title: Apatite formation on CaO-free polydimethylsiloxane (PDMS)-TiO2 hybrids.
abstract: Polydimethylsiloxane (PDMS)-TiO(2) hybrids with PDMS (M=550)/tetraethylorthotitanate molar ratios at 0.27, 0.68 and 1.35, i.e. Si/Ti atomic ratios at 2, 5 and 10 (hybrids PD2, PD5 and PD10, respectively) were prepared by a sol-gel method. Hybrid PD2 formed many cracks. Hybrids PD5 and PD10 were subjected to hot-water treatment 80 degrees C for 7 d. Hybrid PD5 produced cracks, whereas hybrid PD10 was crack-free after the hot-water treatment. Hybrid PD10 took a homogeneous amorphous structure before the hot-water treatment, and precipitated anatase particles 10-20 nm in size after the hot-water treatment. Hybrid PD10 did not form apatite on its surface in a simulated body fluid before the hot-water treatment, but formed it after the hot-water treatment. The obtained hybrid showed elastic deformation as large as 200% after the hot-water treatment. This kind of hybrid could be useful as a new type of bone-repairing material.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan. kamitaka@ms.aist-nara.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kamitakahara
authors.forename: M
authors.initials: M
authors.lastname: Kawashita
authors.forename: N
authors.initials: N
authors.lastname: Miyata
authors.forename: T
authors.initials: T
authors.lastname: Kokubo
authors.forename: T
authors.initials: T
authors.lastname: Nakamura