Long-fiber prepreg

LFP long-fiber prepreg LPIM low-pressure injection molding... 

Global Energy Concepts of Dayton, OH, USA is using carbon fiber prepreg for large wind blades for the Vestas 90 m long blade. This... 

Compression molding is a highly nonisothermal process. In the processing of blanks consisting of a thermoplastic reinforced with long fibers, the blanks are preheated and then placed in the mold, which is at a temperature lower than that of the blanks. In the case of thermoplastic prepregs, the... 

A matched set of tapered rectangular winding mandrels for the spars was designed from glass fiber, based on the similarity of its linear coefficient of thermal expansion (GTE) characteristics with the GTE characteristics of carbon. One kit of five mandrels was fabricated for the vertical stabilizer, and a second kit of four mandrels was made for the horizontal stabilizer. For the small, square tubing used as core, a cable braider was used to wind prepreg tape over long, hollow mandrels made with extruded PVG and silicon rubber. 

Obviously, if spherulite boundaries are areas of weakness, then the occurrence of transcrystallinity must raise doubts. Although transcrystallinity enhances the physical bond between fiber and matrix, in prepregs with a high fiber content, where the fibers are in close proximity, adjacent transcrystalline regions may impinge and the boundary between transcrystalline regions and could act as a long spherulite boundary. 

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