FRP pultrusion is the mainstream technology in composite materials production currently. It was introduced into China at the end of the last century from Europe and the United States, and it has the rapid popularization and application. China has become the world’s main FRP pultruded product production country. In China, the most commonly used material for FRP products is unsaturated polyester resin, vinyl ester. In recent years, some areas began to use epoxy resin, phenolic resin is also used in pultrusion process, and has got a good effect and good economic benefit. Today we specifically talk about the special requirements of the production process of phenolic resin to pultrusion mold.
In FRP pultrusion process production, we use reinforced material roving, it goes through the mold from the roving shelf. When pultruding, first through hot molding glass fiber with the same size of FRP pultrusion mold, and then enter the FRP pultrusion equipment. Between the yarn frame and mold, with a dipping tank, wherein the placed resin mixture prepared by impregnating resin, fiber mixture after mold preforming device for distribution, then enter the thermosetting molding. In the unsaturated polyester resin pultrusion process, due to the use of active diluent styrene, which itself can play the role of cross-linking agent, thus the pultrusion die inside won’t produce volatile substances in glass steel. Phenolic resin and today we tell about a polycondensation resin, chemical reaction chain growth or crosslinking process at high temperature, will produce water molecules. Because of the FRP pultruded mold cavity temperature often at 100 DEG C, and phenolic resin curing process, the water vapor to discharge, which is phenolic pultrusion technology key problems need to be solved. Secondly, as the resin mixed acid catalyst material of microporous chromium plating layer by the erosion of FRP pultrusion mold, thus affecting the mold cavity and the mold service life, greatly increasing the cost of production. It is also one of the reasons why we need to pay special attention to the phenolic resin pultrusion process.
