Evaluation of the flexural properties and bioactivity of bioresorbable PLLA/PBSL/CNT and PLLA/PBSL/TiO2 nanocomposites

Bioresorbable nanocomposites made from PLLA/PBSL blended with varying contents of carbon nanotubes (CNTs) and titanium dioxide (TiO2) nanotubes were prepared through melt compounding followed by compression molding. The resulting flexural properties were investigated by flexural test and the bioactive behavior was assessed by FESEM and EDX. A higher flexural modulus value was obtained with the addition of nanofillers. The formation of a bone-like apatite layer was observed on the surface of the nanocomposite containing TiO2 nanotubes after soaking in simulated body fluid (SBF) for 7 days. An increase in the water uptake of the PLLA/PBSL/TiO2 nanocomposite occurred with increased filler loading. The nanocomposite containing CNT exhibited an increasing trend of water absorption similar to the PLLA/PBSL blend. With prolonged immersion in SBF, the pH value of the SBF reduced slightly and weight loss of the samples increased.