BIOMATERIAL
mechanical and surface properties
Nur Istianah, ST.,MT.,M.Eng
Mechanical and surface properties
• Tensile strength
• Ductility
• Hardness
• Viscoelasticity
• Surface properties
Tensile test
compressive Tensile
load
Torsional Shear
strain
Tensile test
Tensile test
• Engineering stress
• Engineering strain
• E= modulus Young
Tensile strength
Modulus
• Resistance to force
• Higher modulus lower elasticity
• Influenced by
temperature
Polymer
• Molecular weight of polymerinfluence tensile strength
Ductility
Ductility
Hardness
Hardness
• Elastic deformation of polymer is reversibel. Polymer can recover to initial shape after the tensile strength
• Viscos deformation is irreversible
Viscoelasticity
Relaxation modulus
• Viscous hs lowest
tendency to stress
Viscoelasticity
Surface properties
Biomaterial surface
Surface properties acn be caracterized by TEM, AFM, etc
Surface properties
• Hydrophobic/philic
• Water sorption/solubility
• Protein sorption
• Biocompatibility
• Biodegradation
Protein sorption
• Biomaterial surfaces can be modified by amino acid to adsorp the protein
Hydrophobic/philic
• Superhydrophobic is a kind of modification in anti- biofouling since water could not be adsorb in
biomaterial
Surface modification
Surface modification
Surface modification technique
• Immobilization
• Organic thin film
• Self Assembly
• Layer-by-layer deposition
Immobilization: cell adhesion
Organic thin film: fouling and anti-fouling
Self Assembly: joint implant
• SA has closely packed
• Such as lubricant layer
• Less friction in hip and joint implant
