Factors Affecting the Formation of the Monomer Sequence along Styrene/Methyl Methacrylate Gradient Copolymer Chains

The impact of the synthesis conditions on the formation of the monomer sequences of styrene (S) and methyl methacrylate (MMA) gradient copolymers synthesized by forced gradient copolymerization with nitroxide-mediated controlled radical polymerization (NM-CRP) was investigated using kinetic Monte Carlo (KMC) simulations The factors affecting the formation of the individual segments arrangement of these segments along the chain, and the uniformity of monomer sequences were investigated It was shown that instantaneous segment lengths increase exponentially as a function of segment lengths In addition, the arrangement of the segments mainly depends on the feed profile of the second monomer A constant feed profile, which is widely used in current syntheses of gradient copolymers, is shown to not be sutiable to make a structural gradient along the chain It was also demonstrated that the uniformity of sequence patterns can be affected by the entire growth history of the chains, and thus strong control over the uniformity of chain growth is required throughout the reaction in order to achieve sequences in different chains that resemble one another.