A manufacturing process of glass fiber reinforced plastic cylinder

Abstract

The present invention relates to a manufacturing process for a glass fiber reinforced plastic cylinder, and belongs to the technical field of glass fiber reinforced plastic preparation. The manufacturing process includes the following steps: S1, cleaning and demoulding; S2, laying glass fiber mesh cloth and closing the mold; S3, mold preheating; S4, rubber preparation; S5, vacuum pouring; S6, curing and demoulding; S7, post-processing. Glass fiber mesh cloth is used in this process. The mesh on the mesh cloth can facilitate the flow of rubber. The addition of flame retardant powder to the rubber can improve the flame retardant ability of the product. The filler can prevent the product from imploding and cracking, and at the same time can reduce the cost of the product. The density is increased by vacuum pouring, and the mechanical properties of the product are improved by high-temperature curing. This process can reduce costs and improve production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of glass fiber reinforced plastic preparation, and relates to a manufacturing process of a glass fiber reinforced plastic cylinder. Background Art

[0002] In medical devices, especially MRI (magnetic resonance imaging) equipment, the transmitting coil cylinder plays a crucial role. Fiberglass, a composite material made from resin and glass fiber through a composite process, is widely used in the medical device field due to its advantages such as light weight, high strength, corrosion resistance, excellent insulation, and high designability. Therefore, as an advanced composite material, fiberglass is widely used in the manufacture of these transmitting coil cylinders due to its unique properties.

[0003] With the continuous development and popularization of MRI technology, the performance requirements for transmit coil cylinders are becoming increasingly stringent. Flame-retardant fiberglass cylinders, due to their excellent flame retardancy, lightweight and high strength, excellent mechanical properties, and ease of processing and molding, are finding increasing application in MRI equipment. This excellent flame retardancy can effectively prevent the spread of fire in extreme situations, such as fire, protecting the safety of MRI equipment and patients.

[0004] Therefore, it is necessary to develop a preparation process for a FRP cylinder with excellent flame retardancy and mechanical properties. Summary of the Invention

[0005] The present invention aims to provide a process for manufacturing a fiberglass reinforced plastic cylinder. This process uses a fiberglass mesh, the mesh openings of which facilitate the flow of the rubber compound. The addition of flame retardant powder to the rubber compound enhances the product's flame retardancy, and the filler prevents implosion and cracking, while also reducing product cost. Vacuum casting increases density, and high-temperature curing enhances the product's mechanical properties. This process reduces costs and improves production efficiency.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A manufacturing process of a glass fiber reinforced plastic cylinder comprises the following steps:

[0008] S1. Cleaning and demoulding:

[0009] Clean the mold with acetone, dry it at 60°C for 24 hours, and evenly apply a layer of polyethylene wax release agent on the dry mold surface;

[0010] S2. Laying fiberglass mesh and closing the mold:

[0011] Lay the fiberglass mesh in the mold, roll it to remove air bubbles, and then close the mold together, making sure all edges and gaps are tightly fitted;

[0012] S3, mold preheating:

[0013] After checking the air tightness, preheat the mold and keep it at 80~100℃ for 1~2h;

[0014] S4. Rubber preparation:

[0015] The epoxy resin was preheated at 80°C for 30 minutes, and then epoxy resin: curing agent: flame retardant powder: filler with a mass ratio of (25-30): (25-30): (28-32): 15 was stirred in a stirred tank at a speed of 1000 r / min for 30-50 minutes, and a rubber compound was prepared by vacuum degassing.

[0016] S5. Vacuum casting:

[0017] The vacuum degree in the mold is reduced to -0.85~-0.95MPa, and then the rubber material is introduced into the mold from the bottom, and poured from bottom to top until the rubber material fills the top outlet of the mold. Then the valve at the top outlet of the mold is closed, and the pressure of the mold filled with rubber material is increased to 0.6~0.7MPa at a pressure increase rate of 0.1MPa / min. The valve is closed for 2 minutes, opened for 30 seconds, and the pressure is maintained for 10~15 minutes.

[0018] S6, curing and demoulding:

[0019] The mold after step S5 is cured at high temperature, and after complete curing, it is naturally cooled to room temperature, demoulded, and CNC trimmed to obtain the glass fiber reinforced plastic cylinder A;

[0020] S7, post-processing:

[0021] The surface of the glass fiber reinforced plastic cylinder A after step S6 is subjected to sandblasting and paint spraying to obtain the glass fiber reinforced plastic cylinder.

[0022] As a preferred technical solution of the present invention, in step S4, the preparation process of the filler is as follows:

[0023] S2.1. Mix quartz powder and aluminate coupling agent in a mass ratio of 30:1, ball mill at 300 r / min for 3 h, and pass through a 200-mesh sieve to obtain mixture A. Then, add anhydrous ethanol (7 times the mass of mixture A) and stir at 500 r / min at 40-45°C for 1-2 h. Heat to 100-120°C and dry for 12 h to obtain mixture B.

[0024] S2.2. A mixture of B, polyacrylamide and deionized water in a mass ratio of 10:1:25 was stirred at a constant speed for 1-2 h. After drying, solid C was obtained. Solid C was ground at a speed of 300 r / min for 3 h and then passed through a 300-mesh sieve to obtain modified quartz powder.

[0025] As a preferred technical solution of the present invention, in step S4, the flame retardant powder is prepared as follows:

[0026] S3.1, in parts by weight, at room temperature, 10 to 15 parts of barium carbonate were dispersed in 70 to 90 parts of deionized water to obtain a suspension A, and 10 to 15 parts of phytic acid were dissolved in 65 parts of deionized water to obtain a phytic acid solution. The phytic acid solution and suspension A were mixed and stirred at a speed of 300 to 400 r / min for 5 h. After the stirring, the mixture was filtered, washed with deionized water, and dried to obtain a barium phytate solid.

[0027] S3.2. Aluminum hydroxide and barium phytate solids in a mass ratio of (3-5):1 are stirred at a speed of 300-400 r / min for 20-30 min to obtain a mixture C, 20 parts of the mixture C are mixed with 20-25 parts of the lignin mixed solution, stirred at a speed of 300-400 r / min for 2-4 h, dried at 80-95 ° C for 15 h, and then ball milled at a speed of 300 r / min for 1 h to obtain the flame retardant powder.

[0028] As a preferred technical solution of the present invention, in step S2, the glass fiber mesh is a twist-free reinforced mesh.

[0029] As a preferred technical solution of the present invention, in step S6, the process of curing at high temperature is: first raising the temperature to 100°C and keeping it for 2-3 hours, and then raising the temperature to 125°C and keeping it for 4-5 hours.

[0030] As a preferred technical solution of the present invention, in step S7, the sand used in the sandblasting treatment is quartz sand material with a particle size of 100 mesh and a treatment pressure of 5.0 MPa.

[0031] As a preferred technical solution of the present invention, in step S7, the paint is epoxy resin paint.

[0032] As a preferred technical solution of the present invention, in step S2.2, the drying condition is drying at 90° C. for 12 hours.

[0033] As a preferred technical solution of the present invention, in step S3.1, the drying condition is drying at 75-80°C for 12-17 hours.

[0034] As a preferred technical solution of the present invention, in step S3.2, the lignin mixture contains nano-lignin, ethanol and water in a mass ratio of 2:2:7.

[0035] The invention adds flame retardant powder to the epoxy resin, which can improve the flame retardancy of the product. The filler can prevent the product from imploding and cracking, and can reduce the product cost.

[0036] During the preparation of flame retardant powder, barium phytate is first prepared and then mixed with aluminum hydroxide, so that phosphorus can be introduced into aluminum hydroxide. The phosphorus element in barium phytate can promote the formation of a carbon layer on the surface of the material during combustion, thereby preventing heat and oxygen from transferring to the interior of the material and reducing the generation of combustible gases. It complements the flame retardant mechanisms of aluminum hydroxide such as heat absorption and dilution, and enhances the overall flame retardant effect through synergistic effects.

[0037] Furthermore, the addition of lignin, which readily forms a char layer during combustion, combined with the char-forming effect of barium phytate, further enhances the material's charring ability. Furthermore, the lignin mixture allows aluminum hydroxide and barium phytate to mix better, forming a uniform mixture. It also acts as a dispersant, evenly distributing the flame retardant powder components throughout the rubber compound. This prevents localized over- or under-concentration of the powder within the epoxy resin, ensuring the powder's performance stability.

[0038] A flame retardant system composed of aluminum hydroxide and barium phytate can increase the brittleness of the material, leading to cracking and breakage during the overall process of casting the rubber compound or during the use of the FRP cylinder. Lignin has certain flexibility and adhesive properties, so adding lignin to the flame retardant powder can also improve the toughness of the rubber compound, reduce the brittleness of the material, and increase its durability.

[0039] The filler is obtained by treating quartz powder with an aluminate coupling agent and polyacrylamide. The quartz surface is usually relatively inert. After being treated with an aluminate coupling agent, new active functional groups can be introduced into the quartz surface, thereby increasing the surface activity of the quartz, making it more compatible with the polarity of the epoxy resin matrix, enhancing the interfacial affinity between the quartz and the resin, and improving the compatibility between the two.

[0040] At the same time, when the quartz particles treated with the aluminate coupling agent are close to each other, the interaction between the coupling agent molecular chains prevents the particles from agglomerating, allowing the quartz to be more evenly dispersed in the epoxy resin.

[0041] Polyacrylamide molecular chains contain numerous polar groups, which can interact with coupling agents or other active sites on the surface of the quartz powder in Mixture B, further improving the surface properties of the quartz powder. Polyacrylamide forms a protective polymer film on the quartz powder surface, providing excellent dispersing and thickening properties, enabling better dispersion of the quartz powder. Certain groups on the ammonium polyacrylate molecular chain can chemically react or physically entangle with the polymer matrix, forming a bridge between the quartz powder and the polymer, allowing them to better bond and enhance the overall performance of the composite. Furthermore, quartz powder has a high oil absorption value, often requiring more resin, which affects production costs and material processing performance. Modification can reduce the oil absorption of quartz powder, allowing it to mix more efficiently with epoxy resin during composite preparation, reducing resin consumption, lowering costs, and improving processing performance.

[0042] Beneficial effects of the present invention:

[0043] (1) In this process, the mold is first cleaned and demoulded to ensure that there is no oil or impurities. Then, a glass fiber mesh is laid. The mesh on the mesh can facilitate the flow of the rubber. The mold is preheated before the rubber is poured. The rubber is poured from bottom to top. During the rising filling process, the rubber can gradually squeeze the small amount of air remaining in the mold upward and discharge it from the top outlet, further ensuring that there are no bubbles, pores and other defects inside the product. Compared with pouring from top to bottom, the rubber introduced from the bottom can make the rubber fill the mold cavity more smoothly, improve the integrity and uniformity of the filling, reduce the turbulence and splashing of the rubber during the flow process, avoid local stress concentration or uneven distribution of the rubber caused by the impact of the rubber, and help improve the stability of product quality. In addition, since flame retardant powder is added to the rubber, the flame retardant ability of the product can be improved. The added filler can prevent the product from exploding and cracking, while reducing the cost of the product. At the same time, the pressure maintenance during the pouring process can reduce the voids in the product and increase the density.

[0044] (2) During the pouring process, the pressure increase rate is 0.1 MPa / min. By slowly increasing the pressure, the rubber compound can have enough time to adapt to the pressure change in the mold, avoiding the rubber compound flowing too fast or generating turbulence due to the sudden increase in pressure, thereby ensuring the uniform distribution of the rubber compound in the mold. The valve is closed for 2 minutes and opened for 30 seconds to balance the pressure. Opening the valve can release the local excessive pressure in the mold caused by the curing of the rubber compound, making the pressure distribution in the mold more uniform, avoiding the damage of the mold caused by the local excessive pressure or causing defects in the product. Then, by maintaining the pressure, the rubber compound is fully cured, stress is eliminated, and quality is improved.

[0045] (3) Through high temperature curing and the use of two temperature stage temperature settings, the mechanical properties of the product can be improved. This process can reduce costs and improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0047] Figure 1 This is the overall process flow chart of this process. DETAILED DESCRIPTION

[0048] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0049] In the comparative examples and embodiments of the present invention:

[0050] The glass fiber mesh used is a twist-free woven reinforced mesh, model ENG260L-1130; the epoxy resin used is MERICAN 3221A; the curing agent used is MERICAN 3221B; quartz was purchased from Huachang Polymer Co., Ltd. of East China University of Science and Technology; aluminate coupling agent was purchased from Hubei Fangde New Materials Co., Ltd.; polyacrylamide was purchased from Shanghai Yuanye Biotechnology Co., Ltd.; aluminum hydroxide was purchased from Huachang Polymer Co., Ltd. of East China University of Science and Technology; and lignin was purchased from Yigao Zhuoxin Energy Saving Technology (Shanghai) Co., Ltd.

[0051] Example 1

[0052] Preparation of filler:

[0053] S2.1. Mix quartz powder and aluminate coupling agent in a mass ratio of 30:1, ball mill at 300 r / min for 3 h, and pass through a 200-mesh sieve to obtain mixture A. Then, add anhydrous ethanol (7 times the mass of mixture A), stir at 500 r / min at 40°C for 1 h, heat to 100°C, and dry for 12 h to obtain mixture B.

[0054] S2.2. A mixture of B, polyacrylamide and deionized water in a mass ratio of 10:1:25 was stirred at a constant speed for 1 hour, and dried at 90°C for 12 hours to obtain solid C. Solid C was ground at a speed of 300 r / min for 3 hours and then passed through a 300-mesh sieve to obtain modified quartz powder.

[0055] Preparation of flame retardant powder:

[0056] S3.1. At room temperature, 10 parts by weight of barium carbonate were dispersed in 70 parts of deionized water to obtain a suspension A. 10 parts of phytic acid were dissolved in 65 parts of deionized water to obtain a phytic acid solution. The phytic acid solution and suspension A were mixed and stirred at 300 r / min for 5 h. After stirring, the mixture was filtered and washed with deionized water five times. The resulting solid was dried at 75°C for 12 h to obtain a barium phytate solid.

[0057] S3.2. Aluminum hydroxide and barium phytate solids in a mass ratio of 3:1 are stirred at a speed of 300 r / min for 20 minutes to obtain a mixture C, 20 parts of the mixture C are mixed with 20 parts of a lignin mixed liquid, wherein the lignin mixed liquid contains nano-lignin, ethanol and water in a mass ratio of 2:2:7, stirred at a speed of 300 r / min for 2 hours, dried at 80°C for 15 hours, and then ball-milled at a speed of 300 r / min for 1 hour to obtain the flame retardant powder.

[0058] Preparation of FRP cylinder:

[0059] S1. Cleaning and demoulding:

[0060] Clean the mold with acetone, dry it at 60°C for 24 hours, and evenly apply a layer of polyethylene wax release agent on the dry mold surface;

[0061] S2. Laying fiberglass mesh and closing the mold:

[0062] Lay the fiberglass mesh in the mold, roll it to remove air bubbles, and then close the mold together, making sure all edges and gaps are tightly fitted;

[0063] S3, mold preheating:

[0064] After checking the air tightness, preheat the mold and keep it at 80℃ for 1 hour;

[0065] S4. Rubber preparation:

[0066] The epoxy resin was preheated at 80°C for 30 minutes, and then epoxy resin: curing agent: flame retardant powder: filler with a mass ratio of 25:25:28:15 was stirred at a speed of 1000 r / min in a stirring kettle for 30 minutes, and a rubber compound was prepared by vacuum degassing.

[0067] S5. Vacuum casting:

[0068] The vacuum degree in the mold is reduced to -0.85MPa, and then the rubber material is introduced into the mold from the bottom, and poured from bottom to top until the rubber material fills the top outlet of the mold. Then the valve at the top outlet of the mold is closed, and the pressure of the mold filled with rubber material is increased to 0.6MPa at a rate of 0.1MPa / min. The valve is closed for 2 minutes, opened for 30 seconds, and the pressure is maintained for 10 minutes.

[0069] S6. Curing and demoulding:

[0070] The mold after step S5 is cured at high temperature, firstly the temperature is raised to 100°C and kept for 2 hours, then raised to 125°C and kept for 4 hours, and after complete curing, it is naturally cooled to room temperature, demoulded, and CNC trimmed to obtain the FRP cylinder A;

[0071] S7, post-processing:

[0072] The surface of the glass fiber reinforced plastic cylinder A after step S6 is sandblasted and epoxy resin paint sprayed to obtain the glass fiber reinforced plastic cylinder. The sand used in the sandblasting is quartz sand material with a particle size of 100 mesh and a processing pressure of 5.0 MPa.

[0073] Example 2

[0074] Preparation of filler:

[0075] S2.1. Mix quartz powder and aluminate coupling agent in a mass ratio of 30:1, ball mill at 300 r / min for 3 h, and pass through a 200-mesh sieve to obtain mixture A. Then, add anhydrous ethanol (7 times the mass of mixture A) and stir at 500 r / min at 43°C for 1.5 h. Heat to 110°C and dry for 12 h to obtain mixture B.

[0076] S2.2. A mixture of B, polyacrylamide and deionized water in a mass ratio of 10:1:25 was stirred at a constant speed for 1.5 h. The mixture was dried at 90°C for 12 h to obtain solid C. The solid C was ground at a speed of 300 r / min for 3 h and then passed through a 300-mesh sieve to obtain modified quartz powder.

[0077] Preparation of flame retardant powder:

[0078] S3.1. At room temperature, 13 parts of barium carbonate were dispersed in 80 parts of deionized water to obtain a suspension A, and 13 parts of phytic acid were dissolved in 65 parts of deionized water to obtain a phytic acid solution. The phytic acid solution and suspension A were mixed and stirred at 350 r / min for 5 h. After stirring, the mixture was filtered and washed with deionized water five times. The resulting solid was dried at 77°C for 15 h to obtain a barium phytate solid.

[0079] S3.2. Aluminum hydroxide and barium phytate solids in a mass ratio of 4:1 are stirred at a speed of 350 r / min for 25 minutes to obtain a mixture C, 20 parts of the mixture C are mixed with 23 parts of a lignin mixture, wherein the lignin mixture contains nano-lignin, ethanol and water in a mass ratio of 2:2:7, stirred at a speed of 350 r / min for 3 hours, dried at 87°C for 15 hours, and then ball-milled at a speed of 300 r / min for 1 hour to obtain the flame retardant powder.

[0080] Preparation of FRP cylinder:

[0081] S1. Cleaning and demoulding:

[0082] Clean the mold with acetone, dry it at 60°C for 24 hours, and evenly apply a layer of polyethylene wax release agent on the dry mold surface;

[0083] S2. Laying fiberglass mesh and closing the mold:

[0084] Lay the fiberglass mesh in the mold, roll it to remove air bubbles, and then close the mold together, making sure all edges and gaps are tightly fitted;

[0085] S3, mold preheating:

[0086] After checking the air tightness, preheat the mold and keep it at 90℃ for 1.5 hours;

[0087] S4. Rubber preparation:

[0088] The epoxy resin was preheated at 80° C. for 30 minutes, and then epoxy resin: curing agent: flame retardant powder: filler with a mass ratio of 27.5:27.5:30:15 was stirred in a stirred tank at a speed of 1000 r / min for 40 minutes, and a rubber compound was prepared by vacuum degassing.

[0089] S5. Vacuum casting:

[0090] The vacuum degree in the mold is reduced to -0.9 MPa, and then the rubber material is introduced into the mold from the bottom, and poured from bottom to top until the rubber material fills the top outlet of the mold. Then the valve at the top outlet of the mold is closed, and the pressure of the mold filled with rubber material is increased to 0.65 MPa at a rate of 0.1 MPa / min. The valve is closed for 2 minutes, opened for 30 seconds, and the pressure is maintained for 12 minutes.

[0091] S6. Curing and demoulding:

[0092] The mold after step S5 is cured at high temperature, firstly the temperature is raised to 100°C and kept for 2.5 hours, then the temperature is raised to 125°C and kept for 4.5 hours, and after complete curing, it is naturally cooled to room temperature, demoulded, and CNC trimmed to obtain the FRP cylinder A;

[0093] S7, post-processing:

[0094] The surface of the glass fiber reinforced plastic cylinder A after step S6 is sandblasted and epoxy resin paint sprayed to obtain the glass fiber reinforced plastic cylinder. The sand used in the sandblasting is quartz sand material with a particle size of 100 mesh and a processing pressure of 5.0 MPa.

[0095] Example 3

[0096] Preparation of filler:

[0097] S2.1. Mix quartz powder and aluminate coupling agent in a mass ratio of 30:1, ball mill at 300 r / min for 3 h, and pass through a 200-mesh sieve to obtain mixture A. Then, add anhydrous ethanol (7 times the mass of mixture A) and stir at 500 r / min for 2 h at 45°C. Heat to 120°C and dry for 12 h to obtain mixture B.

[0098] S2.2. A mixture of B, polyacrylamide and deionized water in a mass ratio of 10:1:25 was stirred at a constant speed for 2 h. The mixture was dried at 90°C for 12 h to obtain solid C. The solid C was ground at a speed of 300 r / min for 3 h and then passed through a 300-mesh sieve to obtain modified quartz powder.

[0099] Preparation of flame retardant powder:

[0100] S3.1. At room temperature, 15 parts of barium carbonate were dispersed in 90 parts of deionized water to obtain a suspension A, and 15 parts of phytic acid were dissolved in 65 parts of deionized water to obtain a phytic acid solution. The phytic acid solution and suspension A were mixed and stirred at 400 r / min for 5 h. After stirring, the mixture was filtered and washed with deionized water five times. The resulting solid was dried at 80°C for 17 h to obtain a barium phytate solid.

[0101] S3.2. Aluminum hydroxide and barium phytate solids in a mass ratio of 5:1 are stirred at a speed of 400 r / min for 30 minutes to obtain a mixture C, 20 parts of the mixture C are mixed with 25 parts of a lignin mixed liquid, wherein the lignin mixed liquid contains nano-lignin, ethanol and water in a mass ratio of 2:2:7, stirred at a speed of 400 r / min for 4 hours, dried at 95°C for 15 hours, and then ball-milled at a speed of 300 r / min for 1 hour to obtain the flame retardant powder.

[0102] Preparation of FRP cylinder:

[0103] S1. Cleaning and demoulding:

[0104] Clean the mold with acetone, dry it at 60°C for 24 hours, and evenly apply a layer of polyethylene wax release agent on the dry mold surface;

[0105] S2. Laying fiberglass mesh and closing the mold:

[0106] Lay the fiberglass mesh in the mold, roll it to remove air bubbles, and then close the mold together, making sure all edges and gaps are tightly fitted;

[0107] S3, mold preheating:

[0108] After checking the air tightness, preheat the mold and keep it at 100℃ for 2 hours;

[0109] S4. Rubber preparation:

[0110] The epoxy resin was preheated at 80° C. for 30 minutes, and then epoxy resin: curing agent: flame retardant powder: filler with a mass ratio of 30:30:32:15 was stirred in a stirred tank at a speed of 1000 r / min for 50 minutes, and a rubber compound was prepared by vacuum degassing.

[0111] S5. Vacuum casting:

[0112] The vacuum degree in the mold is reduced to -0.95 MPa, and then the rubber material is introduced into the mold from the bottom, pouring from bottom to top until the rubber material fills the top outlet of the mold. Then the valve at the top outlet of the mold is closed and the pressure of the mold filled with rubber material is increased to 0.7 MPa at a rate of 0.1 MPa / min. The valve is closed for 2 minutes, opened for 30 seconds, and the pressure is maintained for 15 minutes.

[0113] S6, curing and demoulding:

[0114] The mold after step S5 is cured at high temperature, firstly the temperature is raised to 100°C and kept for 3 hours, then raised to 125°C and kept for 5 hours, and after complete curing, it is naturally cooled to room temperature, demoulded, and CNC trimmed to obtain the FRP cylinder A;

[0115] S7, post-processing:

[0116] The surface of the glass fiber reinforced plastic cylinder A after step S6 is sandblasted and epoxy resin paint sprayed to obtain the glass fiber reinforced plastic cylinder. The sand used in the sandblasting is quartz sand material with a particle size of 100 mesh and a processing pressure of 5.0 MPa.

[0117] Comparative Example 1

[0118] The difference between Comparative Example 1 and Example 1 is that the quartz was not modified during the preparation of the filler in Comparative Example 1, and the other operations were the same.

[0119] Comparative Example 2

[0120] The difference between Comparative Example 2 and Example 1 is that barium phytate is not added during the preparation of the flame retardant powder in Comparative Example 2, and the other operations are the same.

[0121] Comparative Example 3

[0122] The difference between Comparative Example 3 and Example 1 is that no lignin was added during the preparation of the flame retardant powder in Comparative Example 3, and the other operations were the same.

[0123] Comparative Example 4

[0124] The difference between Comparative Example 4 and Example 1 is that in Comparative Example 4, the flame retardant powder is only aluminum hydroxide, and the other operations are the same.

[0125] Comparative Example 5

[0126] The difference between Comparative Example 5 and Example 1 is that in Comparative Example 5, vacuum casting is performed according to the conventional process: the vacuum degree in the mold is evacuated to -0.85 MPa, and then the rubber material is passed into the mold from top to bottom. After the mold is filled with the rubber material, the mold pressure is increased to 0.6 MPa and the pressure is maintained for 10 minutes.

[0127] Performance testing:

[0128] 1. Flame retardant performance: Refer to UL-94 "Standard for Flammability Tests of Plastic Materials for Equipment and Appliance Components", and the results are shown in Table 1:

[0129] Table 1

[0130]

[0131] 2. Axial bending strength: refer to GB / T 1449-2005, axial tensile strength and elastic modulus: refer to GB / T1447-2005, dielectric strength: refer to GB / T 1408.1-2016, dielectric parameters: refer to GB / T 1410-2006. The test results are shown in Table 2 below:

[0132] Table 2

[0133]

[0134] According to the above data, the glass fiber reinforced plastic cylinder prepared by the present invention has good flame retardancy and mechanical properties.

[0135] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A process for manufacturing a glass fiber reinforced plastic cylinder, characterized in that: The following steps are involved: S1. Cleaning and demoulding: Clean the mold with acetone, dry it at 60°C for 24 hours, and evenly apply a layer of polyethylene wax release agent on the dry mold surface; S2. Laying fiberglass mesh and closing the mold: Lay the fiberglass mesh in the mold, roll it to remove air bubbles, and then close the mold together, making sure all edges and gaps are tightly fitted; S3, mold preheating: After checking the air tightness, preheat the mold and keep it at 80~100℃ for 1~2h; S4. Rubber preparation: The epoxy resin was preheated at 80°C for 30 minutes, and then epoxy resin: curing agent: flame retardant powder: filler with a mass ratio of (25-30): (25-30): (28-32): 15 was stirred in a stirred tank at a speed of 1000 r / min for 30-50 minutes, and a rubber compound was prepared by vacuum degassing. S5. Vacuum casting: The vacuum degree in the mold is reduced to -0.85~-0.95MPa, and then the rubber material is introduced into the mold from the bottom, and poured from bottom to top until the rubber material fills the top outlet of the mold. Then the valve at the top outlet of the mold is closed, and the pressure of the mold filled with rubber material is increased to 0.6~0.7MPa at a pressure increase rate of 0.1MPa / min. The valve is closed for 2 minutes, opened for 30 seconds, and the pressure is maintained for 10~15 minutes. S6. Curing and demoulding: The mold after step S5 is cured at high temperature, and after complete curing, it is naturally cooled to room temperature, demoulded, and CNC trimmed to obtain the glass fiber reinforced plastic cylinder A; S7, post-processing: The surface of the glass fiber reinforced plastic cylinder A after step S6 is sandblasted and painted to obtain the glass fiber reinforced plastic cylinder; In step S4, the preparation process of the filler is as follows: S2.

1. Mix quartz powder and aluminate coupling agent in a mass ratio of 30:1, ball mill at 300 r / min for 3 h, and pass through a 200-mesh sieve to obtain mixture A. Then, add anhydrous ethanol (7 times the mass of mixture A) and stir at 500 r / min at 40-45°C for 1-2 h. Heat to 100-120°C and dry for 12 h to obtain mixture B. S2.

2. A mixture of B, polyacrylamide, and deionized water in a mass ratio of 10:1:25 was stirred at a constant speed for 1–2 h. After drying, solid C was obtained. Solid C was ground at 300 r / min for 3 h and then passed through a 300-mesh sieve to obtain modified quartz powder. In step S4, the flame retardant powder is prepared as follows: S3.1, in parts by weight, at room temperature, dispersing 10 to 15 parts of barium carbonate in 70 to 90 parts of deionized water to obtain a suspension A, then dissolving 10 to 15 parts of phytic acid in 65 parts of deionized water to obtain a phytic acid solution, mixing the phytic acid solution with the suspension A and stirring at a speed of 300 to 400 r / min for 5 h. After stirring, filtering, washing with deionized water, and drying the obtained solid to obtain a barium phytate solid; S3.

2. Aluminum hydroxide and barium phytate solids in a mass ratio of (3-5):1 are stirred at a speed of 300-400 r / min for 20-30 min to obtain a mixture C, 20 parts of the mixture C are mixed with 20-25 parts of the lignin mixed solution, stirred at a speed of 300-400 r / min for 2-4 h, dried at 80-95 ° C for 15 h, and then ball milled at a speed of 300 r / min for 1 h to obtain the flame retardant powder.

2. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S2, the glass fiber mesh is a twist-free reinforced mesh.

3. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S6, the process of curing at high temperature is: firstly raising the temperature to 100°C and keeping it for 2-3 hours, and then raising the temperature to 125°C and keeping it for 4-5 hours.

4. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S7, the sand used in the sand blasting process is quartz sand with a particle size of 100 mesh and a processing pressure of 5.0 MPa.

5. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S7, the paint is epoxy resin paint.

6. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S2.2, the drying condition is drying at 90° C. for 12 hours.

7. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S3.1, the drying condition is 75-80° C. for 12-17 hours.

8. The manufacturing process of the glass fiber reinforced plastic cylinder according to claim 1, characterized in that: In step S3.2, the lignin mixture contains nano-lignin, ethanol and water in a mass ratio of 2:2:7.

Images