1397 results about "Polymer solution" patented technology

The invention relates to the technical field of heat-conducting graphite materials, in particular to a POD precursor film, a POD-based graphite film and a preparation method of the POD precursor film, the POD-based graphite film and the preparation method of the POD precursor film. After the reaction is finished, obtaining an antioxidant modified aromatic polyoxadiazole polymer solution; the preparation method comprises the following steps: coating an antioxidant modified aromatic polyoxadiazole polymer solution with a wiped film, then carrying out solidification forming in a multi-stage coagulation bath, and finally neutralizing, washing and drying to obtain a POD precursor film; the coagulating bath is an aqueous solution of sulfuric acid and boron compounds and an aqueous solution of sulfuric acid. And carrying out carbonization treatment and graphitization treatment on the POD precursor film to obtain the POD-based graphite film. According to the preparation method, the boron element is cooperatively introduced into and out of the POD precursor film, so that the oxidation resistance of the graphite film is remarkably improved while the high thermal conductivity is maintained.

The invention discloses a method for improving the performance of a resistance reducing agent based on cyclodextrin solubilization modification and application, and belongs to the technical field of fracturing fluids. The method comprises the following steps: S1, preparing a mixed liquid from hydrophobic associated polymer dry powder and cyclodextrin; s2, stirring the mixed liquid, testing the particle size of the mixed liquid at the same time interval, and ending stirring after the particle size is reduced to a stable size, so as to obtain the hydrophobic associated polymer solution. The cyclodextrin polymer not only has a high-molecular effect, but also retains the inclusion ability of a cyclodextrin cavity, and has better inclusion performance under the condition of larger guest molecules. The hydrophobic association polymer is modified through a host-guest inclusion technology, the solubility of the hydrophobic association polymer is improved on the basis of guaranteeing the resistance reducing effect of the hydrophobic association polymer, and the prepared hydrophobic association polymer resistance reducing agent has the advantages of being fast in dissolution and good in shear resistance and resistance reducing effect.

The present application discloses a continuous dynamic and efficient devolatilization method for a polymer / volatile system based on high mass transfer interfaces, including the following steps: providing a dynamic single-screw devolatilizer, feeding a polymer solution to the devolatilizer, wherein the polymer solution includes polymer and volatile substances with small molecule weight, and the volatile substances include organic solvents, residual monomers, water or reaction by-products; conveying and compressing polymer materials by the screw downstream a devolatilization section, and extruding the polymer materials out of the dynamic single-screw devolatilizer directly; or providing a side-feeding extruder downstream of the devolatilization section and feeding plastic additives into a devolatilized polymer melt, and then melt blending the plastic additives with the devolatilized polymer melt at an end of the dynamic single-screw devolatilizer before exiting the dynamic single-screw devolatilizer.

The invention relates to the technical field of oil and gas field exploitation, and discloses a drag reducer for a multifunctional fracturing fluid and a preparation method thereof.The preparation method of the drag reducer for the multifunctional fracturing fluid comprises the steps that acrylic acid, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid and modified itaconic acid are added into deionized water, stirring and mixing are conducted, and the drag reducer for the multifunctional fracturing fluid is obtained. Nitrogen is introduced for 30-40 min to remove oxygen, then azobis (isobutylamidine) hydrochloride is added, the mixture is stirred to react for 48-72 h at the temperature of 45-50 DEG C, and a polymer solution is obtained; and directly and uniformly mixing the polymer solution, the compatilizer and the modified nano silicon dioxide, and reacting in a magnetic stirrer at 60-70 DEG C for 1.5-2 hours to obtain the drag reducer for the multifunctional fracturing fluid. The drag reducer has a good drag reduction effect, and the hydrophobicity, the temperature resistance, the salt resistance and the shear resistance are improved.

The invention belongs to the field of pharmaceutical preparations, and relates to a brexpiprazole long-acting microsphere and a preparation method thereof, and the preparation method comprises the following steps: (1) dissolving brexpiprazole and a degradable polymer in an organic solvent to obtain a drug-containing polymer solution as an oil phase; (2) mixing the drug-containing polymer solution with a polyvinyl alcohol solution through a microfluidic technology to obtain an oil-in-water emulsion; and (3) under a stirring condition, carrying out curing, washing and freeze drying on the oil-in-water type emulsion to obtain the brexpiprazole long-acting microspheres. By adjusting the volatilization stirring time when the O / W primary emulsion is formed, the final in-vitro release rate of the microspheres is adjusted, and the microspheres which are free of burst release and hysteresis period and are slowly released can be screened out. The brexpiprazole long-acting microsphere provided by the invention is simple in preparation process, easy to industrially amplify, high in encapsulation efficiency, large in drug loading capacity, uniform in microsphere particle size distribution, round in shape, good in flowability and good in needle passing property, is easier to inject, has an obvious slow release effect, and can be used for reducing the fluctuation of blood concentration and effectively improving the compliance of psychiatric patients.

The present disclosure pertains to methods for enhancing the properties of conventional Li / Al-LDH by integrating polymers to provide compositions comprising a Li / Al-LDH material and a polymer. The present disclosure further pertains to methods of using such polymer-modified-LDH to improve lithium adsorption and extraction performance. The disclosed methods can comprise incorporating the polymer during the precipitation reaction or by mixing the Li / Al-LDH product with a polymer solution under specific conditions. During the lithium extraction process, the disclosed compositions comprising a Li / Al-LDH material and a polymer can be used as an excellent lithium adsorbent to capture lithium ions from low-concentration lithium resources due to its improved physicochemical properties. The disclosed compositions comprising a Li / Al-LDH material and a polymer provides compositions for lithium extraction from low concentration resources, as well as expands the scope of lithium adsorbent material development.

The invention discloses a method for constructing a multicellular living body material by adopting a droplet bioreactor, which belongs to the crossing field of biological materials and microbial engineering, and comprises the following steps: (1) resuspending different cells in different polymer solutions to prepare degradable or phase-separable hydrogel particles containing cells; (2) dispersing the hydrogel particles in a cross-linkable hydrogel matrix to form a composite hydrogel; and (3) curing the composite hydrogel, and then carrying out degradation treatment to obtain the liquid cavity structure multicellular system bioreactor with spatial partition and dynamic interaction characteristics. According to the invention, ordered distribution and metabolism synergy of different microorganisms in space can be realized, controllable degradability and excellent mass transfer performance are realized, bacterial slow release and metabolite exchange can be maintained, and the method is suitable for long-term stable operation of a continuous flow reactor. The method has wide application prospects in the fields of green biological manufacturing, renewable energy source production, environmental restoration, biomedical engineering and the like.

Disclosed herein is a pressurized therapeutic composition configured to be stored in a valved container designed to maintain an inverse thermosensitive polymer foam composition under pressure and dispense the composition upon opening the valve thereof. After the composition is dispensed from the container the evaporation of an expanding component (e.g., compressed gas or volatile liquid) can cause the inverse thermosensitive polymer solution to foam. The reduced pressure produced from dispensing the inverse thermosensitive polymer solution can reduce its temperature so as to facilitate distribution in a more liquid foam form. The inverse thermosensitive polymer solution can undergo a reverse phase change from a liquid to a gel upon warming (e.g., once dispensed onto or into a body part).

The invention provides a preparation method of a two-dimensional high-strength coating material, which comprises the following steps: under the protection of inert gas, dissolving melamine and trimesoyl chloride as reaction monomers in a solution A, adding triethylamine as an acid-binding agent, and promoting amidation reaction through magnetic stirring; after the reaction is finished, washing with saturated saline solution and NaHCO3 to remove impurities, and then obtaining high-purity two-dimensional polymer powder through the steps of solution mixing, ultrasonic treatment, centrifugal separation and the like. And finally, dissolving polymer powder in the solution F to prepare two-dimensional polymer solutions with different concentrations, and coating the two-dimensional polymer solutions on the surface of a substrate pretreated by acetone and isopropanol to obtain a flat and compact coating film. The triethylamine is adopted as the acid binding agent, so that the purity and the reaction efficiency of the polymer are improved, the preparation controllability and the structural uniformity of the coating material are remarkably improved, and the high-performance coating requirements in the fields of machinery, chemical protection and the like are met.

The invention belongs to the technical field of membrane electrodes, and particularly relates to a hydrogen fuel cell catalyst layer slurry based on hydrophilic and hydrophobic regulation and a preparation method of a membrane electrode. The slurry of the catalyst layer comprises the following contents: the slurry of the PEM close to the cathode side comprises a Pt / C catalyst, deionized water, a perfluorosulfonic acid ionic polymer solution and isopropanol; the mass ratio, namely I / C ratio, of the ionic polymer to the carbon carrier is 0.8-1.2; the GDL cathode side slurry comprises a Pt / C catalyst, deionized water, a perfluorosulfonic acid ionic polymer solution, a PTFE aqueous solution (polytetrafluoroethylene aqueous solution) and isopropanol, and the mass ratio of the ionic polymer to the carbon carrier, namely I / C ratio, is 0.3-0.5. High hydrophilic ionomer content is reserved on the side, close to the cathode, of the PEM, proton conduction and catalyst active site wetting are guaranteed, the proportion of hydrophobic ionomers and hydrophobic materials is increased on the GDL side, a drainage channel is formed, liquid water is prevented from blocking gaps, then the performance of the membrane electrode is remarkably improved, and the interface contact resistance is stabilized to be 1.64-1.76 m omega (2.5 A / cm < 2 >).

The invention relates to a lithium ion battery and a preparation method thereof. The lithium ion battery comprises a positive pole piece, a negative pole piece and a gel electrolyte, the gel electrolyte is formed by polymerizing an electrolyte prepolymerization solution, and the mass percentages of a cross-linking agent, a monomer and an initiator in the electrolyte prepolymerization solution are A%, B% and C% respectively; a positive electrode material layer in the positive electrode plate is formed by coating the surface of a positive electrode current collector with positive electrode slurry; the positive electrode slurry comprises a fast ion conductor, and the mass percentage content of the fast ion conductor in the positive electrode slurry is X%; the lithium ion battery satisfies the following relational expressions: the formula 1: 5 < B / A < 10; in the formula 2, C / (A + B) is more than 0.005 and less than 0.02; formula 3: 1.7 < = (A + B + C) / X < = 5.5. According to the scheme provided by the invention, a high-performance organic-inorganic hybrid network can be constructed, and the cycle performance of the battery is remarkably improved while the thermal shock performance of the battery is improved.

The invention discloses an electrostatic ionization device and an array spinning ionization box, and relates to the field of textile processing machinery, the electrostatic ionization device comprises an ionization assembly, the ionization assembly is provided with a backflow groove with a top opening, and a metal wire which is horizontally arranged and can be externally connected with a power supply is arranged above the backflow groove; the reciprocating assembly comprises a liquid supply brush making contact with the upper surface of the metal wire and can drive the liquid supply brush to reciprocate along the axis of the metal wire and coat the surface of the metal wire with a polymer solution used for electrostatic ionization. The liquid supply assembly can store a polymer solution and convey the stored polymer solution to the liquid supply brush, and the backflow groove is communicated with the liquid supply assembly and can collect the polymer solution dripping in the process that the surface of a metal wire is brushed by the liquid supply brush and flow back into the liquid supply assembly. According to the electrostatic ionization device and the array spinning ionization box, the solution utilization rate can be increased, rapid replacement of multiple solution varieties can be achieved, raw material waste is reduced, and the production cost is reduced.

The invention belongs to the field of flexible piezoelectric polymer materials, and discloses a polyvinylidene fluoride based ferroelectric polymer and a preparation method thereof. The preparation method comprises the following steps: (1) adding an inorganic alkaline reagent into a polyvinylidene fluoride-trifluoroethylene ferroelectric polymer solution, carrying out dehydrofluorination and nucleophilic addition-elimination reaction to generate a polymer with an enol structure, and then washing, precipitating and purifying a reaction product; and (2) re-dissolving by using an organic solvent, then forming a film by using a tape casting method, and carrying out ketone-enol tautomerization reaction in the film forming process of the tape casting method to finally prepare the polyvinylidene fluoride based ferroelectric polymer film. According to the effective modification and preparation method disclosed by the invention, an enol structure is promoted to be converted into a more stable ketone structure through a ketone-enol tautomerization reaction by utilizing a high-temperature environment in a film forming process, so that C = O double bonds are introduced into a polymer chain, and the piezoelectric property of the polymer is remarkably enhanced.

The invention provides an oil-water separation mineralization net film as well as a preparation method and application thereof. The oil-water separation mineralization net film comprises an organic layer crosslinked on a grid substrate, the inorganic layer grows in the organic layer in an in-situ mineralization manner; the organic layer is a polymer layer formed by coating a polymer solution containing a cross-linking agent on the grid substrate for cross-linking; the inorganic layer is an inorganic mineral particle layer which grows on the surface of the organic layer in an in-situ mineralization mode. The mineralized net film for oil-water separation not only has excellent binding capacity with the grid substrate, but also has high chemical stability of acid resistance, alkali resistance and organic solvent resistance and excellent mechanical performance, and can be widely applied to oil-water separation under complex conditions.

The invention provides a preparation method and device of a stretchable conductive interface. The method comprises the following steps: pouring a stretchable polymer solution or a precursor mixture of silica gel into a gradient polytetrafluoroethylene mold on a horizontal table, and standing to form a stretchable polymer film with a gradient thickness; covering the surface of the stretchable polymer film with an electrode patterning mask, and depositing a conductive circuit on the surface of the stretchable polymer film through vacuum thermal evaporation or magnetron sputtering to form a microcrack gold conductive layer covering the surface of the stretchable polymer film, so as to complete electrode patterning and obtain a gradient gradient flexible electrode; and after one end, with the large thickness, of the stretchable polymer film of the gradient gradient flexible electrode is connected with a flexible printed circuit board FPCB, the surface of the gradient gradient flexible electrode is covered with a polymer insulating layer film with the modulus matched with that of the substrate for packaging protection, and preparation of the stretchable conductive interface is completed. Stress can be effectively dispersed, and the mechanical stability and durability of a connector are improved.

The invention belongs to the technical field of biomedical materials, and particularly relates to a multi-layer multifunctional hydrogel microsphere for diabetic wounds as well as a preparation method and application of the multi-layer multifunctional hydrogel microsphere. The preparation method comprises the following steps: firstly, synthesizing a chitosan derivative with proper amino and aldehyde group contents, oxidized macromolecules and modified chitin; then preparing photocuring hydrogel microspheres by utilizing a microfluidic technology, and sequentially immersing the photocuring hydrogel microspheres into an oxidized polymer solution, a modified chitin solution, a tannic acid solution and a metal salt solution, so as to construct the hydrogel microspheres with a multifunctional layer structure. The invention further provides specific application intervals of parameters such as solvents used by various solutions, concentration ranges and soaking time. The preparation method provided by the invention has expansibility and universality, various types of microspheres can be constructed for sequential release of bioactive substances, and the requirements of tissue repair are met.

The invention provides a high-modulus low-friction heterogeneous gel material as well as a preparation method and application thereof. The heterogeneous gel material is obtained through the steps that hydrophilic monomers are subjected to free radical polymerization in a hydrophobic polymer solution to obtain a heterogeneous polymer with a hydrophobic phase and a hydrophilic phase in a continuous phase separation structure, then the heterogeneous polymer is swelled, and the mass fraction of the hydrophobic phase in the heterogeneous polymer is 20-50%; the molecular weight of the hydrophobic polymer is 8000 to 50000 Da; wherein the tensile modulus of the heterogeneous gel material is 10 MPa-1 GPa, and the friction coefficient of the heterogeneous gel material under the contact pressure of 1 to 50 MPa is 0.005 to 0.03. The heterogeneous gel material has a bicontinuous phase separation structure, so that the technical problem that the mechanical property and the lubricity of a traditional hydrophilic material are mutually restricted and are difficult to balance can be effectively solved.

The invention discloses a high-viscosity polymerization solution devolatilization system. The high-viscosity polymerization solution devolatilization system comprises a first-stage flash heater, a first-stage flash tank distributor, a first-stage flash tank, a second-stage flash heater, a second-stage flash tank distributor, a second-stage flash tank, a third-stage flash tank distributor and a third-stage flash tank. The invention also provides a high-viscosity polymerization solution devolatilization process which is operated in the system. According to the high-viscosity polymerization solution devolatilization system and process provided by the invention, through static flash devolatilization, dynamic flash does not need to be introduced, and the energy consumption is relatively low; in the high-viscosity polymerization solution devolatilization process provided by the invention, the glue solution content in the polymer solution at the liquid phase outlet of the first-stage flash tank is 50-75% wt, the glue solution content in the polymer solution at the liquid phase outlet of the second-stage flash tank is 85-93% wt, the glue solution content in the polymer solution at the liquid phase outlet of the third-stage flash tank can reach 99.9% wt or more, and the devolatilization efficiency is high.

The invention discloses a high-solid-content MIL-101 (Fe) / PIM-1 mixed matrix membrane and a preparation method thereof, and belongs to the technical field of gas separation membranes. The preparation method comprises the following steps: firstly, dissolving an iron source in a PIM-1 polymer solution to form a homogeneous membrane casting solution; forming the obtained membrane casting solution, and removing the solvent to obtain a PIM-1 / Fe (II) composite substrate containing Fe (III); then, the substrate is alternately immersed in a terephthalic acid methanol solution and a ferric salt methanol solution, and MIL-101 (Fe) is generated in the polymer matrix through in-situ limited crystallization by layer-by-layer limited crystallization. According to the method, the problem of interfacial compatibility between the MOF filler and the polymer matrix is effectively solved, and high loading capacity (up to 52.9 wt.%) of MIL-101 (Fe) is realized without agglomeration. Meanwhile, the membrane has excellent COplasticizing resistance and long-term operation stability, and has a wide application prospect in the fields of carbon capture and the like.

The present invention generally relates to a process for fabricating a reduced graphene oxide (rGO)-based antifouling marine coating is disclosed. The process begins with preparing a dispersed graphene oxide solution, followed by chemical reduction using hydrazine hydrate at 90-95° C. for 3 hours to form a dispersed rGO solution. This solution is then washed, filtered, and sonicated for 6 hours to ensure stability. A polymer solution is prepared by dissolving 40-50 wt % epoxy resin in acetone at 50° C. The antifouling composite is then formed by combining the rGO solution, 10-15 wt % zinc oxide nanoparticles, and 1-5 wt % carbon nanotubes with the polymer solution, followed by 6 hours of sonication at room temperature. Finally, the resulting composite material is applied to a substrate as a coating using spraying, brushing, dipping, or spin coating. This coating offers a promising solution for preventing biofouling on marine structures.

The invention belongs to the technical field of marine organism fouling protection, and particularly discloses a self-repairing coating for preventing biological fouling and a preparation method and application thereof, and the preparation method comprises the following steps: S1, adding polydimethylsiloxane and aliphatic diisocyanate into an organic solvent according to a molar ratio of 1: (1.0-3.0), continuously stirring for more than 0.5 h, and standing to prepare an organosilicon polymer solution; the polydimethylsiloxane is aminopropyl double end capped polydimethylsiloxane, and the polydimethylsiloxane is an aminopropyl double end capped polydimethylsiloxane; s2, adding methyl silicone oil into the organic silicon polymer solution, and continuously stirring for more than 0.5 hour to prepare a transparent organic silicon prepolymer; and S3, uniformly coating the surface of a substrate with the prepolymer prepared in the step S2, and standing to obtain the self-repairing coating for preventing biological fouling. Complete covering and damage self-repairing of a lubricating layer on the surface of the coating can be achieved, attachment and growth of fouling organisms are effectively prevented, and the coating is endowed with long-acting antifouling performance.

The invention belongs to but is not limited to the technical field of petroleum engineering, and particularly relates to a shale reservoir polymer fracturing fluid retention characteristic analysis method and system, and the method comprises the following steps: S1, carrying out a displacement experiment by using polymer solutions with different molecular weights and concentrations; s2, the retention condition of polymers in the rock core before and after displacement is observed through a micron CT and scanning electron microscope technology; and S3, analyzing the influence of the polymer solutions with different molecular weights and concentrations on the retention characteristics in the shale reservoir. The invention aims to carry out a displacement experiment on the rock core by using polymer solutions with different molecular weights and concentrations, and then observe and compare the polymer solutions of the rock core before and after displacement by using equipment such as a CT scanner and an electron microscope, so as to obtain the retention and migration conditions of the polymer in the hole seam of the rock core. The retention characteristics of fracturing fluid polymer molecules in a microporous structure and a matrix are studied, so that a correct polymer molecular weight range is provided for reservoir transformation, fracturing fluid reservoir damage is reduced, and the fracturing yield increasing effect is finally improved.

The invention discloses a mixed matrix membrane for efficient oxygen and nitrogen separation and a preparation method and application thereof. The mixed matrix membrane comprises a polymer continuous phase and an MOF filler uniformly dispersed in the polymer continuous phase, the MOF filler can separate nitrogen and oxygen, and the surface of the MOF filler is modified by the silane coupling agent, so that the MOF filler is well compatible with a polymer, and the oxygen-nitrogen separation effect is improved. The polymer solution and the MOF filler dispersion liquid are mixed, the mixed matrix membrane is prepared through the non-solvent induced phase separation method, and the method has the advantages of being simple in reaction condition, high in efficiency, easy to amplify and the like and has wide engineering prospects.

The invention relates to a method for preparing a grid line of a battery piece, which is characterized in that a layer of polymer solution capable of flowing and extending is coated on a mold, and the surface of the mold is provided with a convex structure completely corresponding to a pattern of the grid line of the battery piece. After the polymer solution is cured, a coating with a groove structure is formed, and the grooves are filled with conductive paste. And then, transferring the polymer coating coated with the conductive slurry to the upper surface and the lower surface of the battery piece by adopting a transfer printing technology, and realizing accurate transfer printing of the grid line by accurately regulating and controlling transfer printing parameters. A photocuring technology can be introduced in the transfer printing process, and the conductive slurry is rapidly cured through ultraviolet irradiation. A high-precision mold is adopted to ensure the precision of the size and the shape of the grid line, the functional requirements of different grid line areas are met through formula adjustment and a step-by-step coating technology, the traditional preparation process is simplified, the production efficiency is improved, the production cost is reduced, the electrode structure is optimized, and the production cost is reduced. And the current collection efficiency and the overall performance of the photovoltaic cell are improved.

The invention provides a double-layer coated porous silicon carbon negative electrode material and a preparation method thereof.The preparation method comprises the steps that a carbon precursor and a doped precursor are evenly mixed, inert gas is introduced into a chemical vapor deposition furnace, the temperature is adjusted to 400-500 DEG C, meanwhile, silicon source gas is introduced, the reaction time is controlled to be 500-1000 minutes, and a porous silicon carbon framework is obtained, the doped precursor comprises a silicon source material; heating the porous silicon carbon skeleton to 450-550 DEG C, introducing oxygen-containing gas, and reacting for 200-800 minutes to obtain an oxygen-silicon layer deposited on the surface of the porous silicon carbon skeleton; dispersing the porous silicon carbon skeleton with the oxygen silicon layer in a mixed solvent, adding a modified coupling agent and a lithium salt, stirring for 1-5 hours at room temperature, adding a polymer solution after stirring, stirring for 1-5 hours at room temperature, generating a polymer layer on the oxygen silicon layer, and washing and drying to obtain the double-layer coated porous silicon carbon negative electrode material. Therefore, the cycle performance of the negative electrode material is effectively improved.

The invention belongs to the technical field of alkaline electrolyzed water, and relates to a preparation method of an LDH / PSF / PP composite anion exchange membrane, which comprises the following steps: step 1, uniformly dispersing PSF polymer molecules in a polar organic solution to form a PSF polymer solution; step 2, preparing LDH with a high specific surface area, and uniformly dispersing the LDH into the PSF polymer solution to prepare a membrane casting solution; 3, blade-coating the prepared membrane casting solution on a PP support net to form a serous membrane, and then transferring the composite membrane to a drying oven for a pre-evaporation process; step 4, transferring the pre-evaporated composite membrane into a coagulating bath for phase inversion, and curing the PSF in the coagulating bath due to solvent precipitation so as to form a solid composite membrane; and step 5, soaking the prepared solid composite membrane in deionized water to remove the residual solvent. The preparation method of the LDH / PSF / PP composite anion exchange membrane has the advantages of low surface resistance, high gas barrier property, high mechanical strength and capability of realizing large-scale preparation, and is a preparation method of the LDH / PSF / PP composite anion exchange membrane with relatively high innovativeness.

Disclosed herein are a high-molecular artificial heart valve and a preparation method therefor, relating to the technical field of medical instruments. The high-molecular artificial heart valve comprises a frame, a skirt arranged on the surface of the frame, and valve leaflets bonded with the skirt. The preparation method therefor comprises the following steps: after the skirt is prepared on the frame, arranging a part of the valve leaflets on the surface of at least a part of the edge of the skirt, or connecting the edges of the valve leaflets with the at least a part of the skirt, and then bonding the valve leaflets with the edge of the skirt by means of interface microtreatment. The interface microtreatment is achieved by means of a polymer solution that bonds the valve leaflets with the edge of the skirt or by utilizing thermal bonding between the valve leaflets and the edge of the skirt. The valve prepared by the method has the advantages of uniform structure and high strength, effectively improving the production quality of the valve.

The invention discloses a method for preparing a transdermal microneedle based on gallium-based liquid metal, which comprises the following steps: (1) heating the gallium-based liquid metal at a temperature higher than the melting point of the liquid metal, so that the gallium-based liquid metal is completely molten into a liquid state; (2) sucking the liquid metal preheated in the step (1) by using a microsyringe or a pipettor, and quickly injecting the liquid metal into a microneedle mold, so that the liquid metal is spread and completely covers a cavity of a needle tip in the mold; (3) transferring the mold in the step (2) into a constant-temperature vacuum box, and decompressing and degassing under vacuum; in the degassing process, the degassing temperature enables the liquid metal to be kept in a flowing liquid state all the time, and vacuumizing is conducted till the pressure is not higher than 10 Pa; the degassing time is not less than 5 hours; (4) continuously injecting the preheated gallium-based liquid metal or a degradable polymer solution into the mold to form a substrate of the microneedle; and (5) transferring the mold in the step (4) to a temperature far lower than the melting point of the liquid metal, and freezing and forming to obtain the transdermal microneedle.

The invention relates to the field of optical thin films, in particular to a preparation method of an optical diffusion film. A preparation method of an optical diffusion film comprises the following steps: uniformly mixing a curing agent and polydimethylsiloxane, curing, and then carrying out oxygen plasma treatment and room temperature aging treatment to obtain a polydimethylsiloxane flat plate; dissolving PET particles and PMMA particles in a solvent to obtain a polymer solution; and placing a polydimethylsiloxane flat plate above the polymer solution, and standing to obtain the optical diffusion film. According to the application, PMMA is used as a high glass transition temperature component to be blended with PET, so that the overall glass transition temperature of a blending system is improved, and the practicability of the optical diffusion film in a high-temperature environment is improved; strong scattering is provided through the refractive index difference between air holes and a polymer phase, and a refractive index gradient is formed by using the refractive index difference between PET and PMMA, so that a secondary scattering interface is formed, and light absorption is reduced and high transmittance is maintained while high haze is ensured.

The preparation method of the CO2 thickening-downmixing-tracing nano carbon needle comprises the following steps: step 1, modifying a nitrogen-doped activated carbon quantum dot by adopting a silane coupling agent to obtain a modified activated carbon quantum dot; 2, mixing methyl silicone oil, a silane coupling agent and a thickening functional monomer to obtain a mixture, and activating; adding a catalyst and fully reacting to obtain a fluorine-containing siloxane polymer; 3, mixing the activated carbon quantum dots obtained in the step 1 and the fluorine-containing silane polymer solution obtained in the step 2, and fully reacting to obtain the CO2 thickening-downmixing-tracing nano carbon needle; according to the nano carbon needle, the viscosity of supercritical carbon dioxide is increased, the miscible phase pressure is reduced, meanwhile, in-situ emulsification tackifying can be carried out in high-water-content and high-permeability pores, and CO2 pressure driving-tracing-burying integration of an oil and gas field can be achieved, so that a win-win mode of green low-carbon development and economic benefits is constructed.