Treatment method for improving surface crosslinking of water-absorbent resin via vacuum negative-pressure

Abstract

A treatment method for improving surface crosslinking of a water-absorbent resin via vacuum negative-pressure comprises: (1) putting 100 parts by mass of to-be-treated water-absorbent resin particlesand 6-15 parts by mass of a surface treatment fluid in a stirrer; (2) connecting a vacuum pump to the stirrer and setting the vacuum degree of the vacuum pump to be 0.04-0.08 Mpa; (3) making the stirrer stir in a vacuum environment for 40-60 min; and (4) when the stirrer is operated, collecting an organic solvent component in the surface treatment fluid, wherein the organic solvent component is volatilized from the stirring via the vacuum pump. According to the method, the content of the organic solvent left in the water-absorbent resin is obviously reduced. During the treatment process, the speed of surface treatment is increased, a worker basically doesn't contact the organic solvent, and the organic solvent can be efficiently recycled.

Description

technical field [0001] The invention belongs to the field of macromolecule materials, and in particular relates to a treatment method for improving cross-linking of water-absorbing resin surface by vacuum negative pressure. Background technique [0002] Super Absorbent Polymer (SAP) is a new type of functional polymer material with a large number of hydrophilic groups. It has a high water absorption function of absorbing water hundreds to thousands of times heavier than itself, and has excellent water retention performance. Once it absorbs water and swells into a hydrogel, it is difficult to separate the water even if it is pressurized. Water-absorbing resins are widely used and have a very broad application prospect. The main purpose is mainly sanitary materials, accounting for about 70% of the total market. [0003] The preparation process of the water-absorbent resin mainly includes the steps of neutralization, polymerization, granulation, drying, pulverization, surface...

AI Technical Summary

Problems solved by technology

However, since the water-absorbent resin itself cannot absorb organic solvents, and there is no step for recovering organic solvents in the existing surface treatment process, organic solvents usually remain in the water-absorbent resin

If the organic solvent remains in the water-absorbent resin, the water-absorbing performance of the water-absorbent resin will decrease, and it may also cause irritation to human skin

Generally speaking, the water-absorbent resin used in diapers must meet the national standards before it can be marketed, so the residual organic solvents in the water-absorbent resin will not cause obvious adverse effects on users; but since infants and young children are the main population of diapers , whose skin is far more delicate and fragile than that of adults. Therefore, even if the existing water-absorbent resin used in baby diapers and other products whose organic solvent residues meet the national standards, the residual amount is close to the critical point, it may still be harmful to the Irritation of the skin of infants and young children, causing problems such as rashes

[0005] In addition, due to the high volatility of organic solvents, there is an inevitable heating process in the preparation of water-absorbent resins, and organic solvents are more likely to volatilize in the air. At the same time, most organic solvents are flammable. There is a risk of explosion in the process, so the existing water-absorbent resin preparation process has potential safety hazards

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