SK282192A3 - Method of manufacture of modificating viscosity threads with raised sorption of water - Google Patents

Abstract

To viscose in the form of an alkaline solution of xanthan cellulose is added directly before spinning alkaline cellulose carbamate solution containing up to 15 wt. % polymeric carbamate with an average polymerization 100 to 900, nitrogen content 0.5 to 4.5 wt. % and a solution plump factor above 10, wherein the carbamate content of the spinning solution is maintained to 1 to 99 wt. %. The solution is then spun into a coagulation bath containing an aqueous acid solution sulfur and subsequently the fibers are softened in aqueous sulfuric acid solution at a temperature of 60 to 80 ° C at elongation in the range of 40 to 70%.

Description

The invention relates to a process for the production of modified viscose fibers with increased water sorption, improved affinity for pharmaceuticals, and improved physico-mechanical properties, while limiting emissions of carbon disulphide and hydrosulfide.

Viscose fibers with increased water sorption and dye affinity, with a fairly large ripple and wave-like feel are well known. Methods for producing such fibers are also known, the methods of which are based on incorporating either protein or its derivatives (modifiers) and polyglutamates into the viscose. Increased water sorption and dye affinity are also achieved by adding nitrogen-containing polyoxoalkynes or organic compounds such as acrylonitrile to ethylene oxide and formaldehyde to the viscose. These modifications are described in the monograph by A. Borynic, T.Skwarski; Wlókien sztusznych Technology (Artificial Fiber Technology), Naukowo-Techniszne Publishing Company 1970, and Japanese Patent Nos. 9052,62, 9054,62, 15250,63 and in the Australian Patent no. 237 464.

In German patent no. No. 2,636,654 discloses a process for producing cellulosic fibers with improved water sorption, wherein 5-20 wt.% Are added to the viscose. 7. water-soluble sodium carboxymethylcellulose, followed by spinning and finishing of the fibers, optionally bonding together.

German Patent Nos. 2,324,569 and 2,634,994 disclose a process for producing cellulosic fibers in which an acrylic polymer is added to the viscose by adding 2 to 30% by weight of the viscose. 7. a copolymer of acrylic and methacrylic acid, or alkali metal salts of polyacrylic acid. Cellulose regeneration fibers containing alkali metal alginates are known from U.S. Pat. 4,003,559.

Polish patent application P 267 647 relates to a manufacturing process in which viscose fibers with improved properties are obtained. Hydrolyzed polyacrylonitryl is added to the viscose, wherein the ratio of amide to carboxyl group content is in the range of 0 to 1. The modified fibers are spun in a spinning bath containing inorganic or organic chaining compounds and finally treated with an alkali metal hydroxide or chaining with agents such as calcium chloride, magnesium sulfate, epichlorohydrin, or formaldehyde. Known viscous fibers with improved water sorption, which are obtained by known manufacturing processes, usually have poorer physical-mechanical properties compared to standard fibers. In addition, they require the known manufacturing processes for obtaining modified viscose fibers by using additives which adversely affect the spinning process and the degree of viscose maturation, viscosity, spinnability and filterability.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are eliminated by a process for the production of modified viscose fibers with increased water sorption by the process according to the invention, which consists in adding to the viscose in the form of an alkyl solution of cellulose xanthate at a concentration of 6 to 12 wt. X-cellulose, preferably, by stirring or injecting, directly before spinning an alkaline solution of cellulose carbamate containing up to 15 wt. %, Preferably. 6 to 10 masses. X, a polymeric carbamate having an average polymerization degree of 100 to 100

900, a nitrogen content of 0.5 carblogging of the carbamate in the polymer mixture of up to 4.5 wt. Z and a solution factor above 10, while maintaining the spinning solution content at 1-99% by weight, the spinning solution being spun into fibers in a coagulation bath containing 10 to 200 g / l aqueous sulfuric acid with optional addition of sodium sulfate and thereafter the fibers are optionally softened in an aqueous solution of sulfuric acid at a concentration of 10 to 20 g / l at a temperature of 60 to 90 ° C, preferably at 50 ° C, with an extension in the range of 40 to 70 Z.

The fibers obtained by the process of the present invention consist of a mixture of regenerated cellulose and cellulose carbamate and exhibit a much greater moisture sorption compared to normal viscose fibers. Their sorption properties depend on the amount of cellulose carbamate contained and the conditions for their formation. The high-swelling cellulose carbamate, which is introduced into the structure of viscous fibers, alters the capillary array of fibers made from the polymer blend and increases swelling considerably.

Fibers produced by the process of the invention also have improved affinity for dyes and have greater immunity to bacteria than viscose fibers. The good solubility of both cellulose carbamate and cellulose xanthate in suitable bases makes it possible according to the invention to prepare spinning solutions from a mixture of both cellulose derivatives.

The spinning time of such a mixture in an acid spinning bath decomposes the cellulose xynthate into cellulose, while the cellulose carbamate contained in the spin bath either coagulates or its degree of substitution slightly decreases.

An advantage of the process of the present invention is to melt fibers with a wide range of cellulose carbamate content

-4% range. This allows the unconstrained miscibility of the viscose with the cellulose carbamate solution.

The process according to the invention makes it possible to substantially reduce the emissions of carbon disulphide and hydrosulphide, thereby contributing to environmental protection. The properties of cellulose, cellulose carbamate and recovered fibers are determined according to the following methods:

average polymerization degree of cellulose according to the method described in Das Papier no. 12. p. 187, 1,958

nitrogen content in the cellulose carbamate and the fibers obtained by the method of Kiejdahl described in Chemistry Analityczna No.5, pp. 1019, 1960

-clogging coefficient according to BN-70 / 7616-03

water retention value (WRV) according to the method described in Cellulose Chemistry and Technology vol.14, p.893,1980.

The swelling index (SP) is determined as WRV at a spin speed of 1000 rpm for 90 seconds.

The present invention is further illustrated by the following examples of specific embodiments thereof, without being limited thereto.

Examples

Examples 1 to 3

To 100 parts by weight of viscose, which contains 8.8% by weight of cellulose and 6.4% by weight of sodium hydroxide and has a viscosity of 45 seconds, is added in Table 1 the amount of aqueous alkaline solution of cellulose carbamate with stirring. The cellulose carbamate added has an average polymerization degree of DP = 330 and a nitrogen content of 2.9.7. The cellulose carbamate solution contains 7.65.7.

% by weight of cellulose carbamate; and 8.7% by weight of sodium hydroxide and has a viscosity of 58 sec. and a wettability factor of Kw-38.5. The resulting mixture is further filtered and vented at 0-5 ° C. The spinning solution thus prepared is spun in a coagulation bath at 40 ° C containing 120 g / l sulfuric acid and 280 g / l sodium sulfate. The obtained fibers are softened in a bath containing 10 g / l sulfuric acid at 80 °. The spinning speed is 30 m / min and the elongation at spinning is 40%. The finishing of these fibers is the same as the viscose process.

Table 1 below shows the properties of the modified viscose fibers obtained as a function of the amount of cellulose carbamate added as a modifying agent. A comparison with standard viscous fibers is also provided.

Table 1 Properties of modified viscose fibers

F 'r í - Loading zvlákňo- Sah bsah Mechanical properties WRV SF ' Contents k lad solution, within the body being fiber 7th 7th vlhko- c e 1 u 1 ó: for k a Ti HU- F'r e- vaccination sti vo fiber no. from xant- from carb- 7th tr žev- I 'd to vacia ha tu Amato d text NatOst not HU- cN / tex 7th durability cN / tex 100 _ 0, 00 2.00 19, 4 16 τ 7tr s- »7 / vJ 71 106 10.2 1 50 50 0.70 7.42 15.6 · _ »· -’ 8.36 129 180 14.5 'Ί * * " 20 80 0, 72 2.29 14.4 17 2, 85 134 167 15.2 1 99 1.10 2, 10 16.0 14 O 7 · ' 142 140 12, 1

Compared to the standard viscose fibers, the obtained modified fibers are characterized by a higher water retention value (WRV) and an increased swelling index (SF ·). These values> indicate also increased water absorption and dye sorption. In addition, the fibers have greater resistance to bacteria and fungi, especially under humid conditions.

Examples 4 to 6

To 100 parts by weight viscose, which contains 6.77% by weight cellulose and 3.7% by weight sodium hydroxide and has a viscosity

The amount of alkaline cellulose carbamate solution shown in Table 2 is sprayed immediately before spinning.

The cellulose carbamate has an average polymerization degree of DP = 270 and a nitrogen content of 1.5% by weight. The cellulose carbamate solution contains 6.68% by weight cellulose carbamate and 8.7% by weight sodium hydroxide and has a viscosity of 33 sec and a wadability factor Kw = 165. The spinning solution obtained is spun in a spinning bath at 40 ° C containing 10 g / l sulfuric acid. Then the obtained fibers are passed through a softening bath at 70 ° C containing 10 g / l sulfuric acid. In the latter process, 40 7 elongations are used and the winding speed is 30 m / min.

Table 2 shows the properties of the obtained modified viscose fibers of the added cellulose carbamate.

depending on quantity

7-

Table 2

Properties of modified viscose fibers

Example - Z 1ženie ie zvlákňo- Contents Mec har n i c k é ✓1astnosti WRO SP Contents ice solution, within the body being fiber vlhko- cellulose k a Ti HU- vaccination sti vo For- fiber no. from xant- from carb- 7th tr žev- d ¾ e vac ia ha tu Amato d text NatOst not HU- 7th cN / tex 7th ževna- weight the cN / tex 4 99 s 0.24 1.72 17.2 and 6.25 1 '2) 260 12, 0 b SO 20 0, 78 1.54 17.9 13 6, 10 157 and 13.9 about 20 80 0.97 2.62 12.5 26 6.01 158 172 14.2

Compared to standard viscose fibers, the modified fibers obtained exhibit increased water uptake and dye affinity and have better resistance to bacteria and fungi, especially under humid conditions.

. The modified water-absorbent viscose fibers produced by the process of the present invention are mainly used in medicine, in sanitary dressing materials, the textile industry and in technology such as absorbent material.

Claims (1)

A process for producing modified viscose fibers with increased water sorption, characterized in that an alkaline solution is preferably introduced into the viscose in the form of an alkaline solution of xanthan cellulose at a concentration of 0 to 12% by weight of cellulose, by stirring or injecting directly before spinning. cellulose carbamate containing up to 15% by weight Z, preferably 6 to 10% by weight X, of a polymeric carbamate having an average polymerization degree of 100 to 900, a nitrogen content of 0.5 to 4.5% by weight, and a solution wasting factor above 10, The polymeric blend solution is maintained at 1 to 99% by weight, while the spinning solution is spun into fibers in a coagulation bath containing 10 to 200 g / l aqueous sulfuric acid with optional addition of sodium sulfate, and then optionally fibers are spun in aqueous sulfuric acid solution. concentration 10 up to 20 g / l at a temperature of 60 to 90 ° C, preferably 80 ° C, with an extension in the range of 40 to 70 ° C.