994 results about "Coupling reagent" patented technology

The invention relates to the technical field of preparation methods of polypeptide drugs, and provides a solid-phase preparation method of tirpotide, which comprises the following steps: by taking amino resin as initial resin, sequentially coupling amino acid and small-fragment peptide according to an amino acid sequence of the tirpotide by using a solid-phase synthesis method to synthesize tirpotide resin; and cracking and purifying the tilpotide resin to obtain a pure tilpotide product. Wherein the small fragment peptide is 1-4 tetrapeptide fragment Boc-Tyr (tBu)-Aib-Glu (OtBu)-G1y-OH, 5-6 dipeptide fragment Fmoc-Thr (tBu)-Phe-OH, 7-8 dipeptide fragment Fmoc-Thr (tBu)-Ser (tBu)-OH, 10-11 dipeptide fragment Fmoc-Tyr (tBu)-Ser (tBu)-OH, 12-13 dipeptide fragment Fmoc-Ile-Aib-OH, 17-18 dipeptide fragment Fmoc-Lys (AEEA-AEA-gamma-Glu (alpha-OtBu)-Ecosanoic acid (mon-tBu), 20 side chain peptide Fmoc The coupling agent coupling the amino acid and the small fragment peptide is selected from the group consisting of Oxyma and DIC, TPTU and TMP or COMU and DIEA. The crude product of the tirpotide prepared by the method disclosed by the invention is high in yield and high in purity.

The invention relates to the technical field of epoxy molding compounds, in particular to a low-shrinkage and high-heat-resistance epoxy molding compound and a preparation method thereof. The low-shrinkage and high-heat-resistance epoxy molding compound is prepared from the following raw materials in parts by weight: 6 to 8 parts of epoxy resin, 3 to 7 parts of phenolic resin, 80 to 90 parts of filler, 0.6 to 1 part of modifier, 0.1 to 0.5 part of accelerant, 0.2 to 0.4 part of coupling agent, 0.3 to 0.8 part of flexibilizer, 0.2 to 0.4 part of release agent, 0.2 to 0.4 part of coloring agent and 0.3 to 0.5 part of flame retardant, the modifier is a mixture of 1-phenyl-5-mercaptotetrazole and 5-aminotetrazole according to a weight ratio of 5: (1 to 5); the prepared epoxy molding compound has the characteristics of low shrinkage and high heat resistance.

The invention relates to a degradable filter element and a preparation method thereof, and belongs to the technical field of PLA filter elements. The degradable filter element is arranged between an atomizing element shell and a metal heating wire, a plurality of capillary holes are formed in the degradable filter element and used for being filled with tobacco tar, and the degradable filter element is prepared from a degradable composite material through melt spinning. The degradable composite material comprises the following components: polylactic acid and modified silicon dioxide, wherein the modified silicon dioxide is prepared by taking nano silicon dioxide, a silane coupling agent, ferulic acid, amino acid and copper chloride as raw materials, the silicon dioxide is organically modified, so that the dispersity of the silicon dioxide in a polylactic acid system is improved, the interface binding force of the silicon dioxide is improved, and the mechanical property of a polylactic acid material is improved; various antibacterial components are introduced, so that the antibacterial property of the polylactic acid material can be effectively improved.

The present invention uses commercially available 3-aminopropylsilane coupling agent, diallylamino polyether acrylate, and an alkylating agent, or γ-propanesultone, or γ-butyrolactone as raw materials, and through an aza-Michael addition reaction and a quaternization reaction, a multifunctional silane coupling agent containing one or more quaternary ammonium cations, or sulfobetaine, or carboxybetaine in its molecular structure is prepared, which is used for the surface modification of bioactive glass, and the bioactivity, antibacterial and antifungal properties, and hydrophilicity enhancement effects after the surface modification of bioactive glass are obtained.

The invention belongs to the technical field of organic electro-oxidation electrode materials, and particularly relates to a fullerene modified transition metal hydroxide nano array material as well as a preparation method and application thereof. A transition metal hydroxide nano array grows in situ on a current collector through solvothermal reaction, surface amino modification is achieved by means of grafting of a silane coupling agent with amino, and finally the transition metal hydroxide nano array material with the surface modified by fullerene is obtained through addition reaction of amino and fullerene carbon-carbon double bonds. The strong electron-withdrawing capability of the fullerene is beneficial to optimizing the surface electron structure of the material, so that the intrinsic catalytic activity is improved; meanwhile, fullerene can promote adsorption and enrichment of an organic substrate on the surface of the material through a conjugated pi bond, a hydrophobic effect and the like, so that the mass transfer efficiency is improved. Benefited from the lifting mechanism, the obtained nano array material has the advantages of high electrocatalytic activity and high mass transfer efficiency, and can be widely applied to a series of organic electrooxidation reactions.

The invention belongs to the technical field of environmental protection, and provides a preparation method of an imine-modified functionalized mesoporous magnetic silicon dioxide nano material. The method comprises the following steps: synthesizing Fe3O4 magnetic nanoparticles in a Fe < 2 + > / Fe < 3 + > alkaline hydrolysis system through a coprecipitation method; then coating the magnetic nanoparticles with an amorphous silicon dioxide layer by taking TEOS (tetraethoxysilane) as a silicon source by adopting a sol-gel method, so as to prepare magnetic silicon coated nanoparticles; the prepared nano-particles are subjected to secondary silicon coating guided by a cetyl trimethyl ammonium bromide (CTAB) mesoporous template agent, and mesoporous magnetic silicon nano-particles are formed after calcination; and finally, carrying out surface amination modification on the mesoporous magnetic silicon nano-particles by utilizing an amino silane coupling agent, and then carrying out condensation reaction on the mesoporous magnetic silicon nano-particles and various aldehyde derivatives to construct imine bonds, so as to obtain the imine-modified functionalized mesoporous magnetic silicon dioxide nano-material. The imine-modified functionalized mesoporous magnetic silicon dioxide nano-material formed by the invention has the characteristics of efficient adsorption, rapid magnetic recovery and excellent environmental stability, and can effectively remove polystyrene micro-plastics and organic pollutants in a water body.

The invention relates to a preparation method and application of high-temperature-resistant organic modified bentonite. According to the method, three organic modifiers of long-chain quaternary ammonium salt, amide and a silane coupling agent are compounded to modify bentonite, and the problem that a single modifier is easy to decompose at high temperature is solved through the synergistic effect of physical intercalation, chemical crosslinking and interface bonding; and secondly, a three-dimensional stable structure is constructed by adding nano silicon dioxide and a composite modifier, so that the high temperature resistance and dispersion stability of the modified bentonite are further enhanced. According to the invention, the requirements of deep well and ultra-deep well drilling fluids on the temperature resistance and rheological property of the treating agent can be met, and the ultra-deep well drilling fluid which can tolerate the high temperature of 250-300 DEG C, and is low in filter loss and good in dispersion stability can be obtained.

The invention discloses a polyamine cross-linked network structure with high stability and a preparation method and application thereof, the structure takes an inorganic porous material as a carrier, the inorganic porous carrier and polyamine are cross-linked by using a silane coupling agent, and a cross-linking agent is introduced to cross-link polyamine molecules so as to form a solid adsorbent. The adsorbent still has more than 95% of adsorption capacity after 50 times of adsorption cycles, the desorption enthalpy is in the range of 50-80 kJ / mol, the regeneration energy consumption is in the range of 1.5-2.0 GJ / ton-CO2, and the high-stability and low-energy-consumption CO2 trapping characteristic enables the adsorbent to have large-scale application potential.

The present invention provides a multifunctional silane coupling agent, which is prepared from commercially available 3-aminopropylsilane coupling agent, acryloxy polyetheramine, and one of an alkylating agent, polyether sulfonate, γ-propane sultone or γ-butyrolactone through Michael addition reaction and quaternization reaction. The multifunctional silane coupling agent is a new variety carrying zwitterions, quaternary ammonium cations and polyether chains, enriching the functions and application scope of silane coupling agents. It can endow some modified materials with surface hydrophilicity, conductivity, antibacterial, antifogging, antifouling, biocompatibility, anticoagulant and wet lubrication properties, etc. at the same time.

The invention provides a polyimide multilayer composite membrane material as well as a preparation method and application thereof, and belongs to the technical field of gas separation. According to the method, through collaborative design of a functional support layer, a gradient MOF layer and an ultrathin selection layer structure, the problems of support layer pore seepage, MOF agglomeration, weak interface bonding and the like in an existing composite membrane material are solved. The preparation method comprises the following steps: firstly, carrying out electrostatic spinning on a polyamide acid glue solution, and synchronously introducing dopamine by adopting a chemical imidization method to prepare a functionalized polyimide fiber membrane containing hydroxyl and amino on the surface, so that the mechanical property of a supporting layer and the MOF anchoring capability are remarkably improved; growing MOF layers with different particle sizes on the surface of the fiber membrane by regulating and controlling the concentration gradient of ligand / metal salt and the reaction time, and passivating through a silane coupling agent after each step of growth so as to avoid heterogeneous nucleation and construct a gradient structure; after the MOF gradient layer is subjected to Ar plasma pretreatment to introduce hydroxyl, the ultrathin polyamide selection layer is formed by utilizing interfacial polymerization of fluorine-containing acyl chloride and a macrocyclic amine monomer, and the ultrathin polyamide selection layer is suitable for gas separation work.

The invention provides a preparation method of a Janus material for simultaneous screening of protein phosphorylation and palmitoylation modification, and belongs to the technical field of magnetic material synthesis. The method comprises the following steps: firstly, preparing MCeO2; the preparation method comprises the following steps: mixing MCeO2, hexadecyl trimethyl ammonium bromide and ammonia water to obtain a mixed solution, adding 1, 2-bis (triethoxysilane) ethane into the mixed solution for reaction to obtain a product, and dispersing the product into an NH4NO3 solution for reflux reaction to obtain Janus MCP; the preparation method comprises the following steps: reacting Janus MCP with a silane coupling agent, dissolving aminated Janus MCP and 4-ethylene sulfonyl benzoic acid in a buffer solution containing EDC and NHS, and reacting to obtain the Janus material. The preparation method is reliable, the material performance is stable, and the enrichment efficiency of the magnetic Janus on target peptide fragments (phosphorylated peptide fragments and palmitoylated peptide fragments) is remarkably improved.

The invention discloses a preparation method of a multifunctional group synergistic modified aluminum silicate nanofiber membrane, which comprises the following steps: modifying aluminum silicate nanofiber by using an amino silane coupling agent to obtain aminated aluminum silicate nanofiber; grafting a polyamino compound to the surface of the aminated aluminum silicate nanofiber by utilizing the cross-linking effect of 1, 3-dichloropropanol through a substitution reaction of amino and chlorine, so as to obtain a multifunctional aluminum silicate nanofiber; 2-butenal is modified on the surface of the multi-functionalized aluminum silicate nanofiber by utilizing an ammonia-aldehyde condensation reaction, so that the multi-functionalized aluminum silicate nanofiber rich in double bonds is obtained; carrying out cross-linking polymerization by taking itaconic acid as a monomer and the multi-functional aluminum silicate nanofiber rich in double bonds as a cross-linking agent, then carrying out suction filtration to form a membrane, and drying to obtain the multi-functional synergistic modified aluminum silicate nanofiber membrane with the gram weight not exceeding 15g / m < 2 >. According to the invention, high-efficiency adsorption of heavy metals is realized, and the problem that aluminum silicate nanofibers are not easy to recover is solved.

The invention relates to the technical field of wastewater treatment, in particular to a multistage composite adsorbent for treating petrochemical wastewater and a preparation method thereof.The preparation method comprises the steps that S1, plant straw powder and 3-aminopropyltriethoxysilane are subjected to a constant-temperature reaction, and aminated plant straw is obtained; s2, carrying out hydrothermal reaction on the aminated plant straw and a cerium nitrate solution to obtain functionalized plant straw; s3, the halloysite nanotubes, glutaraldehyde and the functionalized plant straw are stirred for a reaction, high-temperature carbonization is conducted after the reaction is completed, and composite biochar is obtained; s4, carrying out a reaction on the composite biochar and an amino silane coupling agent to obtain aminated composite biochar; s5, calixarene, toluene diisocynate and the aminated composite biochar are subjected to a reaction, and the multi-stage composite adsorbent is obtained. According to the technical scheme, the comprehensive adsorption capacity and removal efficiency of various organic pollutants in the petrochemical wastewater are improved, and the defect that a traditional adsorbent is poor in selectivity is overcome.

The invention belongs to the technical field of nano magnetic beads, and relates to a carboxyl nano magnetic bead and application thereof in DNA capture and DNA release. The invention discloses a preparation method of carboxyl nano magnetic beads, which comprises the following steps: dissolving iminodiacetic acid in a sodium hydroxide solution, stirring in an ice bath, dropwise adding a silane coupling agent, carrying out a first heating reaction, cooling in the ice bath, dropwise adding the silane coupling agent again, carrying out a second heating reaction, and cooling in the ice bath to obtain a carboxyl silane coupling agent; and dispersing the ferroferric oxide / silicon dioxide hydroxyl magnetic compound and a carboxyl silane coupling agent in an organic solvent, and stirring for reaction to obtain the carboxyl nano magnetic beads. The carboxyl nano magnetic bead is a nano-scale magnetic bead, is large in specific surface area, good in suspension property and not easy to settle, and has multiple sites for DNA binding; the method can be used for effectively extracting DNA ladders and cfDNA in nucleic acid capture and nucleic acid release.

The invention relates to a PPR antibacterial pipeline and a preparation method thereof, and belongs to the technical field of pipeline processing. The sea-buckthorn extract is used as an auxiliary medium, green synthesis of the silver nanoparticles can be promoted, use of traditional toxic reducing agents and stabilizing agents is avoided, natural active ingredients contained in the sea-buckthorn extract and the silver nanoparticles generate a synergistic effect, the antibacterial efficiency is remarkably enhanced, and the dosage and biotoxicity of the silver nanoparticles are reduced. Meanwhile, the nano silicon dioxide is added, so that the coating can be kept stable in a high-temperature environment. The carboxymethyl chitosan endows the pipeline with excellent antibacterial performance, and forms a synergistic effect with the silver nanoparticles, so that the antibacterial ability of the pipeline is further enhanced. Through the modification of the silane coupling agent KH560, the interface bonding force between the nano silicon dioxide and carboxymethyl chitosan and the interface bonding force between the nano silicon dioxide and the main component PPR of the pipeline are enhanced, so that the reinforcing agent can be more uniformly and stably dispersed in a PPR matrix, and the overall performance of the pipeline is improved.

The invention belongs to the field of separation membranes, and particularly relates to a preparation method of a reverse osmosis membrane. Comprising the following steps: a) coating a water phase solution containing multifunctional amine on the surface of a supporting layer of a base membrane, then coating an oil phase solution containing multifunctional acyl halide, and drying to form a polyamide separation layer on the surface of the supporting layer to obtain a nascent state membrane; b) soaking the nascent state membrane in an alkaline solution with the pH value of 9-12, and then rinsing to obtain a semi-finished membrane; c) coating a post-treatment solution containing polyvinyl alcohol, polydimethylsiloxane and an amino silane coupling agent on the surface of the polyamide separation layer of the semi-finished product membrane, and drying; d, the membrane treated in the step c is soaked in a 3-chloro-2-hydroxypropyl trimethyl ammonium chloride aqueous solution for quaternization reaction and dried, and the reverse osmosis membrane is obtained.The reverse osmosis membrane prepared through the method has good permeability, hydrophilicity, pollution resistance, antibacterial property and washing resistance.

The invention discloses a modified mesoporous silica adsorbent as well as a preparation method and application thereof, and relates to the technical field of porous material preparation. The preparation method of the modified mesoporous silica adsorbent provided by the invention comprises the following steps: hydrolyzing a silicon source in a solution containing a template agent to form a preliminary framework of silica, then adding a silane coupling agent containing at least one of sulfydryl, sulfonyl and amino, carrying out a hydrothermal reaction at 60-120 DEG C, and removing the template agent to obtain the modified mesoporous silica adsorbent. The modified mesoporous silica adsorbent capable of selectively adsorbing zirconium and hafnium can be obtained. The modified mesoporous silica adsorbent prepared by the method is used for adsorbing and enriching zirconium and hafnium ions, the adsorption capacities of 6.23 mg / g and 5.95 mg / g or above can be obtained respectively, the adsorption capacity is excellent, and the adsorbent can reach adsorption equilibrium within 10 min and is excellent in adsorption rate.

The invention discloses a recyclable biochip stationary phase as well as a preparation method and application thereof, and belongs to the field of biochips. The preparation method of the biochip stationary phase comprises the following steps: (1) activating a glass slide by adopting plasma, and then putting the glass slide into a silane coupling agent solution to react, so that a silane coupling agent is covalently bound with the glass slide to obtain a functionally modified biochip; and (2) combining the 5'end modified single chain oligo with the functionally modified biochip to obtain the biochip stationary phase. The biochip stationary phase disclosed by the invention is low in cost, excellent in physicochemical property, good in stability and tolerance and capable of adapting to a complex environment; more importantly, the method can be recycled, the resource utilization rate is increased, the pollution is reduced, and the method has huge application potential in the leading technical field of DNA synthesis by an enzyme method and the like.

The invention discloses a transparent super-hydrophobic cultural relic protection material and a preparation method thereof.The method comprises the steps that firstly, a hydrolyzed silane coupling agent is grafted to the surface of silicon dioxide, then amino of the hydrolyzed silane coupling agent reacts with carboxyl of chain fatty acid, chain alkyl is grafted to the surfaces of silicon dioxide particles, and the transparent super-hydrophobic cultural relic protection material is obtained. The prepared material has excellent super-hydrophobicity, the contact angle of water drops on the surface of a coating is large, the rolling angle of the water drops on the surface of the coating is small, the water drops are difficult to stay on the surface of the coating, and therefore water permeation is effectively prevented. Meanwhile, due to the transparency of the silicon dioxide particles and the chain fatty acid, the coating can keep high transparency, and the original color and pattern of the cultural relic cannot be shielded or changed. The silane coupling agent serves as a bridge for connecting the silicon dioxide particles and the chain fatty acid, the chemical bonding effect in the coating can be enhanced, the coating is not prone to aging and cracking, the material has the advantages of being good in high temperature resistance and ultraviolet light resistance, and therefore the preservation life of the cultural relics is prolonged.

An adsorbent composition comprising: a plurality of particles of an acid-activated clay with a predetermined particle size. Each particle may have a surface comprising metal oxides or metal hydroxides and each particle may have a surface modified by coupling the metal oxides to ligands comprising amino-silane coupling agents configured to adsorb impurities. Each amino-silane coupling agents may comprise an alkoxysilane group and an amine group. The alkoxysilane group may couple to the metal oxide or metal peroxide of each particle. The adsorbent composition may comprise the amino-silane coupling agent and the acid-activated clay with a wight ratio between 2:2 and 3:1 (the acid-activated clay: the amino-silane coupling agent). The acid-activated clay may comprise a plurality of pore with a predetermined diameter formed between particles.

The invention discloses a powder material for cosmetics and a preparation method thereof, and relates to the technical field of cosmetic raw materials, and the preparation method comprises the following steps: S1, compounding mica powder and pearl powder; s2, co-modifying a surface silicon source and a zinc source; s3, a silane coupling agent KH560, amino silicon oil and Meso-tetramethyl-meso-tetra (p-aminophenyl) calix [4] pyrrole are adopted for secondary modification. The powder material for cosmetics disclosed by the invention is good in hydrophobicity, excellent in skin feeling and sufficient in dispersity and stability.

The invention relates to an antistatic plastic film and a preparation method thereof, and belongs to the technical field of polymeric membrane materials, the antistatic plastic film is composed of a PET base film and an antistatic coating formed by curing an antistatic coating, the antistatic coating comprises the following components in parts by weight: 100 parts of organic silicon resin, 12-18 parts of an antistatic agent, 0.8-1.1 parts of a dispersing agent, 0.4-0.6 part of a bridging agent, 0.15-0.2 part of a flatting agent and 55-60 parts of a solvent, according to the antistatic agent, lamellar graphene is used as an electrostatic charge release matrix, a silane coupling agent KH-550 is used for introducing amino to the surface of a lamellar layer for modification, methyl chloroacetate and the amino grafted to the lamellar layer are used for substitution, finally, methyl iodide and a substituted amine compound are subjected to quaternization reaction, quaternary ammonium cations are introduced to the surface of the graphene lamellar layer, and the antistatic agent is obtained. And a continuous current collecting layer is formed in the coating, so that the generated electrostatic charge is timely led out, and the film material is endowed with excellent antistatic property.

The invention discloses a strong-hydrophobicity chromatographic stationary phase modified by a covalent triazine skeleton containing an octyl chain as well as a preparation method and application of the strong-hydrophobicity chromatographic stationary phase. Activated silica gel is modified by utilizing a silane coupling agent, so that gamma-glycidyl ether oxypropyl trimethoxy is introduced into the surface of the silica gel; and performing in-situ growth of a covalent triazine skeleton layer containing an octyl chain through a Schiff base condensation reaction to prepare the strong-hydrophobicity chromatographic stationary phase. A covalent triazine skeleton containing a hydrophobic octyl chain in the structure is used for modifying the surface of silica gel, and a bonding phase contains a triazine ring, a benzene ring, an octyl chain and an amino group. According to the stationary phase, a hydrophobic long octyl chain is introduced into a bonding unit of CTF, so that the structure, morphology and performance of the CTF are changed, a'flower-on-sphere 'morphology is formed, and the stationary phase has a rigid porous structure, adjustable hydrophilicity / hydrophobicity, a rich pi electron system, strong hydrophobicity and good separation selectivity for non-polar compounds, and can be widely applied to separation of various samples.

The invention relates to the technical field of immobilized lipase, in particular to immobilized lipase taking modified nano SiO2 as a carrier as well as a preparation method and application of the immobilized lipase. The immobilized lipase sold in the market is high in price and poor in mechanical strength, the enzyme loss is too large due to shear force or carrier structure damage in the continuous production process, and the transesterification efficiency is poor. In order to solve the technical problems, the invention provides the immobilized lipase taking the modified nano SiO2 as the carrier, the immobilized lipase is obtained by sequentially grafting a modified nano silicon dioxide carrier with an amino silane coupling agent and an epoxy silane coupling agent and loading lipase on the surface of the modified nano silicon dioxide carrier, according to the method, the immobilized lipase forms an enzyme column in a chromatographic column and then serves as a reactor, damage of mechanical stirring to lipase particles is avoided, the ester exchange degree is more effectively controlled by adjusting the flow speed of a substrate, the production cost of an enterprise can be remarkably reduced, and the product quality is improved.

The invention discloses a distillation purification method for preparing a silane coupling agent, and belongs to the technical field of preparation of silane coupling agents. The distillation and purification method for preparing the silane coupling agent comprises the following steps: step 1, mixing a silane coupling agent crude product, tetrahydrofuran, an organic antioxidant and an auxiliary agent, heating, mixing and stirring to obtain a mixture; 2, adding the mixture into a distillation tower, heating and distilling, controlling the heating temperature and the distillation rate, and ensuring stable and continuous evaporation and condensation of the silane coupling agent; and 3, collecting the condensed liquid into a collector, separating the liquid, filtering, and drying to obtain the silane coupling agent. According to the method, the product purity and yield of the silane coupling agent can be effectively improved.

The invention provides a novel metal organic framework material reinforced carbon dioxide trapping solvent and a preparation method thereof, and relates to the field of gas adsorbents. Comprising the following steps: S1, dissolving nickel salt, cobalt salt and zinc salt in water to obtain a metal salt solution; s2, uniformly mixing 2, 5-dihydroxyterephthalic acid and N, N-dimethylformamide, then adding 1-methylimidazole and ethanol, and uniformly mixing to obtain a ligand solution; s3, mixing the metal salt solution with the ligand solution, adding the mixture into a microwave reactor for reaction, filtering and drying to obtain an organic framework material; and S4, dispersing the organic framework material in deionized water, then adding an organic amine aqueous solution and a silane coupling agent, uniformly stirring, then adding an imidazolium ionic liquid, and carrying out ultrasonic oscillation to obtain the composite material. The carbon dioxide trapping solvent takes a metal organic framework material as a carrier, and the metal organic framework material is functionally modified and is matched with imidazole ionic liquid, so that the adsorption efficiency and the stability of the trapping solvent can be improved.

The invention belongs to the technical field of composite pipes, and relates to a polytetrafluoroethylene and soluble polytetrafluoroethylene composite pipe as well as a processing method and application thereof. The preparation method comprises the following steps: firstly, carrying out ring opening polymerization on D3F and blocking by using an amino-containing silane coupling agent to prepare amino-terminated fluorosilicone oil, and taking the amino-terminated fluorosilicone oil as a lubricating agent for compounding and processing PTFE and PFA. The amino-terminated fluorosilicone oil contains a CF3 chain segment which has excellent compatibility with PTFE or PFA, and meanwhile, the cross-linking agent is added to form a chemical bond and a cross-linked structure with amino at the tail end of the lubricant, so that the wear resistance, tensile strength, permeability resistance and high-temperature creep resistance of the PTFE and PFA composite pipe can be improved, and the PTFE and PFA composite pipe can adapt to a long-term high-temperature working environment.

The invention relates to the field of biological medicine preparation, and provides a semi-synthesis preparation method of semeglutide and a preparation method of a semeglutide side chain, the semi-synthesis preparation method comprises the following steps: 1, in the presence of a first base catalyst, mixing a compound SMG-1 solution with a compound III solution, reacting to obtain a compound IV, and filtering to obtain a compound III; wherein the addition amount of the first base catalyst is such that the pH value of the SMG-1 solution is 11.2-11.6; 2, in the presence of a coupling agent and a second base catalyst, a compound IV solution and a compound SMG-3 solution are mixed and coupled to obtain a compound V, and the pH value in the step 2 is 9.5-10.0; and 3, carrying out deprotection on the compound V by using a deprotection agent to finally obtain the semeglutide. The method provided by the invention has the advantages of few reaction steps, reduced cost, high semeglutide purity and high yield, and is suitable for large-scale industrial production.

The invention discloses a preparation method of Fe3O4 magnetic nanoparticles rich in carboxyl groups on the surface, which comprises the following steps: modifying Fe3O4 nanoparticles by using polyethylene glycol and silicon dioxide to enhance the dispersity and biocompatibility of the magnetic nanoparticles, modifying the surfaces of PEG-Fe3O4 coated SiO2 nanoparticles by using a silane coupling agent containing silane groups and unsaturated double bonds to obtain the magnetic nanoparticles rich in carboxyl groups on the surface, and modifying the magnetic nanoparticles rich in carboxyl groups on the surface by using a silane coupling agent containing silane groups and unsaturated double bonds to obtain the magnetic nanoparticles rich in carboxyl groups on the surface. Then octavinyl-POSS and double bonds on the surfaces of the nano particles are subjected to click modification to form an octahedral cage, 4-mercaptobenzoic acid and double bonds are further subjected to click modification, the surfaces of the nano particles are rich in carboxyl, and a polymer brush rich in carboxyl is constructed. Compared with a conventional streptavidin coupling method, a high-density polymer chain provides a large number of carboxyl active binding sites, so that the streptavidin coupling amount is increased, the antibody coupling rate is increased, and a solution is provided for applications such as high-sensitivity biological detection, efficient targeted drug delivery and stable immunoassay.

The invention belongs to the technical field of flame retardants, and relates to a high-strength hyperbranched halogen-free flame retardant as well as a preparation method and application thereof, the preparation method comprises the following steps: preparing a modified isocyanate silane coupling agent from bis (3-aminophenyl) phenylphosphine oxide and 3-isocyanatopropyltriethoxysilane; the preparation method comprises the following steps: preparing a modified amino silane coupling agent from triglyceride isocyanurate and 3-aminopropyltriethoxysilane; the high-strength hyperbranched halogen-free flame retardant is prepared from a modified isocyanate silane coupling agent and a modified amino silane coupling agent. The silane coupling agent is modified according to the principle that an isocyanate group on the surface of the silane coupling agent can chemically react with a tertiary amine group and an epoxy group can react with an amino group, the two modified silane coupling agents form the hyperbranched flame retardant after being hydrolyzed, the highly branched structure enables the intermolecular force to be small, and the hyperbranched flame retardant has the advantages of high flame retardance and high flame retardancy. And the flame retardant shows excellent mechanical strength and excellent flame retardant effect.