Synthesis and Characterization of PLA-Micro-structured Hydroxyapatite Composite Films

Abstract

This article presents a facile synthesis method used to obtain new composite films based on polylactic acid and micro-structured hydroxyapatite particles. The composite films were synthesized starting from a polymeric solution in chloroform (12 wt.%) in which various concentrations of hydroxyapatite (1, 2, and 4 wt.% related to polymer) were homogenously dispersed using ultrasonication followed by solvent evaporation. The synthesized composite films were morphologically (through SEM and atomic force microscopy (AFM)) and structurally (through FT-IR and Raman spectroscopy) characterized. The thermal behavior of the composite films was also determined. The SEM and AFM analyses showed the presence of micro-structured hydroxyapatite particles in the film’s structure, as well as changes in the surface morphology. There was a significant decrease in the crystallinity of the composite films compared to the pure polymer, this being explained by a decrease in the arrangement of the polymer chains and a concurrent increase in the degree of their clutter. The presence of hydroxyapatite crystals did not have a significant influence on the degradation temperature of the composite film.

Assessment of the Mechanical and Thermal Properties of Injection-Molded Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/Hydroxyapatite Nanoparticles Parts for Use in Bone Tissue Engineering

“…The onset of degradation was also reduced for the most filled sample, showing a T 5% value of 254.8 °C, which represents a reduction of approximately 18 °C in comparison to the unfilled P(3HB- co -3HHx) sample and its nanocomposites at low contents. These results further indicate that the nanoparticles formed aggregates at high contents, which created volumetric gradients of concentration [ 66 ]. In this regard, Bikiaris et al [ 65 ] suggested that when high amounts of nanosized filler aggregates are formed, the structure shifts from nanocomposite to microcomposite and, thus, the shielding effect of the nanosized particles is lessened.…”

“…The temperature at which the maximum mass loss rate occurred (T deg ) increased from 296.7 °C, for the neat P(3HB- co -3HHx) part, to 300.9 °C, for the part of P(3HB- co -3HHx) filled with 2.5 %wt of nHA. This increase in thermal stability has been previously ascribed to the formation of strong hydrogen interactions and Van der Walls forces between the inorganic nanoparticles and the biopolymer chains during the melt-mixing process [ 66 ]. The values of T deg remained nearly constant, showing no significant differences for nHA contents from 2.5 to 10 wt %, but it significantly decreased to 295.6 °C in the part filled with 20 wt % of nHA.…”

Biocompatibility and Physico-Chemical Properties of Highly Porous PLA/HA Scaffolds for Bone Reconstruction

“…The current work aims to fill this gap, and attempts to carry out in vivo studies in addition to in vitro investigations to predict real-life applications in the biomedical field. Moreover, very few articles have been reported exploring the cytocompatibility of poly (lactic acid)/hydroxyapatite composites for the reconstruction of maxillofacial defects [ 26 , 27 , 28 ]. The present work deals with the preparation of porous PLA/HA scaffolds, and examines controlling their pore size by using solvent casting and a particulate leaching method.…”

“Polylactic acid-polyethylene glycol-hydroxyapatite composite” an efficient composition for interference screws

“…The peaks appear again with increasing the HA level. This could be explained by the fact that the presence of HA leads to a decrease in the crystallinity of PLA as the presence of these particles limits the mobility of PLA chains and decreases the orientation of polymer chains by increasing their degree of disorder [29]. This chain immobilization in the interphasial region results in a T g peak in the DSC curve for HA-containing samples [26].…”