62results about How to "Uniform grafting" patented technology

The invention relates to a preparation method for a chitosan natural polymer modified crude oil desalting demulsifier. The method comprises the following steps: 1) modifying polyethylene glycol monomethyl ether by halogenating; 2) preparing glycidyl dimethyl alkyl ammonium chloride; 3) preparing quaternized carboxy alkyl chitosan; 4) causing the modified polyethylene glycol monomethyl ether to react with the quaternized carboxy alkyl chitosan, thereby obtaining a target product, polyethylene glycol monomethyl ether grafted quaternized carboxy alkyl chitosan. According to the invention, the chitosan natural high-molecular compound is taken as the raw material and has the advantages of wide resource, naturality, non-toxicity, sustainability, excellent biological compatibility of products, degradability, and the like. The demulsifier prepared according to the invention has excellent demulsification dewatering effect; the molecule of the demulsifier contains a large amount of carboxy alkyl groups and quaternary ammonium salt groups and the electronegative ions, including metal cation, naphthene acid radicals, and surfaces are electronegative grains and have strong combining capacity, so that the demulsifier has the capacities of demulsifying while removing oil-soluble salt.

The invention relates to a preparation method of a polyether-grafted chitosan derivative crude oil desalting demulsifier. The preparation method comprises the following specific steps: firstly, performing formylation modification on polyethylene glycol monoethylether; secondly, preparing glycidyl dimethyl alkyl ammonium chloride; thirdly, preparing quaternarization carboxyalkyl chitosan; fourthly, enabling formylation modified polyethylene glycol monoethylether to react with carboxy alkyl chitosan to obtain the polyether-grafted chitosan derivative crude oil desalting demulsifier. The polyether-grafted chitosan derivative crude oil desalting demulsifier disclosed by the invention is prepared by taking chitosannatural polymeric compounds as raw materials, and has the advantages of wide sources, naturalness, no toxicity, sustainability, good biocompatibility of a product, degradability and the like. The prepared demulsifier is good in demulsifying and dehydrating effect; meanwhile, a demulsifying molecule contains a large amount of carboxyalkyl groups and quaternary ammonium salt groups which have strong combining capacity to metal cation, ions with negative electricity such as naphthenic acid radicals as well as particles of which the surfaces are electronegative, so the polyether-grafted chitosan derivative crude oil desalting demulsifier has capacity of removing oil-soluble salts while demulsifying.

The invention relates to a synthesis method of a crude oil desalting demulsifying agent. The method specifically includes the steps of firstly, conducting p-nitrophenyl ester modification on methoxypolyethylene glycol; secondly, preparing glycidyl dimethyl alkyl ammonium chloride; thirdly, preparing quaternized carboxy alkyl chitosan; fourthly, making the modified methoxypolyethylene glycol react with quaternized carboxy alkyl chitosan to obtain a product, namely polyethylene glycol questin grafted quaternized carboxy alkyl chitosan. A chitosan type natural high-molecular compound serves as the raw material and has the advantages of being wide in resource, natural, free of toxin, sustainable, good in product biocompatibility, degradable and the like; The prepared demulsifying agent is good in demulsifying dewatering effect; meanwhile, due to the fact that lots of carboxy alkyl groups and quaternary ammonium salt groups are contained in demulsifying agent molecules and have strong binding capacity with metal cations, naphthenic acid radicals and other ions with negative charges and particles with surface electronegativity, the oil-soluble salt removing capacity is achieved during demulsifying.

The invention relates to a preparation method of a chitosan type crude oil desalting demulsifier. The preparation method includes the steps of firstly, performing epoxidation modification on methoxy polyethylene glycol; secondly, preparing glycidyl dimethyl alkyl ammonium chloride; thirdly, preparing quaternization carboxy alkyl chitosan; fourthly, allowing the modified methoxy polyethylene glycol to react with the quaternization carboxyl alkyl chitosan to obtain methoxy polyethylene glycol grafted quaternization carboxy alkyl chitosan. The preparation method has the advantages that chitosan type natural high-molecular compounds are used as the raw materials, the method is wide is source, natural, nontoxic and sustainable, and the product of the method is good in biocompatibility, degradable, and the like; the prepared demulsifier is good in demulsifying and dewatering effect, the demulsifier has high combining capacity to electronegative ions such as metal cations and naphthene acid radicals and electronegative particles due to the fact that the molecules of the demulsifier contain a large amount of carboxyl alkyl groups and quaternary ammonium salt groups, and oil-soluble salt can also be removed during demulsifying.

The invention discloses a linen fiber modification method, in particular to a linen fiber graft aminization modification craft, belonging to the technical field of printing and dyeing, which is characterized in that the linen fiber is selectively oxidized with oxidant solution such as sodium periodate, and oxidation linen fiber is obtained; the surface aldehyde group of the oxidation linen fiber is reacted with the surface amino of amine-terminated overbranched compound and the quaternary ammonium salt, which are combined by covalent bond, and the graft aminization linen fiber is prepared; the abundant amino, imino group and quaternary ammonium branched chain are introduced on the surface of obtained fiber, which can increase significantly the dyeing performance of linen fiber, and simultaneously increase the pliability softness, hygroscopicity and antibacterial performance of linen fiber. The linen fiber modification method has the advantages of fast reaction rate, high graft efficiency, good fastness, convenient and easy operation, realization of non-salt dyeing for linen fiber after modification treatment, environment protection, simplified normal dyeing craft and wide potential application.

The invention relates to the field of fabrics dyeing and finishing processes, in particular to a process for dyeing fabrics by combining with plasma and ultrasonic and a special device thereof. The special device comprises low-temperature normal-pressure plasma equipment, grafting reaction equipment, ultrasonic dyeing equipment, a rinsing bath and two groups of control systems, wherein the low-temperature normal-pressure plasma equipment, the grafting reaction equipment, the rinsing bath and the ultrasonic dyeing equipment are sequentially connected, one group of control systems is connected with the low-temperature normal-pressure plasma equipment, and the other group of control systems is connected with the ultrasonic dyeing equipment. The invention organically combines the low-temperature normal-pressure plasma equipment and the ultrasonic dyeing equipment, solves the problem that the dye uptake and the dyeing quality can not improved in a process of dyeing fabrics in a high crystalline region or solves the problem of high energy consumption and high pollution in the dyeing process, and can effectively realize that the dye uptake and the dyeing quality can be improved while realizing environmental-friendly production with low energy consumption and low pollution.

The invention relates to the medical material field, in particular to a method for preparation of a coating against drug-resistant bacteria on a medical catheter surface. The method for preparation ofthe coating against drug-resistant bacteria on a medical catheter surface includes the steps of: pretreating the medical catheter surface; immobilizing an initiator on the pretreated medical cathetersurface; grafting a positively charged organic small molecule or a positively charged polymer as the monomer on the medical catheter surface, taking methacrylate polyethylene glycol as the cross-linking agent, adopting a surface initiated-supplement reduced atom transfer radical chemical grafting method to finally obtain a polycation layer antibacterial coating. The coating obtained by the methodprovided by the invention has the advantages of uniform grafting, excellent anti-infection performance, and an anti-infection rate to drug-resistant bacteria of 99% or more.

The invention belongs to the technical field of electromagnetic shielding, and particularly relates to a modified carbon fiber, and a preparation method and an application thereof. The preparation method of the modified carbon fiber comprises the following steps: a) dipping a dopamine modified carbon fiber into a solution containing a substance A to obtain a substance A-dopamine modified carbon fiber; b) mixing and reacting the substance A-dopamine modified carbon fiber and a dopamine modified filler in a liquid phase under an alkaline condition to obtain a filler modified carbon fiber; and c)carbonizing the filler modified carbon fiber to obtain the modified carbon fiber. The problems of poor dispersibility and easy agglomeration of a small-scale filler in a modified material are solved,and the filler in the provided modified carbon fiber is uniformly dispersed and has excellent electromagnetic shielding performance; and a resin composite material prepared from the modified carbon fiber has good electromagnetic shielding performance and mechanical strength.

The invention relates to a ceramic membrane and an improved ceramic membrane chemical grafting modification method. A chemical modification layer exists on the surface of the ceramic membrane, no chemical modification layer is contained in pore channels of the inner wall, and the ceramic membrane shows good flux during liquid filtration. Meanwhile, according to the modification method provided by the invention, firstly, the ceramic membrane is filled with water through a vacuum pump, and then the surface of the membrane is placed at the interface of the organic solvent containing the silane modification liquid and the deionized water, so that the modified ceramic membrane with ideal surface properties is prepared. Through an interface chemical grafting modification method, the surface property of the ceramic membrane is adjusted, and the separation performance or the anti-pollution effect of the ceramic membrane is improved. Meanwhile, the grafting of the modified substance is limited in the surface area of the membrane, and only the aperture and porosity of the surface of the membrane are influenced. Compared with a modified membrane obtained by a traditional chemical grafting modification method, the modified membrane obtained by the method has the same modification effect, and meanwhile, attenuation of permeation flux is obviously reduced.

The invention discloses a method for preparing an ion exchange fiber by ultraviolet grafting. The method comprises the steps of cleaning a polypropylene knitmesh, extracting the polypropylene knitmesh with acetone, taking the polypropylene knitmesh out for drying, soaking the extracted polypropylene knitmesh in an acetone or alcohol solution with 10-30wt% of benzophenone, taking the polypropylene knitmesh out after 10-30 min for natural airing in a dark place, putting the aired polypropylene knitmesh in a quartz tube with grafting reaction liquid, removing oxygen in a test tube by supplying nitrogen, carrying out reaction for 30-120 min under ultraviolet irradiation, and finally carrying out water washing, acetone extraction and drying to obtain the ion exchange fiber grafted with a carboxyl functional group on the surface. A preparation route and a method which are low in equipment investment, simple in technology, energy-saving and efficient and have no environmental pollution are established, and the ion exchange fiber with the characteristic of efficiently absorbing heavy metal ions is obtained.

The invention discloses a nano-chitosan-modified cotton fiber and a preparation method of the nano-chitosan-modified cotton fiber. The preparation method of the nano-chitosan-modified cotton fiber comprises the steps: the cotton fiber is sent into a sodium hydroxide solution to be stirred, washed and dried, and sent into a sodium periodate solution to be stirred away from light to obtain an activated cotton fiber; nano chitosan, a cellulose dispersing agent and acetic acid are evenly mixed, isopropyl triisostearoyltitanate is added to be stirred, under the stirring state, tetraethylortho silicate is added, stirring is continued, and vacuum defoamation is conducted to obtain a pretreated nano chitosan solution; and the activated cotton fiber is steeped in the pretreated nano chitosan solution to be subjected to pulsed microwave treatment, filtered, and aired at the room temperature to obtain the nano-chitosan-modified cotton fiber. The cotton fiber is modified through the nano chitosanand thus has a good heat-insulating foundation and excellent antibacterial and anti-ultraviolet properties, the method is environmentally friendly, and the nano-chitosan-modified cotton fiber can be applied to the fields of medical health and antibacterial fabrics.

The invention discloses a preparation method for grafting maleic anhydride onto a plasma activated carbon nano tube. The method comprises the following steps: preparing the plasma activated carbon nano tube, preparing maleic anhydride dimethylbenzene solution, carrying out ultrasonic treatment on the plasma activated carbon nano tube, and utilizing microwaves to initiate the purification of the plasma activated carbon nano tube on which the maleic anhydride is grafted. The invention utilizes the plasma activated microwave induced grafting technology to improve the compatibility of a carbon nano tube with the maleic anhydride, and obtains the modified carbon nano tube with the highest grafting ratio of 15%. The invention has the advantages of easy obtainment of raw materials, simple operation, simple and convenient apparatuses, short grafting reaction time of 20-60 min, easy control of product performance and structure.

The invention discloses xanthan gum- azo-vinyl pyrrolidone graft copolymer and a preparation method and application thereof. The preparation method includes the following steps: evenly mixing N-vinyl pyrrolidone and xanthan gum in solvent, conducting irradiation on the mixture through gama ray produced by radioactive substances to obtain the xanthan gum- azo-vinyl pyrrolidone graft copolymer. In the method, the irradiation dose is 4-16 kGy, preferably 8-10 kGy, and more preferably 10kGy; mass ratio of the N- vinyl pyrrolidone and the xanthan gum is 2-14:1, preferably 8-10:1, and more preferably 10:1; dosage ratio of the xanthan gum and the solvent is 4-14g:1L, preferably 8-12g:1L, more preferably 10g:1L. The graft copolymer obtained in the method has high adsorption capability to both phenol and tea polyphenol and has important application value.

The invention discloses a composition for preparing an SEBS/PP blended grafted modification material and a preparation method adopting the same. The composition is prepared from, by mass, 90-100 parts of SEBS, 2-8 parts of MAH and 10-15 parts of PP. The preparation method comprises the steps that 1, all the components in the composition are weighed by mass of parts; 2, the weighed SEBS is subjected to forced air drying under the temperature of 55-65 DEG C for 24 h; 3, the dried SEBS is added into a feeder of a two-screw extruder; 4, the weighed MAH and PP are added into molten SEBS in the two-screw extruder for extrusion, and the two-screw rotating speed of the two-screw extruder is 60-150 rads/min; 5, extrudate is subjected to air cooling and grain-sized dicing to prepare granules; 6, the granules are subjected to radiation treatment by means of cobalt-60 radiation source under the limited oxygen phenomenon, the radiation dosage is 1-50 KGray, and the radiation time is 10-30 min. The SEBS/PP blended grafted modification material prepared through the formula and the preparation method ensures the bonding strength in the SEBS bonding process and also keeps the SEBS transparency.

The invention relates to a preparation method of chitosan oligosaccharide grafted cellulose fiber. The preparation method comprises following steps: A, preparation of sodium methallyl sulfonate-chitosan, wherein chitosan oligosaccharide is added into hot water to prepare a chitosan oligosaccharide aqueous solution, the chitosan oligosaccharide aqueous solution is cooled to room temperature, sodiummethallyl sulfonate is added into the chitosan oligosaccharide aqueous solution, an obtained mixture is subjected to stirring and heating, and potassium persulfate is added so as to obtain the sodiummethallyl sulfonate-chitosan oligosaccharide solution; B, cellulose fiber pretreatment, wherein cellulose fiber and soft water are introduced into a pretreatment tank, heating, stirring, water discharging, dehydration, and drying are carried out so as to obtain pretreated cellulose fiber; and C, preparation of chitosan oligosaccharide grafted cellulose fiber, wherein the cellulose fiber obtainedin step B is introduced into a reaction vessel, the sodium methallyl sulfonate-chitosan oligosaccharide solution obtained in step A is added, water is added, and stirring, heating, and centrifugal dewatering are carried out so as to obtain the chitosan oligosaccharide grafted cellulose fiber.

The invention discloses a charged nanofiltration membrane preparing method. According to the method, a newly-prepared ultrafiltration membrane serves as a base membrane, base membrane polymer is photosensitive polymer with a main chain or a side chain provided with carbonyl or sulfonyl, the base membrane is soaked in a rigid airtight container containing a grafting monomer solution after being cleaned, vacuumizing is conducted on the rigid airtight container after the base membrane is soaked, and the intensity of pressure in the container is made to be negative pressure; the processed base membrane is taken out to be placed under an ultraviolet lamp to conduct stem grafting in an illumination mode, nitrogen is injected to protect the base membrane, then the base membrane is taken out to be cleaned with deionized water more than three times, and a charged nanofiltration membrane is obtained. According to the method, an interfacial polymerization mode is adopted, the positively-charged nanofiltration membrane is prepared on the base membrane, the prepared nanofiltration membrane is charged, high in stability, high in retention rate and capable of achieving industrial production on the basis of an existing composite film production line.