USE OF AN ALKOXYLATED POLYAMINE SURFACTANT AS A VISCOSE SPIN BATH ADDITIVE

Abstract: The present invention relates to a method of reducing the clogging of nozzles and slits and diminishing the formation of deposits in the spin bath system in the process of making viscose filamentary and film materials by using an alkoxylated polyamine surfactant having the formula (I): RNA-(-CnH2nNA-)-x-1A where R represents a hydrogen or an alifatic group with 1-24 carbon atoms, each A represents a hydrogen, an aliatic group with 1-24 carbon atoms, or H(OCmH2m)y-groups, where m is a number from 2-3, n is a number from 2-3, x is 4-8, with the proviso that the number of H(OCmH2m)y-groups are from 1 to x+1, and the total number of carbon atoms in the aliphatic groups is from 8 to 45. The alkoxylated polyamine surfactant has an excellent anticlogging effect, since it is a good dispersant and prevent or reduce precipitation in the spin bath. In addition it is very stable.

Description: USE OP AN ALKOXYLATED POLYAMINE SURFACTANT AS A VISCOSE SPIN BATH ADDITIVE The present invention relates to a method of reducing the clogging of nozzles and slits and diminishing the formation of deposits in the spin bath system in the process of making viscose filamentary and film materials by using an alkoxylated polyamine surfactant. When regenerating cellulose material in an acidic spin bath containing zinc sulphate, disturbancies frequently occur due to the presence of clogging material. The origins of the clogging material are different. One and the most important source are solid by-products, i.e. elementary sulphur and zinc sulphide, which are formed when the dis- solved xanthogenated celluloses are regenerated to cellulose and carbon disulphide. Other examples of clogging byproducts are hemicelluloses and resins derived from the cellulosic raw material itself and transfered to the spin bath where they cause deposits. One method of reducing these disadvantages is to add cationic surface active compounds to the spinning baths. Thus, in Japanese Patent No. 48006409 it is suggested to add N,N' -polyoxyethylene-N-long chain-alkyl alkylene-diamines and N,N' ,N' ' -polyoxyethylene-N-long chain- alkyl alkylene-triamines into the spin bath as dispersants for sulphur particles which cause blockages in spinning nozzles. The long-chain alkyl group contains from 10 to 20 carbon atoms. The number of oxyethylene groups are from 1 to 8 for each substitution position and their sum is from 2 to 10. However, these additives have a rather limited ability to disperse sulphur, especially when the amounts thereof is high. In Japanese Patent Application No. 54101916 it is suggested to add polyoxyethylene alkyl mono- and diamide polyalkylene polyamines to further reduce the clogging of nozzles. Examples of the used polyalkylene polyamines are triethylene tetramine and tetraethylene pentamine. The number of carbon numbers in the fatty acids used for pre- paring the said compounds is preferably from 12 to 22, while the number of groups derived from ethylene oxide in the molecule is from 6 to 12. Although these polyamines have a good dispersing effect they have a serious drawback since they are not stable in hot acid solutions and are hydrolyzed at high temperature in the spin bath. Consequently, after some time their effect is essentially reduced. The degradation of the additive can be compensated by addition of higher dosages of the additives. However in practice the resulting products of the hydrolysis, i.e. the fatty acids produced especially during reconditioning of the spin bath, enhances the clogging. Together with elementary sulphur and/or zinc sulphide and resins they form black particles, which are very difficult to disperse. It has now been found that not only the disturbancies of clogging materials in the spin bath are essentially diminished but also the quality of the fibers formed in the spin bath is improved by using an alkoxylated polyamine surfactant having the formula RNA C n H 2n NA)- x . 1 A (I) where R represents a hydrogen or an alifatic group with 1-24 carbon atoms, each A represents a hydrogen, an alifatic group with 1-24 carbon atoms, or H(OC m H 2m ) y -groups , where m is a number from 2-3, and y is a number from 1 to 5 , n is a number from 2-3, x is 4-8, with the proviso that the number of H (0C m H 2m ) y -groups are from 1 to x+1, and the total number of carbon atoms in the aliphatic groups is from 8 to 45, as a viscose spin bath additive. The alkoxylated polyamine surfactant has an excellent anticlogging effect, since it is a good dispersant and prevent or reduce precipitation in the spin bath. In comparison with the diamines and triamines disclosed in JP 48006409 the anticlogging and dispersing effects are essentially improved. In addition it is very stable in comparison with the amide compounds disclosed in JP Patent Application No. 54101916. Since the additive keeps the openings in the spinneret free from clogging materials, the filaments and films formed collect less solid particles, whereby the discolouration is reduced and the fiber or film strenght improved. In addition the aintainance of the spin bath is also simplyfied. Since the alkoxylated polyamine surfactant has a high stability in ordinary working-up- processes of the spin bath, the spin bath solution can be recirculated after the removal of an excess of the byproducts including sodium sulphate formed in the spin bath. The amount of the alkoxylated polyamine surfactant in the spin bath may be varied within wide limits but is normally added in an amount of 0.5-5000 ppm, preferably from 2 to 1000 ppm, to a spin bath containing 5-15% by weight H 2 S0 4 , 15-30% by weight of Na 2 S0 4 and 0-7% by weight of ZnS0 4 . The alkoxylated polyamine surfactant with formula I preferably contains one or two aliphatic groups, R and A, with a total of 8 to 40 carbon atoms, preferably between 10 and 36 carbon atoms. Preferably R is a hydrocarbon group with 8-24 carbon atoms, and most preferably a hydrocarbon group with 10-22 carbon atoms, while m is 2 and the total number of OC 2 H 4 -units are from 4 to 30. Most preferred alkoxylated polyamine surfactants of the formula I are those having the formula RNA C 3 H 6 NA 7 - x . 1 A (II) where R has the meaning mentioned in formula I, x is 4-6 and A is hydrogen or the group (C 2 H 4 0) y H, where y has the meaning mentioned in formula I and the total number of C 2 H 4 0-units is from 4 to 15. These additives are easy to produce and have excellent dispersing ability. The present invention also relates to a process for regeneration of cellulose from a viscose solution, in which process the viscose solution is brought into contact with a spin bath containing from 0.5 to 5000 ppm of an alkoxylated polyamine surfactant according to formula I. Preferably the alkoxylated polyamine surfactant has the formula II. The spin bath has normally a temperature of from 40°C to 60°C and contains in addition to the alkoxylated polyamine surfactant from 5 to 15% by weight of H 2 S0 4 , from 15 to 30% by weight of Na 2 S0 4 and from 0-7% by weight of ZnS0 4 . The cellu- lose regenerated may have the form of fibers or films or any other conventional shape. The invention is further illustrated by the following examples. Example 1. Degradation kinetics of two spin bath additives were evaluated in a spin bath with the composition 9,5% H 2 S0 4 , 23% Na 2 S0 4 , 0,4% ZnS0 4 and 67,1% H 2 0 at different temperatures stated in the tables below. One of the additives was an amide condensate of tetraethylene pentamine and a tallow fatty acid ethoxylated with 10 moles ethylene oxide per mol amide, hereinafter referred to as Compound B. Compound B is a typical representative of an additive in the Japanese Patent Application No. 54101916. The other additive was an N,N' ,N* ' ,N' ' ' -polyoxy- ethylene-N- (tallow alkyl) tetraamine with 7.5 moles oxyethy- lene per mole tetraamine. This additive is a typical representative of an alkoxylated polyamine surfactant according to this invention. The content of Compound B and Compound 1 in the spin bath solutions were analyzed by using the dye Orange II. This dye and the cationic surfactant were reacted and the complex formed was extracted into chloroform. Then the amount of the complex in the chloroform phase was spectro- fotometrically determined at a wave length of 488 nm. The data obtained are presentated below in Tables 1 and 2. The figures show the residual non-degraded amount of Compound B and Compound 1 in % . From the results it is evident that the stability in the hot spin bath solution is much lower for the amide type of spin bath additive (Compound B) than for the additive according to the invention (Compound 1) . Examples 2-4. Precipitation prevention and dispersing capacities of some spin bath additives were determined according to the following procedure. 21 ml of a solution containing 0.25 M Na 2 S 2 0 3 , 0.15 M Na 2 CS 3 and 0.25 M Na 2 S was dropwise added during stirring into a polypropylene vessel containing 1 liter of a spin bath. The spin bath contained 10% by weight H 2 S0 4 , 20% by weight Na 2 S0 4 , 1% by weight ZnS0 4 , 69% by weight H 2 0 and a dispersing additive from 0-25 ppm. Its temperature was 50°C. The stirrer was made of glass with a propellar of platinum. After the addition the transmittance of the bath was measured after predetermined times in a spectrophotometer at the wave length of 450 nm in a glass cuvette. During the whole test the stirring was kept constant at 300 rpm. After 270 minutes the test was interrupted and the weight of the stirrer was measured in order to determine the amount of material precipitated on the stirrer. The following dispersing additives were used. Compound A. A compound having the formula (E0) X H (E0) y H C 18 -alkyl-N-C 3 H 6 N (E0) z H where EO is ethyleneoxy and the sum of x, y and z is 10, in accordance with the amine compounds disclosed in the Japanese Patent No. 48006409. Compound B. Same compound as in Example 1. Compound C. A compound having the formula (E0) x H (E0) w H (E0) y H C 18 -alkyl-N-C 3 H 6 N-C 3 H 6 N (EO) 2 H where EO is ethyleneoxy and the sum of x, y, z and w is 10. Compound 1. Same compound as in Example 1. Compound 2. Same compound as Compound 1 but the number of oxyethylene units was 6 per mole tetraamine. The tests performed and the results obtained are shown in Table 3 below. Table 3. It is evident that the spin bath additives in accordance with the present invention have an improved ability to disperse solid and colloidal particles and to prevent the precipitation thereof in comparison with the spin bath additive disclosed in the Japanese Patent No. 48006409 and Japanese Patent Application No. 54101916.

Claims: C L A I M S 1. Use of an alkoxylated polyamine surfactant having the general formula RNAfC n H 2n NA 7 - x . 1 A (I) where R represents a hydrogen or an alifatic group with 1-24 carbon atoms, each A represents hydrogen, an alifatic group with 1-24 carbon atoms or an H (OC m H 2m ) y -group , where m is a number from 2-3, y is a number from 1 to 5, n is a number from 2-3, x is 4-8, with the proviso that the number of H(OC π .H 2ιr .) y -groups are from 1 to x+1, and the total number of carbon atoms in the aliphatic groups is from 8 to 45, as a viscose spin bath additive. 2. Use according to claim 1, wherein the bath contains from 5 to 15% by weight of H 2 S0 4 , from 15 to 30% by weight of Na 2 S0 4 and from 0 to 7% by weight of ZnS0 4 . 3. Use according to claim 1 or 2 wherein the alkoxylated polyamine surfactant is present in an amount of from 0.5 to 5000 ppm in the spin bath. 4. Use according to claim 1, 2 or 3 wherein the alkoxylated polyamine surfactant has the formula where R and x have the meaning mentioned in formula I , and A is a hydrogen or the group (C 2 H 4 0) γ H, where y is a number from 1-5, and the total number of C 2 H 4 0-units is from 4 to 15. 5. Use according to claim 1, 2, 3 or 4, wherein the alkoxylated polyamine surfactant is added as a dispersant and precipitation reducing additive. 6. Use according to claim 5 of the alkoxylated polyamine surfactant to reducing the clogging of nozzles and slits in the process of making viscose filamentary and film material. 7. A process for regeneration of cellulose from a viscose solution in a spin bath characterized in that the viscose solution is brought in contact with a spin bath containing from 0.5 to 5000 ppm of an alkoxylated polyamine surfactant having the formula I defined in claim 1. 8. A process according to claim 7 characterized in that the spin bath solution contains from 5 to 15% by weight of H 2 S0 4 , from 15 to 30% by weight of Na 2 S0 4 and from 0-7% by weight of ZnS0 4 . 9. A process according to claim 7 or 8 , characterized in that the alkoxylated polyamine surfactant has the formula RNAf C aHβNA .-.A (II) where R and x have the meaning mentioned in formula I , and A is a hydrogen or the group (C 2 H 4 0) y H, where y is a number from 1-5, and the total number of C 2 H 4 0-units is from 4 to 15.

Inventors: BJUR KENT, CASSEL ANDERS, STRANDBERG MARGRETH, UNEBACK INGEMAR, BJUR, KENT, CASSEL, ANDERS, STRANDBERG, MARGRETH, UNEBACK, INGEMAR
Applicants: AKZO NOBEL NV, BJUR KENT, CASSEL ANDERS, STRANDBERG MARGRETH, UNEBACK INGEMAR, AKZO NOBEL N.V., BJUR, KENT, CASSEL, ANDERS, STRANDBERG, MARGRETH, UNEBACK, INGEMAR
Application year: 1998
Main classification: D01F2
IPC codes: D01F2