Application requirements for epoxy potting compound

Potting is an important application field of epoxy resin. It has been widely used in the electronic device manufacturing industry and is an indispensable and important insulation material in the electronic industry. Sealing is the process of mechanically or manually filling liquid epoxy resin composites into devices containing electronic components and circuits, and curing them under normal temperature or heating conditions to become high-performance thermosetting polymer insulation materials. Its function is to strengthen the integrity of electronic devices and improve their resistance to external impacts and vibrations; Improving the insulation between internal components and circuits is beneficial for device miniaturization and lightweighting; Avoiding direct exposure of components and circuits, and improving the waterproofing and moisture-proof performance of devices.

Epoxy potting compound has a wide range of applications, diverse technical requirements, and a wide variety. There are two types of curing conditions: room temperature curing and heating curing. There are two types of formulations: dual component and single component. Multi-component dosage forms are not commonly seen as commodities due to their inconvenient use. Room temperature cured epoxy potting compound is generally a two-component material that can be cured without heating after sealing. It does not require high equipment requirements and is easy to use. The disadvantage is that the composite material has a high viscosity, poor infiltration, short applicability, and is difficult to achieve automated production. In addition, the heat resistance and electrical performance of the cured material are not very high. It is generally used for sealing low-voltage electronic devices or in situations where heating and curing are not suitable.

The heating-cured two-component epoxy sealing adhesive is the most widely used and widely used variety. Its characteristics are low viscosity in composite operations, good processability, long applicability, good infiltration, and excellent comprehensive performance of cured materials. It is suitable for the use of single-component epoxy sealing materials in automatic production lines of high-voltage electronic devices. It is a new variety developed abroad in recent years and requires heating and curing. Compared with a two-component heating-cured sealing adhesive, the outstanding advantage is that the required sealing equipment is simple and easy to use, and the quality of the sealing adhesive depends less on the equipment and process. In addition to the shortcomings, the cost is relatively high and the material storage conditions are strict. The epoxy sealing adhesive used should meet the following requirements:
1. Good performance, long applicability, suitable for large-scale automatic production line operations.
2. It has low viscosity, strong infiltration ability, and can fill the components and wires.
During the sealing and curing process, the powder components such as fillers settle less and do not layer.
4. The curing exothermic peak is low, and the curing shrinkage is small.
5. The cured material has excellent electrical and mechanical properties, good heat resistance, good adhesion to various materials, low water absorption and linear expansion coefficient
6. In certain situations, it is also required that the sealing material has properties such as flame retardancy, weather resistance, thermal conductivity, and resistance to high and low-temperature fluctuations.