As the RAFT agents used are typically quite hydrophobic, an acetone transport technique was developed to assist the transport of the RAFT agent into the latex particles [1].

	start with a polystyrene seed latex (dead polymer)
	water is added (to final dilution of latex) acetone is added (20% w/w on total water) RAFT agent added (as crystals)
	mixture stirred for 24 to 72 hours acetone assists RAFT agent transport into latex particles; particles contain RAFT agent
	rotary evaporator used to strip acetone from latex (1.5 × mass of acetone removed) seed latex topped up with water
	monomer added to mixture with stirring particles swell over time, so there are no monomer droplets left seed now ready for use in reactions

References

1. Successful use of RAFT techniques in seeded emulsion polymerization of styrene: living character, RAFT agent transport and rate of polymerization. SW Prescott, MJ Ballard, E Rizzardo and RG Gilbert. Macromolecules, 35(14), 5417–5425, 2002.
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