9 results about "Chitosan membrane" patented technology

This invention discloses a method for preparing and applying a chitosan-nanofibrillar-based smart indicator membrane loaded with anthocyanins and alizarin. The method includes the following steps: mixing beet powder with hydrochloric acid, washing with water until neutral, and drying; adding sodium hydroxide solution, mixing and reacting, washing with water until neutral, and drying; adding sodium chlorite solution, mixing, adjusting the pH to 3-3.5, reacting, and washing with water until neutral to obtain beet fiber; adding water, homogenizing under ultra-high pressure to obtain a beet nano-suspension; adding the beet nano-suspension to a chitosan-acetic acid solution and stirring, then adding glycerol; adding pigments, mixing, and obtaining a membrane solution; ultrasonically degassing, and drying to form a membrane. This membrane, as a food preservation indicator membrane, possesses both the characteristics and functions of food preservation and indicating food freshness; using beet nanofibers as a supplementary material improves the mechanical properties of the chitosan membrane; the addition of alizarin and anthocyanin mixed pigments enriches the color changes of the indicator membrane and improves its stability.

The application belongs to the technical field of bio-based packaging materials, and particularly relates to a novel double-layer composite film and application thereof. The novel double-layer composite film comprises the following steps: reacting palmitic anhydride and carboxymethyl cellulose to obtain carboxymethyl cellulose palmitate; adding a pH-sensitive natural dye indicator to obtain carboxymethyl cellulose palmitate nanoemulsion containing a pH-sensitive substance; then loading a natural polymer material to prepare a film material; finally adding the film material to the carboxymethyl cellulose palmitate to prepare a composite film, thereby obtaining the novel double-layer composite film. The double-layer composite film can be self-emulsified without adding a surfactant, and has the ability to load functional indicator (pH-sensitive color indicator) substances; meanwhile, the barrier performance of the film material, such as a chitosan film, to water vapor and oxygen is improved, and the double-layer composite film has a very promising application in food or fruit preservation. The method provided by the application is not only green in raw materials, but also uses a flow casting method, which can be applied to industrial production and has a good application prospect.

This invention discloses a topologically oriented cyclodextrin / chitosan composite membrane, its preparation method, and its applications, belonging to the field of bio-based nanomaterials technology. Using α-cyclodextrin and polyethylene glycol (PEG) as raw materials, this invention prepares topologically oriented cyclodextrin-PEG "ring-slippery" nanoparticles (TNPs). TNPs, as green and biodegradable nanoparticles, fill the chitosan network matrix, enhancing hydrogen bonding interactions with chitosan molecules and improving the mechanical properties of the chitosan membrane. This method not only uses simple raw materials and is easy to implement, but also effectively improves the mechanical strength of the chitosan composite membrane, effectively overcoming the problem of poor mechanical strength in existing chitosan composite membranes, and providing a simple and effective approach for practical production.

This invention provides a method for preparing a chitosan membrane, the chitosan membrane prepared by this method, and its applications. The method includes the following steps: S1: mixing chitosan, acid, C1-C6 monohydric alcohol, pore-forming agent, metal salt, and water to obtain a casting solution; S2: placing the casting solution on a carrier to obtain a carrier loaded with the chitosan membrane; S3: immersing the carrier loaded with the chitosan membrane sequentially in an alkaline solution and water to separate the chitosan membrane from the carrier. The chitosan membrane of this invention has a strong resistance to strong alkalis. When used as an anion exchange membrane material in fuel cells, it has advantages such as high specific power, rapid start-up, non-corrosiveness, low reaction temperature, and low oxidant requirement.

This invention relates to the field of fruit preservation technology and discloses a method for preserving mangoes containing chitosan, a eutectic solvent, and EGC. The method includes the following steps: adding chitosan to an acetic acid solution and heating and stirring in a water bath to obtain a chitosan film solution; pre-dispersing and wetting epigallocatechin in a eutectic solvent, then adding it to the aforementioned chitosan film solution and stirring at room temperature to obtain a modified chitosan composite film solution; selecting undamaged mangoes, washing and air-drying their surface moisture, immersing them in the modified chitosan composite film solution to evenly coat the surface with the film solution, removing them and air-drying them naturally, repeating the aforementioned immersion and air-drying process, and finally storing the dried mangoes in an indoor environment for preservation. This invention utilizes a eutectic solvent to solve the problem of easy aggregation of polyphenolic active substances, forming a uniform and continuous semi-permeable membrane on the mango peel, limiting moisture loss, achieving slow release of antioxidant components, and significantly extending the mango's shelf life.

The application discloses a preservative film liquid, a preservative film and a preparation method and application thereof in berry preservation, and relates to the technical field of food preservation. The preservative film liquid comprises a self-assembled nanoparticle with a melatonin core and a PEG-40 hydrogenated castor oil shell and a chitosan dispersion liquid, wherein the mass ratio of the PEG-40 hydrogenated castor oil to the melatonin is 0.25:1.2-1.6. The application also provides a preparation method of the preservative film liquid, a preservative film prepared by the preservative film liquid and application thereof in berry preservation. The application loads the melatonin in the chitosan film and overcomes the negative influence of the melatonin on the performance of the chitosan film material, so that the preservative film has good mechanical performance, barrier performance and continuous preservation function, and has important significance for the preservation of perishable foods such as berries.

The present application provides a modified oxygen-releasing nano-peroxide for degrading organic pollutants, a preparation method therefor and a use thereof, and a composite slow-release oxygen material, a preparation method therefor and a use thereof. The modified oxygen-releasing nano-peroxide comprises an oxygen-releasing nano-peroxide, a pH regulator, a polyvinyl alcohol-poly(N-isopropylacrylamide) membrane layer, and a cross-linked chitosan membrane layer. The polyvinyl alcohol-poly(N-isopropylacrylamide) membrane layer encapsulates the oxygen-releasing nano-peroxide and the pH regulator, and the cross-linked chitosan membrane layer encapsulates the polyvinyl alcohol-poly(N-isopropylacrylamide) membrane layer. The modified oxygen-releasing nano-peroxide has high purity and good dispersibility, can maintain stable dissolved oxygen content in water for a relatively long time, and has minimal impact on the environmental pH.

The application discloses a kind of based on MXene load ε-polylysine degradable photothermal antibacterial composite film and its preparation and application.The MX@PL composite nanomaterial is prepared by the electrostatic self-assembly of the successfully etched MXene and ε-PL, then glycerol plasticizer-containing chitosan film liquid is added and stirred uniformly, and the degradable packaging film with photothermal antibacterial property is prepared by solvent casting method after ultrasonic degassing.Both the shortcomings of the cationic ε-PL being easily interacted with the anion components of food matrix to hinder the antibacterial activity and the two-dimensional nanoparticles with photothermal antibacterial property are obtained.

This invention provides a method for cultivating jackfruit resistant to rust spot disease, comprising the following steps: Step 1, water and fertilizer management; Step 2, canopy shaping and pruning; Step 3, topdressing management; Step 4, rust spot disease prevention and control; Step 5, fruit management; and Step 6, harvesting and post-harvest management. In Step 1, the invention applies a specially formulated composite substrate to improve the soil ecology from the root level, inhibit soil-borne pathogens, induce plant resistance, and enhance tree health. During the critical period of disease infection, in Step 4, a protective agent composed of chitosan, horsetail fermentation liquid, and compound microbial fermentation liquid is sprayed. This agent integrates physical barriers (chitosan membrane), physiological enhancement (horsetail active silicon), and biological antagonism (beneficial microorganisms) to form a dynamic protective layer. Through multi-dimensional intervention combining symptomatic and root-cause treatment with prevention as the primary focus, the invention effectively prevents and controls the occurrence and damage of rust spot disease, achieving a long-lasting and stable control effect.