925 results about "Schiff base" patented technology

The invention relates to the technical field of food fresh-keeping materials, in particular to a chitosan-curcumin nano-composite fresh-keeping agent and a preparation method thereof.The chitosan-curcumin nano-composite fresh-keeping agent comprises nano-particles of a chitosan-sodium alginate-oxidized sodium alginate interpenetrating network structure, according to the nanoparticles, protonated amino groups of chitosan and carboxyl groups of sodium alginate form a polyelectrolyte compound core, aldehyde groups of oxidized sodium alginate and amino groups of chitosan are subjected to a Schiff base reaction to form a chemical cross-linked network, and zinc ions, amino groups of chitosan, carboxyl groups of sodium alginate and carboxyl groups of oxidized sodium alginate form coordination cross-linking; curcumin and epigallocatechin gallate form a compound through a hydrogen bond and a hydrophobic effect, the compound is embedded in an interpenetrating network structure, beta-diketone groups of curcumin and zinc ions form chelating coordination, a chitosan-sodium alginate-oxidized sodium alginate ternary interpenetrating network is constructed, and the chitosan-sodium alginate-oxidized sodium alginate ternary interpenetrating network structure is formed. The stability is improved by utilizing the synergistic effect of triple mechanisms of electrostatic interaction, Schiff base chemical bonds and zinc ion coordination.

The invention discloses a copper surface micro-etching coarsening solution for a fine circuit as well as a preparation method and application of the copper surface micro-etching coarsening solution, and relates to the technical field of printed circuit board manufacturing. The copper surface micro-etching coarsening solution for the fine circuit is prepared from, by mass concentration, 60 g / L to 100 g / L of sulfuric acid, 40 g / L to 60 g / L of hydrogen peroxide, 0.5 g / L to 2 g / L of zinc sulfate, 10 g / L to 30 g / L of copper ions, 0.5 g / L to 1 g / L of pyridine heterocycle-containing Schiff base, 10 g / L to 100 g / L of ethyl alcohol, 1 g / L to 3 g / L of 2-mercaptobenzothiazole, 1 g / L to 5 g / L of methionine and 1 g / L to 5 g / L of polyacrylamide. According to the copper surface micro-etching coarsening solution, the 2-mercaptobenzothiazole and the methionine in the copper surface micro-etching coarsening solution can enable the copper surface to form a honeycomb structure under the low micro-etching amount, the zinc sulfate and the pyridine heterocyclic ring-containing Schiff base can form a composite film layer with copper ions on the surface of the honeycomb structure, and the interlayer binding force is improved.

The invention discloses a high-oxidation-resistance long-life polyethylene cable sheath material and a preparation method thereof, and relates to the technical field of high polymer materials. Comprising the following components: high-molecular-weight high-density polyethylene, surface-modified nano-dioxide, furan-maleimide grafted polyethylene, a Schiff base dynamic cross-linking agent, tea polyphenol grafted polyethylene, a temperature-responsive oxygen-blocking microcapsule, a main antioxidant, an auxiliary antioxidant, an emergency antioxidant, a light stabilizer, a halogen-free flame retardant, a processing aid and an acid absorbent. According to the invention, the main antioxidant, the auxiliary antioxidant and the tea polyphenol grafted polyethylene form a chemically synthesized and naturally modified composite antioxidant system, the designed service life of the material is greatly prolonged, the temperature-responsive oxygen-blocking microcapsule automatically cracks to release the core material when the operating temperature of the cable is greater than or equal to 90 DEG C, a dynamic oxygen-blocking layer is formed, and the service life of the cable is prolonged. The defect that the effect of traditional physical oxygen barrier is attenuated at high temperature is overcome, and the oxygen permeability at high temperature is reduced compared with that of a single nano barrier scheme.

The invention relates to the technical field of adsorption materials, and discloses a post-modified imine-COF adsorbent and a preparation method and application thereof, the adsorbent comprises the following structural units: a COF skeleton, which is a two-dimensional or three-dimensional porous skeleton formed by an aromatic aldehyde monomer and an amino monomer through a Schiff base reaction; the imine group is formed in a COF skeleton through a post-modification reaction, and the imine group is-C = NR, r is selected from one or more of a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted heterocyclic group and a hydrogen atom. The adsorbent retains excellent structural characteristics of the COF material, realizes high density and uniform distribution of functional groups, and avoids interference of functional monomers on crystal nucleation and growth, so that the adsorption performance of the adsorbent is improved, and the adsorbent can efficiently capture rare earth when being applied to a rare earth-containing solution.

The invention belongs to the field of analytical chemistry, relates to material preparation, and particularly discloses a preparation method of a copper-doped covalent organic framework and application of the copper-doped covalent organic framework in adrenaline colorimetric detection. Firstly, 1H-indazole-4, 7-diamine (Iz) and 1, 3, 5-triformyl phloroglucinol (Tp) are used as monomers to synthesize a novel covalent organic framework (Iz-Tp COF) through a Schiff base reaction, copper ions are introduced into the Iz-Tp COF framework to prepare a novel metal covalent organic framework (Iz-Tp (at) Cu), and then according to the phenomenon that the Iz-Tp (at) Cu can catalyze oxidation color development of epinephrine, the metal covalent organic framework (Iz-Tp (at) Cu can catalyze oxidation color development of epinephrine. According to the present invention, the simple, sensitive and efficient adrenaline colorimetric detection method is established, the test conditions are finally optimized, the standard addition method is combined to accurately determine the adrenaline concentration in the urine, and the good practical application value is provided.

The invention belongs to the field of photocatalytic preparation of hydrogen peroxide, and relates to a novel secondary amine linked covalent organic framework material (AR-COF) as well as a preparation method and application thereof. According to the material, tetraaldehyde phenyl porphyrin and 2, 5-diamino-1, 4-benzenediol dihydrochloride are subjected to a Schiff base reaction to synthesize an imine bond connected porphyrinyl covalent organic framework (IM-COF), and then synthesis post-modification (PSM) is performed on the imine bond connected porphyrinyl covalent organic framework (IM-COF) so that the imine bond connected porphyrinyl covalent organic framework (IM-COF) and sodium borohydride can be subjected to a reduction reaction to generate AR-COF. The photocatalytic stability of the material is maintained through modification after synthesis, the catalytic activity is improved, and the original crystal structure is not damaged. A photocatalytic hydrogen peroxide production experiment shows that the catalytic activity of AR-COF under 420 nm monochromatic light is superior to that of IM-COF, the yield under an oxygen condition reaches 7.79 mmol.g <-1 >. H <-1 >, and hydrogen peroxide can be stably produced. The method utilizes solar energy for green synthesis under mild conditions, and provides a safe and efficient method for hydrogen peroxide production.

The invention relates to absorbable adhesive styptic powder and a preparation method thereof, and the absorbable adhesive styptic powder is characterized in that the absorbable adhesive styptic powder is formed by cross-linking aldehyde polysaccharide and a polyamino compound through Schiff base reaction, the raw materials are selected from at least one of glucan, sodium carboxymethyl cellulose, sodium hyaluronate, chitosan and carboxymethyl starch; the polyamino compound is selected from at least one of polylysine, polypeptide, bovine serum albumin and polyamine; the styptic powder is porous particles with the particle size of 10-1000 meshes, is cured into gel within 10 seconds after being in contact with body fluid, and is completely degraded within 15-60 days. According to the scheme, the styptic powder has the advantages of rapid wet adhesion, controllable degradation and excellent processability, and is an urgent clinical demand.

This invention discloses a method for preparing a pH / glucose dual-responsive chronic wound dressing containing frankincense essential oil, comprising: (1) using 4-formaldehyde phenylboronic acid as a crosslinking agent to form Schiff base and borate ester bonds with carboxymethyl chitosan and two different molecular weight hyaluronic acids, respectively, to prepare a hydrogel capable of filling skin surface wounds and performing dual dynamic covalent crosslinking adhesion, and freeze-drying for later use; (2) preparing frankincense essential oil into microcapsules by emulsification coagulation method, and freeze-drying for later use; (3) mixing the hydrogel with the freeze-dried powder of frankincense essential oil microcapsules, adding deionized water or PBS and stirring to reconstitute to form a pH / glucose dual-responsive hybrid hydrogel dressing coated with frankincense essential oil microcapsules. The composite dressing prepared by this invention has anti-inflammatory, antioxidant, antibacterial, and healing-promoting effects, is quick and easy to prepare, and has the ability to respond to the acidic / high-glucose microenvironment of diabetic wounds, and has important practical application value.

The invention discloses a precise construction strategy of a dibenzothiophene sulfuryl covalent organic framework material and systematically explains efficient application of the dibenzothiophene sulfuryl covalent organic framework material in photocatalytic synthesis of thiadiazole and derivatives thereof. The achievement relates to a plurality of leading subjects such as catalytic chemistry, organic synthesis, material science, environmental engineering and green chemistry. According to the method, 2, 4, 6-triformyl phloroglucinol and 3, 7-diaminodibenzo [b, d] thiophene-5, 5-dioxide are taken as construction units, and the crystalline S-COF rich in sulfuryl active sites can be quantitatively obtained through topology-oriented Schiff base condensation under the conditions of protonic acid catalysis, no water and no oxygen. Under the radiation condition of visible blue light, S-COF is used as a heterogeneous photocatalyst to drive green synthesis of 3, 5-di-p-tolyl-1, 2, 4-thiadiazole and series of derivatives thereof; the invention provides a new catalyst design normal form for light-induced organic conversion, and lays a solid foundation for sustainable development-oriented efficient synthesis chemistry.

The invention relates to the technical field of sewage treatment, in particular to a preparation method of a degradable bactericide for an oil field. According to the invention, a hydroxypropyl guanidine gum-polycaprolactone-ethylenediamine fragment copolymer is taken as a carrier, a methylisothiazolinone quaternary ammonium salt (Q-MIT) bactericide is loaded, and the degradable bactericide for the oil field is obtained by cooperating with a dodecyl ethyl sulfide (TC-SE) bactericide and combining with sodium polyaspartate. A carrier forms a hydrogen bond with a polar group on the surface of a biological membrane through a hydroxypropyl guanidine gum main chain to realize targeted anchoring, a polycaprolactone branched chain encapsulates Q-MIT through a hydrophobic effect, primary amino groups of ethylenediamine are introduced to form a pH sensitive Schiff base bond with Q-MIT, and the primary amino groups and adipic dihydrazide form a thermal response hydrazide bond to construct a dual dynamic covalent bond, so that controlled release of Q-MIT is realized, and the biomembrane is prepared. And moreover, the components of the whole system are connected through degradable chemical bonds, so that the environmental protection property and sustainability of oil field operation are guaranteed.

The present application belongs to the technical field of flame-retardant materials, and specifically relates to a halogen-free flame retardant containing a Schiff base structure, a preparation method thereof, and application of the halogen-free flame retardant in epoxy resin. The halogen-free flame retardant containing phosphorus, nitrogen elements and a Schiff base structure is obtained through a Schiff base reaction between an intermediate and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, wherein the intermediate is prepared through a nucleophilic substitution reaction between an aldehyde group-containing phenolic compound and an acyl chloride compound. The flame retardant has good thermal stability, significantly improved char yield, excellent flame-retardant effect, and significantly improved mechanical properties due to the combination of the Schiff base structure and phosphorus and silicon elements. The halogen-free flame retardant is further used to modify epoxy resin to prepare a flame-retardant epoxy resin, which can significantly improve the char performance and mechanical properties of the epoxy resin with little influence on the thermal performance of the epoxy resin cured product, and has excellent flame-retardant efficiency.

The invention discloses a preparation method of a low-chlorine composite environment-friendly coal transportation anti-freezing agent, and belongs to the technical field of anti-freezing solutions. The anti-freezing solution is used for solving the technical problems of complex components and poor anti-freezing and metal corrosion resistance of the anti-freezing solution for coal transportation in the prior art. The preparation method of the low-chlorine composite environment-friendly coal transportation anti-freezing agent comprises the following step: uniformly mixing the compound pour point depressant, the modified corrosion inhibitor, the thickening stabilizer and the industrial water to prepare the low-chlorine composite environment-friendly coal transportation anti-freezing agent. The compound pour point depressant comprises an organic pour point depressant and an inorganic pour point depressant; the organic pour point depressant is obtained by reacting unsaturated azole, sodium methallyl sulfonate and fumaric acid; the unsaturated nitrogen is obtained by reaction of an intermediate B and benzaldehyde, and the intermediate B is obtained by reaction of triazole and ethyl chloroacetate; the modified corrosion inhibitor is obtained by carrying out a reaction on potassium thiocyanate, benzoyl chloride and chitosan vanillin Schiff base. The anti-freezing solution prepared by the invention has the advantages of moderate fluidity, good metal corrosion resistance and good anti-freezing performance.

The invention belongs to the field of flame-retardant composite materials, and particularly relates to a multifunctional flame retardant and application thereof in epoxy resin. The method comprises the following steps: firstly, carrying out nucleophilic substitution reaction on tert-butyldimethylsilyl chloride and syringaldehyde to obtain a primary intermediate product; carrying out condensation reaction on the primary intermediate product and an amino-containing compound to form a secondary intermediate product with a Schiff base structure; and finally, carrying out addition reaction on the secondary intermediate product and a specific phosphorus-containing reagent to successfully prepare the target flame retardant. Researches show that the flame retardant is remarkable in efficiency, can effectively improve the limit oxygen index (LOI value) and the vertical combustion test (such as UL-94) grade of a material after being applied to an epoxy resin system, and endows the composite material with excellent light transmission, anti-dripping performance and good ultraviolet shielding characteristic.

The invention discloses a hydrogel-based helicobacter pylori killing medicine and a preparation method thereof in the technical field of biomedical materials, and the hydrogel medicine adopts a shell-core layered structure and comprises an outer layer and an inner layer; the outer layer is a high-density cross-linked polyethylene glycol diacrylate network, and cellulose nanocrystals modified by silane are dispersed in the polyethylene glycol diacrylate network; pH-sensitive Schiff base bonds and / or boric acid ester bonds are embedded in the inner layer, and an antibacterial agent is loaded on the inner layer. Structural expansion and breaking of the hydrogel are controlled through a multi-layer structure, multiple loaded antibacterial agents are released according to pH response, the influence of drug resistance is avoided through sterilization of multiple mechanisms, the preparation process and device of the hydrogel drug are integrated, the production cost is reduced, and the clinical conversion efficiency is guaranteed.

The invention relates to the technical field of sodium batteries, and discloses a preparation method of a sodium-ion battery diaphragm, the sodium-ion battery diaphragm and application, the preparation method comprises the following steps: dissolving triaminoguanidine hydrochloride in 1, 4-dioxane, and carrying out condensation reaction with hydrazine hydrate to generate triaminoguanidine chloride; performing Schiff base condensation reaction on the triaminoguanidine chloride and 2, 5-dihydroxy terephthalaldehyde to obtain a chlorine-containing covalent organic framework, and performing ion exchange on the chlorine-containing covalent organic framework to generate a fluorine-containing covalent organic framework; mixing raw materials containing the fluorine-containing covalent organic framework, polyvinylidene fluoride and N-methyl pyrrolidone, uniformly coating two sides of polypropylene with the mixture, and performing vacuum drying to obtain the sodium-ion battery diaphragm. According to the technical scheme provided by the invention, the diaphragm material capable of uniformly adjusting sodium ion transmission, reducing a desolvation potential barrier and promoting formation of a stable SEI layer can be obtained.

The invention discloses a preparation method and application of a metal covalent organic framework material, and the prepared metal covalent organic framework material can be used for adsorption separation of elemental iodine pollutants and shows excellent iodine adsorption capacity and rate. According to the preparation method, 1H-pyrazole-4-formaldehyde and copper nitrate trihydrate are subjected to a solvothermal reaction to prepare a copper ion ring trinuclear metal complex with an aldehyde group, and the copper ion ring trinuclear metal complex and 1, 3, 5-tri (4-aminophenyl) benzene are further subjected to a Schiff base reaction to prepare the metal covalent organic framework material containing copper ions. According to the metal covalent organic framework material disclosed by the invention, copper ion active adsorption sites in a chemical structure are also retained while a developed microporous structure is maintained, and the interaction strength of pore channels to iodine is remarkably enhanced, so that the iodine adsorption rate and capacity are remarkably improved. The preparation method is simple, convenient, universal and high in controllability, and large-scale production and manufacturing of the metal covalent organic framework adsorption material can be achieved.

The invention belongs to the technical field of artificial veneers, and particularly relates to a fragrance-releasing blue-light-resistant microcapsule and a preparation method thereof, impregnated bond paper of the fragrance-releasing blue-light-resistant microcapsule, a fragrance-releasing blue-light-resistant ecological board and a preparation method of the fragrance-releasing blue-light-resistant ecological board. The technology aims at solving the problems of indoor blue light harm and air quality, and the problems that in the prior art, stable coexistence of a fragrance releasing component and an anti-blue-light component is difficult, and the technology is not compatible. The core is to prepare a multifunctional microcapsule through a unique interfacial polymerization and Schiff base in-situ reaction synchronous process: compound plant essential oil is taken as a core material, a vanillin-polyethyleneimine Schiff base conjugated structure is generated in situ in a wall material, and nanoparticles are cross-linked and fixed, so that a polyurethane / polyurea wall material is formed. The microcapsule is added into an adhesive layer of impregnated bond paper, and then is compounded with a base material through hot pressing to prepare the ecological board. The fragrance releasing and blue light resisting functions are successfully integrated on the board body, the effects that the blue light absorptivity at the wave band of 400-450 nm is larger than or equal to 70%, the formaldehyde release amount is smaller than or equal to 0.025 mg / m, and the fragrance is lasting are achieved, and the technology is highly compatible with an existing production line.

The invention relates to the technical field of corrosion inhibitors for oil wells, in particular to a multipurpose high-temperature acidizing corrosion inhibitor for an oil field and a preparation method thereof, and the multipurpose high-temperature acidizing corrosion inhibitor for the oil field is obtained according to the following method: adding a required amount of N 'N-dimethylformamide, butynediol and an emulsifier into self-made bis-schiff base quaternary ammonium salt, fully stirring, then adding benzotriazole, and stirring to obtain the multipurpose high-temperature acidizing corrosion inhibitor. According to the invention, the self-made bis-Schiff base quaternary ammonium salt can form a compact and firm adsorption film on a metal matrix, so that contact between an acid solution and metal is reduced, and effective protection is realized; the raw materials are also compounded with other small molecular compounds of N 'N-dimethylformamide, butynediol emulsifier and benzotriazole, so that the multipurpose high-temperature acidizing corrosion inhibitor for the oil field has the characteristics of strong adaptability, good temperature resistance and good corrosion inhibition effect aiming at different acid liquor types.

The invention relates to the technical field of detection kits, in particular to a blood coagulation reaction linked lupus anticoagulant fluorescence detection kit and application thereof, the kit contains a screening-confirmation integrated reagent, a calibration product, a quality control product and an anticoagulation interference inhibitor; the integrated reagent is divided into a reagent A and a reagent B, the reagent A contains a buffer solution, recombinant snake venom thrombin, composite phospholipid, a fluorescent substrate and other components, and the reagent B contains prothrombin, calcium ions, high-concentration composite phospholipid and other components; the composite phospholipid system is formed according to a specific proportion and modifies beta2-glycoprotein I, the fluorescence enhancement-stabilization system is formed by matching a Schiff base compound with a stabilizer, the calibrator is a series of lupus anticoagulant standard substances, and the quality control substance comprises simulants with different concentrations and negative control. The anti-interference capability is high, and the influence of anti-coagulant drugs and enzyme source fluctuation is reduced; the signal amplification effect is obvious, the detection sensitivity is high and the reagent stability is good; the operation is simple and convenient, screening and confirmation are integrally completed, and a conventional fluorescence detector is adapted.

The invention relates to the technical field of polyester fibers, in particular to a preparation method of antibacterial modified polyester fibers, the prepared antibacterial modified polyester fibers have excellent antibacterial performance, a multi-layer antibacterial system is formed by introducing a nano-zinc oxide and Schiff base compound antibacterial agent into the polyester fibers, and the antibacterial performance of the polyester fibers is improved. Nano zinc oxide and copper / zinc oxide particles have broad-spectrum antibacterial property and can destroy cell walls and cell membranes of bacteria so as to achieve the antibacterial effect, and Schiff base as an organic antibacterial agent can be combined with receptors on the cell membranes of the bacteria to enhance the antibacterial effect; chitosan and cinnamyl aldehyde are adopted as raw materials for preparation of the Schiff base, and the two substances have good biocompatibility and degradability, so that the Schiff base compound antibacterial agent is safer and more environmentally friendly in the fiber; the nano zinc oxide, the copper / zinc oxide particles, the chitosan, the cinnamyl aldehyde and the like in the raw materials are all environment-friendly materials and are good in degradability, and environmental pollution and ecological damage can be reduced.

The invention relates to the field of biomedical materials, and particularly provides injectable adhesive carboxylated chitosan / dialdehyde starch hemostatic hydrogel and application thereof.The hemostatic hydrogel is formed by carboxylated chitosan sol and dialdehyde starch size through Schiff base reaction, hydrogen bond construction and in-situ rapid crosslinking by means of a bidirectional pumping and injecting delivery strategy, and the hemostatic hydrogel is prepared through a two-way pumping and injecting delivery strategy, and the injectable adhesive carboxylated chitosan / dialdehyde starch hemostatic hydrogel is prepared from the carboxylated chitosan sol, the dialdehyde starch size and the injectable adhesive carboxylated chitosan / dialdehyde starch hemostatic hydrogel. The hydrogel has the advantages of good biocompatibility, injectability, adhesion, personalized adaptation and the like, integrates multiple hemostasis mechanisms, a physical barrier effect of rapid gelation, an expansion compression effect of water absorption swelling, an electrical neutralization effect of carboxylated chitosan amino and a tissue adhesion effect of dialdehyde starch aldehyde group, realizes multi-scene rapid and efficient hemostasis, and has a wide application prospect. The preparation method of the injectable adhesive hemostatic hydrogel is low in cost, innovative in technology, mild in condition, convenient to store and beneficial to large-scale batch production, and has a wide application prospect in the field of efficient hemostatic hydrogel.

The invention discloses modified cellulose nanofiber reinforced bi-crosslinking immunoregulation hydrogel as well as a preparation method and application thereof, and belongs to the technical field of biological materials and biomedical engineering. Oxidized sodium alginate and dopamine grafted gelatin are adopted to prepare a main body of the composite hydrogel, aldehyde groups on the oxidized sodium alginate and amino groups on the gelatin can form Schiff base bonds, and borax, the oxidized sodium alginate and vicinal diol structures on modified cellulose nanofibers can form boric acid ester bonds. The double-crosslinking structure enhances the mechanical property of the hydrogel. The borate bond and the Schiff base bond are both dynamic chemical bonds and can respond to pH change, so that the hydrogel is endowed with self-healing performance and pH-responsive drug release ability, the hydrogel can quickly release liposome with an anti-inflammatory function in an acidic inflammatory environment in the early stage of cartilage injury, and the hydrogel recovers to an original state after fracture caused by joint movement. And the overall stability of the hydrogel is ensured by the double-crosslinking structure.

The invention discloses a preparation method and application of collagen derivative and polysaccharide substance compounded self-gel hemostatic powder, and relates to the field of biomedical materials. Aminated collagen derivatives and aldehyde polysaccharide substances are subjected to a Schiff base reaction through amino groups and aldehyde groups; further obtaining the Schiff base cross-linked aminated collagen derivative-aldehyde polysaccharide hydrogel, freeze-drying, and grinding into powder, so as to obtain the self-gel hemostatic powder. The self-gel hemostatic powder disclosed by the invention forms hydrogel in a wound tissue for adhesion and sealing, so that rapid hemostasis is realized, postoperative adhesion at the wound tissue is avoided, and healing of a wound is facilitated; after hemostasis is completed, the self-gel powder can be dissociated and removed from the tissue surface, and the risk that thrombus is formed and immunological rejection is caused is reduced; after hemostasis is completed, the hemostasis powder can be metabolized and absorbed by a human body along with thrombus, so that the residue of the hemostasis powder in the body is reduced, and the safety is improved.

The invention relates to the technical field of flame-retardant materials, and particularly discloses a full-bio-based reactive flame retardant, a zero-VOC bio-based basic flame-retardant waterborne polyurethane emulsion and a preparation method of the zero-VOC bio-based basic flame-retardant waterborne polyurethane emulsion. According to the invention, vanillin, lysine and phytic acid are taken as raw materials, a full-bio-based reactive flame retardant is synthesized, and the full-bio-based reactive flame retardant can form chemical bonding with a waterborne polyurethane matrix, so that intrinsic flame retardance is realized. A molecular structure of the cosolvent contains a plurality of high-activity groups such as hydroxyl groups, the cosolvent has excellent thermal stability and lasting flame-retardant efficiency, can be chemically bonded with a waterborne polyurethane matrix under a low-temperature condition, remarkably reduces the dosage of the cosolvent, and can realize zero VOC solvent emission when being applied to a chemical flame-retardant modification process of waterborne polyurethane. Meanwhile, the Schiff base group contained in the flame retardant endows the flame retardant with an extra antibacterial function, breeding of microorganisms on the surface and inside of the material can be inhibited after the flame retardant is combined with waterborne polyurethane, material degradation caused by microbial erosion is avoided, the service life of the material is prolonged, and the using effect of the material is improved.

The present application relates to a kind of pH / H2O2 dual-response drug-loaded hydrogel and its preparation method and application, by ε-polylysine derivative as antitumor active ingredient, with oxidized dextran through Schiff base reaction crosslinking rapid gelation. While using 2-formylphenyl boronic acid covalently package CD73 small molecule inhibitor APCP. ε-polylysine derivative has oncolytic activity, can induce ICD and promote the infiltration of immune cells in tumor cells. CD73 small molecule inhibitor APCP can block extracellular CD39-CD73-adenosine pathway, reduce the level of immunosuppressive metabolite adenosine in tumor tissue, so as to activate the infiltrated immune cells, restore its anti-tumor function. The hydrogel of ε-polylysine derivative and APCP co-delivery synergistically inhibits the effect of tumor growth, and its curative effect is greater than the treatment effect of single drug, and is superior to positive control drug oxaliplatin (OXA). The pH / H2O2 dual-response hydrogel is rapidly gelled, and has good biological safety under mild reaction conditions.

The invention relates to the technical field of papermaking and food packaging materials, in particular to a preparation method of full-degradable plastic-substituted high-strength food packaging paper. Preparing a fiber layer by taking plant fiber as a base material; the preparation method comprises the following steps: grafting a methyl methacrylate-butyl acrylate block copolymer on nano-cellulose through an atom transfer radical polymerization technology to prepare enhanced nano-cellulose; dialdehyde starch rich in aldehyde groups and chitosan are subjected to a Schiff base reaction to form a dynamic cross-linked network, polylactic acid microspheres modified by beta-cyclodextrin are introduced to serve as supramolecular enhancement units, and functional coating liquid is prepared; and finally, coating the functional coating liquid on the fiber layer, and drying, cross-linking and curing to obtain a finished product. Through cooperation of chemical grafting, dynamic covalent bonds and supramolecular action, the packaging paper is endowed with extremely high strength and toughness and excellent oil and moisture resistance and heat sealability, meanwhile, it is ensured that the packaging paper can be completely biodegraded in the natural environment, and functional replacement of traditional plastic packaging is successfully achieved.

The invention belongs to the technical field of preparation of composite fibers, and particularly relates to a preparation method of a heterocycle-containing polyamide composite fiber, which comprises the following steps: under the protection of inert gas, mixing a heterocycle-containing diamine monomer and terephthaloyl chloride in a polar solvent in proportion to prepare heterocycle-containing polyamide; mixing the amino modified cellulose nanomaterial, a tannic acid modified metal oxide and a Schiff base oligomer to form a composite dispersion liquid, adding heterocycle-containing polyamide, a lithium salt and a cross-linking agent into the composite dispersion liquid, dissolving and defoaming to obtain a spinning solution, and extruding the spinning solution into a coagulating bath through wet spinning; and carrying out multi-step washing, drying and heat setting treatment to obtain the heterocycle-containing polyamide composite fiber.

The present application relates to a kind of shiff base metal complex liquid desulfurizer and its preparation method and use, by amine and aldehyde condensation preparation the structure in the shiff base ligand containing C=N double bond, the lone pair electron of nitrogen atom on shiff base and metal atom are mutually cooperated to form shiff base metal complex, under the condition of oxygen or air as activating agent, the catalyst can be oxidized into inorganic sulfur with organic sulfur.The shiff base metal complex liquid desulfurizer of the present application is synthesized by low-cost raw material, without adding desulfurizer in the desulfurization process, solve the problems such as large amount of existing desulfurizer, need to be added continuously.At the same time, the desulfurizer is liquid desulfurizer, increase the contact area with organic sulfur gas, improve the desulfurization efficiency, the desulfurization rate of methyl mercaptan is higher than 99%.

The invention discloses a nitrogen-phosphorus intumescent flame retardant based on a hypophosphorous acid derivative and oligomerization Schiff base as well as a preparation method and application thereof, and relates to the technical field of macromolecular flame-retardant materials. The invention discloses a nitrogen-phosphorus intumescent flame retardant based on a hypophosphorous acid derivative and oligomeric Schiff base. The nitrogen-phosphorus intumescent flame retardant has a structure as shown in a general formula (I), wherein the Schiff base chain segment is an oligomerization Schiff base chain segment formed by condensation of aromatic polyamine and aromatic polyaldehyde and has a linear or hyperbranched structure, m, n and x are positive integers larger than 0, m + n is larger than or equal to 2 and smaller than or equal to 8, and x is larger than or equal to 2 and smaller than or equal to 30. According to the flame retardant provided by the invention, an oligomer structure and an introduced benzene ring structure have good compatibility with a polymer matrix and are not easy to migrate and separate out, so that long-acting flame retardance and mechanical properties of a material can be maintained, expensive DOPO is successfully replaced by hypophosphorous acid which is low in cost and easy to obtain, and a solid foundation is laid for large-scale industrial popularization and application.

The invention discloses a preparation method and application of sodium gallate-polyphenol chitosan antibacterial hydrogel, firstly, gallic acid and sodium acetate are used as raw materials, a high-purity sodium gallate complex 5-carboxyl-2, 3-sodium dihydroxyphenolate is prepared at normal temperature and normal pressure, then a polyphenol compound and chitosan are cross-linked through Schiff base reaction, and the sodium gallate-polyphenol chitosan antibacterial hydrogel is obtained. And finally, carrying out rotary evaporation treatment, so that the sodium gallate is loaded in the polyphenol chitosan hydrogel system to obtain the antibacterial hydrogel. Sodium gallate is used as a functional component, uniform loading of sodium gallate in a polyphenol chitosan hydrogel system is realized through dual effects of physical adsorption and chemical bonding, the loading mechanism can effectively avoid aggregation and burst release of sodium gallate, stable release of antibacterial components is ensured, and the antibacterial property of the hydrogel is improved. The slow release time of the antibacterial hydrogel under the conditions that the pH values are 5.5 and 7.2 respectively exceeds 24 hours; and the antibacterial hydrogel has an inhibition effect on both gram-positive bacteria and gram-negative bacteria.