title: Nano-hydroxyapatite/poly(L-lactic acid) composite synthesized by a modified in situ precipitation: preparation and properties.
abstract: Nano-hydroxyapatite/poly(L-lactic acid) (nano-HA/PLLA) composites with uniform HA distribution and good mechanical performance were fabricated by a modified in situ precipitation method, using Ca(OH)(2) and H(3)PO(4) as precursors for the synthesis of HA phase. This method has solved the aggregation problem of the nano-sized particles in the polymer matrix. The X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy were used to characterize the phase composition, chemical interactions and morphology of the composites, while the mechanical properties were determined by compressive measurements. The results show that the rod-like nano-HA particles synthesized by this method were uniformly distributed in the PLLA matrix. The compressive strength and Young's modulus of the composites were greatly enhanced and reached the values of 155 MPa and 3.6 GPa at 20 wt% HA content, respectively, which are much higher than those of the reference samples fabricated by direct mixing of PLLA with nano-HA particles. This supports the potential of these composites for applications in bone tissue engineering and load bearing bone defects repair.
authors.affiliation: Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, People's Republic of China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Lu
authors.forename: Z
authors.initials: Z
authors.lastname: Zhuang
authors.forename: X P
authors.initials: XP
authors.lastname: Wang
authors.forename: Q F
authors.initials: QF
authors.lastname: Fang
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D018786:Bone Substitutes / Q000138:chemical synthesis / Q000737:chemistry; D011232:Chemical Precipitation; D003188:Composite Resins / Q000138:chemical synthesis* / Q000737:chemistry; D019245:Compressive Strength / Q000502:physiology; D017886:Durapatite / Q000138:chemical synthesis* / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods; D014961:X-Ray Diffraction
chemical_list: D018786:Bone Substitutes; D003188:Composite Resins; D011091:Polyesters; C499699:hydroxyapatite-polylactide; D017886:Durapatite