464 results about "Silica nanoparticle" patented technology

A coating composition is provided comprising a) an aqueous dispersion, having a pH of less than 7.5, of silica nanoparticles having average particle diameters of 40 nanometers or less, b) an alkoxysilane oligomer; c) a silane coupling agent, and d) optionally a metal β-diketone complexing agent. The compositions may be used to prepare coated articles wherein the coating is substantially uniform in thickness, durably adheres to the substrate, and provides hydrophilic and/or antireflection surface properties to the substrate.

The present invention discloses a process for making rare earth (RE) doped optical fibre by using RE oxide coated silica nanoparticles as the precursor materia, more particularly the method of the present invention involves preparation of stable dispersions (sol) of RE oxide coated silica nanoparticles at ambient temperature and applying a thin coating on the inner surface of silica glass tube following dip coating technique or any other conventional methods, of the said silica sol containing suitable dopants selected from Ge, Al, P, etc., the coated tubes were further processed into optical preforms by following MCVD technique and fiberised in desired configuration, the novelty lies in eliminating the step of the formation of porous soot layer at high temperature by CVD process inside a fused silica glass tube for formation of the core and also in the elemination of the incorporation of the rare earth ions into the porous soot layer following the solution doping technique or other conventional methods, the direct addition of RE oxides in the sol eliminates the formation of microcrystalites and clusters of rare earth ions and prevents change in composition including variation of RE concentration in the core which results in increase in the reproducibility and reliability of the process to a great extent, further the addition of Ge(OET)4 at ambient temperature in the silica sol reduces the quantity of GeCl4 which is required at high temperature to achieve the desired Numerical Aperture.

The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.

The invention discloses a silica nanoparticle brick array polarizing beam splitter, and belongs to the field of micro-nano optics and polarizing optics. The silica nanoparticle brick array polarizing beam splitter comprises a transparent substrate and silica nanoparticle brick arrays evenly distributed on the transparent substrate. Silica nanoparticle bricks are cuboid. The arrangement directions of the silica nanoparticle bricks are the same. When incident light perpendicularly enters the silica nanoparticle brick array polarizing beam splitter, light in the polarization direction along long edges and short edges of the silica nanoparticle bricks is reflected and transmitted. The silica nanoparticle brick array polarizing beam splitter can enable one kind of linearly polarized light to be fully transmitted and the other kind of linearly polarized light to be fully reflected, wherein the two kinds of linearly polarized light are perpendicular to each other in the polarization direction. Accordingly, light in the two polarization states is completely separated, and meanwhile the direction of an optical axis is not changed. The silica nanoparticle brick array polarizing beam splitter can adopt a manufacturing method of a binary optical device, is easily copied and produced on a large scale, and has the advantages of being good in beam splitting effect, small in size, low in weight, compact in structure, easy to integrate and capable of conforming to the development trend of the optical element.

the invention discloses a fluoride modified organic silicon nanometer paint, which consists of solvent and active component, wherein the active component is fluoride modified organic silicon nanometer particle, whose reacting raw material contains silicate ester, alkyl silane and fluoride modified alkyl silane according to 8-20: 0.5-1.5: 1. the preparing method comprises the following steps: first, preparing silica nanometer particle through hydrolyzing silicate ester; second, proceeding surface modifying through silica nanometer particle to prepare the product.

The invention discloses a preparation method of an efficient electrostatic spinning oil-water separation fiber membrane. The preparation method includes the steps that polyamic acid (PPA) is synthesized, a PPA nanofiber membrane is prepared in an electrospinning mode, and the PPA nanofiber membrane is imidized into a polyimide membrane (PI); a cellulose acetate (CA) nanofiber membrane is prepared; coaxial electrospinning is carried out on CA-PAA, and a product is imidized into CA-PI; benzoxazine monomers (BAF-tfa) are synthesized; in-situ immobilization is performed on the CA, PI and CA-PI nanofiber membranes with BAF-tfa and BAF-tfa/silica nanoparticles (SiO2NPs); an oil-water separation experiment is carried out. The preparation method has the advantages that by carrying out surface modification on the fiber membranes, the CA-PI nanofiber membrane which is biodegradable, low in cost, large in oil-water separation flow and high in separation efficiency is obtained; the high-performance membrane material has broad application prospects in oil-water separation, sewage treatment and deepwater oil leak.

The invention relates to one magnetic nuclear and earth silicon and metal oxidation three nuclear shell structure nanometer particle and its process method, which uses magnetic nanometer particle as nuclear with diameter of 2 to 5 nm and processes earth silicon nanometer particles with diameter of 10 to 100nm and uses metal alkoxy compound in ethanol system and covers one layer of metal oxidation on earth silicon surface to form three-fold nuclear shell structure of the compound.

The invention specifically relates to a core-shell zinc oxide-silica nanoparticle, and a preparation method and application thereof, belonging to the technical field of nano-materials. The method comprises the following steps: subjecting lithium hydroxide and zinc methacrylate to hydrolysis at room temperature to produce luminous ZnO nanoparticles, adding siloxane monomers containing double bonds and azodiisobutyronitrile, carrying out heating to initiate polymerization so as to form a single organosilicon layer on the surface of the ZnO nanoparticles, then adding other siloxane and ammonia water, and carrying out hydrolysis at room temperature to form a silicon dioxide layer so as to prepare the core-shell zinc oxide-silica nanoparticles. The core of a core-shell zinc oxide-silica nanoparticle is a single zinc oxide luminous quantum dot and has a diameter of 2.7 to 4.6 nm; the shell of the nanoparticle is a thin silica layer; and the core-shell zinc oxide-silica nanoparticle is safe and nontoxic, has high quantum efficiency, stably emits light under continuous UV excitation in cells, can be used for preparing fluorescent labels for biological cells and is especially applicable to preparation of fluorescent labels for cervical carcinoma cells.

Provided is a prepreg which can accommodate a thickness reduction and in which different applications, functions, performances, characteristics, or the like can be imparted respectively to the two surfaces thereof. One of the surfaces of the prepreg has excellent adhesion to a conductor layer, and a fine circuit can be formed thereon. The prepreg comprises a core layer equipped with a fibrous base, a first resin layer, and a second resin layer and further includes a carrier film laminated to the surface of the first resin layer and/or the surface of the second resin layer. The prepreg is characterized in that the first resin layer is a layer comprising a first epoxy resin composition which comprises silica nanoparticles having an average particle diameter of 1-100 nm, a thermoplastic resin, and an epoxy resin, the first resin layer being in contact with the fibrous base or some of the first resin layer having been infiltrated into the fibrous base, and that the second resin layer comprises a second epoxy resin composition which comprises an inorganic filler and an epoxy resin, some of the second resin layer having been infiltrated into the fibrous base.

Fibers, fabrics and textiles in which core-shell silica nanoparticles are incorporated are provided. The fibers, fabrics and textiles can be polymeric materials or natural cellulose-based or protein-based materials in which core-shell silica nanoparticles are incorporated. A variety of polymeric and natural materials can be employed, such as cellulose acetate, nylon, rayon, modacrylic, olefin, acrylic, polyester, polylactic acid, polylactic-co-glycolic acid (PLGA), polyurethane, aramid, wool, cotton, ramie, milk protein, soy protein, bamboo, etc. The core-shell silica nanoparticles can incorporate sensing, magnetic, thermal, electrical, chemical or RFID properties that can be imparted to the materials and that allow the materials to sense one or more conditions of interest, making them ideal for in situ sensing, treatment, or security applications.

A method of bonding a first article to a second article is provided. The method involves the use of a flowable, adhesive composition that contains non-aggregated, surface-modified silica nanoparticles dispersed in an epoxy resin.

The invention provides a copolymer having pH responsiveness; then a mixed solution (sol) is formed from the copolymer and silica nanoparticles, and then pH-responsive two-dimensional thin film material (cotton and filter paper) and a pH-responsive three-dimensional sponge material (polyurethane sponge) are prepared by a simple dip-coating way. The oil-water separation performance of the prepared two-dimensional thin film material and the prepared three-dimensional sponge material can be controlled by adjusting change of the pH. At the pH of 2, the materials show superhydrophilic/underwater superoleophobic performance; at the pH of 12, the materials can have the superhydrophilic/underwater superoleophobic performance converted into superhydrophobic/superoleophilic performance. In addition, the wettability of the materials can be changed in situ under adjustment of the pH. More importantly, the materials not only can separate an oil/water/oil three-phase oil-water mixture, but also can separate water-in-oil, oil-in-water and acid oil-in-water oil-water emulsion, and also can absorb all kinds of oil products.

The invention discloses a chitosan-coated magnetic mesoporous silica core-shell structure nano-particle and a preparation method and application thereof. The preparation method is characterized by comprising the following steps: preparing a ferroferric oxide nano-particle by using a co-precipitation method; preparing a magnetic silica nano-particle by using a sol-gel method, and removing a pore-foaming agent by using an ion exchange method to obtain a magnetic mesoporous silica nano-particle; performing surface treatment on magnetic mesoporous silica by using a silane coupling agent, and then grafting chitosan to obtain a target product. The ferroferric oxide nano-particle is introduced into the obtained product, so that after adsorption is completed, the product can be quickly separated and recycled through an external magnetic field; the product has an excellent adsorption effect on methylene blue.

The invention relates to water-based transparent super-amphiphobic nano-paint and a preparation method and application thereof. Under the room temperature condition, hydrophilic silica nanoparticles and tetraethoxysilane or carbon tetrachloride serve as raw materials to synthesize oily nanoparticles with the concentration of 1-10 mg/mL; the oily nanoparticles and fluorocarbon resin are compounded according to the volume ratio of 1:1, a rotary evaporator is utilized for rotary evaporation for 30-60 min under the condition of a water bath at the temperature of 60-90 DEG C, and high-solid-content oily nano-paint concentrated liquor with the concentration of 20-40 mg/mL is obtained; water and surfactant are added, and the water-based transparent nano-paint with the super-amphiphobic surface is obtained. The prepared paint is soluble in water, the preparation process is simple, and the paint is suitable for large-area spraying, is high in adaptability to a base material and transparency, good in protective performance, environmentally friendly and capable of improving the working environment, and saves energy.

The invention discloses an antireflection film used in the all-angle and wide wavelength range and a preparation method thereof. The film comprises a substrate, a first sol-gel layer, a silica nanoparticle layer and a second sol-gel layer. A first sol-gel film layer is prepared on the substrate by a pulling method, then a silica particle layer is prepared on the surface of the film by a molecularself-assembly technique, and finally a second sol-gel film layer is prepared on the surface of the film layer by the pulling method, wherein, the film on each layer is subjected to heat treatment. Byoptimizing the technological parameters, the film can have the following characteristics: the refractive index in the direction from the substrate to the air decreases progressively, the thickness matches and the surface micro-structure is two-dimensional ordered; therefore, the film realizes the antireflection effect in the all-angle and wide wavelength range and simultaneously has the ability of film forming in large area, the mechanical property and firmness of the whole antireflection film can be effectively improved, and the energy use ratios of the solar cells and the solar collector tubes are increased.

The invention relates to a method for preparing a monodisperse silicon dioxide nanoparticle sol for paint, which comprises the following steps: with tetraethyl orthosilicate as a precursor, preparing the mixture of a nanometer silicon dioxide sol and a surfactant by an ultrasonic means, and with the mixture of the nanometer silicon dioxide sol and the surfactant as a primary component, obtaining a nanometer silicon dioxid organic sol and a hydrosol, which have a uniform dispersion particle size and a small dispersion size. The monodisperse silicon dioxide nanoparticle sol is colorless and transparent, extends a new application scope for the paint and improves the dispersion of nano particles in the paint, thereby improving the performance and the quality of the paint.

The invention provides a preparation method of monodisperse hollow mesoporous silica nanoparticle, and relates to a preparation method of nanoparticle. The invention overcomes the technical problem that the hollow mesoporous silica prepared by the prior art has rough surface, bad sphericity, and inhomogenous dimension. The method includes: dissolving cetyl trimethyl ammonium bromide into ethanol aqueous solution, adding polystyrene microsphere, adding ammonia water, adding dropwise ethyl orthosilicate, performing centrifugation, drying the precipitate, moving the precipitate into a muffle furnace, and calcining the precipitate to obtain the product. The invention provides the preparation method of hollow mesoporous silica nanoparticle having homogeneous dimension, good sphericity, and controllable particle size. Moreover, the method has simple process and low cost, and can improve the application range of the hollow silica greatly. The invention belongs to the field of preparation of silica nanoparticle.

The invention discloses a ratiometric fluorescent probe and a preparation thereof, and an application of the ratiometric fluorescent probe in detection of glutathione. The ratiometric fluorescent probe is prepared through the following steps: with green quantum dots as cores, carrying out embedding in silica nanoparticles, then subjecting the surface of the silica nanoparticles to amination modification, and covalently coupling red quantum dots onto the amination modified surface of the silica nanoparticles so as to obtain the ratiometric fluorescent probe, wherein the green quantum dots are cadmium telluride quantum dots modified by N-acetyl-L-cysteine. According to the invention, a St ber method is utilized to prepare quantum dot embedded silica nanoparticles, so the synthetic method issimple and has less time consumption. The probe provided by the invention has low detection limit and can realize specific detection during detection of GSH; meanwhile, the probe has advantages like simple preparation and good stability, reduces the detection limit of glutathione to 45 nM, and provides convenience for rapid visual detection.

The invention discloses a dual-color fluorescence quantum dot embedded ratiometric probe and a preparation method thereof; the ratiometric probe takes red quantum dots as a core, the red quantum dots are embedded in silica nanoparticles, then the surface of the red quantum dot embedded silica nanoparticles is subjected to sulfhydrylation, then green quantum dots are grown in-situ on the sulfhydrylation silica surface, and composite nanoparticles with dual emission wavelengths are obtained; finally, the surface of the composite nanoparticles with the dual emission wavelengths is coated with a silica nanoparticle layer, and thus the dual-color fluorescence quantum dot embedded ratiometric probe is obtained. The red ray emitted quantum dot embedded silica nanoparticles are prepared by a reverse microemulsion method; compared with a stober method, the silica nanoparticles have better dispersion; moreover, the quantum dots are made into an alkali solution for incubation, the fluorescence properties are improved, and the silica nanoparticles coating the particle surface improve the specificity and stability of the dual-emission fluorescence ratiometric probe.

The present invention is directed to acrylic polymers comprising: (i) hydroxyl functional groups; (ii) polydialkylsiloxane functional groups; and (iii) silica nanoparticles that are chemically bonded to and pendant from the acrylic polymer. The present invention is further directed to curable film-forming compositions comprising acrylic polymers, and to coated substrates comprising the curable film-forming composition applied to at least one surface of the substrates. The present invention is also drawn to methods of mitigating dirt build-up on a substrate, comprising applying to at least a portion of the substrate the curable film-forming composition described above and at least partially curing the curable film-forming composition.

A formulation for the delivery of an anti-inflammatory agent to a subject is described. In one particular application of the invention, the formulation comprises oil-based or aqueous droplets comprising indomethacin (1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1-H-indole-3-acetic acid) or celecoxib (4-[5-(4-methylphenyl)-3-(trifluoromethyl) pyrazol-1-yl] benzenesulfonamide) stabilised by nanoparticles, particularly silica nanoparticles.