Compatibilization of immiscible polymer blends through ionic interactions

Polymer blending provides an attractive and sustainable platform to obtain materials with desirable physicochemical properties, but often results in immiscible blends exhibiting poor mechanical and optical properties that limits applicability. To address this challenge, we demonstrate that ionic interactions are a powerful tool for polymer compatibilization, recycling, and upcycling. In this work, ionic bonds efficiently compatibilized a highly immiscible blend of poly(n-butyl acrylate) P(nBA) and poly(dimethylsiloxane) (PDMS). At 10 mol% or less incorporation, pendant acidic moieties were introduced in P(nBA) through reversible addition–fragmentation chain-transfer copolymerization, and pendant basic moieties were tethered along the PDMS backbone through a facile thiol-ene reaction. Stoichiometric acid-base polymer blends exhibited optical clarity and single glass transition temperatures. In addition, oscillatory shear rheology is utilized to probe the blend dynamics as a function of temperature. The combined synthetic and characterization strategy is opening significant opportunities for understanding and exploiting low levels of ionic functionalization in commercially important polymeric systems.