CN107828079A - Water-absorbing resins and its manufacture method - Google Patents

Abstract

A kind of water-absorbing resins of the present invention and its manufacture method, it comprises the following steps：Acquisition contains unsaturated acrylic monomer and cross-linking agent aqueous solution；After foaming agent solution is mixed with weak acid and/or weak acid salting liquid, prepare blowing-agent particle dispersion liquid, the foaming agent solution is the compound solution containing primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group, weak acid and/or the weak acid salting liquid is one kind in weak acid solution, weak acid salting liquid or weak acid/weak acid mixed salt solution, and the Blowing agent composition is 10 with weak acid/salt of weak acid constituent mass ratio:1~1:5000, in the blowing-agent particle dispersion liquid, the number average bead diameter of blowing-agent particle is 0.1~900 micron.Its advantage is：A kind of imbibition characteristic for not influenceing water-absorbing resins is provided, can efficiently produce the method for the water-absorbing resins with high speed rate of liquid aspiration, and obtains a kind of water-absorbing resins with high speed rate of liquid aspiration and combinations thereof.

Description

Water-absorbing resins and its manufacture method

Technical field

The present invention relates to a kind of water-absorbing resins and its manufacture method.Absorbent commodity is it is particularly applicable to, such as：Paper nappy (disposable diaper), sanitary napkin, incontinence pad, mattress, pet pads, Wound care material, construction material, soil water-retaining material etc. are made In product, and water-absorbing resins and its manufacture method with quick imbibition performance.

Background technology

High water absorbency polymer (Super absorbent polymer, SAP) is also known as high hydroscopic resin, is that one kind contains Strongly hydrophilic group, it is not soluble in water, but the cross-linked polymer of tens of, hundreds of or even thousands of times of water of deadweight can be absorbed.High water absorption Resin is now widely used in a variety of necks of the amenities and soil moisturizing agent etc. such as paper diaper, physiological hygiene cotton, adult-incontinence articles Domain.In the stage now, there are crosslinked after the neutralization of polyacrylic acid part, Starch and Acrylic Acid graft polymers known to water-absorbing resin Saponified, acrylonitrile copolymer crosslinked, the acrylamide copolymer of hydrolysate, vinyl acetate-acrylate copolymer Crosslinked and cationic monomer crosslinked etc..

In recent years, paper diaper structure develops towards thinner direction, and it needs to reduce fiber content in product, improves simultaneously Absorbent contents, thinner structure not only improve the comfortableness of dress, and can reduce packaging, storage and cost of transportation.More Thin paper diaper structure proposes very big requirement to the performance of absorbent, wherein it is important that water-absorbing resin conduction and distribution Absorptive capacity under the ability of liquid, liquid-keeping property, pressure, especially, absorption rate (the unit mass water absorbing agent of water-absorbing resin Liquid absorption amount within the unit interval) can be in its first time and liquid as paper diaper of the assessment with high content water-absorbing resin Quick absorbing liquid body major criterion when body contacts.However, mutual containing between the multiple performance of water-absorbing resin be present, if greatly Width lifts its rate of liquid aspiration, necessarily causes to conduct and be distributed the bad of absorptive capacity under ability, liquid-keeping property or the pressure of liquid Change, this turns into the development bottleneck with quick imbibition speed water-absorbing resin.

The technology of the existing absorption rate for improving water-absorbing resin mainly includes four kinds：(1) the physically or chemically side of foaming is passed through Method be prepared loose structure water-absorbing resin (such as EP0295438B, WO1994022502A, EP0644207B, EP0538983B、US20050137546A、CN102225981A、US20120258851A、CN103857714A、 CN1668343A、CN1296981A、CN101050244A、CN101143913A、CN101423588A、CN104448155A、 CN102311557A、CN104448102A、CN103214616A、CN103476811A、CN103857714A、 CN105377921A、CN102317329A、CN102010560A)；(2) agglomerated particle type water-absorbing resin is prepared using micro mist granulation (such as EP0591168A)；(3) logical fluidity enhancer (such as special crosslinking agent) lifting water-absorbing resin is added in water-absorbing resin Logical fluidity, further improve its rate of liquid aspiration (such as WO2001089591A)；(4) surface conditioning agent (such as clay, nothing are added Machine material etc.) increase the rate of liquid aspiration of water-absorbing resin (such as US20050239942A, WO2005120221A).Wherein, study More and more effective method is foamed polymer strategy.

In foamed polymer, it is known that have using carbonate, organic solvent, inert gas, heat decomposition type azo-compound, The technologies such as insoluble inorganic powder, other thermal decomposable foaming agents, the technology for also being foamed and being crosslinked after polymerisation.

Patent CN103857714A is disclosed before initiator is added, and 10~900 microns of sodium carbonate particle of granularity is sent out Infusion and can response type surfactant active 4 DEG C be added to monomer solution in, surfactant can stable sodium percarbonate particle and Caused gas after it is decomposed, bubble diameter are smaller.After the completion of polymerization, surfactant participates in polymerisation and forms polymeric web Network, effectively reduce resin in can extraction surface active agent content, meanwhile, gas effectively improves resin caused by soda decomposition Rate of liquid aspiration, the presence of surfactant further lifts rate of liquid aspiration.

Patent EP0538983B is disclosed carbonic acid (hydrogen) salt foaming of 0.2~2.5wt% in terms of acrylic monomers quality Agent is dissolved or dispersed in monomer solution for 15 minutes to after polymerizeing in 5 minutes before polymerization, is carried out triggering at 0~20 DEG C and is gathered Close, the foaming agent being dissolved or dispersed in monomer solution decomposes in a heated condition, discharges carbon dioxide, and it is poly- to carry out foaming Close, effectively improve the rate of liquid aspiration of water-absorbing resin.

Patent CN102311557A discloses a kind of foaming agent for crossing coating processing and is used to prepare quick absorption-type water suction Resin, the carbonate compound mixture that the foaming agent that the coating processing is crossed is crossed for alum class compound coating processing, alum bag After covering carbonate compound, carbonate will not contact with monomer solution immediately, and then prevent that it is molten with monomer in early stage Neutralization reaction occurs for liquid；With the progress of polymerisation, the carbonate compound in foaming agent can be released slowly, be finally given more Hole resin structure, and the polyvalent metal ion in alum is further crosslinked to resin inside, the absorption improved under pressure is held Amount.

Patent CN103476811A is disclosed before initiator is added, and 300~700 microns of particle Rotating fields of granularity are sent out Infusion (carbonate) is added in monomer solution lifting resin rate of liquid aspiration.

Patent CN102317329A discloses dissolving and/or has disperseed the acrylic monomer aqueous solution of gas, is not depositing It is polymerize in surfactant or exist under the conditions of below 300ppm, inert gas micro-bubble is suspended or dissolved in monomer water In solution, polymerization process is rested in polymeric gel, and rate of liquid aspiration is lifted in the case where not influenceing resin surface tension force.

In addition, also some other known rate of liquid aspiration lift techniques.

Patent EP0591168A discloses the method for being reacted surface crosslinking agent and primary granule, and small particle resin is attached It is poly- to be carried out simultaneously with surface-crosslinked, the time started is crosslinked by control surface, realized intergranular surface-crosslinked to lift suction Liquid speed rate.It is surface-crosslinked due to occurring between particle when the primary granule of aggregation contacts with liquid, be not in fine grained point From situation, gel blocking reduces；Agglomeration adds specific surface area, improves absorption rate.

Patent US20050239942A discloses that clay is added in water absorbing resin particle in surface cross-linking step and used To improve rate of liquid aspiration and permeability.

Patent WO2001089591A discloses to be surface-treated with hydroxyalkyl amide to resin, and treatment temperature 100~ 160 DEG C, 90~150 minutes time, improve absorption rate, absorb amount of liquid and gel strength.

These technologies improve resin absorption speed to a certain extent, but in actual production process, can bring liquid Permeability or resin impact resistance declined, the reduction of apparent density, manufacture, transport or use during be also easy to produce it is micro- The problems such as powder or dust.In addition, in order to obtain the more preferable water-absorbing resin of foaming effect, often need to add table in polymerization system Face activating agent, to stablize Air Bubble Size, this can cause the reduction of water-absorbing resin surface tension in use, suppress product Imbibition characteristic.Skill upgrading disclosed in the patent rate of liquid aspiration of water-absorbing resins, but still it is insufficient.

Surfactant is added in polymerization system can influence the surface tension of resin, and then influence the absorbency of product Energy.In addition, if rate of liquid aspiration significantly improves, the impact resistance of resin, the ability of conduction and distribution liquid, liquid energy is protected The imbibition such as absorptive capacity under power, pressure characteristic can deteriorate.

Therefore, it is necessary to which providing a kind of buildup of resin density will not excessively reduce, its imbibition characteristic water imbibition tree is not influenceed Fat and its method.

The content of the invention

The method of the water-absorbing resins with high speed rate of liquid aspiration can be efficiently produced, and obtained a kind of with suction at a high speed The water-absorbing resins of liquid speed rate.

In order to solve described problem, the present invention disperses average in the monomer solution containing unsaturated monomer and crosslinking agent Blowing-agent particle of the particle diameter at 0.1~900 micron, by polymerizeing, being granulated, drying, grinding, sieving, surface-crosslinked absorbed water Property resin, the resistance to bulk density of the resin will not be reduced excessively, conduct and be distributed the suction under the ability of liquid, liquid-keeping property, pressure The imbibition excellent such as collecting amount, and rate of liquid aspiration significantly improves.The product is applied to slimming hygienic articles, can be effective Avoid the fluid leakage problems caused by rate of liquid aspiration deficiency.

To achieve the above object, the present invention provides a kind of manufacture method of water-absorbing resins, and it comprises the following steps：

The step of acquisition contains unsaturated acrylic monomer and cross-linking agent aqueous solution,

After foaming agent solution is mixed with weak acid and/or weak acid salting liquid, the step of preparing blowing-agent particle dispersion liquid,

The foaming agent solution is the compound solution containing primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group,

Weak acid and/or the weak acid salting liquid is in weak acid solution, weak acid salting liquid or weak acid/weak acid mixed salt solution One kind,

The Blowing agent composition is 10 with weak acid/salt of weak acid constituent mass ratio:1~1:5000,

In the blowing-agent particle dispersion liquid, the number average bead diameter of blowing-agent particle is 0.1~900 micron,

The step of blowing-agent particle dispersion liquid is mixed with unsaturated acrylic monomer and cross-linking agent aqueous solution,

The step of blowing-agent particle is polymerize with unsaturated acrylic monomer and crosslinking agent mixed solution,

The step of aqueous gel shaped polymer is crushed in the course of the polymerization process or after polymerization,

The step of being thermally dried to the aqueous gel shaped polymer after crushing,

The step of grain refined is carried out to loose structure cross-linked polymer after drying and is sieved,

Surface crosslinking agent processing screening after water-absorbing resins near surface, formed covalent bond the step of,

With cationic compound processing water-absorbing resins surface, the step of forming ionic bond.

According to the present invention, a kind of water-absorbing resins are obtained, the resin average grain diameter is 200~600 microns, and loose structure is put down Equal aperture is 10~500 microns, and centrifuge retention capacity is 25~50g/g, and it is 10~50sec/ that salt velocity is inhaled in swirl method test G, levels of residual monomers is in below 500ppm.

According to the present invention, a kind of water absorbency resin composition is obtained, said composition includes：Water-absorbing resins, the resin are put down Equal particle diameter is 200~600 microns, and loose structure average pore size is 10~500 microns, and centrifuge retention capacity is 25~50g/g, whirlpool It is 10~50sec/g that salt velocity is inhaled in whirlpool method test, and levels of residual monomers is in below 500ppm；And inorganic powder.

, can be without using table the invention discloses a kind of water-absorbing resins and its manufacture method with high rate of liquid aspiration Manufacturing the water-absorbing resins with high rate of liquid aspiration face activating agent and stability and high efficiency, buildup of resin density will not be reduced excessively, And do not influence the imbibition characteristics such as the absorptive capacity under resin conduction and the distribution ability of liquid, liquid-keeping property, pressure.

Embodiment

Below to the present invention water-absorbing resins and its manufacture method be described in detail, but the scope of the present invention not by It is limited to these explanations.

[1] manufacture method of water-absorbing resins

The water-absorbing resins of the present invention are manufactured by following steps.

The step of acquisition contains unsaturated acrylic monomer and cross-linking agent aqueous solution,

After foaming agent solution is mixed with weak acid and/or weak acid salting liquid, the step of preparing blowing-agent particle dispersion liquid, its It is characterised by：

The foaming agent solution is the compound solution containing primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group,

Weak acid and/or the weak acid salting liquid is in weak acid solution, weak acid salting liquid or weak acid/weak acid mixed salt solution One kind,

The Blowing agent composition is 10 with weak acid/salt of weak acid constituent mass ratio:1~1:5000,

In the blowing-agent particle dispersion liquid, the number average bead diameter of blowing-agent particle is 0.1~900 micron,

The step of blowing-agent particle dispersion liquid is mixed with unsaturated acrylic monomer and cross-linking agent aqueous solution,

The step of blowing-agent particle is polymerize with unsaturated acrylic monomer and crosslinking agent mixed solution,

The step of aqueous gel shaped polymer is crushed in the course of the polymerization process or after polymerization,

The step of being thermally dried to the aqueous gel shaped polymer after crushing,

The step of grain refined is carried out to loose structure cross-linked polymer after drying and is sieved,

Surface crosslinking agent processing screening after water-absorbing resins near surface, formed covalent bond the step of,

With cationic compound processing water-absorbing resins surface, the step of forming ionic bond.

1.1 monomer solution

The step of acquisition contains unsaturated acrylic monomer and cross-linking agent aqueous solution.It is specifically described below.

Monomer (monomer) used in the present invention can be formed by radical polymerization and inhaled to contain unsaturated double-bond Monomer of the Mono-olefinic unsaturation containing acid groups of water-base resin, is not particularly limited.It can be listed below：Acrylic acid, methyl Acrylic acid, ethylacrylic acid, α-chloroacrylic acid, alpha-cyanoacrylate, Beta-methyl acrylic acid (crotonic acid), atropic acid, β-acryloxy propionic, sorbic acid, α-chlorine sorbic acid, 2 '-methyl iso-crotonic acid, cinnamic acid, p- chloro-cinnamic acid, β-tristearin Acid, itaconic acid, citraconic acid, mesaconic acid, glutaconate, aconic acid, maleic acid, cinnamic acid, fumaric acid, tricarboxylic ethene and maleic acid Acid anhydride, most preferably particularly preferred acrylic acid and methacrylic acid, acrylic acid.

It can be copolymerized using other class monomers with the monomer containing carboxyl.It can be listed below：Vinyl sulfonic acid, alkene Propyltoluene sulfonic acid, vinyl toluene sulfonic acid, styrene sulfonic acid, 2- (methyl) acrylamide-2-methyl propane sulfonic, 2- (methyl) The anionic properties such as acryloyl group ethyl sulfonic acid, 2- (methyl) acryloyl groups propane sulfonic acid, (methyl) acryloyl group phosphoric acid 2- hydroxy methacrylates Unsaturated monomer and its salt；Unsaturated monomer containing sulfydryl；The unsaturated monomer of phenolic hydroxy group；(methyl) acrylamide, N- second The unsaturated monomer of the amide-containing such as base (methyl) acrylamide, N, N- dimethyl (methyl) acrylamide；(methyl) acrylic acid N, N- dimethyl amido ethyl ester, (methyl) acrylic acid N, N- dimethyl amido propyl ester, N, N- Dimethylaminopropyls (methyl) third Unsaturated monomer containing amino such as acrylamide etc..

These unsaturated monomers can be used alone, and can also be mixed with two or more, comprehensive absorbent resin powder It is preferable to use contain acrylic acid and/or its salt (such as sodium salt, lithium salts, sylvite, ammonium salt, amine etc. for performance and cost Salt), wherein in terms of the cost, the more preferably polyacrylic acid water-absorbent resin of the acrylic monomer of sodium salt.

There is no particular restriction for the neutralization ratio of these undersaturated monomers containing acid groups, can be in part and/or complete Neutralize, preferably part neutralizes, and can also optionally neutralize polymeric gel after polymerisation.The unsaturation contains acid groups The preferred degree of neutralization of monomer is 25~100ml%, particularly preferably reaches at least 40~95ml%, more preferably up to 50~90ml%. The neutralization of the unsaturated monomer containing acid groups can be carried out before the polymerization or afterwards.Can use alkali metal hydroxide, Alkaline earth metal hydroxide, ammonia and carbonate and bicarbonate are neutralized.In addition it is possible to use any other can be with institute State the alkali that acid forms water soluble salt.It can also be neutralized using a variety of alkali.It is preferred that neutralized using ammonia or alkali metal hydroxide, Particularly preferably neutralized using sodium hydroxide.

As polyacrylic absorbent resin powder, the usage amount of acrylic acid and/or its salt relative to whole monomers into Divide (except crosslinking agent), usually more than 60ml%, preferably more than 75ml%, preferably more than 90ml%, further preferably For more than 95ml%.

Monomer concentration is also not particularly limited, and the unsaturated monomer containing acid groups and cross-linking agent aqueous solution concentration is 25~ 60wt%, preferably 30~55wt%, further preferred 35~50wt%.In the case of monomer concentration is less than 25wt%, energy is produced Power can reduce, therefore not good enough.In the case of monomer concentration is higher than 60wt%, load increase is crushed, causes production stability to be deteriorated. The solvent of monomer is water, can also and with a small amount of organic solvent.

As internal crosslinker, the compound for containing multiple vinyl selected from intramolecular, intramolecular contain at least one ethene Based compound and it is at least one can have with the compound of the functional group of carboxyl reaction, intramolecular on the unsaturated monomer it is multiple Can be with the one or more in the compound of the functional group of carboxyl reaction on the unsaturated monomer.Previously many institute's weeks can be used The internal crosslinking agent known.Specifically, such as can enumerate：N, N '-methylene-bisacrylamide, trimethylolpropane tris (first Base) acrylate, ethylene glycol two (methyl) acrylate, polyethyleneglycol diacrylate, polyethylene glycol two (methyl) acrylic acid Ester, polyethylene glycol diallyl ether, tetramethylol methane tetraacrylate, triarylamine, ethylene glycol diglycidylether, ethylene glycol, 1,2- propane diols, 1,3- propane diols, 1,4- butanediols, glycerine, pentaerythrite, polyethylene glycol and one kind in ethylene carbonate or It is a variety of, these internal crosslinking agents, it is contemplated that reactivity can use one or more.Wherein, preferred trimethylolpropane tris In (methyl) acrylate, polyethyleneglycol diacrylate, ethylene glycol diglycidylether, polyethylene glycol, 1,4- butanediols One or more, further preferred trimethylolpropane tris (methyl) acrylate, polyethyleneglycol diacrylate, ethylene glycol two One or more in glycidol ether.

The usage amount of internal crosslinker determines according to the physical property of required water-absorbing resins, relative to content of monomer, is preferably 0.001~5ml%, more preferably 0.005~2ml%, more preferably 0.01~1ml%.If the usage amount of internal crosslinker Less than 0.001ml%, the water soluble apparent extract increase of gained water-absorbing resins, and the water suction under pressurization can not be substantially ensured that Amount.If the usage amount of internal crosslinking agent is more than 5ml%, chemical crosslinking density is too high, the absorbent resin powder of gained Water absorption deficiency.In addition, internal crosslinking agent once can be added in reaction system, can also be added batch-wise to reaction system In.

1.2 blowing-agent particle dispersion liquids

As foaming agent, it occurs physically and/or chemically to react in the manufacturing process of water-absorbing resins, decomposes to give off gas Body (such as carbon dioxide, oxygen, nitrogen, ammonia etc.), to increase the hole of resin surface.In the present invention, blowing-agent particle point Dispersion liquid passes through foaming agent solution and weak acid and/or salt of weak acid solution mixing system is standby.

The foaming agent solution be containing primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group, can by heat resolve and/or Ultraviolet lighting decomposes the azo-compound solution for producing gas, wherein, the azo-compound is selected from azo diisobutyl imidazoles Quinoline, 2,2 '-azo [2- (2- imidazoline -2- bases) propane], 2,2 '-azo-two (2- methyl) propyl group amidine, 2,2 '-azo [N- (2- ethoxys) -2- methyl-props amidine], diazo aminobenzene, 4- amino -3,2- dimethyl azobenzene, 4- aminoazabenzols and above-mentioned One or more in the hydrochloride or sulfate of compound.

Weak acid (salt) in weak acid and/or the weak acid salting liquid is can be with primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group The organic acid (salt) or inorganic acid (salt) of coordinate bond are formed, the organic acid (salt) or inorganic acid (salt) are selected from acetic acid (salt), third Sour (salt), acrylic acid (salt), lactic acid (salt), glyceric acid (salt), n-butyric acie (salt), isobutyric acid (salt), 3-butenoic acid (salt), isobutyl Olefin(e) acid (salt), positive valeric acid (salt), isovaleric acid (salt), 2- penetenoic acids (salt), 3- penetenoic acids (salt), 4- penetenoic acids (salt), glutamic acid (salt), n-caproic acid (salt), isocaproic acid (salt), benzoic acid (salt), sulfurous acid (salt) are one or more, preferably acetic acid (salt), propionic acid (salt), acrylic acid (salt), 3-butenoic acid (salt), methacrylate (salt), 2- penetenoic acids (salt), 3- penetenoic acids (salt), 4- penetenoic acids (salt) is one or more, further preferred acetic acid (salt).

In the blowing-agent particle dispersion liquid formed, the number average bead diameter of blowing-agent particle is 0.1~900 micron, preferably For 0.5~100 micron, more preferably 1~50 micron.Foaming agent solution and weak acid and/or salt of weak acid solution mixing system are standby In blowing-agent particle dispersion liquid step, it can be carried out under stirring or static conditions.

In order to effectively control the dispersiveness of blowing-agent particle dispersion liquid, solubility and particle diameter, in the dissolving of foaming agent, disperse Or organic solvent can be used in dispersion liquid preparation process, such as can enumerate：Methanol, ethanol, glycerine, acetone, ethyl acetate, Dimethyl sulfoxide, (poly-) ethylene glycol, (poly-) propane diols, ethylene carbonate, ethylene glycol, 1,2- propane diols, 1,3- propane diols, 1,4- fourths Glycol etc..These organic solvents can use one or more.When using organic solvent, consumption of organic solvent is with water quality Meter, is controlled in below 20wt%, preferably below 10wt%, further preferred below 5wt%.Alternatively, it is also possible to pass through addition Dispersant (such as non-dissolving polymer in starch, starch derivatives, cellulose, cellulose derivative, inorganic salts, monomer solution Material etc.), precipitating reagent, the methods of cooling control dispersiveness, solubility and particle diameter of the foaming agent in monomer solution.

1.3 blowing-agent particle monomer solutions

Blowing-agent particle dispersion liquid is mixed with unsaturated acrylic monomer and cross-linking agent aqueous solution, prepares foaming agent Grain monomer solution, foaming agent need to be dispersed in monomer solution under stirring or static condition.

Blowing-agent particle is -10~120 DEG C in temperature, the time is in 1~60 minute, in 100 mass in monomer solution 0~10 mass parts can be dissolved in part monomer solution, are preferably able to the mass parts of dissolving 0~1, it can further preferably dissolve 0~ 0.1 mass parts.Number average bead diameter of the blowing-agent particle in monomer solution be 0.1~900 micron, preferably 0.5~100 micron, More preferably 1~50 micron.

In order to effectively control dispersiveness, solubility and particle diameter of the foaming agent in monomer solution, disperse in blowing-agent particle Organic solvent can be used in liquid and unsaturated monomer and cross-linking agent aqueous solution mixed process, such as can be enumerated：Methanol, second Alcohol, glycerine, acetone, ethyl acetate, dimethyl sulfoxide, (poly-) ethylene glycol, (poly-) propane diols, ethylene carbonate, ethylene glycol, 1,2- third Glycol, 1,3- propane diols, 1,4- butanediols etc..These organic solvents can use one or more.When using organic solvent, Consumption of organic solvent is controlled in below 20wt%, preferably below 10wt%, further preferred below 5wt% with water quality gauge. Alternatively, it is also possible to by adding foaming agent protection materials (such as starch, starch derivatives, cellulose, cellulose derivative, nothing Non- dissolving polymeric material etc. in machine salt, monomer solution), precipitating reagent, the methods of cooling control foaming agent in monomer solution In dispersiveness, solubility and particle diameter.

Above-mentioned blowing-agent particle can discharge gas by chemistry and/or physical reactions, and the generation and release of gas are being set Fat prepare temperature-rise period realize, gas release temperature be 20~200 DEG C, preferably 40~180 DEG C, more preferably 70~ 160 DEG C, when gas release temperature is less than 20 DEG C, gas can not be rested on effectively in polymerization system, it is impossible to reach preferable Pore effect, when gas release temperature be less than 200 DEG C when, gas yield in whole resin manufacturing processes is seldom.

Blowing-agent particle dosage is in terms of 100 parts by weight unsaturated monomers, in the range of 0.005~20 parts by weight, preferably 0.01~10 parts by weight, further preferred 0.02~5 parts by weight, when blowing-agent particle dosage is less than the situation of 0.005 parts by weight When, it is impossible to preferably high rate of liquid aspiration is obtained, when blowing-agent particle dosage is higher than 20 parts by weight, resin property deterioration is raw Dust is serious during production, transport and use, and impact resistance declines, and production cost is higher.

Blowing-agent particle dispersion liquid before prepared by unsaturated acrylic monomer and cross-linking agent aqueous solution, in preparation process or Monomer solution is dispersed to after preparation.In addition, blowing-agent particle dispersion liquid is before initiator adds monomer solution, in adition process Or it is added to after adding in solution.

1.4 polymerization procedure

Polymerization procedure is the step of monomer solution is polymerize.Polymerization process can be entered under normal pressure, decompression or pressurization OK, preferably carry out at ambient pressure.

As the polymerization initiator used in this step, there is no particular restriction, can use and under polymerization conditions can Form free radical and be commonly used for preparing any initiator of water-absorbing resins.Can also be by acting on and can gather electron beam The water-containing monomer solution of conjunction and trigger polymerization.It can also be acted on by high-energy radiation in the presence of photoinitiators poly- to trigger Close.According to monomeric species, the polymerizing condition etc. being polymerize, from usual manufacture water-absorbing resins when the polymerization initiator that is utilized in Selection is one or more to be used.

Polymerization initiator is preferably peroxide, hydroperoxides, hydrogen peroxide, persulfate and azo-compound.It is excellent Choosing uses water soluble starter.Specifically enumerate：Heat decomposition type initiator, such as sodium peroxydisulfate, potassium peroxydisulfate, ammonium persulfate over cure Hydrochlorate；The peroxide such as hydrogen peroxide, tert-butyl peroxide, methyl ethyl ketone peroxide, azonitrile compound, azo amidine chemical combination Double (2- amidine propanes) disalts of thing, ring-type azo amidine compound, azo amide compound, alkyl azo-compound, 2,2 '-azo The azo-compounds such as double [2- (2- imidazoline -2- bases) propane] dihydrochlorides of hydrochlorate, 2,2 '-azo；Or light breakdown type initiator, Such as Benzoin derivative, benzil derivatives, acetophenone derivs, benzophenone derivates, azo-compound.These trigger In agent, for regard to cost and reducing the ability of residual monomer, preferably heat decomposition type initiator, more preferably persulfuric acid Salt.

In addition, the decomposition of these polymerization initiators can be promoted by and with reducing agent.Therefore, it is possible to use redox System initiator.As the reducing agent, it is not particularly limited, can be selected from：Sodium pyrosulfite, sodium sulfite, bisulfite The sulfurous acid such as sodium (hydrogen) (salt), L-AA (salt), metal salt (such as iron (II) ion or silver ion), amine etc..In oxygen In the case that change reduction series initiators so use oxidative polymerization initiator and reducing agent, it can be closed respectively with monomer solution Reducing agent, can also be mixed in monomer solution by stream in advance.

When carrying out the polymerization, poly- second two can also be added in reaction system before polymerization or in polymerization as needed Alcohol, starch, starch derivatives, cellulose, cellulose derivative, polyvinyl alcohol, polyacrylic acid (salt), polyacrylic acid (salt) crosslinking The hydrophilic polymers such as body；Or chain-transferring agent, the chelating agent such as ortho phosphorous acid (salt) etc.., can be preferable as hydrophilic macromolecule Ground uses water-soluble resin or water-absorbing resins, can improve the viscosity of reaction system.Relative to monomer, hydrophilic polymer Usage amount is preferably 0~30wt%, more preferably 0.001~20wt%, more preferably 0.01~10wt%.

As the polymerization employed in this step, it is not particularly limited.Radical polymerization in preferably homogeneous (such as radical polymerization in the aqueous solution), the precipitation polymerization from organic solvent, suspension polymerisation, emulsion polymerization or mini-emulsion polymerization Deng.It is preferred that the free radical polyalcohol in homogeneous system, the radical polymerization in the further preferred aqueous solution.Water solution polymerization process has Make the standing polymerization that monomer solution is polymerize under static condition and the stirring polymerization being polymerize in agitating device Method etc..In addition, polymerization is divided into batch method according to continuous production and continuity method polymerize.It is particularly suitable for the polymerization solved the problems, such as It is aqueous solution polymerization, especially continuous conveyor polymerization or continuous kneader polymerization.

As the manufacture device of the water-absorbing resins of the present invention, it is not particularly limited, preferably continuous conveyor polymerization dress Put or continuously stir polyplant.

Continuous conveyor polyplant is preferably the continuous standing polyplant of ring-type conveyer belt type, and conveyer belt is fluororesin System or the conveyer belt to be formed with fluororesin-coated surface.Furthermore it is preferred that to possess heater or attemperator, and have By the device of the steam of caused water and/or monomer solution when polymerizeing is reclaimed and is recycled system.

Single shaft agitating device can be used by continuously stirring polyplant, continuous kneader etc. can also be used to have multiple stir The agitating device of axle is mixed, for productive viewpoint, preferably using multi-shaft stirring device.

When polymerization start temperature refers to that initiator adds to monomer solution, the real time temperature of polymerization system.The monomer is water-soluble In the step of liquid is polymerize, in order to solve the problems, such as in the invention and promote the progress of foaming process, polymerization start temperature is 20~120 DEG C, preferably 40~110 DEG C, more preferably 60~100 DEG C.If polymerizeing start temperature is less than 20 DEG C, polymerization Time is grown, and production capacity is greatly reduced, and the physical property of water-absorbing resins may also reduce.If polymerizeing start temperature is higher than 120 DEG C, then there is the worry that the physical property of water-absorbing resins reduces.It is not particularly limited for polymerization time, according to monomer and polymerization initiator Species, polymerization temperature etc. is appropriate determines, but in terms of the production capacity for, polymerization time is more short better.

In addition, in order to promote to foam, preferably make peak temperature during polymerization higher, peak temperature is excellent in polymerization procedure Elect more than 100 DEG C, more preferably 100~170 DEG C, more preferably 100~150 DEG C as.

1.5 pulverising step

The step of aqueous gel shape cross-linked polymer of above-mentioned gained is crushed, pulverising step can polymerization when or Carried out after polymerization.Crushing process during polymerization can use kneader, and the crushing after polymerization can use cutting machine, meat grinder Deng.Preferably 0.5~10 millimeter of gel particle size after crushing, if gel particle is too small, the higher wind of level of residual monomers can be brought Danger, if water-setting gum polymers are not crushed or gel particle is too big, final granular product can not be obtained, especially In subsequent heat drying steps, it is difficult to evaporate the moisture in hydrogel.

1.6 heat-drying step

Heat-drying step is that the aqueous gel shape cross-linked polymer is subject into drying, forms loose structure and dries polymerization Thing.Dry generally in 60~300 DEG C as heating medium temperature, preferably 100~250 DEG C, more preferably 120~220 DEG C of temperature Degree is lower to be carried out.Drying time depends on the water content and drier type of surface area and polymer, is selected to obtain target Water content (water content passes through in 105 DEG C of dry 3 hours weightless measurements).

Water content for water-absorbing resin of the present invention is not particularly limited, water content more preferably 0.2~30wt%, further It is preferred that 0.3~15wt%, particularly preferred 0.5~10wt%.Too high-moisture not only damages mobility, and therefore influences production, And make being crushed into for water-absorbing resin can not possibly and may be out of hand to specific size distribution.

It is not particularly limited as used drying means, a variety of methods can be used to obtain target water content, specifically Enumerate：Heat drying, hot-air are dry, be dried under reduced pressure, infrared drying, microwave drying, by with hydrophobic organic solvent Azeotropic mixture is dehydrated and dried using high-temperature steam high humility.

In addition, foaming agent can pass through further thermal decomposition under the drying temperature, further foaming process is realized.

1.7 grain refineds and screening step

In order to obtain the water-absorbing resins (adjusting particle diameter jointly with following micro mist granulation process) with specified particle size, it is necessary to The step of grain refined is carried out to loose structure cross-linked polymer after drying and is sieved.

For obtaining having irregular pulverized shape, and the absorbent resin that particle diameter can be controlled effectively, grain refined use Machine include shearing rough pulverizer, impact powder pulverizer and high-speed rotation type powder pulverizer.It is and right after grain refined Resin particle is further sieved.

The Mass median diameter (D50) of water-absorbing resins, is preferably regulated as 200~650 microns, is more preferably adjusted to 200 ~550 microns, further preferably it is adjusted to 300~500 microns.Particle fraction control of the diameter less than 150 microns for 0~ 8wt%, preferably 0~5wt%, more preferably 0~2wt%.In addition, diameter is more few better higher than 850 microns of particle fraction, control For 0~8wt%, preferably 0~5wt%, more preferably 0~2wt%.In the present invention, it is preferred in 150~850 microns of particle Ratio carries out surface-crosslinked under conditions of being more than 95wt%, more preferably more than 98wt%.The logarithmic scale of size distribution is inclined Poor (σ ζ) is preferably controlled to 0.20~0.40, more preferably 0.20~0.38, and further preferred 0.20~0.36.

The recycling of 1.8 fine grained water-absorbing resins

In the present invention, small particle fine grained is controlled (to be less than 150 by the way that fine grained water-absorbing resins are recycled The particle of micron) yield.

The small particle water absorbing resin particle (particle for being less than 106 microns) obtained by grain refined and screening can pass through return Polymerize again to monomer solution or mixed with a large amount of hot water carry out agglomeration (weight of little particle water-absorbing resin and hot water ratio be 2: 1~1:2), to revert to water-setting gum-like product again.Then by being granulated, dry and the step such as grain refined is readjusted as mesh Mark particle diameter water absorbing resin particle.Amount of waste can be reduced by the particle for reclaiming and regenerating beyond target zone.

It is 1.9 surface-crosslinked

In the manufacture method of the present invention, also including the use of surface crosslinking agent to the water-absorbing resins surface after Sieving and casing Nearby carry out the step of surface treatment forms covalent bond.By carrying out surface-crosslinked step to the water-absorbing resins after Sieving and casing Suddenly, the water absorbent rate and permeability for liquids under resin pressurization can effectively be lifted.But for the present invention water-absorbing resin from Heart water holding capacity (CRC), compared to having and reducing to a certain degree before crosslinking, is original centrifuge retention capacity after surface-crosslinked 50~95%, it is further reduced to 60~90%.The reduction degree of centrifuge retention capacity can by the type and dosage of crosslinking agent, Reaction temperature and time adjustment.

The surface-crosslinked processing of the present invention means to increase the operation of crosslink density near particle surface.More specifically Say, it is that have at least two can be formed with the compound of the functional group of carboxyl reaction by being added in particle surface in molecule The operation of new crosslinking, the compound can be by forming key with the carboxyl included in particulate water-absorbing resin or its reactant salt Close.The surface crosslinking agent that this step uses, it is preferably able to form covalent bond or ionic bond with water-absorbing resins surface functional group Surface crosslinking agent.

As the surface crosslinking agent that can be used in this step, preferably for example：It is polyol compound, epoxide, more Amines or with the condensation product, oxazoline compounds of its halogenated epoxy compound, (mono-, di- or poly-) oxazoles pyridine assimilation compound, Carbonic acid alkane diester compound.Specifically include：Polyalcohol such as polyethylene glycol, 1,2- propane diols, 1,3- propane diols, a contracting dipropyl two Alcohol, 2,3,4- trimethyl -1,3- pentanediols, polypropylene glycol, glycerine, polyglycereol, 2- butylene-1,4-diols, 1,4- butanediols, 1, 3- butanediols, 1,5- pentanediols, 1,6-HD, 1,2- cyclohexanedimethanols etc.；Epoxide such as ethylene glycol two shrinks sweet Oily ether, Polyethylene Glycol Bisglycidyl Ether, glycidol etc.；Multivalence amines such as ethylenediamine, diethylenetriamines, triethylene Tetramine, tetren, penten, polyethyleneimine etc.；Halogenated epoxide such as epoxychloropropane, epoxy bromine Propane, Alpha-Methyl epoxychloropropane etc.；The condensation product of multivalence amines and halogenated epoxide；Oxazolidinone compounds example Such as 2- oxazolidones；Ring urea；Alkylene carbonate compound is such as ethylene carbonate.They can be used alone or a variety of It is used in combination.To give full play to the effect of the present invention, preferably it is combined using polyol compound and epoxide.As polynary Alcohol, the preferably polyalcohol with 2~10 carbon atoms, the further preferably polyalcohol with 3~8 carbon atoms.

The dosage of surface crosslinking agent depends on using type of crosslinking agent and its combination, is preferably based on water-absorbing resin 0.01 ~10wt%, more preferably 0.05~5wt%.

In the present invention is surface-crosslinked, the solvent of surface crosslinking agent preferably uses water.The dosage of water depends on surface-crosslinked The water content of agent effective ingredient consumption and water-absorbing resin, is preferably based on 0.2~20wt% of water-absorbing resin, more preferably 0.3~ 15wt%, further preferred 0.5~10wt%.In addition, hydrophilic organic solvent can be used to be used in mixed way with water, when using hydrophilic During property organic solvent, preferable organic solvent dosage is based on 0~10wt% of water-absorbing resin, more preferably 0~8wt%, and further preferred 0 ~5wt%.

It is preferred that surface crosslinking agent is pre-mixed in water and/or hydrophilic organic solvent, then to by treatment fluid spraying or It is added dropwise to water-absorbing resin, more preferably spray method.The mean droplet size of the spraying is preferably 0.1~500 micron, more preferably 0.1~200 micron.

After surface crosslinking agent is added into water-absorbing resin, preferred pair its be heat-treated.It is 100~220 to be surface-treated temperature DEG C, preferably 130~210 DEG C, further preferred 160~200 DEG C, the heat time is preferably 1 minute~2 hours.

1.10 chelating agent

By adding chelating agent, the time course point derived from component in urine with the water absorbing agent of Fe ionic reactions can be suppressed Solution, can equally suppress the dissolving of water absorbing agent, reduce the absorptivity of water absorbing agent, reduce the permeability for liquids of water absorbing agent.Chelating agent exists Following one or more times add：(1) during polymerization；(2) after polymerisation with it is surface-crosslinked before；(3) on surface During crosslinking；(4) during agglomeration.

Chelating agent for water absorbing agent of the present invention is preferably to have high sealing ability or sequestering power to Fe or Cu ions Chelating agent, preferably amino polyvalent carboxylic acid and its salt, particularly preferably there is amino carboxylic acid and its salt no less than 3 carboxyls.

The dosage of amino polyvalent carboxylic acid is 0.00001~10wt%, preferably 0.0001~1wt% based on water-absorbing resin.

1.11 inorganic powder

By adding inorganic powder, the permeability for liquids of water-absorbing resin can be effectively lifted, preferably inorganic powder is average grain SiO 2 powder of the footpath below 100 nanometers.The inorganic powder addition in terms of water-absorbing resins, be 0.001~ 10wt%, preferably 0.005~1wt%, further preferred 0.01~0.5wt%.

1.12 other additives

Other auxiliary agents can be added in water-absorbing resins as needed, including：Oxidant, antioxidant, reducing agent, face The water-insolubles such as colouring stabilizer, water, polyvalent metal compounds, metallic soap are inorganic or organic dust, deodorant, antiseptic, paper pulp Or thermoplastic fibre etc..

[2] physical property of polyacrylic acid water-absorbent resin

The polyacrylic acid water-absorbent resin of the present invention has the particulate water-absorbing agent of irregular pulverized shape, specific physical property It is as follows.

2.1 surface apertures

Water-absorbing resins surface porosity is observed by SEM, in order to effectively lift the suction of resin Liquid speed rate, control the apparent density of resin and improve the impact resistance crushing performance of resin, the loose structure average pore size is preferred For 10~500 microns, more preferably 10~300 microns, more preferably 10~200 microns, especially preferably 10~150 microns.

2.2 centrifuge retention multiplying powers (CRC)

Centrifuge retention multiplying power (CRC) to 0.9wt% sodium-chloride water solution is preferably 10~60g/g, and more preferably 20 ~55g/g, more preferably 25~50g/g, especially preferably 25~45g/g.For absorbability.CRC is the higher the better, But need to be balanced with other physical property as the case may be when actually using.

2.3 pressurization water absorbent rates (AUP)

Water-absorbing resins are carried out surface-crosslinked to lift its water suction to 0.9wt% sodium-chloride water solution under stress Multiplying power (pressurization water absorbent rate, AUP).Under 1.9kPa (0.3psi) pressure, AUP is preferably 15~55g/g, more preferably 15~ 50g/g, more preferably 15~45g/g, especially preferably 15~40g/g.Under 4.8kPa (0.7psi) pressure, AUP is excellent Elect 10~50g/g, more preferably 10~45g/g, more preferably 10~40g/g, especially preferably 10~35g/g as.AUP It is the higher the better, but need to be balanced with other physical property as the case may be during actual use.

2.4 leachable things (Extr)

The solvable apparent extract (Extr) of water-absorbing resins of the present invention is preferably 0~40wt%, more preferably 1~ 30wt%, more preferably 3~25wt%.

2.5 swirl method infiltration rates

The swirl method infiltration rate of water-absorbing resins of the present invention is shorter than 60sec/g, preferably 1~55sec/g, more preferably 10~ 50sec/g.Water absorbing agent of the infiltration rate more than 60sec/g may not reach enough effects.

2.6 apparent density

Apparent density represents the quality accumulated after the powder freely falling body of unit volume.Water-absorbing resins of the present invention it is apparent Density is 0.50~0.80g/cm³, preferably 0.51~0.75g/cm³, more preferably 0.52~0.70g/cm³。

2.7 particle sizes and distribution

The median granularity of quality (D50) of water-absorbing resins of the present invention, is preferably regulated as 200~650 microns, more preferably adjusts For 200~550 microns, 300~500 microns are further preferably adjusted to.Particle fraction control of the diameter less than 150 microns is 0 ~8wt%, preferably 0~5wt%, more preferably 0~2wt%.In addition, diameter is more few better higher than 850 microns of particle fraction, control It is made as 0~8wt%, preferably 0~5wt%, more preferably 0~2wt%.In the present invention, it is preferred in 150~850 microns of particle Ratio be more than 95wt%, more preferably carry out under conditions of more than 98wt% it is surface-crosslinked.The logarithmic scale of size distribution Deviation (σ ζ) is preferably controlled to 0.20~0.40, more preferably 0.20~0.38, and further preferred 0.20~0.36.

2.8 water content

Water content is to determine the parameter of the volatile materials such as water included in water-absorbing resins.Water imbibition tree of the present invention The water content of fat is preferably 1~10wt%, more preferably 2~10wt%.

2.9 levels of residual monomers

The levels of residual monomers of water-absorbing resins of the present invention is preferably 0~600ppm, more preferably 0~500ppm.

[3] purposes of polyacrylic acid water-absorbent resin

The application of particle-shape water-absorbing resin of the present invention is not particularly limited, and be can be used for paper diaper, physiological hygiene cotton, is lost Prohibit the absorbent commodities such as protection pad, be preferred for for example thin absorbing articles of thin absorption base and absorbing articles.

In absorbent commodity, typically contain other absorbent materials (paper pulp fiber etc.), wherein water-absorbing resins contain Measure as 30~100wt%, preferably 40~100wt%, more preferably 50~100wt%, more preferably 60~ 100wt%.

[4] embodiment

The present invention will be illustrated with following examples and comparing embodiment, but the invention is not restricted to following examples.

The various performances of water-absorbing resins measure through following methods.It is outer unless specified otherwise, water-absorbing resin, water absorbing agent and absorption Article uses under conditions of 25 ± 2 DEG C and 50%RH (relative humidity).Used normal saline solution is 0.90wt% chlorine Change sodium water solution.

4.1 surface apertures

Water-absorbing resins surface porosity and aperture are observed by SEM, by particle-shape water-absorbing Resin sample is adhered on sample stage, is tested after metal spraying.

4.2 centrifuge retention multiplying powers (CRC)

Centrifuge retention multiplying power (CRC) is represented under without pressurization to 0.90wt% sodium-chloride water solutions (also referred to as physiological saline Water) water absorbent rate that is centrifuged after water suction 30 minutes.

0.20 gram of water-absorbing resins is weighed, record weight is W₀(g) it uniformly, is put into the cloth made of supatex fabric In bag, sealing, immerse in normal saline solution of the control at 25 ± 2 DEG C.After 30 minutes by the bag containing water-absorbing resins from Taken out in saline solution.It is dehydrated 3 minutes under 250G using centrifuge, then weighs to obtain weight W₂(g).Without using any The weight W of bag is measured after the similar operations of water absorbing agent₁(g).Centrifuge retention multiplying power (g/g) is calculated according to the following formula.

Centrifuge retention multiplying power (g/g)=((W₂(g)-W₁(g))/W₀(g))-1

4.3 pressurization water absorbent rates (AUP)

Load weighted sample is laid on screen pack, covers the bottom of a special cylinder, begins to use uniform pressure Power (1.9kPa/0.3psi) is applied in test sample, and then cylinder is placed in a culture dish filled with sodium chloride solution. After sample absorbs 1 hour, cylinder is taken out, test absorbs amount of liquid, specific as follows：

0.900g water-absorbing resins are weighed, record weight is W₃(g), it is laid in dry plexiglass cylinder filter screen On, it is uniformly distributed it.Piston is placed on cylinder, and weighs the weight of a whole set of cylinder, is recorded as W₄(g).Filter plate is put Put in culture dish, 120 ml NaCls are added, so that liquid surface floods surface of aluminum plate.Circular filter paper is put into filter On plate, with sodium chloride solution complete wetting, surface is avoided to have bubble generation.A whole set of drum equipment is placed on to the filter soaked On paper, after placing 1 hour, sample is allowed to fully absorb sodium chloride solution.Lift complete equipment and remove its piston, weigh circle again Cylinder device, it is recorded as W₅(g).Pressurization water absorbent rate (AUP) is calculated according to the following formula.

Pressurize water absorbent rate (g/g)=(W₅(g)-W₄(g))/W₃(g)

4.4 solvable apparent extracts (Extr)

Prepare a testing sample for being used to test.200 ml NaCls are accurately added with graduated cylinder and are transferred to one In 250 milliliters of conical flask or beaker, added with magnetic stir bar.1.000 grams of water-absorbing resins accurately are weighed, are accurate to 0.001 Gram, record weight.Dissolved with sodium chloride solution, it is to be ensured that all samples all shift totally.Taper bottle stopper is capped, uses electromagnetism Agitator stirs 16 hours in 500 ± 50r/min rotating speeds.Prepare one 200 milliliters of sodium chloride solution to do relative to sample one The titration blank of batten part.Stop stirring after 16 hours, and deposit gel.Supernatant is filtered out with the Buchner funnel with filter paper Liquid, and collect the liquid no less than 50 milliliters.Standard NaOH solution is added with one 50 milliliters of burets, titrates 50 milliliters of blank Sodium chloride solution, pH value is titrated to as 10.0, then proceed to be titrated to pH with standard hydrochloric acid solution that to be that 2.7. is recorded each The standard NaOH or the volume of HCI agent that individual terminal needs.Standard NaOH solution is added with buret, titrates 50 milliliters Sample Filtrate solutions, it is 10.0 to be titrated to pH value, and it is that 2.7. records each end to then proceed to be titrated to pH with standard HCl solution The volume for standard NaOH or the HCl titrant that point needs.

Carboxylic acid total amount (such as polycarboxylic acids), n in supernatant_COOH, represented with ml concentration, provided by equation (1),

n_COOH=(V_NaOH, s-V_{NaOH, b})c_NaOH (1)

In formula,

V_NaOH,s----volume, ml, the sample supernatant filtered out, which is titrated to when pH is 10.0, with standard NaOH solution needs Volume；

V_NaOH,b----volume, ml, NaOH solution blank solution, which is titrated to when pH is 10.0, with standard NaOH solution needs Volume；

c_NaOH----concentration, mol/l, do the titrant concentration for being titrated to the NaOH solution that pH is 10.0.

The total amount of carboxylate (ester), n in supernatant_tot, represented with ml, provided by equation (2),

n_tot=(V_{HCl, s}-V_{HCl, b})c_HCl (2)

In formula,

V_HCl,s----volume, ml, HCl volumes sample Filtrate solutions being titrated to from pH 10.0 required for 2.7

V_HCl,b----volume, ml, HCl volumes sodium chloride blank solution being titrated to from pH 10.0 required for 2.7

c_HCl----concentration, mol/l, do the concentration that titrant titrates pH HCl solutions used in from 10.0 to 2.7

The carboxylic acid total amount neutralized in supernatant, n_COONa, represented with ml, provided by equation (3)

n_COONa=n_tot-n_COOH (3)

The relative mass of carboxylic acid, m_COOH, represented with g, the relative mass of carboxylic acid sodium, m_COONa, represented with g

Represented respectively with formula (4) and formula (5),

m_COOH=n_COOH×M_COOH×F_dil (4)

m_COONa=n_COONa×M_COONa×F_dil (5)

In formula,

M_COOHThe ml mass of ----acrylic acid, equal to 72g/mol

M_COONaThe ml mass of ----PAA, equal to 94g/mol

F_dil----dilution shadow, equal to 200/50=4

Extractable in super absorbent polymer, w, represented with mass fraction percentage, provided with formula (6),

In formula,

m_s----quality, g, the weight of testing sample

4.5 swirl method infiltration rates

In 100 milliliters of beakers with stirrer, 50 ml NaCls are added with pipette, beaker is placed on magnetic On power agitator, stirred with 500 ± 50r/min rotating speeds, confirm that liquid level produces stable whirlpool.Accurately weigh 2.000 grams of water imbibitions Resin is added in whirlpool, while starts timing with stopwatch, when liquid surface vortex disappear, when liquid level turns into horizontality, as Terminal, record the time.

4.6 apparent density

Representative sample is flowed into density cup to test by the test of water-absorbing resins apparent density by specified funnel.

Funnel is placed on iron hoop support, then support is placed into practical pallet, and density cup is positioned over Lou Struggle against below exit normal, adjusting the height of funnel makes above hopper outlet Distance Density cup 40 ± 1 millimeters.Density cup is weighed, is claimed Standard is recorded as m to 0.1 gram_i.100.00 grams of PA water-absorbing resins sample (standard claims to 0.01 gram) is weighed, is put as testing sample In 1 250 milliliters of beaker.The funnel stopple positioned at funnel bottom is closed, pours into testing sample along inner wall of hopper, and avoid There is deposition.Funnel stopple is opened completely, testing sample is all flowed into and is full of density cup.Gently rotate funnel and remove density Cup, practical pallet is poured into by unnecessary sample.With a scraper with flat blade the upper of neat cup is scraped perpendicular to the suitable for reading of cup, level Portion, to remove unnecessary water-absorbing resins sample, gently cup lid stands sample beyond the Great Wall, should be kept away before being transferred to assay balance and weighing Exempt from that any spilling occurs.The density cup for filling sample is weighed, it is m to record its weight₂。

Apparent density (p) calculating formula of water-absorbing resins is as follows：

4.7 particle sizes and distribution

Particle size and distribution are tested by sieve method.A certain amount of high-hydroscopicity powder by it is a series of in order The standard screen of arrangement, it is separated into different grain size atmosphere.To the powder weighing of each particle size range, and report hundred that it accounts for gross weight Divide ratio.

Large face plate and each empty sieve (being accurate to 0.1 gram) weight, and record.In the correct order (850 microns, 600 Micron, 300 microns, 150 microns, 45 microns) sieve is placed to (fine the bottom of, coarse upper) on the oscillator.Claim Taking 100 grams (being accurate to 0.1 gram), sample to be tested is into beaker, m₁.Load weighted sample is poured into uppermost sieve.Press Sifter cap on the indicating cover of manufacturer.Oscillator is sieved by following parameter setting：Oscillation intensity 70 ± 2% is (according to Retsch VE The setting of 1000 oscillators), 1.0 millimeters of amplitude, duration of oscillation 10 minutes.Open electromagnetic shaker, after 10 minutes by each sieve and Pallet is carefully removed and weighed respectively, is accurate to 0.01 gram, m₂.The percentage (w) for calculating every section of sample is as follows：

It is defined as median granularity of quality (D50) corresponding to the particle diameter of R=50% weight.Logstandard deviation (σ ζ) is by following formula Represent, the σ ζ of wherein smaller value mean narrower size distribution.

σ ζ=0.5 × ln (X2/X1)

Wherein, X1 and X2 is respectively the particle diameter of R=84.1% weight and R=15.9% weight

4.8 water content

It is the ratio for representing particulate water-absorbing resin at 180 DEG C shared by volatile ingredient.

The assay method of water content is to carry out as follows.

Weigh about 1 gram of water-absorbing resin (weight W₇[g]) it is placed in measuring cup (weight W₆[g]) in, air-dried in 105 DEG C of nothings 3 hours are stood in dry machine, is subject to drying.Determine total weight (W of dried measuring cup and particulate water-absorbing resin₈[g]), Calculated according to below equation.

Water content [wt%]={ (W₈-W₆-W₇)/W₇}×100。

4.9 levels of residual monomers

1.000 grams of water-absorbing resins are weighed, and record the quality of sample.Load weighted sample is transferred to the beaker of cleaning In.The sodium chloride solution for taking 200 milliliter 0.9% with graduated cylinder is added in beaker.Magnetic stir bar is put into, beaker liquid level is sealed with paraffin Or the mouth of conical flask is sealed with bottle stopper.With 500 ± 50r/min speed stirred samples.Stop stirring after 60 minutes.Stand sample 5 minutes.With 0.45 urn filter filtered sample, HPLC tests are carried out.

Embodiment 1

Use azo two NSC 18620 hydrochloric acid of the high-speed emulsifying machine (rotating speed 6000r/min) by 3.24 grams of concentration for 6.17wt% Acetic acid/sodium acetate (acetic acid/sodium acetate ml ratios are 2.7/7.3) mixing that saline solution and 12.97 grams of concentration are 42.0wt% is molten Liquid is mixed in room temperature, and azo-bis-isobutyrate hydrochloride is 1 with acetic acid/sodium acetate mass ratio:27.23, obtain foaming agent Grain dispersion liquid (particle diameter<45 microns), it is stand-by.Weighing 200 grams of acrylic monomers, 92 grams of deionized waters and 244 grams of concentration successively is 32wt% sodium hydrate aqueous solution is added in the beaker that volume is 2 liters, is stirred stand-by.Then, 4.66 grams of concentration are weighed Added to for 11.3wt% polyethyleneglycol diacrylate (molecular weight 522) in the monomer solution after above-mentioned part neutralizes, stirring Uniformly.After monomer solution is heated into 94 DEG C, it is by blowing-agent particle dispersion liquid and 7.12 grams of concentration simultaneously under agitation 4.0wt% sodium peroxydisulfate solution, which adds to, carries out polymerisation in monomer solution, temperature of reaction system raises rapidly, temperature change For 94~150 DEG C, foaming agent decomposes under the temperature conditionss, obtains loose structure aqueous gel shaped polymer, aperture 50~200 Micron.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, drying temperature be 190 DEG C, the time be 40 minutes, obtain cross linked porous structural polymer (aperture 50~ 200 microns).Grain refined is carried out to porous crosslinked polymeric after drying using broken cooking machine, and sieved, obtains that there is spy Determine the water-absorbent besin particles 1 of particle diameter, its physical parameter is shown in Table 1.

By above-mentioned 100 parts by weight water-absorbent besin particles and 0.736 parts by weight include 1,2- propane diols, 1,4- butanediols, (weight ratio is 12.4 for ethylene glycol diglycidylether and water:7.4:0.9:79.3) blending surface cross-linking agent solution is mixed Close, and surface treatment 50 minutes is carried out at 165 DEG C, obtain water-absorbing resins 1, its physical parameter is shown in Table 1.

By above-mentioned 100 parts by weight water-absorbing resins respectively with 1.317 parts by weight concentration be 10.3wt% aluminum sulfate solution And 0.184 parts by weight of silica (particle diameter is less than 100 nanometers) powder is mixed, and obtains water absorbency resin composition 1, its thing Property parameter is shown in Table 1.

Table 1

Embodiment 2

Use mechanical agitation mode by 3.24 grams of concentration for 6.17wt% the azo-bis-isobutyrate hydrochloride aqueous solution and Acetic acid/sodium acetate (acetic acid/sodium acetate ml ratios are 2.7/7.3) mixed solution that 12.97 grams of concentration are 42.0wt% enters in room temperature Row mixing, azo-bis-isobutyrate hydrochloride are 1 with acetic acid/sodium acetate mass ratio:27.23, obtain blowing-agent particle dispersion liquid (grain Footpath<45 microns), it is stand-by.The hydrogen-oxygen that 200 grams of acrylic monomers, 92 grams of deionized waters and 244 grams of concentration are 32wt% is weighed successively Change sodium water solution to add in the beaker that volume is 2 liters, stir stand-by.Then, it is 11.3wt%'s to weigh 4.66 grams of concentration Polyethyleneglycol diacrylate (molecular weight 522) is added in the monomer solution after above-mentioned part neutralizes, and is stirred.Monomer is molten After liquid is heated to 94 DEG C, the over cure for being simultaneously under agitation 4.0wt% by blowing-agent particle dispersion liquid and 7.12 grams of concentration Acid sodium solution, which adds to, carries out polymerisation in monomer solution, temperature of reaction system raises rapidly, and temperature change is 94~150 DEG C, Foaming agent decomposes under the temperature conditionss, obtains loose structure aqueous gel shaped polymer, 50~200 microns of aperture.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, drying temperature be 190 DEG C, the time be 40 minutes, obtain cross linked porous structural polymer (aperture 50~ 200 microns).Grain refined is carried out to porous crosslinked polymeric after drying using broken cooking machine, and sieved, obtaining particle diameter is 300~425 microns, CRC 43.4g/g, swirl method infiltration rate be 43sec/g particulate porous structure water-absorbing resins, Aperture is 50~200 microns.

Embodiment 3

Use mechanical agitation mode by 3.24 grams of concentration for 6.17wt% the azo-bis-isobutyrate hydrochloride aqueous solution and Acetic acid/sodium acetate (acetic acid/sodium acetate ml ratios are 2.7/7.3) mixed solution that 12.97 grams of concentration are 42.0wt% enters in room temperature After row is well mixed, by solution left standstill, azo-bis-isobutyrate hydrochloride is 1 with acetic acid/sodium acetate mass ratio:27.23 sent out Infusion particle dispersion (particle diameter<45 microns), other processes are same as Example 2.It is 300~425 microns, CRC to obtain particle diameter The particulate porous structure water-absorbing resins for being 41sec/g for 43.5g/g, swirl method infiltration rate, aperture are 50~200 micro- Rice.

Embodiment 4

Use azo two NSC 18620 hydrochloric acid of the high-speed emulsifying machine (rotating speed 6000r/min) by 3.24 grams of concentration for 6.17wt% The acrylic acid/sodium acrylate that saline solution and 3.24 grams of concentration are 42.9wt% (acrylic acid/sodium acrylate ml ratios are 3.0/7.0) Mixed solution is mixed in room temperature, and the mass ratio of azo-bis-isobutyrate hydrochloride and acrylic acid/sodium acrylate is 1:6.95 obtain To blowing-agent particle dispersion liquid (particle diameter<45 microns), it is stand-by.198.8 grams of acrylic monomers, 91.4 grams of deionized waters are weighed successively The sodium hydrate aqueous solution for being 32wt% with 242.5 grams of concentration is added in the beaker that volume is 2 liters, is stirred stand-by.Then, Weigh the polyethyleneglycol diacrylate (molecular weight 522) that 4.66 grams of concentration are 11.3wt% and add to the list after above-mentioned part neutralizes In liquid solution, stir.After monomer solution is heated into 94 DEG C, under agitation simultaneously by blowing-agent particle dispersion liquid and The sodium peroxydisulfate solution that 7.12 grams of concentration are 4.0wt%, which adds to, carries out polymerisation in monomer solution, temperature of reaction system is rapid Rise, temperature change are 94~150 DEG C, and foaming agent decomposes under the temperature conditionss, obtain the polymerization of loose structure aqueous gel shape Thing, 50~200 microns of aperture.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, drying temperature be 190 DEG C, the time be 40 minutes, obtain cross linked porous structural polymer (aperture 50~ 200 microns).Grain refined is carried out to porous crosslinked polymeric after drying using broken cooking machine, and sieved, obtaining particle diameter is 300~425 microns, CRC 42.8g/g, swirl method infiltration rate be 42sec/g particulate porous structure water-absorbing resins, 50~200 microns of aperture.

Embodiment 5

Use azo two NSC 18620 hydrochloric acid of the high-speed emulsifying machine (rotating speed 6000r/min) by 3.24 grams of concentration for 6.17wt% (acrylic acid/sodium acrylate ml ratios are 3.0/ to the acrylic acid/sodium acrylate that saline solution and 25.92 grams of concentration are 42.9wt% 7.0) mixed solution is mixed in room temperature, and the mass ratio of azo-bis-isobutyrate hydrochloride and acrylic acid/sodium acrylate is 1: 55.62, obtain blowing-agent particle dispersion liquid (particle diameter<45 microns), it is stand-by.Weigh successively 190.3 grams of acrylic monomers, 87.6 grams The sodium hydrate aqueous solution that deionized water and 232.2 grams of concentration are 32wt% is added in the beaker that volume is 2 liters, is stirred and is treated With.Then, the polyethyleneglycol diacrylate (molecular weight 522) that 4.66 grams of concentration are 11.3wt% is weighed to add in above-mentioned part In monomer solution with after, stir.After monomer solution is heated into 94 DEG C, under agitation simultaneously by blowing-agent particle The sodium peroxydisulfate solution that dispersion liquid and 7.12 grams of concentration are 4.0wt%, which adds to, carries out polymerisation, reaction system in monomer solution Temperature raises rapidly, and temperature change is 94~150 DEG C, and foaming agent decomposes under the temperature conditionss, obtains loose structure and contains water-setting Gum polymers, 50~200 microns of aperture.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, drying temperature be 190 DEG C, the time be 40 minutes, obtain cross linked porous structural polymer (aperture 50~ 200 microns).Grain refined is carried out to porous crosslinked polymeric after drying using broken cooking machine, and sieved, obtaining particle diameter is 300~425 microns, CRC 45.2g/g, swirl method infiltration rate be 43sec/g particulate porous structure water-absorbing resins, 50~200 microns of aperture.

Embodiment 6

Use mechanical agitation by 3.24 grams of concentration for the 6.17wt% azo-bis-isobutyrate hydrochloride aqueous solution and 6.48 grams Acrylic acid/sodium acrylate (acrylic acid/sodium acrylate ml ratios are 3.0/7.0) mixed solution that concentration is 42.9wt% enters in room temperature The mass ratio of row mixing, azo-bis-isobutyrate hydrochloride and acrylic acid/sodium acrylate is 1:13.9 (particle diameter<45 microns), obtain Blowing-agent particle dispersion liquid, it is stand-by.Weighing 197.6 grams of acrylic monomers, 90.8 grams of deionized waters and 241 grams of concentration successively is 32wt% sodium hydrate aqueous solution is added in the beaker that volume is 2 liters, is stirred stand-by.Then, 3.94 grams of concentration are weighed Added to for 11.3wt% polyethyleneglycol diacrylate (molecular weight 522) in the monomer solution after above-mentioned part neutralizes, stirring Uniformly.After monomer solution is heated into 94 DEG C, it is by blowing-agent particle dispersion liquid and 7.12 grams of concentration simultaneously under agitation 4.0wt% sodium peroxydisulfate solution, which adds to, carries out polymerisation in monomer solution, temperature of reaction system raises rapidly, temperature change For 94~150 DEG C, foaming agent decomposes under the temperature conditionss, obtains loose structure aqueous gel shaped polymer, aperture 50~200 Micron.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, drying temperature be 190 DEG C, the time be 40 minutes, obtain cross linked porous structural polymer (aperture 50~ 200 microns).Grain refined is carried out to porous crosslinked polymeric after drying, and sieved, obtains the water imbibition with specified particle diameter Resin particle 2, its physical parameter are shown in Table 2.

100 parts by weight water-absorbent besin particles and 0.736 parts by weight are included into 1,2- propane diols, 1,4- butanediols, second two (weight ratio is 12.4 for alcohol diglycidyl ether and water:7.4:0.9:79.3) blending surface cross-linking agent solution is mixed, and Surface treatment 50 minutes is carried out at 165 DEG C, obtains water-absorbing resins 2, its physical parameter is shown in Table 2.

By above-mentioned 100 parts by weight water-absorbing resins respectively with 1.317 parts by weight concentration be 10.3wt% aluminum sulfate solution And 0.184 parts by weight of silica (particle diameter is less than 100 nanometers) powder is mixed, and obtains water absorbency resin composition 2, its thing Property parameter is shown in Table 2.

Table 2

Comparative example 1

It is water-soluble that the sodium hydroxide that 200 grams of acrylic monomers, 92 grams of deionized waters and 244 grams of concentration are 32wt% is weighed successively Liquid is added in the beaker that volume is 2 liters, is stirred stand-by.Then, the polyethylene glycol that 4.66 grams of concentration are 11.3wt% is weighed Diacrylate (molecular weight 522) is added in the monomer solution after above-mentioned part neutralizes, and is stirred.Monomer solution is heated to After 94 DEG C, under agitation the sodium peroxydisulfate initiator solution that 7.12 grams of concentration are 4.0wt% is added in monomer solution Row polymerisation, temperature of reaction system raise rapidly, and temperature change is 94~150 DEG C, obtain containing without loose structure is transparent Water-setting gum polymers.

Then, aqueous gel shaped polymer is crushed using meat grinder, makes its particle diameter below 10 millimeters.And to solidifying Glue particle is dried, and drying temperature is 190 DEG C, and the time is 40 minutes.Using broken cooking machine to drying post-crosslinking polymer Grain refined is carried out, and is sieved, acquisition particle diameter is 300~425 microns, CRC 46.2g/g, swirl method infiltration rate are 58sec/g particle-shape water-absorbing resin.

Comparative example 2

Use mechanical agitation mode by 3.24 grams of concentration for 6.17wt% the azo-bis-isobutyrate hydrochloride aqueous solution and Acetic acid/sodium acetate (acetic acid/sodium acetate ml ratios are 3.0/7.0) mixed solution that 12.97 grams of concentration are 42.0wt% enters in room temperature Row mixing, azo-bis-isobutyrate hydrochloride are 1 with acetic acid/sodium acetate mass ratio:27.23, will when not forming blowing-agent particle It is added in monomer solution simultaneously with initiator, and other processes are same as Example 2.Obtain particle diameter be 300~425 microns, The particle-shape water-absorbing resin that CRC is 45.6g/g, swirl method infiltration rate is 55sec/g.

From Tables 1 and 2, by particle size, foaming agent and weak acid/the salt of weak acid component for controlling blowing-agent particle Species and ratio, do not influenceing CRC, 0.3psi AUP, level of residual monomers, and apparent density will not be down to it is too low in the case of, The infiltration rates of water-absorbing resins can be substantially improved to 32sec/g.

Therefore, the invention provides a kind of buildup of resin density excessively to reduce, and does not influence its imbibition characteristic, Ke Yigao The method of water-absorbing resins of the effect ground production with high speed rate of liquid aspiration, and obtain a kind of water imbibition with high speed rate of liquid aspiration Resin.

Embodiments of the invention are these are only, are not intended to limit the scope of the invention, it is every to be said using the present invention The equivalent structure or equivalent flow conversion that bright book content is made, or other related technical fields are directly or indirectly used in, Similarly it is included within the scope of the present invention.

Claims (29)

1. a kind of manufacture method of water-absorbing resins, it is characterised in that it comprises the following steps：

(a) obtain and contain unsaturated acrylic monomer and cross-linking agent aqueous solution,

(b) after foaming agent solution is mixed with weak acid and/or weak acid salting liquid, the step of preparing blowing-agent particle dispersion liquid,

(b1) foaming agent solution is the compound solution containing primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group,

(b2) weak acid and/or the weak acid salting liquid is in weak acid solution, weak acid salting liquid or weak acid/weak acid mixed salt solution One kind,

(b3) Blowing agent composition and the weak acid/salt of weak acid constituent mass ratio are 10:1~1:5000,

(b4) in the blowing-agent particle dispersion liquid, the number average bead diameter of blowing-agent particle is 0.1~900 micron,

(c) the step of blowing-agent particle dispersion liquid being mixed with unsaturated acrylic monomer and cross-linking agent aqueous solution,

(d) blowing-agent particle is polymerize with unsaturated acrylic monomer and crosslinking agent mixed solution.

2. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the unsaturated acrylic monomer The mixed solution for being the water soluble salt of acrylic acid and/or acrylic acid as principal component with the aqueous solution of crosslinking agent.

3. the manufacture method of water-absorbing resins according to claim 2, it is characterised in that the water soluble salt of the acrylic acid is At least one of sodium salt or sylvite.

4. the manufacture method of water-absorbing resins according to claim 1 or claim 2, it is characterised in that the unsaturated acrylic acid series Monomer and cross-linking agent aqueous solution concentration are 25~60wt%, preferably 30~55wt%, further preferred 35~50wt%.

5. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the crosslinking agent contains selected from intramolecular Have the compound of multiple vinyl, intramolecular contain at least one vinyl compound and it is at least one can with it is described unsaturated single On body the compound of the functional group of carboxyl reaction, intramolecular have it is multiple can be with the function of carboxyl reaction on the unsaturated monomer One or more in the compound of group.

6. the manufacture method of water-absorbing resins according to claim 5, it is characterised in that the crosslinking agent is selected from N, N '-Asia Bisacrylamide, trimethylolpropane tris (methyl) acrylate, ethylene glycol two (methyl) acrylate, polyethylene glycol two Acrylate, polyethylene glycol two (methyl) acrylate, polyethylene glycol diallyl ether, tetramethylol methane tetraacrylate, three virtues Base amine, ethylene glycol diglycidylether, ethylene glycol, 1,2- propane diols, 1,3- propane diols, 1,4- butanediols, glycerine, Ji Wusi One or more in alcohol, polyethylene glycol and ethylene carbonate, preferably trimethylolpropane tris (methyl) acrylate, poly- second two One or more in alcohol diacrylate, ethylene glycol diglycidylether, polyethylene glycol, BDO, further preferably Trimethylolpropane tris (methyl) acrylate, polyethyleneglycol diacrylate, one kind in ethylene glycol diglycidylether or It is a variety of.

7. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that described to contain primaquine, parahelium, tertiary ammonia Or the compound of quaternary ammonium salt group is the azo-compound that can pass through heat resolve and/or ultraviolet lighting decomposition generation gas.

8. the manufacture method of water-absorbing resins according to claim 7, it is characterised in that the azo-compound is selected from azo Diisobutyl imidazoline, 2,2'- azos [2- (2- imidazoline -2- bases) propane], 2'2- azos-two (2- methyl) propyl group amidine, 2, 2'- azos [N- (2- ethoxys) -2- methyl-props amidine], diazo aminobenzene, 4- amino -3,2- dimethyl azobenzene, 4- amino are even The hydrochloride or sulfate of pyridine and above-claimed cpd.

9. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the weak acid and/or salt of weak acid are molten Weak acid (salt) in liquid is the organic acid (salt) or inorganic that coordinate bond can be formed with primaquine, parahelium, tertiary ammonia or quaternary ammonium salt group Sour (salt).

10. the manufacture method of water-absorbing resins according to claim 9, it is characterised in that the organic acid (salt) or inorganic Sour (salt) is selected from acetic acid (salt), propionic acid (salt), acrylic acid (salt), lactic acid (salt), glyceric acid (salt), n-butyric acie (salt), isobutyric acid (salt), 3-butenoic acid (salt), methacrylate (salt), positive valeric acid (salt), isovaleric acid (salt), 2- penetenoic acids (salt), 3- penetenoic acids In (salt), 4- penetenoic acids (salt), glutamic acid (salt), n-caproic acid (salt), isocaproic acid (salt), benzoic acid (salt), sulfurous acid (salt) One or more, preferably acetic acid (salt), propionic acid (salt), acrylic acid (salt), 3-butenoic acid (salt), methacrylate (salt), 2- amylenes One or more in sour (salt), 3- penetenoic acids (salt), 4- penetenoic acids (salt), further preferred acetic acid (salt).

11. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the foaming agent solution and weak acid And/or in salt of weak acid solution mixing system preparation infusion particle dispersion step, can be carried out under stirring or static conditions, foam Agent component is 10 with weak acid/salt of weak acid constituent mass ratio:1~1:5000.

12. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the blowing-agent particle can lead to It is 20~200 DEG C to cross chemistry and/or physical reactions release gas, gas release temperature.

13. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that blowing-agent particle dosage is with insatiable hunger With monomer meter, in the range of 0.005~20wt%.

14. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that blowing-agent particle is in unsaturation third Olefin(e) acid system monomer and cross-linking agent aqueous solution prepare before, be dispersed to monomer solution in preparation process or after preparing.

15. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that blowing-agent particle adds in initiator It is added to before entering monomer solution, in adition process or after adding in solution.

16. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that the monomer solution is gathered In the step of conjunction, polymerization start temperature is 20~120 DEG C.

17. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that polymerization process hydrogel can reach The maximum temperature arrived is more than 100 DEG C.

18. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that further comprise aqueous gel Shaped polymer is crushed in the course of the polymerization process or after polymerization.

19. the manufacture method of water-absorbing resins according to claim 18, it is characterised in that further comprise to after crushing Aqueous gel shaped polymer is thermally dried.

20. the manufacture method of water-absorbing resins according to claim 19, it is characterised in that the blowing-agent particle is polymerizeing During, gas is produced in aqueous gel shaped polymer crushing process or during being thermally dried, form loose structure and hand over Linked polymer.

21. the manufacture method of water-absorbing resins according to claim 20, it is characterised in that the loose structure cross-linked polymeric Thing aperture is 10~500 microns.

22. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that further comprise to more after drying Pore structure cross-linked polymer carries out grain refined and sieved.

23. the manufacture method of water-absorbing resins according to claim 1, it is characterised in that further comprise surface crosslinking agent Processing screening after water-absorbing resins near surface, formed covalent bond the step of.

24. the manufacture method of water-absorbing resins according to claim 23, it is characterised in that the surface crosslinking agent be containing The compound of multiple functional groups that covalent bond can be formed with carboxyl reaction on water-absorbing resins.

25. the manufacture method of water-absorbing resins according to claim 24, it is characterised in that surface crosslinking agent is selected from polyalcohol Compound, epoxide, polyamine compounds or with one kind in the condensation product of its halogenated epoxy compound, ethylene carbonate or It is a variety of.

26. the manufacture method of water-absorbing resins according to claim 25, it is characterised in that surface crosslinking agent and water imbibition tree During fat forms covalent bond, it is 100~220 DEG C that it, which is surface-treated temperature,.

27. the manufacture method of water-absorbing resins, further comprises after surface-crosslinked according to claim 26, cation is used Compound processing water-absorbing resins surface, the step of forming ionic bond.

28. the manufacture method of water-absorbing resins according to claim 27, it is characterised in that the cationic compound is sun Ionomer and/or multivalent metal salt.

29. a kind of water-absorbing resins, it is characterised in that absorbed water according to the manufacture method of any one of claim 1 to 28 Property resin, the resin quality median particle diameter be 200~600 microns, loose structure average pore size be 10~500 microns, centrifugation protect Water multiplying power is 25~50g/g, and it is 10~50sec/g that salt velocity is inhaled in swirl method test, and levels of residual monomers is in below 500ppm.