| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1468183 | Composites Part A: Applied Science and Manufacturing | 2006 | 5 Pages |
Hydroxyapatite particles of four different shapes, that is, micro, nano, spherical and plate, were used to fabricate hydroxyapatite filled poly(l-lactic acid) (HA/PLLA) composites. Effects of HA particle shape on the fracture behavior of HA/PLLA were investigated by mode I fracture testing, fracture surface measurement and scanning electron microscopy. It was found that the micro-HA/PLLA has the highest critical energy release rate, GIC, with the largest surface roughness, while GIC of the nano-HA/PLLA was lowest corresponding to the smallest surface roughness. The micro-HA/PLLA composites exhibited interfacial debonding and local ductile deformation of the PLLA matrix, indicating higher fracture energy and therefore, the highest GIC. On the other hand, the nano-HA/PLLA composites showed brittle fracture surface due to nano-scale interaction between PLLA fibrils and primary HA particles, corresponding to lower fracture energy and hence the lowest GIC.
