53results about How to "Increase the amount of grafting" patented technology

The invention discloses a method for preparing a lubricating coating with strong stability on the surface of a medical polyurethane material, comprising the following steps of: step 1, pretreating the medical polyurethane material so as to obtain positions with proper surface roughness and reaction activity; step 2, putting the polyurethane polymer material pretreated in the step 1 into a gas phase system of reaction solution or solute for grafting reaction; and step 3, cleaning and drying the reaction products from the step 2. The method can be widely used for preparing medical polymer materials and high-lubricity coating materials on the surface of medical instruments.

The invention discloses a method for carrying out real silk fabric anti-crease and antibacterial finishing by virtue of a laccase-TEMPO process. Quinones active groups are generated through catalyzing tyrosine residual groups in real silks by laccase so that chitosan molecules are grafted on the real silks; then 2,2,6,6-tetramethylpiperidine-nitrogen oxide (TEMPO) is added and is used for catalyzing chitosan and tyrosine in the real silks to generate formyl groups, so that the grafting amount and bonding firmness of the chitosan on the real silks are increased, and the real silk fabric anti-crease and antibacterial finishing is realized. The method comprises the following specific steps of: (1) catalytically oxidizing the tyrosine residual groups in the real silks by the laccase; (2) taking the chitosan and the quinones active groups in the real silks to react; (3) catalyzing the real silks by laccase-TEMPO to graft the chitosan; and (4) washing the real silks with water and then treating. Compared with traditional chemical cross-linking-process vacuum fabric anti-crease and antibacterial finishing, the method has the advantages that the grafting efficiency of the chitosan is high, enzyme treatment conditions are moderate, the real silk fabric anti-crease and antibacterial effect is relatively good and the strength of the fabric is improved.

The invention discloses a preparation method of a nano-silica surface grafted hydroxyl terminated polybutadiene rubber. The method includes: 1) synthesis of isocyanate terminated nano-silica: dispersing cleaned and activated nano-silica into an acetone solution, conducting ultrasonic dispersion for dozens of minutes, slowly adding a catalyst containing isophorone diisocyanate solution dropwise according to the mass ratio of nano-silica to isophorone diisocyanate of 1:1-3, carrying out reaction at 50-80DEG C for 3-6h, performing centrifugal collection, then using acetone to conduct ultrasonic dispersing, washing and centrifugation three to five times, thus obtaining nano-silica with surface containing an isocyanic acid group; and 2) synthesis of hydroxyl terminated polybutadiene rubber surface grafted modified nano-silica. The modified nano-silica has good dispersibility in butyl acetate solution, and the surface polymer grafting content is high.

The invention discloses a preparation method of a PET non-woven fabric with a photocatalytic degradation function. The preparation method sequentially comprises a first step, a second step, a third step and a fourth step, wherein the first step is a sample preparation step and comprises non-sequential first substep and a second substep, the first substep is preparation of cationic nano-wood cellulose, and the second substep is pretreatment of the PET non-woven fabric; the second step is an alkali etching step; the third step is a nano-wood cellulose grafting step; and the fourth step is a titanium dioxide grafting step. By comprehensively utilizing technical measures of alkali etching, acrylic acid bonding, cationic nano-wood cellulose modification and the like, the PET non-woven fabric which is originally difficult to be grafted can be effectively grafted with titanium dioxide, so that the PET non-woven fabric with the photocatalytic degradation function can be prepared from a large number of waste PET non-woven fabrics of factories such as an aluminum factory and can be applied to sewage treatment so as to realize reutilization.

The invention discloses a method for preparing a modified carbon nanotube-chitosan composite material. The method comprises the following steps: (1) modifying multi-walled carbon nanotubes with dopamine, so as to obtain dopamine modified carbon nanotubes; (2) subjecting a chitosan solution and a glutaraldehyde solution to a stirred and mixed reaction, and carrying out dialysis in distilled water, so as to obtain a chitosan-glutaraldehyde solution; preparing a 2mmol/L modified carbon nanotube solution from the modified carbon nanotube material obtained in the step (1), adding the modified carbon nanotube solution into the chitosan-glutaraldehyde solution, carrying out a reaction, then, adding a sodium borohydride solution, carrying out dialysis in distilled water, and then, carrying out standing, suction filtration, washing and drying. According to the method, the operation is simple, and the prepared modified carbon nanotube-chitosan composite material is high in chitosan graft amount, which is 71.78%, and presents excellent bacteriostatic performance to Escherichia coli, Staphylococcus aureus and Vibrio anguillarum, thereby having broad-spectrum bacteriostatic performance.

The invention relates to the field of medical devices, in particular to a preparation method of a surface-heparinized anticoagulation medical device based on ionic bond-covalent bond synergistic action. The method comprises the following steps: firstly, fixing heparin on the surface of a medical device by utilizing a hydrophilic polymer modified by low-molecular-weight hyperbranched polyethyleneimine as a side chain in an ionic bond combination manner; and furthermore, grafting a stable heparin coating through covalent bonds, so as to obtain the anticoagulant biomedical device with high anticoagulant activity and high anticoagulant stability. The device has a wide application value in the field of biomedical treatment. The method is simple in preparation process, high in controllability and low in material price, does not involve toxic reagents in the experiment process, has universality for various medical device structures, and is suitable for industrial production.

The invention discloses a preparation method of a high-quality breathable hot melt adhesive film. The preparation method comprises steps as follows: BPO (benzoyl peroxide) and DCP (dicumyl peroxide) in a mass ratio being 3:(1-1.5) are dissolved by ethyl acetate with the concentration of 30%, and an initiator solution is prepared; an EAA (ethylene acrylic acid copolymer) and MAH (maleic anhydride) in a mass ratio being 100:(1.5-2) are uniformly stirred in a blender mixer, the initiator solution is added to the blender mixer and is uniformly stirred, and then a modified hot melt adhesive raw material is prepared through melt grafting granulation by means of a double-screw granulator with seven temperature regions; an antioxidant, a hyperdispersant and an anti-blocking agent are added to the modified hot melt adhesive raw material, and a mixture is placed in a kneading machine for mixing; the mixture is subjected to extrusion by a single-screw extruder and is processed by an embossing and piercing roller, a casting machine and an expander, and a product is prepared. The modified hot melt adhesive adopts the EAA with low AA content, the EAA-graft-MAH grafting ratio is enabled to be higher and the MAH residue quantity is enabled to be lower through initiator compounding, preparation of the fisheye-free hot melt adhesive film with high polarity and excellent heat resistance is facilitated; the heat resistance and the adhesion performance are balanced, and the preparation method has wider application prospect.

The invention discloses a preparation method of a high-hexene grafted high-density polyethylene geomembrane blow molding material. The method comprises the following steps: (1) when a diluting agent is always under a circulation state, placing monomer ethylene and 1-hexene in a reaction vessel; adding an antistatic agent and an catalyst subjected to an activation treatment; adjusting the reaction temperature in the reaction vessel to 92-98 DEG C until the melt flow rate of a reaction product is 10.0-13.0g/10min and the density of the reaction product is 0.937-0.939kg/m<3>, thereby obtaining ethylene-hexene polyethylene copolymer base resin with weight average molecular weight of 200,000 to 300,000, 1-hexene content of not less than 1.20% and crystallinity of 46.5-49.5%; (2) uniformly mixing 99.5-99.8 parts of the ethylene-hexene polyethylene copolymer base resin and 0.20-0.50 part of an antioxidant; and adding the mixture to a mixer for extrusion granulation, so as to obtain the geomembrane blow molding material. According to the method, a high-activity novel chromium catalyst is adopted, the equipment limitation of a loop slurry process is overcome, and high-hexene grafted high-density polyethylene is produced. With the method, reaction scale is effectively ameliorated, a reactor wall attachment phenomenon is reduced, production is smooth, and the productivity of the special material is high.

The invention provides a preparation method of biocompatible silicone rubber. The method comprises the following steps: (1) fully stirring polydimethylsiloxane, adding a mixed crosslinking agent of a deoximation type crosslinking agent and a dealcoholization type crosslinking agent, continuously vacuumizing and stirring, adding a catalyst and vulcanizing at room temperature; (2) treating room temperature vulcanized silicone rubber by virtue of plasmas and generating hydroxyl active sites on the surface of the silicone rubber; adding silicone rubber and organic amine treated by plasma into a nonpolar solvent, stirring under an icy salt bath, dropwise adding a mixed liquid containing a brominating agent and a nonpolar solvent, removing the icy salt bath, raising to room temperature, and continuously stirring in a dark place to obtain silicone rubber with a bromine group on the surface; and (3) putting the silicone rubber with the bromine group on the surface, an acrylamide monomer and a CuCl/bpy catalyst in a reaction container, injecting a degassed solvent into the reaction container by virtue of an injector, and putting the reaction container in a constant temperature oil bath to react; and washing and drying to obtain hydrophilic silicone rubber grafted with polyacrylamide on the surface.

The invention discloses solid amine interpenetrating network porous amino resin and its preparation method and use. The preparation method comprises uniquely introducing polyacrylic acid into porous amino resin so that interpenetrating network porous amino resin is obtained and carrying out further amination treatment to obtain the solid amine interpenetrating network porous amino resin for physical and chemical combined adsorption of CO2 so that an adsorption amount is substantially improved. In preparation of the interpenetrating network porous amino resin, the preparation method is free of a pore forming agent, a catalyst and an initiator and realizes interpenetrating network porous amino resin preparation through direct solvent-based thermopolymerization at a low temperature. The product has strong stability, can be simply and easily prepared, can be massively produced, does not produce odor and toxic gas, can be post-treated simply and can satisfy green production requirements. Through use of acrylic acid, the product greatly improves swelling properties than those of the porous amino resin, can be fast swelled directly through water, can improve an amination reagent grafting amount and can realize physical and chemical combined high efficiency adsorption of CO2.

The invention discloses a cellulose aerogel modified by a polyionic liquid, a preparation method and application thereof. The cellulose aerogel is obtained by reacting cellulose aerogel CA-CTA modified by a chain transfer agent with an ionic liquid monomer and an initiator in DMSO at 50-80 DEG C in an inert gas atmosphere. According to the cellulose aerogel CA, hydroxyl on the surface of a cellulose aerogel is activated through carbonyl diimidazole CDI, hydrogenation esterification reaction is carried out on the CA to obtain chain transfer agent CTA modified CA, and then in-situ reversible addition fragmentation RAFT polymerization is carried out on the CTA modified CA surface to obtain the PIL functionalized CA material with high PIL grafting amount. The method has the advantages that thereaction conditions are mild, the grafting rate is high, and the obtained cellulose aerogel has an adsorption effect on anionic dyes, aromatic ring functional groups or anionic antibiotics.

The invention discloses a preparation method for an acrylate-modified epoxy resin cathode electrophoresis emulsion. The method adopts a monoprotic organic acid containing a double bond and a biproticorganic acid containing a double bond or/and an acid anhydride to react with epoxy resin, double bonds are introduced into a main chain of the epoxy resin, acrylic resin is grafted into the epoxy resin by utilizing copolymerization of the double bonds and an acrylate monomer, more acrylic resin can be introduced onto the main chain of the epoxy resin, adjustment and control of an introduction amount of the acrylate monomer are achieved through control of the content of the double bonds, and a molecular weight of the main epoxy resin is adjusted through a ratio of carboxyl to epoxy groups; themain body of the prepared product is epoxy resin, so that good anticorrosive performance of a paint film is guaranteed; and when the epoxy resin is aminated, two different organic amines are added step by step for a reaction, so that the reaction process is milder. According to the method disclosed by the invention, the acrylate-modified epoxy resin emulsion prepared by the method has good performance of a paint film and good ultraviolet and salt spray resistance, and can be used for workpieces under conditions of exposure under the sun.

The invention discloses a silk floss finishing method. The silk floss finishing method comprises the following steps of: A, preparing an amino-containing antibacterial agent finishing liquid, whereinthe amino-containing antibacterial agent comprises polylysine, chitosan with deacetylation exceeding 85% and chitosan quaternary ammonium salt with deacetylation exceeding 85% and substitution degreeof 60-90%, and dipping silk floss into the finishing liquid; B, adding laccase into the finishing liquid in the step A, and continuously dipping the silk floss subjected to dipping treatment in the step A; C, cleaning the silk floss treated in the step B in water; and D, drying the silk floss treated in the step C. The silk floss finishing method disclosed by the invention has the advantages thatby virtue of the laccase, the amino-containing antibacterial agent is grafted on the surface of silk floss fiber by catalysis, so that the silk floss product is endowed with antibacterial effect; andthe silk floss finishing method has the characteristics of safe treatment process and lower production energy consumption, and ecological functional processing of the silk floss product is realized.

The invention relates to a preparation method of a macroporous ion exchange resin capable of highly selectively adsorbing rhenium metal ions. According to the invention, gradient pore-forming is carried out by adopting a multi-element pore-forming agent, so that the pore channel structure is improved, the ion exchange resistance is reduced, and the ion exchange rate is increased. Glutaraldehyde isused as an amino modified cross-linking agent, so that the amino grafting amount is increased, the active center is increased, rapid diffusion and ion exchange of rhenium are facilitated, and the exchange capacity is further improved. Fe and Ce are adopted to carry out inorganic modification on the ion exchange resin together, so that the rhenium adsorption capacity is enhanced, and the selectivity is improved. When other ions are contained, the macroporous ion exchange resin prepared by the method has high rhenium selectivity, and the result shows that the macroporous ion exchange resin hashigh rhenium selectivity.