Carbon fiber reinforced PA self-resistance heating compression molding process

Abstract

The invention discloses a carbon fiber reinforced PA (polyamide) self-resistance heating compression molding process, which comprises the following steps of: pre-impregnating carbon fiber yarns in PA dispersed suspension at the speed of 1m / min, and drying at the temperature of 120 DEG C for later use; the preparation method comprises the following steps: weighing an aqueous solution of r-aminopropyltriethoxysilane and caprolactam, and mechanically blending with deionized water; pre-burying the pre-impregnated carbon fiber yarns matched with heating resistance wires on the surface of a press vulcanizer mold, then coating a layer of kerosene, and putting the mixed powder into the press vulcanizer mold for molding; the metal resistance wire is connected with a direct power supply and a temperature control system for heating, the temperature is raised to 145-165 DEG C, the temperature is kept for 50-60 min, pre-molding is conducted on the preformed blank, and the pressure is controlled to be 9-11 MPa; the temperature is rapidly increased to 185-195 DEG C, the temperature is kept for 50-60 min, the molded material is molded, then the temperature is reduced to 100 DEG C in a furnace cooling mode, the pressure is removed, the molded material and the mold are taken out, the molded material is cooled to the room temperature, and the carbon fiber reinforced PA composite material is obtained. According to the invention, the carbon fiber reinforced PA composite material is obtained by arranging the pre-impregnated carbon fiber yarns on the surface of the press vulcanizer mold in cooperation with the heating resistance wires, then coating the kerosene, filling the PA raw material, and carrying out resistance heating and compression molding, so that the strength performance of PA is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of reinforced nylon, and in particular relates to a carbon fiber reinforced PA self-resistance heating compression molding process. Background Art

[0002] Nylon 6 (PA6) has become one of the most widely used engineering plastics due to its excellent performance, ranking first among the five major engineering plastics. However, its poor resistance to strong acids and alkalis, insufficient dry toughness, low low-temperature impact strength, and easy burning have greatly limited the application of PA6. The advantages of PA6 itself are far from meeting people's expectations. In order to obtain materials with better performance and meet special requirements, research on nylon modification has become increasingly important.

[0003] In the early 1950s, fiber-reinforced polymer composites appeared. Fiber-reinforced polymer composites are materials with excellent composite properties, which are composed of organic polymers as the matrix and fibers as reinforcements. Among them, carbon fiber reinforced nylon composites are the most commonly used fiber-reinforced modified nylon methods.

[0004] The in-situ copolymerization method was used to disperse graphene oxide into caprolactam monomer at the initial stage of polymerization, solving the dispersion problem in nanoparticle modification. Then, ring-opening polymerization of caprolactam was carried out to graft nylon onto GO nanosheets to prepare graphene nylon 6 composite materials. Although a large number of carboxyl functional groups on graphene are conducive to the grafting of nylon, since carboxyl groups are end-capping agents for nylon, they will limit the growth of nylon chains during the polymerization process, resulting in the molecular weight of nylon gradually decreasing as the content of graphene oxide increases, which will eventually affect the performance of nylon.

[0005] Therefore, a carbon fiber reinforced PA self-resistance heating compression molding process needs to be studied urgently. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a carbon fiber reinforced PA self-resistance heating compression molding process, which is used to avoid the trouble of weakened performance after nylon modification in the past.

[0007] In order to solve the above technical problems, the present invention discloses a carbon fiber reinforced PA self-resistance heating compression molding process, which comprises: Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh an aqueous solution of r-aminopropyltriethoxysilane and caprolactam, and mechanically blend them with deionized water; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material.

[0008] According to one embodiment of the present invention, the r-aminopropyltriethoxysilane aqueous solution, caprolactam, and deionized water are respectively 60-80 parts, 200-4000 parts, and 50-70 parts by weight.

[0009] According to one embodiment of the present invention, the carbon fiber filaments are selected from any one of T600, T800 and T1000.

[0010] According to one embodiment of the present invention, kerosene is weighed at 22% wt.

[0011] According to one embodiment of the present invention, the carbon fiber filaments and the heating resistor filaments are arranged in a mesh shape.

[0012] Compared with the prior art, the present invention can achieve the following technical effects: The pre-impregnated carbon fiber filaments and heating resistance wires are laid on the surface of the flat vulcanizer mold, and then kerosene is coated, PA raw materials are filled, resistance heating is performed, and compression molding is performed to obtain a carbon fiber reinforced PA composite material, thereby improving the strength performance of PA.

[0013] Of course, any product implementing the present invention does not necessarily need to achieve all of the above-mentioned technical effects at the same time. DETAILED DESCRIPTION

[0014] The following will describe the implementation methods of the present invention in detail with reference to examples, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0015] The present invention discloses a carbon fiber reinforced PA self-resistance heating compression molding process, which comprises: Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh an aqueous solution of r-aminopropyltriethoxysilane and caprolactam, and mechanically blend them with deionized water; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material. Example 1

[0016] Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh r-aminopropyl triethoxysilane aqueous solution and caprolactam and mechanically blend them with deionized water; r-aminopropyl triethoxysilane aqueous solution and caprolactam are 60 parts, 200 parts and 50 parts by weight of deionized water, respectively; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material. Example 2

[0017] Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh r-aminopropyl triethoxysilane aqueous solution and caprolactam, and mechanically blend them with deionized water; r-aminopropyl triethoxysilane aqueous solution and caprolactam are 80 parts, 4000 parts, and 70 parts by weight of deionized water, respectively; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material. Example 3

[0018] Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh r-aminopropyl triethoxysilane aqueous solution and caprolactam and mechanically blend them with deionized water; r-aminopropyl triethoxysilane aqueous solution and caprolactam are 70 parts, 2000 parts and 60 parts by weight of deionized water, respectively; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material. Example 4

[0019] Step a. Weigh r-aminopropyl triethoxysilane aqueous solution and caprolactam, and mechanically blend them with deionized water; r-aminopropyl triethoxysilane aqueous solution and caprolactam are 80 parts, 4000 parts, and 70 parts by weight of deionized water, respectively; Step b. Place the mixed powder into a flat vulcanizing machine mold for molding; Step c. Heating in a reactor to 145-165°C for 50-60 min to preform the preformed blank, with the pressure controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a reinforced PA composite material.

[0020] The measured performance is shown in the following table: Project Name Yield strength / MPa Breaking strength / MPa Elastic modulus / MPa Example 1 90 160 3800 Example 2 88 170 4000 Example 3 100 250 4500 Example 4 80 120 3600 It can be seen from the data in the above table that the carbon fiber reinforced PA composite material obtained in Example 3 has the strongest performance.

[0021] Preferably, the carbon fiber filaments are selected from any one of T600, T800 and T1000.

[0022] Kerosene is weighed at 22% wt to facilitate demoulding of the carbon fiber filaments after hot melting, and fusion and stretching with PA mixed materials.

[0023] The carbon fiber wires and heating resistor wires are arranged in a mesh shape to ensure uniform heating.

[0024] In summary, the present invention arranges pre-impregnated carbon fiber filaments and heating resistance wires on the surface of a flat vulcanizer mold, then coats kerosene, fills PA raw materials, performs resistance heating, and performs compression molding to obtain a carbon fiber reinforced PA composite material, thereby improving the strength performance of PA.

[0025] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. Changes and variations made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A carbon fiber reinforced PA self-resistance heating compression molding process, characterized in that: include: Step a. Pre-impregnating the carbon fiber filaments in a PA dispersion suspension at a speed of 1 m / min and drying them at 120°C for standby use; Step b. Weigh an aqueous solution of r-aminopropyltriethoxysilane and caprolactam, and mechanically blend them with deionized water; Step c. pre-embed the pre-impregnated carbon fiber wire with the heating resistor wire on the surface of the flat vulcanizer mold, and then coat a layer of kerosene and place the mixed powder into the flat vulcanizer mold for molding; Step d. The metal resistance wire is directly connected to the power supply and the temperature control system for heating, rising to 145-165°C, and maintained for 50-60 minutes to pre-plasticize the preformed blank, and the pressure is controlled at 9-11 MPa; Step e. Rapidly raise the temperature to 185-195°C and maintain for 50-60 minutes to form the molding material, then cool it to 100°C by furnace cooling, remove the pressure, take it out together with the mold, and cool it to room temperature to obtain a carbon fiber reinforced PA composite material.

2. The carbon fiber reinforced PA self-resistance heating compression molding process according to claim 1 is characterized in that: The r-aminopropyltriethoxysilane aqueous solution, caprolactam and deionized water are respectively 60-80 parts, 200-4000 parts and 50-70 parts by weight.

3. The carbon fiber reinforced PA self-resistance heating compression molding process according to claim 1, characterized in that: The carbon fiber filaments are selected from any one of T600, T800 and T1000.

4. The carbon fiber reinforced PA self-resistance heating compression molding process according to claim 1, characterized in that: The kerosene is weighed at 22% wt.

5. The carbon fiber reinforced PA self-resistance heating compression molding process according to claim 1, characterized in that: The carbon fiber filaments and the heating resistor filaments are arranged in a mesh shape.