阅读说明：本技术 一种少层二维材料改性纤维素纤维的方法 (Method for modifying cellulose fiber by using few-layer two-dimensional material ) 是由 周建 李久荣 丁古巧 于 2019-10-11 设计创作，主要内容包括：本发明涉及少层二维材料改性纤维素纤维的方法以及分散剂、纳米纤维素和少层二维材料在改性纤维素纤维中的用途。该方法包括步骤：将分散剂在碱存在下分散在水中以配置成碱性分散液,然后向其中加入纳米纤维素并分散乳化,最后将向其中加入层状二维材料,制得层状二维材料的水性分散液,对该水性分散液进行剪切分散；采用一种或多种机械方式处理剪切分散后的层状二维材料水性分散液以机械剥离层状材料从而获得少层二维材料的水性分散溶液；将少层二维材料的水性分散液与纤维素纤维的纺丝液进行混合,然后纺丝制备少层二维材料改性的纤维素纤维。该方法制得的纤维素纤维具有良好的干湿强度、断裂伸长率、耐光性和耐磨性。(The invention relates to a method for modifying cellulose fibers with a few-layer two-dimensional material, and to the use of a dispersant, nanocellulose and a few-layer two-dimensional material for modifying cellulose fibers. The method comprises the following steps: dispersing a dispersing agent in water in the presence of alkali to prepare an alkaline dispersion liquid, then adding nano-cellulose into the alkaline dispersion liquid, dispersing and emulsifying the nano-cellulose, finally adding a layered two-dimensional material into the alkaline dispersion liquid to prepare an aqueous dispersion liquid of the layered two-dimensional material, and shearing and dispersing the aqueous dispersion liquid; treating the sheared and dispersed layered two-dimensional material aqueous dispersion liquid by adopting one or more mechanical modes to mechanically peel the layered material so as to obtain an aqueous dispersion solution of the few-layer two-dimensional material; and mixing the aqueous dispersion liquid of the few-layer two-dimensional material with the spinning solution of the cellulose fiber, and then spinning to prepare the few-layer two-dimensional material modified cellulose fiber. The cellulose fiber prepared by the method has good dry wet strength, elongation at break, light resistance and wear resistance.)

1. A method of modifying cellulose fibers with a reduced ply of two-dimensional material, wherein the method comprises the steps of:

(1) dispersing a dispersing agent in water in the presence of alkali to prepare an alkaline dispersion liquid, then adding nano-cellulose into the alkaline dispersion liquid, dispersing and emulsifying the nano-cellulose, finally adding a layered two-dimensional material into the alkaline dispersion liquid to prepare an aqueous dispersion liquid of the layered two-dimensional material, and shearing and dispersing the aqueous dispersion liquid;

(2) and treating the sheared and dispersed layered two-dimensional material aqueous dispersion liquid in one or more mechanical modes of high-pressure homogenization treatment, ultrasonic treatment, high-pressure micro-jet impact and grinding treatment to mechanically strip the layered two-dimensional material so as to obtain the aqueous dispersion solution of the few-layer two-dimensional material.

(3) And mixing the aqueous dispersion liquid of the few-layer two-dimensional material with a spinning solution of cellulose fibers, and then spinning to prepare the few-layer two-dimensional material modified cellulose fibers.

2. The method of claim 1, wherein the dispersant is selected from serrated dispersants.

3. The method of claim 2, wherein the serrated dispersing agent is selected from one or more of amino silicone oil, polyoxyethylene siloxane.

4. The method of claim 1, wherein the layered two-dimensional material is selected from one or more of two-dimensional materials such as graphite, graphite oxide, hexagonal boron nitride, molybdenum disulfide, zirconium phosphate, and the like.

5. The method of claim 1, wherein the few-layer two-dimensional material is selected from one or more of graphene, graphite oxide, few-layer hexagonal boron nitride, few-layer molybdenum disulfide, few-layer zirconium phosphate, and the like two-dimensional materials.

6. The method of claim 1, wherein the cellulosic fibers are selected from one or more of viscose, lyocell, cuprammonium, bamboo, acetate.

7. The method of claim 1, wherein the nanocellulose is less than 100nm in diameter and less than 2um in length.

8. The process of claim 1, wherein the alkaline dispersion of step (1) has a pH of from 10 to 14.

9. The method of claim 1, wherein the weight ratio of the nanocellulose to the dispersant in step (1) is 0.5-1.5:0.5-1.5, and the sum of the nanocellulose and the dispersant is 5-30% of the layered two-dimensional material.

10. The preparation method according to claim 1, wherein the few-layer two-dimensional material in the step (3) accounts for 0.05-5% of the cellulose content.

11. Use of a dispersant, nanocellulose and a few-layer two-dimensional material for modifying cellulose fibres.

12. Use according to claim 11, wherein the dispersant is selected from serrated dispersants.

13. Use according to claim 12, wherein the serrated dispersing agent is selected from one or more of amino silicone oil, polyoxyethylene siloxane.

14. The use according to claim 11, wherein the few-layer two-dimensional material is selected from one or more of graphene, graphene oxide, hexagonal boron nitride, few-layer molybdenum disulfide, few-layer zirconium phosphate, and the like two-dimensional materials.

15. Use according to claim 11, wherein the cellulose fibres are selected from one or more of viscose, lyocell, cuprammonium, bamboo and acetate fibres.

Technical Field

The invention belongs to the field of material application, and particularly relates to a method for modifying cellulose fibers by using a few-layer two-dimensional material, and application of a dispersing agent, nano-cellulose and the few-layer two-dimensional material in modification of the cellulose fibers.

Background

A two-dimensional material is a crystalline material consisting of a monolayer of atoms with a thickness of a few nanometers or less. Since the first two-dimensional material, graphene, appeared in 2004, about 700 two-dimensional materials have been experimentally or theoretically certified to stably exist so far. These two-dimensional materials have relatively high surface activity, "surface-to-interior" and surface modification, element substitution or doping all have a substantial effect on the properties of the material itself, and have unique electrical, optical properties and two-dimensional structures, some of which have been used in photovoltaic, semiconductor, electrode and biological monitoring applications. The unique properties, specific structure and large potential market of these two-dimensional materials have attracted research interest to many scientists.

Two-dimensional materials such as graphene have good application in the textile field due to the characteristics of antibiosis, far infrared, electric conduction, heat conduction, antistatic property and the like, and graphene modified viscose fiber, graphene modified nylon, graphene modified terylene, graphene modified acrylic fiber and the like are already available in the market at present. In the prior art, for example, chinese patent publication No. CN 105603554a [ marquis et al, the invention name: a graphene functionalized cellulose fiber and a preparation method thereof are disclosed, namely 2016, 05, 25, a publication date. In the prior art, many reports of methods for preparing two-dimensional material dispersions have appeared, for example, chinese patent publication No. CN 109553095 a [ yellow treasure bolt, etc., title of the invention: a preparation method of a high-concentration graphene aqueous solution is disclosed in publication No. 2019, 4 and 2.4.4.8.A method for dispersing and grinding graphene by using a dispersing agent such as sodium carboxymethylcellulose; chinese patent publication No. CN 109956499 a [ sun cream, etc., inventive name: the stripping method of the two-dimensional material comprises the following steps: published 2019, 7 and 2/7) discloses a method for preparing two-dimensional materials such as molybdenum disulfide, boron nitride and the like by ball milling sodium dodecyl benzene sulfonate. The dispersant prepared into the two-dimensional material dispersion can play a good role in dispersion stability in the cellulose fiber spinning solution, but the dispersant does not help to improve the performance of the two-dimensional material composite cellulose fiber many times, and even sometimes causes that the tensile strength, the tensile strength and the like of the modified cellulose fiber are reduced to a certain extent, which is unfavorable for the application of the cellulose fiber.

The diameter of the nano-cellulose is between 1nm and 100nm, the smaller the particle size is, the larger the surface area is, and the surface particles lack coordination of adjacent atoms, so that the surface energy is increased and is extremely unstable, the nano-cellulose is easy to be combined with other atoms, and the nano-cellulose shows stronger activity. The application of the nano-fiber is very wide, for example, the nano-fiber is implanted into the surface of the fabric to form a layer of stable gas film, so that the amphiphobic interface fabric is prepared, and the fabric can be waterproof, oil-proof and antifouling; the fabric of the high-grade protective clothing made of the nano-fiber is porous and provided with a film, so that the high-grade protective clothing not only can enable air to permeate and has breathability, but also can block wind and filter fine particles, has barrier property to aerosol, and can prevent biochemical weapons and toxic substances. In addition, the nano-cellulose can also be used for purification, filtration and the like of products such as chemical engineering, medicines and the like. Meanwhile, the surface of the nano-cellulose is provided with a large amount of hydroxyl, the nano-cellulose can react with a plurality of hydroxyl materials to form gel in a solution, the nano-cellulose can react with the hydroxyl on the surface of the two-dimensional material to stabilize the dispersion of the two-dimensional material, and can react with the cellulose fiber to connect the two-dimensional material and the cellulose fiber, so that the two-dimensional material modified cellulose fiber is realized, the performance of the cellulose fiber can be improved, and the excellent function of the two-dimensional material is introduced. Yubing Zhou et al (a printed, recycled, ultra-stranded, and ultra-gauge graphite structural materials Today 2019) utilize the secondary bonding (e.g., hydrogen bonding) that exists between graphite and nanocellulose to realize a new structural material that is low in cost, high in performance, and completely degradable, and has a density and cost comparable to plastics, but a strength higher than steel; hongli Zhu et al (high thermal Conductive Papers with a permeable Layered Boron nitride nanosheets. ACS NANO 2014, 10, 3606-. From the literature, it is found that the properties of both the nanocellulose and the two-dimensional material are improved, but when we test the nanocellulose and the two-dimensional material into the spinning solution of the cellulose fiber, the mixed solution is easy to block the spinneret orifice during spinning.

Disclosure of Invention

Aiming at the problems of the application of the existing two-dimensional material in the modified cellulose fiber, the invention provides a method for modifying the cellulose fiber by using a few-layer two-dimensional material.

The method for modifying the cellulose fiber by the few-layer two-dimensional material comprises the following steps:

(1) dispersing a dispersing agent in water in the presence of alkali to prepare an alkaline dispersion liquid, then adding nano-cellulose into the alkaline dispersion liquid for dispersion and emulsification, finally adding a layered two-dimensional material into the alkaline dispersion liquid to prepare an aqueous dispersion liquid of the layered two-dimensional material, and shearing and dispersing the aqueous dispersion liquid;

(2) and treating the sheared and dispersed layered two-dimensional material aqueous dispersion liquid in one or more mechanical modes of high-pressure homogenization treatment, ultrasonic treatment, high-pressure micro-jet impact and grinding treatment to mechanically strip the layered two-dimensional material so as to obtain the aqueous dispersion solution of the few-layer two-dimensional material.

(3) And mixing the aqueous dispersion liquid of the few-layer two-dimensional material with the spinning solution of the cellulose fiber, and then spinning to prepare the two-dimensional material cellulose fiber.

In a preferred embodiment of the invention, the dispersant is a serrated dispersant in the process for modifying cellulose fibers with a two-dimensional material.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber with two-dimensional material, the serrated dispersant is selected from one or more of amino silicone oil, polyoxyethylene silicone oil and polyoxyethylene siloxane.

In a preferred embodiment of the invention, in the method for modifying cellulose fibers with a two-dimensional material, the layered two-dimensional material is selected from one or more of the layered materials such as graphite, hexagonal boron nitride, molybdenum disulfide, zirconium phosphate, and the like.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber with two-dimensional material, the few-layer two-dimensional material is selected from one or more of graphene, few-layer hexagonal boron nitride, few-layer molybdenum disulfide and few-layer zirconium phosphate.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber by two-dimensional material, the cellulose fiber is selected from one or more of viscose fiber, lyocell fiber, cuprammonium fiber, bamboo fiber and acetate fiber.

In a preferred embodiment of the invention, in the method for modifying cellulose fibers with a two-dimensional material, the nanocellulose is less than 100nm in diameter and less than 2um in length.

In a preferred embodiment of the present invention, in the method for modifying cellulose fibers with a two-dimensional material, the pH of the alkaline dispersion in step (1) is 10 to 14.

In a preferred embodiment of the present invention, in the method for modifying cellulose fibers with a two-dimensional material, the alkaline modifier in step (1) is an organic base or an inorganic base. In a preferred embodiment of the invention, the organic base is selected from the group consisting of ammonia and/or alcohol amines. In a preferred embodiment of the present invention, the inorganic base is selected from one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide. In a more preferred embodiment of the present invention, in the method for modifying cellulose fibers with a two-dimensional material, the alkaline modifier in step (1) is selected from sodium hydroxide.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber with a two-dimensional material, the weight ratio of the nanocellulose to the dispersant in step (1) is 0.5-1.5: 0.5-1.5. More preferably, the weight ratio of the nanocellulose to the dispersant is 1: 1.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber by two-dimensional material, the sum of the weight of the nano-cellulose and the dispersant in step (1) is 5-30% of the weight of the layered two-dimensional material.

In a preferred embodiment of the present invention, in the method for modifying cellulose fibers with a two-dimensional material, the number of layers of the few-layer two-dimensional material in the step (2) is 1 to 10; more preferably, the number of the few-layer two-dimensional material layers is 3-8.

In a preferred embodiment of the present invention, in the method for modifying cellulose fiber with a two-dimensional material, the temperature of mechanically treating the aqueous dispersion of the layered two-dimensional material after shear dispersion in step (2) is 10 to 80 ℃; more preferably, the temperature is 20-50 ℃.

In a preferred embodiment of the present invention, in the method for modifying cellulose fibers with a two-dimensional material, the weight of the few-layer two-dimensional material in step (3) is 0.05-5% of the weight of the cellulose fibers. More preferably, the weight of the few-ply two-dimensional material is 0.5-3% of the weight of the cellulose fibers.

The invention also provides the use of dispersants, nanocellulose and few-layer two-dimensional materials in modifying cellulose fibres.

In a preferred embodiment of the invention, the use of a dispersant selected from the group consisting of saw-tooth dispersants, nanocellulose and few-ply two-dimensional materials in modifying cellulose fibres.

In a preferred embodiment of the invention, the use of a dispersant selected from one or more of amino silicone oil, polyoxyethylene siloxane, nanocellulose and a few-layer two-dimensional material in modifying cellulose fibres.

In a preferred embodiment of the invention, the use of a dispersant, nanocellulose and a few-layer two-dimensional material selected from one or more of graphene, few-layer hexagonal boron nitride, few-layer molybdenum disulphide, few-layer zirconium phosphate in modified cellulose fibres.

In a preferred embodiment of the invention, in the use of a dispersant, nanocellulose and a few-layer two-dimensional material in modified cellulose fibres, the number of layers of said few-layer two-dimensional material is from 1 to 10; more preferably, the number of the few-layer two-dimensional material layers is 3-8.

In a preferred embodiment of the invention, the use of a dispersant, nanocellulose and a few-ply two-dimensional material in modifying cellulose fibres selected from one or more of viscose, lyocell, cuprammonium, bamboo, acetate fibres.

In a preferred embodiment of the invention, in the use of a dispersant, nanocellulose and a few-ply two-dimensional material for modifying cellulose fibres, the mass ratio of nanocellulose to dispersant is from 0.5 to 1.5:0.5 to 1.5. More preferably, the mass ratio of the nanocellulose to the dispersant is 1: 1.

In a preferred embodiment of the invention, in the use of a dispersant, nanocellulose and a few-ply two-dimensional material in modifying cellulose fibres, the sum of the weight of the nanocellulose and the dispersant is between 5 and 30% of the weight of the few-ply two-dimensional material.

In a preferred embodiment of the invention, the dispersant, the nanocellulose and the few-ply two-dimensional material are used in modified cellulose fibres, the weight of the few-ply two-dimensional material being between 0.05 and 5% of the weight of the cellulose fibres. More preferably, the weight of the few-ply two-dimensional material is 0.5-3% of the weight of the cellulose fibers.

Compared with the existing method for modifying the cellulose fiber by using the dispersant such as sodium carboxymethylcellulose and polyvinylpyrrolidone in the two-dimensional material modified cellulose fiber, the method provided by the invention has the advantages that the modified cellulose fiber prepared by modifying the nano cellulose fiber by using the dispersant, the nano cellulose and the few-layer two-dimensional material (such as graphene, graphene oxide, hexagonal boron nitride, molybdenum disulfide, zirconium phosphate and the like) has good dry and wet strength, elongation at break, light resistance and wear resistance. This is because, in the conventional method of modifying cellulose fibers with a two-dimensional material, these dispersants merely serve to disperse the two-dimensional material and do not improve the properties of the cellulose fibers, whereas in the method of the present invention, because the addition of the nano-cellulose enables the surfaces of the few-layer two-dimensional materials to be connected with a large number of nano-cellulose molecules, thereby leading the surface of the two-dimensional material with a small number of polar groups such as hydroxyl and the like, and the dispersant, especially the serrated dispersant, has extremely plastic molecular structure, after the polar groups on the surface of the two-dimensional material with few layers are combined, the directional adsorption of the two-dimensional material on the surface of the cellulose fiber can be improved, meanwhile, the dispersing agent can also assist the nanocellulose to disperse and modify the two-dimensional material (namely, a grafted bridge is formed between the two-dimensional material and the nanocellulose, so that the two-dimensional material and the nanocellulose can be better combined), and finally the lifting performance of the cellulose fibers is improved.

Detailed Description

In the present invention, "two-dimensional material" refers to a two-dimensional atomic crystal material "that is, a material in which electrons can move freely (planar motion) only in two dimensions, not on a nanometer scale (1 to 100 nm).

In the present invention, the "number of layers of the few-layer two-dimensional material" is 1 to 10 layers "obtained by mechanically peeling one or more of layered two-dimensional materials, for example, graphite oxide, hexagonal boron nitride, molybdenum disulfide, zirconium phosphate, and the like.

In the present invention, "dispersant" means a surfactant capable of changing the surface activity of a two-dimensional material, including, but not limited to, sodium carboxymethylcellulose, sodium lauryl sulfate, alkyl glycosides, sodium cholate, lignosulfonate, span, cellulose, styrene sulfonate, polyvinylpyrrolidone, serrated dispersants, and the like. According to the invention, the dispersant can change the surface activity of the few-layer two-dimensional material to enable the surface activity to be better in water, and can form a grafting bridge between the few-layer two-dimensional material and the nano-cellulose to enable the few-layer two-dimensional material and the nano-cellulose to be better combined, and meanwhile, the directional adsorption of the few-layer two-dimensional material combined with the nano-cellulose on the surface of cellulose fiber is improved, and finally the lifting performance of the cellulose fiber is improved.

In the invention, the serrated dispersant is a dispersant in a serrated shape, has an extremely plastic molecular structure, and can form a grafted bridge between a few layers of two-dimensional materials and nano-cellulose, so that the few layers of two-dimensional materials are better combined with the nano-cellulose, the directional adsorption of the few layers of two-dimensional materials combined with the nano-cellulose on the surface of cellulose fibers is improved, and the tensile property of the cellulose fibers is finally improved.

In the present invention, "cellulose fibers" are textile fibers used in the textile field and include both long fibers and short fibers. Textile fibers useful as the cellulosic fibers of the present invention include, but are not limited to, one or more of viscose, lyocell, cuprammonium, bamboo, acetate fibers. In the method for modifying cellulose fiber by two-dimensional material of the invention, the cellulose fiber needs to be prepared into spinning solution according to the conventional method.

In the present invention, the "alkalinity adjuster" may be an inorganic alkaline substance or an organic alkaline substance soluble in water. Inorganic alkaline substances useful as alkaline adjusters according to the present invention include, but are not limited to, sodium hydroxide, potassium hydroxide, and the like. Organic alkaline substances useful as alkaline adjusters according to the present invention include, but are not limited to, ammonia, alcohol amines, and the like.

In the present invention, "plural" means two or more.

The present invention is further described below in conjunction with specific embodiments, it being understood that the following examples are intended only to provide further details of the best modes of practicing the invention and should not be interpreted as limiting the scope of the invention. Experimental procedures in the following examples, where specific conditions are not specified, are generally in accordance with conventional procedures and conditions, or with conditions recommended by the manufacturer. Unless otherwise indicated, percentages and parts are by weight.

The manufacturer of the nanocellulose used in the following examples is northern century cellulose technology development ltd, model number: Nano-Cel); the manufacturer: TESCAN CHINA, type: RISE Microscope), the instruments used for transmission electron microscopy analysis are: (FET-Tencnai G2F 20S-7 WIN).