Syntheses and specific interactions of poly(epsilon-caprolactone)-block-poly(vinyl phenol) copolymers obtained via a combination of ring-opening and atom-transfer radical polymerizations

Abstract

A series of PCL-b-PVPh diblock copolymers were prepared through combinations of ring-opening and atom-transfer radical polymerizations of c-caprolactone and 4-acetoxystyrene, and subsequent selective hydrolysis of the acetyl protective group. This PCL-b-PVPh diblock copolymer shows a single glass transition temperature over the entire composition range, indicating that this copolymer is able to form a miscible amorphous phase due to the formation of intermolecular hydrogen bonding between the hydroxyl of PVPh and the carbonyl of PCL. In addition, DSC analyses also indicated that the PCL-b-PVPh diblock copolymers have higher glass transition temperatures than their corresponding PCL/PVPh blends. FT-IR was used to study the hydrogen-bonding interaction between the PVPh hydroxyl group and the PCL carbonyl group at various compositions.