In situ preparation and characterization of a novel gelatin/poly(D,L-lactide)/hydroxyapatite nanocomposite

A novel biodegradable polymer-ceramic nanocomposite was prepared using the in situ preparation method, which consisted of gelatin (gel), poly(D,L-lactide) (PDLLA), and hydroxyapatite (HA) nanofibers. In this article, the HA nanofibers with length/diameter (L/D) ratio of 19.8 in gel/PDLLA/HA nanocomposites were synthesized and precipitated in polymeric matrix by one-step hydrothermal mineralization. The crystalline phases, structural morphology, mechanical characterization, and chemical interaction of gel/PDLLA/HA nanocomposites were investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, mechanical test, and Fourier transform infrared spectroscopy. The results showed that the crystalline HA nanofibers were uniformly mineralized in gel and PDLLA matrix and the interaction between Ca(2+) in HA (nanofibers and negative-charged functional groups in gel and PDLLA molecular chains was formed. Thus, the schematic model of two polymeric chains bridged by inorganic nanofibers was designed on the basis of the experimental results. Moreover, it can clearly explain why the mechanical properties of gel/PDLLA/HA nanocomposites turned strong.