Redox-Initiated Reversible Addition-Fragmentation Chain Transfer (RAFT) Miniemulsion Polymerization of Styrene using PPEGMA-Based Macro-RAFT Agent.
Macromol Rapid Commun
; 41(20): e2000399, 2020 Oct.
Article
em En
| MEDLINE
| ID: mdl-32902024
ABSTRACT
Redox-initiated reversible addition-fragmentation chain transfer (RAFT) miniemulsion polymerizations are successfully conducted with an employment of trithiocarbonate-based macro-RAFT agents and surfactant. Two macro-RAFT agents-hydrophilic poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA27 ) and amphiphilic poly(poly(ethylene glycol) methyl ether methacrylate)-b-polystyrene (PPEGMA27 -b-PS33 )- are examined for the miniemulsion polymerization of styrene. The use of PPEGMA27 (in the presence of sodium dodecyl sulfate (SDS)) results in a slow polymerization rate with a broad particle size. In the absence of SDS, the use of PPEGMA27 -b-PS33 results in a broad particle size distribution due to its inability to form uniform initial droplets whereas the same amphiphilic block copolymer in the presence of SDS yields resulting products with a uniform particle size distribution. The latter exhibits a fashion of controlled polymerization with a high consumption of monomer (98% in 100 min) and a narrow molecular weight distribution throughout the polymerization. This is attributed to the formation of uniform droplets facilitated by SDS in a miniemulsion. The amphiphilic macro-RAFT agent is able to anchor efficiently on the monomer droplet or particle/water interface and form stabilized particles of well-defined PPEGMA27 -b-PS block copolymer, confirmed using dynamic light scattering and transmission electron micrographs.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Polímeros
/
Ácidos Polimetacrílicos
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article