Preparation and Characterization of Core-Shell Latex Containing PDMS in the Shell

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Baotan Zhang ◽  
Bailing Liu ◽  
Shunsheng Cao ◽  
Xiaobo Deng

AbstractIn this paper, the composite latex particles with a polyacrylate (PA) core and a polydimethylsiloxane (PDMS) shell via 3-(methacryloxypropyl)- trimethoxy silane (MPS) as the medium to link the core and shell were prepared by semicontinuous seeded emulsion polymerization and were characterized by transmission electron microscopy (TEM), FT-IR, particle size analyzer and X-ray photoelectron spectroscopy (XPS). The TEM images indicated that the particles containing organic siloxane (D-40) displayed an evident core/shell structure. Additionally, the study by FT-IR and XPS also revealed that D4 could be grafted onto the surface of polyacrylate core because there appeared the characteristic peaks of Si-O-Si group and Si 2s and Si 2p in the spectra of FT-IR and XPS respectively. Besides, the atomic ratio of C/Si on the surface of the core/shell particles (D-40) was close to the ratio of C/Si in the latex of pure PDMS that could prove the PA particles were fully covered by PDMS and the properties of PDMS should be embodied in a maximal level. In order to testify the result, the surface properties of the films produced from the core/shell particles were also investigated by the static contact angle method. Compared with the copolymer of PA, the core/shell particles were more effective to create hydrophobic surface, so, the introduction of D4 was capable of obvious increase in water repellency.

2011 ◽  
Vol 284-286 ◽  
pp. 2224-2229 ◽  
Author(s):  
Hong Yan Zhang ◽  
Jun Wang ◽  
Shao Hua Fan

In this paper, we report the synthesis of the bifunctional Fe3O4@SiO2@Eu-polyoxometalates particles. The magnetite nanoparticles (Fe3O4) homogeneously coated with silica spheres prepared with the Stöber method. The so-obtained Fe3O4@SiO2 core/shell particles were modified by 3-aminopropyltriethoxysilane and finally grafted with the luminescent Europium -polyoxometalates. The core-shell particles were characterized by scanning electron microscopy, transmission electron microscopy, FT-IR, UV, magnetism and luminescence spectroscopy. The results indicated that the core-shell particles show both interesting luminescence and magnetic properties.


2011 ◽  
Vol 332-334 ◽  
pp. 387-390
Author(s):  
Chun Lei Xu ◽  
Yi Hu ◽  
Jin Qiang Liu ◽  
Sheng Peng Wang ◽  
Shao Min Qu ◽  
...  

Vinyl-endblocked polyurethanes were prepared from polyether diols(N210), isophorone diisocyanate (IPDI), dimethylol propionic acid (DMPA) and 2-hydroxyethyl acrylate (HEA). The core-shell structure acrylic-polyurethane composite emulsion was prepared by seeded emulsion polymerization of methyl methacrylate (MMA) and butyl acrylate (BA) using the polyurethanes emulsions as seeded emulsions. The core and shell regions were occupied by acrylic polymer and polyurethane, respectively. Because polyurethanes were vinyl-endblocked, acrylic monomers could graft partially to them. The formation of core-shell structure was observed by transmission electron microscopy (TEM). The structure and properties of dried film were studied by Fourier-transform infrared spectroscopy (FT-IR) and TGA.


2020 ◽  
Vol 65 (10) ◽  
pp. 904
Author(s):  
V. O. Zamorskyi ◽  
Ya. M. Lytvynenko ◽  
A. M. Pogorily ◽  
A. I. Tovstolytkin ◽  
S. O. Solopan ◽  
...  

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.


2015 ◽  
Vol 3 (7) ◽  
pp. 3988-3994 ◽  
Author(s):  
Xiang Li ◽  
Fangyuan Gai ◽  
Buyuan Guan ◽  
Ye Zhang ◽  
Yunling Liu ◽  
...  

Fe@C yolk–shell particles were synthesized by reducing the core with its own carbon shell to achieve the effective removal of 4-chlorophenol from water.


Polymer ◽  
2016 ◽  
Vol 99 ◽  
pp. 324-331 ◽  
Author(s):  
Waraporn Wichaita ◽  
Duangporn Polpanich ◽  
Teeraporn Suteewong ◽  
Pramuan Tangboriboonrat

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Su-Ryeon Yun ◽  
Gyeong-Ok Kim ◽  
Chan Woo Lee ◽  
Nam-Ju Jo ◽  
Yongku Kang ◽  
...  

Polyaniline (Pani) and polypyrrole (Ppy) half hollow spheres with different shell thicknesses were successfully synthesized by three steps process using polystyrene (PS) as the core. The PS core was synthesized by emulsion polymerization. Aniline and pyrrole monomers were polymerized on the surface of the PS core. The shells of Pani and Ppy were fabricated by adding different amounts of aniline and pyrrole monomers. PS cores were dissolved and removed from the core shell structure by solvent extraction. The thicknesses of the Pani and Ppy half hollow spheres were observed by FE-SEM and FE-TEM. The chemical structures of the Pani and Ppy half hollow spheres were characterized by FT-IR spectroscopy and UV-Vis spectroscopy. The shell thicknesses of the Pani half hollow spheres were 30.2, 38.0, 42.2, 48.2, and 52.4 nm, while the shell thicknesses of the Ppy half hollow spheres were 16.0, 22.0, 27.0, and 34.0 nm. The shell thicknesses of Pani and Ppy half hollow spheres linearly increased as the amount of the monomer increased. Therefore, the shell thickness of the Pani and Ppy half hollow spheres can be controlled in these ranges.


e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Guangfeng Wu ◽  
Yue Tao ◽  
Hong Kang ◽  
Huixuan Zhang

AbstractThe stability of core-shell particles (CSPs) with butyl acrylate (BA) as the core and methyl methacrylate (MMA)/glycidyl methacrylate (GMA) mixture in various compositions as the shell was investigated by turbidity measurements. The experiments demonstrate that lower amount addition of GMA could not improve the latex stability. When the amount of GMA exceeded 2% of the total reactants, it began to improve the stability of the latex. With the increasing content of GMA, the latex became more and more stable. On the other hand, experimental data also show that the stability was improved by increasing the concentration of sodium dodecyl sulfate (SDS).


2005 ◽  
Vol 13 (7) ◽  
pp. 721-726
Author(s):  
Shunsheng Cao ◽  
Xiaobo Deng ◽  
Bailing Liu

Core-shell microspheres ranging in average diameter from 12.829 to 15.039 μm, with a poly butyl methacrylate (BMA) core, and a poly 3-(methacryloxypropyl)-trimethoxysilane (MATS) shell, were prepared with methanol as the dispersion medium, by a successive seeding method under kinetically controlled conditions. To date, although some of particles (PSi/PA) have been prepared by seeded emulsion polymerisation, only a few core/shell (PA/PSi) microspheres have been reported the literatures. To prepare core/shell (PA/PSi), the core was first synthesized by dispersion polymerisation and to form seeds; addition of MATS monomer was started after 90~95% conversion of the BMA. The reaction was prolonged for another 12 h to achieve complete consumption of MATS monomer. Microspheres; containing hydrophilic PBMA as the core and hydrophobic PMATS as the shell, were successfully formed through the free radical of surface in the core. The particles morphology and size distribution were examined using a Transmission electron microscope and a Malvern Master Sizer/E particle size analyser, respectively.


1986 ◽  
Vol 32 (5) ◽  
pp. 4865-4871 ◽  
Author(s):  
Yoshinobu Nakamura ◽  
Haruo Tabata ◽  
Hideto Suzuki ◽  
Kazuo Iko ◽  
Masayoshi Okubo ◽  
...  

2015 ◽  
Vol 33 ◽  
pp. 27-37 ◽  
Author(s):  
Jhin Hong You ◽  
Yi Yin Kuo ◽  
Keh Ying Hsu

This study aims to describe the preparation and characterization of SiO2/TiO2 core-shell particles. In order to prepare the homogenous SiO2/TiO2 inorganic compounds by sol-gel process, SiO2 particles were used as the core, AcAc served as a chelating agent to chelate with TTIP (which was used as the precursor to TiO2), and PEG was added to stabilize the hydrolysis/condensation process. In addition, the ionic surfactant (SDS) and the nonionic surfactant (PVP) dispersed the core-shell particles. In order to improve the crystal structure, a high temperature was used to calcine the core-shell particles. The influence of various reaction parameters on the size, morphology and composition of the particles was also investigated. The properties of the particles were analyzed by electron microscopy, fourier transform infrared analysis, thermogravimetric analysis and powder X-ray diffraction.


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