Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
  • D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
  • D01F2/28—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate

Definitions

• the invention relates both to a process for the production of water-insoluble fibers from cellulose monoesters of maleic acid, succinic acid and phthalic acid with an extremely high absorption capacity for water and physiological liquids, and to the fibers themselves.
• Hydrophilically modified viscose fibers are known under the trade name Viscosorb (see Lenzinger reports, Issue 51, (1981), pages 34 ff). Their water retention capacity of 140 to 150% or 200 to 210% is not inconsiderably increased compared to that of normal viscose (80 - 90%), but appears to be in need of improvement.
• Quite water-insoluble cross-linked fibrous salts of carboxymethyl cellulose are known from DT-OS 19 12 740. They can have a water retention value of over 3,000. Even so that these fibrous salts are only 5 - 16% soluble, the fibrous water-soluble NaCMC salts initially made from cellulose must be crosslinked with epichlorohydrin or formaldehyde. The fibrous state of the end product only results from the specified short-fiber form of the chemical pulp to be converted, which generally has an average fiber length of 1 - 2.4 mm. The production of normal continuous fibers with targeted mechanical properties is naturally not possible in this way.
• cellulose acetophthalates which are obtained from hydrolyzed cellulose acetate and an excess of phthalic anhydride in acetone or dioxane (Ullmann, 4th edition, volume 9, page 237). This creates esters of phthalic acid with a free carboxyl group. These products are suitable as water- or alkali-soluble textile sizes and are also used as antistatic agents in film coating.
• the present invention provides new water-insoluble fibers which represent an interesting enrichment of the corresponding products of the prior art, in particular because of their high and extremely variable absorption capacity for water and physiological liquids.
• the preservation of water-insoluble fibers of the above-mentioned type with an extremely high absorption capacity for water and physiological liquids depends on several variables which are decisively influenced by the constitution of the respective macromolecular substance. To obtain fibers with satisfactory mechanical properties, it is essential to ensure a sufficiently high degree of polymerization. It is therefore important that the activated cellulose initially produced has an average degree of polymerization of 300 to 800, preferably 350-650, which must be largely maintained during the reaction with dicarboxylic acid anhydrides. To avoid degradation of the cellulose, the reaction temperature and reaction time must be coordinated.
• esterification catalysts known per se, acids, such as methanesulfonic acid, perchloric acid, formic acid and sulfuric acid, or acid chlorides, such as acetyl chloride and propionyl chloride, are suitable for the esterification reaction. These acidic esterification catalysts can be used in amounts of about 2 to 10 percent by weight, based on the amount of acid anhydride.
• basic esterification catalysts are also well suited for the esterification reactions in question, especially since they counteract cellulose degradation.
• Examples include the following tertiary amines: 4-N, N-dimethylaminipyridine, collidine, pyridine and triethylamine.
• Such basic esterification catalysts based on the acid anhydride, are added in equimolar amounts in order to bind the acids released during the reaction.
• the fibrous quaternary ammonium salts obtained after spinning can easily be converted into alkali metal salts or into secondary or tertiary ammonium salts by the methods described below.
• Basic salts of monocarboxylic acids such as sodium acetate, potassium acetate, sodium propionate, potassium propionate, sodium butyrate and potassium butyrate are particularly suitable as esterification catalysts.
• these Salts based on the acid anhydride, are used in amounts of 2 to 10% by weight, preferably 5 to 10% by weight.
• alkali metal acetates in amounts of 2 to 10% by weight, based on the dicarboxylic acid anhydride used, has proven to be particularly advantageous.
• the absorption capacity for water and physiological liquids is shown below by the parameters water retention capacity (WRV) and retention capacity of synthetic urine (SURV).
• the water retention capacity according to DIN 53 814 is a measure of the water retained in the individual fibers after extensive immersion in water and subsequent defined centrifugation. The same applies to the retention capacity of synthetic urine, which was measured according to the same regulation.
• the cellulose monoester fibers of maleic acid in which the hydroxyl hydrogen of the carboxyl group is not replaced by an alkali metal, have a high water retention capacity (WRV) if their degree of esterification is between about 0.4 and 1.3.
• WRV water retention capacity
• DS degree of esterification
• the WRV value is approximately 200%. He passes through a maximum at a DS of approximately 0.7 with a WRV value of 1100%, and then falls back to a WRV value of 25O% up to a degree of esterification of 1.2, with the WRW values at even higher degrees of esterification continue to sink.
• unneutralized cellulose monoester fibers of maleic acid with a degree of esterification of 0.4 to 1.3 is one of the preferred embodiments of the invention.
• the p H value of such fibers is outside the alkaline range, which is essential in any case for the areas of hygiene and medicine.
• the cellulose monoester fibers of succinic acid in which the hydroxyl hydrogen of the carboxyl group is not partially or completely replaced by an alkali metal, already have a good water retention capacity of 220% at a degree of esterification of about 0.3. From then on, the WRV value rises in such a surprising manner that the water retention capacity is already almost 5300% at a DS of 0.67. This astonishingly high WRV value drops again with higher degrees of esterification. It reaches 1900% with a DS of 1.7.
• the production of unneutralized, ie not in salt form, cellulose monoester fibers of succinic acid with a degree of esterification of 0.3 to 1.7 is accordingly a further preferred embodiment of the invention.
• the cellulose monoester fibers of phthalic acid in which the hydroxyl hydrogen of the carboxyl groups is not partially or completely replaced by an alkali metal, have a relatively low WRV value at low degrees of esterification, for example a WRV value of 125% at a DS of 0.20 continues to decrease with increasing DS values.
• a substantial increase in the water retention capacity is achieved according to the invention by converting them into the corresponding fibrous salts in an essentially organic solvent by reaction with alkali metal hydroxides and / or alkali metal alcoholates or ammonia or primary or secondary amines.
• Alcoholic alkali metal hydroxide solutions which are prepared by dissolving NaOH, KOH, LiOH or NH 3 in the corresponding alcohols, such as methanol, ethanol, propanol and butanol, optionally with the use of small amounts of water, are particularly suitable for the implementation of the cellulose monoester fibers.
• the neutralization should take place at a temperature of 10 to 25 ° C.
• the corresponding bicarbonates or carbonates in conjunction with low water additions to the alcohols used can also be used for this purpose.
• primary or secondary amines such as diethylamine, propylamine and ethanolamine, are also suitable for the reaction.
• solubilizers small amounts of water, usually about 10 to 30% by weight, should also be added as solubilizers. Otherwise, the most suitable amount of water added can easily be determined by a person skilled in the art by simple experiments, since the upper limit is only on the water swelling capacity of the fibers in question, which in turn is dependent on the degree of esterification.
• Substantially completely neutralized water-insoluble cellulose monoester fibers of phthalic acid with an extremely high absorption capacity for water and physiological liquids can be described in the manner and Only produce in the narrowly limited range of esterification from 0.1 to 0.4.
• the WRV value increases from 100 to about 4,000%. With higher degrees of esterification, the fibers become water-soluble.
• water-insoluble fibers whose water retention capacity is several times that of the corresponding acidic cellulose monoester fibers can also be produced from the acidic cellulose monoester fibers of maleic acid and succinic acid by completely neutralizing the carboxyl groups with alkali metal salts.
• the manufacturability of such fibers is tied to the narrowly limited degree of esterification range from 0.1 to 0.4. Above a degree of esterification of about 0.4, the fibers lose the desired property of being water-insoluble.
• the production of essentially neutralized cellulose monoester fibers of maleic acid, succinic acid and phthalic acid, which have a degree of esterification of 0.1 to 0.4, represents a further preferred embodiment of the invention.
• Such fibers can be used advantageously for the production of absorbent fabrics, such as diapers, wipes and haze filters.
• the fibers according to the invention have fiber strengths of 4-20 cN / tex, preferably 6-15 cN / tex, elongations of 4-20%, preferably 6-16%, and a water retention capacity of> 200%, preferably> 300% , which can generally be increased in the manner described to a WRV value of a few thousand percent.
• the water-insoluble fibers according to the invention also have an increased water absorbency (WSV).
• WSV water absorbency
• the fibers according to the invention are spun from cellulose monoesters of maleic acid, succinic acid and phthalic acid by conventional wet spinning processes and with conventional devices of this type.
• wet spinning the cellulose monoester solution prepared in this way is pressed out through nozzles with fine bores into a suitable coagulation bath, for example an alcohol bath kept at room temperature.
• Suitable coagulants are, for example, the alcohols methanol, ethanol, propanol and butanol, ketones, such as dimethyl ketone, methyl ethyl ketone, diethyl ketone, dipropyl ketone and dibutyl ketone, and ethers, such as dipropyl ether, d ibutyl ether, diisoamyl ether and dioxane.
• ketones such as dimethyl ketone, methyl ethyl ketone, diethyl ketone, dipropyl ketone and dibutyl ketone
• ethers such as dipropyl ether, d ibutyl ether, diisoamyl ether and dioxane.
• the development of maximum fiber properties can be supported by running the threads combined to form a spun cable through a series of washing baths which contain the abovementioned solvents and, if appropriate, inorganic salts, in order to remove residues of the solvents used and L iCl. Simultaneously, a drawing can be connected to the post-treatment, the ge the setting of the respective desired fiber properties - equips.
• the Verstreckun g s wool can in this case from 1: 1 to 3: be varied. 1
• the cellulose monophthalate fibers obtained in this way have the following properties:
• the fibrous sodium salt of cellulose monophthalate has the following swelling values:
• the cellulose monophthalic acid esters listed in Table 1 are produced in principle by the same method as that given in Example 1. The same applies to their further processing into the claimed saline fibers.
• the cellulose maleinate fibers obtained have the following properties:
• the cellulose maleate fibers are converted to the ammonium salt.
• the fibrous cellulose maleinate salts obtained in this way have the following swelling values:
• cellulose monoesters of maleic acid were made and spun into fibers based on the procedure of Example 9 and the reaction conditions of Table 2. Water was used as the coagulant for weakly swelling cellulose derivatives (WRV: ⁇ 200%) and for strongly swelling (WRV:> 200%) ethanol.
• the resulting cellulose succinate fibers have the following properties:
• the cellulose succinate fibers produced in this way have the following properties:
• the fibrous sodium salt of the cellulose succinic acid ester has the following properties:
• 16.2 g (0.1 mol) of cellulose are dissolved in 278.4 g (3.2 mol) of technical dimethylacetamide and 29 g (0.68 mol) of LiCl.
• 6.1 g (0.05 mol) of 4-N, N-dimethylaminopyridine and 5 g (0.05 mol) of succinic anhydride are added to the cellulose solution in succession. The mixture is first heated at 40 ° C. for 5 hours, then stirred at room temperature for 15 hours and then precipitated with ethanol, washed and dried.
• the short-fiber cellulose monoester of succinic acid produced in this way has the following properties:
• the cellulose ester obtained has a degree of esterification of 0.28.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

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• 1983
  • 1983-04-02 DE DE3312022A patent/DE3312022A1/de active Granted
• 1984
  • 1984-01-20 AT AT84100623T patent/ATE42352T1/de not_active IP Right Cessation
  • 1984-01-20 EP EP84100623A patent/EP0126838B1/fr not_active Expired
  • 1984-01-20 DE DE8484100623T patent/DE3477815D1/de not_active Expired
  • 1984-02-20 CA CA000447787A patent/CA1229208A/fr not_active Expired
  • 1984-03-30 JP JP59061317A patent/JPS59187612A/ja active Pending
• 1986
  • 1986-03-03 US US06/837,311 patent/US4734239A/en not_active Expired - Fee Related

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