7327results about How to "Improve thermal stability" patented technology

The invention provides an acetylacetone-based composite thermal stabilizer which is a mixture obtained by mixing zinc acetylacetonate, calcium acetylacetonate or magnesium acetylacetonate and hydrotalcite pro rata. The composite thermal stabilizer is suitable for chloride-containing high polymer, such as polyvinyl chloride, chlorinated polyethylene, chlorinated polyvinyl chloride, copolymer of vinyl chloride-ethylene or copolymer of vinyl chloride-vinyl acetate, has better thermal stability, prolongs the thermal aging time of the chloride-containing high polymer, and overcomes the shortcomings of poor long-term performance of single stabilizer of zinc acetylacetonate, poor transparency of stabilizer of calcium acetylacetonate, and poor initial colorability of stabilizer of hydrotalcite. The composite thermal stabilizer has low cost, good initial colorability, excellent long-term performance and good transparency, and is an efficient composite thermal stabilizer.

The invention relates to a ring structure betaine and double-tailed hydrophobic association polymer fracturing thickening agent and a preparation method thereof. The thickening agent is formed by copolymerization of four monomers, namely acrylamide, 2-allyl methylamino sodium ethanesulfonate, methyl diallyl sulfoethyl betaine and hydrophobic monomer double-tailed long-chain alkyl methyl allyl ammonium chloride. The preparation method comprises the following steps: firstly adding distilled water, then sequentially adding acrylamide, 2-allyl methylamino sodium ethanesulfonate, methyl diallyl sulfoethyl betaine and a hydrophobic monomer double-tailed long-chain alkyl methyl allyl ammonium chloride, adjusting the total concentration, introducing N2 to remove oxygen, adding an initiator, and reacting to prepare an AM / AMES / MDASBA / DCnMAAC quadripolymer, namely the polymer fracturing thickening agent. The thickening agent provided by the invention has good water solubility, and shows good salt resistance in mixed brine with the mineralization degree of greater than or equal to 30000 mg / L. The prepared linear solution and gel formed after crosslinking have high viscosity retention capacity at the temperature of 150 DEG C and the shearing rate of 170 s <-1 >, and the actual construction requirement for fracturing yield increase with the on-site mineralization degree larger than or equal to 30000 mg / L is met.

The invention belongs to the technical field of biodegradable materials, and particularly relates to an environment-friendly degradable modified composite material, a preparation method and application. The material comprises PBAT, PBS, PLA, an inorganic mineral filler, natural plant fibers, PBAT-PTMO, nano-silica, an auxiliary agent and a plasticizer. In the preparation process, PLA is prevented from being hydrolyzed in vacuum drying, calcium carbonate and nano silicon dioxide are preheated and activated, natural plant fibers are dispersed through steam explosion and ethanol treatment, and raw material pretreatment comprises high-speed mixing and agglomeration breaking and medium-speed secondary premixing so as to realize uniform distribution. The co-rotating twin-screw extruder accurately controls the temperature, the speed, the rotating speed and the length-diameter ratio, and ensures melting plasticizing, uniform mixing and stable extrusion molding. According to the invention, by adopting accurate proportioning of multiple raw materials and a modification treatment process, the properties of mechanics, degradation, processing and the like of the material are synergistically improved, and the material is widely applied to multiple fields such as packaging bags, disposable tableware and agricultural plastic mulching films.

The invention discloses an environment-friendly calcium-zinc composite heat stabilizer and a preparation method thereof, and relates to the technical field of heat stabilizers. The environment-friendly calcium-zinc composite heat stabilizer is prepared from the following raw materials in parts by mass: 10-20 parts of zinc stearate, 20-30 parts of calcium stearate, 10-15 parts of an auxiliary stabilizer, 5-8 parts of a plasticizer, 1-5 parts of an antioxidant and 2-5 parts of filler, wherein the auxiliary stabilizer is a mixture of beta-diketone, modified organic acid intercalated hydrotalcite and modified silicon dioxide; the modified organic acid intercalated hydrotalcite is obtained by splitting expanded vermiculite, adding zinc and lanthanum compounds, coprecipitating with organic acid, and adding a modifier; the modified silicon dioxide is obtained by adding a coupling agent into a solid substance obtained by splitting expanded vermiculite for modification and carrying out a series of chemical reactions with maleic anhydride and pentaerythritol. PVC plastic prepared by adding the calcium-zinc composite stabilizer into PVC paste resin and resin powder has good thermal stability.

The invention relates to the technical field of nano ceramic materials, and discloses a high-strength nano aluminum oxide ceramic product and a preparation process thereof.The preparation process comprises the following preparation steps that aluminum oxide powder, a composite binder, composite gel, a plasticizer and a solvent are mixed and subjected to ball milling, and composite slurry is obtained; placing the composite slurry in a mold, and performing mold pressing and drying to obtain a green body; and putting the green body into a high-temperature sintering furnace, carrying out high-temperature sintering, and cooling to room temperature to obtain the nano aluminum oxide ceramic product. Nano zirconium oxide and nano magnesium oxide are formed on the surfaces of the pretreated silicon carbide whiskers, and can form a solid solution with nano aluminum oxide in the sintering process to serve as a bridge of the silicon carbide whiskers and nano aluminum oxide particles, so that the binding force of the silicon carbide whiskers in a nano aluminum oxide ceramic matrix is remarkably enhanced; phosphoric acid and aluminum ammonium sulfate are firmly combined on the surfaces of nanometer aluminum oxide particles through carboxymethyl cellulose, and the situation that phosphoric acid and aluminum ammonium sulfate are not firmly combined with the nanometer aluminum oxide particles is avoided.

The invention provides a positive plate, a preparation method thereof and a battery. The positive plate comprises a positive current collector, and a first positive active coating and a second positive active coating which are sequentially arranged on at least one side of the positive current collector, the first positive electrode active coating is close to one side of the positive electrode current collector, and the first positive electrode active coating comprises a first manganese iron lithium phosphate active material and a nickel-cobalt-manganese ternary active material; in the first positive electrode active coating, the mass ratio of the first lithium manganese iron phosphate active material to the nickel-cobalt-manganese ternary active material is (80-90): (8-15); the second positive electrode active coating is far away from one side of the positive electrode current collector, and the second positive electrode active coating comprises a second lithium manganese iron phosphate active material; the surface density rho1 of the first positive electrode active coating and the surface density rho2 of the second positive electrode active coating meet the following conditions: rho1 is greater than or equal to 240 g / m < 2 >, and rho2 is greater than or equal to 240 g / m < 2 >; and rho1-rho2 is less than or equal to 5g / m < 2 >. The positive plate has relatively high electron conduction and ion conduction performance, meanwhile, the polarization of the positive plate is effectively reduced, and the cycle performance and the thermal stability of the battery are greatly improved.

The invention belongs to the technical field of polymer plastic materials, and particularly relates to a high-temperature-resistant anti-corrosion polytetrafluoroethylene material and a preparation method thereof. The polytetrafluoroethylene is prepared from the following raw materials in parts by weight: 50 to 60 parts of polytetrafluoroethylene, 5 to 10 parts of fluorinated modified graphene oxide, 3 to 5 parts of aluminum powder, 5 to 8 parts of modified silicon carbide fiber, 3 to 5 parts of silane modified nano silicon dioxide, 2 to 3 parts of polyphenylene sulfide, 2 to 3 parts of polyimide, 0.5 to 0.8 part of dispersing agent and 0.5 to 1 part of antioxidant. The heat conduction performance and the interface bonding force are improved through the fluorinated modified graphene oxide, the impact resistance and the wear resistance are enhanced through the silicon carbide fibers, and the corrosion resistance and the wear resistance are improved through the aluminum powder; silane modified silicon dioxide enhances the mechanical property of the composite material by improving the dispersity of the filler, and PPS and PI interact with the surface of the filler through polar groups in molecular chains, so that the interface strength is improved, and the toughness and the thermal stability are improved.

The invention discloses a copper alloy pipe and a preparation method and application thereof, and the copper alloy pipe comprises the following components in percentage by mass: 0.01%-0.80% of Sn, 0.005%-0.05% of P, 0.01%-0.10% of Zr, 0.001%-0.01% of B, 0.001%-0.01% of Mn and the balance of Cu and inevitable impurities. Wherein the copper alloy pipe contains MnZr and BMn compound particles, the number of the MnZr compound particles on the cross section of the copper alloy pipe is 0.005-0.15 / mu m < 2 >, and the number of the BMn compound particles on the cross section of the copper alloy pipe is 0.005-0.2 / mu m < 2 >. By adding Zr, B and Mn and controlling the content of Zr, B and Mn, the preparation process and the like, the number and uniformity of MnZr and MnB compounds are regulated and controlled, and the tensile strength, ductility, corrosion resistance, bending, flaring, welding, pressure resistance and other machining performance of the copper alloy pipe are improved; and the prepared copper alloy pipe fully meets the application requirements of heat conduction pipes of air conditioner heat exchangers, air conditioner indoor and outdoor unit connecting piping and the like.

The invention provides a thermal-stability glucose oxidase mutant, polynucleotide for encoding the glucose oxidase mutant, a recombinant expression vector containing the polynucleotide, a host cell for expressing the glucose oxidase mutant, and applications of the thermal-stability glucose oxidase mutant, the polynucleotide, the recombinant expression vector and the host cell in the fields of food, chemical industry, medicine, agriculture or feed.

The invention belongs to the technical field of composite fiber materials, and relates to a functional thermal management fabric, in particular to a phase change microcapsule doped flexible cooling fiber fabric and a preparation method thereof. The fabric has a controllable double-layer structure and is formed by assembling nanofibers and micro-nanofibers doped with a large number of phase change microcapsules. Wherein the micro-nano fiber layer has relatively high sunlight reflectivity and atmospheric window wave band emissivity, and shows an excellent radiation cooling effect; the microcapsule content of the nanofiber layer doped with a large amount of phase change microcapsules is not less than 10 wt%, and the nanofiber layer has no rupture phenomenon, has high heat storage capacity, not only makes up for the deficiency of radiation cooling capacity, but also effectively slows down temperature fluctuation. The radiation cooling technology and the phase change latent heat technology are combined, so that the long-time temperature control performance of the fabric is realized, and the thermal shock resistance is enhanced. In addition, the fabric also has excellent mechanical property, flexibility, washability, air permeability, moisture penetrability and sunscreen property.

The invention relates to the technical field of electronic ceramic materials, and particularly discloses a high-purity aluminum oxide ceramic substrate and a preparation process thereof. The high-purity aluminum oxide ceramic substrate is prepared from the following raw materials in parts by weight: 0.20 to 0.25 part of magnesium oxide, 0.35 to 0.55 part of zirconium oxide, 1.2 to 1.5 parts of dispersing agent, 60 to 65 parts of ethanol, 99.7 to 99.8 parts of aluminum oxide, 12 to 15 parts of adhesive, 6 to 9 parts of plasticizer and 50 to 55 parts of n-butyl alcohol, the adhesive is a mixture of polyvinyl butyral, water glass and modified paraffin. The prepared high-purity aluminum oxide ceramic substrate has excellent chemical stability and mechanical strength, and the obtained aluminum oxide ceramic substrate has better density, mechanical property and thermal stability by mixing various raw material components, and is not easy to break when subjected to bending load.

The invention provides a sodium-ion battery positive electrode material and a preparation method thereof, a sodium-ion battery and electric equipment, and relates to the field of sodium-ion batteries. The positive electrode material of the sodium ion battery provided by the invention comprises an inner core and a shell, wherein the shell covers the inner core; the chemical formula of the inner core is NaaNixFeyMnzM1-x-y-zO2, wherein a is more than or equal to 0.9 and less than or equal to 1.05, x is more than 0 and less than 1.0, y is more than 0 and less than 1.0, z is more than 0 and less than 1.0, and 1-x-y-z is more than 0 and less than 1; the chemical formula of the shell is NaLarCa1-rO2, wherein r is more than 0 and less than 1; in the inner core, the element M comprises one or more of Al, Mg, Ti, Zr, Y, La, Ca, Zn, Cu, W, Li and B. The sodium-ion battery positive electrode material provided by the invention can reduce residual alkali on the surfaces of particles, can inhibit side reaction with an electrolyte, and improves the performance stability of the positive electrode material.

The invention provides antibacterial ceramic and a preparation method thereof. The antibacterial ceramic comprises a blank body and a glaze layer, the blank body is prepared from the following raw materials: kaolin, diatomite, montmorillonite, soapstone, bamboo charcoal powder, a first antibacterial agent, a fluxing agent, a pore forming agent, an adhesive and a reinforcing agent; the glaze layer comprises the following raw materials: kaolin, diatomite, dolomite, tourmaline, sodium oxide, a second antibacterial agent, a binder, a stabilizer and a dispersant. The method comprises the following steps: firing a molded green body by adopting stepped segmented heating, and carrying out glaze firing by adopting stepped segmented heating after glazing, thereby obtaining the antibacterial ceramic. According to the antibacterial ceramic disclosed by the invention, the antibacterial agent is added into the green body and the glaze layer, so that the influence on the antibacterial property of the green body in the firing process of the green body is avoided, the antibacterial durability is further improved, the antibacterial effect is enhanced, and the antibacterial rate on pathogenic bacteria such as escherichia coli and staphylococcus aureus reaches 99.99%.

The invention belongs to the technical field of engineering plastics, and particularly relates to a high-flame-retardant composite material and a preparation method thereof. The composite material comprises the following components: long-carbon-chain semi-aromatic nylon, a fiber reinforced filler, a flexibilizer, alkyl aluminum phosphinate, nano montmorillonite, a zinc ion ionomer, a coupling agent, a lubricant and an antioxidant. Alkyl aluminum phosphinate is used as a main flame retardant, and nano-montmorillonite and a zinc ion ionomer are used as auxiliary flame retardants. The nano-scale montmorillonite has certain adsorption performance, and can prevent the alkyl aluminum phosphinate flame retardant from being separated out in the processing process. The zinc ion ionomer is easier to disperse in a long-carbon-chain semi-aromatic nylon resin matrix relative to alkyl aluminum phosphinate and nano-montmorillonite, and ion groups contained in the zinc ion ionomer can generate an ionic crosslinking effect with ions in alkyl aluminum phosphinate and nano-montmorillonite, so that the mechanical property and the thermal stability of the composite material are improved; and moreover, the melt viscosity is improved, and the molten drop phenomenon during combustion is prevented.

The invention discloses a fusion enzyme capable of efficiently degrading PET (polyethylene terephthalate) plastic and application of the fusion enzyme. The invention provides a recombinant fusion enzyme. The recombinant fusion enzyme comprises a mutant KL-MHETase of thermophilic carboxylesterase Est30 and a PET (Polyethylene Terephthalate) degrading enzyme FAST-PETase, the amino acid sequence of the mutant KL-MHETase of the thermophilic carboxylesterase Est30 is as shown in SEQ ID NO. 3; the amino acid sequence of the FAST-PETase is as shown in the 284th to 546th amino acids of SEQ ID NO.1 (Sequence Identifier Number 1). The fusion enzyme is used as a biocatalyst, the activity of catalyzing hydrolysis of MHET at 50 DEG C is 52.6 times that of FAST-PETase, and the fusion enzyme has high enzyme activity and thermal stability. PET degradation is catalyzed at the temperature of 50 DEG C, the conversion rate of PET is 90% after 48 hours of reaction, and meanwhile, the TPA content in the product is close to 100%.

The invention discloses one-step solvent-free methyl phenyl-terminated vinyl polysiloxane and silica gel, and the methyl phenyl-terminated vinyl polysiloxane is prepared by the following steps: adding octamethylcyclotetrasiloxane, octaphenylcyclotetrasiloxane and dimethyl-terminated vinyl silicone oil into a reaction container, and uniformly stirring; vacuumizing the reaction container, and introducing nitrogen to form an oxygen-free environment; heating the reaction container to 180-200 DEG C step by step, and adding a catalyst at 50-80 DEG C; the step-by-step heating comprises a first-stage pre-polymerization reaction at the temperature of 90 DEG C or below and a second-stage polymerization reaction at the temperature of 90 DEG C or above, and methyl phenyl vinyl-terminated polysiloxane is prepared. The high-temperature-resistant and high-pressure-resistant methyl phenyl silica gel is obtained by mixing methyl phenyl vinyl-terminated polysiloxane with an inhibitor, a cross-linking agent and a cross-linking catalyst, degassing, heating, cross-linking and curing, the performance requirements of high-power semiconductor devices on high-pressure resistance, high-temperature resistance and the like of packaging materials can be met, the product quality is stable, and the production efficiency is high.

The invention belongs to the field of molecular biology and immunology, and particularly relates to an anti-CD3 nano antibody capable of activating the activity of T cells as well as a preparation method and application of the anti-CD3 nano antibody. The invention provides a preparation method of the anti-CD3 nano antibody. The preparation method comprises the following steps: constructing a CD3 plasmid and an overexpression cell line, and immunizing alpaca to obtain peripheral blood mononuclear cells (PBMC) of the alpaca; extracting RNA (Ribonucleic Acid) and carrying out reverse transcription to obtain cDNA; carrying out PCR amplification on the antibody gene segment and cloning the antibody gene segment to a phage display vector; and electrically transforming the vector into SS320 competent cells to obtain the nano antibody library. After two rounds of panning, detecting and screening an antibody clone capable of being combined with the CD3 protein through ELISA (Enzyme-Linked Immunosorbent Assay); an antibody sequence is selected through sequencing, and an antibody protein is expressed by using a mammalian cell high-throughput expression system; and then detecting and screening the antibody which is only specifically combined with the CD3. The method disclosed by the invention is simple, convenient and rapid to operate, and can be used for preparing active antibodies for treating potential tumors and proliferative diseases.

The invention relates to the technical field of organic photoelectric materials, in particular to a triazine compound, an OLED with the compound and an organic light-emitting device with the compound. According to the triazine compound disclosed by the invention, a triazine structure is taken as a core, and aryl and alkyl are combined with a fluorenyl group to form side chain matching, so that the compound has excellent luminous efficiency and relatively good thermal stability; meanwhile, when the triazine compound provided by the invention acts on a device, the organic light-emitting device can effectively have lower driving voltage and maintain the stability of the voltage, the light-emitting efficiency is improved, the service life is obviously prolonged, and the triazine compound has a very good application prospect.

The invention relates to a halogen-free intrinsic flame-retardant waterborne polyurethane material and a preparation method thereof, and belongs to the field of functional polymer materials and fine chemical engineering. The halogen-based flame-retardant waterborne polyurethane disclosed by the invention is prepared from diisocyanate, long-carbon-chain polyether polyol, a catalyst, a chain extender, deionized water and a salt-forming agent through reaction; the hydrophilic chain extender is prepared from pentaerythritol, phosphorus oxychloride and p-hydroxyphenylpropionitrile through a reaction, and is a flame-retardant chain extender of a diamine structure containing phosphorus and nitrogen flame-retardant elements. The waterborne polyurethane material prepared by the method has a certain flame-retardant effect, and is simple in preparation process, relatively low in cost, very good in practicability and economical efficiency and good in market prospect.

The invention provides sulfonated cellulose. The sulfonated cellulose is obtained by etherifying alkalized cellulose with water-soluble halogenated sulfonate. Compared with the prior art, the sulfonated cellulose provided by the invention contains sulfonic acid groups, hydroxyl groups and other groups, so that when the sulfonated cellulose is used in the drilling fluid, the filter loss of the drilling fluid can be effectively controlled, and meanwhile, the salt pollution resistance, especially the calcium ion pollution resistance, of the drilling fluid can be improved; in addition, sulfonic groups in the product are also beneficial to improving the thermal stability of the drilling fluid, and the application range is expanded. In a word, compared with carboxymethyl cellulose for drilling fluid, sulfonated cellulose provided by the invention has obvious temperature resistance and high-valence metal ion resistance.

The invention discloses a method for preparing asphalt-based porous carbon based on an MgO template, and belongs to the technical field of porous carbon, nano MgO and deionized water are mixed and placed in a synthesis kettle, hydrothermal synthesis is performed at 180 DEG C for 2 h, suction filtration and drying are performed, a dried filter cake is crushed and calcined, and porous flaky MgO is obtained; adding the asphalt solution into the MgO suspension, stirring, drying to obtain brown powder, transferring the brown powder into a corundum crucible, putting the corundum crucible into a tubular furnace, calcining to obtain a carbonized C / MgO composite material, and washing the carbonized C / MgO composite material with a diluted hydrochloric acid solution and deionized water to obtain a carbon material sample recorded as AC-75. Pouring the porous carbon material PCs and KOH into a mortar, fully grinding, mixing and calcining to obtain an activated product, pickling and washing the product to be neutral, and drying to obtain the porous carbon material PCs. The raw materials selected by the method are asphalt and flake magnesium oxide which are stable in performance, low in price, large in amount and easy to obtain, a magnesium source can be recycled, environmental protection is achieved, and resources are saved.

The invention belongs to the technical field of polyurethane pouring sealants, and particularly relates to a two-component hydrophobic heat-resistant polyurethane pouring sealant and a preparation method thereof. The pouring sealant is prepared by reacting a component A and a component B, the component A is prepared from the following raw materials in parts by weight: 17 to 33 parts of modified polyether polyol I; 15 to 27 parts of modified polyether polyol II; 18 to 30 parts of diisocyanate; 20 to 34 parts of a plasticizer; the component B is prepared from the following raw materials in parts by weight: 47 to 64 parts of polyether polyol III; 36 to 53 parts of filler; and 0.15 to 0.35 part of a catalyst. Introducing a silicon-oxygen-silicon chain segment into a polyether polyol structure through acrylic acid bridging to prepare siloxane modified polyether polyol; more side ethyl, phenyl and neopentyl structures are introduced into the polyether polyol, so that the intrinsic hydrophobicity and temperature resistance of the raw materials are further improved, and the polyurethane pouring sealant shows relatively high hydrophobicity and heat resistance.

The invention provides a redox imidazole covalent organic framework material as well as a preparation method and application thereof, belongs to the technical field of material preparation and photocatalytic preparation of hydrogen peroxide, and aims to solve the technical problem of low activity of a current covalent organic framework in preparation of hydrogen peroxide. The preparation method of the imidazole-connected redox type imidazole covalent organic framework material comprises the following steps: respectively reacting a reactant 2, 7-di-tert-butylpyrene-4, 5, 9, 10-tetraketone monomer with 4, 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ' The preparation method comprises the following steps: mixing 4, 4 '-(pyridine-2, 4, 6-triyl) tribenzaldehyde and a tri (4-formylphenyl) amine monomer, adding a solvent and a catalyst, uniformly stirring, and reacting to obtain the redox type imidazole covalent organic framework material after the reaction is finished. The application comprises the following steps: adding the covalent organic framework, oxygen and the sacrificial agent into water, and reacting under the irradiation of visible light. The preparation method is green, environment-friendly, simple and easy to implement, the prepared material has good thermal stability, and efficient visible light photocatalysis preparation of hydrogen peroxide can be achieved; meanwhile, the catalyst can be recycled and has good photocatalytic stability.

The invention discloses a high-activity and high-thermal-stability MHET hydrolase mutant and application thereof. The invention provides a mutant protein of thermophilic carboxylesterase, which is shown as 1) or 2): 1) the protein shown as 1) is a protein obtained by mutating amino acid residues at the 130th site and the 171th site of wild thermophilic carboxylesterase shown as SEQ ID NO.2 or a sequence corresponding to the SEQ ID NO.2 and keeping other amino acid residues unchanged; (2) the protein is obtained by mutating amino acid residues at the 127th site, the 130th site and the 171th site of wild thermophilic carboxylesterase and keeping other amino acid residues unchanged. Experiments prove that the activity of the modified mutant for catalyzing MHET hydrolysis at the temperature of 50 DEG C is improved by 95 times compared with that of a wild type, and the modified mutant has higher enzyme activity and thermal stability and is the first enzyme capable of efficiently catalyzing MHET hydrolysis at the temperature of 50 DEG C at present.

The invention belongs to but not limited to the technical field of electrode materials, and particularly relates to a high-tap-density lithium nickel manganese oxide positive electrode material, a preparation method and a lithium ion battery, the chemical general formula of the high-tap-density lithium nickel manganese oxide positive electrode material is LiNi < 0.5-x > Mn < 1.5-y > M < x > N < y > O < 4 >, 0.1, 0 < = y < lt >; 0.1, M and N are doping elements and comprise one or more of Mg, Co, Al, Zr, W, Sb, Ta and Ti; the material is micron-sized spherical secondary particles formed by stacking and aggregating nano-sized octahedral primary particles, and is uniformly dispersed without agglomeration; the spherical secondary particles are formed by mixing spherical secondary particles with large and small particle size distribution, and the average particle size range of the large particles is 3lt; d < 50lt >; the average particle size range of the small particles is 1lt; d < 50lt >; 2 [mu] m.

The invention relates to a composite phase-change film based on liquid metal and PBO fiber and a preparation method thereof, and belongs to the technical field of phase-change material preparation, and the preparation method comprises the following steps: the composite phase-change film comprises a poly (p-phenylbenzobisoxazole) fiber (PBO) base material, a phase-change material and a heat-conducting filler, the phase-change material is composed of phase-change microcapsules (PM) which are prepared by taking polyurethane (PU) as a wall material and organic solid-liquid phase-change materials (OPCMs) as a core material through a Pickering emulsion polymerization method. The prepared PM has a core-shell structure, and leakage of OPCMs is effectively prevented. The PM and the PBO fiber network are combined, so that the dual packaging of the OPCMs is realized, and the leakage of the OPCMs is further prevented. Meanwhile, dispersion and interaction of the OPCMs in a PBO matrix are optimized, and formation of a network structure with a limited domain is promoted. The composite phase change film prepared by the invention has relatively high mechanical properties, remarkable heat conductivity, excellent and stable flexibility and excellent heat storage capacity.

The invention relates to a preparation method and application of an inner-rigid outer-soft core-shell structure silicon dioxide blocking agent for marine drilling fluid, and belongs to the field of deepwater oil and gas drilling. N-vinyl-2-pyrrolidone, dimethyl diallyl ammonium chloride, acrylamide and 2-acrylamide-2-methylpropanesulfonic acid are polymerized and grafted on the surface of nano silicon dioxide to form the silicon dioxide blocking agent with a core-shell structure and a rigid inside and a soft outside; by means of rigid plugging of a nano material and deformation filling flexible plugging of a high-molecular polymer, shale micro-nano pores are efficiently plugged with rigid inside and flexible outside, so that the stability of a well wall is maintained, meanwhile, secondary generation of hydrates is effectively inhibited, and the safety and efficiency of deepwater drilling are improved; the plugging agent provided by the invention reduces the demand on a large number of thermodynamic inhibitors, not only saves the cost, but also has the characteristic of environmental protection.

The invention provides a surface interface modified lithium-rich manganese-based positive electrode material and a lithium ion secondary battery. According to the invention, active oxygen substances such as O2, O2-, O-and oxygen polymer On-are absorbed and embedded into lattice gaps from the particle surface interface of the lithium-rich manganese-based positive electrode material under the driving of potential when the functional material is charged to a high voltage, and then the active oxygen is released when the functional material is discharged to a low potential, so that the active oxygen returns to the lithium-rich manganese-based positive electrode material again; and an active oxygen utilization reversible closed loop is formed. In the surface-interface modified lithium-rich manganese-based positive electrode material provided by the invention, the application of the surface functional material inhibits oxidation precipitation of lattice oxygen of the lithium-rich manganese-based positive electrode material in a high-voltage lithium removal state, and the positive electrode material can realize controllable oxygen reversible electrochemical deintercalation / intercalation at different potentials; and the cycling stability and the thermal stability of the material in a high-temperature and high-voltage environment are remarkably improved.

The invention provides a paraffin-based phase change microcapsule and a preparation method thereof. The preparation method comprises the following steps: S1, adding an acetic acid solution into a silane coupling agent to adjust the pH to be acidic, then adding nano aluminum oxide, carrying out ultrasonic treatment and water bath reaction, centrifuging to take a solid, and washing to be neutral to obtain a modified aluminum oxide aqueous solution; s2, adding an aqueous solution containing an emulsifier into the molten paraffin solution, and uniformly stirring in a constant-temperature water bath to obtain an emulsified solution; s3, slowly dropwise adding the modified aluminum oxide aqueous solution into the emulsified solution, and performing in-situ polymerization to obtain the paraffin-based phase change microcapsule. The paraffin-based phase change microcapsule obtained by dropwise adding the modified aluminum oxide aqueous solution into the emulsified solution through in-situ polymerization is appropriate in particle size and has the characteristics of low supercooling property, good heat storage property and high heat conductivity, and in addition, the paraffin core is tightly coated with the modified aluminum oxide shell layer, so that paraffin leakage can be effectively prevented.

The invention provides a temporary bonding adhesive and a preparation method and application thereof, and the preparation raw materials of the temporary bonding adhesive comprise the following components by weight: 60-80% of an organic solvent; 20-35% of base resin; 0.1 to 1% of tackifying resin; 0.1%-1% of an antioxidant; and 0.1-1% of a wetting leveling agent. The temporary bonding adhesive provided by the invention has the properties of high hardness, smooth film surface, high adhesive strength, high chemical corrosion resistance and the like, and can be widely applied to wafer processing.