Carbon fiber sizing agent matched with (poly) dicyclopentadiene and application thereof

Abstract

The invention relates to a carbon fiber sizing agent matched with (poly) dicyclopentadiene for use and application of the carbon fiber sizing agent, and belongs to the technical field of poly dicyclopentadiene. The two most important components, namely the coupling agent (component 1) and the film-forming agent (component 2), of the sizing agent are synthesized through a one-pot method, separation, solvent recovery and washing purification are not needed, and the sizing agent is efficient and environmentally friendly. Finally, the introduction strategy of the coupling catalyst (component 3) is optimized, and the reaction efficiency of the carbon fiber and the sizing agent layer is improved to the maximum extent. The method is simple to operate, energy-saving, environment-friendly, high in reaction efficiency and good in interface enhancement effect, can realize batch production of the sizing agent, and can realize batch production of special carbon fibers.

Description

Technical Field

[0001] The invention belongs to the technical field of polydicyclopentadiene, and in particular relates to a carbon fiber sizing agent used in matching (poly)dicyclopentadiene and application thereof. Background Art

[0002] Polydicyclopentadiene (PDCPD) is a thermosetting resin. Compared with epoxy resin, it has the advantages of low moisture absorption, high strength and impact resistance. At the same time, since its raw material (dicyclopentadiene) is a by-product of petroleum distillation and there is no small molecule release during the curing process, it also has environmental advantages. Therefore, it has developed rapidly in recent years. The viscosity of dicyclopentadiene (DCPD) resin matrix can be as low as 0.1Pa·s, so it is a composite resin matrix with excellent molding ability. When the reinforcement is carbon fiber (CF), because the interface energy of both is low and lacks effective interaction, the interface bonding ability is poor, and the interface shear strength (IFSS) is as low as 13MPa (the IFSS of CF and epoxy resin under the same conditions is about 60MPa). Therefore, the interface energy absorption is a short board factor that restricts the application of CF-reinforced PDCPD resin-based composite materials.

[0003] In order to solve the above problems, the patent with publication number CN114478887A first uses supercritical swelling treatment, and then uses a silane coupling agent (4-(4-aminophenyl)benzonitrile triethanolsiloxane) to treat the carbon fiber, but the whole set of processes is complicated, especially the supercritical swelling treatment process cannot be applied to the continuous production of carbon fiber. In the patent with publication number TW202138643A, the carbon fiber is acidified and chlorinated, and then norbornene is grafted through an esterification reaction, but the chlorination and esterification processes require anhydrous and oxygen-free conditions, so they are not suitable for continuous production of carbon fiber. In the patent with publication number CN110387115A, the carbon fiber is washed with water and then treated with a silane coupling agent KH570, but the washing process cannot introduce functional groups on the surface of the carbon fiber that can interact with the silane coupling agent or PDCPD. The patent with publication number CN113400683A uses a secondary infusion method to prepare a composite material, but the secondary infusion process cannot introduce functional groups that can interact with silane coupling agents or PDCPD on the surface of carbon fibers; the patent with publication number CN116003943A improves the interaction with fibers by introducing epoxy resin into DCPD resin, but this loses the advantageous properties of low moisture absorption, high strength and impact resistance of PDCPD; the patents with publication numbers CN106366300A, CN106749949A, CN106749947A, CN106589250A, CN104448084A and CN102827318A all use silane coupling agents (such as KH570) to modify glass fibers to improve their interfacial bonding ability with PDCPD, but the surface of the glass fibers is rich in hydroxyl groups that can interact with silane coupling agents to produce chemical bonds, which is a property that carbon fibers do not have. In addition, the amino, hydroxyl, epoxy and other functional groups provided by conventional silane coupling agents cannot produce strong interactions with PDCPD, which is equivalent to improving the interfacial performance. KH570 can provide aliphatic ethylene functional groups, but the crosslinking mechanism of DCPD is ring-opening metathesis polymerization, which is different from aliphatic ethylene functional groups. Therefore, the chemical bond ability of KH570 and DCPD is limited, which leads to limited interface improvement ability. The patent with publication number CN116063823A uses norbornene-based silane coupling agent to treat CF. Norbornene has the same crosslinking mechanism as DCPD, both of which are ring-opening metathesis polymerization, but it still fails to improve the bonding problem between silane coupling agent and CF. Summary of the invention

[0004] In order to simultaneously solve the technical problems existing in the prior art of CF-reinforced PDCPD resin-based composite materials, the present invention provides a carbon fiber sizing agent based on click chemistry for matching (poly) dicyclopentadiene, which can be applied to the continuous production of carbon fibers, has chemical bond interaction between the coupling agent and the carbon fiber surface, has chemical bond interaction between the coupling agent and the PDCPD on the carbon fiber surface, has efficient and easy construction of chemical bond interaction, and is reasonably priced, and its application.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] A carbon fiber sizing agent for use with (poly) dicyclopentadiene according to the present invention, the sizing agent comprises a coupling agent and a film-forming agent, the coupling agent is recorded as component 1, and the film-forming agent is recorded as component 2;

[0007] The sizing agent is synthesized from dicyclopentadiene and a mercapto compound by a one-pot method, and purified by water washing. After water washing, the reaction system is directly used to prepare a solution-type or emulsion-type sizing agent.

[0008] The structural formula of the dicyclopentadiene is as follows:

[0009]

[0010] The structural formula of the thiol compound is as follows:

[0011]

[0012] Wherein, the three R groups are the same or different, and are one of the following structures, or one of the following branched derivatives containing a thiol structure, or one of the following hyperbranched derivatives containing a thiol structure, and at least one of the three R groups is not a hydrogen atom; n is any positive integer between 1 and 5;

[0013]

[0014] The sizing agent further comprises a coupling catalyst, which is recorded as component 3.

[0015] In the above technical solution, preferably, the molar ratio of component 1 to component 2 in the sizing agent is 1:0.8-1:5.

[0016] In the above technical solution, preferably, the molar ratio of dicyclopentadiene to the thiol compound is 2:1 to 5:1.

[0017] In the above technical solution, preferably, the solvent used for the synthesis of the sizing agent is toluene or acetonitrile, the catalyst is aluminum chloride, aluminum bromide, trifluoroacetic acid or methanesulfonic acid, and the concentration of the dicyclopentadiene is 0.1-2.0 mol / L.

[0018] In the above technical solution, preferably, the reaction temperature for the synthesis of the sizing agent is 60-200° C. and the time is 2-7 hours.

[0019] In the above technical scheme, preferably, the coupling catalyst is dibenzoyl peroxide and dimethylaniline, or azobisisobutylcyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutylcyanide.

[0020] A method for treating the surface of carbon fiber using the sizing agent of the present invention comprises the following steps:

[0021] When component 3 requires high temperature initiation or light initiation, the carbon fiber surface is treated by a one-step sizing or a two-step sizing method;

[0022] When component 3 requires room temperature initiation, the carbon fiber surface is treated by a two-step emulsion sizing method.

[0023] In the above technical scheme, preferably, when component 3 is azobisisobutyl cyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber surface is treated by one-step emulsion sizing or one-step solution sizing;

[0024] The one-step emulsion sizing method is used to treat the carbon fiber surface, including the following steps:

[0025] a. preparing a mixture of component 1 and component 2 into an emulsion, referred to as emulsion 1;

[0026] b. preparing component 3 into an emulsion, referred to as emulsion 2;

[0027] c. The emulsion 1, emulsion 2, antistatic agent, lubricant and deionized water in a mass ratio of 5 to 20: 0.5 to 10: 0.1 to 0.5: 0.2 to 0.8: the remainder, the remainder is the mass of deionized water, a total of 100 parts by mass, configured as an emulsion sizing agent;

[0028] d. When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sized and dried at 100-150°C before being rolled up; when component 3 is benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is first sized and then treated with ultraviolet rays, and then dried at 100-150°C before being rolled up;

[0029] The one-step solution sizing method is used to treat the carbon fiber surface, including the following steps:

[0030] a. The components 1 + component 2 (containing no solvent), component 3, an antistatic agent, a lubricant and an organic solvent in a mass ratio of 1 to 2: 0.01 to 0.1: 0.1 to 0.5: 0.2 to 0.8: the remainder is the mass of the organic solvent, a total of 100 parts by mass, configured as a solution-type sizing agent;

[0031] b. When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sizing and then dried at 120-150°C before being rolled up; when component 3 is benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, the carbon fiber is first sizing and then treated with ultraviolet rays, and then dried at 120-150°C before being rolled up.

[0032] In the above technical solution, preferably, the organic solvent used in the one-step emulsion sizing or one-step solution sizing is acetonitrile or toluene.

[0033] In the above technical scheme, preferably, when component 3 is dibenzoyl peroxide and dimethylaniline, or azobisisobutyl cyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is surface treated by a two-step emulsion sizing method, comprising the following steps:

[0034] a. preparing a mixture of component 1 and component 2 into an emulsion, referred to as emulsion 1;

[0035] b. preparing component 3 into an emulsion, referred to as emulsion 2;

[0036] c. The emulsion 1, antistatic agent, lubricant and deionized water in a mass ratio of: 5 to 20: 0.1 to 0.5: 0.2 to 0.8: the remainder, the remainder is the mass of deionized water, a total of 100 parts by mass, configured as an emulsion sizing agent;

[0037] d. The carbon fiber is first sized with emulsion 2, and then blown dry until no liquid drops. After sizing with emulsion 1, when component 3 is dibenzoyl peroxide and dimethylaniline, azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is dried at 100-150°C after sizing and then rolled up; when component 3 is benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is first sized and then treated with ultraviolet rays, and then dried at 100-150°C and rolled up.

[0038] The beneficial effects of the present invention are:

[0039] The advantages of the carbon fiber sizing agent used with (poly) dicyclopentadiene of the present invention are:

[0040] 1. Contains a series of thiol-containing coupling agents (one of the sizing agent components).

[0041] 2. The thiol-containing coupling agent and the film-forming agent (one of the sizing agent components) are synthesized by a one-pot direct synthesis process, without separation, solvent collection, water washing and purification. After water washing, the reaction system can be directly used to prepare a solution or emulsion sizing agent.

[0042] The method of using the coupling agent and the film-forming agent of the present invention to configure a special sizing agent and treat the surface of the carbon fiber can achieve in-situ chemical bonding with the surface of the carbon fiber during the sizing process. The specific advantages are as follows:

[0043] 1. The thiol-containing coupling agent developed in the present invention can produce chemical bond interactions with the carbon fiber surface through click chemistry reactions, with fast reaction rate and high reaction efficiency. During the sizing process, functional groups that can cross-link with DCPD can be introduced on the carbon fiber surface through carbon-sulfur bonds.

[0044] 2. The coupling agent and film-forming agent developed by the present invention are directly synthesized by a one-pot method, without separation or solvent recovery, and can be directly used to prepare a sizing agent after washing. It has industrialization capability, low cost, high efficiency and is green and environmentally friendly.

[0045] 3. The carbon fiber surface treatment method developed by the present invention does not contain acidification, chlorination, esterification and other anhydrous and oxygen-free reaction conditions, nor does it require high temperature and high pressure reaction conditions such as supercritical treatment. It can be achieved in an atmospheric environment using conventional carbon fiber production equipment, and has low requirements for equipment and personnel.

[0046] 4. The carbon fiber surface treatment method developed by the present invention improves the IFSS of commercially sized CF by 50%-130%. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0048] Figure 1 Schematic diagram of the one-pot synthesis reaction equation of component 1 and component 2.

[0049] Figure 2 Schematic diagram of the composition and chemical structure of component 1.

[0050] Figure 3 Schematic diagram of the composition and chemical structure of component 2. DETAILED DESCRIPTION

[0051] The inventive concept of the present invention is: in order to solve the technical problems in the prior art, it is necessary to construct an interface phase that can produce chemical bonds with both carbon fiber and DCPD, so three interface enhancement strategies are generated, which can be divided into resin first and fiber, simultaneous chemical bonds and fiber first and resin first according to the order of the interface phase and the two sides to produce chemical bonds. The construction method of resin first and fiber second requires the overall modification of the resin matrix, which is not only costly, but also easy to damage the advantageous characteristics of the resin matrix itself; the strategy of simultaneous chemical bonds is usually implemented during the processing process, DCPD usually has a low viscosity, and it is easy to dissolve the unstable interface phase during the preforming process; the strategy of CF first and resin second can be implemented through the sizing process, which is easy to operate and has low dependence on equipment and personnel. Therefore, the present invention adopts: during the sizing process, a chemical reaction is constructed between CF and the sizing agent (interface phase), and at the same time, the sizing agent (interface phase) maintains a cross-linking group similar to that of DCPD. Based on this strategy, the present invention first designs and develops a highly active coupling agent, which can interact with the unsaturated bonds on the surface of carbon fibers through conditional click chemistry reactions to form chemical bonds, while retaining part of the dicyclopentadiene / tricyclopentadiene structure, that is, retaining the ability to crosslink with the DCPD matrix. Based on this, the present invention further optimizes the coupling agent synthesis process, so that the two most important components of the sizing agent, the coupling agent (component 1) and the film-forming agent (component 2), are synthesized by a one-pot method (see the reaction equation). Figure 1 Component 1 is a mixture of corresponding R structures, and its structural formula is shown in Figure 2 , component 2 structural formula see Figure 3 ), no need for separation, no need for solvent recovery, water washing and purification, efficient and green and environmentally friendly. Finally, the present invention optimizes the introduction strategy of the coupling catalyst (component 3) to maximize the reaction efficiency of the carbon fiber and the sizing agent layer. The present invention is simple to operate, energy-saving and environmentally friendly, has high reaction efficiency, good interface enhancement effect, can realize batch production of sizing agents, and can realize batch production of special carbon fibers.

[0052] A carbon fiber sizing agent for use with (poly) dicyclopentadiene according to the present invention, the sizing agent comprises a coupling agent and a film-forming agent, the coupling agent is recorded as component 1, and the film-forming agent is recorded as component 2;

[0053] The sizing agent is synthesized from dicyclopentadiene and a mercapto compound by a one-pot method, and purified by water washing. After water washing, the reaction system can be directly used to prepare a solution or emulsion type sizing agent;

[0054] The structural formula of the dicyclopentadiene is as follows:

[0055]

[0056] The structural formula of the thiol compound is as follows:

[0057]

[0058] Wherein, the three R groups are the same or different, and are one of the following structures, or one of the following branched derivatives containing a thiol structure, or one of the following hyperbranched derivatives containing a thiol structure, and at least one of the three R groups is not a hydrogen atom; n is any positive integer between 1 and 5;

[0059]

[0060] The sizing agent further comprises a coupling catalyst, which is recorded as component 3.

[0061] The sizing agent is synthesized from dicyclopentadiene and a thiol compound by a one-pot method, and purified by water washing. After water washing, the reaction system can be directly used to prepare a solution or emulsion type sizing agent. The present invention is achieved by the following steps:

[0062] (1) adding DCPD to a reaction kettle, sealing the reaction kettle, evacuating nitrogen three times, injecting an organic solvent, and stirring to fully dissolve the DCPD; adding a catalyst and stirring evenly; dissolving a thiol compound in an organic solvent and adding the mixture dropwise to the reaction kettle; heating the mixture to a specified temperature, and cooling the mixture to room temperature after the reaction is completed; filtering to remove residues, washing the filtrate with water three times, and separating the liquids to obtain a mixed solution of component 1 and component 2 in a specific ratio (hereinafter referred to as the raw solution);

[0063] (2) The stock solution can be diluted and then added with component 3, antistatic agent and lubricant to be used directly as a one-step solution sizing agent, or an emulsifier and deionized water can be added to prepare emulsion 1 for standby use;

[0064] or (3) dissolving component 3 in an organic solvent, adding an emulsifier and deionized water to prepare emulsion 2;

[0065] (4) According to different sizing methods, a one-step solution sizing agent, a one-step emulsion sizing agent or a two-step emulsion sizing agent is respectively prepared; the surface modification of carbon fiber is achieved by one-step solution sizing, one-step emulsion sizing or two-step emulsion sizing, and the coupling agent can efficiently interact with CF to produce chemical bonds during the sizing (including drying) process, while retaining part of the dicyclo / tricyclopentadiene structure.

[0066] Furthermore, in the above step (1), the molar ratio of the reactant dicyclopentadiene to the thiol compound is 2:1 to 5:1;

[0067] Furthermore, the organic solvent used in the above step (1) is toluene or acetonitrile, and the concentration of dicyclopentadiene is 0.1-2.0 mol / L, more preferably 0.1-1.0 mol / L;

[0068] Furthermore, the catalyst used in the above step (1) is aluminum chloride, aluminum bromide, trifluoroacetic acid or methanesulfonic acid;

[0069] Furthermore, in the above step (1), the temperature of the synthesis reaction of component 1 and component 2 is 60-200°C;

[0070] Furthermore, the time for the synthesis reaction of component 1 and component 2 in the above step (1) is 2-7 hours;

[0071] Furthermore, in the above step (1), the molar ratio of component 1 to component 2 in the stock solution is 1:0.8-1:5;

[0072] Furthermore, the mass fraction of component 1 + component 2 in the emulsion 1 prepared in the above step (2) is 10% to 20%;

[0073] Preferably, the oil-water ratio of the emulsion 1 prepared in the above step (2) is 1:1 to 1:2;

[0074] Furthermore, in the above step (3), component 3 is: dibenzoyl peroxide + dimethylaniline, azobisisobutyl cyanide, dibenzoyl peroxide, benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide; when component 3 requires high temperature initiation or light initiation, the carbon fiber surface is treated by a one-step sizing or a two-step sizing method; when component 3 requires room temperature initiation, the carbon fiber surface is treated by a two-step emulsion sizing method.

[0075] Furthermore, the mass fraction of component 3 in the emulsion 2 prepared in the above step (3) is 10% to 20%;

[0076] Preferably, the oil-water ratio of the emulsion 2 prepared in the above step (3) is 1:1 to 1:2;

[0077] Furthermore, in the above step (4), when component 3 is azobisisobutyl cyanide, dibenzoyl peroxide, benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, a one-step emulsion sizing, one-step solution sizing or two-step emulsion sizing method for treating the carbon fiber surface can be used;

[0078] Furthermore, in the above step (4), when component 3 is dibenzoyl oxide + dimethylaniline, only the carbon fiber surface treatment method of two-step emulsion sizing can be used;

[0079] Furthermore, the method for treating the carbon fiber surface by one-step emulsion sizing in the above step (4) is specifically as follows:

[0080] ① Prepare an emulsion type sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5-20:0.5-10:0.1-0.5:0.2-0.8: the remainder (a total of 100);

[0081] ② When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sizing and then dried at 100-150°C before being rolled up; when component 3 is benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, the carbon fiber is first sizing and then treated with ultraviolet rays, and then dried at 100-150°C before being rolled up.

[0082] Furthermore, the method for treating the carbon fiber surface by one-step solution sizing in the above step (4) is specifically as follows:

[0083] ① Component 1 + component 2 (without solvent), component 3, antistatic agent, lubricant and organic solvent are configured into a solution-type sizing agent in a mass ratio of 1-2: 0.01-0.1: 0.1-0.5: 0.2-0.8: the remainder (a total of 100);

[0084] ② When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sizing and then dried at 120-150°C before being rolled up; when component 3 is benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, the carbon fiber is first sizing and then treated with ultraviolet rays, and then dried at 120-150°C before being rolled up.

[0085] Furthermore, the method for treating the carbon fiber surface by two-step emulsion sizing in step (4) above is specifically as follows:

[0086] ① Prepare an emulsion sizing agent by mixing emulsion 1, an antistatic agent, a lubricant and deionized water in a mass ratio of 5-20:0.1-0.5:0.2-0.8: the remainder (a total of 100);

[0087] ② The carbon fiber is first sized with emulsion 2, then blown dry until no liquid drops, and then sized with emulsion 1. When component 3 is dibenzoyl peroxide + dimethylaniline, azobisisobutyl cyanide, or dibenzoyl peroxide, the carbon fiber is dried at 100-150°C after sizing and then rolled up; when component 3 is benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, the carbon fiber is first sized and then treated with ultraviolet rays, and then dried at 100-150°C and rolled up.

[0088] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0089] The amount of catalyst used in the following examples can be based on the conventional catalytic amount in the art, and the present invention does not make any special restrictions. As for the antistatic agent, lubricant and emulsifier, as long as they can achieve their functions, there is no special restriction on their respective types.

[0090] Example 1

[0091] (1) Add 132.2 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add 5 g of aluminum chloride and stir evenly; dissolve 55.1 g of thiophenol in 3 L of toluene and add dropwise to the reactor; heat to 60° C., react for 2 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:0.8 (hereinafter referred to as the stock solution);

[0092] (2) After the stock solution is diluted, azobisisobutyl cyanide, an antistatic agent and a lubricant are added to prepare a one-step solution sizing agent, and component 1 + component 2 (without solvent), azobisisobutyl cyanide, an antistatic agent, a lubricant and toluene are prepared in a mass ratio of 1:0.01:0.1:0.2: the remainder (a total of 100) to prepare a solution sizing agent;

[0093] (3) After sizing, the carbon fiber is dried at 120°C and then rolled up;

[0094] (4) The IFSS of carbon fiber and PDCPD after sizing is 18 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0095] Example 2

[0096] (1) Add 2644 g DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L acetonitrile, and stir to fully dissolve DCPD; add a catalytic amount of aluminum bromide and stir evenly; dissolve 496.8 g benzyl mercaptan in 3 L acetonitrile and add dropwise to the reactor; heat to 200° C., react for 7 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0097] (2) After the stock solution is diluted, dibenzoyl peroxide, antistatic agent and lubricant are added to prepare a one-step solution sizing agent, and component 1 + component 2 (without solvent), dibenzoyl peroxide, antistatic agent, lubricant and toluene are prepared in a mass ratio of 2:0.1:0.5:0.8: the remainder (a total of 100) to prepare a solution sizing agent; (3) After sizing, the carbon fiber is dried at 150°C and then rolled;

[0098] (4) The IFSS of carbon fiber and PDCPD after sizing is 27.6MPa, and the IFSS of commercially sized CF and PDCDP is 12MPa.

[0099] Example 3

[0100] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 552.62 g of 2-phenylethanethiol in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0101] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0102] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0103] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0104] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0105] (6) The IFSS of carbon fiber and PDCPD after sizing is 25 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0106] Example 4

[0107] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of methanesulfonic acid and stir evenly; dissolve 609.2 g of 3-phenylpropanethiol in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0108] (2) Add toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 60%, add deionized water and emulsifier twice the volume of the organic solution, and emulsify under stirring. The above emulsion, antistatic agent, lubricant and deionized water are prepared in a mass ratio of 20:0.5:0.8: the remainder (a total of 100) to form emulsion 1;

[0109] (3) dissolving benzoin dimethyl ether in toluene (mass fraction 60%), adding deionized water and an emulsifier twice the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:2, and the mass fraction of component 1 + component 2 is 20%);

[0110] (4) The carbon fiber is sized with emulsion 1 and then blown dry until no liquid drops fall, then sized with emulsion 2, then treated with ultraviolet light, and finally dried at 130°C and rolled up;

[0111] (5) The IFSS of carbon fiber and PDCPD after sizing is 22 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0112] Example 5

[0113] (1) Add 2644 g DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L toluene, and stir to fully dissolve the DCPD; add a catalytic amount of methanesulfonic acid and stir evenly; dissolve 665.2 g 4-phenylbutanethiol in 3 L toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0114] (2) Add toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 60%, add deionized water and emulsifier twice the volume of the organic solution, and emulsify under stirring. The above emulsion, antistatic agent, lubricant and deionized water are prepared in a mass ratio of 20:0.5:0.8: the remainder (a total of 100) to form emulsion 1;

[0115] (3) dissolving dibenzoyl oxide + dimethylaniline in a molar ratio of 1:1 in toluene (mass fraction of 60%), adding deionized water and an emulsifier twice the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:2, and the mass fraction of component 1 + component 2 is 20%);

[0116] (4) The carbon fiber is sized with emulsion 1 and then blown dry until no liquid drops fall, then sized with emulsion 2, then treated with ultraviolet light, and finally dried at 130°C and rolled up;

[0117] (5) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0118] Example 6

[0119] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of methanesulfonic acid and stir evenly; dissolve 665.2 g of 4-phenylpentanethiol in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 in a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0120] (2) Add toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 60%, add deionized water and emulsifier twice the volume of the organic solution, and emulsify under stirring. The above emulsion, antistatic agent, lubricant and deionized water are prepared in a mass ratio of 20:0.5:0.8: the remainder (a total of 100) to form emulsion 1;

[0121] (3) dissolving benzophenone oxide + azobisisobutyl cyanide in a molar ratio of 1:1 in toluene (mass fraction of 60%), adding deionized water and an emulsifier twice the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:2, and the mass fraction of component 1 + component 2 is 20%);

[0122] (4) The carbon fiber is sized with emulsion 1 and then blown dry until no liquid drops fall, then sized with emulsion 2, then treated with ultraviolet light, and finally dried at 130°C and rolled up;

[0123] (5) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0124] Example 7

[0125] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 672.8 g of phenyl thioglycolate in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 in a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0126] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0127] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0128] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0129] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0130] (6) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0131] Example 8

[0132] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 952.8 g of phenylpentyl thioglycolate in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove the residue, wash the filtrate with water three times, and separate the liquids to obtain a mixed solution of component 1 and component 2 in a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0133] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0134] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0135] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0136] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0137] (6) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0138] Example 9

[0139] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 625.2 g of 3-mercaptobenzyl mercaptan in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate to obtain a mixed solution of component 1 and component 2 in a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0140] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0141] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0142] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0143] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0144] (6) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0145] Example 10

[0146] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 865.6 g of 1,3,5-tris(mercaptomethyl)benzene in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0147] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0148] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0149] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0150] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0151] (6) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0152] Embodiment 11

[0153] (1) Add 2644 g of DCPD to a reactor, seal the reactor, evacuate nitrogen three times, inject 7 L of toluene, and stir to fully dissolve the DCPD; add a catalytic amount of trifluoroacetic acid and stir evenly; dissolve 865.6 g of 1,3,5-tris(mercaptomethyl)benzene in 3 L of toluene and add dropwise to the reactor; heat to 180° C., react for 5 h, and cool to room temperature after the reaction is completed; filter to remove residue, wash the filtrate with water three times, and separate to obtain a mixed solution of component 1 and component 2 with a molar ratio of 1:5 (hereinafter referred to as the stock solution);

[0154] (2) adding toluene to dilute the stock solution to a mass fraction of component 1 + component 2 of 20%, adding deionized water and an emulsifier equal in volume to the organic solution, and preparing emulsion 1 under stirring (the oil-water ratio in emulsion 1 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0155] (3) dissolving benzoin dimethyl ether in toluene (mass fraction of 20%), adding deionized water and emulsifier in an amount equal to the volume of the organic solution, and preparing emulsion 2 under stirring (the oil-water ratio in emulsion 2 is 1:1, and the mass fraction of component 1 + component 2 is 10%);

[0156] (4) preparing a one-step emulsion sizing agent by mixing emulsion 1, emulsion 2, an antistatic agent, a lubricant and deionized water in a mass ratio of 5:0.5:0.1:0.2: the remainder (a total of 100);

[0157] (5) the carbon fiber is treated with ultraviolet light after being sizing agent prepared by the one-step emulsion sizing agent in step (4), and finally dried at 130° C. and rolled up;

[0158] (6) The IFSS of carbon fiber and PDCPD after sizing is 23 MPa, and the IFSS of commercially sized CF and PDCDP is 12 MPa.

[0159] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A carbon fiber sizing agent for use with (poly) dicyclopentadiene, characterized in that: The sizing agent includes a coupling agent and a film-forming agent, wherein the coupling agent is recorded as component 1, and the film-forming agent is recorded as component 2; The sizing agent is synthesized from dicyclopentadiene and a mercapto compound by a one-pot method, and purified by water washing. After water washing, the reaction system is directly used to prepare a solution-type or emulsion-type sizing agent. The structural formula of the dicyclopentadiene is as follows: The structural formula of the thiol compound is as follows: Wherein, the three R groups are the same or different, and are one of the following structures, or one of the following branched derivatives containing a thiol structure, or one of the following hyperbranched derivatives containing a thiol structure, and at least one of the three R groups is not a hydrogen atom; n is any positive integer between 1 and 5; The sizing agent further comprises a coupling catalyst, which is recorded as component 3.

2. The carbon fiber sizing agent according to claim 1, characterized in that The molar ratio of component 1 to component 2 in the sizing agent is 1:0.8-1:

5.

3. The carbon fiber sizing agent according to claim 1, characterized in that: The molar ratio of the dicyclopentadiene to the mercapto compound is 2:1 to 5:

1.

4. The carbon fiber sizing agent according to claim 1, characterized in that The solvent used for synthesizing the sizing agent is toluene or acetonitrile, the catalyst is aluminum chloride, aluminum bromide, trifluoroacetic acid or methanesulfonic acid, and the concentration of the dicyclopentadiene is 0.1-2.0 mol / L.

5. The carbon fiber sizing agent according to claim 1, characterized in that: The reaction temperature for synthesizing the sizing agent is 60-200° C. and the time is 2-7 hours.

6. The carbon fiber sizing agent according to claim 1, characterized in that: The coupling catalyst is dibenzoyl peroxide and dimethylaniline, or azobisisobutylcyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutylcyanide.

7. A method for treating the surface of carbon fiber using the carbon fiber sizing agent according to claim 1, characterized in that: The following steps are involved: When component 3 requires high temperature initiation or light initiation, the carbon fiber surface is treated by a one-step sizing or a two-step sizing method; When component 3 requires room temperature initiation, the carbon fiber surface is treated by a two-step emulsion sizing method.

8. The carbon fiber surface treatment method according to claim 7, characterized in that: When component 3 is azobisisobutyl cyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber surface is treated by one-step emulsion sizing or one-step solution sizing; The one-step emulsion sizing method is used to treat the carbon fiber surface, including the following steps: a. preparing a mixture of component 1 and component 2 into an emulsion, referred to as emulsion 1; b. preparing component 3 into an emulsion, referred to as emulsion 2; c. The emulsion 1, emulsion 2, antistatic agent, lubricant and deionized water in a mass ratio of 5 to 20: 0.5 to 10: 0.1 to 0.5: 0.2 to 0.8: the remainder, the remainder is the mass of deionized water, a total of 100 parts by mass, configured as an emulsion sizing agent; d. When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sized and dried at 100-150°C before being rolled up; when component 3 is benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is first sized and then treated with ultraviolet rays, and then dried at 100-150°C before being rolled up; The one-step solution sizing method is used to treat the carbon fiber surface, including the following steps: a. The components 1 + component 2 (containing no solvent), component 3, an antistatic agent, a lubricant and an organic solvent in a mass ratio of 1 to 2: 0.01 to 0.1: 0.1 to 0.5: 0.2 to 0.8: the remainder, the remainder being the mass of the organic solvent, a total of 100 parts by mass, are configured as a solution-type sizing agent; b. When component 3 is azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is sizing and then dried at 120-150°C before being rolled up; when component 3 is benzoin dimethyl ether or benzophenone + azobisisobutyl cyanide, the carbon fiber is first sizing and then treated with ultraviolet rays, and then dried at 120-150°C before being rolled up.

9. The carbon fiber surface treatment method according to claim 8, characterized in that: The organic solvent used in one-step emulsion sizing or one-step solution sizing is acetonitrile or toluene.

10. The carbon fiber surface treatment method according to claim 7, characterized in that: When component 3 is dibenzoyl peroxide and dimethylaniline, or azobisisobutyl cyanide, or dibenzoyl peroxide, or benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is surface treated by a two-step emulsion sizing method, comprising the following steps: a. preparing a mixture of component 1 and component 2 into an emulsion, referred to as emulsion 1; b. preparing component 3 into an emulsion, referred to as emulsion 2; c. The emulsion 1, antistatic agent, lubricant and deionized water in a mass ratio of: 5 to 20: 0.1 to 0.5: 0.2 to 0.8: the remainder, the remainder is the mass of deionized water, a total of 100 parts by mass, configured as an emulsion sizing agent; d. The carbon fiber is first sized with emulsion 2, and then blown dry until no liquid drops. After sizing with emulsion 1, when component 3 is dibenzoyl peroxide and dimethylaniline, azobisisobutyl cyanide or dibenzoyl peroxide, the carbon fiber is dried at 100-150°C after sizing and then rolled up; when component 3 is benzoin dimethyl ether, or benzophenone and azobisisobutyl cyanide, the carbon fiber is first sized and then treated with ultraviolet rays, and then dried at 100-150°C and rolled up.

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