Macroporous materials comprising DNA were fabricated with the colloidal crystal template. First, DNA and diazoresin (DR) molecules are fully filled into the voids of a colloidal crystal template. After thermal treatment and removal of the colloids, DNA porous materials with highly ordered structure were obtained.
View Article and Find Full Text PDFThe luminescence porous materials of CdTe or CdSe nanocrystals (NCs) were prepared by filling the corresponding NCs into the voids of colloidal crystal by co-deposition of polymer beads and NCs. After removing the beads with tetrahydrofuran (THF), the 3D-ordered porous materials of CdTe (or CdSe) NCs were obtained. The wavelength of maximum photoluminescence of the NCs porous material shows obvious red shift compared with their aqueous dispersion.
View Article and Find Full Text PDFBinary colloidal crystals (BCCs) were prepared from two kinds of poly(styrene-methyl methacrylate-acrylic acid) colloids approximately 190 and approximately 380 nm in diameter by the codeposition method. A variety of array patterns of BCCs were observed and characterized by AFM and SEM. The significance of these colloidal arrays in crystallography has been discussed preliminarily.
View Article and Find Full Text PDFStable, ultrathin DNA micropatterns were fabricated from photosensitive polymer diazoresin (DR) through a self-assembly technique. The micropatterns were achieved on LBL ultrathin film after UV exposure through a photomask. The patterns were characterized systematically with scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy and fluorescence microscopy.
View Article and Find Full Text PDFJ Colloid Interface Sci
May 2002
Novel multilayer ultrathin films of PR-SDS-PC were fabricated by employing the complex of phenolic resin (PR) and sodium dodecyl sulfate (SDS) as a "complex polyanion" and various polycations (PCs). The resulting films were etched quickly when being immersed in polar organic solvents due to the weak hydrophobic interaction between PR and SDS. By employing the photosensitive diazo resin (DR) as PC, the stability of the PR-SDS-DR film increases significantly after UV irradiation, because a covalent crosslinking structure forms in the film.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2005
Chiral polyaniline composite (CPAC) thin films were fabricated by self-assembly using diazoresin (DR) and CPAC. The weak linkage between the DR and CPAC of the film will convert to covalent bonds under UV irradiation or heating, and the thin film becomes very stable toward polar solvents and electrolyte aqueous solutions. Core-shell particles with stable DR/CPAC shell and polystyrene (PS) core can be prepared by similar methods.
View Article and Find Full Text PDFA kind of hybrid multilayer film based on mercaptobenzoic acid-capped Au nanoparticles (MBA-Au-NPs) and photoreactive nitrodiazoresin (NDR) has been fabricated via electrostatic self-assembly. Upon exposure to UV light, the initial ionic bonds between the layers of the film convert into covalent bonds and the film stability toward polar solvents, salt, or surfactant solutions increases significantly. The micropatterned NDR/MBA-Au-NP film with the covalently linked architecture was formed by selecting exposure of the film through a photomask and later developed in sodium dodecyl sulfate (SDS) aqueous solution.
View Article and Find Full Text PDFJ Colloid Interface Sci
October 2004
In this paper, we reported the preparation of macroporous Au materials using organic colloidal crystals as templates and their catalytic activity for electroless copper deposition. The poly(styrene-methyl methacrylate-acrylic acid) (P(St-MMA-AA)) copolymer colloids were deposited in an orderly manner onto the silicon surface, together with the infiltration of the Au nanoparticles into the interspaces of the colloids. The formed hybrid colloidal crystal subsequently was sintered at approximately 550 degrees C to remove the organic components fully to obtain a macroporous Au framework with three-dimensional ordered porous structure.
View Article and Find Full Text PDFA stairlike colloidal crystal thin film composed of poly(styrene-methyl methacrylate-acrylic acid) (P(St-MMA-AA)) monodispersed colloids was fabricated on an inclined silicon substrate. Different bright colors were observed on the various parts of the film with different layers as white light irradiated perpendicularly on it. The relationship between the colors and layers of the film was investigated and discussed according to the principle of thin film interference.
View Article and Find Full Text PDFA micropatterned multilayer film, which was fabricated from layer-by-layer electrostatic self-assembly of nitrodiazoresin (NDR)/poly(acrylic acid) (PAA) followed by photolithography, was utilized as a structured template for the biomimetic mineralization of calcium carbonate. Micropatterned CaCO3 films consisting of regularly aligned calcite crystals oriented in the <104> direction were selectively deposited on the patterned NDR/PAA multilayer film.
View Article and Find Full Text PDFJ Colloid Interface Sci
September 2004
Micropatterned cross-linked film making up a temperature-responsive component has been fabricated through the following two steps: layer-by-layer electrostatic assembly of photosensitive nitrodiazoresin (NDR) and a thermosensitive copolymer of poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPA-AA)), and subsequent selective exposure to UV light through a photomask followed with development in sodium dodecyl sulfate (SDS) aqueous solution. The irradiated regions of the film are retained due to the formed covalently linked structure, whereas the unirradiated parts of the film are removed fully from the substrate in SDS solution. The well-defined micropatterns were characterized with field-emission scanning electron spectroscopy (FE-SEM) and atomic force microscopy (AFM).
View Article and Find Full Text PDFJ Colloid Interface Sci
July 2003
A covalently attached sandwich structure between layers and particles has been fabricated from z.sbnd;COOH-containing copolymer latex particles and z.sbnd;N(2)(+)-containing polymers by self-assembly combined with a UV irradiation technique.
View Article and Find Full Text PDFCovalently linked Au-NPs micropatterns have been successfully fabricated from the self-assembly film composed of 4-mercaptophenol-capped Au nanoparticles (Au-NPs) and -N2+ containing polymers of nitro-diazoresin (NDR) by selective exposure to UV light and development in sodium dodecyl sulfate (SDS) aqueous solution. The resultant well-defined micropatterns were characterized with AFM and XPS.
View Article and Find Full Text PDFJ Colloid Interface Sci
June 2001
The self-assembly film fabricated via the layer-by-layer technique was studied by the dynamic contact angle (DCA) method (wilhelmy plate method). The used polyelectrolytes are poly(diallyl-dimethylammonium chloride) (PDDA), poly(etheleneimine) (PEI), diphenylamine-4-diazonium-formaldehyde resin (DR), 2-nitro-N-methyl-4-diazonium-formaldehyde resin (NDR), and poly(sodium-p-styrenesulfonate) (PSS). For the self-assembly systems of PDDA/PSS, PEI/PSS, DR/PSS, and NDR/PSS, their individual contact angle fluctuates regularly with the fabrication of each layer, while the magnitude of different systems' contact angle depends on the participant polycation.
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