Enhancing the mechanical properties of electrospun chitosan/poly(vinyl alcohol) fibers by mineralization with calcium carbonate

Mineralization of electrospun chitosan/poly(vinyl alcohol) (PVA) with CaCO₃ was performed as a reinforcement strategy to produce a biocompatible material with good mechanical properties. Disk-like layered and cubic CaCO₃ particles were formed when the composites were dried at low and high concentrations of CO₂, respectively, followed by a transformation of the amorphous CaCO₃ into calcite. The highest ultimate stress value was found to be 44 ± 3.2 MPa for the composite with 17 wt% of CaCO₃, which was crosslinked by glutaraldehyde and dried at high concentrations of CO₂. The highest value of the Young’s modulus was 2328.35 ± 204.9 MPa for the composite with 34 wt% of CaCO₃ that was dried at high concentrations of CO₂. The bioactivity of the obtained composites was tested by 6-day incubation in simulated body fluid (SBF), resulting in flake-like apatite structures grown on the composite surface. The composites retained around 50 % of their ultimate stress value after immersion in SBF. The mineralization of electrospun chitosan/PVA with CaCO₃ produced composites with enhanced mechanical properties, which can be potentially used as scaffolds in tissue engineering applications.