The fr4 epoxy board processing is a code for the grade of flame-resistant material, which represents a material sp...
The fr4 epoxy board processing is a code for the grade of flame-resistant material, which represents a material specification that the resin material must be able to extinguish itself after the burning state. Epoxy resins generally refer 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 active epoxy group in the molecular chain. The epoxy group can be located at the end, in the middle or in a cyclic structure of the molecular chain. Because the molecular structure contains active epoxy groups, they can undergo cross-linking reactions with various types of curing agents to form insoluble, insoluble polymers with a three-way network structure.
FR4 epoxy board processing has done very well in these aspects.
1. Diverse forms: various resins, curing agents, and modifier systems can almost adapt to the requirements of various applications on the form, and the range can be from extremely low viscosity to high melting point solids.
2. Convenient curing: Choose a variety of different curing agents, and the epoxy resin system can be cured at a temperature range of 0～180℃.
3. Strong adhesion: The existence of polar hydroxyl and ether bond inherent in the molecular chain of epoxy resin makes it have high adhesion to various substances. The shrinkage during curing is low and the internal stress generated is small, which also helps to improve the adhesion strength.
4. Low shrinkage: The reaction between epoxy resin and curing agent is carried out by direct addition reaction or ring-opening polymerization reaction of epoxy groups in the resin molecule, and no water or other volatile by-products are released. Compared with unsaturated polyester resins and phenolic resins, they show very low shrinkage (less than 2%) during curing.
5. Mechanical properties: The cured epoxy resin system has excellent mechanical properties.
6. Appearance: Appearance includes surface finish and color. There is no color regulation in current Chinese standards, that is, all colors are natural. And some national standards allow several prescribed colors, which are achieved by adding colorants. Because any colorant has a negative impact on the performance of the board, considering the specific application of the insulation board, natural color should be better; in the related production process, stainless steel materials are used to make light-colored products, such as When using ordinary carbon steel equipment, the color of the product becomes darker; in addition, the color will become darker with the extension of storage time, so the color of the plate seen in different occasions is diverse.