EP1040214B1 - Auxiliary agent for the production of cellulose fibers - Google Patents

Abstract

Methods of preparing cellulose materials, which methods comprise (a) reacting a cellulosic material with a first basic component to form alkli cellulose; (b) reacting the alkali cellulose with carbon disulfide and a second basic component to form a cellulose xanthate solution; and (c) extruding the cellulose xanthate into an aqueous coagulation bath; wherein a reaction product of an epoxide of the general formula (I):wherein R1 represents a linear or branched aliphatic alkyl group having from about 1 to about 22 carbon atoms, and an amine compound of the general formula (II):wherein R2 and R3 each independently represent a substituent selected from the group consisting of -CnH2n-O)m-H, alkyl groups having from about 1 to about 22 carbon atoms, and hydrogen, wherein n represents 2 or 3 and m represents a number of from about 1 to about 20; is present in at least one of the cellulose xanthate solution and the aqueous coagulation bath, are described. Cellulose xanthate solutions and aqueous coagulation baths containing such reaction products are also described.

Description

The present application relates to the use of end group capped alkoxylated amines as auxiliaries in the production of cellulose fibers after Viscose process and a process for the production of cellulose fibers according to the Process viscose.

The large-scale production of cellulose fibers mainly takes place after Viscose. The pulp is first in cellulose exanthate, which so-called viscose, transferred and pressed into an acidic precipitation bath. By the Contact with the acidic solution, the xanthate is precipitated and saponified the cellulose is released in the form of a filament.

It has been shown that the addition of auxiliaries, the so-called modifiers, the mechanical quality of the spun fibers for viscose or spinning solution can significantly improve. The modifiers slow down xanthate decomposition and thus enable the formation of a uniform fiber structure (see Z.A. Rogowin, chemical fibers, Georg Thieme Verlag, Stuttgart, 1982, pages 123 ff).

Various classes of substances are known as modifiers, e.g. B. quaternary ammonium bases, N-substituted dithiocarboxylic acids, polyethylene glycols and
aliphatic monoamines and especially oxyethylated amines and amides or their derivatives. DE 28 37 766 describes, for example, alkoxylation products of a polyhydric alcohol and / or a dibasic amine as modifiers. DE 29 21 314 describes a process for producing crimped cellulose fibers, the modifiers used being, inter alia, ethoxylated fatty acid amines having 8 to 20 carbon atoms. Furthermore, alkylamine glycol ethers are widely used as modifiers in the production of viscose. These compounds are prepared by reacting alkoxylated amines with alkyl halides, preferably alkyl chlorides, in the sense of a Williamson ether synthesis. However, this inevitably releases significant amounts of salts, the disposal of which is expensive and causes environmental problems. In some cases, residues of the alkyl chlorides remain in the reaction product, which may have to be removed by a complex and expensive cleaning process.

There is therefore a need for modifiers, the same or better Have properties than the compounds known in the prior art and the are manufactured using simple processes that are less harmful to the environment can. Particular attention should be paid to the use of chlorine chemicals can be completely dispensed with.

It has been found that certain end group capped nonionic surfactants Base of alkoxylated amines which have the properties mentioned above.

in der R¹ für einen linearen oder verzweigten aliphatischen Alkylrest mit 1 bis 22 C-Atomen steht mit Verbindungen der Formel (II)

in der R² und R³ unabhängig voneinander für einen Rest (C_nH_2n-O)_m-H oder einen linearen oder verzweigten, gesättigten oder ungesättigten Alkylrest mit 1 bis 22 C-Atomen oder Wasserstoff stehen, n den Wert 2 oder 3 hat und m eine Zahl zwischen 1 und 20 bedeutet, als Hilfsmittel bei der Herstellung von Cellulosefasern nach dem Viskoseverfahren.In a first embodiment, the present application relates to the use of reaction products of the nucleophilic ring opening of epoxides of the formula (I)

in which R ^{1 represents} a linear or branched aliphatic alkyl radical having 1 to 22 carbon atoms with compounds of the formula (II)

in which R ² and R ³ independently of one another represent a radical (C _n H _2n -O) _m -H or a linear or branched, saturated or unsaturated alkyl radical having 1 to 22 C atoms or hydrogen, n is 2 or 3 has and m is a number between 1 and 20, as an aid in the production of cellulose fibers by the viscose process.

The ring opening products are known compounds, which according to the usual Methods of organic chemistry can be synthesized. The synthesis of such Connections are usually carried out by reacting the epoxides of the formula (I) with Compounds of formula (II) in the presence of suitable, preferably alkaline Catalysts, e.g. Potassium or lithium hydroxide. Potassium hydroxide is preferred used. By a nucleophilic attack of the oxygen atom of the compounds of the Formula (II) on one of the epoxy carbon atoms opens the ring and it forms α-hydroxy ether. Details of this reaction can be found, for example, in the article by W. Stein in fats, soaps, paints, No. 2, 84th year 1992, page 51 and the literature cited there.

The ring opening reaction takes place preferably under anhydrous conditions Normal pressure instead. Depending on the type of starting materials used, reaction temperatures between 100 and 180 ° C. It is preferred that the reaction in the Temperature range from 140 to 160 ° C to perform.

The epoxides of the formula (I) are known compounds which are prepared by epoxidizing alpha-olefins which are obtained, for example, by the shop process. Typical examples are the epoxides of Octen-1, Decen-1, Dodecen-1, Tetradecen-1, Octadecen-1 or Octadecen-9. Epoxides of the formula (I) are preferred. in which R ^{1 is} a linear aliphatic alkyl radical having 8 to 14 carbon atoms.

The compounds of the formula (II) are also known. It is ethanol or propanolamines and their alkoxylation products. These can, for example by alkoxylation of mono-, di- or trialkanolamines by customary methods be preserved. As alkoxides, ethylene oxide (EO) or propylene oxide (PO) or Mixtures of these alkoxides can be used. Such compounds are preferred of the formula (II) in which m is a number between 10 and 20 and preferably 12 to 18 means. Those compounds are particularly preferred which only Contain ethylene oxide groups. Such ring opening products are preferred used in the preparation of which, if appropriate, ethoxylated trialkanolamines, preferably triethanolamine can be used. Other suitable connections can be alkoxylated by other alkanolamines, e.g. 2- (dibutylamino) ethanol, 2- (diethylamino) ethanol, 2- (methylamino) ethanol, 2-ethylaminoethanol, 2-dimethylaminoethanol, Ethanolamine or diethanolamine.

The molar ratio between the epoxy (I) and the compound of formula (II) at the ring opening reaction is preferably between 1: 2 and 1: 1 Ring opening products typically have hydroxide numbers of at least 160, preferably from at least 180.

The ring opening products are manufactured without the addition of chlorine chemicals. Also there is no salt load when opening the ring, e.g. at Williamson's Ether synthesis occurs.

The products obtained by ring opening can be used as modifiers of both Viscose solution are added, as well as the acidic precipitation bath into which the viscose is pressed. The ring opening products are preferably in quantities between 1 and 5% by weight, based on those contained in the viscose or in the precipitation bath Cellulose added.

By using the ring opening products as modifiers in the Viscose solution makes spinning easier, one continues to observe one reduced clogging of the spinnerets. Are the ring opening products as Modifiers used in the acidic precipitation bath are observed to be more uniform Decomposition of xanthate cellulose and slowing of thread formation. This leads to threads with higher mechanical resilience. At the same time, the failures prevents inorganic salts.

The modifiers of the invention are suitable for use in all of them Processes known to those skilled in the art for producing cellulose fibers according to the Viscose.

a) Bildung von Alkalicellulose durch Umsetzung von Zellstoff mit Alkalilaugen

b) Umsetzung der Alkalicellulose mit Schwefelkohlenstoff und einer Lauge unter Ausbildung einer Xanthogenatlösung und

c) Verspinnen der Xanthogenatlösung durch Spinndüsen in ein wäßriges Fällbad enthaltend eine Protonensäure sowie Metallsalze, wobei sich unter Zersetzung des Xanthogenats ein Cellulosefaden bildet,

wobei man die oben beschriebenen Reaktionsprodukte der Xanthogenatlösung und/oder dem Fällbad in wirksamen Mengen als Modifikatoren zusetzt.Another object of the present application relates to a process for the production of cellulose fibers by the viscose process, comprising the steps

a) Formation of alkali cellulose by reacting pulp with alkali eyes

b) reaction of the alkali cellulose with carbon disulphide and an alkali to form a xanthate solution and

c) spinning the xanthate solution through spinnerets into an aqueous coagulation bath containing a protonic acid and metal salts, a cellulose thread being formed with the decomposition of the xanthate,

wherein the above-described reaction products of the xanthate solution and / or the precipitation bath are added in effective amounts as modifiers.

In the context of this application, the viscose process is used industrially Process of cellulose fiber production understood, as described for example in Z.A. Rogowin, chemical fibers, Georg Thieme Verlag, Stuttgart, 1982, pages 67 to 152 is described.

To carry out the method according to the invention, in method step a) Cellulose, for example in the form of pressed sheets, rolled goods, flakes or squeezed, undried pulp, reacted with an alkali, whereby in known form first the alkali cellulose. Any can be used as lyes basic systems are used, especially aqueous alkali, such as potassium or Sodium hydroxide solution. The concentration usually amounts to 15 to 30% by weight Base, based on the total weight of the lye.

After pressing off the excess lye, the alkali cellulose is obtained. Process step b) follows, which comprises the individual steps of pre-ripening, xanthation with carbon disulphide, dissolving the xanthate in alkali metal solution, ripening and deaerating and leading to the spinnable viscose solution. Details of this process are described, for example, in the above-mentioned publication by ZA Rogowin, pages 97 to 119.
In the process according to the invention, the modifiers described above are added to the xanthate solution during the dissolution of the cellulose xanthate in alkali metal hydroxide solution and / or during the maturation. The amount of the modifiers is preferably between 1 and 5% by weight, based on the cellulose contained in the solution.

The ripened xanthate solution, process step c), is then spun by pressing the solution, which was previously filtered and tempered, through a Spinneret with essentially round nozzle holes in the precipitation bath. Examples of this are spinnerets with 250 to 30,000 holes and a single diameter one Hole from 35 to 100 µm. In the precipitation bath, the xanthate coagulates into threads and becomes using a protonic acid to regenerate cellulose, salt and carbon disulphide hydrolyzed. The carbon disulfide is returned to the process. As Protonic acid can be organic acids such as acetic acid or mineral acids such as salt, nitrate or sulfuric acid can be used. It is preferred to concentrate Sulfuric acid used. The precipitation bath contains certain acids in addition to the acid Metal salts that can slow down xanthate coagulation. examples for such salts are magnesium, aluminum, iron and in particular zinc salts. The Salts are usually used as chlorides, nitrates or sulfates. The The concentration of the salts is usually between 2 to 10 g / l.

In the process according to the invention, the precipitation bath is described as above Modifiers added, preferably in amounts of 1 to 5% by weight, based on the contained cellulose. The precipitation bath can be used in addition to those described above Modifiers, the acid and the metal salts are still further known to the person skilled in the art Contain aids, e.g. Formaldehyde or other modifiers. The so won Cellulose filaments are then spun, cleaned and in a manner known per se further treated.

The inventive method is characterized in that at least one of the two process steps b) or c) modifiers of the type described above be used. Preferably, the method is carried out so that the Modifiers only of the viscose solution before spinning, i.e. in step b), be added.

example

1226.7 g (1.70 mol) of triethanolamine ethoxylate (17 EO) were treated under a nitrogen atmosphere with 266.6 g (1.36 mol) of α-lauryl epoxide and 12.2 g (0.065 mol) of potassium hydroxide in the form of a 30% by weight mixed methanolic solution and stirred at 160 ° C for eight hours. The mixture was then cooled to 80 ° C. and 14.9 g (0.15 mol) of H ₂ O _{2 were} added. The reaction product (1301.5 g) was obtained in the form of an orange-brown, clear liquid after removal of the water. Hydroxide number = 182, alkali number = 0.2, amine number = 56, Lovibond color value (5 ^¼ inch): 5 red, 30 yellow.

Claims (7)

1. The use of reaction products of the nucleophilic ring opening of epoxides of the formula (I)

   

   where R¹ is linear or branched aliphatic alkyl of 1 to 22 carbon atoms, with compounds of the formula (II)

   

   where R² and R³ are independently (C_nH_2n-O)_m-H or linear or branched saturated or unsaturated alkyl of 1 to 22 carbon atoms or hydrogen, n is 2 or 3 and m is between 1 and 20,
   as auxiliary agent for the production of cellulose fibers by the viscose method.
2. The use defined in claim 1, characterized in that R² and R³ in the compounds of the formula (II) are radicals of the formula (C_nH_2n-O)_m-H.
3. The use defined in claim 1 or 2, characterized in that n in the compounds of the formula (II) is 2.
4. The use defined in any of claims 1 to 3, characterized in that m in the compounds of the formula (II) is between 12 and 18.
5. The use defined in any of claims 1 to 4, characterized in that R¹ in the formula (I) is linear alkyl of 8 to 14 carbon atoms.
6. The use defined in any of claims 1 to 5, characterized in that the reaction products have hydroxide (OH) numbers of at least 160.
7. A method for producing cellulose fibers according to the viscose method, comprising the steps of

   a) forming alkali cellulose by reacting pulp with alkali metal hydroxide solution

   b) reacting the alkali cellulose with carbon disulfide and a lye to form a xanthate solution and

   c) spinning the xanthate solution through spinnerets into an aqueous coagulation bath containing a protic acid and metal salts to decompose the xanthate and form a cellulose threadline,

   characterized in that the reaction products set forth in claim 1 are added to the xanthate solution and/or the coagulation bath in effective amounts as modifiers.