The price of silicone electronic potting glue in the market is high and low, and the price of some electronic potting glue is far lower than the average market price. Why? Is their technology advanced and can effectively control production costs? In fact, the reason is that they add low-cost white oil to the potting compound material, which controls costs and disrupts the market.
What is white oil?
White oil, also called white mineral oil, is a special deep-refined mineral oil. Transparent, colorless, odorless, chemically inert, the basic substances are saturated hydrocarbons, aromatic hydrocarbons, etc., and the molecular weight is usually between 250 and 450. The boiling point is generally within 150 °C. It is widely used in daily chemical, pharmaceutical, food, rubber and plastic, agriculture and other industries.
Why does adding white oil reduce production costs?
Because the price of white oil is relatively low. For example, the general market price of silicone oil is 30 yuan/kg, while the price of white oil is only 10 yuan/kg. On the premise of ensuring the acceptance quality of electronic potting glue, 20% white oil can be added, then doping The glue cost of white oil is 26 yuan/kg. In this way, by adding an appropriate proportion of white oil, the price of electronic potting glue can be reduced and the potting glue market can be seized.
What is the effect of electronic potting compounds with added white oil?
We know that silicone oil is a polymer material with a siloxane structure and has organic and inorganic properties, while white oil is an organic polymer with a carbon structure and has no inorganic properties. Since white oil is chemically inert, it does not participate in the cross-linking reaction of organic silica gel.
When the silicone is cured, the free white oil slowly seeps out of the glue. Once the electronic potting compound doped with white oil is used on electronic products such as driving power supply, the following situations may occur:
- Various physical properties are poor, such as tensile strength and tear strength will decrease;
- The ability of heat dissipation and flame retardancy is poor, and it is difficult to effectively improve the heat dissipation capacity and safety factor of electronic products, which is prone to accidents;
- Poor high and low temperature resistance, poor weather resistance, and easy cracking of the colloid, allowing rainwater to penetrate into the electronic components from the cracks, reducing the moisture-proof ability of electronic products, and causing electronic components to fail;
- The electrical performance and insulation ability are poor, which affects the anti-electromagnetic interference ability of electronic components after potting, and is prone to failure.
How to detect whether white oil is added to electronic potting compound?
Since the boiling point of white oil is relatively low, less than 150 °C, and the boiling point of silicone oil is around 200 °C, the simple method in the laboratory is to test the volatile content of the uncured or cured potting compound. The test method is: oven at 150 °C After baking for 3 hours, the weight difference after volatilization was measured. The volatile matter of normal electronic potting glue is less than 1%, and the volatile matter of added white oil is greater than 5%. When the volatile content is abnormally high, it can be judged that white oil is added to the electronic potting compound.
In short, when we choose electronic potting glue, we can’t blindly covet cheap prices, we must consider the comprehensive selection of product quality and company services.