The latest technology for preparing silicon carbide composite non-woven fabrics—new technology of solution jet spinning

The composite non-woven fabric has always been an advanced technology product of the non-woven fabric technology in a new form. Nowadays, more and more products use composite non-woven fabrics to assemble products, and have achieved good results. Today, I will lead you to learn more about the latest solution jet spinning technology of silicon carbide composite non-woven fabrics. cloth. At present, the domestic production of a small amount of silicon carbide (SiC) composite non-woven fabrics mainly uses continuous melt blown technology. I personally think that although meltblown technology is very promising in the industry, the limitations of the technology are also obvious. It is well known that some polymers, such as polyacrylonitrile, have decomposed before being melted and cannot be melted. At the same time, some polymers, such as polytetrafluoroethylene, cannot be processed by melt spinning due to their high melt viscosity and extremely high melting point. Therefore, the continuous melt blown process used to prepare silicon carbide composite non-woven fabrics still has certain defects. The solution jet spinning method uses a peristaltic pump to squeeze out the spinning liquid. Under the jet of high-speed airflow, the trickle is extremely stretched to form a very fine micron composite non-woven fabric, which has a wider range than electrostatic spinning. Application range. In addition, compared with electrospinning technology, solution jet spinning has a major advantage, that is, the spinning speed is fast, and more micron fiber nonwovens can be obtained in a short time, which is expected to make silicon carbide composite nonwovens Large-scale industrialization has become a possibility. The preparation of silicon carbide composite non-woven fabrics by solution jet spinning is a new non-woven spinning technology, which has certain points in common with electrospinning: both use polymer solutions to prepare micron fiber surfaces, but they are different In the electrostatic spinning technology, the solution jet spinning method uses a peristaltic pump to squeeze out the spinning liquid. Under the jet of high-speed airflow, the trickle is extremely stretched to form a very fine micron composite non-woven fabric. At the same time, different spinning conditions are adopted according to the different spinning solutions, such as temperature, wind pressure, flow rate, receiving distance, etc., so that it is suitable for most spinning solutions. This method is used to prepare ultrafine fibers, so it has more advantages than electrostatic spinning. A wide range of applications. Moreover, compared with electrospinning technology, solution jet spinning has a major advantage, that is, the spinning speed is fast, and more micron fiber non-woven fabrics can be obtained in a short time, making the silicon carbide composite non-woven fabrics large-scale Industrialization becomes a possibility. Researchers from the Department of Materials Science and Engineering at Imperial College London believe that the spinning solution must be very cautious when selecting solvents and meet the following points: First, the boiling point cannot be too low or too high, usually the boiling point of the solvent is 50 ℃ ~ 160 ℃ is the best range. If the boiling point is too low, it will cause waste due to volatilization and pollute the air; if the boiling point is too high, it is inconvenient to recycle; second, the solvent needs to have sufficient thermal and chemical stability. It is not easy to decompose in the process; the third is that the solvent is required to be low in toxicity and less corrosive to the equipment; the fourth is that the solvent does not cause damage to the polymer or other chemical changes in the process of dissolving the polymer; the fifth is that the temperature is appropriate The solvent should have good dissolving ability and still have the highest possible viscosity at a higher concentration. In fact, in addition to this method, the formation of silicon carbide (SiC) composite non-woven fabrics also includes melt spinning and solution spinning. The solution jet spinning technology can be directly produced from polymers due to the use of high-speed heating airflow. It is made into a composite non-woven fabric and can obtain a sub-micron fiber surface, which has attracted the attention of foreign scientists.