Kinetic Modeling of the Synthesis of Poly(4-vinylpyridine) Macro-Reversible Addition-Fragmentation Chain Transfer Agents for the Preparation of Block Copolymers

Reversible addition-fragmentation chain transfer (RAFT)polymerizationis one of the most common controlled polymerization techniques toprepare well-defined, rather narrow dispersed polymers due to reduceddemands in reactant preparation. Despite these advantages, RAFT polymerizationwas so far primarily utilized on small laboratory scales. This studypresents a first step to a scaled-up RAFT polymerization by developingand experimentally validating a kinetic model on the example of thepolymerization of 4-vinylpyridine (4VP), which to date is not describedin the literature. With the implementation of the results from modeling,the synthesis process was extended to a medium scale (from 6 to 36g), while the same high conversions, molar mass, and low dispersityas in the smaller scale were achieved. The process is also optimizedregarding the high degree of livingness necessary for using the 4VPpolymers as a macro-RAFT agent in the subsequent reaction step forthe synthesis of poly-(4-vinylpyridine)-b-polystyrenediblock copolymers by RAFT dispersion polymerization.