Investigation of a Polyamide 6 ( PA6 ) and Polybutylene Succinate ( PBS ) Blend as Candidate Matrix for Self‐Healing Application

ABSTRACT In this work, polyamide 6/polybutylene succinate (PA6/PBS) blends, containing 20% to 50%vol of PBS, were melt compounded and hot pressed. Their rheological, morphological, thermo‐mechanical, and fracture toughness properties were analyzed. Rheological analysis demonstrated that lower PBS contents increased the storage and loss moduli of PA6, maintaining good processability. FT‐IR and FESEM observations showed the formation of PBS domains dispersed within the PA6 matrix. Mechanical tests revealed a progressive decrease in tensile modulus and strength with PBS content. However, blends containing 20%–30%vol PBS retained suitable levels of stiffness and strength compared to neat PA6. Particularly, the formulation containing 30%vol of PBS was selected as a candidate composition for self‐healing assessment. The repair efficiency was quantified as the recovery of the fracture toughness after thermal treatment at 140°C. A recovery of 40% of the original dynamic fracture toughness under impact conditions was obtained, attributed to a smooth fracture surface generated at high strain rate, which could have promoted possible flow of the molten PBS across the crack interface during the healing process. Thus, the selected blend developed within this investigation could be considered in the future for the preparation of multifunctional composite laminates with thermal healing capability.