Insulation sheet refers to organic polymer compounds containing two or more epoxy groups in the molecule. Except for a few, their relative molecular mass is not high. The molecular structure of epoxy resin is characterized by the presence of active epoxy groups in the molecular chain. The epoxy groups can be located at the end, middle or ring structure of the molecular chain. Because of the active epoxy groups in the molecular structure, they can undergo cross-linking reactions with various types of curing agents to form insoluble, infusible polymers with a three-dimensional network structure.
Characteristics of insulation sheet :
1. Diverse forms. Various resins, curing agents, and modifier systems can almost meet the requirements of various applications for the form, ranging from extremely low viscosity to high melting point solids.
2. Convenient curing. By selecting various curing agents, the epoxy resin system can be cured almost within the temperature range of 0 to 180°C.
3. Strong adhesion. The presence of polar hydroxyl groups and ether bonds inherent in the epoxy resin molecular chain makes it have high adhesion to various substances. The epoxy resin has low shrinkage during curing and produces small internal stress, which also helps to improve the adhesion strength.
4. Low shrinkage. The reaction between epoxy resin and the curing agent used is carried out by direct addition reaction or ring-opening polymerization of epoxy groups in the resin molecule, without the release of water or other volatile by-products. Compared with unsaturated polyester resins and phenolic resins, they show very low shrinkage (less than 2%) during the curing process.
5. Mechanical properties. The cured epoxy resin system has excellent mechanical properties.
