Humidity sorption of lactose/sodium montmorillonite nanocomposites
(English)Manuscript (preprint) (Other academic)
Understanding of water sorption is of high importance in materials science as water may change materials properties promoting degradation, relaxations, or recrystallization. In this study, we investigated the humidity sorption in co-spray-dried lactose/sodium montmorillonite nanocomposites with varying lactose loading with the aim to increase the knowledge of the water sorption in this type of materials. It was demonstrated that the intercalation of lactose in the Na‑MMT clay decreased hygroscopicity of the composite despite high water affinity of both materials. As the cations in interlayer space of montmorillonite play an essential role in water sorption in the clay, we gained the molecular level understanding of Na+ interactions with lactose molecules and clay surface in the nanocomposites with molecular dynamic simulations and 23Na solid-state NMR. In conclusion, we demonstrated that the decreased hygroscopicity of the materials can be explained by interactions of lactose with the Na+ and the clay surfaces in the MMT interlayer space of lactose/Na-MMT nanocomposites.
IdentifiersURN: urn:nbn:se:uu:diva-300154OAI: oai:DiVA.org:uu-300154DiVA: diva2:950906