2482 results about "Nanocellulose" patented technology

The invention discloses a microencapsulation repairing agent and an intelligent self-repairing ultrahigh-strength ultrahigh-toughness cement-based structural material, the microencapsulation repairing agent is mainly composed of a humidity-responsive outer layer, a pH-responsive middle layer and a temperature-responsive inner layer, and the outer layer is modified with a silane coupling agent. The intelligent self-repairing ultrahigh-strength ultrahigh-toughness cement-based structural material is mainly prepared from the microencapsulated repairing agent, nano carbon black, nano montmorillonite, nano cellulose and other raw materials. According to the invention, by introducing the self-repairing microcapsule with a specific structure and materials such as nano carbon black, nano montmorillonite and nano cellulose, the strength, toughness and durability of the concrete are remarkably improved, and the concrete has an intelligent self-repairing function.

The invention provides anti-cracking and anti-seepage high-performance concrete, which relates to the technical field of concrete and comprises Portland cement, aggregate, a high-activity mineral admixture, a calcium-magnesium composite expanding agent, nano silicon dioxide particles, a microcapsule-packaged sodium silicate and calcium lactate solution, paraffin / expanded graphite composite phase change microspheres, steel fibers, PVA fibers and nano cellulose. The self-repairing concrete has the characteristics that the anti-cracking performance is comprehensively improved, the anti-seepage grade is broken through, the self-repairing capability is long-acting, the construction adaptability is enhanced, and the like.

The invention provides a high-temperature-resistant and high-salt-resistant nano imbibition agent as well as a preparation method and application thereof. The high-temperature-resistant and high-salt-resistant nano imbibition agent is prepared from amination modified mesoporous silica nanoparticles, nano cellulose, rhamnolipid, an anionic surfactant, citrate modified sodium zirconium phosphate, polyethylene glycol-b-polycaprolactone and a sulfydryl-carboxyl imidazoline derivative, therefore, the composite carrier formed by the aminated mesoporous silica nanoparticles and the nanocellulose has high mechanical strength and uniform dispersity, the oil-water interfacial tension is reduced through the synergistic effect of the rhamnolipid and the anionic surfactant, and the crude oil stripping efficiency is remarkably improved; the citrate modified sodium zirconium phosphate enables the salt resistance of the system to be greatly improved, and in a high-temperature and high-salt oil reservoir environment, the nano imbibition agent can remarkably improve the crude oil recovery rate and reduce the injection pressure and dosage; meanwhile, good adsorption resistance is achieved, and reservoir blockage is prevented; in addition, low-toxicity corrosion inhibition components protect equipment, and the service life of an oil well is prolonged.

The invention relates to the field of membrane materials, and discloses an epoxy modified starch-based degradable membrane and a preparation method thereof, the epoxy modified starch-based degradable membrane comprises epoxidized starch, modified nanocellulose and a plasticizer; the modified nano cellulose is prepared by mixing a modified composite filler, a nano cellulose dispersion liquid and a zinc acetate dihydrate aqueous solution; the nano-cellulose dispersion liquid is prepared by adhering polytannic acid formed by oxidation and self-polymerization of tannic acid to the surface of nano-cellulose; the modified composite filler is prepared by performing carboxylation modification on nano titanium dioxide coated fumed silica nanoparticles by using succinic anhydride and gamma-aminopropyltriethoxysilane, then reacting with polyethyleneimine to obtain an aminated composite filler, and finally grafting glycidyl dodecyl dimethyl ammonium chloride to the surface of the aminated composite filler. The prepared film material is high in tensile strength, has certain hydrophobicity, and has good heat resistance, antibacterial property and flame retardant property.

The invention discloses bone cement for orthopedic repair and a preparation method thereof, and relates to the technical field of bone cement. The bone cement for orthopedic repair comprises solid-phase powder and a liquid-phase component, the solid-phase powder comprises the following components in parts by weight: 55-65 parts of composite calcium phosphate, 10-15 parts of bioactive glass, 2-3 parts of a developing agent, 1-2 parts of hydroxyapatite, 8-12 parts of a modified toughening agent and 2-3 parts of nano cellulose fibers; the liquid phase component is prepared from the following components in parts by weight: 40 to 50 parts of a sodium alginate solution, 10 to 20 parts of methacrylated gelatin, 0.5 to 1 part of transglutaminase, 30 to 60 parts of a citric acid buffer solution and 1 to 2 parts of an antibacterial agent. The preparation method comprises the following steps: reacting pentaerythritol with 12-oxododecanoic acid to obtain an intermediate 1, and reacting the intermediate 1 with dopamine to prepare the modified toughening agent. The bone cement for orthopedic repair prepared by the invention has good mechanical, self-repairing and antibacterial properties.

The invention relates to the technical field of biological induction of calcium carbonate deposition, in particular to self-repairing concrete for biological induction of calcium carbonate deposition and a preparation method thereof. The cement comprises the following components in parts by weight: 320-380 parts of Portland cement and the like. The biomineralization composite inducer contains a genetically engineered bacterium solution, a urea-calcium chloride solution and a nano strontium carbonate seed crystal; the nano silicon dioxide-graphene composite powder is prepared by chemical vapor deposition; the wall material of the double-response microcapsule contains a temperature-sensitive polymer, and the core material contains a plurality of components; nanocellulose whiskers are also added; self-repairing is achieved through cooperation of multiple components, and all the components are specially treated or prepared. The self-repairing concrete is high in self-repairing efficiency, and wide cracks can be repaired; the mechanical property is excellent, and the compression strength and the breaking strength are remarkably improved; working performance is good, and construction is convenient; durability is good, and erosion and permeability are resisted; environmental protection and economy are considered, and the application prospect is wide.

The invention discloses a multifunctional electronic product screen protective film and a preparation method thereof. The protective film comprises a modified base film and a multifunctional composite layer compounded on the surface of the modified base film, the multifunctional composite layer comprises an elastic buffer layer and a self-repairing layer which are sequentially arranged from inside to outside; wherein the elastic buffer layer is an elastic buffer layer with gradient density; the elastic buffer layer comprises the following components in parts by weight: 100 parts of a thermoplastic polyurethane elastomer, 15-25 parts of hollow glass microspheres, 10-15 parts of polyethylene glycol and 3-6 parts of an isocyanate cross-linking agent; the self-repairing layer comprises the following components in parts by weight: 100 parts of a dynamic reversible covalent bond polymer, 30-40 parts of phase change material microcapsules, 10-15 parts of nano cellulose, 5-8 parts of a near-infrared photosensitive initiator and 2-4 parts of an antioxidant. Compared with the prior art, the protective film provided by the invention has excellent scratch self-repairing performance, good adhesion and high anti-explosion screen performance.

The invention relates to the technical field of film material preparation, and discloses a polylactic acid antibacterial packaging film and a preparation method thereof, the polylactic acid antibacterial packaging film comprises the following raw material components by weight: 60-80 parts of polylactic acid, 10-20 parts of polyvinyl alcohol, 10-20 parts of nano zinc oxide, 0.5-1.5 parts of nano cellulose, 1-3 parts of an antibacterial agent, and 10-15 parts of corn starch; the antibacterial agent is prepared from the following components in parts by weight: 5-10 parts of carboxymethylated chitosan and 0.5-2 parts of a dynamic disulfide bond cross-linking agent, the substitution degree of the carboxymethylated chitosan is greater than or equal to 80%, the antibacterial agent is prepared from tea tree essential oil and eugenol, and the dynamic disulfide bond cross-linking agent is bis (3-aminopropyl) disulfide. By adopting a composite system of carboxymethylated chitosan and a dynamic disulfide bond cross-linking agent, the technical effects of humidity-triggered self-repairing and mechanical property synergistic improvement are achieved, and compared with a packaging film with a single polymer base material in the prior art, the problem of antibacterial failure caused by mechanical damage is solved.

The invention relates to the technical field of thermal management material preparation, solves the technical problems of loose heat conduction network structure and non-uniform heat conduction direction of a flexible composite phase change material, and particularly relates to a magnetic polymer-based flexible composite phase change material and a preparation method thereof. Comprising the following steps: preparing a modified polydimethylsiloxane prepolymer from a carbon nanotube dispersion liquid and a polydimethylsiloxane prepolymer; adopting a Pickering emulsion method to mix 42 # paraffin, the modified polydimethylsiloxane prepolymer and nano cellulose to prepare a composite phase change material emulsion; silver mirror reaction is adopted to carry out surface silver plating on the magnetic neodymium iron boron particles; the magnetic polymer-based flexible composite phase change material is prepared from the composite phase change material emulsion and the surface-silvered magnetic neodymium iron boron particles. The high flexibility and magnetism of the prepared material in a normal temperature state endow the material with a more convenient installation mode and lower contact thermal resistance, the heat conduction network structure and component compatibility of the material are improved, and the application requirements of a phase change thermal management technology can be met.

The invention relates to the technical field of high-barrier composite packaging films, and discloses a high-barrier composite packaging film with an antibacterial function, which sequentially comprises a base layer, a nano composite barrier layer, an antibacterial functional layer and an outer protective layer from bottom to top, and the layers are tightly attached through a coated starch-based adhesive. According to the high-barrier composite packaging film with the antibacterial function, the cellulose nanowhiskers have the characteristics of high strength and high modulus and are mixed with the bio-based polylactic acid, so that the tensile strength and tear resistance of the bio-based polylactic acid can be remarkably improved, and the structural stability of the packaging film in the using process is guaranteed; nano titanium dioxide and nano cellulose aerogel are arranged in the nano composite barrier layer, so that the barrier property of the packaging film on oxygen and ultraviolet rays can be enhanced, and the packaging film also has a certain antibacterial effect; in addition, the nanocellulose aerogel has a loose porous structure, so that gas molecules can be effectively prevented from passing through, and the barrier property is further improved.

The invention provides anti-disturbance micro-expansion lightweight ultra-high performance concrete and a preparation method thereof. According to the concrete disclosed by the invention, the generation of micro cracks under disturbance can be effectively inhibited through the fiber bridging effect of the crystal whiskers and the temperature-shrinkage indented fibers and the micro pre-compressive stress of the temperature-shrinkage indented fibers under hydration exothermic excitation; the micro-crack healing effect of the nano-cellulose and the internal curing effect of the saturated pre-wetted coal gangue ceramsite cooperate to repair microstructure damage generated under strong disturbance, and the disturbance resistance of the concrete is further improved. The internal curing effect of the saturated pre-wetted coal gangue ceramsite and the expansion agent shrinkage compensation synergistically improve the volume stability of the concrete. The 28d compressive strength of the concrete is gt; compared with common ultra-high performance concrete, the volume weight of the ultra-high performance concrete is reduced by more than 20%, the anti-disturbance strength retention rate of the ultra-high performance concrete is greater than or equal to 95%, the ultra-high performance concrete shows excellent bonding and durability, the comprehensive performance of the ultra-high performance concrete is greatly improved, and the ultra-high performance concrete has important practical application value.

The invention belongs to the field of electrochemistry, and discloses a silicon-carbon negative electrode material based on nanocellulose and a preparation method and application thereof. The preparation method comprises the following steps: dispersing cellulose in deionized water, and carrying out physical stripping and ionic liquid assisted acidolysis to obtain a cellulose colloidal solution; and dispersing the conductive agent and the carbon source into the colloidal solution, adding the coupling agent and the silicon source, and carrying out spray drying and sintering. According to the invention, nano cellulose preparation and silicon carbon preparation processes are combined, so that an intermediate separation process is reduced, and the process is simplified. Meanwhile, in the silicon-carbon balling process, the ionic liquid and the coupling agent in the slurry can induce and promote surface combination of the carbon source and the silicon source; the nano cellulose promotes nano-micro forming of components such as silicon and carbon, and is coupled with the conductive agent in the carbonization process to form an internal conductive network and a coating layer; in the carbonization process, hydrolysis catalyst metal ions play a role in catalyzing gas source cracking deposition to form a stable coating carbon layer. The silicon-carbon material is novel in route, rapid electron transmission and capacity exertion are guaranteed through the conducting layers from inside to outside, and the cycling stability of the material can be improved through the multi-carbon-layer coating structure.

The invention relates to the field of sponge materials, and provides an antibacterial degradable sponge material and a preparation method thereof. The material is prepared from protocatechuic acid modified quaternized chitosan, quaternary ammonium salt grafted gelatin, sodium alginate, polyhydroxybutyrate, polycaprolactone, a polylactic acid-glycolic acid copolymer, hexamethylene diisocyanate, a foaming agent, nano cellulose, vitamin E, polyethylene glycol, triethylamine and dimethylformamide. Protocatechuic acid and quaternized chitosan are subjected to amidation modification, and chitosan and gelatin are subjected to quaternization treatment by adopting 2, 3-epoxypropyl trimethyl ammonium chloride, so that the antibacterial property and biodegradability of the material are improved. In the material preparation process, through vacuum degassing, foaming vacuum degree and humidity control and a multi-step drying process, it is ensured that the average pore size of the material is uniform (50-200 microns) and the porosity is high (50%-90%), and the obtained material has excellent antibacterial property and degradability and has wide application value.

The invention discloses a high-strength nano composite stiffening filling master batch and a preparation method thereof, and relates to the technical field of high polymer materials, the raw materials comprise a nano filler, a matrix material and a functional additive; the nano filler comprises nano diamond, nano silicon carbide and bio-based nano cellulose, the base material comprises polyimide, polyether-ether-ketone and bio-based polylactic acid, and the functional additive comprises a hindered phenol antioxidant, a nano aluminum hydroxide flame retardant, a nano silicon dioxide reinforcing agent, an ultraviolet light absorber, a carbon nano tube and nano silver particles. Nano-diamond, nano-silicon carbide and bio-based nano-cellulose are adopted as nano-fillers, polyimide, polyether-ether-ketone and bio-based polylactic acid are combined as base materials, and a plurality of functional additives are added, so that the preparation of the high-strength nano-composite stiffening filling master batch is realized; and the problems of poor dispersibility, mechanical property damage, insufficient hardness and poor interface bonding of the traditional filler master batch can be solved.

The invention discloses a label cleaning type crispness increasing method for fried food, and belongs to the field of fried products. According to the preparation method, firstly, lentinus edodes stem nanocellulose is prepared by combining enzymolysis with a high-pressure homogenization method, and the lentinus edodes stem nanocellulose is compounded with casein, so that stable lentinus edodes stem nanocellulose-casein gel emulsion can be prepared; then the gel-like emulsion is applied to the paste-coated fried product, and the gel-like emulsion is used for forming pores in advance in the paste so as to achieve the crispness increasing effect, reduce the oil content and inhibit grease oxidation. The stable gel emulsion based on a natural formula can replace a commercial leavening agent to realize clean label type crispness enhancement, and the prepared paste can be applied to various paste fried foods and has a good market prospect.

The invention relates to the technical field of papermaking, and particularly provides high-strength tipping base paper for cigarettes and a preparation process of the high-strength tipping base paper. The tipping paper base paper for the cigarettes comprises a fiber raw material; functionalizing the nano cellulose; a cellulase; a dry strength agent; a wet strength agent; and a sizing agent. Nano cellulose is functionalized and a synergistic stepped enhancement mechanism is constructed, so that the synergistic breakthrough of the high-strength raw tipping paper for cigarettes in the aspects of strength, wet strength and air permeability is realized; after the functionalized nanocellulose is subjected to carboxylation treatment, the hydrogen bond and electrostatic adsorption between the functionalized nanocellulose and the fiber are enhanced, and the bonding strength in a dry state and a wet state is remarkably improved; meanwhile, the wet strength agent is added in stages, and the adsorption sequence of the dry strength agent is optimized, so that the reinforcing agent constructs a stable three-dimensional network framework in the paper sheet, and the end breaking risk under high-speed winding is effectively reduced.

The invention relates to the technical field of material science and engineering, and discloses a nanocellulose-based oil-water separation and adsorption composite material, which is prepared from the following raw materials in parts by mass: 35 to 45 parts of nanocellulose; 8 to 11 parts of bagasse cellulose; 10 to 15 parts of sodium lignin sulfonate; 4 to 8 parts of chitosan; 5-10 parts of oxidized starch; 5 to 8 parts of cellulose nanowhiskers; 2-5 parts of silicon dioxide nanoparticles; 0.5 to 1 part of calcium carbonate nanoparticles; 1-2 parts of a citric acid cross-linking agent; 1-2 parts of graphene oxide; 0.3 to 0.6 part of ethylene diamine tetraacetic acid; 2-5 parts of glycerol; 0.4 to 1 part of stearoyl chloride; 2-4 parts of nano iron oxide; the preparation method comprises the following steps: pretreating the raw materials, mixing the pretreated raw materials into slurry, carrying out crosslinking and ultrasonic dispersion, standing to obtain a basic mixture, injecting the basic mixture into a mold, carrying out freeze drying to form a photocatalytic layer, carrying out centrifugal dewatering, carrying out chelation reaction, spraying a composite solution, and carrying out vacuum drying to obtain the photocatalytic material. The obtained composite material has the advantages of efficient adsorption capacity, good mechanical properties, environmental friendliness, degradability and low preparation cost.

The invention relates to the technical field of composite materials, in particular to a heat and sound insulation PVB intermediate film and a preparation method thereof. The problem that a PVB intermediate film is insufficient in heat insulation and aging resistance is solved. The preparation method comprises the following steps: pre-plasticizing PVB resin, shearing and mixing the pre-plasticized PVB resin and silane coupling agent modified enhanced nano cellulose, sequentially adding additives such as a plasticizer, molybdenum trioxide loaded lanthanum hexaboride, a composite light stabilizer and modified cerium oxide, and carrying out tape casting and hot pressing treatment to obtain the PVB intermediate film. Wherein the modified lanthanum hexaboride enhances infrared ray shielding, the composite light stabilizer and the modified cerium oxide synergistically improve the aging resistance, all the components are subjected to substance cooperation and process cooperation, comprehensive improvement of heat insulation, sound insulation and aging resistance of the PVB intermediate film is achieved, and the PVB intermediate film is suitable for the field of high-strength building glass.

The invention relates to a polyethylene and silica gel mixed material, a preparation method thereof and application of the polyethylene and silica gel mixed material in a composite optical cable silicon core tube. The composite material comprises the following components in parts by weight: high-density polyethylene, an ethylene-siloxane copolymer elastomer, a maleic anhydride grafted polyolefin elastomer, hydroxylated nano silicon dioxide, liquid paraffin, a crystallization nucleating agent, an ultraviolet light absorber, an auxiliary stabilizer, a processing aid and color master batch. The liquid paraffin is formed by blending dual-molecular-weight paraffin with different carbon chain lengths, and part of the liquid paraffin is grafted and modified by polybutylene so as to enhance the anchoring capacity of the lubricating phase; in addition, nano cellulose crystals grafted by a PEG-PCL (Polyethylene Glycol-Polycaprolactone) block copolymer are introduced, so that the dimensional stability and the interface structure integrity of the material are synergistically enhanced. The composite material has excellent low friction, thermal oxidation stability, creep resistance and ultraviolet aging resistance, and is suitable for preparation of a high-performance composite optical cable silicon core tube.

This invention belongs to the field of marine antifouling, and specifically relates to a transparent, self-lubricating organosilicon hybrid antifouling coating with a negatively charged surface and its preparation method. The antifouling coating is obtained by a sol-gel reaction of modified nanocellulose, hydroxy acid, and functional fluorine / siloxane monomers; the mass ratio of the hydroxy acid to the modified nanocellulose is 10–100:1; the mass ratio of the functional fluorine / siloxane monomer to the modified nanocellulose is 10–300:1. This invention, based on a multi-element green antifouling strategy, constructs a material surface with negative charge, self-lubrication, and low surface energy. The prepared antifouling coating exhibits excellent transparency, mechanical properties, and static antifouling performance. This antifouling coating is environmentally friendly and has broad application prospects in the field of marine antifouling.

The present invention discloses a pH-responsive pesticide slow-release hydrogel sphere and a preparation method thereof, belonging to the technical field of slow-release pesticides. The present invention uses carboxylated nanocrystalline cellulose modified by polyethyleneimine as a raw material, which is self-assembled with modified montmorillonite through electrostatic binding, and then loaded with pesticides in an organic solvent. Then, sodium alginate is used as a coating material and anhydrous calcium chloride is used as a cross-linking agent to prepare a pH-responsive pesticide slow-release hydrogel sphere of nanocrystalline cellulose composite montmorillonite by dropping, which is used for the slow release of pesticides in the soil environment. Under the optimal conditions, the encapsulation rate of fipronil in the organic solvent by the hydrogel sphere of the present invention is above 64.1 wt%, and the loading rate is above 67.3 wt%. In the soil environment with different pH values, the highest release rate of pesticides after 120 h is above 59.7%, and the pesticide release rate increases with the increase of pH until the hydrogel skeleton completely breaks, and the purpose of adjusting the pesticide release rate can be achieved by adjusting the pH.

The invention provides a preparation method of an environment-friendly high-performance gas barrier film, which is characterized in that a solution blending method is adopted to prepare a polyvinyl alcohol / nanocellulose / covalent organic framework nanosheet ternary composite system, and a coating method is adopted to prepare the high-performance gas barrier film under high-temperature evaporation. Multidimensional mixed nanocellulose and covalent organic framework nanosheets are introduced as functional fillers to form a stable intercalation structure with a polyvinyl alcohol matrix, so that the interfacial compatibility of the components is remarkably improved. The multi-component gas barrier film is endowed with high humidity resistance, chemical stability, high gas barrier property and the like by regulating and controlling the heat treatment temperature, the environment-friendly gas barrier film material shows good application prospects in the fields of chemical protective clothing and the like, and a new thought is provided for development of high-performance protective materials.

The invention discloses a clean label type crispness increasing method for small crispy meat, and belongs to the field of fried products. The preparation method comprises the following steps: firstly, efficiently preparing a lentinus edodes stem nanocellulose-soybean protein isolate compound by combining enzymolysis with a high-pressure homogenization method, preparing a gel-like emulsion with 50-70% of an oil phase by taking the lentinus edodes stem nanocellulose-soybean protein isolate compound as a dispersion phase, and then adding the gel-like emulsion as a pore-forming agent into paste, so as to develop a new way for increasing the crispness of the fried small crisp meat. The lentinus edodes stem nanocellulose-soybean protein isolate gel emulsion is applied to the small crispy meat, the crispness of the small crispy meat can be increased, the oil content and the oil oxidation degree of the small crispy meat can be reduced, the color and luster of the small crispy meat can be effectively regulated and controlled, and technical innovation and quality improvement in the field of fried foods are expected to be promoted.

The invention discloses an amphiphilic chitosan and plant nanocellulose composite coating fresh-keeping material, which is prepared from the following ingredients in percentage by mass: 0.5 to 20 percent of amphiphilic chitosan, 0.1 to 5.0 percent of plant nanocellulose, 0.5 to 10.0 percent of coalescing agents, 0.1 to 3.0 percent of antioxidants and the balance deionized water. Wherein the amphiphilic chitosan is prepared from chitosan, quaternary phosphonium salt and sorbic acid. Amphipathic chitosan of the material has hydrophilic groups such as amino and carboxyl and a sorbate hydrophobic group, has hydrophilicity and hydrophobicity at the same time, and is extremely easy to combine with substances such as a coalescing agent, plant nanocellulose and an antioxidant to form a stable polymeric membrane layer, so that the mechanical property after membrane formation is remarkably improved, and the material has a good application prospect. Meanwhile, the plant nanocellulose particles can be stably coated in the polymeric membrane material layer, so that the mechanical property of the material is enhanced, and lasting and efficient antibacterial and antioxidant effects are realized. The invention further discloses a preparation method and application of the amphiphilic chitosan and plant nanocellulose composite coating fresh-keeping material.

The invention discloses a skin-friendly antibacterial spinning yarn and a preparation method thereof, and relates to the field of spinning yarns. When the skin-friendly antibacterial spinning yarn is prepared, 3-amino-1, 2, 4-triazine and vinyl phosphonyl chloride are subjected to a reaction, and a phosphorus-nitrogen flame-retardant monomer is obtained; activating bamboo nano-cellulose with ammonium ceric nitrate, grafting a phosphorus-nitrogen flame-retardant monomer, and performing electrostatic spinning to obtain modified bamboo nano-cellulose coated fibers; dipping polyester filament yarns in dopamine hydrochloride and sodium hypochlorite in sequence to obtain modified polyester core yarns; the modified bamboo nano-cellulose wrapping fiber and the modified polyester core yarn are twisted through a ring spinning frame and then react with 3, 3 ', 4, 4'-benzophenone tetracarboxylic dianhydride, and the skin-friendly antibacterial spinning yarn is obtained. The skin-friendly antibacterial spinning yarn prepared by the method has excellent skin-friendly antibacterial property, flame retardance, aging resistance and mechanical property.

The invention relates to the technical field of packaging, and discloses an express waterproof bag and a preparation method thereof, the express waterproof bag comprises the following components by mass: 60-70 parts of polylactic acid, 20-30 parts of poly (adipic acid-butylene terephthalate), 5-10 parts of polyhydroxyalkanoate, 2-5 parts of nano cellulose, 1-3 parts of modified montmorillonite, 0.5-1.5 parts of a photosensitizer, 0.25-0.5 part of a bio-enzyme catalyst, and 0.5-1 part of a plasticizer. By combining polylactic acid, poly (butylene adipate-co-terephthalate) and polyhydroxyalkanoate (PHA), the biodegradability is remarkably improved while the mechanical strength of the waterproof bag is maintained, PLA is degraded into carbon dioxide and water through hydrolysis reaction, the degradation rate of PLA is adjusted through PBAT and PHA, premature degradation is avoided, rapid degradation after use is ensured, and the waterproof bag has the advantages of being environmentally friendly and free of pollution. Furthermore, the degradation rate is optimized, the stability and environmental friendliness of the material are balanced, and plastic pollution is avoided.

The invention relates to a whitening and freckle-removing composition containing a composite plant extract and a preparation method of the whitening and freckle-removing composition, and belongs to the technical field of cosmetics. The composition disclosed by the invention is prepared from the following raw materials in parts by weight: 5 to 8 parts of pineapple leaf nano cellulose, 10 to 16 parts of modified starch, 10 to 15 parts of longan seed extract, 6 to 10 parts of mulberry bark extract, 5 to 8 parts of nicotinamide and 8 to 10 parts of hyaluronic acid. The pineapple leaf nanocellulose contains flavonoid and phenolic compounds with double-bond, conjugated double-bond and triple-bond structures, and modified starch is used as a filler to form a film on the surface of skin, so that an anti-ultraviolet protection wall is formed; the betaine-malate ionic liquid is added into the longan seeds, so that extraction of polyphenol in the longan seeds is improved, the longan seeds have acid-base buffering capacity, an auxiliary does not need to be added to adjust the pH value, the components of the prepared composition interact, and the whitening and freckle removing effects are achieved from multiple aspects of ultraviolet resistance, oxidation resistance, inflammation resistance and skin metabolism improvement.

The invention discloses a corn straw nanocellulose reinforced water-resistant fully-degradable mulching film and a preparation method thereof, and belongs to the technical field of agricultural mulching films. The method comprises the following steps: performing two-step DES treatment on corn straws to obtain a nano-cellulose dispersion liquid; a PVA solution with the concentration of 8-12 wt% is prepared; 1-3 wt% of an ultrasonic dispersion silicon source dispersion liquid is prepared; the preparation method comprises the following steps: adding 10 parts of PVA solution, 1.25 parts of silicon source dispersion liquid and 20 parts of glycerol into 100 parts of nanocellulose dispersion liquid to obtain film coating liquid, carrying out curtain coating in a polytetrafluoroethylene mold, and naturally drying to form the film. PVA has good film-forming property but poorer water resistance, and nano cellulose and nano silicon dioxide can be used as green modifiers to be blended with PVA and self-assembled to form a hydrogen bond cross-linking system, so that a'rigid cellulose and silicon dioxide network-flexible PVA matrix 'enhanced structure is formed. Meanwhile, forestry and agricultural residues (corn straw) are adopted as raw materials, nanocellulose is prepared through a two-step deep eutectic solvent (DES), and the problem of high pollution caused by traditional strong acid / strong alkali treatment is solved.

The invention provides loofah sponge nanocellulose hydrogel and a preparation method thereof.The preparation method comprises the following steps that anhydrous citric acid, choline chloride and water are mixed to react, and a ternary eutectic solvent is obtained; dispersing loofah sponge purified cellulose in a ternary eutectic solvent, washing and filtering a product to be neutral, dispersing the product in water, and performing ultrasonic treatment to obtain loofah sponge nanocellulose turbid liquid; dissolving sodium lignin sulfonate and lithium chloride in a sodium hydroxide solution to obtain a precursor solution; mixing the loofah sponge nanocellulose suspension with water, polyacrylamide, ammonium persulfate and N, N-methylene bisacrylamide, pouring the precursor solution into the loofah sponge nanocellulose suspension, uniformly stirring the mixture, pouring the mixture into a mold, and sealing the mold; and forming to obtain the loofah sponge nanocellulose hydrogel. The invention also provides an application of the hydrogel. The hydrogel disclosed by the invention has excellent biocompatibility, mechanical property and conductivity, has a wide application prospect in the field of flexible electronics, and is simple in preparation process, low in cost, green and environment-friendly.

The invention provides a preparation method of a self-repairing waterborne polyurethane coating based on a synergistic effect of a dynamic disulfide bond and a pH response microcapsule. The preparation method comprises the following steps: step 1, preparing a dynamic disulfide bond-containing waterborne polyurethane (D-WPU) emulsion; step 2, preparing a pH response microcapsule; step 3, preparing a self-repairing waterborne polyurethane coating; a dynamic disulfide bond of the self-repairing waterborne polyurethane coating rapidly repairs macrocracks at 50-60 DEG C through mercaptan catalysis, and pH < lt > is caused by local corrosion of a pH response microcapsule; when the pH value is 4.0, cysteine is released, sulfydryl accelerates recombination of dynamic bonds, and amino enhances cohesive force of the coating and neutralizes H < + >. And in combination with a hydrogen bond network of the nanocellulose, the coating has low-temperature repair (the mechanical strength recovery rate is greater than or equal to 90%), high toughness (the water absorption rate is less than or equal to 2.1%) and long-acting corrosion resistance (the salt spray resistance life is greater than or equal to 600 hours), and is suitable for severe environments such as ocean engineering and new energy equipment.