Surfactant-free RAFT-mediated Emulsion Polymerisation

摘要

There is an increasing number of articles being published describing the use of hydrophilic macro-RAFT agents in surfactant-free emulsion polymerisation. This technique is particularly effective at producing self-stabilised latex particles with controlled polymer MW and morphology. The present article represents a further contribution to this field of study, whereby a poly[sodium styrene sulphonate (NaStS)]-RAFT macromer was used as sole stabiliser in the emulsion polymerisation of St. Initially three macro-RAFT agents, differing in MW were prepared by the solution polymerisation of NaStS using 4-cyanopentanoic acid dithiobenzoate as RAFT agent. By varying RAFT agent and initiator concentrations, macro-RAFT agents with approximate number-average MWs of 1200, 47000 and 116000 were prepared. These were then employed at a level of lwt% of monomer in the batch emulsion polymerisation of St.