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Gaoyao, China

Qin D.,Nankai University | Yu J.,Nankai University | Bian G.,Dynea Ltd. Co. | Qi Y.,Dynea Ltd. Co. | And 2 more authors.
Chinese Journal of Chemistry | Year: 2014

Double-shelled zirconia/titania (ZrO2/TiO2) hollow microspheres were prepared by the selective removal of the polymer components via the calcination of the corresponding tetra-layer poly(N,N′- methylenebisacryl amide-co-methacrylic acid) (P(MBA-co-MAA))/Zr(OH) 4/poly(ethyleneglycol dimethacrylate-co-methacrylic acid) (P(EGDMA-co-MAA))/TiO2 hybrid microspheres. These tetra-layer microspheres were synthesized by the combination of the distillation copolymerization of N,N(-methylenebisacryl amide-co-methacrylic acid (MBA) or ethyleneglycol dimethacrylate (EGDMA) crosslinker and methacrylic acid (MAA) for the preparation of polymer core and third-layer as well as the controlled sol-gel hydrolysis of inorganic precursors for the construction of zirconium hydroxide (Zr(OH)4) and titania (TiO2) layers. The thicknesses of zirconia and titania shell-layers were conveniently controlled via varying the feed of zirconium n-butoxide (Zr(OBu)4) and titanium tetrabutoxide (TBOT) during the sol-gel hydrolysis, while the sizes of polymer layers were tuned through a multi-stage distillation precipitation copolymerization. The structure and morphology of the resultant microspheres were characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), X-ray photoelectronic spectroscopy (XPS), and thermogrametric analysis (TGA). Double-shelled hollow ZrO2/TiO 2 microspheres were synthesized via combination of the distillation precipitation polymerization for the synthesis of polymeric components and the controlled sol-gel hydrolysis for the preparation of inorganic layers to construct P(MBA-co-MAA)/Zr(OH)4/P(EGDMA-co-MAA)/TiO2 tetra-layer microspheres together with the subsequent calculation for the selective removal of the organic templates. Copyright © 2014 SIOC, CAS, Shanghai & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Liu B.,Nankai University | Sun S.,Nankai University | Gao Z.,Nankai University | Zhang D.,Nankai University | And 4 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2014

The silica-g-poly[2-(N,N-dimethyl amino)ethyl methacrylate] (SiO2-g-PDMAEMA) hybrid microspheres with polymer brushes were synthesized by the surface-grafted atom transfer radical polymerization (ATRP) from the surface alkyl bromide functionalized silica nanospheres. The inorganic nanosphere as surface-initiating polymerization site was prepared by the amide reaction of 2-bromoisobutyryl bromide with the surface amino group of silica via modification with (3-aminopropyl) trimethoxysilane (APS). The grafted PDMEMA brushes stabilized metallic nanocolloids (silver and palladium) were prepared by the in situ reduction of the inorganic salt precursors (AgNO3 and PdCl2) through the coordination effect of the amino groups to the metallic atom (Au, Ag). The catalytic properties of PDMAEMA brush-stabilized silver and palladium metallic nanocolloids were investigated via the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AnP) by sodium borohydride (NaBH4) as a model reaction with a facilely recoverable and stable catalytic property. The resultant hybrid microspheres were characterized by transmission electron microscopy (TEM), thermal gravimetric analyzer (TGA), Fourier infrared (FT-IR) spectra, and inductive coupled plasma emission spectrum (ICP). © 2014 Elsevier B.V. Source

Zhang W.,Nankai University | Liu B.,Nankai University | Zhang B.,Nankai University | Bian G.,Dynea Ltd. Co. | And 3 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2015

Monodisperse magnetic sandwiched magnetite@gold/poly(ethyleneglycol methacrylate) (Fe3O4@Au/PEGDMA) core-shell microspheres were designed and prepared. The whole synthetic procedure mainly involved hydrothermal method for preparation of magnetite core with subsequent modification of (3-aminopropyl)trimethoxysilane (APS) for introduction of the surface amino groups, distillation precipitation polymerization for preparation of the P(EGDMA) shell and in situ reduction of gold precursor HAuCl4 for formation of the sandwiched Au nanoparticles. The thicknesses of the outer polymeric shells were well-controlled via altering the weight ratios of EGDMA monomers to magnetite core during polymerization. The catalytic activity of the sandwiched Fe3O4-Au@P(EGDMA) magnetic microsphere was studied by the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AnP) as a model reaction. These magnetic microspheres were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectra (FT-IR), thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). © 2014 Elsevier B.V. Source

Song T.,Henan University | Song T.,Nankai University | Zhou M.,Nankai University | Liu W.,Tianjin Polytechnic University | And 4 more authors.
Colloid and Polymer Science | Year: 2014

Narrow disperse poly(divinylbenzene-co-glycidyl methacrylate) (P(DVB-co-GMA)) microspheres with reactive epoxy group were prepared by distillation precipitation copolymerization of divinylbenzene (DVB) and glycidyl methacrylate (GMA) with benzoyl peroxide (BPO) as initiator in neat acetonitrile. The epoxy group was modified with ethylenediamine (EDA) for transferring to amino group, which was used as a stabilizer for the gold metallic nanocolloids during the in situ reduction of gold chloride trihydrate (HAuCl4) with sodium borohydride (NaBH4) as a reductant. The catalytic properties of the microsphere-stabilized gold nanocolloids (P(DVB-co-GMA)-NH2@Au) were investigated by the reduction of aqueous 4-nitrophenol (4-NP) to 4-aminophenol (4-AnP) with NaBH4 as reductant. The resultant microspheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectra (FT-IR), elemental analysis (EA), Zeta potential, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP) mission spectrum, and ultraviolet–visible spectroscopy. © 2014, Springer-Verlag Berlin Heidelberg. Source

Zhang W.,Nankai University | Si X.,Nankai University | Liu B.,Nankai University | Bian G.,Dynea Ltd. Co. | And 3 more authors.
Journal of Colloid and Interface Science | Year: 2015

One-dimensional (1D) magnetic Fe3O4/P(MBAAm-co-MAA) nanochains were prepared by distillation-precipitation polymerization of MBAAm and MAA in the presence of Fe3O4 nanoparticles as building blocks under a magnetic heating stirrer, which played two critical roles: serving as magnetic field to induce the self-assembly of Fe3O4 nanoparticles into 1D nanochains and providing thermal energy to induce the polymerization of MAA and MBAAm on the surface of the Fe3O4 nanoparticles. The thickness of the P(MBAAm-co-MAA) layer can be easily tuned by adjusting the successive polymerization steps. The polymer layer that contained carboxyl groups was used as stabilizers for loading Ag nanoparticles and the reaction locus for deposition of outer silica layer via a sol-gel method in presence of C18TMS as the pore directing agent for tri-layer nanochains. The corresponding hollow mesoporous silica nanochains with movable maghemite cores (γ-Fe2O3atmSiO2) were produced after removal of the polymer mid-layer and the alkyl groups of the pore directing agent via calcination of the tri-layer nanochains at high temperature. The Fe3O4/P(MBAAm-co-MAA)/Ag nanochains exhibited a highly catalytic efficiency and well reusable property toward the reduction of nitrophenol. Furthermore, the γ-Fe2O3atmSiO2 nanochains possessed hollow mesoporous structure and high specific surface area (197.2m2g-1) were used as a drug carrier, which displayed a controlled release property. © 2015 Elsevier Inc. Source

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