Introductory Remarks

Block copolymers have been investigated as compatibilizers in immiscible homopolymer blends for over 40 years. Blends without compatibilizers are known to exhibit poor mechanical properties, with low values of strain-at-break and yield stress, making them unsuitable for recycling into new products. To effectively compatibilize these systems, thus, it is critical that block copolymers improve these mechanical properties.

Experimental successes have confirmed that block copolymers accomplish this by facilitating stress-transfer across homopolymer-homopolymer interfaces. However, they are limited in their ability to probe molecular-level details such as chain conformation at the interface. Additionally, they face practical limitations in their ability to explore the large compatibilizer design space. Leveraging GPU-accelerated molecular dynamics, we set out to elucidate the role and mechanism of compatibilizers in imparting mechanical strength to blends, with the ultimate goal of clarifying rules for optimizing compatibilizer design.