title: Self-initiated surface grafting with poly(2-methacryloyloxyethyl phosphorylcholine) on poly(ether-ether-ketone).
abstract: Poly(ether-ether-ketone) (PEEK)s are a group of polymeric biomaterials with excellent mechanical properties and chemical stability. In the present study, we demonstrate the fabrication of an antibiofouling and highly hydrophilic high-density nanometer-scaled layer on the surface of PEEK by photo-induced graft polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) without using any photo-initiators, i.e., "self-initiated surface graft polymerization." Our results indicated that the diphenylketone moiety in the polymer backbone acted as a photo-initiator similar to benzophenone. The density and thickness of the poly(MPC) (PMPC)-grafted layer were controlled by the photo-irradiation time and monomer concentration during polymerization, respectively. Since MPC is a highly hydrophilic compound, the water wettability (contact angle <10 degrees) and lubricity (coefficient of dynamic friction <0.01) of the PMPC-grafted PEEK surface were considerably lower than those of the untreated PEEK surface (90 degrees and 0.20, respectively) due to the formation of a PMPC nanometer-scale layer. In addition, the amount (0.05 microg/cm(2)) of BSA adsorbed on the PMPC-grafted PEEK surface was considerably lower, that is more than 90% reduction, compared to that (0.55 microg/cm(2)) for untreated PEEK. This photo-induced polymerization process occurs only on the surface of the PEEK substrate; therefore, the desirable mechanical properties of PEEK would be maintained irrespective of the treatment used.
authors.affiliation: Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kyomoto
authors.forename: Toru
authors.initials: T
authors.lastname: Moro
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Takatori
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawaguchi
authors.forename: Kozo
authors.initials: K
authors.lastname: Nakamura
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000042:Absorption; D001577:Benzophenones; D001672:Biocompatible Materials / Q000737:chemistry*; D003460:Crystallization / Q000379:methods; D007659:Ketones / Q000737:chemistry*; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D010316:Particle Size; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers; D016062:Porosity; D013499:Surface Properties
chemical_list: D001577:Benzophenones; D001672:Biocompatible Materials; D007659:Ketones; D008689:Methacrylates; D011108:Polymers; D010767:Phosphorylcholine; C063834:polyetheretherketone; D011092:Polyethylene Glycols; C070638:2-methacryloyloxyethyl phosphorylcholine