Structurally well-defined polymer-grafted nanoparticle hybrids are highly sought after for a variety of applications, such as antifouling, mechanical reinforcement, separations, and sensing. Herein, we report the synthesis of poly(methyl methacrylate) grafted- and poly(styrene) grafted-BaTiO3 nanoparticles using activator regeneration via electron transfer (ARGET ATRP) with a sacrificial initiator, atom transfer radical polymerization (normal ATRP), and ATRP with sacrificial initiator, to understand the role of the polymerization procedure in influencing the structure of nanoparticle hybrids. Irrespective of the polymerization procedure adopted for the synthesis of nanoparticle hybrids, we noticed PS grafted on the nanoparticles showed moderation in molecular weight and graft density (ranging from 30,400 to 83,900 g/mol and 0.122 to 0.067 chain/nm2) compared to PMMA-grafted nanoparticles (ranging from 44,620 to 230,000 g/mol and 0.071 to 0.015 chain/nm2). Reducing the polymerization time during ATRP has a significant impact on the molecular weight of polymer brushes grafted on the nanoparticles. PMMA-grafted nanoparticles synthesized using ATRP had lower graft density and considerably higher molecular weight compared to PS-grafted nanoparticles. However, the addition of a sacrificial initiator during ATRP resulted in moderation of the molecular weight and graft density of PMMA-grafted nanoparticles. The use of a sacrificial initiator along with ARGET offered the best control in achieving lower molecular weight and narrow dispersity for both PS (37,870 g/mol and PDI of 1.259) and PMMA (44,620 g/mol and PDI of 1.263) nanoparticle hybrid systems.
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Silica‐PMMA hairy nanoparticles prepared via phase transfer‐assisted aqueous miniemulsion atom transfer radical polymerization
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- NSF-PAR ID:
- 10453521
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 58
- Issue:
- 17
- ISSN:
- 2642-4150
- Page Range / eLocation ID:
- p. 2310-2316
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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