Induced magnetic properties to surface-modified mesoporous porous clay heterostructures for sensor application in food packaging

Abstract

Porous clay heterostructures (PCHs) are a recent class of solid porous materials, where their surface areas are higher than those of organoclay. In this work, a PCH surface was modified by Fe ions (Fe²⁺ and Fe³⁺) from ferric chloride hexahydrate. Subsequently, these as-synthesized mesoporous materials were blended with polylactide to yield polylactide-clay nanocomposites for food packaging application. The PCHs had surface areas of 412-688 m²⁺/g, depending on the various molar ratios of dodecylamine/TEOS. SEM images and EDX micrographs of the Fe ion in PCH showed successful incorporation of the Fe ions in the PCH. Magnetic PCHs exhibited a remarkably significant bacteriostatic effect against Escherichia coli and Staphylococcus aureus. The Tg and Tm of PLA/5%wt PCL were lower than neat PLA. The thermal properties of PLA/5%wt PCL/1-4%wt magnetic PCH nanocomposites increased with higher content of magnetic PCH. The PLA nanocomposite showed a lower oxygen gas permeability rate than neat PLA due to enhancing barrier properties of the magnetic PCH.