Effect of iron oxide nanoparticles on the thermal characteristics of supramolecular, dendritic and macromolecular capping agents

Abstract

The present study aimed at the enhancement of the thermal characteristics of different capping agents belonging to different macromolecular families, with the incorporation of iron oxide nanoparticles. Iron oxide nanocomposites were prepared following a simple reduction protocol using sodium borohydride (NaBH4) succeeded by air oxidation. Three iron oxide composites were prepared using different biocompatible capping agents. The capping agents used in the present study were supramolecular β-cyclodextrin, dendritic hyperbranched polyglycerol and macromolecular starch. The chemical nature of the composites was successfully confirmed by spectroscopy. The well-characterized composite systems were studied for their thermal characteristics using TG/DTG and DSC measurements. The primary focus of the study was to analyse any change in the thermal behaviour of the pure encapsulating systems on incorporation with the iron oxide species. The analysis was conducted by comparing the TG/DTG and DSC measurements of the pure capping agents- cyclodextrin, hyperbranched polyglycerol and starch with their respective nanoparticle incorporated composites. All the three capping agents were found to decompose in the temperature range 250–450 °C But these systems on incorporation of iron oxide nanoparticles have gained more thermal stability. Their decomposition shifted to a higher temperature with broadened curves suggestive of a slow and steady degradation pattern. DSC studies showed that the incorporation of IONPs could effectively prevent melting of the capping agents by which they could be propagated to a wide range of applications.