416 results about "Silica nanoparticles" patented technology

The invention relates to a nanoparticle-added composite foam system used for an oil and gas field and a preparation method thereof. The composite foam system comprises components of, by mass, 0.3 to 0.5 parts of an anionic surfactant, 1 to 1.5 parts of modified silica nanoparticles, 0.03 to 2.3 parts of counter-ion salt, and 100 parts of water. The method comprises mixing the abovementioned components according to ratio, stirring by using a magnetic stirrer, standing, and then rapidly stirring to form well stable foam using a Waring Blender way. According to the composite foam system, the produced foam has a longer half life than that of foam stabilized by ordinary surfactant, and a larger start-foaming volume than that generated by adding a foam stabilizer The system has advantages of simple formula and preparation technology and good salt tolerance and temperature tolerance, can adapt to complex oil reservoir condition underground, does not pollute stratum, is capable of effectively blocking large channels and improving sweeping efficiency, and thus has good application prospects in oil field exploitation, especially in foam displacement.

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 belongs to the field of lithium batteries, and relates to an inorganic/organic composite porous lithium battery diaphragm and a preparation method thereof. The inorganic/organic composite porous lithium battery diaphragm comprises a base material layer and an inorganic/organic composite porous diaphragm layer arranged on the surface of the base material layer, wherein the base material layer adopts polypropylene non-woven fabrics; the inorganic/organic composite porous diaphragm layer adopts a polyvinylidene fluoride- hexafluoropropylene multipolymer containing inorganic nano grains and hydrophilizing agents; and the inorganic nano grains are silicon dioxide nano grains or coupling agent improved silicon dioxide nano grains. The inorganic/organic composite porous lithium battery diaphragm provided by the invention has the advantages that the production cost of the lithium battery diaphragm is lowered while high ion-conductivity, excellent electrochemical performance, high mechanical strength and low thermal shrinking percentage are ensured.

Provided are amphiphobic block copolymers, methods for preparing amphiphobic block copolymers, and applications thereof. Amphiphobic block copolymers can be used to prepare amphiphobic coatings on material surfaces, such as glass, printing paper or fabric. Amphiphobic block copolymers can also be used to coat particles, e.g., silica nanoparticles, which are then used to coat material surfaces. Such coated particles and uses thereof are also provided herein.

The present invention pertains to a method for preparation of superhydrophobic timber on the basis of a sol-gel method, and the method is as follows: (1), silica sol synthesis, to be more specific, materials are prepared in the volume ratio of ammonia to anhydrous ethanol to ethyl orthosilicate of 1:15 to 17:1; (2), hydrophobic modification of monodispersed nano silica sol, to be more specific, hexadecyl trimethoxysilane, or triethoxysilane-1H, 1H, 2H, 2H-heptadecafluorodecyl silane is used for hydrophobic modification of the synthesized monodispersed nano silica sol, and the hydrophobic agent promotes mutual aggregation of nanoparticles to promote the formation of aggregates of silica nanoparticles; and (3) timber coating processing, to be more specific, the timber surface is coated with the hydrophobically modified silica sol solution by dipping or spraying process. Contact angles of the processed timber surface and water droplets are greater than 150 degrees, roll angles are less than 10 degrees, and a superhydrophobic film has good resistance to acid and alkali erosion and stability in high-humidity environment. The method is simple in operation, less demanding on equipment, and capable of scale production, and has wide market prospects.

The invention discloses super-wear-resisting super-hydrophobic coating and a preparation method thereof; the coating is prepared by: stirring well and dispersing non-solvent aliphatic polyether polyol resin, micro-powder granules, 2,4-toluenediisocyanate and fumed silica nanoparticles, applying to the surface of a substrate by brushing or spraying technology, roughing the surface after full curing, spraying, brushing or dipping super-hydrophobic nano coating to the surface of resin primer, and naturally drying. The super-wear-resisting super-hydrophobic coating and the preparation method thereof have the advantages that the equipment and process are simple, operating is easy, and the cost is low; and have industrial scale production prospect. The super-wear-resisting super-hydrophobic coating prepared herein features high bonding force, high hardness and the like, is capable of bearing destruction from external forces such as high pressure friction, and is applicable to the fields, such as building, shipping, naval craft, aircrafts, automobiles, high-speed railway, and wind generators.

Additives comprising dispersed silica nanoparticles are disclosed. The silica nanoparticles are dispersed in an aminoplast, such as a modified aminoplast formed from the reaction between an aminoplast, a modifying component, and optionally a siloxane. The resulting additives can be added to coating compositions to provide improved mar and/or scratch resistance.

The invention belongs to the field of anticorrosion materials, and relates to a green and environment-friendly method for protecting metal from corroding, which can particularly control metal corrosion for long time effectively, and play a role in self-repairing the metal surface to a certain extent. The method is characterized in that an inhibitor molecule and polyelectrolyte are alternately deposited on the surface of a silicon dioxide nano-particle through green environment-friendly type metal inhibitor micromolecules and polyelectrolyte by adopting layer-by-layer self-assembly technology and utilizing the penetrating controllability of a polyelectrolyte self-assembly membrane so as to prepare a functional nano-particle with the inhibitor and the polyelectrolyte self-assembly composite membrane which are coated on the surface; and the prepared functional nano-particle is mixed with sol-gel to prepare the functional sol-gel membrane coated on the metal surface to be protected. The coating has the function of metal surface self-repairing, and ensures that the inhibitor molecules released by the functional membrane are adsorbed on the metal surface to reform a protecting membrane in a coating damaged microsection to play a certain role in self repairing. The method is applicable to corrosion protection of various metals.

A gold nanoparticle-based assay for the detection of a target molecule, such as Hepatitis C Virus (HCV) RNA in serum samples, that uses positively charged gold nanoparticles (AuNPs) in solution based format. The assay has been tested on 74 serum clinical samples suspected of containing HCV RNA, with 48 and 38 positive and negative samples respectively. The developed assay has a specificity and sensitivity of 96.5% and 92.6% respectively. The results obtained were confirmed by Real-Time PCR, and a concordance of 100% for the negative samples and 89% for the positive samples has been obtained between the Real-Time PCR and the developed AuNPs based assay. Also, a purification method for the HCV RNA has been developed using HCV RNA specific probe conjugated to homemade silica nanoparticles. These silica nanoparticles have been synthesized by modified Stober method. This purification method enhanced the specificity of the developed AuNPs assay. The method can detect a target molecule, such as HCV RNA in serum, by employing modified silica nanoparticles to capture the target from a biological sample followed by detection of the captured target molecule using positively charged AuNPs. The assay is simple, cheap, sensitive and specific. Another aspect of the invention is anisotropic silver nanoparticles and methods of their use.

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.

Disclosed are herein functionalized silica nanoparticles having polyethylene glycol linkages and a production method thereof. More specifically, example embodiments relate to functionalized silica nanoparticles that avoid of aggregation nanoparticles via introduction of PEG linkages onto the nanoparticles and have high reactivity via introduction of PEG which links a ligand to a target cell, and a production method thereof.

The invention relates to a preparation method of a two-dimensional porous silicon dioxide nanosheet. In the method of the present invention, firstly, graphene oxide, tetraethyl orthosilicate, ammonia water, and a mixed solvent are mixed and then ultrasonically stirred to form a nano-silica-loaded graphene oxide solution, and then the nano-silica-loaded graphene oxide solution is centrifuged , Dissolve in water after washing to form a graphene oxide aqueous solution supported by nano-silica, freeze into a solid state and dry to form a flocculent silica-loaded graphene oxide hybrid; the silica-loaded graphene oxide hybrid The compound is calcined at 400-800° C. for 2-8 hours to obtain two-dimensional porous silicon dioxide nanosheets. The method of the invention has no pollution to the environment, is energy-saving and environment-friendly, has simple and easy operation, strong controllability, high repeatability, high yield, is green and environment-friendly, and can realize large-scale production.

The present invention is to provide an epoxy resin composition uniformly containing a large amount of inorganic fillers, excellent in heat resistance and flame resistance, and having good impregnation into a base material, and a prepreg using the epoxy resin composition, having good tackiness, and being easy in handling. Furthermore, it is to provide a printed wiring board using a metal-clad laminate formed using the prepreg and/or the prepreg or the epoxy resin composition, capable of easily conducting an ENEPIG process, and a semiconductor device using the printed wiring board, excellent in performances. An epoxy resin composition comprises a solid epoxy resin, a silica nanoparticle having an average particle diameter of 1 nm or more and 100 nm or less, and a silica particle having an average particle diameter larger than that of the silica nanoparticle, in the range of 0.1 μm or more and 5.0 μm or less.

The invention relates to a contact release capsule comprising a particle, a chemical payload, and a polymer coating, wherein the particle is impregnated with the chemical payload, and the chemical payload is held inside the particle by the polymer coating until the contact release capsule contacts a surface and a shearing force removes the polymer coating allowing the chemical payload to release outside the particle. The contact release capsule is useful in chemical mechanical planarization slurries. Particularly, the contact release capsule may comprise a glycine impregnated silica nanoparticle coated with a polymer, wherein the contact release capsule is dispersed in an aqueous solution and used in the copper chemical mechanical planarization process. Use of the contact release capsule in a slurry for copper chemical mechanical planarization may significantly improve planarization efficiency, decrease unwanted etching and corrosion, and improve dispersion stability.

A substrate with a superhydrophobic coating, wherein the superhydrophobic coating includes a binding layer disposed on the substrate, and a hydrophobic layer disposed on the binding layer, wherein the hydrophobic layer includes perfluoroalkyl-functionalized silica nanoparticles, and a method of fabricating the substrate with the superhydrophobic coating. Various combinations of embodiments of the substrate with the superhydrophobic coating and the method of fabricating thereof are provided.

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.

Disclosed are high surface area nanoparticles that have a fibrous morphology. The nanoparticles have a plurality of fibers, wherein each fiber is in contact with one other fiber and each fiber has a length of between about 1 nm and about 5000 nm. Also disclosed are applications of the nanoparticles of the present invention, and methods of fabrication of the nanoparticles of the present invention.

The invention discloses a method capable of quantitatively detecting surface enhanced Raman spectroscopy (SERS) of polychlorinated biphenyl. The method comprises the following steps: preparing uniform gold-coated silica nanoparticles, and fixing nanoparticles in a core-shell structure on a quartz glass piece to form an SERS substrate by utilizing a coupling agent; connecting an aptamer of a printed circuit board (PCB) with a thiol at one end, and covalently connecting the aptamer of the PCB to the surface of a gold shell layer of the nanoparticles through a thiol; soaking the prepared SERS substrate in a PCB-containing solution, taking the SERS substrate out after sufficient time, cleaning by using deionized water, and performing Raman spectrum measurement. The prepared gold-coated silica nanoparticles are attractive in appearance and high in particle size uniformity, plasma resonance occurs at 750nm, and a strong SERS enhancement effect is achieved under excitation of 785nm<-1> laser.