Tailoring Uniform Copolymer Composition Distribution via Policy II RAFT Solution Copolymerization of Styrene and Butyl Acrylate

摘要

Controlled radical polymerization (CRP) is regarded as a powerful method to design various chain structures. Semibatch monomer feeding strategies in CRP are widely used for targeting the polymer products with desired copolymer composition distribution (CCD) and molecular weight distribution, which define the properties of polymer materials. In this work, the uniform CCD in reversible addition-fragmentation transfer (RAFT) solution copolymerization is targeted via model-based semibatch Policy II. A RAFT solution copolymerization model is first developed and correlated with batch styrene (St) and butyl acrylate (BA) copolymerization experimental data. St/BA copolymers having three different uniform compositions are produced by the comonomer feeding Policy II. Heat and concentration analysis prove feasibility of the policy. Simulation results show that the uniform CCD can be achieved by both Policy II and Policy I, compared with starved feeding and constant feeding. Policy II gives higher and more steady rates than Policy I.