Industry Information

What is the reason and improvement plan for the yellowing of large-diameter silicone tubing

  There are many reasons for yellowing, some are produced by the manufacturer during the production process, and some are yellowed during use. For example, most of the large-diameter silicone tubes of the corona machine are yellowed during use. In addition, the diaphragm of the silicone rubber aeration tube is yellowed . Yellowing is mostly caused by improper operation in the production process. Different types of yellowing reasons need to be improved by different methods.
  Yellowing is too fast during product use: Most of the yellowing reasons for this type of large-diameter silicone tube occur in dry, airtight, high temperature, outdoor, direct ultraviolet rays or chemical reactions, etc., and the yellowing speed in normal environments It is relatively slow and can be used for 1 to 5 years, so you can first determine whether your products are used in these environments.
  1. In a dry, non-ventilated and airtight environment, the yellowing of the large-diameter silicone tube should be improved because of the storage environment and the use environment. The silicone storage environment should be ventilated and kept in a cool place. Drying can be properly watered to maintain humidity or the temperature of the electric fan to keep the humidity of the silica gel relatively stable. The yellowing of the silica gel in the inventory indicates that the silica gel is being consumed at a high speed and needs to be paid close attention to. There are also some large-diameter silicone tubes that need to be assembled in a closed environment, such as sealed and assembled inside a product. In this case, yellowing is unavoidable, but it can be solved from the source. You can listen to the manufacturer's solution or replace it. For base materials or auxiliary materials, adding anti-yellowing agents during the production process can greatly reduce the yellowing.
  2. High temperature, outdoor yellowing: usually this kind of reason is because the product touches the performance limit of silica gel, for example, the use environment is high temperature resistant 200° and long-term temperature resistant, and the ordinary industrial grade large-diameter silicone tube (resistant to Temperature 200 ° upper limit) to use the silica gel has been overloaded, these are the important reasons for the accelerated yellowing of silica gel, the improvement method can be high temperature resistant rubber and ordinary rubber mixed with semi-vulcanized production, which can control the cost and achieve temperature resistance It can also reduce the speed of yellowing of silica gel and kill three birds with one stone. If you want to completely solve the yellowing caused by high temperature, you can directly replace it with high-temperature resistant silica gel. In addition, the outdoor yellowing is because the large-diameter silicone tube is directly exposed to the sun and experienced wind and rain, which leads to accelerated aging of physical factors. Secondly, the outdoor temperature drop is also relatively large, which is also one of the influencing factors. It is recommended to avoid long-term outdoor use or choose black. , yellow and other brighter colors to delay the yellowing speed or cover the yellowing color.
  3. Yellowing of the product in a chemical reaction or a slightly corrosive environment: If the large-diameter silicone tube needs to contact some slightly corrosive liquids or some chemical contacts, the silicone will also turn yellow and melt if it is severely yellowed. : Silica gel can not contact strong acid and alkali. The improvement method can be to use a new type of silica gel material (fluorine silica gel), which can be used in acid and alkali (the cost is more expensive). After solving the problem of acid and alkali, the yellowing of silica gel will naturally be solved.
  Another reason that can affect the yellowing of large-diameter silicone tubes is that problems have already occurred at the production end. Many customers' storage and use environments are suitable for silicone rubber, but the yellowing speed of the product is still relatively fast, which shows that the product itself There is already a problem.
  1. In the eyes of many manufacturers, the large-diameter silicone tube itself is a product that is not easy to produce. It is precisely because of this that the temperature of the silicone rubber increases during the extrusion process, resulting in high-temperature vulcanization and yellowing of the product. To put it bluntly, it is the vulcanization temperature. If it is too high, the silica gel will be directly baked yellow, and the vulcanization is divided into the front section and the back section. These two operations must be very precisely controlled to affect the yellowing of the silica gel, especially some inexperienced manufacturers are particularly prone to cause yellowing during the production process. The product turns yellow, because the wall thickness of the large-diameter silicone tube is often relatively thin, and the temperature in the drying tunnel needs to be readjusted, and this adjustment process directly affects whether the product turns yellow.
  2. The quality of the raw materials used is relatively low, and the silica gel raw materials are also divided into excellent, high, medium, and low. If some low-quality raw materials are used, the yellowing speed of the product will be affected to a certain extent, even in good condition. The yellowing speed will also be accelerated in the working environment, which is determined by the material itself.
  Most of the reasons for the yellowing of large-diameter silicone tubes are the following. It cannot be yellowing during use or during production. These can be solved by human beings, but it’s just whether you are willing to solve it. Silicone will eventually age and turn yellow. As long as the yellowing is within a reasonable range, it is normal aging and can not be investigated. If it is unreasonable yellowing, you need to prescribe the right medicine.
  With more than 20 years of production management experience, Dongguan Yutian is a silicone product manufacturer that only provides customers with high-quality services. If you need to customize your large-caliber silicone tube , please contact online customer service.