CN114213589A - Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof - Google Patents
Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof Download PDFInfo
- Publication number
- CN114213589A CN114213589A CN202111618980.8A CN202111618980A CN114213589A CN 114213589 A CN114213589 A CN 114213589A CN 202111618980 A CN202111618980 A CN 202111618980A CN 114213589 A CN114213589 A CN 114213589A
- Authority
- CN
- China
- Prior art keywords
- absorbent resin
- salt
- cellulose
- polyacrylic acid
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
- C08F251/02—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof on to cellulose or derivatives thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/24—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/42—Use of materials characterised by their function or physical properties
- A61L15/60—Liquid-swellable gel-forming materials, e.g. super-absorbents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
- B01J20/26—Synthetic macromolecular compounds
- B01J20/261—Synthetic macromolecular compounds obtained by reactions only involving carbon to carbon unsaturated bonds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/285—Treatment of water, waste water, or sewage by sorption using synthetic organic sorbents
Abstract
The invention provides a salt-tolerant polyacrylic acid water-absorbent resin, a preparation method and application thereof, wherein the preparation method comprises the following steps: mixing cellulose containing hydrophobic groups and acrylic acid monomers, and carrying out crosslinking reaction to prepare the salt-resistant polyacrylic acid water-absorbent resin. Cellulose in the salt-tolerant polyacrylic acid water-absorbent resin can provide hydrophilic hydroxyl groups to improve the salt tolerance of the water-absorbent resin, and the hydrophobic groups can form a double-electrical-layer effect with water, so that the swelling property of the water-absorbent resin is enhanced, the salt tolerance of the acrylic acid water-absorbent resin is improved, and the salt-tolerant polyacrylic acid water-absorbent resin can be better applied to a salt-containing environment.
Description
Technical Field
The invention relates to the technical field of high polymer material synthesis, in particular to a salt-resistant polyacrylic acid water-absorbent resin, and a preparation method and application thereof.
Background
The super absorbent resin is a three-dimensionally crosslinked hydrophilic material, can absorb hundreds or thousands of times of its own weight of water to swell into a gel, and can retain water after being subjected to pressure. The resin gel after water absorption can recover the water absorption performance again after being dried, so that the resin gel has no replaceable effect in the fields of medical treatment and health, agriculture, forestry and gardening, food processing, civil construction, oil exploitation and the like.
At present, the super absorbent resin mainly adopts acrylic acid as a monomer for cross-linking polymerization, and the acrylic acid is added into a network structure, so that the super absorbent resin can find important application in the aspects of water adsorption and selective removal of heavy metal ions or dyes.
CN106496381A discloses a method for preparing a high water absorption polyacrylic resin, which takes acrylic acid, acrylate or acrylic acid derivatives as polymerization monomers, and prepares the high water absorption polyacrylic resin under the action of a surfactant and an initiator through aqueous solution polymerization.
CN110092862A discloses a preparation method of acrylic acid type water-absorbing resin, which comprises the following steps: dripping sodium hydroxide solution into a reaction container filled with acrylic acid, continuously stirring, and keeping the temperature below 40 ℃; adding deionized water, and stirring uniformly; adding N, N-methylene bisacrylamide, introducing nitrogen, and stirring until the mixture is uniformly mixed; adding potassium persulfate, slowly heating to the reaction temperature of 60-70 ℃, and stirring for reacting for 2-4 hours to obtain gelatinous super absorbent resin; drying the gel-like super absorbent resin to obtain the finished product of the acrylic acid type water absorbent resin.
CN1872890A discloses a method for preparing acrylic acid type super absorbent resin, which takes acrylic acid and acrylate as raw materials to carry out copolymerization reaction according to two steps of neutralization reaction and cross-linking polymerization reaction. The initiator is a compound oxidation-reduction initiator, and the cross-linking agent is a binary or ternary compound consisting of (methyl) acrylic acid polyol ester, acrylamide or polyol ether compounds. .
However, the swelling property of the super absorbent resin is significantly reduced by the presence of small molecular salt in the external environment, and therefore, a method for improving the salt resistance of the water absorbent resin is needed.
Disclosure of Invention
In order to solve the technical problems, the invention provides a salt-tolerant polyacrylic acid water-absorbent resin, a preparation method and application thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the invention provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps: mixing cellulose containing hydrophobic groups and acrylic acid monomers, and carrying out crosslinking reaction to prepare the salt-resistant polyacrylic acid water-absorbent resin.
According to the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin, cellulose containing hydrophobic groups is selected as the modification of the acrylic resin, wherein the hydrophobic groups can form hydrophobic repulsion interaction with water and form an electric double layer effect together with anion-anion electrostatic repulsion, so that the swelling property of the water-absorbent resin is enhanced, and the salt tolerance of the acrylic acid water-absorbent resin is improved; and hydroxyl in the cellulose can provide hydrophilic performance, so that the salt resistance of the water-absorbent resin is further improved, and the cellulose containing hydrophobic groups and acrylic acid monomers are subjected to cross-linking reaction and then are subjected to mutual synergistic action, so that the obtained polyacrylic acid water-absorbent resin has excellent performance and has better water absorption rate and water absorption rate.
Preferably, the mass ratio of the acrylic monomer to the hydrophobic group-containing cellulose is 1 to 10:1, and may be, for example, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1, but is not limited to the enumerated values, and other values not enumerated within this range are also applicable. The invention further prefers that the mass ratio of the acrylic monomer to the cellulose containing hydrophobic groups is in the above range, and the cellulose has better salt resistance and water absorption performance.
The preparation step of the hydrophobic group-containing cellulose in the present invention is not particularly limited, and any preparation step for hydrophobic group-containing cellulose known to those skilled in the art can be used, and may be adjusted according to the actual process, but it is further preferable to perform the following method, and the preparation step is simpler and the substitution of the hydrophobic group is controllable.
Preferably, the preparation of the hydrophobic group-containing cellulose comprises: mixing organic acid and cellulose, adding anhydride and concentrated sulfuric acid to carry out esterification reaction, and sequentially carrying out precipitation, washing, drying and crushing in water after the esterification reaction to obtain the cellulose containing hydrophobic groups.
The mass ratio of the cellulose to the organic acid, the acid anhydride, and the concentrated sulfuric acid is preferably 1 (15 to 30): (0.05 to 0.1), and examples thereof include 1:15:15:0.05, 1:20:15:0.05, 1:25:15:0.05, 1:30:15:0.05, 1:15:20:0.05, 1:15:25:0.05, 1:15:30:0.05, 1:15:15:0.06, 1:15:15:0.07, 1:15:15:0.08, 1:15:15:0.1, 1:20:20:0.05, and 1:20:15:0.1, and other values not listed in the range may be applied similarly.
Preferably, the esterification reaction temperature is 20 ~ 100 ℃, for example can be 20 degrees, 29 degrees, 38 degrees, 47 degrees, 56 degrees, 65 degrees, 74 degrees, 83 degrees, 92 degrees or 100 degrees C, but not limited to the enumerated values, in this range of other values are also applicable.
Preferably, the esterification reaction time is 10 to 120min, for example, 10min, 23min, 35min, 47min, 59min, 72min, 84min, 96min, 108min or 120min, but not limited to the values listed, and other values not listed in the range are also applicable, preferably 10 to 70 min. It is further preferred in the present invention that the time of the esterification reaction is within this range, and the substitution percentage of the hydrophobic group can be controlled within a specific range.
Preferably, the hydrophobic group in the hydrophobic group-containing cellulose includes an ester group.
Preferably, the cellulose comprises any one or a combination of at least two of nanocellulose, microcrystalline cellulose, hydroxypropyl cellulose, cotton fiber or carboxymethyl cellulose, wherein typical but non-limiting combinations are a combination of nanocellulose and microcrystalline cellulose, hydroxypropyl cellulose and microcrystalline cellulose, nanocellulose and carboxymethyl cellulose, cotton fiber and microcrystalline cellulose, and nanocellulose and carboxymethyl cellulose.
Preferably, the percentage of hydrophobic groups in the hydrophobic group-containing cellulose substituted for hydroxyl groups in the cellulose is 30 to 80%, for example 30%, 36%, 42%, 47%, 53%, 58%, 64%, 69%, 75% or 80%, but not limited to the recited values, and other values not recited in this range are also applicable. According to the invention, the percentage of the hydrophobic groups in the cellulose containing the hydrophobic groups to replace hydroxyl groups in the cellulose is further preferably 30-80%, part of the hydrophilic groups provide hydrophilic performance to ensure water absorption performance, and part of the hydrophobic groups interact with water to form an electric double layer effect, so that the final polyacrylic resin can provide more excellent salt resistance and water absorption performance.
Preferably, an initiator is added to the crosslinking reaction.
Preferably, the initiator comprises any one of ammonium persulfate, potassium persulfate or azobisisobutyrimidazoline hydrochloride or a combination of at least two of the foregoing, wherein typical but non-limiting combinations are a combination of ammonium persulfate and potassium persulfate, a combination of ammonium persulfate and azobisisobutyrimidazoline hydrochloride, and a combination of azobisisobutyrimidazoline hydrochloride and potassium persulfate.
Preferably, the mass ratio of the initiator to the acrylic monomer is 0.4 to 0.9:100, and may be, for example, 0.4:100, 0.5:100, 0.6:100, 0.7:100, 0.8:100, or 0.9:100, but is not limited to the values listed, and other values not listed in this range are also applicable.
Preferably, a cross-linking agent is added to the cross-linking reaction.
Preferably, the cross-linking agent comprises any one or a combination of at least two of N, N-methylene bisacrylamide, ethylene glycol diacrylate or acrylic acid acrylate, wherein typical but non-limiting combinations are a combination of N, N-methylene bisacrylamide and ethylene glycol diacrylate, a combination of acrylic acid acrylate and ethylene glycol diacrylate, and a combination of N, N-methylene bisacrylamide and acrylic acid acrylate.
The cross-linking agent and the initiator are further optimized, and the prepared product has better water absorption performance and salt resistance.
Preferably, the mass ratio of the crosslinking agent to the acrylic monomer is 0.4 to 1:100, and may be, for example, 0.4:100, 0.5:100, 0.6:100, 0.7:100, 0.8:100, 0.9:100, or 1:100, but is not limited to the above-mentioned values, and other values not mentioned in this range are also applicable.
Preferably, a neutralizing solution is added to the crosslinking reaction.
Preferably, the neutralizing solution comprises a base solution.
Preferably, the molar concentration of the alkali solution is 0.5 to 2mol/L, and may be, for example, 0.5mol/L, 0.7mol/L, 0.9mol/L, 1mol/L, 1.2mol/L, 1.4mol/L, 1.5mol/L, 1.7mol/L, 1.9mol/L or 2mol/L, etc., but is not limited to the values listed, and other values not listed in this range are also applicable.
Preferably, the alkali solution comprises a sodium hydroxide solution.
The mass ratio of the neutralizing solution to the acrylic acid monomer is preferably 50 to 80:100, and may be, for example, 50:100, 54:100, 57:100, 60:100, 64:100, 67:100, 70:100, 74:100, 78:100 or 80:100, but is not limited to the above-mentioned values, and other values not mentioned in the above range are also applicable.
Preferably, the temperature of the crosslinking reaction is 40 to 60 ℃, for example, 40 ℃, 43 ℃, 45 ℃, 47 ℃, 49 ℃, 52 ℃, 54 ℃, 56 ℃, 58 ℃ or 60 ℃, but not limited to the cited values, and other values not listed in the range are also applicable.
Preferably, after mixing the cellulose containing hydrophobic groups and the acrylic acid monomer, preheating and dispersing are carried out, then the solution for neutralization is added, stirring is carried out, then the cross-linking agent and the initiator are added, and the cross-linking reaction is carried out by continuous stirring.
Preferably, the stirring time is 1.5 to 4 hours, for example, 1.5 hours, 1.8 hours, 2 hours, 2.5 hours, 3 hours, 3.2 hours, 3.5 hours or 4 hours, etc., but not limited to the recited values, and other values not recited in the range are also applicable.
Preferably, the temperature of the pre-heating dispersion is 40 to 60 ℃, for example, 40 ℃, 43 ℃, 45 ℃, 47 ℃, 49 ℃, 52 ℃, 54 ℃, 56 ℃, 58 ℃ or 60 ℃, but not limited to the recited values, and other values not recited in the range are also applicable.
Preferably, the time for preheating and dispersing is 20-60 min, such as 20min, 25min, 29min, 34min, 38min, 43min, 47min, 52min, 56min or 60min, but not limited to the recited values, and other values not recited in the range are also applicable.
Preferably, after the crosslinking reaction, the method further comprises the steps of sequentially carrying out solid-liquid separation, drying, crushing and screening to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Preferably, the size of the screen is 50 to 100 mesh, for example, 50 mesh, 60 mesh, 65 mesh, 70 mesh, 80 mesh, 90 mesh or 100 mesh, etc., but is not limited to the listed values, and other values not listed in the range are also applicable.
The solid-liquid separation in the above process is not particularly limited in the present invention, and any device and method for solid-liquid separation known to those skilled in the art can be used, and may be adjusted according to the actual process, such as filtration, centrifugation, or sedimentation, or may be a combination of different methods.
The drying in the above process is not limited in any way, and any device and method for drying known to those skilled in the art can be used, and can be adjusted according to the actual process, such as air drying, vacuum drying, oven drying or freeze drying, or a combination of different methods.
The present invention also has no special limitation on the pulverization in the above process, and any device and method for pulverization known to those skilled in the art can be used, and can be adjusted according to the actual process, such as grinding, extrusion pulverization, splitting pulverization or impact pulverization, and the like, or a combination of different methods.
As a preferable technical solution of the first aspect of the present invention, the preparation method comprises:
mixing 30-80% of hydrophobic group-containing cellulose and an acrylic acid monomer, wherein the mass ratio of the acrylic acid monomer to the hydrophobic group-containing cellulose is 1-10: 1, preheating and dispersing at 40-60 ℃ for 20-60 min, adding a sodium hydroxide solution with the molar concentration of 0.5-2 mol/L, stirring, adding a crosslinking agent and an initiator, wherein the mass ratio of the crosslinking agent to the acrylic acid monomer is 0.4-1: 100, the mass ratio of the initiator to the acrylic acid monomer is 0.4-0.9: 100, and continuously stirring for crosslinking reaction;
and after the crosslinking reaction, sequentially carrying out solid-liquid separation, drying, crushing and 50-100 mesh screening to obtain the salt-resistant polyacrylic acid water-absorbent resin.
In a second aspect, the invention provides a salt-tolerant polyacrylic acid water-absorbent resin, which is prepared according to the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin in the first aspect.
The polyacrylic acid water-absorbent resin prepared by the first aspect of the invention has salt resistance and high water absorption performance, and has a wide application prospect.
In a third aspect, the invention provides a use of the salt-tolerant polyacrylic acid water-absorbent resin according to the first aspect in a salt-containing environment.
The polyacrylic acid water-absorbent resin can be applied to salt-containing environments, such as paper diapers for infants, medical operation pads, soil water retention for agriculture and forestry, sewage treatment and other fields.
Compared with the prior art, the invention has at least the following beneficial effects:
(1) the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin provided by the invention can keep better water absorption rate and water absorption rate while meeting the requirement of good salt water resistance, and the water absorption capacity of the salt-tolerant polyacrylic acid water-absorbent resin to 0.9% saline water is more than 34g/g, even more than 92 g/g; the water absorption capacity of pure water can reach more than 235g/g, the absorption speed of saline can reach 0.48 g/g.s, the water absorption capacity of pure water can reach more than 268g/g under better conditions, and the absorption speed of saline can reach more than 1.10 g/g.s;
(2) the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin provided by the invention takes the natural polymer as one of the synthetic raw materials of the high-water-absorbent resin, and has the advantages of wide source and lower cost.
Detailed Description
For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
As a specific embodiment of the present invention, there is provided a preparation method of a salt-tolerant polyacrylic acid water absorbent resin, the preparation method comprising:
mixing 30-80% of hydrophobic group-containing cellulose and an acrylic acid monomer, wherein the mass ratio of the acrylic acid monomer to the hydrophobic group-containing cellulose is 1-10: 1, preheating and dispersing at 40-60 ℃ for 20-60 min, adding a sodium hydroxide solution with the molar concentration of 0.5-2 mol/L, stirring, adding a crosslinking agent and an initiator, wherein the mass ratio of the crosslinking agent to the acrylic acid monomer is 0.4-1: 100, the mass ratio of the initiator to the acrylic acid monomer is 0.4-0.9: 100, and continuously stirring for 1.5-4 h to perform crosslinking reaction;
and after the crosslinking reaction, sequentially carrying out solid-liquid separation, drying, crushing and 50-100 mesh screening to obtain the salt-resistant polyacrylic acid water-absorbent resin.
The following will explain in detail by taking specific examples as examples.
Example 1
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 1g of nano-cellulose into 20mL of acetic acid in advance for activation, then dropwise adding 20mL of acetic anhydride and 0.05g of 98% sulfuric acid at a concentration for esterification reaction at 40 ℃ for 20min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the nano-cellulose containing hydrophobic groups with the group substitution percentage of 40% according to GB/T32117-2015 analysis and calculation;
mixing 1g of nano-cellulose containing 40% of hydrophobic groups and 10g of acrylic acid monomer, preheating and dispersing at 45 ℃ for 60min, adding 5g of sodium hydroxide solution with the molar concentration of 2mol/L, uniformly stirring, adding 0.06g of N, N-methylene bisacrylamide, 0.04g of ammonium persulfate and 0.04g of azobisisobutyrimidazoline hydrochloride, and continuously stirring for 2h to perform a crosslinking reaction;
and filtering, drying, crushing and screening by 50 meshes in sequence after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 2
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 3g of carboxymethyl cellulose into 45mL of propionic acid in advance for activation, then dropwise adding 45mL of propionic anhydride and 0.1g of 98% sulfuric acid at 45 ℃ for esterification reaction for 30min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the hydrophobic group-containing carboxymethyl cellulose with the group substitution percentage of 50% according to GB/T32117-2015 analysis and calculation;
mixing 2g of carboxymethyl cellulose containing 50% of hydrophobic groups and 18g of acrylic acid monomer, preheating and dispersing at 55 ℃ for 40min, adding 10g of sodium hydroxide solution with the molar concentration of 1mol/L, uniformly stirring, adding 0.09g of ethylene glycol diacrylate, 0.04g of potassium persulfate and 0.05g of azobisisobutyronitrile imidazoline hydrochloride, and continuously stirring for 1.5h to perform crosslinking reaction;
and filtering, drying, crushing and 80-mesh screening are sequentially carried out after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 3
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 2g of microcrystalline cellulose into 50mL of butyric acid in advance for activation, then dropwise adding 60mL of butyric anhydride and 0.2g of 98% sulfuric acid at a concentration for esterification reaction at 40 ℃ for 10min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the microcrystalline cellulose containing hydrophobic groups with a group substitution percentage of 60% according to GB/T32117-2015 analysis and calculation;
mixing 2g of microcrystalline cellulose containing 60% of hydrophobic groups and 20g of acrylic acid monomer, preheating and dispersing at 60 ℃ for 20min, adding 16g of sodium hydroxide solution with the molar concentration of 0.5mol/L, uniformly stirring, adding 0.16g of N, N-methylene bisacrylamide, 0.1g of ammonium persulfate and 0.09g of azobisisobutyrimidazoline hydrochloride, and continuously stirring for 4h to perform crosslinking reaction;
and filtering, drying, crushing and 100-mesh screening are sequentially carried out after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 4
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 2g of microcrystalline cellulose into 40mL of acetic acid in advance for activation, then dropwise adding 50mL of acetic anhydride and 0.05g of 98% sulfuric acid at 60 ℃ for esterification reaction for 10min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the microcrystalline cellulose containing hydrophobic groups with the group substitution percentage of 30% according to GB/T32117-2015 analysis and calculation;
mixing 2g of microcrystalline cellulose containing 30% of hydrophobic groups and 18g of acrylic acid monomer, preheating and dispersing at 50 ℃ for 20min, adding 16g of sodium hydroxide solution with the molar concentration of 1mol/L, uniformly stirring, adding 0.1g of acrylic acid allyl ester and 0.08g of ammonium persulfate, and continuously stirring for 3h to perform crosslinking reaction;
and filtering, drying, crushing and 100-mesh screening are sequentially carried out after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 5
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 2g of hydroxypropyl cellulose into 40mL of caprylic acid in advance for activation, then dropwise adding 40mL of caprylic anhydride and 0.05g of 98% sulfuric acid at a concentration for esterification reaction at 40 ℃ for 60min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the hydroxypropyl cellulose containing the hydrophobic group with the group substitution percentage of 30% according to GB/T32117-2015 analysis calculation;
mixing 1.5g of hydroxypropyl cellulose containing 30% of hydrophobic groups and 15g of acrylic acid monomer, preheating and dispersing at 40 ℃ for 20min, adding 16g of sodium hydroxide solution with the molar concentration of 1mol/L, uniformly stirring, adding 0.1g of acrylic acid propylene ester, 0.04g of ammonium persulfate and 0.04g of azobisisobutyrimidazoline hydrochloride, and continuously stirring for 2h to perform crosslinking reaction;
and filtering, drying, crushing and 100-mesh screening are sequentially carried out after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 6
The embodiment provides a preparation method of a salt-tolerant polyacrylic acid water-absorbent resin, which comprises the following steps:
adding 2g of cotton fiber into 40mL of acetic acid in advance for activation, then dropwise adding 40mL of acetic anhydride and 0.05g of 98% sulfuric acid at 40 ℃ for esterification reaction for 60min, after the reaction is finished, immersing the mixture into deionized water for precipitation, washing, drying and crushing, and obtaining the cotton cellulose containing the hydrophobic group with the group substitution percentage of 30% according to GB/T32117-2015 analysis and calculation;
mixing 1g of cotton cellulose containing 30% of hydrophobic groups and 10g of acrylic acid monomer, preheating and dispersing at 40 ℃ for 20min, adding 6g of sodium hydroxide solution with the molar concentration of 1mol/L, uniformly stirring, adding 0.05g of ethylene glycol diacrylate, 0.01g of ammonium persulfate and 0.03g of azobisisobutyronitrile imidazoline hydrochloride, and continuously stirring for 2h to perform crosslinking reaction;
and filtering, drying, crushing and 80-mesh screening are sequentially carried out after the crosslinking reaction to obtain the salt-resistant polyacrylic acid water-absorbent resin.
Example 7
The preparation process was similar to that of example 1, except that: the esterification reaction time is 80min, and the nanocellulose containing the hydrophobic groups with the group substitution percentage of 95% is obtained by calculation according to GB/T32117-2015 analysis.
Example 8
The preparation process was similar to that of example 1, except that: the esterification reaction time is 5min, and the nanocellulose containing the hydrophobic groups with the group substitution percentage of 20% is obtained by calculation according to GB/T32117-2015 analysis.
Example 9
The preparation process was similar to that of example 1, except that: the mass of cellulose mixed with acrylic acid monomer was 20 g.
Example 10
The preparation process was similar to that of example 1, except that: the mass of cellulose mixed with acrylic monomer was 0.1 g.
Comparative example 1
The comparative example provides a preparation method of polyacrylic acid water-absorbent resin, which is the same as that in example 1 except that cellulose is not added, and specifically comprises the following steps:
preheating 10g of acrylic acid monomer at 45 ℃ for 60min, adding 5g of sodium hydroxide solution with the molar concentration of 2mol/L, uniformly stirring, adding 0.06g of N, N-methylene-bisacrylamide, 0.04g of ammonium persulfate and 0.04g of azobisisobutyrimidazoline hydrochloride, and continuously stirring for carrying out a crosslinking reaction;
and filtering, drying, crushing and screening by a 50-mesh sieve in sequence after the crosslinking reaction to obtain the polyacrylic acid water-absorbent resin.
Comparative example 2
This comparative example provides a method for preparing a polyacrylic acid water absorbent resin, which is the same as example 1 except that nanocellulose having an unmodified hydrophobic group was directly added.
Comparative example 3
This comparative example provides a production method of a water absorbent resin, which was carried out using example 1 described in CN 102633944A.
In the embodiment 1, the cellulose macromolecular chain containing the hydrophobic groups is directly added, so that the hydrophobic groups are uniformly dispersed, and the hydrophobic groups distributed on the macromolecular chain are favorable for stretching a net structure and retaining water; in contrast, in comparative example 3, although carboxymethyl cellulose powder was added, carboxymethyl cellulose powder itself was mainly hydrophilic group, and it was necessary to provide hydrophobic group by acrylic hydrophobic monomer lauryl methacrylate, and the water absorption effect was poor.
The following tests on the water absorption performance of the cellulose modified polyacrylic acid super absorbent resin containing hydrophobic groups obtained in examples 1 to 10 of the present invention and comparative examples 1 to 2 were carried out according to GB/T20405.5-2006, and the test results are shown in Table 1.
TABLE 1
From the experimental results in table 1, it can be seen that:
(1) from the comprehensive examples 1 to 6, the cellulose modified polyacrylic acid super absorbent resin containing the hydrophobic groups prepared by the invention has good salt tolerance, the water absorption capacity of 0.9% saline is more than 78g/g, even more than 92g/g, and the good salt tolerance is caused by the combined action of hydrophilic groups and hydrophobic groups contained in the cellulose, the hydrophobic groups contained in the cellulose and water form hydrophobic interaction, and the hydrophobic groups and anion-anion electrostatic repulsion form an electric double layer effect, so that the swelling property of the water absorbent resin is enhanced, and the salt tolerance of the acrylic acid water absorbent resin is improved; the water absorption capacity of pure water can reach more than 268g/g, and the absorption speed of saline can reach more than 1.10 g/g.s;
(2) it can be seen from the comprehensive results of examples 1 and 7 to 8 that, in example 1, nanocellulose containing 40% of hydrophobic groups is used, compared with nanocellulose containing 95% and 20% of hydrophobic groups in examples 7 to 8, pure water absorption of 285g/g, saline water absorption of 0.9% of 78g/g and saline water absorption rate of 1.10g/g · s are obviously reduced in example 1, and pure water absorption, saline water absorption and water absorption rate are obviously reduced in example 7, but the pure water absorption and the saline water absorption rate are obviously reduced in example 8, which shows that the salt tolerance of the final polyacrylic acid water-absorbent resin is obviously improved by controlling the content of the hydrophobic groups in the cellulose containing the hydrophobic groups within a specific range;
(3) it can be known from the comprehensive examples 1 and 9-10 that the influence of the cellulose and the acrylic acid monomer on the water absorption performance and the salt tolerance of the final polyacrylic acid water-absorbent resin is large, and the salt tolerance and the water absorption performance of the polyacrylic acid water-absorbent resin can be improved by preferably controlling the mass ratio of the acrylic acid monomer to the cellulose containing the hydrophobic group within a specific range;
(4) it can be seen from the comprehensive examples 1 and 1-2 that, compared with the comparative examples 1-2 in which no or unmodified nanocellulose is added, the water absorption performance and salt tolerance of the nanocellulose containing hydrophobic groups added in example 1 are much higher than those of comparative examples 1-2, which indicates that the hydrophobic groups in the final resin and water form hydrophobic interaction by using the cellulose containing hydrophobic groups, and form an electric double layer effect together with anion-anion electrostatic repulsion, thereby improving the water absorption and salt tolerance.
In conclusion, the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin provided by the invention can prepare the polyacrylic acid water-absorbent resin with strong water absorption and high salt tolerance, the water absorption capacity of the polyacrylic acid water-absorbent resin to 0.9% saline water is more than 34g/g, even more than 92g/g, the water absorption capacity of pure water can reach more than 235g/g, and the saline water absorption speed can reach 0.48 g/g.s.
The applicant states that the present invention is illustrated by the above examples to show the detailed process equipment and process flow of the present invention, but the present invention is not limited to the above detailed process equipment and process flow, i.e. it does not mean that the present invention must rely on the above detailed process equipment and process flow to be implemented. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.
Claims (10)
1. A preparation method of salt-resistant polyacrylic acid water-absorbent resin is characterized by comprising the following steps:
mixing cellulose containing hydrophobic groups and acrylic acid monomers, and carrying out crosslinking reaction to prepare the salt-resistant polyacrylic acid water-absorbent resin.
2. The method according to claim 1, wherein the mass ratio of the acrylic monomer to the hydrophobic group-containing cellulose is 1 to 10: 1.
3. The production method according to claim 1 or 2, characterized in that the hydrophobic group in the hydrophobic group-containing cellulose includes an ester group;
preferably, the cellulose comprises any one or a combination of at least two of nanocellulose, microcrystalline cellulose, hydroxypropyl cellulose, cotton fiber or carboxymethyl cellulose;
preferably, the percentage of the hydrophobic groups in the cellulose containing the hydrophobic groups to replace the hydroxyl groups in the cellulose is 30-80%.
4. The method according to any one of claims 1 to 3, wherein an initiator is added in the crosslinking reaction;
preferably, the initiator comprises any one of ammonium persulfate, potassium persulfate or azobisisobutyrimidazoline hydrochloride or a combination of at least two of the ammonium persulfate, the potassium persulfate or the azobisisobutyrimidazoline hydrochloride;
preferably, the mass ratio of the initiator to the acrylic monomer is 0.4-0.9: 100.
5. The method according to any one of claims 1 to 4, wherein a crosslinking agent is added in the crosslinking reaction;
preferably, the cross-linking agent comprises any one or a combination of at least two of N, N-methylene bisacrylamide, ethylene glycol diacrylate or acrylic acrylate;
preferably, the mass ratio of the cross-linking agent to the acrylic monomer is 0.4-1: 100.
6. The production method according to any one of claims 1 to 5, wherein a neutralizing solution is added in the crosslinking reaction;
preferably, the neutralizing solution comprises a base solution;
preferably, the molar concentration of the alkali solution is 0.5-2 mol/L;
preferably, the alkali solution comprises a sodium hydroxide solution;
preferably, the mass ratio of the neutralizing solution to the acrylic acid monomer is 50-80: 100.
7. The method according to any one of claims 1 to 6, wherein the temperature of the crosslinking reaction is 40 to 60 ℃;
preferably, after mixing the cellulose containing hydrophobic groups and the acrylic acid monomer, preheating and dispersing, adding the neutralization solution, stirring, adding the cross-linking agent and the initiator, and continuously stirring for cross-linking reaction;
preferably, the preheating and dispersing temperature is 40-60 ℃;
preferably, the preheating and dispersing time is 20-60 min.
8. The preparation method according to any one of claims 1 to 7, characterized in that the crosslinking reaction is followed by solid-liquid separation, drying, crushing and screening in sequence to obtain the salt-tolerant polyacrylic acid water-absorbent resin;
preferably, the size of the screening is 50-100 meshes.
9. A salt-tolerant polyacrylic acid water-absorbent resin, which is characterized by being prepared according to the preparation method of the salt-tolerant polyacrylic acid water-absorbent resin of any one of claims 1 to 8.
10. Use of the salt-tolerant polyacrylic acid water-absorbent resin according to claim 9 in a salt-containing environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111618980.8A CN114213589A (en) | 2021-12-27 | 2021-12-27 | Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111618980.8A CN114213589A (en) | 2021-12-27 | 2021-12-27 | Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114213589A true CN114213589A (en) | 2022-03-22 |
Family
ID=80706272
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111618980.8A Pending CN114213589A (en) | 2021-12-27 | 2021-12-27 | Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114213589A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101240034A (en) * | 2008-03-14 | 2008-08-13 | 中国科学院广州化学研究所 | Method for preparing cellulose acetate butyrate |
| CN107417858A (en) * | 2017-07-21 | 2017-12-01 | 南京理工大学 | A kind of preparation method of the composite high-water-absorptivresin resin comprising diatomite and cellulose |
| CN110423308A (en) * | 2019-03-12 | 2019-11-08 | 北京市政建设集团有限责任公司 | The preparation method of a kind of super absorbent resin and in the application for reducing dregs moisture content |
-
2021
- 2021-12-27 CN CN202111618980.8A patent/CN114213589A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101240034A (en) * | 2008-03-14 | 2008-08-13 | 中国科学院广州化学研究所 | Method for preparing cellulose acetate butyrate |
| CN107417858A (en) * | 2017-07-21 | 2017-12-01 | 南京理工大学 | A kind of preparation method of the composite high-water-absorptivresin resin comprising diatomite and cellulose |
| CN110423308A (en) * | 2019-03-12 | 2019-11-08 | 北京市政建设集团有限责任公司 | The preparation method of a kind of super absorbent resin and in the application for reducing dregs moisture content |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Synthesis, characterization and swelling behavior of superabsorbent wheat straw graft copolymers | |
| CN110270317A (en) | A kind of preparation method of the cellulose base hydrogel adsorbent for heavy metal containing wastewater treatment | |
| JPH02191604A (en) | Water-absorbing resin and production thereof | |
| KR970009239B1 (en) | Process for producing highly water absorptive polymer | |
| CN102659988B (en) | Preparation method of straw-based high-water-absorption resin with semi-interpenetrating network structure | |
| CN101045776A (en) | Method for synthesizing high water absorption resin by glutinous wheat starch | |
| CN106565913A (en) | Preparation method of urea-wrapped cellulose-based super absorbent resin | |
| CN107722163B (en) | Acrylic acid water-absorbent resin, water-absorbent resin with low soluble component and application thereof | |
| CN103087263B (en) | Preparation method of crosslinked AM/AA (acrylamide/acrylic acid) grafted xanthic acid esterification tapioca starch | |
| CN104448161A (en) | Organic composite hydrogel cross-linked by modified gelatin nano-microsphere and preparation method of organic composite hydrogel | |
| EP2771104A1 (en) | Highly swellable polymers | |
| JPH0725810B2 (en) | Super absorbent resin manufacturing method | |
| CN103130965B (en) | A kind of Humic acid type superabsorbent resin and preparation method thereof | |
| CN107602780A (en) | A kind of lignite humic acid base super absorbent resin epoxy-type agricultural water-loss reducer and preparation method thereof | |
| JP2018145210A (en) | Novel acrylic acid crosslinked polymer and use thereof | |
| CN104004521A (en) | Preparation method of bagasse pith nanometer cellulose-based composite water-retaining agent | |
| JPH0625209B2 (en) | Water absorbent resin and method for producing the same | |
| CN101838368A (en) | Method for preparing acrylic acid/montmorillonite nano composite material | |
| CN105131208B (en) | The preparation method of rice hull carbon base water-retaining agent and rice hull carbon base water-retaining agent | |
| CN110372833A (en) | A method of degradable high hydroscopic resin is prepared with bamboo scraps | |
| CN101974192A (en) | Intelligent high water absorption and waterholding material and preparation method and application thereof in desertification control | |
| CN114213589A (en) | Salt-tolerant polyacrylic acid water-absorbent resin and preparation method and application thereof | |
| Li et al. | UV polymerization and property analysis of maleacylated methyl cellulose acrylic acid absorbent resin | |
| CN110734553A (en) | Preparation method of degradable super absorbent resins | |
| CN111138593A (en) | Simple preparation method and application of composite high-adsorption resin |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |