Polyurethane structure modified epoxy silicone oil emulsion and preparation method thereof

Abstract

The invention discloses a polyurethane structure modified epoxy silicone oil emulsion and a preparation method thereof. The emulsion comprises the following components in parts by weight: 100 parts of polyurethane structure modified epoxy silicone oil, 30-50 parts of an emulsifier and 5-10 parts of an antistatic agent, and after all the components are uniformly stirred and mixed, the silicone oil emulsion with the particle size distribution of 200-500nm is obtained through a phase inversion emulsification method. The polyurethane structure modified epoxy silicone oil emulsion is used as the oiling agent for producing the carbon fiber precursor, the oiling agent has the characteristics of good bundling property, strong wear resistance and high heat resistance, the protectiveness on the carbon fiber precursor is improved, surface defects caused by friction in production and operation are reduced, meanwhile, high heat resistance protection is provided for the pre-oxidized fiber in the carbonization stage, homogeneous pre-oxidation is realized, and the production efficiency is improved. The mechanical property and broken filament level of the carbon fiber can be effectively improved.

Description

Technical Field

[0001] The invention relates to a polyurethane structure-modified epoxy silicone oil emulsion and a preparation method thereof, and belongs to the technical field of high-performance carbon fiber preparation. Background Art

[0002] In the production process of carbon fiber precursor, the oiling process is a key process in the production process of carbon fiber. The oil agent mainly plays the role of lubricating and protecting the surface of the monofilament in the spinning process, reducing scratches and breakage on the surface of the transported fiber bundle, and can control the oxygen diffusion and heat transfer rate in the pre-oxidation stage through the heat resistance of the oil film, and achieve homogeneous pre-oxidation, which has a crucial impact on the mechanical properties and hair level of the carbon fiber. Chinese patent application CN105297427A discloses a low molecular weight double-terminal epoxy polyether silicone oil that improves the heat resistance of amino-modified silicone oil carbon fiber oil. However, the low molecular weight epoxy polyether silicone oil will cause the heat resistance of the oil agent to decrease. At the same time, there are also problems of poor oil film adhesion and easy desorption in the precursor steam drawing process. Summary of the invention

[0003] The purpose of the present invention is to provide a polyurethane structure-modified epoxy silicone oil emulsion and a preparation method thereof, and the heat resistance and film-forming property of the epoxy silicone oil emulsion are improved by performing polyurethane structure modification on the epoxy silicone oil, thereby improving the bundling property, wear resistance and adhesion of the oil agent to carbon fiber.

[0004] The technical solution for achieving the purpose of the present invention is as follows:

[0005] The polyurethane structure modified epoxy silicone oil emulsion comprises, by weight, 100 parts of polyurethane structure modified epoxy silicone oil, 30-50 parts of emulsifier and 5-10 parts of antistatic agent; the polyurethane structure modified epoxy silicone oil is prepared by the following steps: according to the mass ratio of epoxy silicone oil to isocyanate and catalyst of 100:1-5:0.2-0.5, under the protection of high-purity dry nitrogen, isocyanate and catalyst are added to epoxy silicone oil, and then stirred and mixed at 60±5℃, and then heated to 90±5℃, and continued to react to obtain polyurethane structure modified epoxy silicone oil, wherein the isocyanate is selected from toluene diisocyanate or diphenylmethane diisocyanate.

[0006] Furthermore, the epoxy value of the epoxy silicone oil is 0.20 to 0.60 mmol / g.

[0007] Furthermore, the emulsifier is an emulsifier commonly used in carbon fiber oil, such as fatty alcohol polyoxyethylene ether, castor oil polyoxyethylene ether, etc.

[0008] Furthermore, the antistatic agent is an antistatic agent commonly used in carbon fiber oil, such as quaternary ammonium salt of beef tallow, dodecyltrimethylammonium chloride, etc.

[0009] Further, the catalyst is selected from dibutyltin dilaurate or stannous octoate.

[0010] Furthermore, the stirring and mixing time is 30 to 40 minutes, and the continued reaction time is 60 to 80 minutes.

[0011] The preparation method of the polyurethane structure modified epoxy silicone oil emulsion has the following specific steps: after uniformly mixing the components according to the proportion, adding water and performing phase inversion emulsification to obtain a silicone oil emulsion with a particle size distribution of 200 to 500 nm.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] The present invention adopts polyurethane structure modified epoxy silicone oil to prepare oil emulsion, improves the heat resistance and film-forming property of epoxy silicone oil emulsion, and improves the bundling property, wear resistance and adhesion of oil to carbon fiber. When the polyurethane structure modified epoxy silicone oil emulsion of the present invention is used as a carbon fiber oil agent, it has the characteristics of good bundling property, strong wear resistance and high heat resistance, improves the protection of carbon fiber precursor, reduces the surface defects caused by production and operation friction, and provides high heat resistance protection for pre-oxidized yarn in the carbonization stage, realizes homogeneous pre-oxidation, and can effectively improve the mechanical properties and hair level of carbon fiber. DETAILED DESCRIPTION

[0014] The content and technical solutions of the present invention are further described below in conjunction with specific embodiments, but should not be construed as limiting the present invention. Without departing from the concept of the present invention, simple modifications or replacements made to the method, steps or conditions of the present invention all fall within the scope of the present invention.

[0015] The raw materials and reagents used in the following examples and comparative examples can all be purchased commercially.

[0016] Example 1

[0017] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.20 mmol / g, the isocyanate is toluene diisocyanate, the mass fraction of which is 1, and the catalyst is dibutyltin dilaurate, the mass fraction of which is 0.2. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0018] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by weight of the above-mentioned polyurethane structure-modified epoxy silicone oil, 30 parts by weight of emulsifier fatty alcohol polyoxyethylene ether, and 5 parts by weight of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and then water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 458 nm.

[0019] The evaluation results on the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.85%, the precursor hair grade is 1.5 (divided into 1-5 grades, 1 is the best, 5 is the worst), the oil content of the pre-oxidized yarn is 0.34%, the carbon fiber tensile strength is 5037 MPa, and the carbon fiber hair grade is 1.7 (divided into 1-5 grades, 1 is the best, 5 is the worst).

[0020] Example 2

[0021] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil is 100 parts by weight, and its epoxy value is 0.60 mmol / g, the isocyanate is diphenylmethane diisocyanate, and its mass part is 5, and the catalyst is stannous octoate, and its mass part is 0.5. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, and then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0022] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by weight of the above-mentioned polyurethane structure-modified epoxy silicone oil, 50 parts by weight of emulsifier castor oil polyoxyethylene ether, and 10 parts by weight of antistatic agent dodecyltrimethylammonium chloride are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 221 nm.

[0023] The evaluation results on the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber raw yarn is 0.95%, the raw yarn hair grade is 1.2, the oil content of the pre-oxidized yarn is 0.32%, the carbon fiber tensile strength is 5265MPa, and the carbon fiber hair grade is 1.3.

[0024] Example 3

[0025] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.40 mmol / g, the isocyanate is toluene diisocyanate with a mass fraction of 3, and the catalyst is dibutyltin dilaurate with a mass fraction of 0.3. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0026] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by weight of the above-mentioned polyurethane structure-modified epoxy silicone oil, 35 parts by weight of emulsifier fatty alcohol polyoxyethylene ether, and 7 parts by weight of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 389 nm.

[0027] The evaluation results on the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.90%, the precursor hair grade is 1.4, the oil content of the pre-oxidized yarn is 0.35%, the carbon fiber tensile strength is 5198 MPa, and the carbon fiber hair grade is 1.5.

[0028] Comparative Example 1

[0029] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.20 mmol / g, the isocyanate is toluene diisocyanate, the mass fraction of which is 1, and the catalyst is dibutyltin dilaurate, the mass fraction of which is 0.2. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0030] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by weight of the above-mentioned polyurethane structure-modified epoxy silicone oil, 20 parts by weight of emulsifier fatty alcohol polyoxyethylene ether, and 5 parts by weight of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 655 nm.

[0031] The evaluation results of the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.83%, the precursor hair grade is 1.9, the oil content of the pre-oxidized yarn is 0.38%, the carbon fiber tensile strength is 4870MPa, and the carbon fiber hair grade is 2.3. Compared with Example 1, the reduction in emulsifier content leads to an increase in the emulsion particle size, a deterioration in the uniformity of the precursor oiling, an increase in the precursor and carbon fiber hair, and a decrease in carbonization strength.

[0032] Comparative Example 2

[0033] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.20 mmol / g, the isocyanate is toluene diisocyanate, the mass fraction of which is 1, and the catalyst is dibutyltin dilaurate, the mass fraction of which is 0.2. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0034] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by mass of the above-mentioned polyurethane structure-modified epoxy silicone oil, 60 parts by mass of emulsifier fatty alcohol polyoxyethylene ether, and 15 parts by mass of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 306 nm.

[0035] The evaluation results of the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.93%, the precursor hair grade is 1.5, the oil content of the pre-oxidized yarn is 0.26%, the carbon fiber tensile strength is 4711MPa, and the carbon fiber hair grade is 2.4. Compared with Example 2, the emulsifier content and antistatic agent content in the oil agent are too much, resulting in a decrease in the proportion of heat-resistant polyurethane structure-modified epoxy silicone oil, a significant decrease in the oil content of the pre-oxidized yarn, insufficient heat resistance protection during the carbonization process, resulting in a decrease in carbon fiber strength and an increase in hair.

[0036] Comparative Example 3

[0037] Preparation of conventional epoxy silicone oil emulsion: use 100 parts by mass of epoxy silicone oil with an epoxy value of 0.20 mmol / g, 30 parts by mass of emulsifier fatty alcohol polyoxyethylene ether, and 5 parts by mass of antistatic agent beef tallow quaternary ammonium salt. After stirring and mixing the above components according to the ratio, add water and obtain ordinary epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 334 nm.

[0038] The evaluation results of the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.87%, the precursor hair grade is 2.5, the oil content of the pre-oxidized yarn is 0.23%, the tensile strength of the carbon fiber is 4553MPa, and the carbon fiber hair grade is 3.0. Compared with Example 1, the polyurethane structure modification of the epoxy silicone oil was not performed, and the hair grade of the prepared precursor was significantly increased, indicating that the protective effect of the oil agent on the surface of the precursor was significantly reduced, and the bundling and wear resistance of the fiber were deteriorated; at the same time, the heat resistance of the oil agent was reduced, resulting in a decrease in the oil content of the pre-oxidized yarn, insufficient homogeneous pre-oxidation in the carbonization stage, a decrease in the strength of the carbon fiber, and an increase in the hair grade.

[0039] Comparative Example 4

[0040] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.20 mmol / g, the isocyanate is toluene diisocyanate with a mass fraction of 8, and the catalyst is dibutyltin dilaurate with a mass fraction of 0.8. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0041] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by mass of the above-mentioned polyurethane structure-modified epoxy silicone oil, 30 parts by mass of emulsifier fatty alcohol polyoxyethylene ether, and 5 parts by mass of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 578 nm.

[0042] The evaluation results of the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber precursor is 0.92%, the precursor hair grade is 1.7, the pre-oxidation hair oil content is 0.64%, the carbon fiber tensile strength is 4452MPa, and the carbon fiber hair grade is 2.8. Compared with Example 1, the heat resistance of the oil agent is significantly improved by adding excessive isocyanate and catalyst, resulting in a significant increase in the pre-oxidation oil content. Tar is easily generated in the low-temperature carbonization stage, the fiber monofilaments are hot-wired, defects are generated on the carbon fiber surface, and the performance is reduced.

[0043] Comparative Example 5

[0044] (1) Preparation of polyurethane structure modified epoxy silicone oil: isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, wherein the epoxy silicone oil has a mass fraction of 100 and an epoxy value of 0.20 mmol / g, the isocyanate is hexamethylene diisocyanate with a mass fraction of 1, and the catalyst is dibutyltin dilaurate with a mass fraction of 0.2. The mixture is stirred and mixed at a temperature of 60°C for 30 minutes, then the temperature is raised to 90°C and the reaction is continued for 60 minutes to obtain polyurethane structure modified epoxy silicone oil.

[0045] (2) Preparation of polyurethane structure-modified epoxy silicone oil emulsion: 100 parts by weight of the above-mentioned polyurethane structure-modified epoxy silicone oil, 30 parts by weight of emulsifier fatty alcohol polyoxyethylene ether, and 5 parts by weight of antistatic agent beef tallow quaternary ammonium salt are mixed according to the ratio, and water is added to obtain polyurethane structure-modified epoxy silicone oil emulsion by phase inversion emulsification method, and the particle size is 387 nm.

[0046] The evaluation results of the production line using the prepared oil agent are shown in Table 1. The oil content of the carbon fiber raw yarn is 0.82%, the raw yarn hair grade is 1.6, the pre-oxidation yarn oil content is 0.29%, the carbon fiber tensile strength is 4920MPa, and the carbon fiber hair grade is 2.1. Compared with Example 1, the isocyanate used is hexamethylene diisocyanate, and the polyurethane structure-modified epoxy silicone oil obtained lacks a benzene ring structure, and the heat resistance of the oil agent decreases. The protective effect of the oil agent on the carbon fiber is weakened during the pre-oxidation process, and the hair increases while the strength decreases.

[0047]

[0048] In summary, the present invention uses polyurethane structure modified epoxy silicone oil to prepare emulsion, which improves the heat resistance and film-forming property of epoxy silicone oil emulsion. The modified epoxy silicone oil emulsion of the present invention is used as an oil agent for the production of carbon fiber precursor, and has the characteristics of good bundling, strong wear resistance and high heat resistance, which improves the protection of carbon fiber precursor and can reduce the surface defects caused by production and operation friction; at the same time, the carbonization stage provides high heat resistance protection for the pre-oxidized yarn, realizes homogeneous pre-oxidation, and can effectively improve the mechanical properties and hair level of carbon fiber.

Claims

1. Polyurethane structure modified epoxy silicone oil emulsion, characterized in that, The invention comprises 100 parts of polyurethane structure modified epoxy silicone oil, 30-50 parts of emulsifier and 5-10 parts of antistatic agent by weight. The polyurethane structure modified epoxy silicone oil is prepared by the following steps: according to the mass ratio of epoxy silicone oil to isocyanate and catalyst of 100:1-5:0.2-0.5, isocyanate and catalyst are added to epoxy silicone oil under the protection of high-purity dry nitrogen, and then stirred and mixed at 60±5°C, and then heated to 90±5°C, and continued to react to obtain polyurethane structure modified epoxy silicone oil, wherein the isocyanate is selected from toluene diisocyanate or diphenylmethane diisocyanate.

2. The polyurethane structure-modified epoxy silicone oil emulsion according to claim 1, characterized in that: The epoxy value of epoxy silicone oil is 0.20~0.60 mmol / g.

3. The polyurethane structure-modified epoxy silicone oil emulsion according to claim 1, characterized in that: The emulsifier is fatty alcohol polyoxyethylene ether or castor oil polyoxyethylene ether.

4. The polyurethane structure-modified epoxy silicone oil emulsion according to claim 1, characterized in that: The antistatic agent is quaternary ammonium salt of tallow or dodecyltrimethylammonium chloride.

5. The polyurethane structure-modified epoxy silicone oil emulsion according to claim 1, characterized in that: The catalyst is dibutyltin dilaurate or stannous octoate.

6. The polyurethane structure-modified epoxy silicone oil emulsion according to claim 1, characterized in that: The stirring and mixing time is 30~40min, and the continued reaction time is 60~80min.

7. The method for preparing the polyurethane structure-modified epoxy silicone oil emulsion according to any one of claims 1 to 6, characterized in that: The specific steps are as follows: After the components are uniformly mixed according to the ratio, water is added to obtain a silicone oil emulsion with a particle size distribution of 200~500nm through a phase inversion emulsification method.

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