1215 results about "Carboxylation" patented technology

Hemostatic agents and devices are made from oxidized cellulose fiber, the oxidized cellulose having a carboxylation content increased by the action of nitrogen dioxide on virgin cellulose fiber. A composition may be incorporated into the oxidized cellulose fiber to cause a pharmacological effect on a wound to which the hemostatic agents and devices are applied. When applied, the oxidized cellulose fiber causes blood emanating from the wound to clot. The oxidized cellulose fiber can either be resorbed into the wound or removed from the wound after healing. A hemostatic bandage includes a pad of unwoven oxidized cellulose fibers mounted on a substrate. Methods of arresting a flow of blood emanating from a wound using such devices are also disclosed. Methods of fabricating oxidized cellulose are also disclosed.

The invention provides a method for preparing fibrilia carboxylation cellulose nanowhiskers, which is characterized by comprising the following steps: soaking fibrilia powder in sodium hydroxide for processing, then processing the fibrilia powder by a former treating agent and taking out the fibrilia powder to be dried in a vacuum oven to obtain preprocessed fibrilia powder; and placing the preprocessed fibrilia powder in a TEMPO oxidation system for catalytic oxidation to obtain a stable cellulose nanowhiskers suspending liquid after mechanical processing and freeze drying the suspending liquid to obtain the fibrilia carboxylation cellulose nanowhiskers having grain diameters of 3-10 nm. According to the invention, fibrilia carboxylation and nano fibrillation are realized and surfaces of prepared nanocrystalline celluloses have carboxyl functional groups, thus the surfaces generate negative charges, electrostatic repulsion among the negative charges can avoid the reunion of nanoparticles, so that the nanocrystalline celluloses can be well dispersed in water and the obtained nanocrystalline celluloses have excellent uniformity of grain sizes.

The invention relates to a preparation method of a graphene modified nylon 6 fiber and belongs to the technical field of a functional fiber material. The preparation method comprises the following steps of: carrying out carboxylation and acylating chlorination treatment on graphene; then carrying out diamine treatment to obtain graphene oxide with an active amino on the surface; carrying out polymerization reaction by utilizing the aminated graphene and caprolactam through an initiator 6-aminocaproic acid to prepare a modified nylon 6 melt of the graphene; and carrying out spinning and stretching through a fusion and spinning process to obtain the graphene modified nylon 6 fiber. The technical scheme of the invention utilizes aminated graphene enhanced 6 to improve the interface bonding strength with a base resin, so as to be good for improving the whole performance of the graphene modified nylon 6 fiber. A fiber material prepared by the preparation method provided by the invention can be widely applied to the technical fields of aerospace, cars and ships, communication and transportation, mechano-electronics and the like.

The invention relates to a crude oil demulsifier, and discloses a natural polysaccharide macromolecule-modified crude oil demulsifier. The demulsifier is prepared by adopting the following operation steps: (1) conducting halogenation modification, carboxylation modification, amination modification, formylation modification, or isocyanic acid esterification modification on polyethylene glycol monomethyl ether; (2) preparing glycidyl dimethyl alkyl ammonium chloride; (3) preparing quaternized polysaccharide; and (4) reacting the modified polyethylene glycol monomethyl ether with quaternized polysaccharide to obtain a product, namely the natural polysaccharide macromolecule-modified crude oil demulsifier. According to the crude oil demulsifier, as the raw material, the natural polysaccharide macromolecule compound has multiple advantages of being wide in source, natural, non-toxic, sustainable, good in usage safety and the like; and the prepared demulsifier has good demulsifying and dewatering effects; in addition, the molecules of the demulsifier contain a great deal of groups of hydroxyl and the like, which have certain chelating capability to metal ions, thus being capable of removing a certain amount of metal ions while demulsifying.

The invention belongs to the technical field of friction material, and in particular relates to a graphene-nano polytetrafluoroethylene composite filler with a function of reducing friction, as well as a preparation method and the application of the composite filler. The composite filler comprises the following main components in parts by weight: 1 part of modified graphene and 1-20 parts of modified nano polytetrafluoroethylene; the preparation method of the composite filler comprises the following steps: separately reacting graphene and nano polytetrafluoroethylene with amination reagent and carboxylation reagent to obtain the modified graphene and the modified nano polytetrafluoroethylene; carrying condensation reaction so that the modified graphene and the modified nano polytetrafluoroethylene are connected with each other by a covalent bond to obtain the graphene-nano polytetrafluoroethylene composite filler. The function of friction reduction of the graphene and the function of lubrication of the nano polytetrafluoroethylene are utilized at the same time; after the composite filler is added to a polymer material, the friction coefficient and the wear rate of the material can be reduced, and the mechanical property of the material can be improved.

The invention relates to a method for modifying aramid fiber by using carbon nano tubes, which comprises the following steps of: selecting an epoxy resin/ aramid fiber composite material as a research object, selecting the carbon nano tubes as a surface modification material, forming free amino groups in a certain ratio on the aramid fiber by a chemical modification method, soaking the aramid fiber into N-methylpyrrolidone solution (NMP), and reacting the solution and the surface carboxylation carbon nano tubes with the aid of ultrasonic, wherein part of carbon nano tubes enter the interior of Kevlar fiber, and the other part of carbon nano tubes are fixed on the surface of the fiber through amido bonds formed by the carbon nano tubes and amino, thus, a aramid fiber complex inside and outside which the carbon nano tubes are doped is formed. Single fiber tensile test results and single fiber pull-out test results show that the mechanical property of the modified aramid fiber and the interface bonding strength with the epoxy resin are improved.

The invention discloses a preparation method of carbon nano tube/polyaniline netty compound material, which comprises the steps of: A. implementing carboxylation of the carbon nano tube; B. implementing acyl chlorination of the carbon nano tube; C. implementing amidation of the carbon nano tube to obtain the carbon nano tube with positioned graft aniline monomer; and D. implementing electrochemical deposition and aggregation: preparing 200mL of aniline liquor with the concentration of 0.1 to 0.5 mol. L<-1>, adding the aniline liquor into an electrolyte liquor, then adding 0.12g of the mixed liquor of the carbon nano tube obtained in the step C, and then implementing electrochemical deposition to obtain the carbon nano tube/polyaniline netty compound material after nitrogen is introduced infor 30 min. When the carbon nano tube/polyaniline netty compound material prepared by using the method is used as an energy storage material, the specific capacity is large and the circulating stability is good; therefore, the carbon nano tube/polyaniline netty compound material is particularly applicable to preparing the electrode materials of energy storage components such as super capacitors,etc; and the method can easily prepare the carbon nano tube/polyaniline netty compound materials with different thicknesses and different layers.

The invention relates to a preparation method of a grafting amphoteric chitosan flocculant, comprising the following steps: carrying out graft copolymerization between carboxymethyl chitosan and polyacrylamide to obtain the grafting amphoteric chitosan flocculant, wherein the substituted ratio of a carboxyl group is 5%-90%, and the mass of the polyacrylamide is 40%-80% of the grafting amphoteric chitosan flocculant. The carboxymethyl chitosan can be obtained by separation after carboxylation reaction between chitosan and chloroacetic acid. The chitosan can adopt various commercially available products, and preferably, molecular weight of the chitosan is not less than 50,000, more preferably 750,000-850,000. The carboxymethyl chitosan grafting polyacrylamide flocculant prepared by the method of the invention improves water solubility of the chitosan, is applicable to treating water with different electric charges, and has good salt tolerance; and the flocculant can be also widely applied to an acid medium and an alkaline medium, and has wide adaptability to the pH value range.

The invention relates to a preparation method of multidimensional hybrid composite of glass fibre/ grapheme-carbon nano tube/ epoxy resin. In the method, after grapheme-carbon nano tube network structure is subjected to surface carboxylation, diamine or polyamine is introduced on the grapheme-carbon nano tube network structure; the grapheme-carbon nano tube connected with the amino is modified by micromolecule aromatic polybasic anhydride compound to prepare the carbon nano tube carried with an anhydride group; the grapheme-carbon nano tube is dispersed in the epoxy resin matrix by ultrasonic oscillation and high-speed stirring; organic acid anhydride curing agent is adopted for curing; and the obtained epoxy resin polymer containing the grapheme-carbon nano tube serves as the matrix to be compounded with glass fiber processed by silane coupling agent to form a multifunctional hybrid composite structure connected by covalent bonds. The multidimensional hybrid composite is convenient to prepare, the application range of the glass fiber, the grapheme, the carbon nano tube and the epoxy resin is widened, so that the hybrid composite can be widely applied on the aspects of aerospace, traffic transportation, electronic industry, civil facilities, building, chemical engineering and the like, can be industrially produced on a large scale, has low cost and is friendly to environment.

The invention discloses a preparation method of a polyamide composite nanofiltration membrane containing a modified carbon nano tube, wherein the preparation method comprises the following steps: applying a mixed acid H2SO4/HNO3 to process the carbon nano tube so as to prepare a carboxylation nano tube, taking the carboxylation nano tube and methyl methacrylate as raw materials and grafting polymethyl methacrylate with a micro-emulsion polymerization method under effects of a surfactant and AIBN in order to implement lipophilic non-polar treatment to a multi-wall carbon nano tube to obtain PMMA-MWNTs. The membrane prepared in the invention has the advantages of high water flux, high desalinization rate, simple preparation operation and mild reaction conditions and can be applied for industrial production.

The invention discloses a pH-responsive anti-tumor drug carrier material and a preparation and application of the pH-responsive anti-tumor drug carrier material. The preparation method comprises the following steps that (1) gold nanoparticles wrapped by mesoporous silica are prepared, and the gold nanoparticles comprise gold nanospheres or gold nanorods; (2) gold nanoparticles wrapped by carboxylation mesoporous silica are prepared; (3) water-soluble zinc oxide quantum dots are prepared; and (4) the pH-responsive anti-tumor drug carrier material is prepared. According to the pH-responsive anti-tumor drug carrier material and the preparation and application of the pH-responsive anti-tumor drug carrier material, the whole technological process design of the preparation method, the parameter conditions adopted by the reaction steps and the like are optimized, and the existing problems that drug releasing is uncontrollable, the drug loading capacity is low, and side effects are prone to being caused when the gold nanoparticles wrapped by the mesoporous silica serve as a drug carrier can be effectively solved.

The invention discloses a method for preparing carboxymethyl chitosan. The method comprises the following steps of by using chitin as a material, alkalifying the chitin, carrying out deacetylation reaction by using a cooling-heating alternative method to produce chitosan sodium salt; and then, carrying out carboxylation under an alkaline condition to obtain a carboxymethyl chitosan product. The method disclosed by the invention is simple in process and easy to control, so that a chain scission phenomenon appearing due to long-term high temperature reaction during deacetylation reaction of a chitosan molecular chain is avoided, thereby obtaining carboxymethyl chitosan which is high in viscosity, high in degree of substitution and better in water solubility; moreover, the method is suitable for large-scale industrial production.

The invention relates to a method for preparing magnetic silicon dioxide microspheres with the surfaces chelated with metal ions; the method of the inventioncomprises the following steps of preparation of the magnetic silicon dioxide microspheres, epoxidation of the magnetic silicon dioxide microspheres, carboxylation of the magnetic silicon dioxide microspheres and chelation technique of metal ions. Compared with the existing preparing method, the method of the invention has the advantages of reasonable design, simple operation and large amount of chelation of metal, etc. The magnetic silicon dioxide microspheres with the surfaces chelated with the metal ions, which are prepared by adopting the method, contain cobalt ions, have stronger bonding force with the modified microspheres so as to lead the cobalt ions to be not easy to leak out, and have higher selectivity and proper bonding strength with histidine on the protein, thus leading the magnetic silicon dioxide microspheres with the surfaces chelated with the metal ions to have high selectivity to hexameric histidine tag protein, and being easy to realize the separation and the purification of the target protein; the magnetic silicon dioxide microspheres with the surfaces chelated with the metal ions, which are prepared by adopting the method, can be used for separating the hexameric histidine tag protein.

The invention belongs to the nano-material technical sphere, especially it relates to a method for preparation of triplefunction carbon nano-tube used in epoxide resin nano-recombination. The invention adopts molecular design conception, namely that after the suface-definite quantity carboxylation and chloridization, the long-chain diamine with a character construction is introduced into the purified carbon nano-tube, then the grafted carbon nano-tube with a quantitative active amidol on surface is obtained. Making use of the chemical attraction of the construction to the base resin and the chemical reaction with the base resin, we can better the dispersibility of the carbon nano-tube and improve the basal binding strength with the base resin. At the same time the carbon nano-tube can exert multiple functions, for example, it is easy to disperse, its interfacial caking capacity is fine, and it is reinforced and solidified. So the obtained triplefunction carbon nano-tube used in epoxide resin nano-recombination is good to improve the bulk property of the carbon nano-tube/epoxide resin composite and is suitable for industrial use for carbon nano-tube.

The present invention relates to methods and tools for producing large quantities of gamma-carboxylated protein comprising: (i) culturing a cell adapted to express a protein which requires gamma-carboxylation and γ-glutamyl carboxylase in a ratio of at least 10:1, under conditions suitable for expression of both proteins, and (ii) isolating gamma-carboxylated protein.

The invention discloses a producing method for carbon nano tube/epoxide resin compound material, including steps of: processing the native carbon in the flowing bed jet mill, carboxylation, introducing polyatomic alicyclic amine with a flexibility structure on the carbon nano tube surface. The carbon nano tube/epoxide resin compound material is produced by mixing the epoxide resin and carbon nano tube by hot melt method, high speed stirring, ultrasonic treatment, then adding aromatic amine for solidification moulding. The advantages of the invention is that grafting polyatomic alicyclic amine on the carbon nano tube surface improves the surface function efficiency of the carbon nano tube, reduces the surface energy of the carbon nano tube, decreases the self-aggregation of the carbon nano tube, promotes both affinity and achieves organic connection of the carbon nano tube and epoxide resin by resin chemical reaction. The invention has a simple craft, a qualified mechanical property of obtained compound material, and an ulterior industry application convenient for the carbon nano tube.

The invention provides a preparation method of an esterified macromer for a polycarboxylate water-reducer. The preparation method comprises the following steps: performing carboxylation reaction on terminal hydroxyl of mono-hydroxyl-terminated polyether to obtain a polyether intermediate with carboxylate as a terminal group; performing esterification reaction on the polyether intermediate with carboxylate as the terminal group to obtain the esterified macromer for the polycarboxylate water-reducer. According to the method, an organic solvent does not need to be used as a water-carrying agent, the reaction condition is mild, side reactions are few, and the polymerizable activity of the obtained esterified macromer is high; the method is an efficient and environment-friendly novel method for preparing the esterified macromer for the polycarboxylate water-reducer.

The invention discloses a piece of self-supported reduced graphene oxide paper and a preparation method thereof. The preparation method comprises the following steps: reducing a graphene oxide solution, performing carboxylation treatment on the reduced graphene oxide, preparing carboxylated reduced graphene oxide solid powder, and making the self-supported reduced graphene oxide paper. The preparation method is simple and feasible, and can be used for on-scale preparation. The self-supported reduced graphene oxide paper prepared by using the preparation method is relatively good in mechanical property, high in purity, uniform, flat, controllable in thickness and shape, and good in development prospect in fields such as functional composite materials and super capacitors.

The invention discloses a method for preparing nitrogen and sulfur codoped porous carbon prepared from direct coal liquefaction heavy organic matter. The method includes the following steps that 1, the direct coal liquefaction heavy organic matter is ground into powder, and a first hydrophilic product is obtained through hydroxylation, or carboxylation or sulfonation; 2, the first product react with a mixture of formaldehyde and thiourea to obtain a second product containing nitrogen and sulfur; 3, the second product is mechanically mixed with a magnesium source by a certain ratio, the mixture is placed in a carbonization furnace to be carbonized, and a magnesium oxide and nitrogen and sulfur codoped porous carbon mixture is obtained; magnesium oxide is removed through pickling to obtain the nitrogen and sulfur codoped porous carbon. The purpose is to broaden the selection range of nitrogen-containing species, sulfur-containing species and carbon-containing precursors in the preparing process of the nitrogen and sulfur codoped porous carbon, and a new path is found for using coal liquefaction residues. The prepared nitrogen and sulfur codoped porous carbon has excellent electrochemical performance and is high-performance electrode material of a supercapacitor and an oxygen reduction reaction catalyst.

The invention discloses a preparation method of 3,6-dichloro-2-hydroxybenzoic acid, which sequentially comprises the following steps: 1) salifying 2,5-dichlorophenol; 2) carboxylation: transferring the 2,5-dichlorophenate solution into a high-pressure reaction kettle, adding a cocatalyst, and introducing CO2 to carry out high-pressure carboxylation reaction to obtain the reaction product containing 3,6-dichloro-2-hydroxybenzoate, wherein the cocatalyst is composed of potassium carbonate and activated carbon; 3) refinement: after cooling the reaction product containing 3,6-dichloro-2-hydroxybenzoate obtained in the step 2) to room temperature, adding an alkali solution, regulating the pH value to 11-13, uniformly stirring, filtering to recover activated carbon, stratifying the filtrate, and taking the water phase; and adding an acid solution into the water phase, regulating the pH value to 1-3, carrying out vapor distillation to recover the 2,5-dichlorophenol, cooling to crystallize, carrying out vacuum filtration, and drying to obtain the 3,6-dichloro-2-hydroxybenzoic acid.