Epoxy resin adhesive-epoxy curing agent
Epoxy resins are thermoplastic linear resins. Only after the epoxy curing agent is added, the three-dimensional network structure can be formed to reflect its unique properties, and then it can be applied. Among the curing agent products, the anhydride curing agent occupies an important position and is one of the varieties with a large amount of curing agent in the market and widely used. The epoxy resin and acid anhydride curing agent, etc. can be heated to form various forms of thermosetting adducts through various processing techniques. The characteristics of the acid anhydride system curing agent are small shrinkage, no by-products, good heat resistance, good sealing, good insulation, and large selectivity of various additives. It can be used in the fields of electronic potting, electrical appliance casting, encapsulation, pultrusion, winding, laminated insulating materials and composite materials, powder coatings, etc.
1. Electronic potting Electronic potting products range from small electronic components, precision instruments, military communications products, and various electronic casting products to large transformers, from motor coils to current transformers in high-voltage appliances, cable junction boxes and cable terminals, etc. Class curing agents are widely used.
2. During pultrusion products, continuous glass fiber bundles, belts or cloths impregnated with resin glue are continuously produced under the action of traction force to continuously produce glass fiber reinforced plastic profiles with unlimited length. This process is suitable for the production of glass fiber reinforced plastic profiles of various cross-sectional shapes, such as rods, tubes, I-shaped, grooved, square profiles and hollow profiles. In the production of pultruded products, the curing agent of epoxy resin system generally adopts anhydride curing agent. Although unsaturated resin pultrusion is also used, its comprehensive performance, especially in mechanical properties, insulation properties, and shrinkage, is not as good as epoxy resin pultrusion products.
3. Laminated products Epoxy laminated products are glue solutions made of fiber fabric reinforced materials impregnated with epoxy resins / curing agents, etc., which are dried at a certain temperature to obtain prepregs. The prepregs are cut and laminated, and then cured by hot pressing It is formed into a plate, which is heated and solidified into a tube and a tube by winding. Laminated products use epoxy resin systems, mainly using anhydride curing agents, amine curing agents using dicyandiamide and aromatic amines, and synthetic resins are also used as curing agents. Epoxy copper-clad laminate is the basic material of the electronics industry, used to manufacture printed circuit boards, and is widely used in electronic computers, communication equipment, instrumentation equipment, household appliances and so on.
4. Winding products Winding products are the continuous fibers (cloth, pre-impregnated yarn) impregnated with resin are wound onto the core mold according to a certain rule, and then cured and demolded to obtain products of a certain shape. The most representative of the winding products is the epoxy curing system with long service life, low viscosity, low calorific value and low toxicity. Therefore, liquid acid anhydride is generally used as the main choice.
5. Moulded plastic products Moulded plastic is mainly used to encapsulate small electronic components such as transistors, integrated circuits, capacitors, resistors, etc. Its advantages are easy operation, high production efficiency, and more fillers can be used. It uses both curing agents for anhydrides and amines.
6. Vacuum pressure dipping products In the production of vacuum pressure dipping products, the glass cloth is first wound on the mandrel shaft and put into the mold, then the epoxy adhesive is sucked into the mold cavity under vacuum, and then The tube can be obtained by gel curing under a certain pressure and temperature. The production process mainly uses liquid anhydride curing agent.
7. Epoxy resin coating Epoxy resin mainly uses its excellent adhesion and excellent chemical resistance in the coating process. It has a wide range of applications in the fields of corrosion prevention, electrical insulation, transportation, civil engineering and other fields. The main applications of anhydride curing agents in epoxy resin coatings are dripping paint, powder mica tape insulation paint, powder coating, etc. Among the acid anhydride curing agents, liquid acid anhydrides are the most widely used in the market because of their convenient operation process and ultra-high cost performance.