Sequence-controlled methacrylic multiblock copolymers via sulfur-free RAFT emulsion polymerization

Abstract

Translating the precise monomer sequence control achieved in nature over macromolecular structure (for example, DNA) to whole synthetic systems has been limited due to the lack of efficient synthetic methodologies. So far, chemists have only been able to synthesize monomer sequence-controlled macromolecules by means of complex, time-consuming and iterative chemical strategies such as solid-state Merrifield-type approaches or molecularly dissolved solution-phase systems. Here, we report a rapid and quantitative synthesis of sequence-controlled multiblock polymers in discrete stable nanoscale compartments via an emulsion polymerization approach in which a vinyl-terminated macromolecule is used as an efficient chain-transfer agent. This approach is environmentally friendly, fully translatable to industry and thus represents a significant advance in the development of complex macromolecule synthesis, where a high level of molecular precision or monomer sequence control confers potential for molecular targeting, recognition and biocatalysis, as well as molecular information storage.

Synthesis and Applications of Protein/Peptide-Polymer Conjugates

“…Consequently, termination events can be minimized resulting in exceptional control over the molecular weight, molecular weight distribution (dispersity, Đ ) and chain‐end functionality up to quantitative conversions. Re‐initiation with sequential addition of alternative monomers can lead to the formation of multi‐block copolymers with complex compositions in which the side chain functionality is not perfectly, but discretely distributed throughout each polymer chain . The most recent advances in Cu‐mediated RDRP have centred on retaining this control over polymerisation in aqueous and biologically relevent media and using external stimuli to control the activation‐deactivation equilibrium (Figure ) …”

Controlling Nanomaterial Size and Shape for Biomedical Applications via Polymerization‐Induced Self‐Assembly

“…This approach was later termed PISA for the first time by Hashimoto and colleagues, and while only spherical particles were obtained in the first report by Ferguson et al., the technique has since been employed to prepare polymeric nanoparticles with various sizes and shapes . Due to the initial development focusing on potential industrial application, PISA via RAFT emulsion polymerization is not only scalable but is also friendly to the environment (no use of organic solvents) . That said, PISA did not attract wide interest when it was first reported, possibly due to the initial limitations in controlling particle size and shape.…”

Controlling the Polymer Microstructure in Anionic Polymerization by Compartmentalization

“…microfluidics,c opolymerization, controlled monomer addition, etc.). [12] Simultaneous copolymerization of two comonomers was used recently to prepare block copolymers [13] and sequence-controlled polymers [14] in radical emulsion polymerization, as emulsion templating reduces the number of radical side reactions. [6][7][8][9][10] Despite the development of living and controlled polymerization techniques in the last decades, [11] the use of competitive copolymerization to control monomer sequences was not well established;h owever, many complex macromolecular architectures are currently available by sequential or iterative protocols.…”