Preparation of Self‐Reinforced Polypropylene Composites via Infrared Radiation Preheating

ABSTRACT Previous studies implemented a hot‐pressing protocol to optimize the processing parameters and composition for producing high‐performance self‐reinforced polypropylene (SRPP) composites, yet the methodology still necessitates further refinement. This study systematically investigates the influence of infrared radiation pretreating combined with film‐stacking hot pressing on the properties of SRPP composites. This approach significantly improved the properties of SRPP without nucleating agents. Compared with the original process, the tensile strength increased from 95 MPa to 128 MPa (a 35% improvement), while the flexural strength and flexural modulus increased from 23 MPa to 35 MPa (54%) and from 1.05 GPa to 2.25 GPa (114%), respectively. However, in systems with β ‐nucleating agents, infrared treatment compromised the interfacial defect repair effect, thereby restricting the performance optimization of SRPP under high‐pressure conditions. Nevertheless, infrared radiation preheating constitutes an effective processing strategy for self‐reinforced composites, providing a practical approach for producing high‐performance composites in industrial applications.