Surface characterization of antibiofouling silicone elastomer by hydrophilication

Biomimetic synthetic phospholipid polymer containing phosphorylcholine group; 2-methacryroyloxyethyl phosphorylcholine (MPC), has improved the surface property of biomaterials. Both hydrophilic and anti-biofouling surface were prepared on polydimethylsiloxane (PDMS) with 2-methacryroyloxyethyl phosphorylcholine (MPC) grafted by surface-initiated photo-induced radical polymerization. Benzophenone was used as photoinitiator and UV irradiation time was changed within 120 min. The poly(MPC) grafted PDMS surfaces were characterized by XPS, AFM, SEM, ellipsometry and static water contact angle (SCA) measurements. The contact angles were lineally decreased with an increase in UV irradiation time while the P/C ratio and graft layer thickness were increased with UV irradiation time. The roughness of poly(MPC) grafted PDMS surface was within 5 nm in height. The formation of large domains for poly(MPC)-g-PDMS surface was caused by an aggregation of zwitterionic phosphorylcholine groups due to their strong intermolecular interactions.