Process for producing long titanium oxide fibers of the rutile type

Abstract

The application discloses a preparation method of rutile titanium oxide long fibers, and belongs to the field of titanium oxide preparation. The preparation steps comprise the following steps: mixing titanium chloride, ethylene glycol and ethanolamine, stirring and refluxing, filtering to obtain a clear and transparent solution, rotary evaporation of the clear and transparent solution to obtain a concentrated rectification product, mixing the rectification product with ethyl methyl ketone, adding deionized water into the mixture, stirring and refluxing to obtain an organic titanium solution; adding polyvinyl alcohol into the organic titanium solution, uniformly stirring to obtain a stable spinning solution, electrospinning, heat treating the fibers after spinning to obtain rutile titanium oxide long fibers. The titanium oxide fibers prepared by the method are of rutile structure, the fibers are continuous, not adhered to each other and smooth in surface, the preparation method is simple, suitable for industrialization, and has a wide application prospect.

Description

Technical Field

[0001] This invention relates to a method for preparing titanium dioxide fibers, and more particularly to a method for preparing rutile titanium dioxide long fibers. Background Technology

[0002] Rutile titanium dioxide is the most thermodynamically stable of the three crystal forms of titanium dioxide. It does not decompose or transform at high temperatures and exhibits good chemical inertness. Rutile titanium dioxide also possesses excellent light scattering and reflection properties, a high refractive index, and is non-toxic. Titanium dioxide fiber materials not only possess the inherent properties of titanium dioxide but also offer greater ease of use than titanium dioxide powder and films, such as high recyclability and reusability. Therefore, titanium dioxide fiber materials have broader application prospects and can be used in various fields.

[0003] A common method for preparing titanium dioxide fibers is to prepare a titanium-containing sol, followed by electrospinning and calcination to obtain the fiber material. While this sol-gel method is simple, the resulting spinning precursor solution is difficult to preserve and prone to hydrolysis over time, which is detrimental to mass production and continuous operation. Furthermore, if the spun fibers are not heat-treated promptly, they may pulverize, and calcination can cause fiber adhesion and surface roughness, thus affecting the material's performance, including interfacial properties when combined with other materials. Current research focuses primarily on anatase titanium dioxide, while rutile titanium dioxide, especially rutile titanium dioxide fiber materials, has received less attention. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for preparing rutile titanium dioxide long fibers, which involves electrospinning with a stable precursor solution followed by heat treatment to obtain a smooth rutile titanium dioxide long fiber material.

[0005] To achieve the above-mentioned objectives, the present invention proposes the following technical solution: a method for preparing rutile titanium dioxide long fibers, comprising the following steps:

[0006] S1. Titanium chloride, ethylene glycol and ethanolamine are mixed and stirred under reflux at a certain temperature, and then filtered to obtain a clear and transparent solution;

[0007] S2. The clear and transparent solution is rotary evaporated to obtain a concentrated distillation product, and the concentrated distillation product is mixed with ethyl methyl ketone and refluxed at a certain temperature;

[0008] S3. Add deionized water to S2, stir and reflux to obtain an organic titanium solution;

[0009] S4. Add polyvinyl alcohol to the prepared organic titanium solution, stir evenly to obtain a spinning solution, and perform electrospinning.

[0010] S5. Heat-treat the spun fibers to obtain rutile titanium dioxide long fibers.

[0011] Preferably, in step S2, the distillation product is a titanium alkoxide.

[0012] Preferably, the distillation product is chelated with the ethyl methyl ketone under certain conditions to obtain a titanium-containing complex.

[0013] Preferably, the titanium-containing complex undergoes a condensation reaction upon addition of deionized water to obtain a linear organotitanium solution, wherein the molecular formula of the linear organotitanium is:

[0014]

[0015] Preferably, in step S1, the initial molar ratio of titanium chloride, ethylene glycol, and ethanolamine is (1-2):(0.4-1):(4-9).

[0016] Preferably, in step S1, the preparation temperature of the clear and transparent solution is room temperature, and the stirring and reflux time is 3-5 hours.

[0017] Preferably, in step S2, the molar ratio of the amount of ethyl methyl ketone added to ethanolamine is (0.9-1.6):1.

[0018] Preferably, in step S2, the reflux temperature of the concentrated distillation product and ethyl methyl ketone is 45-65°C, and the reflux time is 2-4 hours.

[0019] Preferably, in step S3, the molar ratio of the amount of deionized water added to ethanolamine is (1.2-2.1):1, and the stirring and reflux time is 1-3 hours.

[0020] Preferably, in step S5, the heat treatment conditions for the fiber are as follows: in an air atmosphere, first heat treatment is carried out at 150℃-250℃ for 4-12 hours, then the temperature is raised to 800℃-1000℃ and held for 1-3 hours, and finally the fiber is cooled in the furnace.

[0021] Preferably, in step S4, the electrospinning is carried out under conventional conditions, and the spinning voltage is 12-15KV.

[0022] In the preparation method of this invention, titanium chloride, ethylene glycol, and ethanolamine react to prepare a titanium alkoxide. After filtration, the alkoxide is rotary evaporated to remove excess reactants. The distilled titanium alkoxide is then chelated with ethyl methyl ketone under certain conditions to obtain a titanium-containing complex. By introducing an appropriate amount of deionized water, the titanium-containing complex undergoes a condensation reaction to obtain a linear organotitanium solution. The molecular formula of this linear organotitanium is:

[0023]

[0024] Obtaining linear organotitanium facilitates the preparation of long fiber materials. Adding a certain amount of polyvinyl alcohol to the prepared organotitanium solution allows for further bonding between the polyvinyl alcohol and organotitanium through hydrogen bonding after dissolution, thus forming a stable spinning solution. This also improves the spinning ability of the precursor solution, contributing to enhanced fiber structure uniformity and the acquisition of smooth, continuous fiber materials. After appropriate heat treatment, the spun fibers yield rutile titanium dioxide long fibers.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. This invention obtains linear organic titanium by selecting specific reaction raw materials, which is easy to spin, and the fiber morphology obtained by heat treatment after spinning is continuous and smooth.

[0027] 2. The raw materials are simple, widely available, and easy to obtain. The utilization rate of titanium sources is high. The use of specific small organic molecules as synthetic raw materials improves the yield of materials.

[0028] 3. The organic titanium obtained by this invention is stable, does not hydrolyze, and can be re-dissolved after solidification, making it easy to store for a long time.

[0029] 4. By controlling process conditions such as spinning solution concentration, spinning voltage, and heat treatment temperature, rutile titanium oxide fibers with different sizes ranging from 0.5 to 1.0 μm can be obtained, which broadens the preparation ideas and application fields of titanium oxide fibers. The process is simple and provides support for its industrialization. Attached Figure Description

[0030] Figure 1 This is a SEM image of the rutile titanium dioxide long fibers prepared in Example 1;

[0031] Figure 2 This is the XRD pattern of the rutile titanium dioxide long fibers prepared in Example 1. Detailed Implementation

[0032] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0033] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated ingredients or components without excluding other ingredients or other components.

[0034] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0035] Example 1

[0036] Titanium chloride, ethylene glycol, and ethanolamine were mixed in a molar ratio of 1:0.4:4, stirred and refluxed at room temperature for 3 hours, and then filtered to obtain a clear and transparent solution.

[0037] Then, the clear, transparent solution was subjected to rotary evaporation to obtain a concentrated distillation product;

[0038] Based on the amount of ethanolamine added, ethyl methyl ketone was added to the distilled solution at a molar ratio of 0.9:1 to ethyl methyl ketone. After refluxing at 45°C for 4 hours, deionized water was added dropwise at a molar ratio of 1.2:1 to deionized water. After stirring and refluxing for another hour, an organic titanium solution was obtained.

[0039] Polyvinyl alcohol was added to the prepared organic titanium solution, and after stirring evenly, a stable spinning solution was obtained, which was then subjected to electrospinning.

[0040] The spun fibers were first held at 150°C for 12 hours in air, then heated to 800°C and held for 3 hours. After natural cooling in the furnace, rutile titanium dioxide long fibers were obtained. Figure 1 , Figure 2 As shown, the rutile titanium dioxide long fibers prepared in this embodiment are smooth, continuous, and non-adhesive, with a size of approximately 0.7 μm.

[0041] Example 2

[0042] Titanium chloride, ethylene glycol and ethanolamine were mixed in a molar ratio of 1.5:1:6, stirred and refluxed at room temperature for 4 hours, and then filtered to obtain a clear and transparent solution.

[0043] The clear, transparent solution was subjected to rotary evaporation to obtain a concentrated distillation product.

[0044] Based on the amount of ethanolamine added, ethyl methyl ketone was added to the distilled solution at a molar ratio of 1.4:1 to ethyl methyl ketone. After refluxing at 55°C for 3 hours, deionized water was added dropwise at a molar ratio of 1.7:1 to deionized water. After stirring and refluxing for another 2 hours, an organic titanium solution was obtained.

[0045] Polyvinyl alcohol was added to the prepared organic titanium solution, and after stirring evenly, a stable spinning solution was obtained, which was then subjected to electrospinning.

[0046] After spinning, the fibers are first kept at 200°C for 8 hours in air, then heated to 900°C and kept at 900°C for 2 hours. After natural cooling in the furnace, smooth, continuous, and non-adhesive rutile titanium dioxide long fibers with a size of about 0.5 μm are obtained.

[0047] Example 3

[0048] Titanium chloride, ethylene glycol, and ethanolamine were mixed in a molar ratio of 2:0.6:9, stirred and refluxed at room temperature for 5 hours, and then filtered to obtain a clear and transparent solution.

[0049] The clear, transparent solution was subjected to rotary evaporation to obtain a concentrated distillation product.

[0050] Based on the amount of ethanolamine added, ethyl methyl ketone was added to the distilled solution at a molar ratio of 1.6:1 to ethyl methyl ketone. After refluxing at 65°C for 2 hours, deionized water was added dropwise at a molar ratio of 2.1:1 to deionized water. After stirring and refluxing for another 3 hours, an organic titanium solution was obtained.

[0051] Polyvinyl alcohol was added to the prepared organic titanium solution, and after stirring evenly, a stable spinning solution was obtained, which was then subjected to electrospinning.

[0052] After spinning, the fibers are first kept at 250°C for 4 hours in air, then heated to 1000°C and kept for 1 hour. After natural cooling in the furnace, smooth, continuous, and non-adhesive rutile titanium dioxide long fibers with a size of about 1 μm are obtained.

[0053] The description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for preparing rutile titanium dioxide long fibers, characterized in that, Includes the following steps: S1. Titanium chloride, ethylene glycol and ethanolamine are mixed and stirred under reflux at a certain temperature, and then filtered to obtain a clear and transparent solution; S2. The clear and transparent solution is rotary evaporated to obtain a concentrated distillation product, and the concentrated distillation product is mixed with ethyl methyl ketone and refluxed at a certain temperature; S3. Add deionized water to S2, stir and reflux to obtain an organic titanium solution; S4. Add polyvinyl alcohol to the prepared organic titanium solution, stir evenly to obtain a spinning solution, and perform electrospinning. S5. Heat-treat the spun fibers to obtain rutile titanium dioxide long fibers. In S2, the distillation product is a titanium alkoxide; The distillation product is chelated and coordinated with the ethyl methyl ketone under certain conditions to obtain a titanium-containing complex. The titanium-containing complex undergoes a condensation reaction upon addition of deionized water to obtain a linear organotitanium solution, wherein the molecular formula of the linear organotitanium is:

2. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In S1, the initial molar ratio of titanium chloride, ethylene glycol and ethanolamine is (1-2):(0.4-1):(4-9).

3. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In step S1, the preparation temperature of the clear and transparent solution is room temperature, and the stirring and reflux time is 3-5 hours.

4. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In step S2, the molar ratio of the amount of ethyl methyl ketone added to ethanolamine is (0.9-1.6):

1.

5. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In step S2, the concentrated distillation product is refluxed with ethyl methyl ketone at a temperature of 45-65°C for 2-4 hours.

6. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In step S3, the molar ratio of deionized water to ethanolamine is (1.2-2.1):1, and the stirring and reflux time is 1-3 hours.

7. The method for preparing rutile titanium dioxide long fibers according to claim 1, characterized in that, In step S5, the heat treatment conditions for the fiber are as follows: in an air atmosphere, first hold at 150℃-250℃ for 4-12 hours, then raise the temperature to 800℃-1000℃ and hold for 1-3 hours, and finally cool naturally in the furnace.

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