Designer Core–Shell Nanoparticles as Polymer Foam Cell Nucleating Agents: The Impact of Molecularly Engineered Interfaces

TiO2-g-Polystyrene(PS) nano-microspheres were prepared by grafted styrene monomer on the surface of nano-TiO2 particles via emulsion polymerization, and its surface and morphology were studied by Transmission electron microscopes(TEM), Fourier transform infrared spectroscopy(FTIR) and thermal gravimetric analysis(TGA). The results showed that the TiO2-g-PS nano-microsphere had a structure of sphericity composed of TiO2 and PS as core and shell respectively. The core-shell nanoparticles were subsequently used as filler in a PS matrix, and the impact strength of the TiO2-g-PS/PS composites were studied. The results showed that the impact strength of the composite material could be improved obviously, the maximum value of impacted strength of the TiO2-g-PS/PS was 1.75kJ/m2, which was 180% higher than that of pure PS. Drawing from the results, it could be confirmed that these core-shell TiO2-g-PS nanosphere fillers could toughen the PS matrix.

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Investigation on the impact of different stabilizing agents on structural, optical properties of Ag@SnO2 core - shell nanoparticles and its biological applications

Journal of Molecular Liquids ◽

10.1016/j.molliq.2020.112951 ◽

2020 ◽

Vol 307 ◽

pp. 112951 ◽

Cited By ~ 2

Author(s):

R. Vanathi Vijayalakshmi ◽

Ravichandran Kuppan ◽

P. Praveen Kumar

Keyword(s):

Optical Properties ◽

Core Shell ◽

Biological Applications ◽

Shell Nanoparticles ◽

Stabilizing Agents ◽

Core Shell Nanoparticles ◽

The Impact

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Modifying Cement Hydration with NS@PCE Core-Shell Nanoparticles

Advances in Materials Science and Engineering ◽

10.1155/2017/3823621 ◽

2017 ◽

Vol 2017 ◽

pp. 1-13 ◽

Cited By ~ 9

Author(s):

Yue Gu ◽

Qianping Ran ◽

Wei She ◽

Jiaping Liu

Keyword(s):

Cement Hydration ◽

Fine Particles ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Core Shell ◽

Shell Nanoparticles ◽

Pozzolanic Reactivity ◽

Characteristic Values ◽

Core Shell Nanoparticles ◽

The Impact

It is generally accepted that fine particles could accelerate cement hydration process, or, more specifically, this accelerating effect can be attributed to additional surface area introduced by fine particles. In addition to this view, the surface state of fine particles is also an important factor, especially for nanoparticles. In the previous study, a series of nano-SiO2-polycarboxylate superplasticizer core-shell nanoparticles (NS@PCE) were synthesized, which have a similar particle size distribution but different surface properties. In this study, the impact of NS@PCE on cement hydration was investigated by heat flow calorimetry, mechanical property measurement, XRD, and SEM. Results show that, among a series of NS@PCE, NS@PCE-2 with a moderate shell-core ratio appeared to be more effective in accelerating cement hydration. As dosage increases, the efficiency of NS@PCE-2 would reach a plateau which is quantified by various characteristic values. Compressive strength results indicate that strength has a linear correlation with cumulative heat release. A hypothesis was proposed to explain the modification effect of NS@PCE, which highlights a balance between initial dispersion and pozzolanic reactivity. This paper provides a new understanding for the surface modification of supplementary cementitious materials and their application and also sheds a new light on nano-SiO2 for optimizing cement-based materials.

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Iron Oxide–Silica Core–Shell Nanoparticles Functionalized with Essential Oils for Antimicrobial Therapies

Antibiotics ◽

10.3390/antibiotics10091138 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1138

Author(s):

Cristina Chircov ◽

Maria-Florentina Matei ◽

Ionela Andreea Neacșu ◽

Bogdan Stefan Vasile ◽

Ovidiu-Cristian Oprea ◽

...

Keyword(s):

Electron Microscopy ◽

Essential Oils ◽

Synthesis Method ◽

Gas Chromatography Mass Spectrometry ◽

In Vitro Tests ◽

Core Shell ◽

Shell Nanoparticles ◽

Nanostructured Systems ◽

Core Shell Nanoparticles ◽

The Impact

Recent years have witnessed a tremendous interest in the use of essential oils in biomedical applications due to their intrinsic antimicrobial, antioxidant, and anticancer properties. However, their low aqueous solubility and high volatility compromise their maximum potential, thus requiring the development of efficient supports for their delivery. Hence, this manuscript focuses on developing nanostructured systems based on Fe3O4@SiO2 core–shell nanoparticles and three different types of essential oils, i.e., thyme, rosemary, and basil, to overcome these limitations. Specifically, this work represents a comparative study between co-precipitation and microwave-assisted hydrothermal methods for the synthesis of Fe3O4@SiO2 core–shell nanoparticles. All magnetic samples were characterized by X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetry and differential scanning calorimetry (TG-DSC), and vibrating sample magnetometry (VSM) to study the impact of the synthesis method on the nanoparticle formation and properties, in terms of crystallinity, purity, size, morphology, stability, and magnetization. Moreover, the antimicrobial properties of the synthesized nanocomposites were assessed through in vitro tests on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. In this manner, this study demonstrated the efficiency of the core–shell nanostructured systems as potential applications in antimicrobial therapies.

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