Controlled release mechanisms of sodium benzoate from a biodegradable polymer and halloysite nanotube composite

Multiscale polymeric composites combining a biodegradable matrix with low cost and biocompatible hybrid nanocarriers promise to supply a new generation of multipurpose devices for drug delivery. The aim of this work was to investigate the release mechanisms of sodium benzoate ( NaBz ) from halloysite nanotubes ( HNTs ) embedded in a biodegradable polymer matrix (poly(ϵ‐caprolactone)). To that purpose, different amounts of NaBz molecules were successfully incorporated into HNTs using a simple environmentally friendly procedure. The resulting HNT‐NaBz nano‐hybrids were then incorporated into a poly(ϵ‐caprolactone) matrix by high energy ball milling at ambient temperature and in dry conditions. Analysis of the resulting composites showed important effects of the HNT‐NaBz nano‐hybrids on the thermal and mechanical properties. Controlled drug release, followed by UV spectrophotometry, was also found to be dependent on the HNT‐NaBz relative fractions. Experimental data were thus analyzed using a modified Gallagher − Corrigan model and correlated with the nano‐hybrid morphologies.