Laser-induced phase-separation polymerization of a porous acrylatepolymer is used for in-situ fabrication of dialysis membranes inside glass microchannels. A shaped 355 nm laser beam is used to produce a porous polymer membrane with a thickness of about 15 μm, which bonds to the glass microchannel and form a semi-permeable membrane. Differential permeation through a membrane formed with pentaerythritol triacrylate was observed and quantified by comparing the response of the membrane to fluorescein and fluorescently tagging 200 nm latex microspheres. Differential permeation was observed and quantified by comparing the response to rhodamine 560 and lactalbuminprotein in a membrane formed with SPE-methylene bisacrylamide. The porous membranes illustrate the capability for the present technique to integrate sample cleanup into chip-based analysis systems.
The invention relates to an inverse emulsionpolymer thickener for a fracturing fluid and a preparation method thereof. The thickener is polymerized by water, 2-acrylamidyl-2-methyl sodium proparesulfonic acid liquid with mass fraction of 50%, alkylacrylamide, acrylamide, a cationic monomer, N, N-methylene bisacrylamide, a tween-80 emulsifier, ethylenediamine tetraacetic acid disodium salt, 30% sodiumhydroxide, white oil, acrylic ester, a span-80 emulsifier, sulfite, a peroxysulphate initiator, a water-soluble azo initiator and OP-15. According to the invention, raw materials are industrial products, and purification is not needed before reaction; polymerization is initiated by initiators by adding a complexing agent, and the preparation process is simple; the thickener provided by the invention is fast in dispersing, easy to prepare, free from pollution and harm, small in use level and good in stability, in particular resists high temperature of 220 DEG C, and is suitable for fracturing a high-temperature stratum; and the thickener is higher in shear resistance, can meet the fracturing construction of high flow, has high sand carrying performance, and is free from residue and is not harmful to the reservoir.
The invention relates to a core-shell polymermicrosphere profile control and oil displacement agent for oil reservoir profile control and displacement and increase of water drive recovery factor and a preparation method of the core-shell polymermicrosphere profile control and oil displacement agent, which can solve the technical problems of difficulty in injection and poor temperature resistance and salt resistance. The invention adopts a technical scheme as follows: the profile control and oil displacement agent is made from the following raw materials in parts: 15 to 20 of a hydrophobic monomer (such as styrene or a styrene derivative or an acrylate ester), 2 to 10 of a hydrophilic monomer (such as acrylic acid or an acrylate salt or acrylamide), 60 to 85 of deionized water, divinylbenzene as core-phase cross-linking agent, N,N'-methylene-bis-acrylamide as shell-phase cross-linking agent, and a sulfate salt as initiator. The method comprises the following steps of: adding the shell-phase cross-linking agent and acrylic acid into a three-necked flask with water, adding the core-phase cross-linking agent and styrene after dissolving completely, introducing nitrogen gas (30 DEG Cto 75 DEG C), adding the initiator, and allowing reactions to take place for 6 to 8 hours under stirring, to obtain the polymermicrosphere profile control and oil displacement agent. The polymer microsphere profile control and oil displacement agent is suitable for middle / low-permeability oil reservoirs, can be applied to high-permeability oil reservoirs in combination with other profile controlagents, and can greatly increase the crude oilrecovery ratio.
The invention relates to a method for water plugging and profile controlling of underground polymerization of oil exploitation sludge, comprising the following steps of: adding 2-7% of crylic acid, 0-3% of acrylamide, 0.2-0.6% of cross linking agent and 0.01-0.05% of initiator into 15-25% of oil exploitation sludge, injecting the mixture together with the oil field water or tap water in the ground; and subsequently generating plugging substances of solid mesh structure wrapping sludge owning to the polymerization reaction under the action of oil pool temperature, thus playing an effect of sealing the underground seams, wherein the oil exploitation sludge is a tank bottom sludge generated during the oil exploitation process of the oil field or the sludge in the sludge pool; the sludge is athin oil sludge; the cross linking agent is a polyol, a glycerin, an N, N-methylene bisacrylamide or N, N-dimethybisacrylamide; and the initiator is the alkali metal salt or the ammonium salt of a persulphuric acid. The method changes the aboveground polymerization process of the oil exploitation sludge grain profile control agent into the underground polymerization process, saves corresponding procedures and the equipment and devices, and generates the water-plugging profile control agent with high intensity and long-term effect by adjusting the concentration of the monomer.
The invention discloses grapheneaerogel and a hybridcomposite material thereof as well as a preparation method and application of the of grapheneaerogel. The preparation method comprises the following steps: 1) mixing grapheneoxide, a reducing agent, acrylamide, N,N-methylene-bisacrylamide and potassiumpersulfate and reacting to obtain partially-reduced graphene / polyacrylamide hydrogel; 2) carrying out pre-freezing and reduction on the partially-reduced graphene / polyacrylamide hydrogel in sequence to obtain graphene / polyacrylamide hydrogel; 3) dialyzing and drying the graphene / polyacrylamide hydrogel in sequence to obtain the graphene aerogel. The graphene aerogel has the characteristics of uniform cellular structure and light weight, excellent resilience, relatively high mechanical strength and good solvent resistance; a preparation process is simple, rapid and low in cost; the graphene aerogel can also be used for preparing polymer / graphene composite aerogel, nanoparticle / graphene composite aerogel and polymer / graphene composite materials and the like, so that application of the graphene aerogel is expanded.
The embodiments herein disclose a nano-composite superabsorbent polymer (NC-SAP) composition encapsulating fertilizer / plantnutrient products and a method of producing NC-SAP based products. According to one embodiment, the method involves graft polymerizing a monomer, other than acrylonitrile, onto a carbohydrate in the presence of an initiator to form a graft carbohydratecopolymer, dispersing an inorganic nano powder, adding fertilizernutrient to the reaction mixture, cross-linking the carbohydrate graft copolymer by adding a cross-linking agent, such as methylene bis-acrylamide, adjusting the pH of the cross-linked nano-composite carbohydrate graft copolymer and isolating the nano-composite carbohydrate graft copolymer. The method also includes drying the nano-composite carbohydrate graft copolymer, to yield particles that are NC-SAP containing fertilizer. The isolation of particles of NC-SAP polymer product may occur by the methods, including, but not limited to, granularization, extrusion and pelletization.
The invention discloses a method for preparing high-strength polyvinyl alcohol-based dual-network hydrogel. The method comprises the following steps: taking polyvinyl alcohol as an initial raw material, and heating for dissolving, so as to obtain polyvinyl alcoholaqueous solution; adding metric acrylamide, acrylic acid, a cross-linking agent N'-N-methylene bisacrylamide and an initiator Irgacure2959 into the polyvinyl alcohol solution, and heating for dissolving, so as to obtain a uniform solution; freezing the solution in a low-temperature environment so as to obtain a physical cross-linked network structure of polyvinyl alcohol; performing photo-initiation under ultraviolet light so as to obtain chemically cross-linked polyacrylamide-acrylic acid chemical cross-linking structure, and constructing the high-strength polyvinyl alcohol-based dual-network hydrogel. The physical cross-linked and chemical cross-linked dual-network structures can be sequentially constructed by a one-step process. The preparation method provided by the invention is simple and feasible, the high-strength hydrogel of any shape can be constructed, and the prepared dual-network hydrogel is excellent in mechanical property.
The invention relates to a controllable cross linking gel water shutoff and lost circulation material used for oil-gas fields, which can block off a fractured, vuggy or malignant leaking formation and increase the strength and stability of gel. The technical proposal is as follows: acrylamide of certain amount is added into a breaker containing deionized water, after the acrylamide dissolved, N, N-methylene-bisacrylamide and initiating agent are added, the mixture stands still for 1h at room temperature after 0.5h of gelation, therefore, lump gel product is obtained and finally becomes gel particles after granulation, parching and sieving; the gel particles are then soaked in the solution of chromium trichloride, cross linker is fully absorbed in the gel particles, and the obtained material is dried for spare; the product is then added into the solution of polyvinyl alcohol and the packaged gel particles are obtained after packaging 1-3 times and drying; finally the packaged gel particles containing the cross linker are added into the solution of the water solublepolymer HPAM for slow cross linking reaction, thus obtaining quiescent strong gel. The material is characterized by simple manufacturing process, low cost, little filtration loss and good leak tightness and stability.
The invention discloses a modified petroleumcoke granule composite profile control water blocking agent and a multi-round bidirectional blocking control technology. The water blocking agent comprises agents A, B and C, the agent A comprises the ingredients: polyacrylamide solution with the concentration of 0.1-0.3% (by weight), sodiumsilicate, aluminum potassium sulfate, hydrochloric acid with the concentration of 30% ( by weight), and calciumchloride, the agent B comprises polyacrylamide solution with the concentration of 0.1-0.3% (by weight), modified petroleumcoke granules of 20-800mum and surfactant, and the agent C comprises the ingredients: polyacrylamide solution with the concentration of 0.3-0.7% (by weight), N-N' methylene bisacrylamide, organic chromium crosslinking agent, and thiocarbamide; and the multi-round bidirectional blocking control technology is of a multi-round bidirectional blocking control measure developed according to geologic features, state and oil producing conditions of different regions of oil fields; and the water blocking agent is matched with the blocking control technology, so that the problems that the conventional profile control water blocking agent is low in strength, and bad in anti-erosion property and shearing resistance property can be solved, further digging of remaining petroleum is conducted, the water content ratio of an oil well can be reduced, the effect of displacement in flooding can be improved, and the production demand of the oil field can be met.
The invention discloses a polyacrylamide microgel as well as a preparation method and application thereof. The particle size of the polyacrylamide microgel is 30-150 micrometers, acrylamide, sodiumacrylate, N,N'-bisacrylamide, 2-acrylamide-2-methylpropanesulfonic acid sodium, styrenesulfonate and the like serve as polymerized monomers, white oil and the like serve as disperse phases, and the polymerized monomers and the disperse phases are subjected to thermal initiationsuspension polymerization to obtain the polyacrylamide microgel. The polyacrylamide microgel synthetized by the method can be directly injected into an oil layer without being processed and has a good plugging effect.
Disclosed is a process for preparing YAG nano-powder, which belongs to the inorganic materials and the preparation field. The invention utilizes acrylamide as monomer, employs N, N'-methylene diacrylamide as polymernetwork agent, utilizes Al(NO3)3Y(NO3)3, Ce(NO3)3*6H2O as raw materials, employs citric acid as regulator, and uses a polymer network gel method and an active carbon adsorption process to prepare the nano-powder of Y3Al5O12(YAG):Ce3+. The method is characterized in that requirements to raw materials are simple and inorganic saline solution can be utilized as the raw materials, the component of the obtained micro powder is mixed evenly, most importantly, the polymer network formed in the gel process and the active carbon decomposed under nitridingatmosphere reduce the contact opportunity of precursor grains, thereby agglomeration is reduced, the nano-powder which is small in grain size and uniform in dispersion can be obtained, thereby largely reducing preparation temperature of materials, and calcination temperature is only 800 DEG C.
The invention relates to a farmland soil water-holding agent, in particular to a soil water-holding agent and a preparation method thereof. The soil water-holding agent is prepared by the following solutions according to the parts by weight: 100-150 of modified corn straw solution, 100-300 of sodium polyacrylate solution, 5-20 of ammoniumpersulfate solution and 1-12 of N, N '-methylenebisacrylamide solution. The preparation method comprises the following steps: the modified corn straw solution, the sodium polyacrylate solution and the N, N '-methylenebisacrylamide solution are mixed according to a certain proportion, evenly blended and added with the 5-20 parts of the ammoniumpersulfate solution after a period of time and then react for a period of time under the protection of nitrogenatmosphere at the temperature of 50-90 DEG C to obtain transparent colloid; and the colloid is dried, crushed and sieved to obtain yellow brown soil water-holding agent solid particles. The soil water-holding agent has good hydroscopicity and mechanical property, low price and better application prospect.
Owner:SHENYANG INST OF APPL ECOLOGY CHINESE ACAD OF SCI
The invention belongs to the technical field of high polymer materials and specifically discloses modified chitosan / nanocellulose composite aerogel and a preparation method and application thereof. The preparation method comprises the following steps: letting pretreated chitosan react with a hydrochloric acid solution, adding dithiobispropionate, and reacting to prepare modified chitosan; dissolving modified chitosan with an acetic acid solution, adding nanocellulose and fully reacting; adding potassium peroxodisulfate and uniformly mixing; adding acrylic acid and NaOH solution and fully dissolving; adding a N,N'-methylene bisacrylamide solution to prepare modified chitosan / nanocellulose composite aerogel, and freeze-drying to obtain the aerogel product. The prepared modified chitosan / nanocellulose composite aerogel has efficiency and enhanced adsorptive property, and has a remarkable effect of adsorbing heavy metal Cu<2+> with low concentration. Meanwhile, the preparation technology is simple and has strong operability.