RAFT Miniemulsion Polymerization Kinetics, 2 – Molecular Weight Distribution

The molecular weight distribution formed in a RAFT polymerization conducted inside submicron particles ( D p < 300 nm) is considered. For small particles, the MWD at low to middle conversion might be rather broad because of the large differences in MWDs formed in different polymer particles. Such a broad MWD can be made narrower by increasing the radical entry frequency. On the other hand, larger frequencies of radical entry result in a broader MWD at the final conversion levels. The number of dead polymer chains increases with time, and the dead polymer peak could be observed in the MWD at a prolonged aging time. According to this theoretical investigation, smaller particles are advantageous in implementing a faster polymerization rate, a narrower MWD, and a smaller number of dead polymer molecules. magnified image