A process for producing superabsorbent particles by polymerizing a monomer solution or suspension, comprising drying of the resultant aqueous polymer gel in an air circulation belt dryer, grinding, classifying, and optionally thermal surface postcrosslinking, wherein the aqueous polymer gel is introduced into the air circulation belt dryer by means of an oscillating conveyor belt and that guide devices are located at the edges of the conveyor belt.

The present disclosure relates to a super absorbent polymer exhibiting improved rewetting property and excellent absorption property, and a preparation method of the same. This preparation method of a super absorbent polymer includes the steps of: preparing a base resin in which an acrylic acid-based monomer having at least partially neutralized acidic groups and an internal cross-linking agent are cross-linked and polymerized; and heating the base resin in the presence of a surface cross-linking agent to carry out surface modification, wherein the internal cross-linking agent includes a poly(meth)acrylate of polyols-based first internal cross-linking agent and a polyglycidyl ether of polyols-based second internal cross-linking agent in a specific weight ratio.

The present invention relates to a process for preparation of superabsorbent polymer with high fluid absorptivity. The present invention also relates to a composition comprising said superabsorbent polymer particles and their use for absorbing aqueous fluids, for example in the agricultural industry.

A method for preparing superabsorbent polymer is disclosed herein. In some embodiments, a method includes polymerizing a monomer composition to form a hydrogel polymer, wherein the monomer composition comprises a water soluble ethylenically unsaturated monomer and a polymerization initiator, drying and grinding the hydrogel polymer to prepare a base resin powder, surface cross-linking the base resin powder using a surface cross-linking agent to prepare surface cross-linked base resin powder, and hydrating the surface cross-linked base resin powder by pulse spraying water to prepare a superabsorbent polymer, wherein a scattering index of droplets generated during the pulse spraying is 5 to 10, and wherein the scattering index is calculated in accordance with the following Mathematical Formula 1. The superabsorbent polymer can have an improved moisture content to prevent surface property change of the superabsorbent polymer, and decreased amount of fine powder which improves processability during manufacture of articles using superabsorbent polymer.

A method of preparing a superabsorbent polymer includes preparing a base resin in which an acrylic acid-based monomer having acidic groups which are at least partially neutralized and an internal crosslinking agent are crosslinked in the presence of a sodium polycarboxylate surfactant; and heating the base resin in the presence of a surface crosslinking agent to carry out surface modification of the base resin, wherein the internal crosslinking agent includes a first epoxy crosslinking agent having an epoxy equivalent weight of 100 g/eq or more to less than 130 g/eq, and a second epoxy crosslinking agent having an epoxy equivalent weight of 130 g/eq or more. The superabsorbent polymer provides improved rewetting property and liquid permeability.

Method for preparing a natural organic macromolecular water treatment agent including: dissolving amylose corn starch in an alkali solution, stirring for 30 min, to obtain a suspension, freezing the suspension to fully frozen state, melting and dialyzing, to obtain a corn starch dispersion; mixing a modified flax fiber, the dispersion, nano-hybrid silica and distilled water, performing 800 W ultrasonication for 10 min, to obtain a treated suspension; taking an amount of a superabsorbent macromolecular resin with a certain shape, making it absorb water and swell into a solid hydrogel with the certain shape; mixing the solid hydrogel and the treated suspension, static defoaming, loading into a mold and solidifying, drying until the solid hydrogel is completely dehydrated, to obtain a hollow agent; spraying a catalytic degrading agent/toxin degrading agent on the surface of the hollow agent and/or the inner wall of holes thereof, to obtain the target agent.

A method of recycling superabsorbent polymers derived from a used absorbent article, the method including: treating the superabsorbent polymers with ozone water after inactivation; reactivating, with an alkaline aqueous solution, the superabsorbent polymers treated with the ozone water; and adding hydrophilic fine particles to the superabsorbent polymers reactivated with the alkaline aqueous solution and then drying the superabsorbent polymers.

Disclosed are water-absorbing resin particles 10a in which an expansion retention rate calculated by the formula: expansion retention rate (%)=(V.sub.1/V.sub.0)×100 is 98% or more. V.sub.0 is the volume of the swollen gel formed when 1.000±0.001 g of the water-absorbing resin particles 10a absorb 20.0±0.1 g of pure water. V.sub.1 is the volume of the swollen gel formed when 1.000±0.001 g of the water-absorbing resin particles 10a absorb 20.0±0.1 g of physiological saline.

The present invention relates to a superabsorbent polymer and a method for producing the same. The superabsorbent polymer includes a core layer polymerized with monomers having carboxylic group, a first shell layer formed from a surface crosslinking agent, and a second shell layer formed from zingiberaceae extracts. By a surface modification on the first shell layer performed from a specific amount of the zingiberaceae extracts, the superabsorbent polymer produced according to the method for producing the same has a good antimicrobial property and deodorizing effects, and retains an original absorbent property.

Poly(acrylic acid)-based superabsorbent polymer (SAP) in a feed stream is converted with UV irradiation into poly(acrylic acid) (PAA) in a flow system. The UV total energy used to convert SAP into PAA is less than about 50 MJ/kg SAP.