CN-121975299-A - Preparation method of high-strength low-rewet composite water-absorbent resin based on polyurethane double-network interpenetrating structure

CN121975299ACN 121975299 ACN121975299 ACN 121975299ACN-121975299-A

Abstract

The invention discloses a preparation method of a high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure, which comprises the following preparation steps of S1, adding a cyclic carbonate derivative, polyamine and water into a reaction container with a stirring function, mixing, and preparing gel. S2, taking out the gel obtained by the reaction, cutting the gel into small pieces, and putting the small pieces into a granulator to be mixed with hot water for primary granulation. And S3, after granulating, placing the gel into a baking oven at 150-200 ℃ to dry water, after a crushing procedure, preparing the gel into abrasive according to particle size distribution, performing surface treatment at high temperature by using a surface treatment liquid, and uniformly mixing the surface treatment liquid with quantitative inorganic powder after cooling to obtain the ultra-high gel strength composite material.

Inventors

YANG WEIDONG
XIE YUAN
RUAN YULIN
ZHU YALIANG
LIU XIN
REN GAOMING
WU YANMIN

Assignees

浙江卫星新材料科技有限公司

Dates

Publication Date: 20260505
Application Date: 20251230

Claims (8)

1. A preparation method of high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure is characterized in that, The preparation method comprises the following preparation steps: s1, adding a cyclic carbonate derivative, polyamine and water into a reaction container with a stirring function, uniformly mixing, adding an acrylic monomer, dropwise adding an internal crosslinking agent and a high-temperature initiator while stirring, uniformly stirring, then placing into a cold water tank for cooling, introducing nitrogen from the bottom, cooling the solution to an initiation temperature, adding a low-temperature initiator, and when the reaction temperature rises to the highest temperature, carrying out heat preservation in a baking oven with the temperature of 60-90 ℃ for at least 8 hours; S2, taking out the gel obtained by the reaction, cutting the gel into small blocks, and putting the small blocks into a granulator to be mixed with hot water for primary granulation; And S3, placing the gel into a baking oven at 150-200 ℃ after granulating, drying the water, crushing the gel, preparing the mixture according to particle size distribution to obtain a grinding material, carrying out surface treatment at high temperature by using a surface treatment liquid, and uniformly mixing the surface treatment liquid with inorganic powder after cooling to obtain the ultra-high gel strength composite material.
2. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The cyclic carbonate monomer is at least one of cyclic carbonate, divinyl carbonate and hydroxyethyl carbonate.
3. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The cyclic carbonate monomer is a bis (ethylene carbonate) ether.
4. The preparation method of the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure, which is disclosed in claim 1, is characterized in that the mass ratio of acrylic acid to polyurethane monomer in the reaction system is (5-20): 1.
5. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, And (3) performing secondary granulation on the gel, and adding fine powder into the secondary granulation.
6. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The mass ratio of the fine powder to the acrylic acid is (2-4) 10.
7. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The reducing auxiliary agent is at least one of sodium sulfite, potassium sulfite and ascorbic acid.
8. The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The reducing auxiliary agent is sodium sulfite, and the mass ratio of the addition amount of the reducing auxiliary agent to the acrylic acid is 0.02:1 The method for preparing the high-strength low-rewet composite water-absorbent resin based on the polyurethane double-network interpenetrating structure according to claim 1, which is characterized in that, The particle size distribution of the mill-base is formulated in the range of m600 μm to 425 μm to m425 μm to 300 μm to m300 μm to 150 μm to m150 μm to 45 μm=5:45:50:1.

Description

Preparation method of high-strength low-rewet composite water-absorbent resin based on polyurethane double-network interpenetrating structure Technical Field The invention relates to the technical field of high polymer materials, in particular to a preparation method of a high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure. Background Super absorbent resin (Superabsorbent Polymer, SAP) is a functional polymer material capable of absorbing and locking a large amount of moisture, and is widely applied to the fields of sanitary articles (such as diaper, sanitary towel) agricultural water retention, medical dressing and the like. The conventional SAP (sodium polyacrylate) has extremely high water absorption (hundreds of times of its own weight), but also has poor mechanical properties and low elasticity, and after water absorption, structural collapse occurs, and part of SAP may cause inflammatory reaction in medical application. Polyurethane (PU) is a multifunctional polymer material with excellent mechanical property, elasticity and adjustable chemical structure, and can be introduced into a super absorbent resin system to effectively enhance the mechanical property, adjust the water absorption and water retention capacity and increase the biocompatibility, so that the polyurethane can be used for wound dressing, however, the synthesis of the traditional PU is usually obtained through the addition polymerization reaction of isocyanate and polyalcohol. Although isocyanate is highly reactive and widely used, its chemical nature suffers from some significant drawbacks. Firstly, isocyanates are toxic and their raw materials are under strict supervision. Second, they are very susceptible to hydrolysis, which makes it difficult to synthesize polyurethane in water. For water-soluble polyurethanes or polyurethane hydrogels, they cannot be prepared directly in one step in water due to the rapid hydrolysis of the isocyanate. CN116120689a discloses an acrylic water-absorbent resin with low reverse osmosis and low extractable content and a preparation method thereof. The acrylic acid water-absorbing resin product prepared by the method has lower reverse osmosis and can be used in the fields of cable water resistance and the like. The polymerization is carried out in a solid or organic solvent. If the polyurethane and the water-absorbent resin are required to be combined, the polyurethane and the acrylic monomer must be uniformly mixed in advance in the early stage, and a uniform interpenetrating crosslinked network cannot be formed in situ. The prior art has the following technical problems: 1) Traditional polyurethane polymerization relies on isocyanate monomers, and the risk of monomer toxicity and residue exists; 2) The single-network sodium acrylate resin has low mechanical strength and is easy to return to seepage after absorbing water; 3) Interpenetrating network structure design is mostly focused on chemical crosslinking, and lacks biocompatible acid optimization. In view of the foregoing, there is a need to develop a high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure and a preparation method thereof. Disclosure of Invention The invention aims to provide a preparation method of a high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure, and the composite water-absorbent resin prepared by the method has good performance and has the performance characteristics of high strength and low rewet. In order to achieve the above object, the following technical solutions are adopted: a preparation method of high-strength low-rewet composite water-absorbent resin based on a polyurethane double-network interpenetrating structure, The preparation method comprises the following preparation steps: and S1, adding a cyclic carbonate derivative, polyamine and water into a reaction container with a stirring function, uniformly mixing, adding an acrylic monomer, dropwise adding an internal crosslinking agent and a high-temperature initiator while stirring, uniformly stirring, then placing into a cold water tank for cooling, introducing nitrogen from the bottom, cooling the solution to the initiation temperature, adding a low-temperature initiator, and when the reaction temperature rises to the highest temperature, carrying out heat preservation in a baking oven with the temperature of 60-90 ℃ for at least 8 hours. S2, taking out the gel obtained by the reaction, cutting the gel into small pieces, and putting the small pieces into a granulator to be mixed with hot water for primary granulation. And S3, after granulating, placing the gel into a baking oven at 150-200 ℃ to dry the water, after the crushing procedure, preparing the abrasive according to particle size distribution, performing surface treatment at high temperature by usin