Production method of extinction Lyocell fiber

Abstract

The invention discloses a production method of extinction Lyocell fibers, and belongs to the technical field of preparation of Lyocell fibers and the field of biodegradable materials. The method comprises the following steps: step SS1: adding anatase titanium dioxide into an NMMO (N-methylmorpholine-N-oxide) aqueous solution, and stirring on a magnetic stirrer to obtain a solution 1; step SS2, mixing the solution 1 with pulp to obtain a mixed system 1; and step SS3, concentrating the mixed system 1 until the mass fraction of the NMMO is 86-88% to obtain a spinning solution, and then spinning, washing, cutting, washing, oiling and drying to obtain the extinction Lyocell fiber. By reasonably adding the dosage of titanium dioxide and optimizing the process, the rheological behavior of the spinning solution is improved, the key problem of poor dispersion stability of titanium dioxide in a glue solution is solved, and the available range of the lyocell fiber is widened.

Description

Technical Field

[0001] The invention relates to a production method of matt Lyocell fiber, belonging to the technical field of Lyocell fiber preparation and the field of biodegradable materials. Background Art

[0002] The Lyocell fiber production technology has gradually matured, and the research on differentiated products has gradually deepened. For matte-type products, companies such as Lenzing have already produced related products, indicating that the market prospects for matte Lyocell fibers are still relatively broad.

[0003] The comparative document 1 has a public application number of 202211164737.8 and is an invention patent entitled "A matting lyocell fiber and a production method thereof". It solves the problem of how to add a matting agent during the production process of lyocell fiber to improve its optical properties while avoiding the problem of system compatibility problems and decreased mechanical properties caused by the addition.

[0004] The comparative document 2 has a public application number of 202280066000.4 and is an invention patent application entitled "Lyocell fiber containing matting agent and its use in the production of textile fabrics". It solves the technical problem of how to effectively reduce the gloss of lyocell fiber without increasing wear while retaining its mechanical strength and other properties, such as feel and softness.

[0005] Comparative document 3, with public application number 202311115810.7 and titled “Method for preparing EG-TiO 2, EG-TiO 2-NMMO dispersion and fully matt Lyocell fiber”, solves the problem of how to effectively add matting agent in the production process of lyocell fiber to improve the gloss effect of the fiber surface, while avoiding the problem of spinneret hole clogging caused by poor dispersion of rutile titanium dioxide in NMMO. Summary of the invention

[0006] The purpose of the present invention is to overcome the technical defects of the prior art, solve the above-mentioned technical problems, propose a method for producing matte Lyocell fiber, produce Lyocell fiber with matte performance, solve the key problem of poor dispersion stability of titanium dioxide in the glue solution, broaden the available scope of Lyocell fiber, and downstream enterprises can use the fiber to develop and produce matte products, thereby increasing the category of Lyocell fiber products on the market.

[0007] The present invention specifically adopts the following technical solution: a method for producing matt Lyocell fiber, comprising the following steps:

[0008] Step SS1: adding anatase titanium dioxide to an NMMO aqueous solution and stirring on a magnetic stirrer to obtain a solution 1;

[0009] Step SS2: mixing solution 1 with pulp to obtain a mixed system 1;

[0010] Step SS3: Concentrate the mixed system 1 to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and then perform spinning, water washing, cutting, water washing, oiling, and drying to obtain the matte Lyocell fiber.

[0011] As a preferred embodiment, the step SS1 specifically comprises: adding anatase titanium dioxide with a particle size of 100 to 300 nm to a 50 to 65% by mass NMMO aqueous solution, and stirring the solution on a magnetic stirrer at 1000 r / min for 30 minutes to obtain a solution 1.

[0012] As a preferred embodiment, the step SS2 specifically comprises: mixing the solution 1 with the pulp, stirring for 30 to 60 minutes at 80 to 90° C., to obtain a mixed system 1.

[0013] As a preferred embodiment, the step SS3 specifically includes: concentrating the mixed system 1 at 100-120°C to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and then spinning, washing, cutting, washing, oiling, and drying to obtain the matte Lyocell fiber.

[0014] As a preferred embodiment, the cellulose content of the pulp in the spinning solution in step SS3 is 11-12 wt%.

[0015] As a preferred embodiment, the step SS3 also includes: conveying the slurry to the screw by pressurization, then to the metering pump, and then to the spinneret for spraying out, and then winding, bundling and stretching the filaments after passing through a coagulation bath, using three-pass stretching during the stretching process, and finally cutting the fiber bundle.

[0016] As a preferred embodiment, the conditions of the coagulation bath are: mass concentration 20%, temperature 20°C.

[0017] As a preferred embodiment, the stretching temperature of the stretching process is 30-35°C, and the stretching multiple is 2-3.

[0018] As a preferred embodiment, the fiber bundle is cut at a knife speed of 40 m / min and a length of 33 mm.

[0019] As a preferred embodiment, the linear density of the matt Lyocell fiber is 1.0-2.5 dtex, and the dry breaking strength is higher than 3.2 cN / dtex, referring to the industry standard FZ / T 52019-2018.

[0020] The beneficial effects achieved by the present invention are as follows: the present invention proposes a method for preparing matt Lyocell fiber, firstly, a dispersion test screening is carried out on anatase titanium dioxide of different specifications, and then a suitable particle size is selected for matt Lyocell fiber production, the fiber linear density is 1.0-2.5 dtex, and the dry breaking strength is higher than 3.2 cN / dtex; at the same time, the present invention improves the rheological behavior of the spinning solution by reasonably adding titanium dioxide dosage and optimizing the process, solves the key problem of poor dispersion stability of titanium dioxide in the colloid solution, broadens the available scope of Lyocell fiber, and realizes the low-carbon, environmentally friendly and sustainable development and utilization function of Lyocell fiber. DETAILED DESCRIPTION

[0021] The present invention is further described below. The following examples are only used to more clearly illustrate the technical solution of the present invention, and are not intended to limit the protection scope of the present invention.

[0022] Embodiment 1: The present invention provides a method for producing a matte Lyocell fiber, comprising the following steps:

[0023] Step SS1: adding anatase titanium dioxide with a particle size of 100 to 300 nm to a 50% by mass NMMO aqueous solution, and stirring the solution on a magnetic stirrer at 1000 r / min for 30 min to obtain a solution 1;

[0024] Step SS2: stirring at 80-90° C. for 30-60 min to obtain a mixed system 1;

[0025] Step SS3: The mixed system 1 is concentrated at 100-120°C to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and the spinning solution is conveyed to the screw by pressurization, and then to the metering pump, and then to the spinneret for spraying, and the filaments are wound, bundled, and drawn after passing through a coagulation bath, and three-pass drawing is adopted in the drawing process, and finally the fiber bundle is cut to obtain the matte Lyocell fiber; the pulp cellulose content in the spinning solution in step SS3 is 11-12wt%; the conditions of the coagulation bath are: mass concentration 20%, temperature 20°C; the drawing temperature of the drawing process is 30-35°C, and the drawing multiple is 2-3; the knife speed of the fiber bundle cutting is 40m / min, and the length is 33mm. The obtained matte Lyocell fiber has a linear density of 1.0-2.5dtex, and a dry breaking strength higher than 3.2cN / dtex.

[0026] Embodiment 2: The present invention provides a method for producing a matte Lyocell fiber, comprising the following steps:

[0027] Step SS1: adding anatase titanium dioxide with a particle size of 100 to 300 nm to a 55% by mass NMMO aqueous solution, and stirring the solution on a magnetic stirrer at 1000 r / min for 30 min to obtain a solution 1;

[0028] Step SS2: stirring at 80-90° C. for 30-60 min to obtain a mixed system 1;

[0029] Step SS3: The mixed system 1 is concentrated at 100-120°C to a mass fraction of NMMO of 86-88%, and a spinning solution is obtained. The spinning solution is conveyed to the screw by supercharging, and then to the metering pump, and then to the spinneret for spraying. After passing through the coagulation bath, the filaments are wound, bundled, and drawn. Three-pass drawing is used in the drawing process, and finally the fiber bundle is cut to obtain the matte Lyocell fiber; the slurry cellulose content in the spinning solution in step SS3 is 11-12wt%; the conditions of the coagulation bath are: mass concentration 20%, temperature 20°C; the drawing temperature of the drawing process is 30-35°C, and the drawing multiple is 2-3; the knife speed of the fiber bundle is 40m / min, and the length is 33mm. The obtained matte Lyocell fiber has a linear density of 1.0-2.5dtex, and a dry breaking strength higher than 3.2cN / dtex, referring to the industry standard FZ / T 52019-2018.

[0030] Embodiment 3: The present invention provides a method for producing matte Lyocell fiber, comprising the following steps:

[0031] Step SS1: adding anatase titanium dioxide with a particle size of 100 to 300 nm to a 60% by mass NMMO aqueous solution, and stirring the solution on a magnetic stirrer at 1000 r / min for 30 min to obtain a solution 1;

[0032] Step SS2: stirring at 80-90° C. for 30-60 min to obtain a mixed system 1;

[0033] Step SS3: The mixed system 1 is concentrated at 100-120°C to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and the spinning solution is conveyed to the screw by pressurization, and then to the metering pump, and then to the spinneret for spraying, and the filaments are wound, bundled, and drawn after passing through a coagulation bath, and three-pass drawing is adopted in the drawing process, and finally the fiber bundle is cut to obtain the matte Lyocell fiber; the pulp cellulose content in the spinning solution in step SS3 is 11-12wt%; the conditions of the coagulation bath are: mass concentration 20%, temperature 20°C; the drawing temperature of the drawing process is 30-35°C, and the drawing multiple is 2-3; the knife speed of the fiber bundle cutting is 40m / min, and the length is 33mm. The obtained matte Lyocell fiber has a linear density of 1.0-2.5dtex, and a dry breaking strength higher than 3.2cN / dtex.

[0034] The present invention provides a method for preparing matt Lyocell fiber. Firstly, a dispersibility test is performed on anatase titanium dioxide of different specifications, and then a suitable particle size is selected for matt Lyocell fiber production. The fiber linear density is between 1.0 and 2.5 dtex, and the dry breaking strength is higher than 3.2 cN / dtex. At the same time, the present invention improves the rheological behavior of the spinning solution by reasonably adding titanium dioxide dosage and optimizing the process, solves the key problem of poor dispersion stability of titanium dioxide in the glue solution, broadens the available scope of Lyocell fiber, and realizes the low-carbon, environmentally friendly and sustainable development and utilization function of Lyocell fiber.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for producing matte Lyocell fiber, characterized in that: The steps include: Step SS1: adding anatase titanium dioxide to an NMMO aqueous solution and stirring on a magnetic stirrer to obtain a solution 1; Step SS2: mixing solution 1 with pulp to obtain a mixed system 1; Step SS3: Concentrate the mixed system 1 to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and then perform spinning, water washing, cutting, water washing, oiling, and drying to obtain the matte Lyocell fiber.

2. The method for producing a matte Lyocell fiber according to claim 1, characterized in that: The step SS1 specifically includes: adding anatase titanium dioxide with a particle size of 100 to 300 nm into a 50 to 65% NMMO aqueous solution by mass, and stirring the solution on a magnetic stirrer at 1000 r / min for 30 minutes to obtain a solution 1.

3. The method for producing a matte Lyocell fiber according to claim 1, characterized in that: The step SS2 specifically includes: mixing the solution 1 with the pulp, stirring at 80 to 90° C. for 30 to 60 minutes, to obtain a mixed system 1.

4. The method for producing a matte Lyocell fiber according to claim 1, characterized in that: The step SS3 specifically includes: concentrating the mixed system 1 at 100-120° C. to a mass fraction of NMMO of 86-88% to obtain a spinning solution, and then spinning, washing, cutting, washing, oiling, and drying to obtain the matte Lyocell fiber.

5. The method for producing a matte Lyocell fiber according to claim 4, characterized in that: The cellulose content of the pulp in the spinning solution in step SS3 is 11-12 wt%.

6. The method for producing a matte Lyocell fiber according to claim 4, characterized in that: The step SS3 also includes: conveying the slurry to the screw by pressurization, then to the metering pump, and then to the spinneret for spraying, and then winding, bundling and stretching the filaments through a coagulation bath, using three-pass stretching during the stretching process, and finally cutting the fiber bundle.

7. The method for producing a matte Lyocell fiber according to claim 6, characterized in that: The conditions of the coagulation bath are: mass concentration 20%, temperature 20°C.

8. The method for producing a matte Lyocell fiber according to claim 6, characterized in that: The stretching temperature of the stretching process is 30-35° C., and the stretching multiple is 2-3.

9. The method for producing a matte Lyocell fiber according to claim 6, characterized in that: The fiber bundle is cut at a knife speed of 40 m / min and a length of 33 mm.

10. The method for producing a matte Lyocell fiber according to claim 1, characterized in that: The linear density of the matt Lyocell fiber is 1.0-2.5 dtex, and the dry breaking strength is higher than 3.2 cN / dtex.