CN100349933C - Preparation method of spherical water absorption resin - Google Patents
Preparation method of spherical water absorption resin Download PDFInfo
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- CN100349933C CN100349933C CNB2005100323668A CN200510032366A CN100349933C CN 100349933 C CN100349933 C CN 100349933C CN B2005100323668 A CNB2005100323668 A CN B2005100323668A CN 200510032366 A CN200510032366 A CN 200510032366A CN 100349933 C CN100349933 C CN 100349933C
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- water absorption
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- phase suspension
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Abstract
The present invention discloses a preparation method of spherical water absorption resin. Under the conditions of normal temperature and normal pressure, the spherical water absorption resin is prepared by reverse phase suspension polymerization irradiated by [60]Co-gamma rays. The present invention is characterized in that a water phase comprising acrylic acid, alkaline liquor, a co-monomer and a crosslinking agent and an oil phase comprising span 80, monostearin and a dispersing agent are used for preparing a reverse phase suspension; then, the reverse phase suspension is loaded in a container and stays still corresponding to the container; the reverse phase suspension is put in an irradiation field to receive irradiation, and a reaction kettle is not needed; under the conditions that the dose of the reverse phase suspension is from 0.05 to 2 kGy/h, and the dose of the reverse phase suspension is from 0.5 to 0.2*10<2>kGy, the oil phase is separated after the reaction is finished; after a drying process, spherical water absorption resin is obtained. The appearance of the spherical water absorption resin is spherical, and the spherical water absorption resin has the advantages of uniform grain size, no friability and good water absorption permeability.
Description
Technical field
The invention belongs to the preparation method of water-absorbing resin.
Background technology
Patent documentation CN 02123911.8 " a kind of preparation method of High hydrophilous resin ", CN 200310107773.1 " microwave radiation cellulose base High hydrophilous resin synthetic method ", CN 200410101888.4 " a kind of method of producing high water absorptive resin by wave polymerization " and CN 200410101887.x " a kind of ripple polymerization prepares the method for starch grafting type high water absorption resin " disclose and have adopted microwave radiation to prepare the method for water-absorbing resin, they all adopt microwave radiation to cause, and polymerization process adopts solution polymerization.Patent documentation CN 02114782.5 " a kind of method of preparing high water absorbability resin by irradiation method ", disclose a kind of with vinylformic acid, acrylamide, Propylene glycol monoacrylate, 2-acrylamide-2-methyl propane sulfonic acid, linking agent, under 25～35 ℃ of temperature, be the cobalt of 0.5～5KGy/h with radiation dose rate
60The Co-gamma-ray irradiation obtains the method for water-absorbing resin, and what this method adopted is the ionizing radiation solution polymerization process.More than the roughly production technique of preparation water-absorbing resin is: monomer (one or more) and other reagent are mixed with the aqueous solution, by carrying out initiated polymerization after initiator (one or more) or the ionizing rays, generate block gel, block gel is cut into the fritter after drying, again crushing and classification and water-absorbing resin.Because pulverizing is to carry out under mechanical friction or impact force action, it is irregularly shaped to cause resin to be fragmented into, and product exists particle diameter to differ, and is frangible, not attractive in appearance, deficiencies such as suction poor permeability.
Summary of the invention
Technical problem to be solved by this invention is the defective that overcomes above-mentioned prior art, provides a kind of production technique simple, and outward appearance is spherical in shape, and particle diameter is even, attractive in appearance, and intensity is good, the preparation method of the spherical water absorption resin of suction perviousness excellence.
For solving the problems of the technologies described above, the technical solution adopted in the present invention is: a kind of preparation method of spherical water absorption resin, it is characterized in that using water: vinylformic acid, alkali, comonomer, linking agent and oil phase: span 80, mono-glycerides, dispersion medium are mixed with anti-phase suspension liquid, or use water: vinylformic acid, alkali, linking agent and oil phase: span 80, mono-glycerides, dispersion medium are mixed with anti-phase suspension liquid, under 5～40 ℃ and normal pressure, by
60Co-gamma-rays radiation anti-phase suspension liquid leaves standstill suspension polymerization, must be dispersed in the spherical water absorption resin in the oil phase, isolates oil phase, and is drying to obtain finished product.
As a further improvement on the present invention, the weight percent of described each component of anti-phase suspension liquid is:
Vinylformic acid 35～45%
Alkali 8～25%
Comonomer 0～10%
Linking agent 0.01～0.1%
Span 80 10～20%
Mono-glycerides 0.5～2%
Dispersion medium 20～35%
Its concrete processing step is:
(1) water preparation: in described ratio, alkali is made into the aqueous solution after, vinylformic acid is neutralized to pH value 6～7, add comonomer, linking agent and dissolve, controlled temperature is at 20～60 ℃;
(2) oil phase preparation: span 80, mono-glycerides are placed dispersion medium, be heated to 60～65 ℃ of dissolvings:
(3) in emulsor, add oil phase earlier, start emulsor and stir, in emulsor, add water then, form anti-phase suspension liquid;
(4) with the suspension splendid attire to container, be statically placed in the radiation chamber, the anti-phase suspension liquid temp is controlled at 5～40 ℃, pressure is normal pressure;
(5) be 0.05～2KGy/h in dose rate, dosage is under the condition of 0.5～0.2 * 102kGy, by
60Co-gamma-rays radio polymerization promptly gets the spherical water absorption resin that is dispersed in the oil phase after reaction finishes, and isolates oil phase and dry, promptly gets product.
Described comonomer be have one or two pair key can with the monomer of acrylic acid copolymer.Can be acrylamide, methacrylic acid, butyl acrylate or vinyl acetate between to for plastic.
Described linking agent is reactive monomer, the N of bi-vinyl, N, two (methyl) acrylate of-methylene diacrylamide or polyoxyethylene glycol.
Dispersion medium is organic hydrocarbon, animal oil or vegetables oil in the described oil phase.Described organic hydrocarbon is kerosene, gasoline or naphthenic hydrocarbon.
Described alkali is any one in sodium hydroxide, ammoniacal liquor, the potassium hydroxide.
The present invention compared with prior art adopts
60The Co-gamma-rays, the polymerization of anti-phase suspension initiated polymerization method, the finished product outward appearance is spherical in shape, and particle diameter is even, attractive in appearance, and intensity is good, and is non-friable, suction perviousness excellence.Saved the operation that cuts into fritter, technology is simple, excellent product performance.When initiated polymerization, the container of splendid attire suspension need not installed whipping device, suspension is in accepting the irradiation process, can adopt dynamic or static irradiation, but suspension is actionless with respect to the container of splendid attire, and whole suspension polymerization process adopts and leaves standstill polymerization, does not need reactor, make production unit simple, cost is low.Carry out under the polymerization normal temperature and pressure, safe and reliable.
Embodiment
The preparation method of spherical water absorption resin of the present invention, be to be mixed with anti-phase suspension liquid with vinylformic acid, alkali, comonomer, linking agent, span 80, mono-glycerides, dispersion medium, or be mixed with anti-phase suspension liquid with vinylformic acid, alkali, linking agent, span 80, mono-glycerides, dispersion medium, under 5～40 ℃ and normal pressure, by
60Co-gamma-rays radiation anti-phase suspension liquid leaves standstill suspension polymerization, isolates oil phase and dry, gets product.
Embodiment 1
Take by weighing 15 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, (wherein alkali is NH slowly to add 27% ammoniacal liquor
3Content is 3.25 kilograms), make neutral temperature be controlled at 20 ℃, this moment, PH=6～7 added 2.5 kilograms of acrylamides then, linking agent N, N, 0.005 kilogram of-methylene diacrylamide is water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding 13.5 kilograms in dispersion medium kerosene, span 80,6 kilograms, 0.3 kilogram of mono-glycerides mixes and is heated to 60～65 ℃ of dissolvings, then water is added to oil phase, stirs and promptly gets anti-phase suspension liquid after 1～2 hour.After anti-phase suspension liquid splendid attire was in the container, the anti-phase suspension liquid temp was controlled at 5 ℃, places
60In the Co-gamma field, dose rate is 0.05KGy/h, and dosage is 2KGy,, need not to stir, be statically placed in the irradiation field, to accept radiation and leave standstill polymerization, reaction finishes and obtains spherical water absorption resin, isolates oil phase, promptly gets product in infrared dryer after the drying.
Embodiment 2
Take by weighing 25 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, potassium hydroxide is configured to 30% the aqueous solution for 15.5 kilograms, slowly adds in the vinylformic acid, make neutral temperature be controlled at 20 ℃, this moment PH=6～7, add 2.5 kilograms of methacrylic acids then, 0.05 kilogram of two (methyl) acrylate of polyoxyethylene glycol are water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding 15.5 kilograms in gasoline, span 80,9.5 kilograms, 0.6 kilogram of mono-glycerides mixes and is heated to 60～65 ℃ of dissolvings, then water is added to oil phase, stirs and promptly gets anti-phase suspension liquid after 1～2 hour.After anti-phase suspension liquid splendid attire is in the container, place
60In the Co-gamma field, dose rate is 0.05KGy/h, and dosage is 3KGy, the anti-phase suspension liquid temp is controlled at 30 ℃, accepts radiation and leaves standstill polymerization, and reaction finishes and obtains being dispersed in spherical water absorption resin in the oil phase, isolate oil phase, in infrared dryer, promptly get product after the drying.
Embodiment 3
Take by weighing 26.25 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, and sodium hydroxide is configured to 20.7% the aqueous solution for 10.5 kilograms, slowly add in the vinylformic acid, make neutral temperature be controlled at 50 ℃, this moment, PH=6～7 added 1.5 kilograms of butyl acrylates then, N, N, 0.025 kilogram of-methylene diacrylamide is water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding 20.5 kilograms in kerosene, span 80,9.5 kilograms, 0.25 kilogram of mono-glycerides mixes and is heated to 60～65 ℃ of dissolvings, then water is added oil phase, stirs and promptly gets anti-phase suspension liquid after 1～2 hour.After anti-phase suspension liquid splendid attire is in the container, place
60In the Co-gamma field, dose rate is for being 1KGy/h, and dosage is 3kGy, the anti-phase suspension liquid temp is controlled at 10 ℃, accepts radiation and leaves standstill polymerization, and reaction finishes and obtains being dispersed in spherical water absorption resin in the oil phase, isolate oil phase, in infrared dryer, promptly get product after the drying.
Embodiment 4
Take by weighing 15 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, and sodium hydroxide is configured to 20.7% the aqueous solution for 6.0 kilograms, slowly add in the vinylformic acid, make neutral temperature be controlled at 60 ℃, this moment, PH=6～7 added 2 kilograms of vinyl acetate between to for plastics then, N, N, 0.025 kilogram of-methylene diacrylamide is water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding 7.8 kilograms in kerosene, span 80,7 kilograms, 0.75 kilogram of mono-glycerides mixes and is heated to 60～65 ℃ of dissolvings, then water is added oil phase, stirs and promptly gets anti-phase suspension liquid after 1～2 hour.After in the anti-phase suspension liquid container containing, place
60In the Co-gamma field, dose rate is for being 1KGy/h, and dosage is 20kGy, the anti-phase suspension liquid temp is controlled at 40 ℃, accepts radiation and leaves standstill polymerization, and reaction finishes and obtains being dispersed in spherical water absorption resin in the oil phase, isolate oil phase, in infrared dryer, promptly get product after the drying.
Embodiment 5
Take by weighing 18.5 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, and sodium hydroxide is configured to 20.7% the aqueous solution for 7.2 kilograms, slowly add in the vinylformic acid, make neutral temperature be controlled at 25 ℃, this moment, PH=6～7 added 3.5 kilograms of vinyl acetate between to for plastics then, N, N, 0.05 kilogram of-methylene diacrylamide is water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding hexanaphthene, 13 kilograms, span 80,10 kilograms, 0.6 kilogram of mono-glycerides,, mix and be heated to 60～65 ℃ of dissolvings, then water is added oil phase, stir and promptly get anti-phase suspension liquid after 1～2 hour.After anti-phase suspension liquid splendid attire is in the container, place
60In the Co-gamma field, dose rate is 2KGy/h, and dosage is 10kGy, the anti-phase suspension liquid temp is controlled at 15 ℃, accepts radiation and leaves standstill polymerization, and reaction finishes and obtains being dispersed in spherical water absorption resin in the oil phase, isolate oil phase, in infrared dryer, promptly get product after the drying.
The spherical water absorption resin profile of the inventive method preparation is spherical, have attractive in appearance, particle diameter evenly, the characteristics of suction good penetrability, its performance sees the following form:
Embodiment 6
Take by weighing 12 kilograms in vinylformic acid, add in the stainless steel have chuck and agitator and in the still, chuck fills recirculated water, and sodium hydroxide is configured to 20.7% the aqueous solution for 5.0 kilograms, slowly adds in the vinylformic acid, make neutral temperature be controlled at 35 ℃, this moment PH=6～7, N, N, 0.025 kilogram of-methylene diacrylamide is water after the stirring and dissolving.
Start the emulsification pretreatment agitator, toward wherein adding 10 kilograms in kerosene, span 80,4 kilograms, 0.5 kilogram of mono-glycerides mixes and is heated to 60～65 ℃ of dissolvings, then water is added oil phase, stirs and promptly gets anti-phase suspension liquid after 1～2 hour.After in the anti-phase suspension liquid container containing, place
60In the Co-gamma field, dose rate is for being 1KGy/h, and dosage is 20kGy, the anti-phase suspension liquid temp is controlled at 20 ℃, accepts radiation and leaves standstill polymerization, and reaction finishes and obtains being dispersed in spherical water absorption resin in the oil phase, isolate oil phase, in infrared dryer, promptly get product after the drying.
Suction multiple: refer to the liquid absorption when water-absorbing resin absorption liquid reaches capacity, measuring method: N=(W
1-W
0)/W
0* 100%, the g/g of unit.Wherein: N is suction multiple, W
1Weight after the finger imbibition, W
0Refer to the preceding weight resin of imbibition.
Rate of liquid aspiration then reaches capacity with the water-absorbing resin imbibition or approaching saturated (90%) required time representation, the min of unit (minute)
Order footpath: adopt the standard sieve meter.
The container of splendid attire anti-phase suspension liquid need not installed whipping device, and anti-phase suspension liquid can adopt dynamic or static irradiation in accepting the irradiation process, but the anti-phase suspension liquid phase is actionless for the container of splendid attire, does not need to adopt reactor.
Claims (7)
1, a kind of preparation method of spherical water absorption resin is characterized in that using water: vinylformic acid, alkali, comonomer, linking agent and oil phase: span 80, mono-glycerides, dispersion medium are mixed with anti-phase suspension liquid, under 5～40 ℃ and normal pressure, by
60Co-gamma-rays radiation anti-phase suspension liquid leaves standstill suspension polymerization, must be dispersed in the spherical water absorption resin in the oil phase, isolates oil phase, and is drying to obtain finished product, and the weight percent of described each component of anti-phase suspension liquid is:
Vinylformic acid 35～45%
Alkali 8～25%
Comonomer 0～10%
Linking agent 0.01～0.1%
Span 80 10～20%
Mono-glycerides 0.5～2%
Dispersion medium 20～35%,
Wherein said dispersion medium is organic hydrocarbon, animal oil or vegetables oil.
2, the preparation method of spherical water absorption resin according to claim 1 is characterized in that its concrete processing step is:
(1) water preparation: in described ratio, alkali is made into the aqueous solution after, vinylformic acid is neutralized to pH value 6～7, add comonomer, linking agent and dissolve, controlled temperature is at 20～60 ℃;
(2) oil phase preparation: span 80, mono-glycerides are placed dispersion medium, be heated to 60～65 ℃ of dissolvings;
(3) in emulsor, add oil phase earlier, start emulsor and stir, in emulsor, add water then, form anti-phase suspension liquid;
(4) with anti-phase suspension liquid splendid attire to container, be statically placed in the radiation chamber, the anti-phase suspension liquid temp is controlled at 5～40 ℃, pressure is normal pressure;
(5) be 0.05～2KGy/h in dose rate, dosage is 0.5～0.2 * 10
2Under the condition of kGy, by
60Co-gamma-rays radio polymerization promptly gets the spherical water absorption resin that is dispersed in the oil phase after reaction finishes, and isolates oil phase and dry, promptly gets product.
3, the preparation method of spherical water absorption resin according to claim 1 and 2, it is characterized in that described comonomer be have one or two pair key can with the monomer of acrylic acid copolymer.
4, the preparation method of spherical water absorption resin according to claim 3 is characterized in that described comonomer is acrylamide, methacrylic acid, butyl acrylate or vinyl acetate between to for plastic.
5, the preparation method of spherical water absorption resin according to claim 1 and 2 is characterized in that described linking agent is reactive monomer, the N of bi-vinyl, N, two (methyl) acrylate of-methylene diacrylamide or polyoxyethylene glycol.
6, the preparation method of spherical water absorption resin according to claim 1 and 2 is characterized in that described organic hydrocarbon is kerosene, gasoline or naphthenic hydrocarbon.
7, the preparation method of spherical water absorption resin according to claim 1 and 2 is characterized in that described alkali is any one in sodium hydroxide, ammoniacal liquor, the potassium hydroxide.
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| CN100349933C true CN100349933C (en) | 2007-11-21 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101550214B (en) * | 2008-04-02 | 2011-04-27 | 西北工业大学 | Preparation method for polyacrylic acid large-grain bead-shaped water absorbing resin |
| CN103130942B (en) * | 2011-11-22 | 2017-10-03 | 范立涛 | The preparation method and its cold/hot dressing product of a kind of spherical water-absorbent resin |
| CN103937139B (en) * | 2014-04-30 | 2016-06-08 | 西北大学 | The preparation method of poly-(acrylic acid-vinylacetate)-polyethylene alcohol interpenetrating network super absorbent resin |
| CN105061672B (en) * | 2015-08-10 | 2017-10-03 | 湖南省核农学与航天育种研究所 | A kind of preparation method of reversed-phase emulsion PAMA |
| CN108003856B (en) * | 2017-12-01 | 2020-07-07 | 北京恒聚化工集团有限责任公司 | Beaded microsphere profile control water shutoff agent and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85102156A (en) * | 1985-04-05 | 1987-01-14 | 黑龙江省科学院技术物理研究所 | Radiation prepares the method for super composite absorbent material |
| WO2002010229A1 (en) * | 2000-08-02 | 2002-02-07 | Degussa Bauchemie Gmbh | Water-soluble or water-swellable, associatively thickening copolymers containing sulfo groups, method for producing the same and use thereof |
| CN1386771A (en) * | 2002-05-31 | 2002-12-25 | 安徽省农业科学院原子能农业应用研究所 | Resin with superhigh hydroscopicity and its synthesizing process |
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2005
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85102156A (en) * | 1985-04-05 | 1987-01-14 | 黑龙江省科学院技术物理研究所 | Radiation prepares the method for super composite absorbent material |
| WO2002010229A1 (en) * | 2000-08-02 | 2002-02-07 | Degussa Bauchemie Gmbh | Water-soluble or water-swellable, associatively thickening copolymers containing sulfo groups, method for producing the same and use thereof |
| CN1386771A (en) * | 2002-05-31 | 2002-12-25 | 安徽省农业科学院原子能农业应用研究所 | Resin with superhigh hydroscopicity and its synthesizing process |
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