Tailor-Made Fibrous Nanohydroxyapatite/Polydimethylsiloxane Composites: Excavating the Role of Nanofiller Aspect Ratio, Amorphicity, and Noncovalent Surface Interaction

Abstract

This work holds significance in designing biomimetic implants where biocompatibility and strength are two critical concerns. In the work mentioned herein, hydroxyapatite nanofibers of varying aspect ratios have been synthesized by the soft template assisted method. These nanoparticulates have been successfully introduced into the polydimethylsiloxane (PDMS) matrix through a solution casting technique, and this is probably the first successful attempt made. Nanocomposites prepared with longer nanofibers (300–500 nm length) showed more improvement in various physicomechanical and thermal properties compared with those prepared with lower aspect ratio nanofibers (10.3 versus 4.5). In-depth analysis revealed that a combined effect of several factors leads to these differences. Besides the most important factor, viz., aspect ratio of the nanofibers, the amorphicity of nanofibers and adherence of polymer on the nanofiller surface, i.e., noncovalent surface modification of nanofiller and restriction of microcrys...