Industrial method for preparing regenerated cellulose fiber

Abstract

The invention discloses an industry method for producing regenerated cellulose silk, which is characterized in that the cellulosic dissolves in the solvent, is sufficiently stirred, for manufacturing a cellulosic solution; a regenerated cellulose silk is produced by filtering, debubbling, spinning, precipitating bath concreting, water washing, drafting and drying of the cellulosic solution; the used solvent is 6-13wt% sodium hydrate / 7-15wt% urea mixed water solution. The technique is simple, the solvent has no pollution, and the cellulosic concentrated solution contains no sulfur; the produced regenerated cellulose silk is provided with favorable mechanical properties, high color fastness, low cost, and apt to the industrial production.

Description

technical field [0001] The invention relates to an industrial method for preparing cellulose silk, which belongs to the field of natural macromolecules, and also belongs to the fields of chemistry, agriculture and environmental engineering. Background technique [0002] Plant cellulose is the most abundant renewable resource on the earth and is an environmentally friendly material. It will become one of the main chemical raw materials in the 21st century. However, cellulose is far from being fully utilized in the chemical industry at present, mainly because the cellulose dissolution process in the existing process is complicated, costly and polluting. At present, more than 90% of the regenerated cellulose products are still produced by the traditional viscose method , cellulose under the action of strong alkali (sodium hydroxide concentration 18%) and CS 2 The reaction produces cellulose xanthate, which becomes cellulose viscose. The cellulose viscose is regenerated in a d...

AI Technical Summary

Problems solved by technology

However, cellulose is far from being fully utilized in the chemical industry at present, mainly because the cellulose dissolution process in the existing process is complicated, costly and polluting. At present, more than 90% of the regenerated cellulose products are still produced by the traditional viscose method , cellulose under the action of strong alkali (sodium hydroxide concentration 18%) and CS 2 The reaction produces cellulose xanthate, which becomes cellulose viscose

The cellulose viscose is regenerated in a dilute acid solution after casting to obtain cellulose filaments; this process releases a large amount of toxic H during the production process 2 S and CS 2 Gas, not only damages human health, but also seriously pollutes the environment

There are problems of environmental pollution and solution recovery in the production of cupro man-made fiber by cupro method

Other organic or inorganic new solvents, such as: dimethyl sulfoxide-nitrogen oxide, aqueous solution, Ca(SCN) 2 and aqueous NaSCN, ZnCl 2 Aqueous solution, chloral-dimethyl sulfoxide-pyridine mixture, LiCl / DMAc are difficult to industrialize due to various reasons

In recent years, a new solvent N-methylmorpholine oxide (NMMO) has emerged and is recognized as the most promising cellulose solvent. The classification of cellulose fibers produced by this method is named "Lyocell", and it is used internationally to prepare A small amount of cellulose fiber products have entered the market, but due to its high price and high spinning temperature, the development of industrial production is slow

6% NaOH / 5% thiourea aqueous solution has been used as a new cellulose solvent to dissolve cellulose and successfully prepare regenerated cellulose filaments with excellent strength (Chinese patent: ZL00128162.3), but the solvent system must be kept under freezing conditions for 3 - It takes 5 hours to dissolve cellulose to prepare a transparent concentrated cellulose solution, so it is difficult to realize industrialization