Water-based oil agent for carbon fibers with high heat resistance and preparation method of water-based oil agent

Abstract

The invention provides a water-based oil agent with high heat resistance for carbon fibers and a preparation method of the water-based oil agent, and belongs to the field of carbon fiber oil agents, the oil agent comprises the following components: 1-10 parts of polyether modified polydimethylsiloxane, 5-15 parts of phosphate modified polysiloxane, 50-80 parts of a high-temperature-resistant auxiliary agent, 10-15 parts of an emulsifier, 1-3 parts of an antistatic agent, 1-3 parts of a defoaming agent and 60-150 parts of deionized water; the prepared water-based oil agent for the carbon fiber is good in heat transfer capacity, when a carbon fiber precursor is coated and then is in a preheating stage, local high temperature can be quickly transferred, so that heating is uniform, and the problem of oil agent loss caused by the local high temperature is solved; experiments prove that the thermal decomposition loss is less than 13.5% in the pre-oxidation stage at 325 DEG C.

Description

Technical Field

[0001] The invention belongs to the field of carbon fiber oil agents, and specifically relates to an aqueous oil agent for carbon fiber with high heat resistance and a preparation method thereof. Background Art

[0002] The main function of the oil is to form a uniform film on the surface of the raw silk after spinning and washing, effectively preventing or eliminating static electricity caused by friction, reducing the friction coefficient, and giving the fiber smoothness, softness and other characteristics, so that the fiber has appropriate bundling, drafting, fiber separation, spinnability, oxidation resistance and heat resistance. Especially during the pre-oxidation period of 200-300℃, due to the sharp heat release of the cyclization reaction, the single fibers are often locally thermally bonded or hot-wired, and more seriously, it will cause local heat storage or overheating of the raw silk bundle, resulting in combustion.

[0003] Usually, epoxy is introduced to improve the heat resistance of polymethylsiloxane, increase the initial decomposition temperature of polymethylsiloxane, and better protect the carbon fiber during the carbonization and pre-oxidation stages. At present, polymethylsiloxane modified with multiple groups has appeared; however, there are still limitations on the high temperature resistance of the oil and the improvement of the performance of carbon fiber; the existing technology uses nanoparticles in carbon fiber oil to improve the mechanical properties of carbon fiber, but there is no record of how to improve the high temperature resistance of the oil and reduce the thermal decomposition loss of the oil, and the existing oil has poor water solubility.

[0004] Therefore, there is an urgent need for a simple, easily available aqueous oil for carbon fiber with a low thermal decomposition loss rate. Summary of the invention

[0005] In view of this, the object of the present invention is to provide an aqueous oil agent for carbon fiber with high heat resistance and a preparation method thereof. The obtained oil agent has good thermal conductivity, low thermal decomposition loss rate, strong ability to protect carbon fiber, high water solubility and little impact on the environment.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides an aqueous oil for carbon fiber with high heat resistance, which is made of the following components in parts by weight:

[0008] Polyether modified polydimethylsiloxane 1-10 parts

[0009] Phosphate modified polysiloxane 5-15 parts

[0010]

[0011] Preferably, the preparation method of the high temperature resistant auxiliary agent is:

[0012] (1) dispersing titanium carbide in an ethanol solution and then adding a hydrofluoric acid solution to react in an ice-water bath; after the reaction is completed, filtering and washing until neutral to obtain a product A;

[0013] (2) mixing a silane coupling agent with water and then adding activated titanium carbide to react; then filtering and washing to obtain product B;

[0014] (3) The product B is mixed with amino-modified polydimethylsiloxane to obtain a high temperature resistant auxiliary agent.

[0015] By adopting the above technical scheme, the titanium carbide (Ti3C2Tx) in the present invention has a large specific surface area with a two-dimensional structure, which can remain stable in a high temperature environment and is not prone to decomposition or failure. At the same time, the large surface area has excellent thermal conductivity, which can effectively transfer heat from a high temperature area to a low temperature area, effectively preventing the loss of oil agent caused by uneven heating during the preheating stage of preparing carbon fiber, and at the same time has a protective effect on the carbon fiber; and the modification of titanium carbide with amino-modified polydimethylsiloxane can improve the dispersibility of titanium carbide, and further the hydrophilicity and rich surface functional groups of titanium carbide make it easy to combine with other materials, improve the compatibility with other materials, help to form a uniform composite material, and improve the overall water solubility, so that the whole system uses water as a solvent to achieve an environmentally friendly effect; the introduction of titanium carbide can improve the surface wettability of carbon fiber, thereby enhancing its interface bonding performance with the polydimethylsiloxane matrix.

[0016] Preferably, in step (1), the volume ratio of the titanium carbide ethanol solution to the hydrofluoric acid solution is 1:1-3; and the particle size of the titanium carbide is 20-100 nm.

[0017] The concentration of the hydrofluoric acid solution is 2 mol / L.

[0018] Preferably, the reaction temperature in step (2) is 40-60° C. and the reaction time is 1-5 h;

[0019] The weight ratio of the silane coupling agent to the activated titanium carbide is 1:10.

[0020] Preferably, the reaction temperature in step (3) is 40-70° C. and the reaction time is 12-24 h.

[0021] The weight ratio of the product B to the amino-modified polydimethylsiloxane is 1:10-20.

[0022] Preferably, the amino-modified polydimethylsiloxane in step (3) is a side-chain epoxy-modified polydimethylsiloxane or a double-terminal epoxy-modified polydimethylsiloxane.

[0023] Preferably, the amino content is 0.05 to 1.5 mmol / g, and the viscosity at 25° C. is 20 to 20,000 mPa·s.

[0024] Preferably, the molecular weight of the polyether-modified polydimethylsiloxane is 2000-10000; the molecular weight of the phosphate-modified polysiloxane is 2000-3500.

[0025] Preferably, the emulsifier is isomeric alcohol polyoxyethylene ether, polyoxyethylene sorbitan ester or alkyl alcohol amide.

[0026] Preferably, the antistatic agent is polyethylene glycol fatty acid ester, polyoxyethylene laurate or sorbitan fatty acid ester.

[0027] Preferably, the defoaming agent is fatty alcohol polyoxyethylene ether, isopentanol, or diisobutyl carbinol.

[0028] In a second aspect, the present invention provides a method for preparing the above-mentioned aqueous oil agent for carbon fiber, comprising the following steps:

[0029] (1) weighing the raw materials according to the weight parts;

[0030] (2) The polyether-modified polydimethylsiloxane, the phosphate-modified polysiloxane and the high-temperature resistant auxiliary agent are mixed evenly, and then an emulsifier, an antistatic agent, a defoaming agent and deionized water are added for emulsification to obtain a water-based oil agent for carbon fiber with high heat resistance.

[0031] Preferably, the particle size of the aqueous oil agent for carbon fiber is 150-200 nm.

[0032] Contains at least the following beneficial technical effects:

[0033] 1) The carbon fiber prepared by the present invention has good heat transfer capacity with aqueous oil. When the carbon fiber precursor is coated, in the preheating stage, the local high temperature can be quickly transferred so that the heat is evenly distributed, reducing the problem of oil loss caused by local high temperature. Experiments have shown that in the pre-oxidation stage at 325°C, the thermal decomposition loss is less than 13.5%.

[0034] 2) The oil prepared by the present invention can improve the mechanical properties of carbon fiber, make its surface smooth and reduce fiber breakage.

[0035] 3) The preparation method of the oil prepared by the present invention is simple and can be used for industrial production. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is further illustrated by the following examples.

[0037] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the gist or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0039] In addition, it should be understood that although this specification is described according to the implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. These other implementation modes are also covered within the protection scope of the present invention.

[0040] It should also be understood that the specific embodiments described above are only used to explain the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the protection scope of the present invention / invention.

[0041] Example 1

[0042] This embodiment provides a method for preparing an aqueous oil agent for carbon fiber with high heat resistance, the steps are:

[0043] S1. Preparation of high temperature resistant auxiliary agent:

[0044] Titanium carbide (particle size 20 nm) was dispersed in an ethanol solution and then a 2 mol / L hydrofluoric acid solution was added to react in an ice-water bath; after the reaction was completed, the product A was filtered and washed to neutrality; wherein the volume ratio of the titanium carbide ethanol solution to the hydrofluoric acid solution was 1:1;

[0045] The silane coupling agent and water are mixed, and then activated titanium carbide is added to react at 40° C. for 1 hour; then the product B is obtained by filtering and washing; wherein the weight ratio of the silane coupling agent to the activated titanium carbide is 1:10.

[0046] The product B and amino-modified polydimethylsiloxane are mixed at 40°C and reacted for 12 hours to obtain a high temperature resistant auxiliary agent; wherein the weight ratio of the product B to the amino-modified polydimethylsiloxane is 1:10; the amino-modified polydimethylsiloxane is a side chain epoxy-modified polydimethylsiloxane; the amino content is 0.1 mmol / g, and the viscosity at 25°C is 245 mpa·s.

[0047] S2. Weigh the following raw materials according to weight ratio

[0048]

[0049] The molecular weight of the polyether-modified polydimethylsiloxane is 2000; the molecular weight of the phosphate-modified polysiloxane is 2000.

[0050] S3. The polyether-modified polydimethylsiloxane, phosphate-modified polysiloxane and high-temperature resistant auxiliary agent are mixed evenly, and then an emulsifier, an antistatic agent, a defoaming agent and deionized water are added for emulsification to obtain an aqueous oil agent for carbon fiber with a particle size of 150nm and high heat resistance.

[0051] Example 2

[0052] This embodiment provides a method for preparing an aqueous oil agent for carbon fiber with high heat resistance, the steps are:

[0053] S1. Preparation of high temperature resistant auxiliary agent:

[0054] Titanium carbide (particle size 50 nm) was dispersed in an ethanol solution and then a 2 mol / L hydrofluoric acid solution was added to react in an ice-water bath; after the reaction was completed, the product A was filtered and washed to neutrality; wherein the volume ratio of the titanium carbide ethanol solution to the hydrofluoric acid solution was 1:2;

[0055] The silane coupling agent and water are mixed, and then activated titanium carbide is added to react at 50° C. for 3 hours; then the product B is obtained by filtering and washing; wherein the weight ratio of the silane coupling agent to the activated titanium carbide is 1:10.

[0056] The product B and amino-modified polydimethylsiloxane are mixed at 50°C and reacted for 18 hours to obtain a high temperature resistant auxiliary agent; wherein the weight ratio of the product B to the amino-modified polydimethylsiloxane is 1:15; the amino-modified polydimethylsiloxane is a double-terminal epoxy-modified polydimethylsiloxane; the amino content is 0.5 mmol / g, and the viscosity at 25°C is 1000 mpa·s.

[0057] S2. Weigh the following raw materials according to weight ratio

[0058]

[0059] The molecular weight of the polyether-modified polydimethylsiloxane is 5000; the molecular weight of the phosphate-modified polysiloxane is 3000.

[0060] S3. The polyether-modified polydimethylsiloxane, phosphate-modified polysiloxane and high-temperature resistant auxiliary agent are mixed evenly, and then an emulsifier, an antistatic agent, a defoaming agent and deionized water are added for emulsification to obtain an aqueous oil agent for carbon fiber with a particle size of 160 nm and high heat resistance.

[0061] Example 3

[0062] This embodiment provides a method for preparing an aqueous oil agent for carbon fiber with high heat resistance, the steps are:

[0063] S1. Preparation of high temperature resistant auxiliary agent:

[0064] Disperse titanium carbide (particle size 100 nm) in an ethanol solution and then add 2 mol / L hydrofluoric acid solution to react in an ice-water bath; after the reaction is completed, filter and wash until neutral to obtain product A; wherein the volume ratio of the titanium carbide ethanol solution to the hydrofluoric acid solution is 1:3;

[0065] The silane coupling agent and water are mixed, and then activated titanium carbide is added to react at 60° C. for 5 hours; then the product B is obtained by filtering and washing; wherein the weight ratio of the silane coupling agent to the activated titanium carbide is 1:10.

[0066] The product B and amino-modified polydimethylsiloxane are mixed at 70°C and reacted for 24 hours to obtain a high temperature resistant auxiliary agent; wherein the weight ratio of the product B to the amino-modified polydimethylsiloxane is 1:20; the amino-modified polydimethylsiloxane is a side chain epoxy-modified polydimethylsiloxane; the amino content is 1.5 mmol / g, and the viscosity at 25°C is 15000 mpa·s.

[0067] S2. Weigh the following raw materials according to weight ratio

[0068]

[0069] The molecular weight of the polyether-modified polydimethylsiloxane is 10,000; the molecular weight of the phosphate-modified polysiloxane is 3,500.

[0070] S3. The polyether-modified polydimethylsiloxane, phosphate-modified polysiloxane and high-temperature resistant auxiliary agent are mixed evenly, and then an emulsifier, an antistatic agent, a defoaming agent and deionized water are added for emulsification to obtain an aqueous oil agent for carbon fiber with a particle size of 200 nm and high heat resistance.

[0071] Comparative Example 1

[0072] The preparation method of this comparative example is the same as that of Example 2, except that the high temperature resistant auxiliary agent is amino-modified polydimethylsiloxane; the weight ratio of amino-modified polydimethylsiloxane is 1:15; the amino-modified polydimethylsiloxane is double-terminal epoxy-modified polydimethylsiloxane; the amino content is 0.5 mmol / g, and the viscosity at 25°C is 1000 mpa·s.

[0073] Comparative Example 2

[0074] The preparation method of this comparative example is the same as that of Example 2, except that the high temperature resistant auxiliary agent is titanium carbide (particle size 50 nm) and amino-modified polydimethylsiloxane mixed in a mass ratio of 1:15;

[0075] The amino-modified polydimethylsiloxane is a double-terminal epoxy-modified polydimethylsiloxane; the amino content is 0.5 mmol / g, and the viscosity at 25° C. is 1000 mpa·s.

[0076] Comparative Example 3

[0077] The preparation method of this comparative example is the same as that of Example 2, except that no high temperature resistant auxiliary agent is added.

[0078] Experimental example

[0079] The performance of the oils obtained in Examples 1 to 3 and Comparative Examples 1 to 2 was tested, and 12K tow carbon fibers were prepared using the oils for testing, as shown in Table 1.

[0080] Table 1

[0081]

[0082] As shown in Table 1, the high temperature resistant auxiliary agent in Examples 1 to 3 of the present invention can significantly reduce the loss of the oil agent during pre-oxidation, and has a promoting effect on the performance of the carbon fiber.

[0083] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A water-based oil for carbon fiber with high heat resistance, characterized in that: Made from the following components in parts by weight:

2. The aqueous oil for carbon fiber according to claim 1, characterized in that: The preparation method of the high temperature resistant auxiliary agent is: (1) dispersing titanium carbide in an ethanol solution and then adding a hydrofluoric acid solution to react in an ice-water bath; after the reaction is completed, filtering and washing until neutral to obtain a product A; (2) mixing a silane coupling agent with water and then adding activated titanium carbide to react; then filtering and washing to obtain product B; (3) The product B is mixed with amino-modified polydimethylsiloxane to obtain a high temperature resistant auxiliary agent.

3. The aqueous oil for carbon fiber according to claim 2, characterized in that: In the step (1), the volume ratio of the titanium carbide ethanol solution to the hydrofluoric acid solution is 1:1-3; The concentration of the hydrofluoric acid solution is 2 mol / L.

4. The aqueous oil for carbon fiber according to claim 2, characterized in that: In step (2), the reaction temperature is 40-60° C. and the reaction time is 1-5 h; The weight ratio of the silane coupling agent to the activated titanium carbide is 1:

10.

5. The aqueous oil for carbon fiber according to claim 2, characterized in that: In step (3), the reaction temperature is 40-70° C. and the reaction time is 12-24 h; The weight ratio of the product B to the amino-modified polydimethylsiloxane is 1:10-20.

6. The aqueous oil for carbon fiber according to claim 2, characterized in that: The amino-modified polydimethylsiloxane in step (3) is a side-chain epoxy-modified polydimethylsiloxane or a double-end epoxy-modified polydimethylsiloxane.

7. The aqueous oil for carbon fiber according to claim 6, characterized in that: The amino content is 0.05 to 1.5 mmol / g, and the viscosity at 25° C. is 20 to 20,000 mpa·s.

8. The aqueous oil for carbon fiber according to claim 1, characterized in that: The molecular weight of the polyether-modified polydimethylsiloxane is 2000-10000; the molecular weight of the phosphate-modified polysiloxane is 2000-3500.

9. The method for preparing an aqueous oil agent for carbon fiber according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) weighing the raw materials according to the weight parts; (2) The polyether-modified polydimethylsiloxane, the phosphate-modified polysiloxane and the high-temperature resistant auxiliary agent are mixed evenly, and then an emulsifier, an antistatic agent, a defoaming agent and deionized water are added for emulsification to obtain a water-based oil agent for carbon fiber with high heat resistance.

10. The preparation method according to claim 9, characterized in that: The particle size of the aqueous oil agent for carbon fiber is 150-200 nm.

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