Entity

Time filter

Source Type


Hu J.,Nanjing Southeast University | Zhou Y.,Nanjing Southeast University | He M.,Nanjing Southeast University | Yang X.,Suzhou Sidike New Material Technology Co.
Optical Materials | Year: 2013

This study describes a new approach to using microsphere particles for optical diffusion in a liquid crystal display backlighting unit. We developed a one pot synthesis of polysiloxane@CeO2-poly(methyl methacrylate) hybrid microspheres and examined its physical and chemical properties by powder transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, FT-IR spectra analysis, UV-vis spectra analysis and diffusing abilities analysis. FT-IR spectra analysis and XRD analysis confirmed the hybrid structure of the synthesized materials. The TEM and SEM results indicated that the synthesized materials are core-shell microspheres with a conventional structure. In an anti-radiation experiment the hybrid microspheres exhibited a significant improvement over conventional plastic by effectively absorbing ultraviolet light. When the amount of polysiloxane@CeO2-poly(methyl methacrylate) was increased to 8 wt%, the microspheres blocked almost all UV light, up to 97.5%. This quality alone suggests that polysiloxane@CeO2-poly(methyl methacrylate) hybrid microspheres may be an improvement over materials currently used in conventional optical diffusers. We also characterized diffusing abilities of a novel optical diffuser containing polysiloxane@CeO 2-PMMA core-shell microspheres and found that a polysiloxane diffuser increased in optical diffusing effect as the quantity of polysiloxane@CeO 2-PMMA increased, exceeding the diffusing abilities of conventional optical diffusers. © 2013 Elsevier B.V. All rights reserved. Source


Wang Y.,Nanjing Southeast University | Zhou Y.,Nanjing Southeast University | Zhang T.,Nanjing Southeast University | He M.,Nanjing Southeast University | And 2 more authors.
Applied Surface Science | Year: 2014

The low-emissive membrane materials have potential applications in infrared detecting technologies. Herein, we report a novel LDHs film with low infrared emissivity, which was based on the deposition of the exfoliated LDH nanosheets. The monodispersed hexagonal plate-like particles of Ni-In-CO3 2- LDHs were prepared by coprecipitation method with hydrothermal treatment under optimized conditions. In order to exfoliate the LDHs into nanosheets, acetate-intercalated Ni-In LDHs were prepared by anion-exchange of Ni-In-CO3 2- LDHs. The as-prepared acetate-intercalated LDHs exhibited excellent delaminating behavior in water and unilamellar nanosheets were easily obtained. The resulting positive-charged nanosheets were assembled onto quartz substrates to produce the multilayer films. The infrared emissivity values of all the samples were characterized. It was found that the incorporation of Ni2+ and In3+ in the host layer significantly reduced the infrared emissivity value. Moreover, the value was further reduced by the fabrication of multilayer ultrathin films, which can be ascribed to the dense orderly structure and smooth surface morphology. © 2013 Elsevier B.V. All rights reserved. Source


Zhu Y.,Nanjing Southeast University | Zhou Y.,Nanjing Southeast University | Zhang T.,Nanjing Southeast University | He M.,Nanjing Southeast University | And 3 more authors.
Applied Surface Science | Year: 2012

Lactate-intercalated Co-Fe layered double hydroxides (LDHs) were successfully prepared by coprecipitation and hydrothermal method. In this process, divalent metal ions as precursors can be obtained from the reduction reaction of lactic acid and metal powder (cobalt and ferrous). In order to obtain Fe3+, H2O2 (30%) was used to oxidize Fe2+. Meanwhile, the produced lactate was intercalated into the LDHs interlayers to compensate the positively charged layers. The as-synthesized LDHs were studied by element chemical analysis, powder X-ray diffraction (XRD), FT-IR spectroscopy, thermogravitry (TG) and differential scanning calorimetry (DSC), TEM. The results indicated that the basal spacing value of the LDHs was larger than that of lactate-intercalated Mg-Al or Zn-Al LDHs. It proved that the lactate anions were inserted into the gallery in the form of dimers which made it easy to be delaminated in water. The obtained nanosheets were deposited on the substrates to form the film which was characterized by TEM and AFM, and infrared emissivity value (8-14 μm) was also investigated. The infrared emissivity values of Co-Fe LDHs were lower than that of Zn-Al which took advantage of the special electronic structure in Co and Fe. Besides, the orderly structure and the reduction of the interfacial deficiency of the film made the values further reduced. © 2012 Elsevier B.V. Source


Yang Y.,Nanjing Southeast University | Zhou Y.,Nanjing Southeast University | Ge J.,Nanjing Southeast University | Yang X.,Suzhou Sidike New Material Technology Co.
Materials Research Bulletin | Year: 2012

Optically active polyurethane@indium tin oxide and racemic polyurethane@indium tin oxide nanocomposites (LPU@ITO and RPU@ITO) were prepared by grafting the organics onto the surfaces of modified ITO nanoparticles. LPU@ITO and RPU@ITO composites based on the chiral and racemic tyrosine were characterized by FT-IR, UV-vis spectroscopy, X-ray diffraction (XRD), SEM, TEM, and thermogravimetric analysis (TGA), and the infrared emissivity values (8-14 μm) were investigated in addition. The results indicated that the polyurethanes had been successfully grafted onto the surfaces of ITO without destroying the crystalline structure. Both composites possessed the lower infrared emissivity values than the bare ITO nanoparticles, which indicated that the interfacial interaction had great effect on the infrared emissivity. Furthermore, LPU@ITO based on the optically active polyurethane had the virtue of regular secondary structure and more interfacial synergistic actions between organics and inorganics, thus it exhibited lower infrared emissivity value than RPU@ITO based on the racemic polyurethane. © 2012 Elsevier Ltd. Source


Yang Y.,Nanjing Southeast University | Zhou Y.,Nanjing Southeast University | Ge J.,Nanjing Southeast University | Yang X.,Suzhou Sidike New Material Technology Co.
Reactive and Functional Polymers | Year: 2012

Optically active polyurethanes (PUs) with different specific rotations were synthesized using a hydrogen transfer addition polymerization procedure with isocyanate-phenols of varying enantiomeric excess. The optical activities of the PUs were enhanced with an increase in the enantiomeric excess of the monomers. A helical secondary structure in the PUs with a more compact arrangement of the macromolecular backbones facilitated interchain hydrogen bonding, and the infrared emissivity of the corresponding polymers decreased. The results indicated that the level of order and number of hydrogen bonds in the macromolecule played significant roles in controlling the infrared emissivity. © 2012 Elsevier Ltd. All rights reserved. Source

Discover hidden collaborations