A kind of preparation method of improving the free fiber silk of sodium carboxymethyl cellulose aqueous solution

Abstract

The invention relates to a preparation method of sodium carboxymethyl cellulose, aiming at providing a preparation method of the sodium carboxymethyl cellulose for improving a free fiber yarn contained in a water solution. The preparation method for improving the free fiber yarn contained in a sodium carboxymethyl cellulose water solution comprises the following steps: respectively crushing purified cotton and wood pulp, and successively adding the crushed purified cotton and wood pulp to a kneader with a sodium hydroxide water solution and an ethanol water solution together; vacuumizing the kneader, filling an inert gas, and carrying out alkalization reaction at constant temperature of 38-50 DEG C for 40-120 minutes; adding an etherifying agent, increasing temperature to 75-80 DEG C, and carrying out etherifying reaction at constant temperature of 75-80 DEG C for 30-90 minutes; and washing, neutralizing, centrifugalizing, drying and crushing a reaction product to obtain a sodium carboxymethyl cellulose finished product. According to the sodium carboxymethyl cellulose prepared through the method disclosed by the invention, the sodium carboxymethyl cellulose water solution is clear and transparent and contains no free fiber yarn so as to be applied to the industrial field with strict requirements on the free fiber yarns.

Description

technical field [0001] The invention relates to a preparation method of sodium carboxymethylcellulose, in particular to a method for improving free fiber filaments in aqueous solution of sodium carboxymethylcellulose. Background technique [0002] The aqueous solution of sodium carboxymethyl cellulose has the functions of thickening, bonding, film forming, protective glue, water retention, emulsification and suspension, etc. It is widely used in detergent, food, textile, printing and dyeing, papermaking, petroleum, mining, medicine, ceramics , coatings, cosmetics and other industries, known as the "monosodium glutamate" of industry. [0003] The general steps of the existing sodium carboxymethyl cellulose preparation method are a single type of cellulose, such as refined cotton or wood pulp, and sodium hydroxide, chloroacetic acid, ethanol solution through alkalization and etherification to obtain crude The sodium carboxymethyl cellulose product, the material is neutralized...

AI Technical Summary

Problems solved by technology

In the prior art, the alkalization process usually needs to be carried out at a relatively low temperature, generally controlled below 35°C, so as to reduce the reaction rate and make the alkalization reaction proceed evenly and smoothly.

[0004] However, the alkalization reaction at a lower temperature requires a longer reaction time to complete the alkalization reaction, and the free fiber content in the product aqueous solution is higher, that is to say, even if the alkalization time is increased, the material that has not been alkalized completely There are still a lot of water-insoluble cellulose, which limits the application of sodium carboxymethyl cellulose in fields with high requirements for free fiber filaments, such as food industry, pharmaceutical industry and other application fields