Telechelic polymers, polymers with two reactive end-groups, are sought after for their role in synthesizing macromolecules with complex structures such as multiblock copolymers and graft polymers. Many strategies for the synthesis of telechelic polymers from vinyl monomers using controlled radical polymerizations and anionic polymerizations exist. However, polyolefins—which account for the major fraction of polymer production—are not easily synthesized with two reactive end-groups. This difficulty is related to the sensitivity of olefin polymerization catalysts and their propensity for intramolecular chain transfer reactions. As a result, the most common strategies to access telechelic polyethylene and polypropylene (the two major polyolefins) do not rely on the insertion polymerization of ethylene nor propylene but rather on the polymerization of dienes or cyclic olefins. Nonetheless, recent advances in insertion polymerization and post-polymerization functionalization have resulted in the emergence of novel synthetic methods to access telechelic polyolefins. We here present a comprehensive review of all of these strategies to synthesize telechelic polyolefins.
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Development of Multifunctional Cathode Binder via Inverse Vulcanization for Lithium–Sulfur Battery with Enhanced Capacity Retention
Vinyl-benzaldehyde (VB) monomers containing four functional groups were newly synthesized using the Williamson ether synthesis method. The two aldehyde groups of the synthesized monomers were able to react with amine-terminated macromonomers to form flexible networks. In addition, the two vinyl groups were found to be capable of inverse vulcanization with sulfur by conducting qualitative chemical analysis. The lithium−sulfur battery prepared using the VB-based cathode binder achieved high specific capacity with excellent capacity retention compared to conventional sulfur batteries, demonstrating the potential of the new binder.
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- Award ID(s):
- 2214006
- PAR ID:
- 10518149
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry C
- Volume:
- 127
- Issue:
- 25
- ISSN:
- 1932-7447
- Page Range / eLocation ID:
- 11836 to 11844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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