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Abstract An orthogonal combination of cationic and radical RAFT polymerizations is used to synthesize bottlebrush polymers using two distinct RAFT agents. Selective consumption of the first RAFT agent is used to control the cationic RAFT polymerization of a vinyl ether monomer bearing a secondary dormant RAFT agent, which subsequently allows side‐chain polymers to be grafted from the pendant RAFT agent by a radical‐mediated RAFT polymerization of a different monomer, thus completing the synthesis of bottlebrush polymers. The high efficiency and selectivity of the cationic and radical RAFT polymerizations allow both polymerizations to be conducted in one‐pot tandem without intermediate purification.
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Alcohol mediated degenerate chain transfer controlled cationic polymerisation of para -alkoxystyrene
In this report we demonstrate methanol as an effective degenerative chain transfer agent to control the cationic polymerisation (initiated by triflic acid) of electron rich p -alkoxy-styrenes, such as p -methoxystyrene ( p -MOS). Kinetic analysis revealed that an induction period occurs initially during which free cationic polymerisation occurs at low monomer conversion before proceeding through the pseudo first order rate, analogous to the RAFT mechanism. Ethanol and isopropanol also demonstrated excellent control ( Đ > 1.30), however, with an apparent increase in experimental molecular weight. Furthermore, methanol controlled polymers were successfully chain extended upon sequential monomer addition, demonstrating the ‘livingness’ of the alcohol mediated cationic polymerisation.
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- Award ID(s):
- 1808055
- PAR ID:
- 10107234
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 10
- Issue:
- 30
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 4126 to 4133
- 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/10.1039/c9py00480g
