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Limin Wu - One of the best experts on this subject based on the ideXlab platform.

  • the properties of Organic Pigment encapsulated with nano silica via layer by layer assembly technique
    Dyes and Pigments, 2008
    Co-Authors: Junjie Yuan, Guangxin Gu, Wentao Xing, Limin Wu
    Abstract:

    In this paper, an Organic Pigment was coated with nano-silica particles via layer-by-layer self-assembly technique and some properties were investigated. The results revealed that the coating of nano-silica on the surfaces of Pigments could improve the thermal stability, wettability, acid and alkali resistance, and weatherability of the Organic Pigment.

  • Organic Pigment particles coated with titania via sol gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment Particles Coated with Titania via Sol−Gel Process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment particles coated with titania via sol-gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu, Bo You
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte: poly(sodium 4-styrenesulfonate) (PSS) and poly (diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol-gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content. © 2006 American Chemical Society.

  • Encapsulation of Organic Pigment Particles with Silica via Sol-Gel Process
    Journal of Sol-Gel Science and Technology, 2005
    Co-Authors: Junjie Yuan, Shuxue Zhou, Guangxin Gu, Limin Wu
    Abstract:

    This paper presented a novel preparation method of silica coated Organic Pigment. In this approach, the surfaces of the Organic Pigment were first orderly modified by poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by silica via sol-gel process of tetraethylorthosilicate (TEOS). The results showed that PVP, pH value, water and TEOS contents had significant influence on the morphology of the silica encapsulated Organic Pigment. Organic Pigments coated silica by this approach could scatter UV ray with wavelength less than 270 nm, and this scattering property increased with more silica coated.

Junjie Yuan - One of the best experts on this subject based on the ideXlab platform.

  • the properties of Organic Pigment encapsulated with nano silica via layer by layer assembly technique
    Dyes and Pigments, 2008
    Co-Authors: Junjie Yuan, Guangxin Gu, Wentao Xing, Limin Wu
    Abstract:

    In this paper, an Organic Pigment was coated with nano-silica particles via layer-by-layer self-assembly technique and some properties were investigated. The results revealed that the coating of nano-silica on the surfaces of Pigments could improve the thermal stability, wettability, acid and alkali resistance, and weatherability of the Organic Pigment.

  • Organic Pigment particles coated with titania via sol gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment Particles Coated with Titania via Sol−Gel Process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment particles coated with titania via sol-gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu, Bo You
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte: poly(sodium 4-styrenesulfonate) (PSS) and poly (diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol-gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content. © 2006 American Chemical Society.

  • Encapsulation of Organic Pigment Particles with Silica via Sol-Gel Process
    Journal of Sol-Gel Science and Technology, 2005
    Co-Authors: Junjie Yuan, Shuxue Zhou, Guangxin Gu, Limin Wu
    Abstract:

    This paper presented a novel preparation method of silica coated Organic Pigment. In this approach, the surfaces of the Organic Pigment were first orderly modified by poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by silica via sol-gel process of tetraethylorthosilicate (TEOS). The results showed that PVP, pH value, water and TEOS contents had significant influence on the morphology of the silica encapsulated Organic Pigment. Organic Pigments coated silica by this approach could scatter UV ray with wavelength less than 270 nm, and this scattering property increased with more silica coated.

Shuxue Zhou - One of the best experts on this subject based on the ideXlab platform.

  • Organic Pigment Particles Coated with Titania via Sol−Gel Process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment particles coated with titania via sol gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte:  poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol−gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content.

  • Organic Pigment particles coated with titania via sol-gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu, Bo You
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte: poly(sodium 4-styrenesulfonate) (PSS) and poly (diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol-gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content. © 2006 American Chemical Society.

  • Encapsulation of Organic Pigment Particles with Silica via Sol-Gel Process
    Journal of Sol-Gel Science and Technology, 2005
    Co-Authors: Junjie Yuan, Shuxue Zhou, Guangxin Gu, Limin Wu
    Abstract:

    This paper presented a novel preparation method of silica coated Organic Pigment. In this approach, the surfaces of the Organic Pigment were first orderly modified by poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDADMAC), then coated by silica via sol-gel process of tetraethylorthosilicate (TEOS). The results showed that PVP, pH value, water and TEOS contents had significant influence on the morphology of the silica encapsulated Organic Pigment. Organic Pigments coated silica by this approach could scatter UV ray with wavelength less than 270 nm, and this scattering property increased with more silica coated.

  • Organic Pigment particles coated with colloidal nano silica particles via layer by layer assembly
    Chemistry of Materials, 2005
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu
    Abstract:

    An Organic Pigment was successfully coated with colloidal silica particles using the layer-by-layer assembly technique to improve the weatherability and dispersion ability in waterborne systems. It was found that the nano-silica content or the thickness of the nano-silica shell could be modulated by the numbers of both polyelectrolyte layers and nano-silica layers. The first layer of nano-silica assembly obviously increased the particle size of the Organic Pigment, causing a relatively rough surface, an obvious augment in shell thickness, and a broad pore size distribution, but the second and the third layers of nano-silica assembly preferred to fill the pores caused by the first layer of silica, causing a relatively smooth surface, slight increases in shell thickness and surface Si content, and a narrow pore size distribution. The nano-silica particles coated on the surfaces of Organic particles could obviously scatter the UV light especially after the second and third layers of silica assembly.

Bo You - One of the best experts on this subject based on the ideXlab platform.

  • Organic Pigment particles coated with titania via sol-gel process
    Journal of Physical Chemistry B, 2006
    Co-Authors: Junjie Yuan, Shuxue Zhou, Limin Wu, Bo You
    Abstract:

    This paper presented a novel method for the Organic Pigment coated with titania to improve the weatherability and dispersion ability in waterborne system. The Organic Pigment was first orderly adsorbed by two kinds of electrolyte: poly(sodium 4-styrenesulfonate) (PSS) and poly (diallyldimethylammonium chloride) (PDADMAC), then coated by titania via sol-gel process from titanium n-butoxide (TBOT). The effects of the numbers of polyelectrolyte layer, water content, and TBOT content on the morphology, particle size, surface element composition, porosity and pore size, thermal stability, and UV shielding property of the Organic Pigment were systematically investigated. It was found that only two layers of electrolyte adsorption and one-step coating of titania could obviously enhance the UV shielding property even thermal stability of the Organic Pigment. The thickness of the titania layer could be easily tailored by TBOT content. © 2006 American Chemical Society.

N A Bulychev - One of the best experts on this subject based on the ideXlab platform.

  • Ultrasonic treatment assisted surface modification of inOrganic and Organic Pigments in aqueous dispersions
    Journal of the Balkan Tribological Association, 2008
    Co-Authors: N A Bulychev, E. V. Kisterev, I. A. Arutunov, Valentin P. Zubov
    Abstract:

    The colloidal stability and Pigment surface modification of aqueous dispersions of inOrganic Pigments TiO2 (rutile) and Fe2O3 (red) as well as Organic Pigment copper phthalocyanine CuPc (blue) treated in an ultrasonic field in the presence of water-soluble polymers and surfactants was studied. It has been shown that for the inOrganic Pigments TiO2 and Fe2O3 in the absence of polymers and surfactants, ultrasonic treatment results in a fast coagulation of aqueous dispersion. In the presence of ethylhydroxyethylcellulose (EHEC), ultrasonic treatment leads to a significant increase in the stability of aqueous dispersions of TiO2 and Fe2O3, decrease of Pigment particles size from 1.5 to 0.2 mu m, and narrowing of the particle size distribution. Experimental results on measuring the zeta-potential of the particle surface of TiO2 Pigment have verified the assumption that the ultrasonic treatment of aqueous dispersions of Pigment in the presence of EHEC not only results in effective deagglomeration of particles but also activates the adsorption of polymer on freshly-formed surface and facilitates the formation of protective adsorption-solvation layers. For aqueous dispersions of Organic Pigment CuPc, there is a problem of the wetting of its surface. It has been shown that this problem is effectively removed in the presence of polyvinyl alcohol (PVA) with content of residual acetyl groups of 10-17% and molecular weight of 10 000-11 000. The presence of anionogenic dispersant NF gives the same effect. The wetting of CuPc surface results in the colouring of its aqueous dispersion into a bright-blue colour. The colour intensity can be used as a measure of the stability of CuPc aqueous dispersions. It is demonstrated that the value of optical density of CuPc dispersions with the separated solid phase in the presence of PVA and dispersant NF becomes significantly higher as a result of ultrasonic treatment, which indicates an increase in the stability of CuPc aqueous dispersions.

  • application of thermo responsive poly methyl vinyl ether containing copolymers in combination with ultrasonic treatment for Pigment surface modification in Pigment dispersions
    Polymer, 2007
    Co-Authors: N A Bulychev, Valentin P. Zubov, Ondine Confortini, P Kopold, Klaus Dirnberger, T Schauer, F Du Prez, Claus D Eisenbach
    Abstract:

    The process of surface modification of hydrophobic Organic (copper phthalocyanine (CuPc)) as well as hydrophilic inOrganic Pigments (titanium dioxide) in aqueous dispersions by employing tailor-made thermo-responsive copolymers and the colloidal stability have been studied as a function of temperature. The Pigment surface modification is achieved by conventional adsorption and by thermoprecipitation of amphiphilic methyl vinyl ether (MVE) containing block and graft copolymers, exhibiting a lower critical solution temperature (LCST), with poly(isobutyl vinyl ether) blocks and poly(ethylene oxide) side chains, respectively. The effect of mechanical treatment of the Pigment dispersion by ultrasonic power alone or in combination with the LCST property was investigated. The course of the Pigment surface coating process was followed by the electrokinetic sonic amplitude (ESA) method. The temperature-controlled sorption of PMVE-g-PEO graft copolymers on both inOrganic and Organic Pigment surfaces was investigated. It was found that ultrasonic treatment together with LCST thermoprecipitation is a promising method for the surface modification of Pigments with regard to dispersion stability.