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The preparation of forced gradient polymers has received considerable attention using batch reactors, while the preparation of usable quantities of forced gradient copolymers using continuous flow reactors has been hampered by the need to vary the composition of the monomer feedstock continuously during the reaction. A reactor that allows for addition of a monomer feedstock continuously at all points along the length of the reactor tubing allows for the preparation of forced gradient copolymers in continuous flow reactors, allowing for the scale-up and bulk preparation of these polymers. This study reports here the initial investigation of preparing forced gradient copolymers using the reversible addition-fragmentation chain transfer methodology in tube-in-tube continuous flow reactors. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-pot sequential addition RAFT polymerization of quasi-block copolymers. • Very good polymer control achieved with high monomer conversions. • Light initiated chain extensions ease acrylate polymerization. • Monomer sequence has influence on thermal characteristics. • Phase morphology maintained in quasi-block copolymers. This works reports a novel approach at synthesising ionic quasi-block copolymers derived from a polystyrene- block -poly polyethylacrylate(butylimidazolium)bis(trifluromethanesulfonyl)imide block copolymer using a 'one-pot' RAFT polymerization technique. Three different quasi-block copolymer were synthesised following a sequential additional method whereby composition was altered through changing the order of monomer addition and the level of monomer conversion. The new quasi-block copolymers were analysed compositionally, thermally and through phase morphology to assess the impact this new synthesis has on polymer control and to determine whether block behaviour is maintained. The results suggests these new quasi-block behave similarly to block copolymers regarding phase behaviour, while offering potential for increased sustainability in the synthesis. [ABSTRACT FROM AUTHOR]

This work describes a multi-stage continuous flow polymerisation process for the synthesis of block copolymers using the RAFT polymerization method. The process retains all the benefits and versatility of the RAFT method and has been adapted for a series of monomer combinations, including acrylates, acrylamides, and vinyl monomers. It resulted in polymers with molecular weights between 13500 and 34100 g mol-1, and dispersities typically between 1.21 and 1.58. Different architectures were prepared (including combinations of hydrophilic and hydrophobic blocks) which are soluble in a range of different solvents including aqueous and organic media. The RAFT method allows polymer chains to be reinitiated and continue to grow, which makes it a very convenient and versatile technique for synthesising complex architectures, such as blocks or stars. We have developed a multi-stage continuous flow process for the RAFT polymerisation of a series of di-block copolymers, including combinations of hydrophilic and hydrophobic blocks. [ABSTRACT FROM AUTHOR]