Effects of different fluorination routes on aramid fiber surface structures and interlaminar shear strength of its composites

► The ILSS is improved by appropriate fluorination routes. ► The inappropriate fluorination route sharply decreases the ILSS. ► Different fluorination routes lead to different fiber surface morphology structures. ► Physisorbed water accelerates chain scission and leads to formation of unstable structures. ► These unstable structures became weak interface between the fiber and matrix.