With the continuous development of science and technology, continuous fiber thermoplastic composites, as high-performance composite materials, have been widely used in aerospace, automobile, sports equipment and other fields. In this paper, we will introduce the main preparation technologies of continuous fiber thermoplastic composites, including melt impregnation method, pultrusion molding method, 3D printing technology and film reinforcement technology.
Melt impregnation is a common method for the preparation of continuous fiber thermoplastic composites. The method is to melt the thermoplastic resin, impregnate the fiber-reinforced material, and then cure it under pressure. The advantages of the melt impregnation method are simple process, low cost, high production efficiency, and suitable for large-scale production. However, this method also has some disadvantages, such as uneven resin impregnation and low fiber volume content. In order to solve these problems, researchers have developed a variety of improved melt impregnation methods, such as pre-impregnation, multi-step impregnation, etc.
Pultrusion is a method used to prepare continuous fiber thermoplastic composites by continuous extrusion. In this method, the fiber-reinforced material and the thermoplastic resin are passed through the die at the same time, melted and impregnated in the mold cavity, and the profile is continuously extruded. The advantages of pultrusion molding are high dimensional accuracy, high fiber content, and excellent mechanical properties. However, this method also has some disadvantages, such as low production efficiency, high mold cost, single product shape, etc.
3D printing technology is a rapid prototyping technology based on digital model files. In the preparation of continuous fiber thermoplastic composites, 3D printing technology can be used to manufacture parts with complex shapes and internal structures. In this method, thermoplastic resin powder is used as raw material to construct a three-dimensional solid by stacking layer by layer. The advantages of 3D printing technology are high manufacturing precision, strong customization, and high material utilization. However, this method also has some disadvantages, such as high cost and low production efficiency.
Film reinforcement technology is a method that utilizes a thermoplastic resin film as a reinforcement material. In this method, the resin film is bonded to a fiber-reinforced material, which is melted and impregnated by heating and pressurized to form a continuous fiber thermoplastic composite. The advantages of thin-film reinforcement technology are the simplicity of the fabrication process, the low cost, and the suitability of large areas or complex parts. However, this method also has some disadvantages, such as uneven resin impregnation and low mechanical properties.
In addition to the above preparation techniques, there are some other technologies that can be used for the preparation of continuous fiber thermoplastic composites, such as electrostatic spraying, vacuum hot pressing, etc. Each of these techniques has its own advantages and disadvantages, and the appropriate preparation technology can be selected according to the specific application needs.
In conclusion, there are various preparation techniques for continuous fiber thermoplastic composites, and different preparation technologies have different advantages, disadvantages and scope of application. In order to obtain high-performance composites, it is necessary to select the appropriate preparation technology and optimize its process parameters. At the same time, future research should also focus on the development of new fabrication technologies and processes to further improve the performance and cost reduction of continuous fiber thermoplastic composites, and provide strong support for the rapid development of various industries.