CN102432892A - Method for dissolving cellulose and method for preparing regenerated fiber - Google Patents
Method for dissolving cellulose and method for preparing regenerated fiber Download PDFInfo
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- CN102432892A CN102432892A CN2011102231030A CN201110223103A CN102432892A CN 102432892 A CN102432892 A CN 102432892A CN 2011102231030 A CN2011102231030 A CN 2011102231030A CN 201110223103 A CN201110223103 A CN 201110223103A CN 102432892 A CN102432892 A CN 102432892A
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Abstract
The invention relates to a method for dissolving cellulose, comprising the following steps of: under the condition with the temperature being 0-25 DEG C, firstly mixing the cellulose and a solvent with the weight accounting for 30-70wt% of the total weight of the solvent for dissolving the cellulose uniformly by kneading and shearing; then adding the remaining solvent for dissolving the cellulose at the temperature of 15 below zero to 5 DEG C; and putting the mixture at the temperature of 8 below zero to 25 DEG C, kneading, shearing, mixing uniformly and obtaining cellulose solution. The solvent is water solution containing alkali, urea/thiourea and polyethylene glycol. The method can prevent colloidal particles, micelles and white cores from forming when the cellulose is dissolved, thus leading the cellulose to be well dissolved and obtaining uniform solution; and after the cellulose solution is defoamed, spinning solution is treated by secondary coagulating bath with the coagulating liquid being salt solution to obtain the cellulose fiber, the recovery and utilization cost of the solvent and a coagulating agent is reduced greatly, the rapid coagulation is avoided, the drawing and orientation degree is improved and the regenerated cellulose fiber with better strength is prepared.
Description
Technical field
The present invention relates to a kind of method of dissolving cellulos, and the method for preparing regenerated cellulose fibre.
Background technology
Mierocrystalline cellulose is the abundant natural biological macromolecular materials of nature reserves; But have characteristics such as recyclability, biological degradability, biocompatibility derivatize; Be widely used in fields such as weaving, papermaking, medical treatment, health, environmental engineering; Especially regenerated cellulose fibre with its special gloss, good water absorbability and textile processibility, is important textile fibres always.Yet, owing to have very strong intramolecularly and intermolecular ydrogen bonding in the Mierocrystalline cellulose, make it can not fusion, also be difficult to dissolving, thereby also be far from being fully utilized.
At present, the technical bottleneck that is widely applied of restriction Mierocrystalline cellulose is simple, free of contamination dissolving of its low cost, process and processing.Over more than 100 year, the serious traditional viscose process of environmental pollution is the main method that regenerated cellulose fibre is produced always.Traditional cuprammonium process is produced copper ammonia fibre and is also had environmental pollution, costs an arm and a leg and the shortcoming of difficult solvent recovery.In the last thirty years, though found that many solvents can be directly or through derivatize dissolving cellulos, preparation regenerated cellulose fibre, have mostly in the prior art that environmental pollution, process are numerous and diverse, the high such or such problem of cost and be difficult to industrialization.At present, more noticeable Mierocrystalline cellulose novel solvent mainly contains the composite aqueous solvent system of N-methyl-N-morpholine oxide, ionic liquid and alkali and urea or other material.
The Lyocell fiber of N-methyl-N-morpholine oxide solvent method, Austrian Lenzing company has formed about 150,000 tons/year throughput, but because solvent is expensive; The solvent recuperation difficulty is big; Problems such as dissolution conditions is harsh, and the potential safety hazard of solvent blast is big, suitability for industrialized production is made slow progress.
The ion liquid solvent legal system is equipped with regenerated cellulose fibre and still is in development, do not form industrialization even pilot scale production as yet, and still there are problems such as solvent costliness in this method.
Aqueous sodium hydroxide solution is most economical cellosolve, but this solvent only can dissolve the lower Mierocrystalline cellulose of molecular weight, and the regenerated cellulose fibre intensity that makes is very low, and its cellulose solution is very unstable, is easy to gelation, is not suitable for industrial applications.Discovering in recent years, alkali (sodium hydroxide or Lithium Hydroxide MonoHydrate)/urea or (with) thiocarbamide/water compounded solvents system can dissolve the bigger Mierocrystalline cellulose of molecular weight, and give stability of solution.Adopt alkali/urea or (with) method of thiocarbamide/water compounded solvents system dissolving cellulos; Can pass through the freeze-thaw dissolving cellulos; Or it is plain with sodium hydroxide or lithium hydroxide aqueous solution pretreatment of fiber earlier; And then add urea or thiourea solution dissolving, perhaps directly Mierocrystalline cellulose is dissolved in the mixed aqueous solution of refrigerative sodium hydroxide or Lithium Hydroxide MonoHydrate and urea or thiocarbamide.And further exploration ground is arranged or prepare the method for regenerated cellulose fibre with pilot scale through wet-spinning.The method of sodium hydroxide/sodium zincate/urea mixed aqueous solution solvent system and dissolving cellulos thereof is disclosed among the CN 101130605A.Donghua University application is open or reported in refrigerative alkali (sodium hydroxide or Lithium Hydroxide MonoHydrate)/thiocarbamide/urea mixed aqueous solution dissolving cellulos and prepared the method for regenerated cellulose fibre through wet-spinning.
Above-mentioned sodium hydroxide/sodium zincate/urea mixed aqueous solution solvent system because of zine ion is poisonous, all has the intensive toxic to freshwater plant, planktonic organism, is inappropriate for industrial application; Adopt above-mentioned freeze-thaw technical scheme, facts have proved, must mixed slurry (20 ℃) maintenance under freezing conditions of Mierocrystalline cellulose and solvent be frozen into ice in 3～8 hours, thaw then and could make cellulose solution by dissolving cellulos, also be difficult for industriallization; And it is plain for earlier with sodium hydroxide or lithium hydroxide aqueous solution pretreatment of fiber; Add the dissolving of urea or thiourea solution then; Or directly with Mierocrystalline cellulose refrigerative alkali (sodium hydroxide or Lithium Hydroxide MonoHydrate)/urea or (with) dissolving and prepare the method for regenerated cellulose fibre in the thiocarbamide mixed aqueous solution; Exist following not enough: the time that the solubilized stable liquid state is kept is short; Form easily irreversible gel, and the higher stability of solution of temperature drift or on the low sidely all can cause gelation, especially cellulose concentration or molecular weight is poorer; Solvent system still lacks strong dissolving power, and the cellulose concentration that can reach homogeneous solution is lower; Cellulose dissolution is bad, solution is uneven, and perhaps the concentration because of alkaline solution alkali is bigger, when generating soda cellulose, is easy to cause Mierocrystalline cellulose to degrade fast, thereby the quality of using the made cellulose prods of this kind cellulose solution will obviously be reduced.
When the preparation regenerated cellulose fibre,, all do precipitation bath with the mixed aqueous solution of aqueous acid or salt brine solution or acid and its salt no matter be one precipitation bath method of employing or twice precipitation bath method.These acid and acid-salt, especially acid has tool corrodibility to equipment and human body skin, sucks the also harmful HUMAN HEALTH of steam of these solution for a long time, and the discharge of wastewater that contains these acid and salt pollutes the environment; When the spray silk gets into precipitation bath; The intensive neutralization reaction takes place rapidly and generates salt and heat release (heat release is unfavorable for the temperature control of precipitation bath) in the solvent composition alkali in these acid and the cellulose solution; Equally; Also can generate salt with the urea or the thiocarbamide reaction of solvent composition neutral and alkali, hydrolysis also possibly take place and emit irritating poisonous ammonia, hydrogen sulfide in urea or thiocarbamide in these precipitation bath; On the other hand; Sodium hydroxide or Lithium Hydroxide MonoHydrate meeting and acid-salt and other salt react and generate new salt; Also can emit ammonia with the ammonium salt reaction; The existence of these multiple reactions, not only consuming solvent and peptizer and make it can not recycle and reuse, and makes the precipitation bath complicated componentization and increase the difficulty and the expense of liquid waste disposal.Therefore, these methods both had been unfavorable for environmental protection, and the cost of production process is increased.
Polyoxyethylene glycol is the environmental friendliness material, is to be considered to one of nontoxic, safest macromolecular compound at present, and the compound aqueous solution of its aqueous solution, particularly itself and alkali, salt is considered to novel green solvent.In publication number CN101397369A, disclose a kind of sodium hydroxide/polyoxyethylene glycol aqueous solution solvent system and through freeze-thaw or in the solvent system of precooling the direct method of dissolving cellulos; But facts have proved; This solvent system solubilized Microcrystalline Cellulose and regenerated cellulose, but natural celluloses such as the dissolving cotton pulp dregs of rice, wood pulps is limited in one's ability.
Summary of the invention
The method that the purpose of this invention is to provide a kind of dissolving cellulos, the formation of micelle, micelle and Bai Xin when the method for this dissolving cellulos can be avoided cellulose dissolution, thus make the Mierocrystalline cellulose excellent dissolution, obtain uniform solution; Also avoided cellulose degradation.
Another object of the present invention provides a kind of preparation method of regenerated cellulose fibre; Chemical reaction does not take place in this preparation method solvent, peptizer in process of setting; Significantly reduce solvent, peptizer recycling cost, simultaneously, avoid rapid solidification; Improve the stretch orientation degree, made the better regenerated cellulose fibre of intensity.
A kind of method of dissolving cellulos comprises the steps:
Be under 0～25 ℃ the condition in temperature; Earlier that Mierocrystalline cellulose is even through mediating shear-mixed with the solvent of the solvent gross weight 30～70wt% that accounts for dissolving cellulos; And then add remaining, temperature solvent for-15～5 ℃ dissolving cellulos; And, be placed on that to mediate shear-mixed under-8～25 ℃ the temperature even, promptly obtain the homogeneous fibre cellulose solution.
It is the uniform mixing that has the equipment realization material of good kneading, shear effect through single screw rod or twin screw extruder, kneader, mixing roll, colloidal mill or intensive mixer that described kneading is sheared.
The solvent of described dissolving cellulos comprises following component:
The aqueous solution of polyoxyethylene glycol of urea and 0.4～6.0wt% that contains sodium hydroxide, the 8.5～22.0wt% of 6.0～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.4～6.0wt% that contains sodium hydroxide, the 3.5～6.5wt% of 8.5～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～5.5wt% that contains Lithium Hydroxide MonoHydrate, the 4.5～25.0wt% of 3.5～7.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.3～5.5wt% that contains Lithium Hydroxide MonoHydrate, the 2.5～6.5wt% of 3.5～7.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.2～5.0wt% that contains thiocarbamide, the 2.0～15.5wt% of sodium hydroxide, the 3.0～8.5wt% of 5.0～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.2～5.0wt% that contains thiocarbamide, the 0.5～15.0wt% of Lithium Hydroxide MonoHydrate, the 2.0～6.5wt% of 3.0～7.5wt%.
Preferably, the solvent of described dissolving cellulos comprises following component:
The aqueous solution of polyoxyethylene glycol of urea and 0.5～4.5wt% that contains sodium hydroxide, the 10.0～18.0wt% of 7.0～10.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.5～4.5wt% that contains sodium hydroxide, the 4.0～5.5wt% of 9.0～10.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.4～4.0wt% that contains Lithium Hydroxide MonoHydrate, the 6.0～20.0wt% of 4.0～6.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.4～4.0wt% that contains Lithium Hydroxide MonoHydrate, the 3.0～5.5wt% of 4.0～6.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～3.5wt% that contains thiocarbamide, the 3.0～10.5wt% of sodium hydroxide, the 4.0～6.5wt% of 7.0～10.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～3.5wt% that contains thiocarbamide, the 2.0～10.0wt% of Lithium Hydroxide MonoHydrate, the 3.0～5.5wt% of 3.5～6.0wt%.
Preferably, the number-average molecular weight of described polyoxyethylene glycol is 150～1000000, and more preferably the molecular weight of polyoxyethylene glycol is 800～500000.
Preferably; Be under 5～20 ℃ the condition in temperature; Earlier that Mierocrystalline cellulose is even through mediating shear-mixed with the solvent of the solvent gross weight 40～65wt% that accounts for dissolving cellulos, and then add remaining, temperature solvent for-12～0 ℃ dissolving cellulos, and; Be placed on that to mediate shear-mixed under-8～20 ℃ the temperature even, promptly obtain the homogeneous fibre cellulose solution.
Preferably, described Mierocrystalline cellulose comprises bamboo pulp, wood pulps or the cotton pulp dregs of rice, perhaps viscose fiber, lyocell fiber and non-woven fabrics thereof.
Cellulose solution of the present invention forms through solvent is mixed with Mierocrystalline cellulose at twice; For the first time under temperature is 0～25 ℃ condition; Partial solvent is mixed with Mierocrystalline cellulose, make Mierocrystalline cellulose be able to infiltration, swelling, thereby be easy to dissolving when solubilizing agent dissolves in the second time; Owing to Mierocrystalline cellulose under this temperature does not dissolve, swelling is slow; Can guarantee Mierocrystalline cellulose inside to be able to swelling and can avoid dissolving the white core phenomenon of time surface swelling, the fast and inner indissoluble of dissolving, simultaneously, this preparatory uniform mixing can make when the second time solubilizing agent dissolving Mierocrystalline cellulose fast, be dispersed in the solvent.Like this, add solvent remaining, that temperature is in the cellulose dissolution temperature for the second time then and carry out mixed dissolution, can obtain high-quality cellulose solution.Because twice adding is same solvent system, whole material is easy to mix, and the cellulose degradation when avoiding earlier with high alkali liquid pretreatment of fiber element.
And prior art; Directly Mierocrystalline cellulose is joined when dissolving in the solvent that is in its solvent temperature; Because of the part Mierocrystalline cellulose fast dissolving soltion viscosity is increased contains be not uniformly dispersed as yet or the Mierocrystalline cellulose obstruction solvent of indissoluble to its diffusion, infiltration; Thereby make it be difficult to dissolving and easy micelle, the micelle of forming, or because of cellulose surface swelling, the white core of the too fast and easy formation of dissolving, these all cause, and cellulose dissolution is bad, solution is uneven; For generating soda cellulose with alkaline solution pretreatment of fiber element earlier; And then add urea or thiocarbamide carries out the dissolved method; Because of the concentration of alkaline solution alkali bigger; When generating soda cellulose, be easy to cause Mierocrystalline cellulose to degrade fast, thereby the quality of using the made cellulose prods of this kind cellulose solution will obviously be reduced.
The present invention selects for use the aqueous solution of urea/sulphur urea, polyoxyethylene glycol and sodium hydroxide/Lithium Hydroxide MonoHydrate as dissolution solvent; Because the synergy between the solvent; Make cellulose solution stability improve; Also make simultaneously cellulose concentration improve,, can make the uniform and stable solution of cellulose concentration up to 15wt% as for the polymerization degree being 250 natural cellulose.
A kind of preparation method of regenerated cellulose fibre comprises the steps:
(1) cellulose solution gets spinning solution after deaeration; Stoste through the spinning jet ejection is solidified in first precipitation bath; Described first precipitation bath is a kind of in 5～30wt% aqueous sodium persulfate solution, 5～25wt% sodium acetate aqueous solution, 10～30wt% sodium chloride aqueous solution or the 5～25wt% sodium phosphate aqueous solution, and temperature is 5～30 ℃;
(2) solidify and in second precipitation bath, solidify through step (1) through the fiber after the drawing-off; Through further obtaining cellulosic fibre through follow-up processing again after the drawing-off; Wherein, Described second precipitation bath be mass percent concentration be 2～15wt% aqueous sodium persulfate solution, sodium acetate aqueous solution, sodium chloride aqueous solution or sodium phosphate aqueous solution in a kind of, perhaps be pure water, coagulation bath temperature is 45～95 ℃.
Described follow-up processing comprise with solidify, fiber after the drawing-off successively through wash, oil, drying, winding process, obtain regenerated cellulose fibre.
Preferably, cellulosic content is 2～15wt% in the cellulose solution.
Preferably, the temperature of spinning of cellulose stoste is 0～30 ℃.
Preferably, the cellulosic polymerization degree of described cellulose solution is 250-1500; More preferably polymkeric substance is the cotton pulp dregs of rice or the wood pulps of 300-800.
Preferably, first precipitation bath is 5～30wt% aqueous sodium persulfate solution; More preferably first precipitation bath is 10～25wt% aqueous sodium persulfate solution.
Preferably, second precipitation bath is 3～10wt% aqueous sodium persulfate solution or pure water; Most preferably second precipitation bath is a pure water.
Preferably, the temperature of second precipitation bath is 55～90 ℃; Most preferably the temperature of second precipitation bath is 65～85 ℃.
Preferably, described cellulose solution is prepared from the method for above-mentioned dissolving fiber.
Because adopting nontoxic neutrality or weakly alkaline salt and pure water is peptizer; These peptizer can not decompose under the spinning curing condition; Can not cause the cellosolve component to be decomposed yet, more not can with cellosolve component generation chemical reaction, thereby not only manufacturing processed environmental protection; Also avoided solvent, the chemical depletion of peptizer and the precipitation bath complicated componentization that is caused, thereby the recycling cost of solvent, peptizer is greatly reduced.Precipitation bath separates solvent after filtering purification with peptizer, solvent and peptizer all can be recycled; On the other hand; In precipitation bath of the present invention; The process of setting of Mierocrystalline cellulose strand is merely solvent and non-solvent mutual diffusion behavior and is not to relate to chemical N-process; Process of setting quite relaxes in the first road precipitation bath, and the Mierocrystalline cellulose strand is evenly solidified, and can not implement high stretch orientation between cellulosic molecule before the hydrogen bond network being completed into as yet of this process; Then through in the second road precipitation bath, fully solidifying regeneration and further stretch orientation, thereby obtain the good mechanical performance (regenerated cellulose fibre of intensity >=2.3cN/dtex).
Compared with prior art, the invention has the advantages that:
First; The method of dissolving cellulos of the present invention; Solvent system utilizes polyoxyethylene glycol to be prone to form with Mierocrystalline cellulose and water the characteristic and the molecule chain flexibility thereof of hydrogen bond; With itself and urea or (with) the thiocarbamide Application of composite common with alkali (sodium hydroxide or Lithium Hydroxide MonoHydrate) generation synergistic effect, thereby strengthened the ability of solvent system dissolving cellulos, especially improved the stability of cellulose solution; Elder generation is with partial solvent dipping, the swollen cellulose of same system; And then add cold solvent and be controlled at solvent temperature and dissolve; Bad and the first cellulose degradation during with the high alkali liquid activation of cellulose dissolution when having avoided directly under solvent temperature dissolving, thus high-quality homogeneous solution obtained.
Second; The present invention prepares the method for regenerated cellulose fibre; Because adopting nontoxic neutrality or weakly alkaline salt and pure water is peptizer; Having avoided with corrosive, the acid that is harmful to health or acid-salt is peptizer because of the consumption of solvent that chemical reaction was caused and peptizer and because of the solvent composition hydrolysis give off poisonous gas, and cost reduces, the process environmental protection thereby make; Simultaneously, avoided because of the rapid solidification due to the neutralization of solvent and peptizer chemistry.Relax, solidify regenerative process fully through implementing sectional, make fiber in forming process, be able to super drawing and be orientated and obtain to solidify uniformly revived structure, thereby improve the physical and mechanical properties of fiber.Thereby the present invention obviously improved Technological Economy property, has better industrial prospect.
Embodiment
Embodiment 1
3.6g exsiccant wood pulps (polymerization degree 400) and 40g 7.5wt% sodium hydroxide/11.0wt% urea/1.5wt% polyoxyethylene glycol (molecular weight 800) mixed aqueous solution kneading shear-mixed under 8 ℃ is even; Then to wherein adding 7.5wt% sodium hydroxide/11.0wt% urea/1.5wt% polyoxyethylene glycol (molecular weight 800) mixed aqueous solution of 60g temperature for-15 ℃; And the kneading shear-mixed is even down to place 25 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 2
3.8g exsiccant bamboo pulp (polymerization degree 400) and 30g 9.2wt% sodium hydroxide/4.5wt% thiocarbamide/0.4wt% polyoxyethylene glycol (molecular weight 4000) mixed aqueous solution kneading shear-mixed under 25 ℃ is even; Then to wherein adding 9.2wt% sodium hydroxide/4.5wt% thiocarbamide/0.4wt% polyoxyethylene glycol (molecular weight 4000) mixed aqueous solution of 70g temperature for-8 ℃; And the kneading shear-mixed is even down to place-2 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 3
The 5.0g exsiccant cotton pulp dregs of rice (polymerization degree 500) and 70g 5.0wt% Lithium Hydroxide MonoHydrate/12.0wt% urea/5.5wt% polyoxyethylene glycol (molecular weight 150) mixed aqueous solution kneading shear-mixed under 0 ℃ are even; Then to wherein adding 5.0wt% Lithium Hydroxide MonoHydrate/12.0wt% urea/5.5wt% polyoxyethylene glycol (molecular weight 150) mixed aqueous solution of 30g temperature for-15 ℃; And the kneading shear-mixed is even down to place-8 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 4
The 5.3g exsiccant cotton pulp dregs of rice (polymerization degree 620) and 50g 3.5wt% Lithium Hydroxide MonoHydrate/6.5wt% thiocarbamide/0.3wt% polyoxyethylene glycol (molecular weight 1,000,000) mixed aqueous solution kneading shear-mixed under 15 ℃ are even; Then to wherein adding 3.5wt% Lithium Hydroxide MonoHydrate/6.5wt% thiocarbamide 0.3wt% polyoxyethylene glycol (the molecular weight 100 ten thousand) mixed aqueous solution of 50g temperature for-10 ℃; And the kneading shear-mixed is even down to place-4 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 5
The 17.5g exsiccant cotton pulp dregs of rice (polymerization degree 250) and 40g 9.5wt% sodium hydroxide/6.0wt% thiocarbamide/8.0wt% urea/3.0wt% polyoxyethylene glycol (molecular weight 2000) mixed aqueous solution kneading shear-mixed under 20 ℃ are even; Then to wherein adding 9.5wt% sodium hydroxide/6.0wt% thiocarbamide/8.0wt% urea/3.0wt% polyoxyethylene glycol (molecular weight 2000) mixed aqueous solution of 60g temperature for-12 ℃; And the kneading shear-mixed is even down to place-6 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 6
2.0g exsiccant wood pulps (polymerization degree 1500) and 30g 7.5wt% Lithium Hydroxide MonoHydrate/2.0wt% thiocarbamide/10.0wt% urea/2.5wt% polyoxyethylene glycol (molecular weight 6000) mixed aqueous solution kneading shear-mixed under 0 ℃ is even; Then to wherein adding 7.5wt% Lithium Hydroxide MonoHydrate/2.0wt% thiocarbamide/10.0wt% urea/2.5wt% polyoxyethylene glycol (molecular weight 6000) mixed aqueous solution of 70g temperature for-12 ℃; And the kneading shear-mixed is even down to place 0 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 7
8.0g exsiccant regenerated cellulose (polymerization degree 300) and 70g 6.0wt% sodium hydroxide/22.0wt% urea/6.0wt% polyoxyethylene glycol (molecular weight 400) mixed aqueous solution kneading shear-mixed under 0 ℃ is even; Be 6.0wt% sodium hydroxide/22.0wt% urea/6.0wt% polyoxyethylene glycol (molecular weight 400) mixed aqueous solution of 5 ℃ to wherein adding the 30g temperature then; And the kneading shear-mixed is even down to place 4 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 8
The 5.0g exsiccant cotton pulp dregs of rice (polymerization degree 500) and 60g 7.5wt% Lithium Hydroxide MonoHydrate/4.5wt% urea/3.5wt% polyoxyethylene glycol (molecular weight 400) mixed aqueous solution kneading shear-mixed under 5 ℃ are even; Then to wherein adding 7.5wt% Lithium Hydroxide MonoHydrate/4.5wt% urea/3.5wt% polyoxyethylene glycol (molecular weight 400) mixed aqueous solution of 40g temperature for-10 ℃; And the kneading shear-mixed is even down to place 10 ℃; Mierocrystalline cellulose can dissolve fully, obtains the cellulose solution of homogeneous transparent.This cellulose solution was at room temperature deposited 35 days and was not had tangible gelation.
Embodiment 9
The 125g exsiccant cotton pulp dregs of rice (polymerization degree 400) and 1000g 7.0wt% sodium hydroxide/12.0wt% urea/1.2wt% polyoxyethylene glycol (molecular weight 2000) mixed aqueous solution kneading shear-mixed under 5 ℃ are even; Then to wherein adding 7.0wt% sodium hydroxide/12.0wt% urea/1.2wt% polyoxyethylene glycol (molecular weight 2000) mixed aqueous solution of 2000g temperature for-12 ℃; And the kneading shear-mixed is even down to place 0 ℃, obtains the cellulose solution of homogeneous transparent.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 30 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 15 ℃ 15wt% sodium acetate aqueous solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 65 ℃ 5wt% sodium acetate aqueous solution; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.4cN/dtex and 7.3%.
Embodiment 10
165g exsiccant bamboo pulp (polymerization degree 500) and 1500g 9.5wt% sodium hydroxide/5.0wt% thiocarbamide/3.0wt% polyoxyethylene glycol (molecular weight 1000) mixed aqueous solution kneading shear-mixed under 10 ℃ is even; Then to wherein adding 9.5wt% sodium hydroxide/5.0wt% thiocarbamide/3.0wt% polyoxyethylene glycol (molecular weight 1000) mixed aqueous solution of 1500g temperature for-10 ℃; And the kneading shear-mixed is even down to place-4 ℃, obtains the cellulose solution of homogeneous transparent.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 0 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 5 ℃ 30wt% sodium chloride aqueous solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 60 ℃ 15wt% sodium chloride aqueous solution; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.3cN/dtex and 6.7%.
Embodiment 11
The 190g exsiccant cotton pulp dregs of rice (polymerization degree 600) and 900g 6.5wt% Lithium Hydroxide MonoHydrate/10.0wt% urea/0.8wt% polyoxyethylene glycol (molecular weight 500,000) mixed aqueous solution kneading shear-mixed under 25 ℃ are even; Then to wherein adding 6.5wt% Lithium Hydroxide MonoHydrate/10.0wt% urea/0.8wt% polyoxyethylene glycol (the molecular weight 50 ten thousand) mixed aqueous solution of 2100g temperature for-12 ℃; And the kneading shear-mixed is even down to place 0 ℃, obtains the cellulose solution of homogeneous transparent.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 20 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 15 ℃ 20wt% aqueous sodium persulfate solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 75 ℃ 3wt% aqueous sodium persulfate solution; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.7cN/dtex and 11.5%.
Embodiment 12
158g exsiccant wood pulps (polymerization degree 800) and 2100g 5.5wt% Lithium Hydroxide MonoHydrate/5.0wt% thiocarbamide/1.4wt% polyoxyethylene glycol (molecular weight 50,000) mixed aqueous solution kneading shear-mixed under 5 ℃ is even; Then to wherein adding 5.5wt% Lithium Hydroxide MonoHydrate/5.0wt% thiocarbamide/1.4wt% polyoxyethylene glycol (the molecular weight 5 ten thousand) mixed aqueous solution of 900g temperature for-12 ℃; And the kneading shear-mixed is even down to place-8 ℃, obtains the cellulose solution of homogeneous transparent.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 20 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 15 ℃ 20wt% aqueous sodium persulfate solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 85 ℃ pure water; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.8cN/dtex and 12.4%.
Embodiment 13
Method according to embodiment 5 prepares the solution that the 3525g cellulose concentration is 15wt%.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 15 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 20 ℃ 10wt% aqueous sodium persulfate solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 95 ℃ pure water; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.6cN/dtex and 8.1%.
Embodiment 14
Other are with embodiment 12, and different is, and at first to get into temperature from the stoste thread of spinning jet ejection be 30 ℃ 5wt% sodium phosphate aqueous solution.The breaking tenacity of gained regenerated cellulose fibre and elongation at break are respectively 2.4cN/dtex and 6.7%.
Embodiment 15
Method according to embodiment 6 prepares the solution that the 3060g cellulose concentration is 2wt%.This cellulose solution is after deaeration and filtering, and the spinning pack of sending into spinning machinery through volume pump carries out wet-spinning, and supplying to spin temperature is 10 ℃.At first getting into temperature from the stoste thread of spinning jet ejection is 15 ℃ 20wt% aqueous sodium persulfate solution; Through solidifying and stretch orientation before the cellulosic molecule hydrogen bond network does not fully form as yet; And then get into temperature and be 45 ℃ pure water; Through fully solidify regeneration, further behind the stretch orientation, successively through wash, oil, dry, coiling obtains regenerated cellulose fibre.The breaking tenacity of this regenerated cellulose fibre and elongation at break are respectively 2.5cN/dtex and 7.6%.
Comparative example 1
This comparative example is to adopt different dissolving methods that Mierocrystalline cellulose is dissolved; The proportioning of the used Mierocrystalline cellulose of dual mode, solvent and the consumption of solvent are all identical; But the consumption of cellulosic material is different, and the proportioning of solvent is referring to embodiment 1, and the concrete technology of dissolution mechanism is referring to embodiment 1 at twice; The solvent temperature of a dissolution mechanism is-10 ℃, and the result is as seeing table 1:
Table 1 dissolution mechanism is to the influence of cellulose dissolution
Can draw from table 1 result, solvent adds in the cellulose solution that this twice dissolution mechanism of dissolving cellulos obtain at twice, do not have undissolved Mierocrystalline cellulose, and the dissolved cellulose concentration is high, and what solution can be stable deposited 35 days.
Method to other embodiment is also carried out above-mentioned contrast, and the result matches with it.
Comparative example 2
This comparative example is that different solvents is adopted the comparison of identical dissolving method to cellulose dissolution; Solvent orange 2 A: the aqueous solution of 7.5wt% sodium hydroxide/11.0wt% urea; The aqueous solution of solvent B:7.5wt% sodium hydroxide // 1.5wt% polyoxyethylene glycol (molecular weight 800), solvent C: referring to the prescription of experimental example 1 solvent.The consumption of three kinds of solvents is identical, and used Mierocrystalline cellulose is also identical, but cellulosic consumption is different, and dissolving method is dissolving at twice, and dissolution process is with reference to experimental example 1, and the result is as seeing table 2:
Table 2 solvent is to the influence of cellulose dissolution
Can find out that from the result of table 2 when containing alkali, urea or thiocarbamide and terepthaloyl moietie simultaneously in the solvent, do not have undissolved Mierocrystalline cellulose in the gained cellulose solution, the dissolved cellulose concentration is also high, and solution kept stable in 35 days.
Method to other embodiment is also carried out above-mentioned contrast, and the result matches with it.
Claims (10)
1. the method for a dissolving cellulos comprises the steps:
Be under 0～25 ℃ the condition in temperature; Earlier that Mierocrystalline cellulose is even through mediating shear-mixed with the solvent of the solvent gross weight 30～70wt% that accounts for dissolving cellulos; And then add remaining, temperature solvent for-15～5 ℃ dissolving cellulos; And, be placed on that to mediate shear-mixed under-8～25 ℃ the temperature even, promptly obtain the homogeneous fibre cellulose solution.
2. method according to claim 1 is characterized in that, the solvent of described dissolving cellulos comprises following component:
The aqueous solution of polyoxyethylene glycol of urea and 0.4～6.0wt% that contains sodium hydroxide, the 8.5～22.0wt% of 6.0～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.4～6.0wt% that contains sodium hydroxide, the 3.5～6.5wt% of 8.5～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～5.5wt% that contains Lithium Hydroxide MonoHydrate, the 4.5～25.0wt% of 3.5～7.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.3～5.5wt% that contains Lithium Hydroxide MonoHydrate, the 2.5～6.5wt% of 3.5～7.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.2～5.0wt% that contains thiocarbamide, the 2.0～15.5wt% of sodium hydroxide, the 3.0～8.5wt% of 5.0～12.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.2～5.0wt% that contains thiocarbamide, the 0.5～15.0wt% of Lithium Hydroxide MonoHydrate, the 2.0～6.5wt% of 3.0～7.5wt%.
3. method according to claim 2 is characterized in that, the solvent of described dissolving cellulos comprises following component:
The aqueous solution of polyoxyethylene glycol of urea and 0.5～4.5wt% that contains sodium hydroxide, the 10.0～18.0wt% of 7.0～10.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.5～4.5wt% that contains sodium hydroxide, the 4.0～5.5wt% of 9.0～10.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.4～4.0wt% that contains Lithium Hydroxide MonoHydrate, the 6.0～20.0wt% of 4.0～6.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of thiocarbamide and 0.4～4.0wt% that contains Lithium Hydroxide MonoHydrate, the 3.0～5.5wt% of 4.0～6.5wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～3.5wt% that contains thiocarbamide, the 3.0～10.5wt% of sodium hydroxide, the 4.0～6.5wt% of 7.0～10.0wt%;
Perhaps, the aqueous solution of polyoxyethylene glycol of urea and 0.3～3.5wt% that contains thiocarbamide, the 2.0～10.0wt% of Lithium Hydroxide MonoHydrate, the 3.0～5.5wt% of 3.5～6.0wt%.
4. method according to claim 1 and 2 is characterized in that, the number-average molecular weight of described polyoxyethylene glycol is 150～1000000, and more preferably the molecular weight of polyoxyethylene glycol is 800～500000.
5. method according to claim 1 and 2 is characterized in that, described Mierocrystalline cellulose comprises bamboo pulp, wood pulps or the cotton pulp dregs of rice, perhaps viscose fiber, lyocell fiber and non-woven fabrics thereof.
6. a method for preparing regenerated cellulose fibre comprises the steps:
(1) cellulose solution gets spinning solution after deaeration; Stoste through the spinning jet ejection is solidified in first precipitation bath; Described first precipitation bath is a kind of in 5～30wt% aqueous sodium persulfate solution, 5～25wt% sodium acetate aqueous solution, 10～30wt% sodium chloride aqueous solution or the 5～25wt% sodium phosphate aqueous solution, and temperature is 5～30 ℃;
(2) solidify and in second precipitation bath, solidify through step (1) through the fiber after the drawing-off; Through further obtaining cellulosic fibre through follow-up processing again after the drawing-off; Wherein, Described second precipitation bath be mass percent concentration be 2～15wt% aqueous sodium persulfate solution, sodium acetate aqueous solution, sodium chloride aqueous solution or sodium phosphate aqueous solution in a kind of, perhaps be pure water, coagulation bath temperature is 45～95 ℃.
7. method according to claim 6 is characterized in that, first precipitation bath is 5～30wt% aqueous sodium persulfate solution; More preferably first precipitation bath is 10～25wt% aqueous sodium persulfate solution.
8. according to claim 6 or 7 described methods, it is characterized in that second precipitation bath is 3～10wt% aqueous sodium persulfate solution or pure water; Most preferably second precipitation bath is a pure water.
9. method according to claim 6 is characterized in that, the temperature of second precipitation bath is 55～90 ℃; Most preferably the temperature of second precipitation bath is 65～85 ℃.
10. according to each described method of claim 6-9, it is characterized in that cellulosic content is 2～15wt% in the cellulose solution, the temperature of cellulose spin dope is 0～30 ℃.
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| CN115537956A (en) * | 2022-09-28 | 2022-12-30 | 百事基材料（青岛）股份有限公司 | Lyocell macrobiological fiber containing bioactive components and preparation method thereof |
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