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  • Silica‐PMMA hairy nanoparticles prepared via phase transfer‐assisted aqueous miniemulsion atom transfer radical polymerization
Title: Silica‐PMMA hairy nanoparticles prepared via phase transfer‐assisted aqueous miniemulsion atom transfer radical polymerization
Abstract Hairy nanoparticles (HNPs) constitute a class of hybrid nanocomposites that are resistant to aggregation and agglomeration, although the green, large‐scale synthesis of HNPs remains a challenge. In this work, 25 nm‐diameter silica‐core HNPs with a poly(methyl methacrylate) (PMMA) shell were synthesized using a graft‐from approach in aqueous miniemulsion, employing atom transfer radical polymerization with activators regenerated by electron transfer (ARGET‐ATRP). In particular, this work used tetrabutylammonium bromide (TBAB)‐assisted phase transfer of monomer, markedly improving upon earlier methods by showing that phase transfer could take place in the absence of organic solvents. Furthermore, syntheses with selected monomer addition rates produced HNP graft densities ranging from 0.011 to 0.017 chains/nm2and shell thicknesses ranging from 2.5 to 11 nm. Finally, analysis of reaction kinetics revealed that shell growth reached completion in as little as 2 hr, confirmed by the synthesis of >1 g of PMMA‐shell HNPs in a reduced timeframe.  more » « less
Award ID(s):
1905403
PAR ID:
10540042
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
John Wiley & Sons
Date Published:
Journal Name:
Journal of Polymer Science
Volume:
58
Issue:
17
ISSN:
2642-4150
Page Range / eLocation ID:
2310 to 2316
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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