(59c) Colloidal Surface Stabilization Ability of Zwitterionic Copolymers

Zwitterionic polymers are gaining importance as coatings in biomaterials applications as they have been observed to have improved antifouling properties compared to the more commonly used poly(ethylene oxide). The synthetic accessibility of zwitterionic-based polymers, combined with highly efficient conjugation strategies, allows access to polymers with unique chemical functionalities and elaborate polymer architectures and enables the study of the effect of polymer architecture on system properties. In this work we will examine the performance of zwitterionic copolymers that adsorb onto surfaces in a brush-like conformation and stabilize nano- or micrometer-sized colloids. Compared to poly(ethylene oxide), copolymers based on poly(propylene oxide) and 2-methacryloyloxyethyl phosphorylcholine (MPC) stabilize colloids with only a fraction of repeat units of those necessary for stabilization by PEO analogs. We show that solvated thickness, and not monomer chemistry, is the dominant characteristic in the ability of a polymer brush to stabilize a colloid surface. The adsorptive stabilization ability of PMPC copolymers toward colloidal surfaces will enable the design and development of novel biomaterials.