Synthesis of block copolymers containing polybutadiene segments by combination of coordinative chain transfer polymerization, ring-opening polymerization, and atom transfer radical polymerization

Two triblock copolymers, polybutadiene-block-poly(ε-caprolactone)-block-poly(methyl methacrylate) (PBD-b-PCL-b-PMMA) and polybutadiene-block-poly(ε-caprolactone)-block-polystyrene (PBD-b-PCL-b-PS), are synthesized by combination of coordinative chain transfer polymerization (CCTP), ring-opening polymerization (ROP), and atom transfer radical polymerization (ATRP). The molecular structures of these polymers are determined by ¹H NMR and gel-permeation chromatography (GPC) analysis. The resulting triblock copolymers are evaluated as compatibilizing agents for highly immiscible binary PBD/PMMA and PBD/PS blends. The presence of these compatibilizers substantially reduces the average PMMA or PS droplet size. Furthermore, static water contact angle experiments are employed to assess the modification of the surface properties of nonpolar PBD.