SU552374A1 - Method for producing high strength cellulose hydrate fibers - Google Patents

Description

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The invention relates to the field of the physical chemistry of high molecular weight compounds, more precisely the physical chemistry of cellulose, and can be used to produce high strength artificial fibers based on cellulose hydrate.

A known method of producing high strength cellulose hydrate fibers through cellulose xanthate 1. This method is associated with a very complex xaltogenation process and subsequent saponification of cellulose xanthates and entails environmental pollution. The strength of the hydrated cellulose volokol obtained by saponification of xanthates, usually does not exceed 40-50

A known method of producing high strength cellulose hydrate fortizan by spinning a diacetylcellulose dope into a precipitation bath followed by stretching while heating and saponification of the bases of the molded fiber. Fibers with a strength of up to 97 kg / mm 2 are obtained. This method requires large expenditures on equipment for forced stretching, is complex and multistage.

In order to obtain uniaxially oriented fibers, to simplify and speed up production processes, it is proposed to spin the diacetylcellulose spinning solution with a zero spinnerette into a water bath.

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at room temperature with the subsequent critical plasticization of the formed fiber and process it at 50-60 ° C with a 2-3% aqueous solution of phenol containing 0.1–3% sodium sulfate.

The proposed method consists of two stages.

1. Forming fiber from cellulose diacetate.

Cellulose diacetate from the Vladimirsky plant, obtained by partial saponification of triacetate, is used as a raw material. The bound acetic acid content is 56.5% (theoretical for diacetate). Fibers are molded from 10-20% solutions of cellulose diacetate in acetone. Water is used as a precipitation bath. The forming temperature is 10-30 ° C. The stringer is stretched to zero. The fibers are drawn by 30-50% in a plasticizing bath containing 75% aqueous ztalol.

2. Preparation of the uniaxially oriented cellulose cellulose volokol from cellulose diacetate.

The fibers on the bobbins are placed in a bath of the following composition: phenol 2-3%, sodium sulfate 0.1-3%, water 94-96%. Processing temperature 50-60 ° C. Processing time 10-

20 minutes. In this case, the spontaneous elongation of the fiber reaches 90-120%.

Spontaneously elongated fibers are washed with alkali (for example, 1 g of NaOH per 1 g of fiber), in 70-75% aqueous ethanol at a fixed fiber length, washed with water until no reaction to alkali and dried at room temperature.

Thus obtained fibers have a strength of up to 99 kg / mm, a tensile elongation of 2-3%.

Example 1. Fiber is formed from a 15% solution of diacetylcellulose in acetone. Water is used as a precipitator. The temperature of the molding is room. The stringer is stretched to zero. The fibers are stretched by 50% in a plasticization bath containing 76% aqueous ethanol.

Then the fibers obtained on bobbins are placed in a bath of the following composition: phenol 3%, sodium sulfate. 3%, the rest is water.

Processing temperature 60 ° C. Processing time 15 min. In this case, the spontaneous elongation of the fiber reaches 120%. Spontaneously elongated fibers are washed with alkali (1 g of NaOH per 1 g of fiber) in 75% aqueous ethanol at a fixed fiber length, washed with water until no reaction to alkali, and exist at room temperature.

Thus obtained fibers have a strength of 99 kg / mm elongation of 3%.

Example 2. A fiber was prepared as in Example 1. A bath contained 2% phenol, 2% sodium sulfate. Spontaneous elimination 110%.

The fibers obtained have a strength of 82 kg / mm.

Example 3. A fiber is prepared as in Example 1. A bath contains 2% phenol.

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0.1% sodium sulfate. Spontaneous elongation of 90% at 50 ° C. The fibers obtained have a strength of 50 kg / mm.

Thus, the proposed method has the following advantages over the well-known: the stretching process occurs spontaneously, i.e., spontaneously, without special stretching devices, at lower temperatures; energy costs are reduced, the process is simplified, simplified and cheaper.

Claims (3)

1. US patent No. 2356014, cl. 264-207, published. 1950. 2. Rogovin 3. A. Fundamentals of chemistry and technology of chemical fibers, M., ed. “Chemistry, vol. I, 1974, p. 501 (npoTOTHin).