title: Effect of particle morphology and polyethylene molecular weight on the fracture toughness of hydroxyapatite reinforced polyethylene composite.
abstract: Fracture toughness testing has been performed on hydroxyapatite-polyethylene composites. Sintered and unsintered grades of hydroxyapatite and two grades of high-density polyethylene were used to make 40 vol % hydroxyapatite composites. Compact tension testing was performed at both room temperature and at 37 degrees C and at three strain rates. The effect of increasing the loading rate from 2 to 200 microm s(-1) was to increase the fracture toughness. Increasing the testing temperature or decreasing the surface area of the reinforcing particles also increased the fracture toughness. However, using a lower molecular weight, injection moulding, grade of polyethylene reduced the fracture toughness. Thus for higher fracture toughness, a low surface area sintered hydroxyapatite in a high-molecular weight polyethylene is required.
authors.affiliation: Department of Materials and IRC in Biomedical Materials, Queen Mary, University of London, Mile End Road, London E1 4NS, UK. J.O.Eniwumide@quml.ac.uk
authors.forename: J O
authors.initials: JO
authors.lastname: Eniwumide
authors.forename: R
authors.initials: R
authors.lastname: Joseph
authors.forename: K E
authors.initials: KE
authors.lastname: Tanner
mesh_terms: D001672:Biocompatible Materials; D003188:Composite Resins; D017886:Durapatite / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D008970:Molecular Weight; D020959:Polyethylene / Q000737:chemistry*; D011095:Polyethylenes / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D003188:Composite Resins; D011095:Polyethylenes; D020959:Polyethylene; D017886:Durapatite