RAFT-mediated, visible light-initiated single unit monomer insertion and its application in the synthesis of sequence-defined polymers

Author(s): Changkui Fu ¹ ^, ² ^, ³ ^, ⁴ ^, ⁵ , Zixuan Huang ¹ ^, ² ^, ³ ^, ⁴ ^, ⁵ , Craig J. Hawker ⁶ ^, ⁷ ^, ⁸ ^, ⁹ ^, ¹⁰ , Graeme Moad ¹¹ ^, ¹² ^, ⁵ , Jiangtao Xu ¹ ^, ² ^, ³ ^, ⁴ ^, ⁵ , Cyrille Boyer ¹ ^, ² ^, ³ ^, ⁴ ^, ⁵

Publication date (Electronic): 2017

Journal: Polymer Chemistry

Publisher: Royal Society of Chemistry (RSC)

Read this article at

ScienceOpenPublisher

Bookmark

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

In this communication, we report a catalyst-free methodology for single unit monomer insertion (SUMI) into reversible addition–fragmentation chain transfer (RAFT) agents initiated by low intensity visible light. This method is applicable to broad range of monomer families (monosubstituted vinyl monomers) and allows for the preparation of the corresponding single monomer insertion product in high yields (typically >90%; isolated yields after chromatography 60–80%). The fidelity of the end-functional SUMI products is demonstrated with use of the SUMI products in RAFT polymerization and by using the tools of conventional chemistry (thiol–ene and esterification reactions). A uniform oligomer comprising five discrete vinyl monomer repeat units was synthesized by an iterative strategy comprising three consecutive SUMI reactions and two intermediate esterification and thiol–ene steps. We thus demonstrate a new protocol for incorporating the rich functionality of available vinyl monomers into polymers where sequence is precisely defined at the monomer level.

Related collections

Most cited references 55

Record: found
Abstract: found
Article: not found

Thiol-click chemistry: a multifaceted toolbox for small molecule and polymer synthesis.

Charles Hoyle, Andrew Lowe, Christopher Bowman (2010)

The merits of thiol-click chemistry and its potential for making new forays into chemical synthesis and materials applications are described. Since thiols react to high yields under benign conditions with a vast range of chemical species, their utility extends to a large number of applications in the chemical, biological, physical, materials and engineering fields. This critical review provides insight into emerging venues for application as well as new mechanistic understanding of this exceptional chemistry in its many forms (81 references).

0 comments Cited 301 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

A robust and versatile photoinduced living polymerization of conjugated and unconjugated monomers and its oxygen tolerance.

Jiangtao Xu, Kenward Jung, Amir Atme … (2014)

Controlled/living radical polymerization techniques have transformed polymer chemistry in the last few decades, affording the production of polymers with precise control over both molecular weights and architectures. It is now possible to synthesize almost an infinite variety of macromolecules using nonspecialized equipment, finding applications in high-tech industry. However, they have several shortcomings. Until recently, living radical polymerizations could not be controlled by an external stimulus, such as visible light, pH, mechanical, chemical, etc. Moreover, they are usually sensitive to trace amounts of oxygen in the system. In this Article, we report a photoinduced living polymerization technique, which is able to polymerize a large range of monomers, including conjugated and unconjugated monomers, using ultralow concentrations of an iridium-based photoredox catalyst (typically 1 ppm to monomers) and a low energy visible LED as the light source (1-4.8 W, λ(max) = 435 nm). The synthesis of homopolymers with molecular weights ranging from 1000 to 2,000,000 g/mol was successfully achieved with narrow molecular weight distributions (M(w)/M(n) < 1.3). In addition, chain extensions of poly(methacrylate)s, poly(styrene), poly(N-vinyl pyrrolidinone), poly(vinyl ester)s, and poly(acrylate)s were performed to prepare diblock copolymers. The reusability of the catalyst was demonstrated by the synthesis of a decablock polymer by multiple chain extensions. Most importantly, this process was employed to prepare well-defined polymers and multiblock copolymers in the presence of air.