70 results about "Grafted chitosan" patented technology

The invention discloses a bacteriostatic food packaging bag and a preparation method thereof, and relates to the technical field of food packaging, the bacteriostatic food packaging bag comprises the following components by weight: 12-22 parts of bamboo fiber; 55 to 80 parts of TPS (Thermoplastic Polystyrene); 15-20 parts of a modified ethylene composite copolymer; 15 to 20 parts of modified chitosan; wherein the modified ethylene composite copolymer is obtained by polymerizing active group-containing ethylene and one of vinyl acetate, butene, hexene or octylene according to a molar ratio of 10: (3-6); the active group is at least one of amino and sulfonic acid group; the modified chitosan is sulfo-grafted chitosan, and the mass grafting rate is greater than 0.1 wt%. The preparation method has the advantages that the compatibility of a composition formula is improved through the modified ethylene composite copolymer and the modified chitosan, a uniform net structure is formed in a cross-linking reaction to serve as a supporting framework, the overall mechanical structure performance is enhanced through the bamboo fibers which are synergistically and uniformly distributed in the composition formula, and the degradable and non-toxic effects are achieved through the cooperation of the bamboo fibers and the TPS.

The invention relates to a hydrogel dressing based on near-infrared light controllable cascade reaction and a preparation method thereof, and belongs to the technical field of hydrogel dressings. The preparation method of the hydrogel dressing based on the near-infrared light controllable cascade reaction comprises the following steps: respectively grafting carboxymethyl-beta-cyclodextrin and L-arginine to carboxymethyl chitosan by adopting an EDC / NHS crosslinking method to prepare cyclodextrin grafted chitosan and L-Arg grafted chitosan; adding a photosensitizer into the cyclodextrin grafted chitosan solution I to obtain a C-C-I inclusion compound solution; adding hemin into the cyclodextrin grafted chitosan solution II to obtain a C-C-H inclusion compound solution; and mixing the oxidized hyaluronic acid solution, the L-Arg grafted chitosan solution, the C-C-I clathrate compound solution and the C-C-H clathrate compound solution. The CLIHO disclosed by the invention can be used for synergistically resisting bacteria through PTT / NO and synchronously adjusting a wound microenvironment, so that the healing speed and the healing quality of infectious chronic wounds are improved.

The invention discloses a biochar-based soil improvement fertilizer and a preparation method thereof, and belongs to the technical field of agricultural fertilizers, the biochar-based soil improvement fertilizer comprises the following components by weight: 50-70 parts of modified biochar; 10-15 parts of a chemical fertilizer; a chitosan chain segment and an amino acid polymer chain segment are grafted on the modified charcoal; the raw materials of the modified biochar comprise biochar, chitosan and an amino acid polymer in a mass ratio of 1: (0.1-0.3): (1.5-2.5). In addition, the biochar-based soil improvement fertilizer also comprises 3-4 parts of zinc humate. According to the biochar-based soil improvement fertilizer disclosed by the invention, the adsorption capacity and anti-saturation capacity of biochar to anions and cations are improved, and meanwhile, the biochar-based soil improvement fertilizer is endowed with excellent soil hardening resistance and water and fertilizer retention performance, so that synergism and unification of soil improvement and efficient utilization of nutrients are realized.

The invention relates to an antibacterial sanitary towel containing traditional Chinese medicinal materials. The antibacterial sanitary towel containing the traditional Chinese medicinal materials structurally and sequentially comprises a soft cotton layer, a modified bamboo fiber layer, a traditional Chinese medicine extract layer, an absorption layer and a bottom layer. Wherein the modified bamboo fiber is obtained by reacting a reaction product of oxidized bamboo fiber and chitosan with polydopamine. Firstly, sodium periodate is utilized to oxidize bamboo fibers to introduce aldehyde groups, then chitosan is grafted, and finally the chitosan reacts with polydopamine to form a three-dimensional network structure, so that the antibacterial property of the sanitary napkin is remarkably improved. Meanwhile, the traditional Chinese medicine extract is loaded on the PP non-woven fabric. The instant antibacterial effect of the modified bamboo fiber and the slow-release antibacterial effect of the traditional Chinese medicine extract are combined, and the synergistic antibacterial effect is achieved; due to the unique structural design, the sanitary towel has the advantages of rapid flow guide, lasting bacteriostasis and skin safety, and the use performance and comfort of the sanitary towel are comprehensively improved.

The invention relates to a composite acidifying agent for improving feed intake of lactating sows and a preparation method thereof, and belongs to the technical field of feed additives. The composite acidifier comprises a wall material and a core material, wherein the wall material comprises cystine-gamma-polyglutamic acid and arginine-chitosan; the core material comprises organic acid, organic acid salt and fermentation liquor. According to the compound acidifying agent disclosed by the invention, the cystine cross-linked gamma-polyglutamic acid and the arginine grafted chitosan are used as wall materials, and the microcapsule with an intestinal targeted release function is formed by wrapping the organic acid, so that the utilization efficiency of the acidifying agent and the feed intake of lactating sows can be effectively improved.

The present application relates to the technical field of medical materials, and discloses a medical sterilization fiber dressing and a preparation process thereof. The dressing comprises a functional substrate and an electrochemically active component. The functional substrate comprises cyclodextrin grafted chitosan and sodium alginate, and the electrochemically active component comprises zinc powder and copper powder. The dressing utilizes the zinc powder and copper powder to form a micro-battery in an electrolyte environment, releases zinc ions and generates a micro-electric field to kill bacteria. At the same time, the cavity structure of the cyclodextrin grafted chitosan specifically recognizes and includes wound infection markers, and then regulates the reaction rate of the micro-battery, so as to realize the on-demand release of sterilization activity. The preparation process comprises the following steps: mixing the components to prepare a spinning solution, forming in a calcium chloride solution through wet spinning, and then stretching and drying to obtain the fiber dressing. The dressing can respond to the wound infection state, realize on-demand sterilization, and has good biocompatibility.

The invention belongs to the technical field of biomedical materials, and discloses a patch for repairing dural mater damage as well as a preparation method and application of the patch. The invention provides a patch for repairing damage of an epidural mater. The patch comprises a substrate layer and an adhesion layer, the substrate layer is a poly-L-lactic acid fiber film; the adhesion layer is prepared from acrylic acid, chitosan grafted with levodopa, 2-(acryloyloxy) ethyl trimethyl ammonium chloride, a photoinitiator and a cross-linking agent. The patch for repairing the dura mater injury has the functions of low swelling, long-acting adhesion, fibrosis resistance, oxidation resistance, inflammation resistance and the like, can meet the clinical treatment requirements for repairing the dura mater injury and long-acting sealing, and is suitable for the field of medical materials.

The invention relates to the technical field of degradable films, and particularly discloses a long-acting antibacterial degradable film material and a preparation method thereof. The long-acting antibacterial degradable film material is prepared from the following raw materials in parts by weight: 40 to 80 parts of matrix resin, 15 to 35 parts of hydrophobic modified chitosan, 5 to 10 parts of antibacterial agent master batch and 5 to 10 parts of reinforcing agent, the hydrophobic modified chitosan is stearaldehyde grafted chitosan at polylactic acid, and the antibacterial agent master batch is siloxane modified dioctadecyl dimethyl ammonium methyl carbonate at polylactic acid. The material can be well compatible with a hydrophobic polymer matrix, migration and loss of antibacterial components can be inhibited, long-acting stable antibacterial performance is achieved, good mechanical performance and barrier performance are kept, meanwhile, environment degradability of the whole life cycle is ensured, and therefore the urgent requirement of modern green packaging for high-performance, multifunctional and sustainable materials is met.

The invention belongs to the technical field of adhesive materials, and particularly relates to a modified starch-based water-based adhesive as well as a preparation method and application thereof. According to the adhesive, oxidized corn starch is taken as a base material, hydrophobic and weather-resistant modification is realized by introducing a fluorine-silicon-containing functional monomer, and hydroxypropyl quaternized chitosan is compounded to endow antibacterial property and a film-forming enhancement effect; a borax cross-linked polyol system is supplemented to improve the cohesive strength, and a plasticizer, a thickening agent and an emulsifier are matched to optimize the rheological property and wettability. The preparation process comprises the steps of starch gelatinization, fluorosilicone urea grafting, chitosan derivative compounding, auxiliary agent blending and the like, and the process is mild, environment-friendly and non-toxic. The obtained water-based adhesive has the characteristics of strong initial adhesion, good water resistance, moderate flexibility, excellent biocompatibility and the like, and is especially suitable for adhesion and manufacturing of ball products such as basketballs, footballs and the like.

A method for preparing silkworm pupa active peptide microcapsules and their applications are disclosed. In a microfluidic focusing droplet generation chip, an aqueous phase is injected into the chip through the main channel, and an oil phase is injected through two side channels. The resulting microdroplets are collected in the collecting phase to form microcapsules. The filter membrane has a pore size of 0.1-1 μm. The aqueous phase consists of sodium alginate and silkworm pupa protein peptides; the oil phase consists of one of mineral oil, soybean oil, silkworm pupa oil, corn oil, peanut oil, rapeseed oil, and lard; the collecting phase consists of caffeic acid-grafted chitosan and calcium chloride dissolved in acetic acid. By optimizing the formulation and process, droplets with good dispersibility in oil, uniform morphology and size, and good stability are prepared.

The invention discloses an antibacterial and anti-algae PP composite board and a preparation method and application thereof.The antibacterial and anti-algae PP composite board comprises a polypropylene composite material layer, a glass fiber reinforcement layer and an antibacterial layer which are sequentially stacked, the antibacterial layer comprises antibacterial master batch, the antibacterial master batch is of a core-shell structure, a maleic anhydride grafted polypropylene resin material serves as a shell layer, and the shell layer is made of a polypropylene resin material; a mixed filler formed by quaternary ammonium salt grafted chitosan and nano zinc oxide is used as an inner core. The antibacterial and anti-algae PP composite board provided by the invention has excellent antibacterial and anti-algae capabilities, and has excellent mechanical properties and weather resistance.

The invention relates to the technical field of pesticide preparations, in particular to a method for improving uniformity of a carbendazim suspending agent. The method comprises the following steps: mixing a carbendazim active compound, a modified dispersant, a wetting agent and part of deionized water, and carrying out shearing pre-dispersion and sanding grinding to prepare superfine slurry; adding the antifreeze agent, the thickening agent and the defoaming agent, uniformly stirring, adding the balance of water to adjust the solid content and the pH value, filtering out impurities, and intermittently stirring and curing to obtain a final suspending agent product. The modified dispersant is prepared by esterifying allyl polyoxyethylene ether and succinic anhydride, then copolymerizing with 2-ethylhexyl acrylate and acrylamide, grafting chitosan quaternary ammonium salt and inclusion cyclodextrin, and the steric hindrance and anchoring stability are remarkably enhanced; the thickening agent is a compound system of xanthan gum and magnesium aluminum silicate. According to the method, the uniformity and redispersibility of the preparation are effectively improved, Ostwald ripening and crystal growth are inhibited, and the physical stability and efficacy consistency of the product in the long-term storage and use process are guaranteed.

The invention discloses a crown ether grafted chitosan coating film and a preparation method and application thereof.According to the coating film, chitosan serves as a base material, crown ether serves as a functional modifier, a matrix polymer serves as a coating matrix, NPOE serves as a plasticizer, and a PIM-CTS-15 coating film and a PIM-CTS-18 coating film are prepared through chitosan precursor preparation, crown ether grafting modification, film casting liquid preparation and coating forming; and the crown ether is benzo 15-crown-5 or dibenzo 18-crown-6. The invention further discloses a preparation method of the catalyst. Through the synergistic effect of specific recognition, hydrophilic regulation and structure enhancement, the coating film has high selectivity, high permeation flux and good stability on lithium ions. The membrane is simple in preparation process and easy to industrialize, can be efficiently used for lithium separation and extraction of lithium-containing waste liquid, and has remarkable economic and environmental benefits.

The invention discloses an injectable bone repair material and a preparation method thereof, and belongs to the technical field of biological materials. The material is characterized in that N-formylglycine, allyl lactate and S-allylcysteine react and then react with chitosan to obtain grafted chitosan, the grafted chitosan, methacrylated gelatin and icariin-naringenin lipidosome are formed, and the stable three-dimensional interpenetrating network structure hydrogel is formed through photocuring. The preparation method comprises the following steps: firstly synthesizing grafted chitosan, then preparing icariin-naringenin liposome, finally mixing a grafted chitosan solution, a methacrylated gelatin solution and liposome, adding a photoinitiator, and carrying out ultrasonic degassing and ultraviolet curing to obtain a finished product. The material utilizes thioether bonds to realize active oxygen responsive drug intelligent release, liposome encapsulation improves the drug utilization rate, a double-network structure endows the material with excellent injectability, mechanical strength and biocompatibility, and the material can effectively adapt to irregular bone defects and promote bone regeneration.

The invention relates to the technical field of hemostatic materials, and provides chitosan-based in-situ self-gel powder as well as a preparation method and application thereof. The chitosan-based in-situ self-gel powder provided by the invention comprises modified chitosan-based powder and oxidized polysaccharide powder, the modified chitosan-based powder is prepared from poly (3-sulfopropyl methacrylate potassium salt) grafted chitosan and poly [2-(methylacryloyloxy)-ethyltrimethyl ammonium chloride] grafted chitosan. The chitosan-based in-situ self-gelling powder provided by the invention has an in-situ self-gelling function, can quickly absorb water to realize self-gelling under the triggering of body fluid or blood, has excellent wet tissue adhesion performance, is high in water absorption speed and good in hemostatic effect, is not influenced by a normal blood coagulation mechanism in a hemostatic process, and has good postoperative anti-adhesion performance; no chemical cross-linking agent is used in the preparation process of the chitosan-based in-situ self-gel powder, the chitosan-based in-situ self-gel powder has good biocompatibility and biodegradability, raw materials are easy to obtain, synthesis is simple, and the chitosan-based in-situ self-gel powder is economical and safe.

The invention provides a copper ion imprinted cross-linked grafted chitosan adsorbent and a preparation method thereof. The preparation method comprises the following steps: adding an initiator into a mixed solution of a copper ion template agent and a chitosan solution to obtain a first reaction solution; carrying out grafting reaction on the first reaction solution to obtain a second reaction solution; adding a cross-linking agent into the second reaction liquid, carrying out cross-linking curing, and carrying out solid-liquid separation to obtain an intermediate; and eluting the copper ions in the intermediate to obtain the copper ion imprinted cross-linked grafted chitosan adsorbent. A solvent of the chitosan solution comprises water and unsaturated carboxylic acid. According to the preparation method disclosed by the invention, an ion imprinting technology is combined with crosslinking and grafting modification, so that the copper ion imprinting crosslinking grafted chitosan adsorbent is endowed with higher stability and selectivity, and the cyclic regeneration performance of the copper ion imprinting crosslinking grafted chitosan adsorbent is improved; the adsorption kinetics and the adsorption thermodynamics of the copper ion imprinted cross-linked grafted chitosan adsorbent are optimized.

The invention provides a flame-retardant master batch and a preparation method thereof. The master batch is composed of 45-70% of matrix resin, 25-40% of a composite flame retardant, 3-12% of a dynamic cross-linking agent and 2-7% of a processing aid, the composite flame retardant provides phosphorus-nitrogen synergistic flame retardant activity through phosphate grafted chitosan, physical protection is achieved by coating a polyurethane packaging layer, and flame retardant migration and interface degradation are effectively prevented. The epoxy prepolymer is used as a dynamic cross-linking agent to regulate and control the rheological behavior of the material: dynamic bond dissociation reduces the melt viscosity during processing, bond recombination enhances the toughness after molding, and meanwhile, the master batch is endowed with self-repairing capability. The preparation method comprises the steps of in-situ packaging, segmented melt blending and dynamic crosslinking extrusion, flame retardant dispersion and control over a crosslinking network are achieved through temperature gradient and mechanical shearing, the contradiction between the mechanical property and the flame retardant property of a traditional flame retardant system is broken through, and the excellent processing stability is achieved.

This invention relates to the field of water pollution control technology and discloses the preparation and application of modified chitosan adsorption balls. The invention involves grafting modified nano-micron high-purity composite active iron onto chitosan, then mixing it with dried and crushed sludge. The modified nano-micron high-purity composite active iron is then reacted with the chitosan to modify it. First, the surface of the nano-micron high-purity composite active iron is made to have active functional groups, and then it reacts with chitosan. At this point, the chitosan also has a dispersing effect, resulting in better performance and achieving a synergistic effect of dual phosphorus removal. This invention has low cost, simple operation, and good economic benefits.

The invention discloses an amphoteric polyether modified chitosan quaternary ammonium salt leveling agent as well as a preparation method and application thereof. The preparation method of the amphoteric polyether modified chitosan quaternary ammonium salt leveling agent comprises the following steps: dissolving chitosan in an acetic acid solution, and adding an oxidizing agent for degradation to obtain a low-molecular-weight chitosan solution; adding a cationic etherifying agent into the low-molecular-weight chitosan solution, and carrying out heating reaction under an alkaline condition to obtain a chitosan quaternary ammonium salt solution; adding epoxy-terminated polyether into the chitosan quaternary ammonium salt solution to obtain a polyether grafted chitosan quaternary ammonium salt solution; adding succinic anhydride into the polyether grafted chitosan quaternary ammonium salt solution for acylation reaction to obtain an amphoteric polyether modified chitosan quaternary ammonium salt solution; and concentrating the amphoteric polyether modified chitosan quaternary ammonium salt solution, adding water, and uniformly mixing to obtain the amphoteric polyether modified chitosan quaternary ammonium salt leveling agent. The amphoteric polyether modified chitosan quaternary ammonium salt leveling agent disclosed by the invention has excellent leveling property, retarding property and migration property in anionic dye dyeing.

The application discloses a kind of two-component modified binary polymer nanofiber array and its molecular model, preparation method and application, two-component modified binary polymer includes polyvinyl alcohol, chitosan, carbon nanotube, silver particle four components.Polyvinyl alcohol is grafted chitosan with hydrogen bond, polyethylene-chitosan is grafted carbon nanotube with covalent bond, silver particle is dispersed and supported in the gap and surface of polyethylene-chitosan-carbon nanotube nanofiber array.Polyvinyl alcohol and chitosan binary polymer have high interface affinity and stability, carbon nanotube has the function of dispersing binary polymer and electrical conductivity, silver component has electrocatalytic activity and electrical conductivity function, the two-component modified binary polymer nanofiber array obtained by the application has electrocatalytic reduction hydrogen peroxide, is applied to the construction of electrochemical sensor, realizes the high sensitivity and high stability detection hydrogen peroxide performance.

The invention relates to a bacterial cellulose capsule. The bacterial cellulose capsule is prepared from the following raw materials: a fermented fiber beverage, a konjac glucomannan solution and a gallic acid grafted chitosan oligosaccharide solution, in the fermented fiber beverage, the concentration of bacterial cellulose is 0.5-1.5 g / mL; the bacterial cellulose is obtained by fermenting and purifying gluconacetobacter xylinum and foal bacillus; in the konjac glucomannan solution, the concentration of konjac glucomannan is 5 to 15 mg / mL; in the gallic acid grafted chitosan oligosaccharide solution, the concentration of gallic acid grafted chitosan oligosaccharide is 5 to 15 mg / mL. The swelling ratio of the capsule is gt; the structural integrity can be maintained after water absorption and expansion, and the fiber suspension can be gradually dispersed into the fiber suspension at proper time and can be conveniently discharged out of the body.

The invention belongs to the technical field of wound dressings, and discloses a hydrogel dressing with antibacterial and scar-preventing effects and a preparation method thereof.3-fluoro-4-carboxyphenylboronic acid grafted chitosan oligosaccharide is introduced, phenylboronic acid bonds are matched with a large number of catechol structures in a tannic acid solution to form dynamic boron ester bonds, and the dynamic boron ester bonds are grafted to the chitosan oligosaccharide; the preparation method comprises the following steps: carrying out joint response with supramolecular forces such as hydrogen bonds to form a network gel structure, enabling boron ester bonds to respond to a high ROS level of a wound microenvironment and an acidic environment caused by bacterial infection to break, so as to efficiently release cyclooxygenase-2 selective non-steroidal anti-inflammatory drug celecoxib, and enabling the vinipofen liposome to be limited by a relatively large volume, so that the vinipofen liposome has a good anti-inflammatory effect. The time of staying in the dressing is longer, and continuous and stable release can be maintained in the whole wound healing process range, so that the effects of on-demand inflammation regulation and control and long-acting mechanical response regulation and control are achieved.

This invention discloses an injectable bone repair material and its preparation method, belonging to the field of biomaterials technology. The material is composed of grafted chitosan obtained by reacting N-formylglycine, allyl lactate, and S-allyl cysteine ​​with chitosan. The grafted chitosan, methacrylamide gelatin, and icariin-naringenin liposomes are then photocured to form a stable three-dimensional interpenetrating network hydrogel. The preparation method includes: first synthesizing grafted chitosan, then preparing icariin-naringenin liposomes, and finally mixing the grafted chitosan solution, methacrylamide gelatin solution, and liposomes, adding a photoinitiator, and then ultrasonically degassing and ultraviolet curing to obtain the finished product. This material utilizes thioether bonds to achieve intelligent drug release in response to reactive oxygen species, and liposome encapsulation improves drug utilization. The dual-network structure endows it with excellent injectability, mechanical strength, and biocompatibility, effectively adapting to irregular bone defects and promoting bone regeneration.

The utility model relates to a wool fiber grafting chitosan reaction device which comprises a device support, the device support comprises an outer side container with an opening in the upper side, an inner side container with an opening in the upper side is rotationally assembled at the bottom of the outer side container, and a rotating sleeve rotationally matched with the bottom of the outer side container is arranged at the bottom of the inner side container. A water passing hole is formed in the container wall of the inner side container, a water inlet is formed in the top of the outer side container, a water outlet is formed in the bottom of the outer side container, a stirring shaft is rotationally assembled at the bottom of the inner side container, the lower end of the stirring shaft penetrates out of the lower side of the rotating sleeve, and a first motor in transmission connection with the penetrating-out end of the stirring shaft is arranged at the bottom of the outer side container. A second motor in transmission connection with the rotating sleeve is further arranged at the bottom of the outer side container. The device solves the technical problem that in the prior art, after the reaction time of wool and an oxidizing agent is up, the wool and the oxidizing agent cannot be rapidly separated.

The application discloses an environment-friendly water-based ink and a preparation method thereof, and belongs to the technical field of inks. The environment-friendly water-based ink comprises, in weight parts, 85-95 parts of a composite emulsion, 8-10 parts of a color paste, 3-5 parts of a dispersing agent, 2-5 parts of grafted chitosan nano-cellulose, 1-3 parts of hexamethyldisilazane modified mesoporous silica and 0.5-2 parts of nano-zinc oxide. In addition, the application further provides a preparation method of the environment-friendly water-based ink, which comprises the following steps: mixing and stirring the composite emulsion, the color paste, the dispersing agent, the grafted chitosan nano-cellulose, the hexamethyldisilazane modified mesoporous silica and the nano-zinc oxide, and then performing homogenization treatment to obtain the environment-friendly water-based ink. The water-based ink provided by the application has the advantages of fast drying and excellent aging resistance.

The present application relates to a kind of dolasetron mesylate suppositories, it is characterized in that, component includes: dolasetron mesylate, cyclodextrin or its derivative, shell matrix, hardness regulator, gel matrix, water;The gel matrix includes polyacrylic acid derivative grafted chitosan in it.The present application uses polyacrylic acid derivative grafted chitosan and cyclodextrin to prepare dolasetron mesylate liquid gel, significantly improve the stability and bioavailability of suppository;And can achieve the purpose of quick effect and slow release long-acting simultaneously.The suppository of the present application is very convenient for old people, children or patients who cannot be administered orally, and the treatment population of the product belongs to the patient who is inconvenient to swallow.

This application discloses a method for preparing a waterproof and breathable membrane for outdoor clothing, relating to the field of clothing and apparel technology. The method includes the following steps: Step 1, spinning solution preparation: mixing and stirring a polymer resin with a solvent to prepare a spinning solution; Step 2, electrospinning: introducing the spinning solution obtained in Step 1 into an electrospinning machine, and obtaining a waterproof and breathable membrane preform through the spinning process; wherein the polymer resin includes TPU or PU, maleic anhydride-grafted chitosan and / or modified high-sodium bentonite, and phase change temperature-regulating microcapsules, and the maleic anhydride-grafted chitosan and / or modified high-sodium bentonite account for 3-12% of the mass of the polymer resin, and the phase change temperature-regulating microcapsules account for 20-42% of the mass of the polymer resin. This application achieves efficient and intelligent temperature control by combining maleic anhydride-grafted chitosan and phase change temperature-regulating microcapsules, thereby improving the compatibility of the phase change temperature-regulating microcapsules in the polymer resin and uniformly dispersing them in the polymer resin.

This invention discloses an antibacterial composite material of nano-silver / chitosan nanofiller doped with polymer and its preparation method, belonging to the field of antibacterial composite material technology. This invention modifies chitosan through amphiphilic grafting, simultaneously grafting hydrophobic segments compatible with the polymer matrix and hydrophilic groups with strong coordination ability to silver ions, forming a "molecular bridge" structure. Subsequently, the amphiphilic grafted chitosan is uniformly dispersed with plasma-pretreated polymer resin and silver precursor in a deep eutectic solvent, and nano-silver is generated by in-situ reduction, effectively solving the problems of nanoparticle aggregation and interfacial compatibility. Based on this, an antibacterial composite material with both long-lasting antibacterial effect and excellent mechanical properties is obtained through melt blending and injection molding.

The present application provides a method for isolating and purifying a polypeptide with antioxidant function, a polypeptide, and its preparation and application. The method comprises the following steps: S1, scrubbing animal bones with a multi-brush roller staggered scrubbing device; S2, rinsing, enzymatic hydrolysis, and ultrafiltration after scrubbing to produce a bone peptide solution; S3, mixing the bone peptide solution, chlorogenic acid-grafted chitosan, and transglutaminase, reacting, inactivating the enzyme, and dialyzing. After dialysis, the mixture is dried to produce an antioxidant polypeptide; the mass ratio of the chlorogenic acid-grafted chitosan to transglutaminase is 1:0.2-0.3; and the mass-to-volume ratio of the chlorogenic acid-grafted chitosan to the bone peptide solution is 1g:50mL-100mL. The functional polypeptide produced using the method of the present application has excellent antioxidant function.

The application relates to the technical field of PET polyester, and discloses a preparation method of a degradable PET composite material for blister packaging. 100 parts by weight of polyethylene terephthalate, 1.2-4 parts by weight of a polyester quaternary ammonium salt grafted chitosan are added into a double-screw extruder, melt extruded, and cut into particles to obtain the degradable PET composite material for blister packaging. The chitosan is grafted with terephthalate polyester molecular chains, so that the compatibility between the chitosan and the PET is better, and the influence on the mechanical properties of the PET material is very small. The chitosan and the grafted polyester molecular chains are also easily biodegradable, so that the PET material has a high biodegradation rate. The polyester molecular main chain grafted with the chitosan contains a large number of quaternary ammonium salt antibacterial groups, which are matched with the chitosan, so that the inhibition and killing performance and the antibacterial rate of the PET material to escherichia coli and staphylococcus aureus are significantly improved.