Method for preparing cellulose solution

Abstract

The invention discloses a method for preparing a cellulose solution.According to the basic technical principle of the method, the wetting property of a solvent on natural cellulose crystals is improved with the amphipathicity of the cellulose solvent so that dissolution of cellulose can be promoted.Based on the principle, the invention provides a room-temperature mild dissolution technical method for cellulose.The method has the advantages that the technology is simple, room-temperature dissolution is achieved, and the method is environmentally friendly and not sensitive to the moisture content of a system.The cellulose solvent is prepared from, by weight, 5-70% of organic base, 2-90% of an assistant and 1-65% of water.Cellulose and the cellulose solvent are blended to form a blend, stirring is carried out until complete dissolution, and the target cellulose solution is obtained.The cellulose solution prepared with the method is used for manufacturing regenerated cellulose membranes or regenerated cellulose fibers or cellulose-base composites.

Description

technical field [0001] The invention relates to the technical field of cellulose solvents, in particular to a cellulose solvent and a method for preparing a cellulose solution with it. Background technique [0002] Cellulose is the most abundant natural biopolymer in nature, which is widely distributed in the world and has a variety of sources. Humans can extract unmodified natural cellulose from the secretions of plants (such as trees, cotton, bamboo or crop straw, etc.) or bacteria. Cellulose has many excellent properties such as renewability, biodegradability, biocompatibility and derivatization. Therefore, various products based on cellulose have been widely used in the modern society with highly developed technology, especially in the fields of textile, papermaking, coating, packaging, composite materials, medical treatment, sanitation and environmental engineering. As a renewable raw material, cellulose and its various derivatives can also replace many chemicals deri...

AI Technical Summary

Problems solved by technology

Among them, NMMO is considered to be a very promising cellulose solvent. In 1978, the German AkzoNobel company first obtained its cellulose fiber solvent spinning patent, and obtained a production process patent in 1980; Affected by water content (including solvent, sample and environment, etc.), on the other hand, there are problems such as high dissolution temperature and side reactions, so it has extremely high technical threshold and high production cost

As a green chemical solvent that has emerged in recent years, ionic liquid is also a hot spot in the research of cellulose solvents. It has good cellulose solubility and solvent recyclability; but it has the disadvantages of high solution viscosity and high dissolution temperature. And because a small amount of water will seriously affect its solubility, it is not conducive to large-scale industrialization

Solvents such as NaOH / thiourea are an aqueous solvent system, and the cost of raw materials is relatively low, which is a relatively economical solvent system; however, due to the need for low temperature (-12°C) operation, and its solubility to cellulose is limited The concentration of cellulose, the degree of polymerization, and energy consumption are affected by many factors, which is not conducive to its industrialization

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