Water-based environment-friendly gum dipping system and process technology for preparing carbon fiber framework material by using water-based environment-friendly gum dipping system

Abstract

The invention relates to the technical field of continuous fiber composite material preparation, and discloses a water-based environment-friendly impregnation system and a process technology for preparing a carbon fiber framework material by using the same. The water-based environment-friendly impregnation system is prepared from the following raw materials: deionized water, vinyl resin, cumyl hydroperoxide, bisphenol A epoxy resin and 1, 2-cyclohexanediamine. The impregnation system is adopted to perform impregnation treatment on continuous carbon fiber precursors, the continuous carbon fiber precursors are twisted into carbon fiber tows after being dried and shaped, then the carbon fiber tows are soaked in RFL impregnation liquid for the second time, and the continuous carbon fiber framework material product is obtained after drying, curing crosslinking and shaping. According to the preparation process, continuous carbon fibers are firstly soaked and dried, then twisted together and then subjected to secondary soaking, the infiltration rate of carbon fiber tows can be increased, dispersed carbon fiber filaments can be bonded and twisted into an organic whole, and the bearing capacity of the carbon fiber framework material is improved.

Description

Technical Field

[0001] The invention relates to the technical field of continuous fiber composite material preparation, and in particular to an aqueous environmentally friendly dipping system and a process technology for preparing a carbon fiber skeleton material using the same. Background Art

[0002] Carbon fiber has a broad market prospect in the field of high-performance synchronous belts, automobile tires, aviation tires and other rubber products due to its high specific strength and specific modulus, good thermal conductivity and low elongation at break. However, the surface of carbon fiber is smooth and lacks functional groups that interact with the rubber matrix. In addition, the huge difference in chemical properties and modulus between polar fiber and non-polar rubber results in poor adhesion between carbon fiber and rubber, and stress concentration will occur at the junction of carbon fiber and rubber, which seriously affects the performance of carbon fiber reinforced rubber products. In order to overcome the huge difference between polar fiber and non-polar rubber, carbon fiber needs to be dipped in glue before use in industry.

[0003] At present, the impregnation liquid for industrial processing of carbon fiber is mostly RFL, but since the RFL impregnation liquid lacks substances that can be fused with the resin on the surface of the carbon fiber raw yarn, the wettability of the carbon fiber bundle in the RFL impregnation liquid is low; and the effective substances in RFL are mostly aromatic compounds, the products after the cross-linking reaction are highly rigid, and the prepared carbon fiber bundles are relatively hard, making the subsequent twisting treatment more difficult and it is difficult to achieve effective twisting of the carbon fiber bundles; and after RFL is cured, the hard glue film formed on the surface of the carbon fiber will cause the carbon fiber to break during the twisting process, affecting the load-bearing capacity of the carbon fiber bundle. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an aqueous environmentally friendly dipping system and a process for preparing a carbon fiber skeleton material using the same.

[0005] In order to achieve the above-mentioned purpose, the technical scheme of the present invention is: an aqueous environmentally friendly dipping system, which includes the following raw materials by weight: 40 to 60 parts of deionized water, 25 to 40 parts of vinyl resin, 5 to 10 parts of isopropylbenzene hydroperoxide, 15 to 20 parts of bisphenol A epoxy resin and 5 to 10 parts of 1,2-cyclohexanediamine.

[0006] Furthermore, the vinyl resin is a water-based vinyl resin.

[0007] Another technical solution of the present invention is: a process technology for preparing carbon fiber skeleton materials with the aqueous environmentally friendly dipping system, wherein the continuous carbon fiber precursor is once impregnated with the aqueous environmentally friendly dipping system for 120 seconds, then dried at 190°C for 90 seconds, heated to 200°C after drying for activation reaction for 90 seconds, and then heat-set at 200°C for 120 seconds; then the fixed carbon fiber tow is twisted; the twisted carbon fiber tow is secondarily impregnated with RFL dipping solution for 120 seconds, dried at 200°C for 90 seconds, heated to 230°C after drying for activation reaction for 90 seconds, and then enters the drawing machine for heat setting at 200°C for 120 seconds, and then stretched to obtain a continuous carbon fiber skeleton material.

[0008] Furthermore, the twisting treatment method is: twisting the carbon fiber tow that has been once impregnated and shaped in the S direction or Z direction, with a twist of 30 to 300 twists / m.

[0009] Furthermore, the drawing tension is 800g / root and the vehicle speed is 3 meters / minute.

[0010] Furthermore, the RFL dipping solution preparation method is: 2.8Kg of resorcinol-formaldehyde resin with a solid content of 75% is mixed with 16.5Kg of softened water and 2.2Kg of ammonia water with a mass concentration of 25% to obtain solution A; 42Kg of butadiene latex with a solid content of 40% is mixed with 14Kg of softened water to obtain solution B; solution A and solution B are mixed and stirred, and after standing for 24 hours, 22.5Kg of adhesive RP is added, and the RFL dipping solution is obtained after mixing and stirring.

[0011] The beneficial effects of the present invention are as follows: the continuous carbon fiber is treated with the aqueous environmentally friendly impregnation solution of the present invention, wherein the vinyl resin and the bisphenol A epoxy resin can be mutually dissolved with the epoxy resin on the surface of the carbon fiber tow, thereby improving the wettability of the impregnation solution and the carbon fiber; the vinyl resin and the epoxy resin can react with cross-linking agents such as isopropyl hydroperoxide and 1,2-cyclohexanediamine, respectively, to cross-link and cure on the surface of the carbon fiber to form a layer of high-performance adhesive film with moderate hardness. The adhesive film can not only protect the fiber and prevent it from being worn by mechanical parts during travel, but also produce large-angle bending, so that the carbon fiber tow after the first dip can be easily twisted, reducing the fiber breakage rate of the carbon fiber during the twisting process, thereby improving the bearing capacity of the carbon fiber; the epoxy resin and 1,2-cyclohexanediamine on the surface of the carbon fiber after the first dip can also react with the phenolic resin and butyl latex in the second dip RFL respectively, so that the adhesive films on the fiber surface of the first dip and the second dip become an organic whole, thereby improving the adhesion between the carbon fiber skeleton material and the rubber; the preparation process of first dipping the continuous carbon fiber, drying it, twisting it together, and then dipping it twice can not only improve the impregnation rate of the carbon fiber tow, but also can bond and twist the dispersed fibers into an organic whole, thereby improving the bearing capacity (i.e., breaking strength) of the carbon fiber skeleton material. DETAILED DESCRIPTION

[0012] The present invention is described in detail below with reference to specific embodiments, but the protection scope is not limited thereto.

[0013] The bisphenol A epoxy resin used in the present invention is bisphenol A epoxy resin E51, produced by Japan Nagase Industry Co., Ltd.

[0014] The manufacturer of 1,2-cyclohexanediamine is DuPont (China) Co., Ltd.

[0015] The manufacturer of cumene hydroperoxide is Sigma-Aldrich (Shanghai) Co., Ltd.

[0016] The molecular weight of the water-based vinyl resin is 12,000, and the manufacturer is Shanghai Fuchen Chemical Co., Ltd.;

[0017] The manufacturer of polymeric p-diphenylmethane diisocyanate (pMDI) is Wanhua Chemical Group Co., Ltd.

[0018] The adhesive RP manufacturer is Yixing Liangxing New Materials Co., Ltd.

[0019] Example 1

[0020] A water-based environmentally friendly dipping system is prepared by mixing and stirring 40g of deionized water, 25g of water-based vinyl resin, 15g of bisphenol A epoxy resin E51, 5g of cumene hydroperoxide and 5g of 1,2-cyclohexanediamine to obtain the water-based environmentally friendly dipping system.

[0021] Example 2

[0022] A water-based environmentally friendly dipping system is prepared by mixing and stirring 50g of deionized water, 35g of water-based vinyl resin, 20g of bisphenol A epoxy resin E51, 10g of cumene hydroperoxide and 10g of 1,2-cyclohexanediamine to obtain the water-based environmentally friendly dipping system.

[0023] Example 3

[0024] A water-based environmentally friendly dipping system is prepared by mixing and stirring 60g of deionized water, 40g of water-based vinyl resin, 20g of bisphenol A epoxy resin E51, 10g of cumene hydroperoxide and 10g of 1,2-cyclohexanediamine to obtain the water-based environmentally friendly dipping system.

[0025] Example 4

[0026] A process for a high-performance continuous carbon fiber skeleton material: 12K and T800 continuous carbon fibers are immersed in an immersion tank for 120 seconds, wherein the immersion tank is filled with the dipping system prepared in Example 1, and then dried at 190°C for 90 seconds, and after drying, the temperature is raised to 200°C for activation reaction for 90 seconds, and then heat-set at 200°C for 120 seconds; then the carbon fiber tow after the immersion setting is pulled to a twisting machine, and the carbon fiber is twisted to be twisted into a carbon fiber rope with a twist of 100. The twisted carbon fiber is then immersed in two dipping tanks for 120 seconds, in which the RFL dipping solution is contained, and dried at 200°C for 90 seconds. After drying, the temperature is raised to 230°C for activation reaction for 90 seconds, and then enters the drawing machine for heat setting at 200°C for 120 seconds, and then drawn. The drawing tension of the drawing machine is 800g / root, and the speed is 3 meters / minute. The high-performance continuous carbon fiber skeleton material product is obtained, and then it is rolled up and parked for 12 hours for performance testing.

[0027] The preparation method of the RFL dipping solution is as follows: 2.8 kg of resorcinol-formaldehyde resin with a solid content of 75% is mixed with 16.5 kg of softened water and 2.2 kg of ammonia water with a mass concentration of 25% to obtain a solution A; 42 kg of butadiene latex with a solid content of 40% is mixed with 14 kg of softened water to obtain a solution B; the solution A and the solution B are mixed and stirred, and after standing for 24 hours, 22.5 kg of adhesive RP is added, and the RFL dipping solution is obtained after mixing and stirring.

[0028] Comparative Example 1

[0029] A method for preparing a continuous carbon fiber skeleton material, which is different from Example 4 in that: a dipping tank is filled with pMDI and an epoxy resin aqueous solution, and the pMDI and epoxy resin aqueous solution are prepared by adding 5g pMDI and 2g bisphenol A epoxy resin E51 to 93g deionized water, and dissolving them to obtain the pMDI and epoxy resin aqueous solution.

[0030] Performance Testing

[0031] The properties of the continuous carbon fiber skeleton materials prepared in Example 4 and Comparative Example 1 were tested according to GB / T 33099-2016. The results are shown in Table 1.

[0032] Table 1

[0033]

[0034]

[0035] As can be seen from Table 1, for 12K and T800 continuous carbon fibers, the hardness of the skeleton material prepared by the dipping system of the present invention is 137 gf, which is much lower than the hardness (452) of the skeleton material prepared in Comparative Example 1, and the fracture strength and interface adhesion of the fiber skeleton material prepared by the present invention are 1860 N and 517 N, respectively, which are significantly higher than the fracture strength (1493) and interface adhesion (370) of the fiber skeleton material prepared in Comparative Example 1. From the test results, it can be seen that the water-based environmentally friendly dipping system of the present invention can prepare a soft and excellent continuous carbon fiber skeleton material.

[0036] The above-described embodiments are only preferred solutions of the present invention and are not intended to limit the present invention in any form. Other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims

1. A water-based environmentally friendly dipping system, characterized in that: The raw materials include the following in parts by weight: 40-60 parts of deionized water, 25-40 parts of vinyl resin, 5-10 parts of cumene hydroperoxide, 15-20 parts of bisphenol A epoxy resin and 5-10 parts of 1,2-cyclohexanediamine.

2. The water-based environmentally friendly dipping system according to claim 1, characterized in that: The vinyl resin is a water-based vinyl resin.

3. A process for preparing carbon fiber skeleton material by using the water-based environmentally friendly dipping system according to claim 1, characterized in that: The continuous carbon fiber precursor is immersed in the aqueous environmentally friendly dipping system for 120 seconds, then dried at 190°C for 90 seconds, heated to 200°C for activation reaction for 90 seconds after drying, and then heat-set at 200°C for 120 seconds; then the set carbon fiber tow is twisted; the twisted carbon fiber tow is immersed in the RFL dipping solution for a second time for 120 seconds, dried at 200°C for 90 seconds, heated to 230°C for activation reaction for 90 seconds after drying, and then enters the drawing machine for heat setting at 200°C for 120 seconds, and then stretched to obtain a continuous carbon fiber skeleton material.

4. The process technology according to claim 3, characterized in that: The twisting treatment method comprises twisting the carbon fiber tow which has been once impregnated and shaped in the S direction or the Z direction, and the twist degree is 30 to 300 twists / meter.

5. The process technology according to claim 3, characterized in that: The drawing tension is 800 g / piece and the vehicle speed is 3 m / min.

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