333 results about "Catechol" patented technology

The application relates to a dry powder drag reducer for fracturing fluid and a preparation method thereof, and belongs to the technical field of drag reducers; the dry powder drag reducer is copolymerized and modified by preparing a polymerizable modifier, aromatic rings and sulfonic acid ion structures are introduced into the dry powder drag reducer, the high-temperature resistance and salt resistance of the dry powder drag reducer are effectively improved, in addition, the modified dry powder drag reducer structure also has a catechol structure, can form a stable five-membered ring borate with a boron crosslinking agent, and the dry powder drag reducer can be mixed with a guar gum drag reducer when the boron drag reducer is used, so that the problem of poor sand carrying capacity of the dry powder drag reducer is effectively solved.

The invention discloses a catechol side group-containing polylysine derivative as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) dissolving catechol acid in an organic phase, firstly adding NHS, stirring and dissolving until the materials are uniformly mixed, then adding EDC.HCl, and stirring and reacting to obtain a catechol-NHS intermediate solution; (2) dissolving polylysine or a salt thereof in a water phase, and adjusting the pH value to 6.0-7.0 by using an alkaline solution to obtain a solution of polylysine or a salt thereof; and (3) adding the intermediate solution obtained in the step (1) into the polylysine or the salt solution thereof obtained in the step (2), and maintaining the pH value of the reaction system at 5.0-6.0 by using an alkaline solution to obtain the catechol side group-containing polylysine derivative. The preparation method is short in reaction time and mild in reaction condition, and the obtained product is high in grafting rate and high in raw material conversion rate and has a good application prospect in the aspects of tissue adhesives and the like.

The invention discloses a bio-based polymer emulsion as well as a preparation method and application thereof, and belongs to the technical field of aqueous polymer emulsions. The emulsion comprises an aqueous continuous phase, bio-based polymer particles, a stabilizing system, and a bionic catechol adhesion component. Specific modified starch is innovatively utilized for assistance, and a bionic adhesion shell layer is constructed on the surface of a bio-based polymer core in situ. Compared with similar products in the market that adhesion to inert substrates can be improved only by adding a large amount of tackifying components, the scheme has the advantages that excellent dry and wet adhesion can be realized on the surfaces of difficult-to-adhere substrates such as polypropylene and polyethylene only by constructing an extremely thin interface functional layer, and the functionalization efficiency and economical efficiency of the bio-based material are greatly improved. Meanwhile, the system effectively overcomes the industrial problem that the high-solid-content emulsion is easy to settle, has excellent storage stability and construction adaptability, and conforms to the development trend of sustainable barrier packaging and high-performance water-based coatings in the future.

The invention relates to the technical field of fabrics, in particular to a cool-feeling long cilia strip and a preparation method thereof.The cool-feeling long cilia strip is composed of cool-feeling fibers and a long cilia strip base material and is characterized in that the cool-feeling fibers comprise a core layer, a functional skin layer and an outer thin skin layer; the functional skin layer is prepared from the following components: a sulfonated copolyester matrix, catechol grafted master batch, surface modified zeolite nano powder, an anti-hydrolysis agent and an antioxidant, and the functional skin layer also contains introduced Zn < 2 + > and Mg < 2 + >. Zn < 2 + > and Mg < 2 + > which are stably combined on anchoring points of sulfonated copolyester are subjected to hydration endothermic reaction when being in contact with water, so that a cool feeling is generated; the surface modified zeolite nano powder synergistically enhances moisture absorption and water temporary storage by virtue of the specific surface area, and continuously provides water for an ionized hydration reaction to prolong and amplify a cool feeling effect; the catechol grafting structure endows the fiber with antibacterial performance, and long-term stability of the structure is ensured through an interface enhancement effect. And the outer layer hydrophilic polyester is matched, so that the product has comfort, durability and functionality.

The present disclosure provides a method for the chemoselective modification of a target molecule. The subject methods comprise contacting a target molecule comprising a thiol moiety with a biomolecule comprising a reactive moiety, wherein the reactive moiety is produced by reacting a biomolecule comprising a phenol moiety or catechol with an enzyme capable of oxidizing the phenol moiety or the catechol moiety. The contacting is performed under conditions sufficient to conjugate the target molecule to the biomolecule, thereby producing a modified target molecule. The present disclosure provides compositions comprising a subject target molecule comprising a thiol moiety and a biomolecule comprising a phenol moiety or a catechol moiety. The present disclosure provides kits for performing the subject methods. The disclosure also provides modified target molecules and methods of using the same.

The invention provides a diesel oil anti-wear agent and a preparation process thereof, and belongs to the technical field of diesel oil additives, and the preparation process comprises the following steps: mixing and stirring diisooctyl maleate and xylene, adding diethylenetriamine and deionized water, carrying out heating reaction, adding toluene, 4-(aminomethyl) pyridine and ethylene oxide, carrying out mixing reaction, filtering, washing, and drying to obtain the diesel oil anti-wear agent. The pyridinium-based polyester hollow capsule is prepared; the preparation method comprises the following steps: mixing xylene, catechol, ethylene phosphonic acid, ammonium persulfate and deionized water, heating, dispersing in cyclohexane, adding polyvinyl alcohol, octadecyl methacrylate and azodiisobutyronitrile, mixing and reacting to obtain catechol phosphonate nano colloidal particles; mixing and stirring the fatty acid ester solution, the oleoyl fluorocarbon copolymer and the pyridinium-based polyester hollow capsule, adding the catechol phosphonate nano colloidal particles, continuously stirring, performing ultrasonic treatment, and degassing to obtain the diesel oil anti-wear agent. The diesel oil antiwear agent can improve the antiwear property and demulsibility of the diesel oil antiwear agent.

The invention discloses a salicylic acid decarboxylase mutant and application of the salicylic acid decarboxylase mutant in degradation of salicylic acid. The mutant is obtained by carrying out site-specific modification on salicylic acid decarboxylase NahG, and specifically, valine at the 46th site, tyrosine at the 380th site and leucine at the 382nd site of an amino acid sequence shown in SEQ ID NO.2 are mutated into cysteine, phenylalanine and phenylalanine at the same time. The mutant shows remarkably improved catalytic efficiency, and salicylic acid can be efficiently and thoroughly decarboxylated and converted into catechol under mild conditions. The invention also provides a coding gene, a recombinant vector and an engineering bacterium of the mutant. The mutant not only can be used for efficient bioremediation of salicylic acid pollution, but also can effectively break through and accelerate a naphthalene catabolism pathway due to the characteristic of directionally generating catechol, and has important application value in the fields of environmental pollution abatement and biological catalysis.

This invention discloses a ternary composite adsorbent based on iron-catechol-boric acid, its preparation method, and its application, belonging to the field of dyeing and printing wastewater treatment. The adsorbent of this invention uses tannic acid with a surface rich in catechol groups as a substrate. A stable metal-phenolic network is formed through the coordination of trivalent iron with catechol groups, efficiently capturing anions using metal bridging and electrostatic attraction to form the adsorption core. Boric acid groups are further introduced as specific recognition units, forming specific dynamic covalent bonds with the catechol groups of anionic dyes. Compared with traditional adsorbents, the adsorbent of this invention provides ultra-high adsorption capacity and selectivity through the synergistic effect of multiple mechanisms, including electrostatic adsorption, coordination complexation, hydrogen bonding, and reversible covalent bonding of borate ester bonds. It can achieve efficient desorption of dyes and recycling of materials, and efficiently and rapidly remove anionic dyes from water.

The application belongs to the technical field of battery recycling, and discloses a flotation depressant, a preparation method and application thereof. The flotation depressant comprises catechol, an oxidizing agent and a weak acid buffer solution, and the pH value of the flotation depressant is 4-6.5. The catechol and the oxidizing agent are dissolved in the weak acid buffer solution to prepare the flotation depressant, the flotation depressant can selectively inhibit the flotation of the positive electrode material, and thus the positive electrode material and the negative electrode material are separated through reverse flotation. The flotation depressant is used for flotation to obtain the positive electrode material rich in cobalt, and the grade and the recovery rate of the positive electrode material are as high as 90% and 83% respectively. The preparation method of the flotation depressant is simple, the cost is low, the flotation depressant is friendly to the environment, and the flotation depressant has a good application prospect in industrial battery recycling.

The application discloses a kind of full biological base adhesive based on epoxy soybean oil and preparation method thereof.Specifically, the method uses epoxy soybean oil as reaction base, citric acid as nucleophilic reagent to open the epoxy ring of epoxy soybean oil, tannic acid as catechol compound to provide adhesion after crosslinking polymerization, and constructs a biological base crosslinking network structure with excellent bonding performance. The present application is an environmentally friendly adhesive developed based on full biological base raw materials, with the outstanding features of non-toxic, renewable and environmentally friendly. The adhesive uses a one-pot synthesis process, which is simple and easy to implement industrial production. In terms of performance, it performs outstandingly, not only has excellent tensile strength and long-term stability, but also has outstanding water resistance and mildew resistance, making it stand out among similar products. In addition, the product has a wide range of raw materials, obvious cost advantage, and high performance and economic benefit.

The invention relates to a process for the synthesis of triglycidyl catechol based on eugenol. The object of the invention is to synthesize plastics, in particular epoxy resins, fiber-reinforced plastics, etc., based on renewable resources, especially for cabin construction in aviation, with a significantly increased bio-content. This object is achieved according to the invention by a process according to claim 1.

The invention belongs to the technical field of biofouling prevention sensors, and particularly relates to a polymer film sensing chip as well as a preparation method and application thereof. The polymer film sensing chip provided by the invention comprises a flexible substrate, an indicator electrode conducting layer, an indicator electrode sensing film, a reference electrode conducting layer, a reference electrode sensing film and a flexible packaging layer which are arranged on the surface of the flexible substrate, and a self-adhesion hydrogel layer arranged on the outermost layer, the material of the self-adhesion hydrogel layer comprises catechol type hydrogel, chitosan type adhesion hydrogel, polypeptide type hydrogel or hyaluronic acid type hydrogel. The self-adhesion hydrogel layer in the polymer film sensing chip provided by the invention contains a large number of hydrophilic functional groups and has excellent hydrophilic performance, and a water layer structure can be formed between the surface of the polymer film and fouling organisms so as to hinder the adhesion of the fouling organisms. The polymer film sensing chip provided by the invention has good ion permeability and mechanical strength, and can effectively inhibit adhesion of fouling substances.

This invention provides an injectable polyurethane material, its preparation method, and its applications, belonging to the field of injectable materials. The injectable polyurethane material has a cross-linked polyurethane structure and hydrophilicity. It is formed by polymerizing a polyethylene glycol-diisocyanate prepolymer, a cross-linking agent, and a chain extender. The cross-linking agent has a structure of Formula 1, and the chain extender has a structure of Formula 2. Specifically, this invention can employ a cross-linking agent containing a Schiff base and a chain extender with catechol as a side group, introducing both into a polyurethane network to form the injectable polyurethane material. In this invention, this cross-linked hydrophilic polyurethane can utilize the pH-responsiveness of the Schiff base to achieve controlled injection through secondary processing; moreover, it has good mechanical properties, facilitating its application.

The invention relates to the technical field of oilfield exploitation, and provides a self-healing gel plugging system with high wall surface binding capacity and a using method and application thereof.The plugging system is composed of self-healing gel, a wall surface binding agent and a self-healing inducer, and the wall surface binding agent serves as an intermediate to play a bridge role; a catechol group on one side of the nano-sheet has multiple interaction with active sites on the rock surface, and amino on the other side of the nano-sheet and an aldehyde group of a cross-linking agent form a Schiff base bond, so that a wall surface-nano-sheet-gel bridging structure is constructed, and a gel network is firmly anchored on the rock wall surface. The gel network can be crosslinked again to realize self-healing after being damaged by depending on an amino-aldehyde group dynamic reversible bond; the self-healing inducer gradually releases acidic components under stratum conditions, adjusts local pH, promotes aldehyde group-amino condensation crosslinking and improves the long-term stability of the system. Particle fluid channeling can be effectively inhibited, the water flooding swept volume is improved, and therefore the crude oil recovery rate is increased.

The invention relates to a body temperature-triggered adhesion degradable polyurethane patch as well as a preparation method and application thereof.The method comprises the steps that diisocyanate, semi-crystalline polyester diol, a carboxyl-containing chain extender and 3, 4, 5-trihydroxyphenylethylamine hydrochloride are taken as raw materials, and body temperature-triggered adhesion degradable polyurethane is synthesized through a condensation polymerization reaction; the degradable polyurethane is prepared into the degradable polyurethane adhesive patch capable of being triggered to be adhered by body temperature through a solution casting method. A polyester segment of the patch keeps high crystallinity at room temperature, a rigid physical cross-linked network is formed, molecular chain slippage and migration of catechol groups in 3, 4, 5-trihydroxyphenylethylamine hydrochloride are inhibited, and the patch does not show adhesion performance. At the body temperature, the crystalline region of the polyester segment is partially fused, the molecular chain segment obtains the movement ability to drive the suspended catechol group to migrate to the surface, the molecular thermal movement at the body temperature is intensified, the original hydrogen bond of the catechol is dissociated, and the catechol and the tissue surface form a hydrogen bond to realize adhesion. And stable and controllable degradation can be realized.

This invention relates to the field of adhesive technology, and discloses an environmentally friendly biomass-based underwater adhesive, its preparation method, and its applications. The adhesive is prepared by one-step melt copolymerization of three biomass raw materials: lipoic acid, caffeic acid, and cysteine. This system utilizes the ring-opening polymerization of lipoic acid to form a dynamic disulfide bond network providing cohesive force, the catechol groups of caffeic acid to provide various interfacial interactions with the substrate, and the thiol groups of cysteine ​​to simultaneously participate in network construction and inhibit catechol oxidation, thereby synergistically achieving high-strength and durable underwater adhesion. The adhesive achieves an underwater adhesion strength of up to 5.5 MPa on iron sheets, remains stable in various acid, alkali, and salt environments, and can be repeatedly recycled through hot melting. This invention uses entirely bio-based raw materials, employs a simple and non-toxic process, and is suitable for underwater remediation, marine engineering, and other fields.

The invention relates to the technical field of solid-state batteries, and provides a positive plate, a preparation method thereof and a solid-state battery. The positive plate comprises a positive current collector and a positive active material layer arranged on at least one side surface of the positive current collector; the positive electrode active material layer comprises a nickel-containing positive electrode active material, a solid electrolyte, a conductive agent and a binder; the binder comprises a first binder and a second binder; the first binder comprises polymer nanofibers, and the length-diameter ratio of the polymer nanofibers is 30-90; the mass ratio of the first binder in the positive active material layer is 0.8%-5%; the second binder includes a catechol group-containing polymer. According to the invention, the first binder and the second binder are combined for use to form a tough composite adhesion system, so that the adhesion of the positive plate is remarkably improved, and the high and low temperature performance and flexibility of the solid-state battery are improved.

The invention discloses a sprayable hydrogel composite coating and a preparation method thereof in the field of functional polymer coating materials. The preparation method of the coating comprises the following steps: synthesizing two key compounds: one is a double-dynamic silane cross-linking agent containing catechol and boric acid ester; the adhesive is prepared by esterifying and deprotecting a phenylboronic acid ester derivative and then reacting with a silane coupling agent, and simultaneously provides strong adhesion and dynamic cross-linking capability; and the sulfobetaine-Schiff base bifunctional antibacterial monomer is prepared from a betaine monomer and natural aldehyde through dehydration condensation, and has anti-fouling and antibacterial functions. When the coating is prepared, the acrylamide, the acrylic acid, the antibacterial monomer, the hydrophobic nanoparticles and the photoinitiator are dispersed in a solvent, then the cross-linking agent is added and mixed, a precursor solution is obtained, and the coating is obtained after spraying and ultraviolet curing. The coating prepared by the method shows excellent adhesion, good toughness and long-acting antibacterial and antifouling properties, and is suitable for multiple fields of biomedicine, marine antifouling and the like.

The application discloses a high-temperature-resistant polyvinyl chloride adhesive tape and a preparation method thereof, and belongs to the technical field of polymer materials and adhesive products. The high-temperature-resistant polyvinyl chloride adhesive tape comprises the following raw materials in parts by weight: synergistically modified polyvinyl chloride, diphenyl phosphine oxide, chlorinated polyethylene, diisononyl phthalate, antimony trioxide, calcium stearate, zinc stearate, an antioxidant and a leveling agent; the synergistically modified polyvinyl chloride is obtained by introducing catechol structures on the surface of polyvinyl chloride through dopamine self-polymerization deposition, forming a dynamic borate ester structure with 3-aminobenzoic acid, and constructing a Si-O-Si network structure through hydrolytic condensation reaction of octa(3-aminopropyl)silsesquioxane and N-(beta-aminoethyl)-gamma-aminopropyl triethoxysilane. The dopamine-borate ester-silicone synergistic network structure is constructed, and the diphenyl phosphine oxide is introduced for function regulation, so that the heat resistance, mechanical properties and dimensional stability of the polyvinyl chloride adhesive tape are significantly improved.

The invention discloses a bio-enzyme preparation for catalytic degradation of grease as well as a preparation method and application thereof, and belongs to the technical field of bio-enzymes. The gel carrier is formed by cross-linking a chitosan-lauric acid-dopamine conjugate and Fe < 3 + > ions through covalent coupling; the bonding adaptive compound enzyme is a mixed enzyme of which the surface is grafted with a catechol group through an N-hydroxysuccinimide-dopamine ester modifier; the technical bottleneck that efficient catalysis, firm fixation, convenient recovery and long-acting stability of an industrial cleaning enzyme preparation are difficult to consider at the same time is solved, and the prepared biological enzyme preparation has the high-activity recovery rate, excellent recycling stability, intelligent separation and recovery characteristics and efficient broad-spectrum cleaning capacity; and the method has remarkable industrial application advantages and market competitiveness.

The present application relates to a kind of synthetic hydroxytyrosol multi-enzyme catalytic method.The synthetic hydroxytyrosol multi-enzyme catalytic method described in the present application includes first module reaction, second module reaction, third module reaction in turn;The first module reaction is that glycerol is synthesized pyruvic acid by catalysis, wherein the concentration of the glycerol is 1-5mM;The second module reaction is that pyruvic acid is condensed with catechol and ammonium chloride to be L-levodopa by catalysis;Wherein, the concentration of the catechol is 1-5mM, and the concentration of the catechol is greater than the concentration of the glycerol in the first module reaction;The third module reaction is that L-levodopa is synthesized hydroxytyrosol by catalysis.The synthetic hydroxytyrosol multi-enzyme catalytic method described in the present application, reaction 4 hours hydroxytyrosol molar conversion rate can reach 71.5%, compared with one-pot method has obvious advantage, in the same reaction time molar conversion rate is compared with one-pot method and increased nearly 6 times.

The invention discloses an environment-friendly bio-based chinlon core-spun yarn and a preparation method thereof, and belongs to the technical field of bio-based high polymer materials and functional textile materials. The chinlon core-spun yarn comprises synergistically modified bio-based nylon-6, ellagic acid, an antioxidant, nano titanium dioxide, an antistatic agent and a lubricant; wherein the synergistically modified bio-based nylon-6 is a multi-network synergistically enhanced system formed by in-situ construction of a boron-oxygen heterocyclic structure, a dynamic sulfydryl exchange structure and an interface anchoring structure by bio-based nylon-6, phenylboronic acid, catechol, 2, 3-dimercaptosuccinic acid and gamma-aminopropyltriethoxysilane under a melting condition; the ellagic acid participates in the interchain multiple hydrogen bond and pi action through the rigid polyphenol conjugated structure of the ellagic acid, so that molecular-level synergistic regulation is realized. Under the condition of not increasing the load of the inorganic filler, the tensile strength and the thermal stability of the yarn are remarkably improved, the thermal shrinkage rate is reduced, the ultraviolet resistance and the thermo-oxidative aging durability are improved, and good environmental friendliness and industrial application prospects are achieved.

The invention discloses a preparation method of a Zn0. 3Cd0. 7S (at) CFR heterojunction photocatalyst, which comprises the following steps: firstly, preparing a Zn0. 3Cd0. 7S catalyst by a hydrothermal method, and dispersing the Zn0. 3Cd0. 7S catalyst in ultrapure water; then, catechol, ammonia water and formaldehyde are sequentially added into the dispersion liquid, CFR evenly grows on the surface of Zn0. 3Cd0. 7S through a hydrothermal reaction, a coating layer is formed, and a final product is obtained after washing and drying. The preparation method is simple, the process is easy to control, and the prepared photocatalyst shows excellent H2O2 yield and good cycle stability under the condition that a sacrificial agent is not added.

The application discloses a method for constructing a social novelty defect model through catechol exposure of pregnant mice, and belongs to the technical field of disease animal models. The method comprises the following steps: performing catechol exposure treatment on the pregnant mice, feeding the pregnant mice until childbirth, and waiting for the obtained offspring mice to grow to a required age, so as to obtain the social novelty defect model. The method is capable of precisely matching a key time window of embryonic neural development, and adopts a single catechol exposure mode, so that the method is simple to operate, has a high model formation rate, and has a high survival rate of the mother mice and the offspring. In addition, the induced social novelty defect model of the offspring mice is stable in phenotype and strong in specificity, can simulate the cross-generation influence of maternal pregnancy environment exposure on abnormal social functions of offspring young, and is suitable for mechanism research, drug screening and diagnosis marker development of social impairment diseases such as autism.

The invention discloses high-performance LCP (Liquid Crystal Polymer) resin and a preparation method thereof, and relates to the technical field of LCP resin. According to the preparation method, p-hydroxybenzoic acid, p-tert-butylcatechol and 5-vinyl isophthalic acid are taken as key monomers, LCP base resin with a side chain containing double bonds and tert-butyl is synthesized, then the LCP base resin and alkenyl-terminated polyarylester are subjected to melt extrusion, and the high-performance LCP resin is prepared. According to the present invention, the polyarylester and the alkenyl-terminated polyarylester form the micro-cross-linked structure during the processing, such that the excessive orientation of the molecular chain is effectively inhibited, the anisotropy is reduced, the melt strength and the processability are significantly improved, and the obtained resin has characteristics of high mechanical property and improved toughness, and is especially suitable for preparing the high-performance LCP material.

The invention relates to the technical field of degradable high polymer materials and disposable personal care products, and discloses a preparation process of a degradable high-barrier plastic film for a hair dyeing shawl, and the preparation process comprises the following steps: 1, preparing chitosan-dopamine grafted modified montmorillonite (CTS-DA-MMT): dispersing 5g of 20-30nm nano montmorillonite in a 2wt% acetic acid solution, and ultrasonically dispersing for 40 minutes by 200W; adding dopamine hydrochloride according to the ratio of montmorillonite to dopamine being 1: 0.2, adjusting the pH value to 8.5 by using 1mol / L NaOH, and carrying out stirring reaction at room temperature for 1 hour; adding chitosan according to the ratio of montmorillonite to chitosan being 1: 0.4, and stirring and reacting at the constant temperature of 50 DEG C for 3 hours; the pH is adjusted to 7.0 through 1 mol / L HCl, centrifugation is carried out for 15 min at the speed of 8000 r / min, washing is carried out three times through deionized water, vacuum drying is carried out for 8 h at the temperature of 60 DEG C, and the product is obtained. According to the preparation technology of the high-barrier plastic film for the degradable hair dyeing shawl, chemical grafting (instead of physical blending) of montmorillonite-dopamine-chitosan is achieved through catechol groups of dopamine, the problems of montmorillonite agglomeration and matrix compatibility are solved, and the degradable hair dyeing shawl is prepared. Meanwhile, through the dynamic adhesiveness of dopamine, the problem of barrier failure under dynamic stretching is solved.

This invention discloses an ultra-high performance fiber-reinforced concrete and its preparation method, belonging to the field of concrete technology. By acid etching of high-silica glass fibers with sulfuric acid and nitric acid, the surface roughness of the fibers is increased, and a large number of active groups such as hydroxyl groups are introduced, providing reaction sites for subsequent dopamine grafting. This solves the problems of strong surface inertness and weak interfacial bonding between glass fibers and the concrete matrix. Compared with traditional concrete, the internal structure is highly dense, with high compressive strength and is not easily corroded by alkaline media. Furthermore, this invention forms a highly active adhesive coating on the fiber surface by covalently bonding the catechol groups of dopamine with the hydroxyl groups on the fiber surface. Simultaneously, the amino and phenolic hydroxyl groups of the dopamine coating act as bridges, enhancing the bonding force between the fiber and subsequent silanes and bentonite, significantly improving the interfacial compatibility between the fiber and the concrete matrix, and reducing the risk of interfacial debonding under stress.

The present invention relates to a levan-catechol composite, and a tissue adhesion composition and nanocluster, including same. In particular, the levan-catechol composite is prepared by the conjugation of levan and catechol and is applicable, by hydrogelation or nanoclustering thereof, for use in tissue adhesion in wet environments, wound healing, hemostasis, or drug delivery.

The present invention relates to lignin comprising beta-O-4'units bound in position to one or more compounds of formula (I), such as phenol, catechol, resorcinol, hydroquinone, pyrogallol and / or guaiacol, a process for its preparation and its use. And lignin fragment 1.

This invention relates to a mesoporous single-atom iron nanoparticle self-catalyzing material, its preparation method, and its application. The mesoporous single-atom iron nanoparticle self-catalyzing material comprises: a mesoporous polydopamine framework, and Fe metal catalytic centers chelated in the mesoporous polydopamine framework in the form of single atoms; the mesoporous polydopamine framework has catechol functional groups.