Characterization and application of poly(β-hydroxyalkanoates) family as composite biomaterials

Some polyhydroxyalkanoates (PHA), polyhydroxybutyrate (PHB) and copolymers poly(hydroxybutyrate-co-hydroxyvalerate) (P(HB-co-HV)), were characterized by different techniques (GPC, DSC, DMA, FTIR, DRX) in order to be used in hydroxyapatite (HA) composites. These polymers presented high molecular weights and are semicrystalline materials. The crystallinity has a slight tendency to decrease with the increasing HV content in the copolymer. PHA/HA composites prepared at the same composition, showed a lower elastic modulus than 0 and 8% HV content. The composite P(HB-co-8%HV)/HA (30% w/w) has the highest modulus. In addition, this composite has a mechanical strength in compression of 62 MPa, which is about the same order of magnitude of several human bones and thus it is interesting as biomaterial for use in fracture fixation.