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Abstract Chemically recyclable polymers offer a promising solution to address the issues associated with the unsustainable use of plastics by converting the traditional linear plastic economy into a circular one. Central to developing chemically recyclable polymers is to identify the appropriate monomers that enable practical conditions for polymerization and depolymerization and ensure useful stability and material properties. Our group has recently demonstrated thattrans‐cyclobutane‐fused cyclooctene (tCBCO) meets the abovementioned requirements and is a promising candidate for developing chemically recyclable polymers. Herein, encouraged by the success withtCBCO, we investigate the thermodynamics of polymerization of a relevant system,trans‐benzocyclobutene‐fused‐cyclooctene, which can be viewed astCBCO with an additional benzene ring. The study shows that introducing an additional benzene ring favors polymerization and disfavors depolymerization, and the effect is predominantly entropic. The benzo‐effect can be leveraged to fine‐tune the thermodynamics of polymerization and depolymerization to facilitate the chemical recycling of polymers.
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Regulating cationic polymerization: From structural control to life cycle management
Cationic polymerization is a powerful strategy for the production of well-defined polymers and advanced materials. In particular, the emergence of living cationic polymerization has enabled pathways to complex polymer architectures inaccessible before. The use of light and electricity as external stimuli to regulate cationic polymerization represents another advance with increasing applications in surface fabrication and patterning, additive manufacturing, and other advanced material engineering. The past decade also witnessed vigorous progress in stereoselective cationic polymerizations, allowing for the dual control of both the tacticity and the molecular weight of vinyl polymers towards precision polymers. In addition, in addressing the plastics pollution crisis and achieving a circular materials economy, cationic polymerization offers unique advantages for generating chemically recyclable polymers, such as polyacetals, polysaccharides, polyvinyl ethers, and polyethers. In this review, we provide an overview of recent developments in regulating cationic polymerization, including emerging control systems, spatiotemporally controlled polymerization (light and electricity), stereoselective polymerization, and chemically recyclable/degradable polymers. Hopefully, these discussions will help to stimulate new ideas for the further development of cationic polymerization for researchers in the field of polymer science and beyond.
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- Award ID(s):
- 1944512
- PAR ID:
- 10497351
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Progress in Polymer Science
- Volume:
- 145
- Issue:
- C
- ISSN:
- 0079-6700
- Page Range / eLocation ID:
- 101736
- Subject(s) / Keyword(s):
- Living polymerization Organocatalysis Photocontrolled polymerization Electrocontrolled polymerization Stereoselective polymerization Sustainable materials
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.progpolymsci.2023.101736
