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PP-III-22TAILORING POLYMER PRODUCTS VIA LIVING POLYMERIZATIONGomes V.G.School of Chemical and Biomolecular Engineering, University of Sydney,NSW 2006, Australia, vincent.gomes@sydney.edu.auINTRODUCTIONAccurate control of product properties can be of great benefit to industry in producingtargeted polymeric materials. Living polymerization via free radical mechanism (LFRP)provides opportunities to control polymer architecture and molar mass distribution, whichare fundamental attributes of polymer materials. Block copolymers synthesized by LFRPoffer the potential of tuning product properties precisely. Thus, chemically controlledliving free radical polymerisation was tested with reversible addition–fragmentation chaintransfer (RAFT), a most promising technique for industry [1-3] . RAFT is facilitated bycompounds having structures such as Z-C(=S)S-R. During its pre-equilibrium stage, theaddition of the initiator-derived propagating radical Pn *to thiocarbonylthio reagentfollowed by forward fragmentation of the carbon centred intermediate radical gives riseto a polymeric RAFT moiety and a new radical R * . The process is followed by forwardfragmentation of the intermediate radical giving rise to a polymeric RAFT agent and anew reinitiating radical, which reacts to produce a new propagating radical and extendsthe polymeric chain.MODELLINGOur RAFT emulsion polymerization model accounts for reactions in the aqueousand particle phases during propagation, termination, transfer to monomer and RAFTexchange, along with radical absorption and desorption to and from particles. A‘zero-one’ model was developed based on the consideration that the rate of radicalradicaltermination within a particle is fast relative to the rate of radical entry intoparticles. Thus a particle has either zero or one radical. Our model equations for themulti-phase system include governing equations for the aqueous phase, the organicliquid phase, the particle phase with the species balances and the energy balanceover the reactor and the heating/cooling system. The mixed differential and integropartialdifferential equations were solved using our developed software. The modelpredictions for a range of operational conditions were compared with ourexperimental results.480