Self-assembly of hydrophilic homopolymers : a matter of RAFT end groups
Du, Jianzhong, Willcock, Helen, Patterson, Joseph P., Portman, Ian J. and O'Reilly, Rachel K.. (2011) Self-assembly of hydrophilic homopolymers : a matter of RAFT end groups. Small, Vol.7 (No.14). pp. 2070-2080. ISSN 1613-6810Full text not available from this repository.
Official URL: http://dx.doi.org/10.1002/smll.201100382
Unusual self-assembly behavior is observed for a range of hydrophilic homopolymers. This self-assembly behavior is contrary to the expected behavior of such hydrophilic polymers and instead mimics more commonly reported amphiphilic block copolymers. It is proposed that the unique combination of hydrophobic end groups at both the alpha and omega chain end accounts for this unusual self-assembly behavior. Complex internal polymer micelles are spontaneously formed when hydrophilic homopolymer polyelectrolytes and neutral polymers (with a weight fraction of the hydrophobic end groups <10 wt%) are directly dissolved in water. The homopolymers, poly[2-(diethylamino)ethyl methacrylate], poly(N-isopropylacrylamide), and poly(ethoxyethylacrylate) are synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization using S'-1-dodecyl-(S')-(alpha,alpha'-dimethyl-alpha ''-acetic acid) trithiocarbonate (DDMAT) and its derivatives as chain transfer agents (CTAs). A range of polyelectrolyte homopolymers with different terminal groups are designed and synthesized, which under acidic aqueous solution direct the self-assembly to form well-defined nanostructures. This assembly behavior was also observed for neutral polymers, and it was determined that the structure of the hydrophobic end groups (and thus choice of RAFT CTA) are very important in facilitating this unusual self-assembly behavior of hydrophilic homopolymers. It is proposed that the functionality of commonly used CTAs such as DDMAT, can affect the solution association of the resultant homopolymers and can in fact afford ABA' type polymers, which can undergo self-assembly to form higher-order nanostructures.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry|
|Divisions:||Faculty of Science > Chemistry|
|Library of Congress Subject Headings (LCSH):||Polymerization, Water-soluble polymers, Block copolymers, Diblock copolymers, Self-assembly (Chemistry)|
|Journal or Publication Title:||Small|
|Publisher:||Wiley - V C H Verlag GmbH & Co. KGaA|
|Date:||18 July 2011|
|Page Range:||pp. 2070-2080|
|Access rights to Published version:||Restricted or Subscription Access|
|Funder:||Engineering and Physical Sciences Research Council (EPSRC), Leverhulme Trust (LT), Royal Society (Great Britain)|
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