Non-linear Analysis of Deformation Behaviour of HA/PLCL Porous Bio-composites

Abstract

It is well-known that the biology of bone mainly consists of the inorganic minerals, therefore bioceramics with similar constituent to that inorganic minerals of bone, e.g., hydroxyapatite [Ca10(PO4)6(OH)2] (HA) are extensively used for the scaffold fabrication. Recently, biodegradable synthetic polymers (biopolymer) are commonly used as composite materials to enhance the mechanical properties of pure HA porous scaffold. In this present work, HA based scaffold incorporated biopolymer namely, Poly(L-Lactide-co-ε-Caprolactone) (PLCL) is developed in an attempt to overcome the brittleness of pure HA scaffold. Further, two theoretical models are developed to express the non-linearity of the load-displacement curve obtained from the three-point bending test. Finally, the surface morphology of this material is observed using the Scanning Electron Microscopy (SEM). HA/PLCL material is observed to have a non-linear deformation where Model II depicts better accuracy compared to Model I with 9.6% RMS error while 11.61% RMS error for Model I. Due to the overestimation values given by Model I, Model II seems to have a better prediction on the load-displacement curve. The morphological structure of HA/PLCL shows two layers of interconnecting pores where the addition of polymer has enhanced the mechanical properties by providing ductility.

Keywords

• Biomaterials
• Porous
• PLCL
• Deformation
• Nonlinear

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