Electrospinning of biodegradable polylactide/hydroxyapatite nanofibers: Study on the morphology, crystallinity structure and thermal stability

Aligned mats of poly(lactic acid) (PLA) nanofibers containing nanosized hydroxyapatite filler have been obtained via electrospinning onto a rotating mandrel. Their structure and morphology have been characterized as a function of the production parameters, by SEM, DSC, DMA and WAXS, with emphasis in the effects of the take-up velocity. SEM, DSC and X-ray diffraction studies confirmed a reduction in fiber diameter, an increase of fiber orientation and a highly crystalline structure of the mats collected at higher speed due to the stretching produced during the process. Double melting behavior was observed, suggesting the presence of two crystalline forms. Moreover the higher storage modulus (E′ modulus), and glass transition temperatures of the higher speed collected mats were correlated with an enhancement in the thermal stability and nanofiller distribution.