A high‐performance carbon fiber/PET thermoplastic composite laminates based on matrix‐interface integrated strategy and chopped ultra‐thin carbon fiber tapes technology

Abstract Carbon fiber (CF) reinforced thermoplastic composites exhibit the advantages of excellent damage tolerance, impact toughness, and recyclability. However, the high viscosity of the thermoplastic resin such as polyethylene terephthalate (PET) and the surface inertness of CF result in defects and limit the mechanical properties. Based on a matrix‐interface integrated strategy, the chopped ultra‐thin (CUT) CF/PET tapes prepared by mechanical spreading and the PET solution infiltrating method enhance the permeation of the thermoplastic resin into CF tows. Fiber spreading shortens the distance for the resin to impregnate into the CF tows, which helps to reduce the porosity of the composites. Moreover, the PET sizing agent constructs matrix‐interfacial integrated composites and facilitates interfacial bonding. The optimal tensile strength, Young's modulus, flexural strength, flexural modulus, impact strength, and porosity of the quasi‐isotropic CUT‐CF/PET tapes reinforced PET composites are 637.6 MPa, 23.0 GPa, 494.7 MPa, 49.2 GPa, 122.3 kJ/m², and 5.49%, respectively. X‐ray micro computed tomography confirmed the low porosity and in‐plane quasi‐isotropic distribution of CUT‐CF tapes. This work provides a new path for short‐cut CF reinforced thermoplastic composites. Highlights An ultra‐thin carbon fiber/thermoplastic resin tape is proposed Matrix‐interface integrated strategy improves interfacial bonding Chopped ultra‐thin fiber tape achieves quasi‐isotropic and excellent mechanical properties.