) by this method will be investigated as research so far has only been focusing on certain degrees of polymerisation, mainly resulting in diblock copolymers of relatively low MWt. In addition, macromonomers based on diverse methacrylic monomers will be employed, as most studies to date have focused on a narrow monomer pool. In parallel, another aspect of radical polymerisation in the presence of macromonomers is the livingness of the system. Even though living-like characteristics have been observed, previous studies did not reach definitive conclusions, according to the generally set criteria of livingness. At the same time, the use of macromonomers as precursors for comb-like polymers will be described. Despite the technique being known and well-reported, the aim is to successfully employ solvents that satisfy the needs of automotive applications, such as mineral oil. In detail, both the macromonomer synthesis and the subsequent comb formation will be attempted in this solvent. A similar approach has not been reported so far. It needs to be noted, that this part is an ongoing work with the Lubrizol Corporation and as such it only demonstrates a few initial steps towards developing materials with interesting properties and applications.