Complex polymer architectures through free-radical polymerization of multivinyl monomers

The construction of complex polymer architectures with well-defined topology, composition and functionality has been extensively explored as the molecular basis for the development of modern polymer materials. The unique reaction kinetics of free-radical polymerization leads to the concurrent formation of crosslinks between polymer chains and rings within an individual chain and, thus, free-radical (co)polymerization of multivinyl monomers provides a facile method to manipulate chain topology and functionality. Regulating the relative contribution of these intermolecular and intramolecular chain-propagation reactions is the key to the construction of architecturally complex polymers. This can be achieved through the design of new monomers or by spatially or kinetically controlling crosslinking reactions. These mechanisms enable the synthesis of various polymer architectures, including linear, cyclized, branched and star polymer chains, as well as crosslinked networks. In this Review, we highlight some of the contemporary experimental strategies to prepare complex polymer architectures using radical polymerization of multivinyl monomers. We also examine the recent development of characterization techniques for sub-chain connections in such complex macromolecules. Finally, we discuss how these crosslinking reactions have been engineered to generate advanced polymer materials for use in a variety of biomedical applications.

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Acknowledgements

The authors acknowledge the Science Foundation Ireland (SFI) Principal Investigator (PI) Programme (13/IA/1962) (to W.W.), National Science Foundation (NSF) Division of Materials Research (DMR) (1501324) (to K.M.), National Natural Science Foundation of China (NSFC) (51873179) (to W.W.), Senior Visiting Scholarship of State Key Laboratory of Molecular Engineering of Polymers, Fudan University (19FGJ07) (to W.W.), Irish Research Council (IRC) Employment-Based Postgraduate Programme (EBPPG/2018/159) (to J.L.) and University College Dublin (to Y.G.) for financial support. The authors apologize to those whose work is relevant but could not be cited owing to space limitations.

Author information

  1. Yongsheng Gao Present address: School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA

Authors and Affiliations

  1. Charles Institute of Dermatology, School of Medicine, University College Dublin, Dublin, Ireland Yongsheng Gao, Dezhong Zhou, Jing Lyu, Sigen A, Qian Xu & Wenxin Wang
  2. School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi, China Dezhong Zhou
  3. School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland Jing Lyu & Wenxin Wang
  4. School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK Ben Newland
  5. Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, USA Krzysztof Matyjaszewski
  6. School of Chemistry, Bangor University, Deiniol Road, Bangor, Gwynedd, UK Hongyun Tai
  7. State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, China Wenxin Wang
  1. Yongsheng Gao