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The choice of chain transfer agent in reversible addition/fragmentation chain transfer polymerization has proven to be instrumental in modulating the dispersity of a certain polyphenyl vinyl ketone (PVK). The monomer, PVK, which can self-initiate when exposed to blue light, was used to synthesize homopolymers, block copolymers by extending with a different monomer and gradient polymers. Regardless of the polymer architecture or degree of polymerization, a consistent trend in polymer dispersity was quantified, with higher loadings of the less active chain transfer agent xanthate leading to higher dispersities. The dispersity could be further modulated by photodegradation of vinyl ketone polymers under UV irradiation.
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Redefining the Limits: Atom Transfer Radical Polymerization of Vinyl Ketone Monomers under Light
Vinyl ketone polymers, including poly(phenyl vinyl ketone) and poly(p-chlorophenyl vinyl ketone) were successfully synthesized under light using atom transfer radical polymerization (ATRP). This marks the first successful attempt at ATRP of vinyl ketones. The polymerization kinetics revealed chain growth and maintained livingness, as further evidenced by successful chain extension using ethyl acrylate. The efficient main-chain cleavability of the polymers was confirmed under UV light. While the attainment of low dispersity remains an enduring challenge, this work offers promising potential for future success.
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- Award ID(s):
- 2203727
- PAR ID:
- 10661299
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Macro Letters
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2161-1653
- Page Range / eLocation ID:
- 231 to 236
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acsmacrolett.5c00781
