Coupling Effect of Mechanical and Thermal Rejuvenation for Polystyrene: Toward High Performance of Stiffness, Ductility, and Transparency

The challenge of hitherto elaborating a workable approach to overcome the conflicts between stiffness, ductility, and transparency of polystyrene (PS) still remains among academia and industry. In this work, we found an unprecedented strategy to address this obstacle by combining mechanical and thermal rejuvenation. A PS film with remarkable stiffness, ductility, and transparency (83.1 MPa, 87.9, and 83.1%) is achieved through this facile strategy. Through investigating the relationship between macroscopical mechanical performance and mobility of molecular chains, the mechanism of the coupling effect is elucidated. On heating up the mechanically rejuvenated films, the intersegmental interaction is weakened and external pressure breaks the force balance. Thus, the oriented chain network might be more inclined to form a densely arranged structure, and it provides more strengthened elements during yielding. This work provides a preferable and industrially scalable method to prepare high-performance PS materials and might be a significant guidance for other amorphous polymers.

Automated summary

This study successfully prepared PS films with remarkable stiffness, ductility, and transparency by combining mechanical and thermal rejuvenation. The mechanism of the coupling effect was elucidated through investigating the relationship between macroscopical mechanical performance and mobility of molecular chains.