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Synthesis of Poly(propylene oxide)-Poly(N,N'-dimethylacrylamide) Diblock Copolymer Nanoparticles via Reverse Sequence Polymerization-Induced Self-Assembly in Aqueous Solution.

ABSTRACT: Sterically-stabilized diblock copolymer nanoparticles comprising poly(propylene oxide) (PPO) cores are prepared via reverse sequence polymerization-induced self-assembly (PISA) in aqueous solution. N,N'-Dimethylacrylamide (DMAC) acts as a cosolvent for the weakly hydrophobic trithiocarbonate-capped PPO precursor. Reversible addition-fragmentation chain transfer (RAFT) polymerization of DMAC is initially conducted at 80% w/w solids with deoxygenated water. At 30-60% DMAC conversion, the reaction mixture is diluted to 5-25% w/w solids. The PPO chains become less solvated as the DMAC monomer is consumed, which drives in situ self-assembly to form aqueous dispersions of PPO-core nanoparticles of 120-190 nm diameter at 20 °C. Such RAFT polymerizations are well-controlled (M_w/M_n ≤ 1.31), and more than 99% DMAC conversion is achieved. The resulting nanoparticles exhibit thermoresponsive character: dynamic light scattering and transmission electron microscopy studies indicate the formation of more compact spherical nanoparticles of approximately 33 nm diameter on heating to 70 °C. Furthermore, 15-25% w/w aqueous dispersions of such nanoparticles formed micellar gels that undergo thermoreversible (de)gelation on cooling to 5 °C.

SUBMITTER: Farmer MAH

PROVIDER: S-EPMC10782481 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Synthesis of Poly(propylene oxide)-Poly(<i>N,N'</i>-dimethylacrylamide) Diblock Copolymer Nanoparticles via Reverse Sequence Polymerization-Induced Self-Assembly in Aqueous Solution.

Farmer Matthew A H MAH Musa Osama M OM Haug Iris I Naumann Stefan S Armes Steven P SP

Macromolecules 20231217 1

Sterically-stabilized diblock copolymer nanoparticles comprising poly(propylene oxide) (PPO) cores are prepared via reverse sequence polymerization-induced self-assembly (PISA) in aqueous solution. <i>N,N</i>'-Dimethylacrylamide (DMAC) acts as a cosolvent for the weakly hydrophobic trithiocarbonate-capped PPO precursor. Reversible addition-fragmentation chain transfer (RAFT) polymerization of DMAC is initially conducted at 80% w/w solids with deoxygenated water. At 30-60% DMAC conversion, the re ...[more]

PMID: 38222027

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Dataset Information

Synthesis of Poly(propylene oxide)-Poly(N,N'-dimethylacrylamide) Diblock Copolymer Nanoparticles via Reverse Sequence Polymerization-Induced Self-Assembly in Aqueous Solution.

Publications

Synthesis of Poly(propylene oxide)-Poly(<i>N,N'</i>-dimethylacrylamide) Diblock Copolymer Nanoparticles via Reverse Sequence Polymerization-Induced Self-Assembly in Aqueous Solution.

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