Important materials for dioma silicon oil -automotive electronic component!(2)

Thirty years ago, when organic silicon materials were used for electronic applications for the first time, one of its most useful properties was to stabilize the dielectric performance at a wide range of temperature and frequency range. Organic silicon polymers are very small with the force between the molecular molecule (even under a wide temperature fluctuations), so the physical and electrical properties are very stable.

Another important factor in improving component reliability is wet resistance. Organic silicon hate means that they are not easy to absorb water molecules. At the same time, high gas permeability allows moisture to spread quickly, thereby eliminating potential corrosion sources. In addition, PDMS (polymailing silicone) very low surface tension and excellent wetting characteristics, as well as the adhesion characteristics obtained through advanced viscosity enhancers to help achieve gap bonding, thereby further improving the overall reliability as a whole Essence

Because elastic materials can help reduce the effects of vibration and absorb the differences in thermal expansion of sensitive components and substrates, low modulus is also important for minimizing the stress of electronic components. In the typical operating temperature range of the automotive electronics, the current silicon formula does not show the glass temperature (TG), so the modulus remains quite constant in this cycle. This manifestation is obviously different from elastic epoxy resin for electronics. The amount of elastic epoxy resin adds more than three levels between the extreme high and low temperature often encountered by automobile applications. CICS silicon is chemical inertia and extremely stable. Many products operate in the temperature in the temperature of 250 ° C (-50 ° C ~+200 ° C), which can also maintain its physical properties. This makes organic silicon one of the chemical materials that can withstand the harsh environment (the harsh environment that must work in automotive electronic components).

Application of polymailing siliconane

Classified according to the use of organic silicon applications, mainly divided into the following three categories: ① adhesive/sealing agent ② irrigation agent ③ insulation gel. Their main ingredients are silicone, that is, di meta silicon oil, molecular formula: (CH3 CH3 ) 3SIO (CH3) 2sionSi (CH3) 3, a polymer of organic silicon oxides, is a series of polymethyl siliconane with different molecular weights. The viscosity increases with the increase in molecular weight.

01

The adhesive/sealing agent is mainly used to bond components in the electronic module, or to pack the shell to isolate dust, water or other impurities. The main advantage of organic silicon adhesive is that it has the potential to improve reliability through unique elasticity and stress. When components and circuit boards are contracted by fast thermal circulation, elastic organic silicon binders help absorb thermal expansion and avoid stress transmitted from rigid binders to components. Their unique heat stability allows them to be elastic under extreme temperature and repeated heat shock.

When there is a heat dissipation problem, the use of heat -conducting fillers can significantly enhance the thermal conductivity of organic silicon binders. The design of thermal organic silicon adhesive is used to help eliminate the calories of components and circuits, so that the higher reliability and longer life of the engine cabin device under high temperature conditions.

In automotive electronics applications, it is better to use good tight and sticky materials. The adhesive performance maintains its performance unchanged for a long time in a variety of use environments. Due to its low -modular amount after curing, the organic silicon bonding agent can effectively eliminate thermal stress and mechanical stress, thereby significantly enhanced reliability and service life.

02

The sealing agent is a protective material designed to completely implant electronic components and circuits. They are particularly used to isolate the circuit from the very harsh use of the environment and provide high -voltage insulation for high -voltage circuits to protect the effects of the connector from heat and mechanical stress. Organic silicon sealing agents are usually used for thick layers.

More and more organic silicon -sealing agents have the ability to adhere to them. When curing heating to 100 ° C, they can bond well with many commonly used substrates. Other materials need to be sprayed first to get fully bonding. Tests (or acceleration testing) under actual use conditions are critical for predicting long -term performance in any application.

Just like most organic silicon products, the irrigation agent can also provide a variety of options. They have high shear strength, clear optics, flame retardant or extreme low temperature performance. Specific materials provide heat or volatility, while other materials are used to meet the UL specifications.

03

Insulation gel is a special -level irrigation agent, which can solidify extremely soft materials with good buffer, elasticity and self -repairing properties. The colloid provides the best way to relieve thermal stress and mechanical stress, while maintaining stable flexible body volume. They are particularly used for thick layers to completely seal and dense architecture, especially high -density lead. Special materials are used to improve performance, such as high -light penetration, solvent resistance and oil resistance, low volatility or flame retardability.

Future trend

Organic binders and protection materials used by many automotive electronics markets cannot withstand higher calories caused by new design. Higher reliability requirements also exceed the product limit of traditional production components and circuit boards. The higher temperature will also exacerbate the non -matching of the thermal expansion coefficient (CTE), which increases the stress on the surface of the component, leading to bending, physical damage and premature failure.

In the current and new car design, higher temperatures and increased electronic component power (especially in electromechanical applications or HEV (mixed electrical vehicles) control units) in the engine compartment all cause higher heat resistance. In addition, optical and clear silicon is quickly entering the automotive market, which is increasingly reflected in: they are key factor for the stability protection of light -emitting diode and forming optical instruments and optical sensors.

Due to physical and extensive commercial processing properties, organic silicon will soon become a launcher for automotive electronics. By improving the performance of electronics, optical circuits, and components, and reducing its failure, the design of organic silicon materials is used to meet the safe, lighter, and higher -performance component demand for the automotive industry. Application in the environment.