Nanocellulose film with adjustable hydrophilicity and hydrophobicity, and preparation method and application thereof

Abstract

The invention provides a nanocellulose film with adjustable hydrophilicity and hydrophobicity, and further provides a preparation method and an application of the nano cellulose film. The nanocellulose film is prepared from nanocellulose, a polymer, a sizing agent and a sizing accelerant. The nanocellulose film with adjustable hydrophilicity and hydrophobicity has the advantages of high hydrophobic contact angle, high water and oxygen blocking capacity, good stability and good printability. Infrared secondary heating and sizing agent addition are adopted, so the sizing degree of the nanocellulose film is improved. The preparation method of the film has the advantages of simplicity, easiness in implementation, convenience in operation, and short preparation period; and an industrially mature tape casting process is adopted, so the nanocellulose film with adjustable hydrophilicity and hydrophobicity can be produced on a large scale.

Description

technical field [0001] The invention belongs to the field of material science, and in particular relates to an adjustable hydrophilic and hydrophobic nano-cellulose film, its preparation method and application. Background technique [0002] Cellophane, as a commercial regenerated cellulose film that can replace polypropylene and polyethylene, has been widely used in food packaging, printing paper, inner liner and decorative packaging. In the production process of cellophane, sulfogen acidification will use a large amount of carbon disulfide, and a large amount of carbon disulfide will be produced when it is solidified in the acid bath. There are a series of by-products, such as hydrogen sulfide, sulfur dioxide and sulfuric acid mist. The process is expensive and there is secondary pollution, so in recent decades, the global production of cellophane has been hovering around 100,000 tons per year, and the potential market demand is very huge. It is very necessary to develop l...

AI Technical Summary

Problems solved by technology

The existing technology also utilizes a series of operations such as organoalkoxysilane, water-based fluorocarbon resin and corresponding curing agent to obtain modified nanocellulose, and obtains a hydrophobic nanocellulose film by vacuum filtration, but the operation is complicated. long cycle

The prior art prepares hydrophobic substances containing organoalkoxysilanes, and then prepares superhydrophobic and oleophobic transparent nanocellulose paper by means of suction filtration-hot pressing. The key step is still the preparation of hydrophobic substances, but only through Simple mixing adds hydrophobic substances to the cellulose dispersion, its long-term stability needs to be further determined, and there are certain limitations in large-scale production

In the prior art, a water-resistant regenerated nano-cellulose film can be prepared by combining mechanical and chemical methods. By spraying the ethanol solution of polymethyltriethoxysilane on the surface, the hydrophobic modification of the cellulose film can be realized. However, it only involves surface hydrophobization modification, and the stability of the hydrophobic coating needs to be further improved.

[0006] Although the existing chemical modification can realize the regulation of the hydrophobicity of the nanocellulose membrane, there are usually disadvantages such as long reaction time, need for heating and catalyst, low efficiency and difficulty in large-scale production, and there is a long distance from industrial production.