ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent (Z-6030) modified ZrO2 nanoparticles, and the morphology, size and its dis...ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent (Z-6030) modified ZrO2 nanoparticles, and the morphology, size and its distribution of nanocomposite particles are investigated. Scanning electron microscopy (SEM) images demonstrate that the methyl methacrylate (MMA) feeding rate has a significant effect on the particle size and morphology. When the MMA feeding rate decreases from 0.42 ml-min-1 to 0.08 ml. min-1, large particles (about 200-550.nm) will not form, and the size distribution become narrow (36-54 nm). The average nanocomposite particles size increases from 34 nm to 55 nm, as the MMA/ZrO2 nanoparticles mass ratio increased from 4 : 1 to 16 : 1. Regular spherical ZrO2/PMMA nanocomposite particles are synthesized when the emulsifier OP-10 concentration is 2 mg.m1-1. The nanocomposite particles could be mixed with VAc-VeoVa10 polymer matrix just by magnetic stirring to prepare the ZrOE/PMMA/VAc-VeoVal0 hybrid coatings. SEM and atomic force microscopy (AFM) photos reveal that the distribution of the ZrO2/PMMA nanocomposite particles in the VAc-VeoVal0 polymer matrix is homogenous and stable. Here, the grafted-PMMA polymer on ZrO2 nanoparticles plays as a bridge which effectively connects the ZrO2 nanoparticles and the VAc-VeoVal0 polymer matrix with improved comparability. In consequence, the hybrid coating with good dispersion stability is obtained.展开更多
Objective: To fabricate polymeric nanocomposites with excellent photoluminescence, magnetic properties, and stability in aqueous solutions, in order to improve specificity and sensitivity of cellular imaging under a ...Objective: To fabricate polymeric nanocomposites with excellent photoluminescence, magnetic properties, and stability in aqueous solutions, in order to improve specificity and sensitivity of cellular imaging under a magnetic field. Methods: Fluoridated LnS+-doped HAP (Ln3+-HAP) NPs and iron oxides (lOs) can be encapsulated with biocompatible polymers via a modified solvent exaction/evaporation technique to prepare polymeric nanocomposites with fluoridated Ln3+-HAP/iron oxide. The nanocomposites were characterized for surface morphology, fluorescence spectra, magnetic properties and in vitro cytotoxicity. Magnetic targeted cellular imaging of such nanocomposites was also evaluated with confocal laser scanning microscope using A549 cells with or without magnetic field. Results: The fabricated nanocomposites showed good stability and excellent luminescent properties, as well as low in vitro cytotoxicity, indicating that the nanocomposites are suitable for biological applications. Nanocomposites under magnetic field achieved much higher cellular uptake via an energy-dependent pathway than those without magnetic field. Conclusion: 1tie nanocomposites fabricated in this study will be a promising tool for magnetic targeted cellular imaging with improved specificity and enhanced selection.展开更多
Based on effective field method,the dynamic effective elastic modulus of polymer matrix composites embedded with dense piezoelectric nano-fibers is obtained,and the interacting effect of piezoelectric surfaces/interfa...Based on effective field method,the dynamic effective elastic modulus of polymer matrix composites embedded with dense piezoelectric nano-fibers is obtained,and the interacting effect of piezoelectric surfaces/interfaces around the nano-fibers is considered.The multiple scattering effects of harmonic anti-plane shear waves between the piezoelectric nano-fibers with surface/interface are averaged by effective field method.To analyze the interacting results among the random nano-fibers,the problem of two typical piezoelectric nano-fibers is introduced by employing the addition theorem of Bessel functions.Through numerical calculations,the influence of the distance between the randomly distributed piezoelectric nano-fibers under different surface/interface parameters is analyzed.The effect of piezoelectric property of surface/interface on the effective shear modulus under different volume fractions is also examined.Comparison with the simplified cases is given to validate this dynamic electro-elastic model.展开更多
基金Supported by Production, Teaching & Research Combination Project for Universities in Guangdong Province(cgzhzd0904),Department of Education of Guangdong Province, China
文摘ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent (Z-6030) modified ZrO2 nanoparticles, and the morphology, size and its distribution of nanocomposite particles are investigated. Scanning electron microscopy (SEM) images demonstrate that the methyl methacrylate (MMA) feeding rate has a significant effect on the particle size and morphology. When the MMA feeding rate decreases from 0.42 ml-min-1 to 0.08 ml. min-1, large particles (about 200-550.nm) will not form, and the size distribution become narrow (36-54 nm). The average nanocomposite particles size increases from 34 nm to 55 nm, as the MMA/ZrO2 nanoparticles mass ratio increased from 4 : 1 to 16 : 1. Regular spherical ZrO2/PMMA nanocomposite particles are synthesized when the emulsifier OP-10 concentration is 2 mg.m1-1. The nanocomposite particles could be mixed with VAc-VeoVa10 polymer matrix just by magnetic stirring to prepare the ZrOE/PMMA/VAc-VeoVal0 hybrid coatings. SEM and atomic force microscopy (AFM) photos reveal that the distribution of the ZrO2/PMMA nanocomposite particles in the VAc-VeoVal0 polymer matrix is homogenous and stable. Here, the grafted-PMMA polymer on ZrO2 nanoparticles plays as a bridge which effectively connects the ZrO2 nanoparticles and the VAc-VeoVal0 polymer matrix with improved comparability. In consequence, the hybrid coating with good dispersion stability is obtained.
基金supported by National Natural Science Foundation of China (Grant No. 21506161, 31270019)National Key Basic Research Program of China (973 Program) (Grant No. 2011CB933100, 2011CB932402)+1 种基金Guangdong Natural Science Funds for Distinguished Young Scholar (Grant No. 2014A030306036)open funds from the Key Laboratory of Biomedical Materials in Tianjin
文摘Objective: To fabricate polymeric nanocomposites with excellent photoluminescence, magnetic properties, and stability in aqueous solutions, in order to improve specificity and sensitivity of cellular imaging under a magnetic field. Methods: Fluoridated LnS+-doped HAP (Ln3+-HAP) NPs and iron oxides (lOs) can be encapsulated with biocompatible polymers via a modified solvent exaction/evaporation technique to prepare polymeric nanocomposites with fluoridated Ln3+-HAP/iron oxide. The nanocomposites were characterized for surface morphology, fluorescence spectra, magnetic properties and in vitro cytotoxicity. Magnetic targeted cellular imaging of such nanocomposites was also evaluated with confocal laser scanning microscope using A549 cells with or without magnetic field. Results: The fabricated nanocomposites showed good stability and excellent luminescent properties, as well as low in vitro cytotoxicity, indicating that the nanocomposites are suitable for biological applications. Nanocomposites under magnetic field achieved much higher cellular uptake via an energy-dependent pathway than those without magnetic field. Conclusion: 1tie nanocomposites fabricated in this study will be a promising tool for magnetic targeted cellular imaging with improved specificity and enhanced selection.
基金supported by the National Natural Science Foundation of China(Grant Nos.11172185 and 11272222)the Natural Science Foundation for Outstanding Young Researcher in Hebei Province of China(Grant No.A201410015)+1 种基金the National Key Basic Research Program of China(Grant No.2012CB723300)the Training Program for Leading Talent in University Innovative Research Team in Hebei Province(Grant No.LJRC006)
文摘Based on effective field method,the dynamic effective elastic modulus of polymer matrix composites embedded with dense piezoelectric nano-fibers is obtained,and the interacting effect of piezoelectric surfaces/interfaces around the nano-fibers is considered.The multiple scattering effects of harmonic anti-plane shear waves between the piezoelectric nano-fibers with surface/interface are averaged by effective field method.To analyze the interacting results among the random nano-fibers,the problem of two typical piezoelectric nano-fibers is introduced by employing the addition theorem of Bessel functions.Through numerical calculations,the influence of the distance between the randomly distributed piezoelectric nano-fibers under different surface/interface parameters is analyzed.The effect of piezoelectric property of surface/interface on the effective shear modulus under different volume fractions is also examined.Comparison with the simplified cases is given to validate this dynamic electro-elastic model.