Decoupling polymer molecular chains and carbon fibres orientation by their dielectric anisotropy

Carbon fibre reinforced polymers (CFRPs) are widely used in various industry fields, owing to their superior mechanical properties. The orientation of polymer molecular chains and carbon fibres plays a crucial role in determining the mechanical properties of CFRPs. The complex interactions between them often lead to ambiguous dominant rules of mechanical properties. However, existing methods cannot decouple the orientation of polymer molecular chains and carbon fibres, resulting in the above-mentioned problems remaining a challenge. In this study, the orientation dynamics of polymer molecular chains and carbon fibres was decoupled by the dielectric anisotropy method for the first time. The accuracy of the decoupled orientation of polymer molecular chains and carbon fibres was verified by the polarized Raman spectroscopy and X-ray computed tomography methods. Noteworthily, linear low-density polyethene (LLDPE) orientation dominates the elastic modulus of LLDPE/carbon fibre was proved. Our method opens a new window for the design of high-performance CFRPs.