A kind of method for preparing cellulose solution

Abstract

The invention discloses a method for preparing a cellulose solution. The basic technical principle is to improve the wettability of the solvent to natural cellulose crystals by regulating the amphiphilic properties of the cellulose solvent, thereby promoting the dissolution of the cellulose. Based on this principle, the room temperature temperature and dissolution technology method of cellulose was proposed. The method has the advantages of simple process, dissolution at room temperature, environmental friendliness and insensitivity to the water content of the system. The cellulose solvent adopts the following composition: organic base accounts for 5-70% of the total weight of the solvent, additives account for 2-90% of the total weight of the solution, and water accounts for 1-65% of the total weight of the solvent. The cellulose is blended with the cellulose solvent to form a blend, and stirred until completely dissolved to obtain the target cellulose solution. The cellulose solution prepared by the method of the present invention is used for manufacturing regenerated cellulose film, regenerated cellulose fiber or cellulose-based composite material.

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 Akzo Nobel Company first obtained its patent for the cellulose fiber solvent spinning method, and obtained a patent for the production process in 1980; but the NMMO solvent system on the one hand Solubility is 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

Images