Propenyl modified sizing agent as well as preparation method and application method thereof

Abstract

The invention relates to a propenyl modified sizing agent as well as a preparation method and an application method thereof, and belongs to the technical field of sizing agents. The preparation method of the allyl modified sizing agent comprises the following steps: (1) mixing epoxy resin and allyl polyethylene glycol, introducing nitrogen, and mixing at 70-90 DEG C for 20-40 minutes to obtain a mixed material; (2) adding a catalyst into the mixed material, mixing, mixing and catalyzing epoxy resin and allyl polyethylene glycol at 100-120 DEG C to react for 3-5 hours, cooling to 70-90 DEG C after the reaction, adding a cross-linking agent, and mixing for 20-40 minutes to obtain a sizing agent main material; and (3) mixing the sizing agent main material with epoxy resin, and carrying out phase inversion emulsification to obtain the allyl modified sizing agent. The interface bonding property and the stability between the carbon fiber and the vinyl resin can be effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of sizing agents, and in particular to an propylene-modified sizing agent and a preparation method and an application method thereof. Background Art

[0002] After surface treatment, carbon fiber will contain carboxyl and hydroxyl groups on its surface, but lacks active groups that can react chemically with vinyl resin, so the interface performance between carbon fiber and vinyl resin is not good. By introducing a sizing agent transition layer between carbon fiber and vinyl resin, it can not only chemically bond on the carbon fiber surface, but also enhance the interaction with the vinyl resin matrix, thereby improving the interface performance between carbon fiber and vinyl resin.

[0003] However, the epoxy resin sizing agents currently available on the market have poor effects on improving the interface properties between carbon fiber and vinyl resin matrix after sizing, which in turn affects the actual production and application of composite materials. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the embodiments of the present application includes providing an propylene-based modified sizing agent and a preparation method and application method thereof, which can effectively improve the interface performance between carbon fiber and vinyl resin matrix.

[0005] In a first aspect, the present application provides a method for preparing a propylene-based modified sizing agent, comprising:

[0006] (1) mixing epoxy resin and allyl polyethylene glycol, introducing nitrogen, and mixing at 70-90° C. for 20-40 minutes to obtain a mixed material;

[0007] (2) adding a catalyst to the mixture, mixing and catalyzing the epoxy resin and allyl polyethylene glycol at 100-120° C. for 3-5 hours, cooling to 70-90° C. after the reaction, adding a crosslinking agent and mixing for 20-40 minutes to obtain a sizing agent main material;

[0008] (3) The main material of the sizing agent is mixed with the epoxy resin, and phase inversion emulsification is performed to obtain an acrylic modified sizing agent.

[0009] The present application uses allyl polyethylene glycol to react with epoxy resin under the action of a catalyst, so that a large number of hydroxyl groups are directly grafted to the epoxy resin, thereby improving the hydrophilicity, emulsification and wettability, and being able to be more evenly distributed on the surface of the carbon fiber, and providing better consistency in the protection of the single fiber of the carbon fiber; at the same time, allyl polyethylene glycol will provide double bonds, which can react and cross-link with the vinyl resin, thereby effectively increasing the interface bonding and stability between the carbon fiber and the vinyl resin.

[0010] In some embodiments of the present application, the mass ratio of epoxy resin to allyl polyethylene glycol is 1:2-4.

[0011] The present application uses epoxy resin and allyl polyethylene glycol in a suitable mass ratio to react, and can efficiently graft a large number of hydroxyl groups directly to the epoxy resin, thereby effectively improving the hydrophilicity, emulsification and wettability of the sizing agent.

[0012] In some embodiments of the present application, the mass ratio of the catalyst to the epoxy resin is 1:18-22.

[0013] The present application can efficiently catalyze the reaction between epoxy resin and allyl polyethylene glycol by using a catalyst in a suitable mass ratio with the epoxy resin.

[0014] In some embodiments of the present application, the mass ratio of the cross-linking agent to the epoxy resin is 1:2-4.

[0015] The present application adopts a cross-linking agent in an appropriate mass ratio with the epoxy resin, so that the epoxy resin modified by the allyl polyethylene glycol can be efficiently cross-linked to form a sizing agent main material, so that the sizing agent main material can ensure an appropriate viscosity.

[0016] In some embodiments of the present application, the epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

[0017] The present application adopts the above-mentioned epoxy resin, which can react with allyl polyethylene glycol under the action of a catalyst, so that a large number of hydroxyl groups are directly grafted to the epoxy resin.

[0018] In some embodiments of the present application, the catalyst includes at least one of tetrabutylammonium bromide, tetrabutylammonium chloride, and benzyltriethylammonium chloride.

[0019] The present application adopts the above catalyst to catalyze the reaction of epoxy resin and allyl polyethylene glycol under certain conditions.

[0020] In some embodiments of the present application, the cross-linking agent includes styrene.

[0021] The present application adopts the above cross-linking agent to efficiently cross-link the epoxy resin modified by allyl polyethylene glycol to form the main material of the sizing agent.

[0022] In some embodiments of the present application, water is also added in step (4), and the mass ratio of epoxy resin, sizing agent main material and water is 1:1-2:2-3.

[0023] The present application adopts epoxy resin, sizing agent main material and water in a suitable mass ratio to efficiently carry out phase inversion emulsification to obtain acryl-modified sizing agent.

[0024] In a second aspect, an embodiment of the present application provides an propylene-modified sizing agent prepared by the preparation method provided in the first aspect.

[0025] The propylene-based modified sizing agent prepared by the above-mentioned preparation method in the present application has high hydrophilicity, emulsification and wettability, and contains double bonds. When used on the surface of carbon fiber, it can effectively increase the interface bonding and stability between carbon fiber and vinyl resin.

[0026] In a third aspect, the present application embodiment provides an application method of the propylene-based modified sizing agent provided in the second aspect, comprising:

[0027] (1) dipping the carbon fiber in an acrylic modified sizing agent, and drying the sizing agent after sizing;

[0028] (2) mixing a resin and a curing agent to form a resin mixture, impregnating the sized carbon fiber with the resin mixture, and curing and molding the mixture to obtain a carbon fiber composite material;

[0029] Among them, the resin includes vinyl resin.

[0030] The present application forms a vinyl resin carbon fiber composite material by using the above-mentioned sizing agent between carbon fiber and vinyl resin. Since the above-mentioned sizing agent can effectively improve the interface bonding and stability between carbon fiber and vinyl resin matrix, the obtained vinyl resin carbon fiber composite material has higher strength performance. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0032] The present application embodiment provides a method for preparing an propylene-based modified sizing agent, comprising:

[0033] (1) mixing epoxy resin and allyl polyethylene glycol, introducing nitrogen, and mixing at 70-90° C. for 20-40 minutes to obtain a mixed material;

[0034] (2) adding a catalyst to the mixture, mixing and catalyzing the epoxy resin and allyl polyethylene glycol at 100-120° C. for 3-5 hours, cooling to 70-90° C. after the reaction, adding a crosslinking agent and mixing for 20-40 minutes to obtain a sizing agent main material;

[0035] (3) The main material of the sizing agent is mixed with the epoxy resin, and phase inversion emulsification is performed to obtain an acrylic modified sizing agent.

[0036] Allyl polyethylene glycol is reacted with epoxy resin under the action of a catalyst to modify the epoxy resin with allyl polyethylene glycol, and a large number of hydroxyl groups are directly grafted onto the epoxy resin to improve the hydrophilicity, emulsification and wettability of the epoxy resin, so that it can be more evenly distributed on the surface of carbon fiber, and the consistency of the protection of the single fiber of the carbon fiber is better, and the defect sites are reduced; at the same time, allyl polyethylene glycol will provide double bonds, and the double bonds can react and cross-link with vinyl resin; the prepared sizing agent has high hydrophilicity, emulsification and wettability, and contains more double bonds that can react and cross-link with vinyl resin, thereby effectively increasing the interface bonding and stability between the carbon fiber and the vinyl resin.

[0037] In some embodiments of the present application, the mass ratio of epoxy resin to allyl polyethylene glycol is 1:2-4. As an example, the mass ratio of epoxy resin to allyl polyethylene glycol can be, but is not limited to, 1:2, 1:2.5, 1:3, 1:3.5, 1:4. By reacting epoxy resin and allyl polyethylene glycol in a suitable mass ratio, a large number of hydroxyl groups can be directly grafted to the epoxy resin more efficiently, thereby effectively improving the hydrophilicity, emulsification and wettability of the sizing agent.

[0038] In some embodiments of the present application, the mass ratio of the catalyst to the epoxy resin is 1:18-22. As an example, the mass ratio of the catalyst to the epoxy resin can be, but is not limited to, 1:18, 1:19, 1:20, 1:21, 1:22. The use of a catalyst having a suitable mass ratio to the epoxy resin can efficiently catalyze the reaction of the epoxy resin and the allyl polyethylene glycol.

[0039] In some embodiments of the present application, the mass ratio of the crosslinking agent to the epoxy resin is 1:2-4. As an example, the mass ratio of the crosslinking agent to the epoxy resin can be, but is not limited to, 1:2, 1:2.5, 1:3, 1:3.5, 1:4. By using a crosslinking agent with a suitable mass ratio to the epoxy resin, the epoxy resin modified by the allyl polyethylene glycol can be efficiently crosslinked to form the main material of the sizing agent.

[0040] In some embodiments of the present application, the epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin. As an example, bisphenol A epoxy resin can be but not limited to E44, E55, E51, E35, E20. Bisphenol F epoxy resin can be but not limited to Flanders F3, Flanders F8, Natural F200, Natural F500, Natural F1000. The above-mentioned epoxy resins can be reacted with allyl polyethylene glycol under the action of a catalyst to directly graft a large number of hydroxyl groups to the epoxy resin.

[0041] In some embodiments of the present application, the catalyst includes at least one of tetrabutylammonium bromide, tetrabutylammonium chloride, and benzyltriethylammonium chloride. The above catalysts can catalyze the reaction of epoxy resin and allyl polyethylene glycol under certain conditions.

[0042] In some embodiments of the present application, the crosslinking agent includes styrene. The above crosslinking agents can effectively crosslink the epoxy resin modified by allyl polyethylene glycol to form the main material of the sizing agent.

[0043] In some embodiments of the present application, water is also added in step (4), and the mass ratio of epoxy resin, sizing agent main material and water is 1:1-2:2-3. With the appropriate mass ratio of epoxy resin, sizing agent main material and water, phase inversion emulsification can be efficiently performed to obtain acryl modified sizing agent.

[0044] The embodiment of the present application provides an propylene-modified sizing agent prepared by the above-mentioned preparation method.

[0045] The propylene-modified sizing agent prepared by the above-mentioned preparation method has high hydrophilicity, emulsification and wettability, and contains double bonds. When used on the surface of carbon fiber, it can effectively increase the interface bonding and stability between carbon fiber and vinyl resin.

[0046] The present application embodiment provides an application method of the above-mentioned acrylic modified sizing agent, comprising:

[0047] (1) dipping the carbon fiber in an acrylic modified sizing agent, and drying the sizing agent after sizing;

[0048] (2) mixing a resin and a curing agent to form a resin mixture, impregnating the sized carbon fiber with the resin mixture, and curing and molding the mixture to obtain a carbon fiber composite material;

[0049] Among them, the resin includes vinyl resin.

[0050] The above-mentioned sizing agent is applied between carbon fiber and vinyl resin to form a vinyl resin carbon fiber composite material. Since the above-mentioned sizing agent can effectively improve the interface bonding and stability between carbon fiber and vinyl resin matrix, the obtained vinyl resin carbon fiber composite material has higher strength performance.

[0051] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0052] Example 1

[0053] This embodiment provides a method for preparing an propylene-based modified sizing agent, comprising:

[0054] (1) 100 g of bisphenol A epoxy resin and 200 g of allyl polyethylene glycol were added to a three-necked flask, mixed, nitrogen was introduced, the temperature was raised to 80° C., and the mixture was stirred at 400 r / min for 30 min to obtain a mixed material;

[0055] (2) Add 5 g of tetrabutylammonium bromide to the mixture, mix well, heat to 110° C., stir and mix at 400 r / min to catalyze the reaction of epoxy resin and allyl polyethylene glycol for 4 h, cool naturally to 80° C. after the reaction, add 50 g of styrene, stir and mix at 400 r / min for 30 min, and obtain the main material of the sizing agent;

[0056] (3) The main material of the sizing agent is mixed with bisphenol F epoxy resin and deionized water in a mass ratio of 2:1:3, and phase inversion emulsification is performed to obtain an propylene-modified sizing agent.

[0057] Example 2

[0058] This embodiment provides a method for preparing an propylene-based modified sizing agent, comprising:

[0059] (1) 100 g of bisphenol A epoxy resin and 200 g of allyl polyethylene glycol were added to a three-necked flask, mixed, nitrogen was introduced, the temperature was raised to 80° C., and the mixture was stirred at 400 r / min for 30 min to obtain a mixed material;

[0060] (2) Add 5 g of tetrabutylammonium chloride to the mixture, mix well, heat to 110° C., stir and mix at 400 r / min to catalyze the reaction of epoxy resin and allyl polyethylene glycol for 4 h, cool naturally to 80° C. after the reaction, add 50 g of styrene, stir and mix at 400 r / min for 30 min, and obtain the main material of the sizing agent;

[0061] (3) The main material of the sizing agent is mixed with bisphenol F epoxy resin and deionized water in a mass ratio of 2:1:3, and phase inversion emulsification is performed to obtain an propylene-modified sizing agent.

[0062] Example 3

[0063] This embodiment provides a method for preparing an propylene-based modified sizing agent, comprising:

[0064] (1) 100 g of bisphenol A epoxy resin and 200 g of allyl polyethylene glycol were added to a three-necked flask, mixed, nitrogen was introduced, the temperature was raised to 80° C., and the mixture was stirred at 400 r / min for 30 min to obtain a mixed material;

[0065] (2) Add 5 g of benzyltriethylammonium chloride to the mixture, mix well, heat to 110° C., stir and mix at 400 r / min to catalyze the reaction of epoxy resin and allyl polyethylene glycol for 4 h, cool naturally to 80° C. after the reaction, add 50 g of styrene, stir and mix at 400 r / min for 30 min, and obtain the main material of the sizing agent;

[0066] (3) The main material of the sizing agent is mixed with bisphenol F epoxy resin and deionized water in a mass ratio of 2:1:3, and phase inversion emulsification is performed to obtain an propylene-modified sizing agent.

[0067] Comparative Example 1

[0068] This comparative example provides a method for preparing an propylene-modified sizing agent, which differs from Example 1 in that allyl polyethylene glycol is replaced by acrylic acid.

[0069] Comparative Example 2

[0070] This comparative example provides a method for preparing a sizing agent, comprising:

[0071] (1) Add 100 g of bisphenol A epoxy resin and 50 g of diphenylmethane diisocyanate into a three-necked flask, heat to 85° C., and react at 200 r / min for 3 h;

[0072] (2) adding 80 g of allyl polyethylene glycol and continuing the reaction at 200 r / min for 2 h to obtain the main material of the sizing agent;

[0073] (3) The main material of the sizing agent is mixed with bisphenol F epoxy resin and deionized water in a mass ratio of 2:1:3, and phase inversion emulsification is performed to obtain a sizing agent.

[0074] The preparation methods of Examples 1-3 and Comparative Examples 1-2 are shown in Table 1.

[0075] Table 1 Preparation methods of Examples 1-3 and Comparative Examples 1-2

[0076]

[0077] Note: “ / ” in Table 1 means that the component is not included.

[0078] Test Example 1

[0079] In this test example, the sizing agents provided in Examples 1-3 and Comparative Examples 1-2 were diluted to a content of 1.0%, and the particle size and stability of the sizing agent emulsion were tested; and the sizing agents were attached to T700 grade 12K carbon fiber tows by an infiltration method, dried at 200°C, and then the sizing carbon fiber hair quantity and fiber hardness were tested. The results are shown in Table 1.

[0080] Wherein, (1) the particle size of the sizing agent emulsion is tested using a laser particle size analyzer Microtrac S3500, and the emulsion sample is automatically diluted to a suitable concentration for testing.

[0081] (2) The sizing agent emulsion is allowed to stand for 1 month and the emulsion stability is observed. An emulsion without stratification and without precipitation at the bottom is excellent in stability, an emulsion without stratification but with precipitation at the bottom is good in stability, and an emulsion with stratification and precipitation at the bottom is poor in stability.

[0082] (3) Test the hardness and fuzz quantification of sized carbon fiber according to the hardness and fuzz quantification methods in Carbon Fiber and Graphite Fiber.

[0083] Table 1 Sizing agent properties

[0084] sample Emulsion particle size (nm) Emulsion stability Carbon fiber hardness (cm) Wool quantity (mg / 50m) Example 1 211 excellent 10 3.2 Example 2 244 excellent 9 2.9 Example 3 231 excellent 11 3.3 Comparative Example 1 683 Difference 13 8.2 Comparative Example 2 749 Difference 15 9.5

[0085] From the results in Table 1, it can be seen that the sizing agent emulsions prepared in Examples 1-3 have suitable particle sizes and excellent stability; the carbon fibers impregnated with the sizing agents provided in Examples 1-3 have low hardness and less fuzz. This indicates that the propylene-modified sizing agent emulsions prepared by the preparation method of the propylene-modified sizing agent provided in this application have high hydrophilicity, emulsification and wettability, can be more evenly distributed on the surface of carbon fibers, reduce defect sites, and have better consistency in protecting the single fibers of carbon fibers. It can have better compatibility with vinyl resins, thereby facilitating the improvement of the interfacial bonding strength between carbon fibers and vinyl resin matrixes.

[0086] Implementation Group 1

[0087] This implementation group provides an application method of an propylene-based modified sizing agent, comprising:

[0088] (1) The carbon fibers were respectively impregnated with the acrylic modified sizing agents provided in 1-3 and Comparative Example 1-2 (see Table 1), and then dried after sizing;

[0089] (2) A vinyl resin (Aliance 430LV) and a curing agent (Nouryon LPT-IN) are mixed to form a vinyl resin mixture, and each sized carbon fiber is impregnated with the vinyl resin mixture, and then cured and formed to obtain a carbon fiber composite material.

[0090] Test Example 2

[0091] In this test example, the interlaminar shear strength between the sized carbon fiber and the vinyl resin matrix was tested for each carbon fiber composite material provided in implementation group 1 according to GB / T 30969. The results are shown in Table 2.

[0092] Table 2 Carbon fiber composite material properties

[0093] sample Resin Sizing agent Interlaminar shear strength(Mpa) 1 Vinyl resin Example 1 96 2 Vinyl resin Example 2 97 3 Vinyl resin Example 3 94 4 Vinyl resin Comparative Example 1 82 5 Vinyl resin Comparative Example 2 85

[0094] From the results in Table 2, it can be seen that the propylene-based modified sizing agent prepared in Examples 1-3 is applied to the vinyl resin carbon fiber composite material formed between the carbon fiber and the vinyl resin matrix, and its layer shear strength is relatively high. This indicates that the propylene-based modified sizing agent prepared by the preparation method of the propylene-based modified sizing agent provided in the present application can effectively improve the interfacial bonding strength between the carbon fiber and the vinyl resin matrix.

[0095] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

Claims

1. A method for preparing an propylene-modified sizing agent, characterized in that: include: (1) mixing epoxy resin and allyl polyethylene glycol, introducing nitrogen, and mixing at 70-90° C. for 20-40 minutes to obtain a mixed material; (2) adding a catalyst to the mixture, mixing and catalyzing the epoxy resin and the allyl polyethylene glycol at 100-120° C. for 3-5 hours, cooling to 70-90° C. after the reaction, adding a crosslinking agent and mixing for 20-40 minutes to obtain a sizing agent main material; (3) The main ingredient of the sizing agent is mixed with an epoxy resin, and phase inversion emulsification is performed to obtain the acrylic modified sizing agent.

2. The preparation method according to claim 1, characterized in that: The mass ratio of the epoxy resin to the allyl polyethylene glycol is 1:2-4.

3. The preparation method according to claim 1, characterized in that: The mass ratio of the catalyst to the epoxy resin is 1:18-22.

4. The preparation method according to claim 1, characterized in that: The mass ratio of the cross-linking agent to the epoxy resin is 1:2-4.

5. The preparation method according to claim 1, characterized in that: The epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

6. The preparation method according to claim 1, characterized in that: The catalyst includes at least one of tetrabutylammonium bromide, tetrabutylammonium chloride and benzyltriethylammonium chloride.

7. The preparation method according to claim 1, characterized in that: The cross-linking agent includes styrene.

8. The preparation method according to claim 1, characterized in that: Water is also added in the step (4), and the mass ratio of the epoxy resin, the main material of the sizing agent and the water is 1:1-2:2-3.

9. An propylene-modified sizing agent prepared by the preparation method according to any one of claims 1 to 8.

10. A method for applying the acrylic modified sizing agent according to claim 9, characterized in that: include: (1) dipping the carbon fiber into the acrylic modified sizing agent, and drying after sizing; (2) mixing a resin and a curing agent to form a resin mixture, impregnating the sized carbon fiber with the resin mixture, and curing and molding the carbon fiber to obtain a carbon fiber composite material; Wherein, the resin comprises vinyl resin.

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