Materials Science Forum Vol. 569

Abstract: TiO2 / KGM composite membranes were prepared by blend. Effects of the content of TiO2 and glycerol, ratio of PVA to KGM on tensile strength of membranes were investigated. Structure and Morphology of TiO2 / KGM films were characterized by SEM, XRD and IR. Furthermore, anti-bacteria properties of composite films were evaluated. The results showed that there were hydrogen bonding interactions between konjac glucomannan molecule, PVA and titania particle after irradiation. Composite membranes enable the antibacterial properties improved by adding an appropriate amount of TiO2, but mechanical properties decreased. The composite membrane tensile strength decreased with increasing glycerol content but increased with PVA glucomannuronate composite ratio increasing.

Abstract: Nano-hydroxyapatite (n-HA)/chitosan (CS)/konjac glucomannan (KGM) composite was prepared by integrating composition and molding. Then, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analyze the physical, chemical and degradable properties of the composite before and after in simulated body fluid (SBF). Moreover, study in vitro test for drug delivery revealed that the amount of released pentoxifylline (1-[5-oxohexyl]-3,7-dimethylxanthine)(PTX) reached a plateau and equaled 80% of the drug loaded in an implant. The newly develop n-HA/CS/KGM composite may serve as a good degradable biomaterial for implantable drug delivery system (IDDS) in bone tissue engineering.

Abstract: In this work, Al2O3-Al composite coatings with different compositions (Al2O3-5wt.% Al, Al2O3-10wt.% Al and Al2O3-15wt.% Al) were deposited by plasma spraying. The effect of Al addition on the mechanical properties of coatings was explored in terms of microhardness, fracture toughness and sliding wear rate. An additional statistical study of Weibull analysis was carried out for further investigating the mechanical data variation. The increase in Al addition was realized to show little effects to decrease porosity of coatings. With the increase in Al addition, the microhardness of coatings decreased from 869 to 742 Hν0.2 along with larger fluctuation in microhardness values indicated by lower Weibull modulus (5.7-10), whereas toughness of coatings was improved ranging from 2.7 to 4.1 MPa.m1/2. Friction tests showed that the Al additions effectively contribute to decrease the friction coefficient of coatings sliding against steel counterpart. Among various coatings, the Al2O3-15wt.% Al coating exhibits lowest friction coefficient but worst wear resistance. This may arise due to its significantly decreased microhardness.