Deformation behavior at interface between glass fiber and polypropylene

A fiber-reinforced polymer material often uses a thermosetting polymer material as a matrix, but the use of a thermoplastic polymer material could widen the use of fiber-reinforced polymer material into various fields because of its higher moldability. This paper has two aims: 1) to investigate the interfacial properties of the fiber and the matrix for exploring better physical properties; and 2) to summarize the influence of the properties on the interfacial adhesive strength. In this study, the deformation behavior near the glass fiber / polypropylene interface was observed. First, as a development of a test piece manufacturing device, a vacuum forming device was prototyped. Next, fiber reinforced plastic (FRP) was manufactured to investigate the relationship between the molding of spherulites and transcrystalline layers and the molding conditions. The results showed that the transcrystalline layer could be formed by applying a shearing force to the fibers at the crystallization temperature after melting at a high temperature. Using the test pieces manufactured by the device, a tensile experiment of spherulite and transcrystalline was carried out, and it was found that the formation of the transcrystalline layer enhanced the interfacial adhesive strength.