Summary of the invention
The object of the present invention is to provide a kind of super strength water absorbent, its water absorbent rate height, absorption speed is fast.
Another object of the present invention has been to provide a kind of preparation method of super strength water absorbent, and its technology is easy, has solved the copolyreaction medium viscosity and has increased the uneven problem of back stirring.
In order to achieve the above object, the present invention adopts following technical measures:
The rivieri raw material past that proposes among the present invention limits because of the region, and the plantation amount is little, fails to cause enough attention.Now, the significantly raising of konjaku planting technology and output makes it become to have the important agricultural resource that industrialized developing is worth.The major ingredient of konjaku is Rhizoma amorphophalli glucomannan (Konjac Glucomannan, be called for short KGM), it is the natural macromolecule amylose of known plants glue medium viscosity maximum, account for 50~60% of dry product weight, its molecular formula is (C6H10O5) n, and it is in 1: 6 ratio, by β-1 by D-glucose and D-seminose, the composite natral macromolecule polysaccharide of 4 glycosidic link be combined intos, its coefficient of expansion in water is about 100.There is the side chain of β-1,3 key the mannose group C-3 position of this sugar backbone, except that glucose and mannose residue, also has ethanoyl to exist, and its crystalline structure has two kinds on α type (armorphous) and β type (mating type).Have a large amount of hydroxyls in the Rhizoma amorphophalli glucomannan macromolecular structure, can carry out multiple esterification and modified-reaction.Utilize konjaku (konjaku powder, Rhizoma amorphophalli micropowder or full Rhizoma amorphophalli powder), it is carried out the chemically modified macromolecule polysaccharide that molecule obtains having synergistic function after composite modified with physics and chemical process.This polysaccharide owing to have instant, thickening, gelling, plastic, the high absorption of heat, is very good wide spectrum gel, a thickening material of a gellike performance except that the character that possesses natural konjac polysaccharide.Based on the characteristic of rivieri raw material, it is carried out graft copolymerization suction monomer can obtain excellent water absorbing properties.This super strength water absorbent is made by following raw materials according:
1, Rhizoma amorphophalli powder and vinylformic acid mass ratio are 1: 10~1: 100
2, vinylformic acid is that (degree of neutralization is 60mol%~90mol%) with alkali part neutral vinylformic acid in advance
3, initiator and acrylic acid mass ratio are 0.1%~1%
4, linking agent and acrylic acid mass ratio 0.01%~0.8%
The steps include:
With Rhizoma amorphophalli powder after gelatinization under the 30-60 ℃ of temperature (solid content 0.5-5.0%); the passing ratio pump adds refrigerative, and (degree of neutralization is 60mol%~90mol%) with alkali part neutral vinylformic acid; add the initiator of vinylformic acid 0.1Wt%~1Wt% and the linking agent of 0.01Wt%~0.8Wt%; konjaku powder and vinylformic acid mass ratio are 1: 10~1: 100; stir and logical nitrogen or argon shield; after the copolyreaction of 30-70 ℃ of temperature initiation grafting; following reaction solution to spray to enter temperature with nitrogen or argon gas is that 70-130 ℃ helix tube type turbulent flow reactor carries out graft copolymerization; reaction times 30-300Sec; spiral is extruded and is sent into drum-type film forming moisture eliminator; make reactant be membranaceous drying; drying temperature 90-180 ℃, time of drying 0.5-10min.Dry back product is the film sheet, and the film sheet is ground into 60-300 purpose granular product.
In the preparation of konjaku graft co-polypropylene acid (salt) super strength water absorbent, Rhizoma amorphophalli powder can be konjaku powder, Rhizoma amorphophalli micropowder or full Rhizoma amorphophalli powder; Neutralization can be adopted sodium hydroxide or potassium hydroxide with alkali; Initiator is Potassium Persulphate, ammonium persulphate or ceric ammonium nitrate; Linking agent is N, N '-methylene-bisacrylamide, epoxy chloropropane 1,4-butyleneglycol; Logistics stirs and leads to nitrogen or argon gas is protected, the activity of the free radical that produces in the protective reaction in the entire reaction course.It is characterized in that with proportioning pump accurately reinforced.Each raw material all is configured to certain density work mother liquor and is stored in the hold tank, and the passing ratio pump accurately adds in proportion automatically.After the copolyreaction of 30-70 ℃ of temperature initiation grafting, following reaction solution to spray to enter temperature with nitrogen or argon gas is helix tube type turbulent flow reactor-screw transport reactor of 70-130 ℃, carries out graft copolymerization.Carry the heavy-gravity fluid that becomes with air pressure and screw rod power, and force to form turbulent flow, strengthen mixing effect.Reaction product is extruded through screw rod and is sent into drum-type film forming moisture eliminator, makes reactant be membranaceous drying, drying temperature 90-180 ℃, time of drying 0.5-10min.Dry back product is the film sheet, at last the film sheet is ground into 60-300 purpose granular product.
The konjaku super strength water absorbent that relates among the present invention is compared with existing starch based super strength water absorbent, the preparation technology of konjaku graft co-polypropylene acid (salt) super strength water absorbent is simple, solved and stirred problem of non-uniform after viscosity increases in the copolyreaction, and energy whole process protection free radical reaction; Producing apparatus simple structure, compactness; Processing parameter is easy to realize omnidistance online detection, control; The water absorbent rate height of product, absorption speed is fast, gel-strength is big and biodegradable.This product can be widely used in fields such as sanitary material, medical treatment, agricultural gardening.
Embodiment
Example 1:
4.5 parts in the full powder of konjaku is added 100 parts of water (solid content 4.5%) after gelatinization under 40 ℃ of temperature, and the passing ratio pump adds refrigerative with sodium hydroxide part neutral vinylformic acid (degree of neutralization is 80mol%), and full powder of konjaku and vinylformic acid mass ratio are 1: 50.Add the initiator potassium persulfate of vinylformic acid 0.5Wt% and the linking agent N of 0.1Wt%; N '-methylene-bisacrylamide; stir and logical nitrogen protection; after the copolyreaction of 60 ℃ of temperature initiation graftings, following reaction solution to spray to enter temperature with nitrogen is that 90 ℃ helix tube type turbulent flow reactor carries out graft copolymerization, reaction times 240Sec; spiral is extruded and is sent into drum-type film forming moisture eliminator; make reactant be membranaceous drying, 140 ℃ of drying temperatures, time of drying 2min.Dry back product is the film sheet, through being ground into 120 purpose granular products.Product is 1800 times to the specific absorption of pure water, and the specific absorption of physiological saline can reach 170 times, and the specific absorption of 1min pure water and the specific absorption of physiological saline are respectively 1100 times and 100 times.
Example 2:
3.5 parts of konjaku powders are added 100 parts of water (solid content 3.5%) after gelatinization under 35 ℃ of temperature, and the passing ratio pump adds refrigerative with sodium hydroxide part neutral vinylformic acid (degree of neutralization is 70mol%), and konjaku powder and vinylformic acid mass ratio are 1: 80.Add the initiator potassium persulfate of vinylformic acid 0.4Wt% and the linking agent N of 0.2Wt%; N '-methylene-bisacrylamide; stir and logical nitrogen protection; after the copolyreaction of 50 ℃ of temperature initiation graftings, following reaction solution to spray to enter temperature with nitrogen is that 85 ℃ helix tube type turbulent flow reactor carries out graft copolymerization, reaction times 180Sec; spiral is extruded and is sent into drum-type film forming moisture eliminator; make reactant be membranaceous drying, 140 ℃ of drying temperatures, time of drying 2min.Dry back product is the film sheet, through being ground into 100 purpose granular products.The specific absorption of product pure water is 1500 times, and the specific absorption of physiological saline can reach 130 times, and the specific absorption of 1min pure water and the specific absorption of physiological saline are respectively 950 times and 90 times.
Example 3:
4.5 parts in the full powder of konjaku is added 100 parts of water (solid content 4.5%) after gelatinization under 40 ℃ of temperature, and the passing ratio pump adds refrigerative with sodium hydroxide part neutral vinylformic acid (degree of neutralization is 85mol%), and full powder of konjaku and vinylformic acid mass ratio are 1: 50.Add the initiator ammonium persulfate of vinylformic acid 0.8Wt% and the linking agent N of 0.7Wt%; N '-methylene-bisacrylamide; stir and logical argon shield; after the copolyreaction of 60 ℃ of temperature initiation graftings, following reaction solution to spray to enter temperature with argon gas is that 90 ℃ helix tube type turbulent flow reactor carries out graft copolymerization, reaction times 240Sec; spiral is extruded and is sent into drum-type film forming moisture eliminator; make reactant be membranaceous drying, 150 ℃ of drying temperatures, time of drying 2min.Dry back product is the film sheet, through being ground into 120 purpose granular products.The specific absorption of product pure water is 800 times, and the specific absorption of physiological saline can reach 80 times, and the specific absorption of 1min pure water and the specific absorption of physiological saline are respectively 600 times and 65 times.
Example 4:
3.0 parts of Rhizoma amorphophalli micropowders are added 100 parts of water (solid content 3.0%) after gelatinization under 40 ℃ of temperature, and the passing ratio pump adds refrigerative with potassium hydroxide part neutral vinylformic acid (degree of neutralization is 80mol%), and full powder of konjaku and vinylformic acid mass ratio are 1: 80.Add the initiator potassium persulfate of vinylformic acid 0.5Wt% and the linking agent N of 0.4Wt%; N '-methylene-bisacrylamide; stir and logical nitrogen protection; after the copolyreaction of 60 ℃ of temperature initiation graftings, following reaction solution to spray to enter temperature with nitrogen is that 90 ℃ helix tube type turbulent flow reactor carries out graft copolymerization, reaction times 240Sec; spiral is extruded and is sent into drum-type film forming moisture eliminator; make reactant be membranaceous drying, 120 ℃ of drying temperatures, time of drying 3min.Dry back product is the film sheet, through being ground into 200 purpose granular products.The specific absorption of product pure water is 1600 times, and the specific absorption of physiological saline can reach 150 times, and the specific absorption of 1min pure water and the specific absorption of physiological saline are respectively 950 times and 86 times.