Deformation and failure of glassy polymer-polymer interfaces compatibilized by linear multiblock copolymers

When two different polymers are blended, they form phase-separated emulsions with weak interfaces. These recycled materials are inferior to the original plastics, posing a fundamental challenge for recycling mixed plastic waste streams. An emerging solution to this problem is the addition of a multiblock copolymer compatibilizer to ``stitch together'' the interface. Using coarse-grained molecular dynamics simulations, Collanton and Dorfman examined how interfacial toughness is impacted by the number of blocks in the compatibilizer and the copolymer loading, connecting the microstructural features of the interface to its failure mechanism.