A high-strength environmentally friendly adsorption fiber and its preparation method and application

Abstract

The present invention belongs to the technical field of functional fiber preparation and discloses a high-strength, environmentally friendly adsorbent fiber, its preparation method, and application. The high-strength, environmentally friendly adsorbent fiber is made from biodegradable polylactic acid and thermoplastic cellulose diacetate. Its sheath is thermoplastic cellulose diacetate and its core is polylactic acid. The fiber can be used to adsorb chemical components. The environmentally friendly sheath-core adsorbent fiber prepared by the present invention has excellent adsorption function and good strength. It does not produce any environmentally harmful substances during production and use. The raw materials are biodegradable, environmentally friendly, and the manufacturing process is simple.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional fiber preparation, and in particular relates to a high-strength environmentally friendly adsorption fiber and a preparation method and application thereof. Background Art

[0002] With the continuous development and advancement of science and technology, more and more adsorbent fibers have been developed. However, the overuse of non-degradable materials can cause environmental pollution and overuse of non-renewable resources, necessitating the introduction of degradable materials. To ensure adequate adsorption, adsorbent fibers with high surface areas and excellent adsorption properties have been developed through technological research. Therefore, the selection of degradable polymers as raw materials and advanced preparation technologies to produce environmentally friendly adsorbent materials are of great significance.

[0003] Polylactic acid (PLA) is a renewable plant-derived polymer that is fully biodegradable, non-toxic, and environmentally friendly, and possesses a certain degree of adsorption capacity. Cellulose diacetate (CDA) is derived from a widely available natural material and has a porous surface that facilitates the adsorption of chemical components. Therefore, the use of PLA and CDA to prepare environmentally friendly, skin-core adsorption fibers has broad application prospects.

[0004] At present, the main preparation methods of adsorption fibers include activation process, electrostatic spinning and so on. In patent CN115074860A, macroporous carbon fiber is used as the skin layer, and non-porous carbon fiber is used as the core layer. The material is heated to 800-1100°C and then steam is introduced for activation for a period of time to prepare a porous carbon fiber adsorption material. However, the activation process has the problem of long production process time and low strength of the prepared fiber. Patent CN102691136A uses coaxial electrostatic spinning technology to blend polyacrylonitrile and other polymers as the skin layer, and other polymers are used for the core layer to prepare porous coaxial adsorption fiber materials. The preparation process of this method is relatively complicated, and the materials used are not completely biodegradable, which is not environmentally friendly.

[0005] Since CDA has poor thermoplasticity and cannot be melt-processed, CDA and PLA cannot be melt-spun to produce sheath-core fibers. In order to prepare sheath-core adsorption fibers, CDA must be plasticized and modified to improve its thermal processing properties. Summary of the Invention

[0006] In view of this, the present invention provides a high-strength environmentally friendly adsorption fiber and its preparation method and application. The adsorption fiber prepared by this method has a high specific surface area and good adsorption performance. In addition, the preparation process is simple and the cost is low, which is conducive to industrialization.

[0007] To achieve the above object, the present invention is implemented through the following technical solutions:

[0008] A method for preparing high-strength environmentally friendly adsorption fiber includes the following preparation steps:

[0009] S1. Using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers, cellulose diacetate was plasticized and modified to obtain thermoplastic cellulose diacetate;

[0010] S2. Thermoplastic cellulose diacetate and polylactic acid were added to a twin-screw extruder in a mass ratio of 1:9-1:1, melt-stirred for 5-15 minutes at a temperature range of 220-260 ° C, and melt-extruded through a core-sheath composite spinning assembly at 230-260 ° C, and ejected from the core-sheath composite spinneret to obtain a raw yarn;

[0011] S3. The raw silk is stretched 1-5 times to obtain high-strength environmentally friendly adsorption fiber.

[0012] Furthermore, in the above preparation method, the melting point of the polylactic acid is 210-230°C.

[0013] Furthermore, in the above preparation method, the melting point of the thermoplastic cellulose diacetate is 200°C.

[0014] Furthermore, in the above preparation method, the temperature range of the stretching is 100-130°C.

[0015] The present invention also provides a high-strength environmentally friendly adsorption fiber, which has a skin-core structure. The skin material of the adsorption fiber is thermoplastic cellulose diacetate, the core material of the adsorption fiber is polylactic acid, and the single fiber diameter of the adsorption fiber is 5.3-28.3 dtex.

[0016] Furthermore, the surface pore size of the adsorption fiber is 86-452nm, and the specific surface area is 1057-1616m 2 / g.

[0017] Furthermore, the single fiber tensile strength of the adsorption fiber is 1.51-3.43 cN / dtex.

[0018] The present invention also provides a high-strength environmentally friendly adsorbent fiber prepared by the above-mentioned preparation method or the use of the above-mentioned high-strength environmentally friendly adsorbent fiber in processing woven fabrics, knitted fabrics or non-woven fabrics.

[0019] Compared with the existing technology, the present invention first modifies CDA, uses the modified CDA as the skin layer and PLA as the core layer, and melt-spins to prepare adsorption fibers with a porous surface structure. By increasing the specific surface area and porosity of the fiber, the adsorption performance of the fiber is improved, and at the same time, the fiber has good tensile strength. The manufacturing process is simple and the cost is low. It can be well applied in the field of environmentally friendly functional materials to meet the production needs of functional fibers. DETAILED DESCRIPTION

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] raw material:

[0022] PLA was purchased from Natureworks, USA, brand 6202D.

[0023] CDA was purchased from Sichuan Pushi Cellulose Acetate Co., Ltd., model LVI.

[0024] Example 1

[0025] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0026] (2) Weigh the corresponding mass of PLA particles (melting point 210°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 9 / 1.

[0027] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 220° C. for 15 min, and after melt extrusion, passed through a core-sheath composite spinning assembly at 230° C. and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0028] (4) The raw silk obtained in step (3) was stretched at 100° C. with a stretching ratio of 5 times.

[0029] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 5.3 dtex, a surface pore size of 328-452 nm, and a specific surface area of ​​1057 m 2 / g, and the tensile strength is 3.43cN / dtex.

[0030] Example 2

[0031] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0032] (2) Weigh the corresponding mass of PLA particles (melting point 210°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 8 / 2.

[0033] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 230°C for 10 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 240°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0034] (4) The raw silk obtained in step (3) is stretched at 110° C. with a stretching ratio of 1.

[0035] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 25.9 dtex, a surface pore size of 276-336 nm, and a specific surface area of ​​1173 m 2 / g, and the tensile strength is 2.23cN / dtex.

[0036] Example 3

[0037] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0038] (2) Weigh the corresponding mass of PLA particles (melting point 220°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 7 / 3.

[0039] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 240°C for 5 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 250°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0040] (4) The raw silk obtained in step (3) is stretched at 120° C. with a stretching ratio of 3 times.

[0041] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 16.4 dtex, a surface pore size of 208-316 nm, and a specific surface area of ​​1234 m 2 / g, and the tensile strength is 1.97cN / dtex.

[0042] Example 4

[0043] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0044] (2) Weigh the corresponding mass of PLA particles (melting point 230°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 6 / 4.

[0045] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 250°C for 5 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 260°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0046] (4) The raw silk obtained in step (3) is stretched at 120° C. with a stretching ratio of 4 times.

[0047] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 9.2dtex, a surface pore size of 98-219nm, and a specific surface area of ​​1539m 2 / g, and the tensile strength is 1.63cN / dtex.

[0048] Example 5

[0049] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0050] (2) Weigh the corresponding mass of PLA particles (melting point 230°C) and thermoplastic CDA, with the mass ratio of PLA to thermoplastic CDA being 1 / 1.

[0051] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 260°C for 5 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 260°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0052] (4) The raw silk obtained in step (3) is stretched at 120° C. with a stretching ratio of 4 times.

[0053] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 28.3 dtex, a surface pore size of 86-258 nm, and a specific surface area of ​​1516 m 2 / g, and the tensile strength is 1.51cN / dtex.

[0054] Example 6

[0055] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0056] (2) Weigh the corresponding mass of PLA particles (melting point 220°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 8 / 2.

[0057] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 230°C for 5 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 240°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0058] (4) The raw silk obtained in step (3) is stretched at 120° C. with a stretching ratio of 4 times.

[0059] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 9.7 dtex, a surface pore size of 95-203 nm, and a specific surface area of ​​1382 m 2 / g, and the tensile strength is 2.24cN / dtex.

[0060] Example 7

[0061] (1) CDA was plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA with a melting point of 200°C.

[0062] (2) Weigh the corresponding mass of PLA particles (melting point 210°C) and thermoplastic CDA. The mass ratio of PLA to thermoplastic CDA is 7 / 3.

[0063] (3) The PLA and thermoplastic CDA weighed in step (2) were added to a twin-screw extruder respectively, stirred at 230°C for 5 minutes, and after melt extrusion, passed through a core-sheath composite spinning assembly at 240°C, and then ejected through a core-sheath composite spinneret to obtain a raw yarn.

[0064] (4) The raw silk obtained in step (3) is stretched at 120° C. with a stretching ratio of 4 times.

[0065] The obtained environmentally friendly skin-core structure adsorption fiber has an average diameter of 10.3 dtex, a surface pore size of 96-249 nm, and a specific surface area of ​​1443 m 2 / g, and the tensile strength is 2.13cN / dtex.

[0066] Comparative Example 1

[0067] (1) PLA (melting point 210°C) was weighed and added to a twin-screw extruder. After stirring at 230°C for 5 min, it was passed through a core-sheath composite spinning assembly at 240°C and then ejected through a core-sheath composite spinneret to obtain a precursor. The precursor was drawn at 120°C with a draw ratio of 4. The resulting PLA fiber had a diameter of 8.6 dtex, a tensile strength of 3.56 cN / dtex, and no voids on the fiber surface.

[0068] Comparative Example 2

[0069] (1) First, CDA was plasticized and modified with epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic CDA (melting point 200°C). Thermoplastic CDA was weighed and added to a twin-screw extruder. After stirring at 230°C for 5 minutes, it passed through a 240°C same-plate sheath-core composite spinning assembly and then ejected through a sheath-core composite spinneret to obtain a precursor. The precursor was stretched at 120°C with a stretching multiple of 2 times. The diameter of the obtained environmentally friendly sheath-core structure adsorption fiber was 22.9 dtex, the surface pore size was 88-260nm, and the specific surface area was 1638m 2 / g, and the tensile strength is 0.46cN / dtex.

Claims

1. A method for preparing high-strength environmentally friendly adsorption fiber, characterized in that: The method comprises the following preparation steps: S1. cellulose diacetate is plasticized and modified using epoxy soybean oil and polyhydroxyalkanoate oligomers as plasticizers to obtain thermoplastic cellulose diacetate having a melting point of 200°C. S2. Thermoplastic cellulose diacetate and polylactic acid were added to a twin-screw extruder in a mass ratio of 1:9-1:1, melt-stirred at a temperature range of 220-260°C for 5-15 min, and then melt-extruded through a core-sheath composite spinning assembly at 230-260°C to produce a precursor yarn. The melting point of the polylactic acid was 210-230°C. S3. The raw silk is drawn 1-5 times to obtain a high-strength environmentally friendly adsorbent fiber; The adsorption fiber is of a skin-core structure, the skin layer material of the adsorption fiber is thermoplastic cellulose diacetate, and the core layer material of the adsorption fiber is polylactic acid.

2. The preparation method according to claim 1, characterized in that The temperature range of the drawing is 100-130°C.

3. A high-strength environmentally friendly adsorption fiber, characterized in that: The high-strength environmentally friendly adsorption fiber is prepared by the preparation method according to claim 1 or 2, and the single fiber diameter of the adsorption fiber is 5.3-28.3 dtex.

4. The high-strength environmentally friendly adsorbent fiber according to claim 3, characterized in that: The surface pore size of the adsorption fiber is 86-452 nm, and the specific surface area is 1057-1616 m2 / g.

5. The high-strength environmentally friendly adsorbent fiber according to claim 3, characterized in that: The single fiber tensile strength of the adsorption fiber is 1.51-3.43 cN / dtex.

6. Use of the high-strength environmentally friendly adsorbent fiber according to any one of claims 3 to 5 in processing woven fabrics, knitted fabrics or non-woven fabrics.