Microstructural insights near compatibilized semicrystalline interfaces

Compatibilizers can increase polyolefin blend toughness by forming molecular bridges that stitch polymer interfaces together, potentially reducing the cost of mixed plastic recycling. While toughening mechanisms have been proposed, their validation is difficult given that experiments to resolve how compatibilizers interact with crystal or amorphous regions are challenging. To address this issue, we use a coarse-grained molecular dynamics model that forms crystal lamellae to investigate the interfacial structure of semicrystalline polymer blends with varying amounts of diblock compatibilizers. We compare simulation insights with experiments of polyethylene (PE) - polycaprolactone (PCL) blends that have been compatibilized with diblock deuterated PE – PCL, which provide an avenue to detect the fraction of compatibilizer-homopolymer crystallization. These findings offer microscopic insights into the structure near semicrystalline compatibilized polymer interfaces, which could aid in compatibilizer architecture optimization.