Deformation of raspberry-like polymer composite particles by colloidal fusion

Hybrid microspheres with a polystyrene core coated with magnetite nanoparticles were prepared by two techniques. Firstly, monodispersed functional polystyrene latex particles were prepared by emulsion polymerization. In a general way chemical groups may be introduced through polymerizable surfactant or functional monomer. Magnetite acidic or alkaline sol was added in, then magnetite nanoparticles were absorbed onto latex particles by electrostatic attraction and core-shell composite particles were formed. Secondly, core-shell composite particles were prepared by miniemulsion polymerization. To modify the tendency of conglomeration of magnetite and increase the amount of magnetic particles onto the composite particles, silane coupling agent MPS was used as surface modification agent for magnetite. A series of different size and coating morphology magnetic hybrid particles were prepared through the adjustment of some experiment parameters. The obtained functional core-shell particles were characterized by FTIR, TEM, etc.

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Al/Al2O3 Core-Shell Particles Synthesized by Wet-Chemical Based Route

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.313.63 ◽

2006 ◽

Vol 313 ◽

pp. 63-68 ◽

Cited By ~ 1

Author(s):

Hua Min Kou ◽

Jing Kun Guo ◽

Jing Wang ◽

Yu Bai Pan

Keyword(s):

Composite Materials ◽

Composite Particles ◽

Core Shell ◽

Coating Process ◽

Coated Particles ◽

Wet Chemical ◽

Shell Particles ◽

Core Particles

Coating process is attracting more and more attention in the preparation of composite materials mainly due to its predominance in the improvement of the uniformity for different phases. The formation of nanosize alumina shells on the aluminum core particles by a wet-chemical based route was investigated and the composite particles were characterized using TG/DSC, XRD, SEM, TEM, XPS. An enhancement of cermet properties can be expected by using these coated particles as initial powders.

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Seed Adsorption Synthesis and Characterization of PMMA/PAN Particles with Core-Shell Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.163 ◽

2013 ◽

Vol 712-715 ◽

pp. 163-168

Author(s):

Wei Chian ◽

Ying Li ◽

Hao Yang ◽

Xia Wang

Keyword(s):

Shell Structure ◽

Process Condition ◽

Morphological Observation ◽

Composite Particles ◽

Core Shell ◽

Adsorption Method ◽

Second Stage ◽

Core Shell Structure ◽

Shell Particles

Narrowly-distributed poly (methyl methacrylate)/polyacrylonitrile (PMMA/PAN) core-shell particles with a target use as the precursor for fabricating carbon microspheres and carbon nanotubes (CNTs) were prepared using the seed adsorption method. PMMA, acrylonitril (AN) and potassium persulfate (KPS) were used as the seed latex, the second-stage monomer (shell monomer) and the initiator, respectively. The effect of process parameters, such as monomer adsorption time, monomer/initiator stoichiometry, presence of surfactant as well as reaction temperature and stirring strength etc., on the morphology and size distribution of the PMMA/PAN composite particles was studied. The process condition under which uniform PMMA/PAN composite particles can form was then identified. Morphological observation by SEM revealed that upon the formation of the core-shell structure, smooth surface of PMMA spheres changed into rambutan-like rough structures.

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Magnetic Properties of Fe3O4/CoFe2O4 Composite Nanoparticles with Core/Shell Architecture

Ukrainian Journal of Physics ◽

10.15407/ujpe65.10.904 ◽

2020 ◽

Vol 65 (10) ◽

pp. 904

Author(s):

V. O. Zamorskyi ◽

Ya. M. Lytvynenko ◽

A. M. Pogorily ◽

A. I. Tovstolytkin ◽

S. O. Solopan ◽

...

Keyword(s):

Magnetic Properties ◽

Spinel Ferrite ◽

Composite Nanoparticles ◽

Core Shell ◽

Cofe2o4 Nanoparticles ◽

Core Diameter ◽

The Core ◽

Shell Particles ◽

Interface Parameters ◽

Shell Composite

Magnetic properties of the sets of Fe3O4(core)/CoFe2O4(shell) composite nanoparticles with a core diameter of about 6.3 nm and various shell thicknesses (0, 1.0, and 2.5 nm), as well as the mixtures of Fe3O4 and CoFe2O4 nanoparticles taken in the ratios corresponding to the core/shell material contents in the former case, have been studied. The results of magnetic research showed that the coating of magnetic nanoparticles with a shell gives rise to the appearance of two simultaneous effects: the modification of the core/shell interface parameters and the parameter change in both the nanoparticle’s core and shell themselves. As a result, the core/shell particles acquire new characteristics that are inherent neither to Fe3O4 nor to CoFe2O4. The obtained results open the way to the optimization and adaptation of the parameters of the core/shell spinel-ferrite-based nanoparticles for their application in various technological and biomedical domains.

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