Silicone in National defense

The use of adhesives has a long history. As early as 4,000 years ago, raw lacquer was used as adhesives in my country, and it was also used in military industry. In ancient weapons, both China and Japan used bone glue to connect armor and scabbard. During the Second World War, due to the needs of the military industry, adhesives also underwent corresponding changes and developments, especially for aircraft structural parts, and a new name of structural adhesives appeared.

In 1941, the British Aero company invented a phenolic-polyvinyl acetal resin hybrid structural adhesive, which was successfully used in the connection of fighter main wings in July 1944. Later, it was applied to the manufacture of "Comet" aircraft. Today, bonding technology is widely used in daily life and various industries, and has become an indispensable technology in modern military fields such as aviation, aerospace, shipbuilding and electronics.

With the development of science and technology in the military field, there are new requirements for the performance of adhesives. For example, adhesives used in military electronics need to have functions such as electrical conductivity, thermal conductivity, waterproof, and shock absorption. Various parts of launch vehicles, satellites, spaceships, and aircraft carriers often require adhesives with electrical conductivity, magnetic conductivity, high temperature resistance, low temperature resistance, and space environment resistance due to their special application conditions.

In the manufacture of military electronic equipment, bonding technology is widely used, such as sticking instead of welding, sticking instead of riveting, sticking instead of screw connection and sticking instead of tight fit, etc., to simplify the process, reduce the cost, shorten the production cycle, and improve the production efficiency. Realize functional requirements such as reinforcement, sealing, insulation, thermal conduction, electrical conduction, marking and decoration of the whole machine and components. In addition to mechanical connection and fixation, the use of adhesives in military electronic equipment also has special requirements, such as thermal conductivity, electrical conductivity, insulation, shock absorption, sealing and protection, etc., and has the ability to adapt to various The ability of harsh environments, such as anti-salt spray, anti-mold and anti-humid heat, etc. According to different materials, use environment, special requirements of equipment, etc., choose different adhesives.

Pressure-sensitive adhesives are a type of adhesives that are sensitive to pressure. According to the composition of the main resin, they can be divided into two types: rubber type and resin type. It has a wide range of applications and can be used in diapers, women's products, double-sided tapes, labels, packaging, medical and health care, book binding, surface protection films, wood processing, wallpaper and shoemaking, etc. In the field of military electronics, it is mainly used for the bonding of light structural parts such as metal nameplates, decorative strips and insulating gaskets.

Silicone adhesive has unique heat resistance, low temperature resistance, good electrical insulation performance and weather resistance, chemical stability, hydrophobic moisture resistance, oxidation resistance, sealability and other characteristics. Silica gel is used as the basic raw material, and various auxiliary materials such as thermal conductive metal oxides, conductive metal powders, and additives are added. After special processing, it can be made into thermal conductive silica gel and conductive silica gel. Silicone sealants are mainly used for the bonding of rubber sealing rings in the field of military electronics, which has good sealing and waterproof performance; it is used to reinforce components such as resistors and capacitors on printed boards, and has the functions of fixing and shock absorption effect. Thermally conductive silicone has high bonding performance and super heat conduction effect, which is currently the best heat conduction solution when CPU, GPU and heat sink are in contact.

Epoxy conductive adhesive is to add silver powder, copper powder, carbon black and other conductive fillers to the general epoxy adhesive. After curing, it has certain conductivity and good bonding performance, so that the bonded materials can directly form an electrical path. Epoxy conductive adhesive is often used for the installation of chips and light-emitting diodes and the bonding of high-power resistors and aluminum heat sinks; epoxy conductive adhesive can be used to bond circuit components and substrates instead of eutectic welding, which can avoid the adverse effects of high heat ;Epoxy conductive adhesive can be used to bond SMD (surface mount components) to the circuit; for metal shells that require shielding against electromagnetic interference, epoxy conductive adhesive can be used to bond and ground.