Polyurethane filling Sealing glue, also known as PUPotting glue, usually made ofPolyols and diisocyanates of oligomers such as polyester, polyether and polydiene, with 二yuan Alcohol or diamine is a chain extender, which is formed through step-by-step polymerization . Polyurethane potting glue isdifferenceA potting glue between epoxy resin glue and silicone, with a hardness slightly lower than that of epoxy resin , higher than organic silicon, up to 50-70 A.
Polyurethane potting glue is characterized by low hardness, moderate strength, good elasticity, water resistance, mildew resistance, impact resistance, transparency, excellent electrical insulation and flame retardancy, and is good for electrical components Non-corrosive, good adhesion to steel, aluminum, copper, tin and rubber, plastic, wood and other materials. Polyurethane potting compounds protect installed and commissioned electronic components and circuits from vibration, corrosion, moisture and dust.
The application advantages of polyurethane potting adhesive products:
Polyurethane potting The glue has good waterproof and acid resistance. Generally, equipment that needs to be soaked in deep water for a long time is packed with polyurethane. Polyurethane potting glue has good flexibility and impact resistance, and can quickly recover after deformation, which is between potting silicone and epoxy resin.
Polyurethane potting adhesive product application disadvantages:
Polyurethane filling The obvious disadvantage of sealant is that it is more prone to bubbles than silicone and epoxy glue. Sometimes the bubbles are small and dense, which is very unsightly and requires vacuuming and glue filling, which is a complicated operation. For some products with strict appearance requirements, polyurethane potting glue may not be a good choice.
Polyurethane potting glue operation method:
1. Preheat: The poured device is placed in an oven at about 60°C for 1-2 hours to remove moisture from the device.
2. Mixing: Weigh a certain amount of material A, then add material B in proportion, and stir evenly in a mixing container.
3. Degassing: Vacuum degas the mixture (Note: A small amount of bubbles remaining on the surface of the glue before stopping vacuuming is normal and will disappear naturally under normal pressure).
4. Pouring: Pour the degassed mixture into the device to be poured. It can be completely solidified at 23℃/3-4 hours.