Designing Macromolecules on Nanoparticle Surfaces: in Situ Formation of Silica Grafted with Star Chains

Author

Fatimah Aldakheel
Konstantinos Ntetsikas
Arief Yudhanto, Missouri University of Science and TechnlogyFollow
Gilles Lubineau
Nikos Hadjichristidis

Abstract

Herein, we report the synthesis and characterization of asymmetric 3-arm homostar (3h-star) and 3-miktoarm star (3μ-star) chains grafted on silica nanoparticles simultaneously with the formation of silica. We employed high-vacuum anionic polymerization techniques to synthesize well-defined ω-triethoxysilyl (TEOS)-terminated (PS)2PS, (PS)2PI, and (PS)2PI-b-PS macromonomers (polystyrene (PS) and polyisoprene (PI)), which upon hydrolysis/condensation of the terminal TEOS yielded the grafted silica nanoparticles. The molecular characteristics of the precursors (PS)2PS-TEOS, (PS)2PI-TEOS, and (PS)2PI-b-PS-TEOS were determined by proton nuclear magnetic resonance (NMR) spectroscopy and size-exclusion chromatography (SEC). The formation of 3h-star and 3μ-star@SiO2 nanoparticles was demonstrated by Fourier transform infrared spectroscopy, ²⁹Si solid-state NMR, transmission electron microscopy, thermogravimetry, and dynamic light scattering. Blends of 3h-star and 3μ-star@SiO2 with a thermoplastic elastomer (TPE) (PS-b-PI-b-PS), synthesized by anionic polymerization, were obtained by the evaporation of solutions containing the TPE and the grafted nanoparticles. The role of 3h-star and 3μ-star@SiO2 in the mechanical properties and morphological features of the polymer matrices was examined by tensile testing and scanning electron microscopy. This synthetic methodology controls the molecular characteristics, particle size, and grafting density of nanoparticles and enhances the mechanical properties of the final nanocomposites.

Recommended Citation

F. Aldakheel et al., "Designing Macromolecules on Nanoparticle Surfaces: in Situ Formation of Silica Grafted with Star Chains," ACS Applied Polymer Materials, vol. 5, no. 12, pp. 9721 - 9731, American Chemical Society, Dec 2023.

The definitive version is available at https://doi.org/10.1021/acsapm.3c01246

Department(s)

Mechanical and Aerospace Engineering

Comments

King Abdullah University of Science and Technology, Grant None

Keywords and Phrases

anionic polymerization; homostar polymers; in situ formation of polymer@SiO2; mechanical properties; miktoarm star polymers; morphology

International Standard Serial Number (ISSN)

2637-6105

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2025 American Chemical Society, All rights reserved.

Publication Date

08 Dec 2023