Effect of sizing agent on the interfacial adhesion of carbon fiber-reinforced polyamide 6 composites

In this paper, polyurethane sizing agents adapted in thermoplastic matrix polyamide 6 were prepared. The morphology and microstructure of unsized and sized carbon fibers were characterized by scanning electron microscopy and atomic force microscope. To observe the functional groups of sized carbon fibers, infrared spectra and X-ray photoelectron spectra were performed. Transverse fiber bundle (TFB) test was used to determine interfacial adhesion between carbon fiber and matrix. The results show polyurethane polymer was successfully coated on carbon fiber surface. Sizing remarkably improved interfacial adhesion between carbon fiber and polyamide 6.