CN1317504A - Multi-element graft copolymer of starch and its preparing process and application - Google Patents
Multi-element graft copolymer of starch and its preparing process and application Download PDFInfo
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- CN1317504A CN1317504A CN 01110688 CN01110688A CN1317504A CN 1317504 A CN1317504 A CN 1317504A CN 01110688 CN01110688 CN 01110688 CN 01110688 A CN01110688 A CN 01110688A CN 1317504 A CN1317504 A CN 1317504A
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Abstract
A multi-element graft copolymer of starch is prepared from starch, allyl compound and water as medium through free radical graft copolymerizing reaction at 80-85 deg.C under the action of assistants to obtain salt-resistant high-absorbency resin. Its advantages include easily available raw materials no environmental pollution, and high salt resistance and water absorption.
Description
The present invention relates to starch graft copolymer, its preparation method and purposes.
Super absorbent resin is a kind of strong absorptive functional polymer compound with low crosslinking degree of loose network structure, owing to contain the network structure of strong polarity suction group and Bao Shui in the molecule, it can absorb the hundred times of own wt even several thousand times deionized water, be swelled into hydrogel after the suction immediately, have good suction and water-retentivity.The formed gel in suction back, even confined water also is difficult for extruding, when surrounding environment was dry, water can slowly release again.Behind the resin drying after the suction, water-retaining capacity can recover again.Just, cause people's very big interest, be widely used in fields such as physiological hygiene apparatus, agricultural, agricultural gardening, afforestation, desert, civil construction and fresh-keeping packaging material because super absorbent resin has above-mentioned peculiar function.
The synthetic method of super absorbent resin generally has two kinds of approach: (1) be with natural polymer as: starch, Mierocrystalline cellulose etc. is that raw material and propenyl monomer carry out graft copolymerization.Utilize modes such as light, heat, radiation and initiator, make and produce free radical on the natural polymer subchain, and then the trigger monomer graft polymerization, through the further crosslinked super absorbent resin that makes the natural polymer graft type.(2) use the propenyl monomer fully, under light, heat, radiation and initiator, linking agent effect, behind polymerization crosslinking, obtain complete synthesis type super absorbent resin.Two kinds of approach have his own strong points, and the former cost is low, are convenient to promote the use of in enormous quantities, and latter's water absorbing properties is better.
The water absorbing properties of super absorbent resin is with how much relevant by contained ion in the suction, and the water-retaining capacity of the resin of marking is meant the amount of inhaling deionized water usually, and it is many more to contain inorganic ion in the water, and water regain is few more.In actual applications, water always contains a certain amount of inorganic salt, so solve the salt tolerance of super absorbent resin, its application is of great significance.
Main purpose of the present invention is to solve the high and salt tolerance problem of resin cost, and a kind of salt tolerance, high-hydroscopicity multi-element graft copolymer of starch are provided, and it is convenient at agriculture field, plant trees and desert in promote the use of on a large scale in enormous quantities.The starch grafting type high water absorption resin, raw material is easy to get, and cost is low.Starch is renewable resources, comes from farming and is applied to farming, and is favourable in the people in state.
Another object of the present invention provides the method for the above-mentioned multi-element graft copolymer of starch of preparation.
Also purpose of the present invention provides the purposes by the multi-element graft copolymer of starch of the inventive method preparation.
The method for preparing above-mentioned multi-element graft copolymer of starch comprises: with starch, propenyl compound is main raw material, with water is medium, under the effect of radical initiator and other auxiliary agent, by free radical grafting copolymerization and crosslinking reaction, generate spongy elastomerics, promptly get multi-element graft copolymer of starch one salt-tolerant super absorbent polymer after drying, the pulverizing.
Described main raw material starch is general industry starch, as: W-Gum, yam starch, tapioca (flour), sweet potato starch etc., the preferably high starch of straight chain content.Starch content accounts for 25～35wt% of propenyl compound and starch total amount in the super absorbent resin.
Salt tolerance realizes by multi-grafted technology.The ionized propenyl monomer of every energy, meet water because ionizing event own, water-retaining capacity is stronger, but salt tolerance is relatively poor, and non-ionized propenyl monomer is then opposite, though water-retaining capacity reduces, but salt resistant character is good, and the present invention adopts ionization and unionized propenyl monomer according to this principle, carry out multi-grafted copolyreaction by a certain percentage, make salt-tolerant super absorbent polymer.Unionized propenyl monomer proportion is big more, and salt tolerance is good more, but water-retaining capacity descends.
Described main raw material propenyl compound is the mixture that contains a kind of ionization propenyl compound and at least a unionized propenyl compound at least.Ionization propenyl compound comprises acrylic acid or the like and acrylamide sulfonic compound, and its example for example is vinylformic acid, methacrylic acid, 2-acrylamide-2-methyl propane sulfonic acid etc.Unionized propenyl compound comprises esters of acrylic acid, acrylamides, and its example for example is esters of acrylic acid, acrylamide, methyl acrylic ester, Methacrylamide, crylic acid hydroxy ester class, methacrylic acid hydroxyl ester class, vinyl acetate etc.The ratio of wherein employed ionization propenyl compound and unionized propenyl compound is 65～90: 10～35.The total amount of propenyl compound accounts for 65～75wt% of propenyl compound and starch total amount.
Described radical initiator is water miscible initiator, as: Potassium Persulphate, Sodium Persulfate, ammonium persulphate, ceric ammonium nitrate, hydrogen peroxide, and the oxidation/reduction initiator system of above-claimed cpd and ferrous salt composition.Initiator amount is generally 0.5～2wt% of starch consumption.
Described other auxiliary agent is: 1. reaction control agent, be low-boiling-point organic compound, as: acetone, cyclohexane, sherwood oil etc., its consumption is the reaction solution total amount 0.5～5wt% of (comprising starch, water medium and propenyl compound).2. resin suction rate accelerating material(RAM) is 150～250 purpose natural mineral powders, as: silica powder, kaolin, Paris white, talcum powder etc., its consumption is 1～10wt% of starch consumption.
Raolical polymerizable is thermopositive reaction, can not in time get rid of as the heat that produces, and easily causes sudden and violent gathering, and influences quality product.The present invention adopts the low-boiling-point organic compound reaction control agent, utilizes its volatility, makes the many holes of the inner generation of graft copolymer, is convenient to distributing of heat.In the reaction, add inorganic mineral powder, be mainly the specific surface area that increases resin, the specific surface area of resin is big more, and rate of water absorption is fast more.
The inventive method preferably adopts the disc type polymerization technique.Described disc type polymerization technique is: with the ratio of starch/deionized water=5～10/100, the starch fluid that is configured to, join in the stainless steel or enamel still of band agitating heater, heat while stirring, when treating that temperature rises to 80～95 ℃, add propenyl compound, resin suction rate accelerating material(RAM) more successively, and be neutral with sodium hydroxide solution conditioned reaction liquid.In another stainless steel or enamel material-compound tank, mix with deionized water preparation 0.1～0.5mol/L initiator solution and reaction control agent, and be preheated near the reaction control agent boiling temperature.By a certain percentage reaction solution and initiator solution are joined in the disc type container that applies poly tetrafluoroethylene, grafting and crosslinking reaction can be carried out, and generate spongy solid product rapidly again, and crushed after being dried promptly gets product.
The advantage of disc type polymerization technique: be medium with water 1., cost is low, and product is easily separated, and energy consumption is low; 2. equipment is simple, less investment, and repayment is fast; 3. technology is simple, and is easy to operate; 4. three-waste free pollution.
The multi-element graft copolymer suction deionized water that makes by aforesaid method reaches 300～450g/g, inhales 0.06%CaCl
2Solution reaches 140～160g/g, inhales 0.9%NaCl solution and reaches 120～150g/g.And rate of water absorption is fast, and 6min can reach maximum water-intake rate more than 80%.
Above-mentioned graft copolymer can be widely used in fields such as physiological hygiene apparatus, agricultural, agricultural gardening, afforestation, desert, civil construction and fresh-keeping packaging material.
Below in conjunction with embodiment the present invention is described.
Embodiment 1:
Take by weighing 5kg W-Gum and 100kg deionized water, join have stir and the stainless steel cauldron of heating unit in, be heated to 80～90 ℃, make starch pasting after, add 200 order CaCO successively
360g, vinylformic acid 8kg, methyl acrylate 1kg, acrylamide 1 kg modulates reaction solution with the sodium hydroxide solution of 0.5mol/L and is neutral stand-by.
In another stainless steel material-compound tank, with the ammonium persulfate solution of 50g ammonium persulphate and deionized water preparation 0.1mol/L, and add 1kg acetone, be mixed with the initiator mixing solutions, reheat to 50～55 are ℃ stand-by.
Ratio in reaction solution/initiator mixing solutions=100/2～4 joins in the reaction tray while stirring, and grafting and crosslinking reaction take place immediately, the foam product of generation, and drying is pulverized can get 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 385g/g, inhales 0.06%CaCL
2Solution 150g/g inhales 0.9%NaCL solution 135g/g.
Embodiment 2:
Among the embodiment 1, W-Gum changes yam starch into, CaCO
3Change SiO into
2, then can make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 350g/g, inhales 0.06%CaCL
2Solution 140g/g inhales 0.9%NaCL solution 127g/g.
Embodiment 3:
Among the embodiment 1, vinylformic acid, methyl acrylate, acrylamide change methacrylic acid, methyl methacrylate, Methacrylamide respectively into, and consumption is constant, then can make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 335g/g, inhales 0.06%CaCL
2Solution 138g/g inhales 0.9%NaCL solution 125g/g.Embodiment 4:
Among the embodiment 1, overcurrent acid ammonium changes Potassium Persulphate into, and methyl acrylate changes vinyl acetate into, and acrylamide changes Hydroxyethyl acrylate into, and consumption is constant, then can make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 390g/g, inhales 0.06%CaCL
2Solution 147g/g inhales 0.9%NaCL solution 132g/g.
Embodiment 5:
Among the embodiment 1, vinylformic acid changes the 2-acrylamide-2-methyl propane sulfonic acid of same amount into, then can make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 840g/g, inhales 0.06%CaCL
2Solution 155g/g inhales 0.9%NaCL solution 138g/g.
Embodiment 6:
0.1mol/L ammonium persulfate solution among the embodiment 1 changes 0.2mol/L ceric ammonium nitrate dilute nitric acid solution (containing the 50g ceric ammonium nitrate) into, acetone changes the cyclohexane of same amount into, the initiator solution preheating temperature is 78 ℃, then can make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 380g/g, inhales 0.06%CaCL
2Solution 145g/g inhales 0.9%NaCL solution 130g/g.
Embodiment 7
Identical with embodiment 1, just vinylformic acid is 7kg, and methyl acrylate is 1.5kg, and acrylamide is 1.5kg.Make 15kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 385g/g, inhales 0.06%CaCL
2Solution 150g/g inhales 0.9%NaCL solution 135g/g.
Embodiment 8
Identical with embodiment 1, just W-Gum is 3.8kg, and vinylformic acid is 9kg, and methyl acrylate is 0.5kg, and acrylamide is 0.5 kg.Make 14kg multi-element graft copolymer of starch-salt-tolerant super absorbent polymer.The product water-intake rate is 450g/g, inhales 0.06%CaCL
2Solution 140g/g inhales 0.9%NaCL solution 125g/g.
Claims (9)
1, a kind of multi-element graft copolymer of starch, it is that propenyl compound by the starch of 25～35wt% and 65～75wt% is the multipolymer that medium obtains by free radical polymerisation process with water, gross weight with the two is a base, this multipolymer is inhaled deionized water and is reached 300～450g/g, inhales 0.06%CaCl
2Solution reaches 140～160g/g, inhales 0.9%NaCl solution and reaches 120～150g/g, and rate of water absorption is fast, and 6min can reach maximum water-intake rate more than 80%.
2, the multipolymer of claim 1, described starch are general industry starch, as: W-Gum, yam starch, tapioca (flour), sweet potato starch etc.
3, the multipolymer of claim 1, described propenyl compound is the mixture that contains a kind of ionization propenyl compound and at least a unionized propenyl compound at least, ionization propenyl compound comprises acrylic acid or the like and acrylamide sulfonic compound, its example is a vinylformic acid, methacrylic acid, 2-acrylamide-2-methyl propane sulfonic acid, unionized propenyl compound comprises esters of acrylic acid, acrylamides, its example is an esters of acrylic acid, acrylamide, methyl acrylic ester, Methacrylamide, the crylic acid hydroxy ester class, methacrylic acid hydroxyl ester class, vinyl acetate, the weight ratio of wherein employed ionization propenyl compound and unionized propenyl compound is 65～90: 10～35.
4, the preparation method of the multipolymer of claim 1, it is characterized in that comprising that with starch, propenyl compound be main raw material, with water is medium, under the effect of radical initiator and other auxiliary agent, by free radical grafting copolymerization and crosslinking reaction, generate spongy elastomerics, promptly get multi-element graft copolymer of starch after drying, the pulverizing.
5, according to the method for claim 4, wherein said starch is general industry starch, as: W-Gum, yam starch, tapioca (flour), sweet potato starch etc.
6, method according to claim 4, wherein said propenyl compound is the mixture that contains a kind of ionization propenyl compound and at least a unionized propenyl compound at least, ionization propenyl compound comprises acrylic acid or the like and acrylamide sulfonic compound, its example is a vinylformic acid, methacrylic acid, 2-acrylamide-2-methyl propane sulfonic acid, unionized propenyl compound comprises esters of acrylic acid, acrylamides, its example is an esters of acrylic acid, acrylamide, methyl acrylic ester, Methacrylamide, the crylic acid hydroxy ester class, methacrylic acid hydroxyl ester class, vinyl acetate, the weight ratio of wherein employed ionization propenyl compound and unionized propenyl compound is 65～90: 10～35.
7, according to the method for claim 4, wherein said radical initiator is water miscible initiator, as: Potassium Persulphate, Sodium Persulfate, ammonium persulphate, ceric ammonium nitrate, hydrogen peroxide, and the oxidation/reduction initiator system of above-claimed cpd and ferrous salt composition, initiator amount is 0.5～2wt% of starch consumption.
8, according to the method for claim 4, wherein said other auxiliary agent is: 1. reaction control agent, be low-boiling-point organic compound, as: acetone, hexanaphthene, sherwood oil, its consumption are the reaction solution total amount 0.5～5wt% of (comprising starch, propenyl compound and WATER AS FLOW MEDIUM).2. resin suction rate accelerating material(RAM) is 150～250 purpose natural mineral powders, as: silica powder, kaolin, Paris white, talcum powder, its consumption are 1～10wt% of starch consumption.
9, the purposes of the multi-element graft copolymer of starch of claim 1 in fields such as physiological hygiene apparatus, agricultural, agricultural gardening, afforestation, desert, civil construction and fresh-keeping packaging material.
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| Application Number | Priority Date | Filing Date | Title |
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| CNB011106883A CN1158317C (en) | 2001-04-17 | 2001-04-17 | Multi-element graft copolymer of starch and its preparing process and application |
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| CNB011106883A CN1158317C (en) | 2001-04-17 | 2001-04-17 | Multi-element graft copolymer of starch and its preparing process and application |
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| CN1158317C CN1158317C (en) | 2004-07-21 |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100549100C (en) * | 2005-08-12 | 2009-10-14 | 中国矿业大学(北京) | Humate compound water retaining agent and preparation method thereof |
| CN103041691A (en) * | 2012-09-07 | 2013-04-17 | 赵立地 | Drying agent composition |
| CN103627288A (en) * | 2012-02-27 | 2014-03-12 | 纳路涂料股份有限公司 | Paint composition for vinyl greenhouse and method of manufacturing paint film using the same |
| CN104226488A (en) * | 2014-07-29 | 2014-12-24 | 唐山学院 | Preparation method of micro-fine particle hematite reverse flotation depressing agent |
| CN110003389A (en) * | 2019-03-25 | 2019-07-12 | 北京林业大学 | A kind of environment-friendly type agricultural water-retaining agent and preparation method thereof |
| CN110607177A (en) * | 2019-10-24 | 2019-12-24 | 成都新柯力化工科技有限公司 | Soil water-retaining agent for saline-alkali soil and preparation method thereof |
| CN113307915A (en) * | 2021-04-21 | 2021-08-27 | 安徽工程大学 | Amphiphilic grafted starch slurry and preparation method and application thereof |
| CN115975329A (en) * | 2023-02-14 | 2023-04-18 | 中国科学院兰州化学物理研究所 | Nano silicon oxide modified composite salt-resistant material and preparation method and application thereof |
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2001
- 2001-04-17 CN CNB011106883A patent/CN1158317C/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100549100C (en) * | 2005-08-12 | 2009-10-14 | 中国矿业大学(北京) | Humate compound water retaining agent and preparation method thereof |
| CN103627288A (en) * | 2012-02-27 | 2014-03-12 | 纳路涂料股份有限公司 | Paint composition for vinyl greenhouse and method of manufacturing paint film using the same |
| CN103627288B (en) * | 2012-02-27 | 2016-07-06 | 纳路涂料股份有限公司 | For the method that coating composition and this coating composition of use in greenhouse form film |
| CN103041691A (en) * | 2012-09-07 | 2013-04-17 | 赵立地 | Drying agent composition |
| CN104226488A (en) * | 2014-07-29 | 2014-12-24 | 唐山学院 | Preparation method of micro-fine particle hematite reverse flotation depressing agent |
| CN104226488B (en) * | 2014-07-29 | 2016-08-03 | 唐山学院 | The preparation method of microfine hematite reverse flotation inhibitor |
| CN110003389A (en) * | 2019-03-25 | 2019-07-12 | 北京林业大学 | A kind of environment-friendly type agricultural water-retaining agent and preparation method thereof |
| CN110607177A (en) * | 2019-10-24 | 2019-12-24 | 成都新柯力化工科技有限公司 | Soil water-retaining agent for saline-alkali soil and preparation method thereof |
| CN113307915A (en) * | 2021-04-21 | 2021-08-27 | 安徽工程大学 | Amphiphilic grafted starch slurry and preparation method and application thereof |
| CN115975329A (en) * | 2023-02-14 | 2023-04-18 | 中国科学院兰州化学物理研究所 | Nano silicon oxide modified composite salt-resistant material and preparation method and application thereof |
| CN115975329B (en) * | 2023-02-14 | 2023-09-05 | 中国科学院兰州化学物理研究所 | Nanometer silicon oxide modified composite salt-resistant material and preparation method and application thereof |
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| CN1158317C (en) | 2004-07-21 |
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