The RAFT polymerization of styrene in a solvent consisting of a water/alcohol mixture with different water contents is performed and the solvent effects on polymerization kinetics, polymer chain propagation, and polymer particle growth are evaluated. It is found that the solvent affects the RAFT polymerization kinetics greatly, and the apparent polymerization rate constant (K_p ^app) increases with an increase in the water content of the water/alcohol mixture. In addition, RAFT polymerization in a water/alcohol mixture with a higher water content affords better control of the polydispersity index (PDI) of the synthesized polymers. Furthermore, the solvent also exerts a great influence on the growth of the polymer particles. Hollow particles are formed either at the initial polymerization with low monomer conversion or in the solvent with a low water content, whereas solid polymer particles are produced either at high monomer conversion or in the solvent with a high water content.

onlinelibrary.wiley.com/doi/10.1002/macp.201200640/abstract